• UV PVC Marble Sheet,Elegant PVC Wall Panel for Home Decor
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    UV PVC Marble Sheet,Elegant PVC Wall Panel for Home Decor pvc marble panel for interior decoration MaterialPVC +calcium powder+ additiveDensity聽2.0g/cm^3 聽Size1220*2440 mm and customizedThickness1.3-6.0 mm TechnologyHot stamping foil & UV-coatingCertificateCE & SGS Installation1.Glued on the wall 2.Aluminum trim profile 3. Sealant installationGlue 聽Neutral Silicone Sealant Adhesive ColorMarble, wood, solid color & 3D. More than 100 designs in total. Composition35% pvc, 62% CaCo3, 3% additive. 聽Structure聽PVC board + Hot stamp foil + UV-coating + PE protection film. Common Thickness For Reference Thickness(mm)Tolerance (mm)Weight(kg/pc)Tolerance(kg)MOQ(20GP/pcs) 1.3mm+-0.058.0kg/pc+-0.53000pcs 1.5mm+-0.058.2kg/pc+-0.52700pcs 2.0mm+-0.0512.3kg/pc+-0.52000pcs 2.5mm+-0.0515.3kg/pc+-0.51600pcs 2.8mm+-0.0517.2kg/pc+-0.51400pcs 3.0mm+-0.0518.4kg/pc+-0.51300pcs 3.2mm+-0.0519.6kg/pc+-0.51250pcs 3.5mm+-0.0521.5kg/pc+-0.51150pcs 4.0mm+-0.0524.5kg/pc+-0.51000pcs 5.0mm+-0.0530.7kg/pc+-0.5800pcs 6.0mm+-0.0536.8kg/pc+-0.5650pcsCustomized UV Wall Panel website:http://www.cswooddecor.com/uv-wall-panel/
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  • wholesale Swimming Pool Chemical Production Method Product Name:Sodium Dichloroisocyanurate CAS. No.2893-78-9 Molecular formula:C3Cl2N3NaO3 Product Introduction Product Name: Sodium Dichloroisocyanurate CAS. No.2893-78-9 Molecular formula: C3Cl2N3NaO3 Application Sodium Dichloroisocyanurate is a compound used as a disinfectant, algicide, industrial deodorant and detergent. It exists in some newer water purification tablets or filters. It is more effective than previous use of halazone water disinfectants. The mechanism of action is to release chlorine gas at a constant rate of low concentration, which can be used for industrial water treatment, swimming pool water treatment, drinking water disinfection, wool shrinkproof treatment and textile industry bleaching. It can also be used for the environmental disinfection of families, hotels, hospitals, aquaculture, poultry, pets and public places. Product Parameter (Specification) Product NameSodium Dichloroisocyanurate CAS No.2893-78-9 Molecular FormulaC3Cl2N3NaO3 Nickname (s)Dichloroisocyanuric; acid, sodium salt; 3,5-Dichloro-2-hydroxy-4,6-s-triazinedione sodium salt; Dichloroisocyanuric Acid Sodium Salt; dikonit; simpla; Sodium Dichloroisocyanurate; DCCNA; SDIC; Dichloro-s-triazinetrione sodium salt Molecular weight219.94600 Precise quality218.92100 PSA79.95000 LOGP-0.44740 Prodection Details Appearance and property: white crystalline granule or powders or flakes Density: 2.06 g/cm3 Boiling point: 306.7 C at 760 mmHg Melting point: 225 ° C Flashing Point: DHS 139.3 C Water solubility: 30G/100ML (25 C) Stability: Stable. The Oxidizing agent - contact with combustible material may lead to the fire. The Incompatible with strong outside, strong Oxidizing agents nitrogen with many nitrogen-containing compounds to form explosive nitrogen triiodide. Moisture-sensitive. Storage conditions: 0-6 C Vapor pressure: 7.05 e-05 mmHg at 25 ° C Our Advantages 1. International first-class production capacity (rich inventory, stable supply ability; we have warehouses all over China domestic cities). 2. Top production test equipment 3. Advanced research and development center 4. Strict quality 5. Professional logistics team to ensure the safety of transportation and timely arrival of goods 6. Professional service team (For details, kindly check the Letter of commitment before and after sales in "About Us" from Homepage). Our Factory And Company Our factory advanced production technology and equipment. FactoryCompany Major Exporting Countries Deliver, Shipping And Serving We will provide you with quality products and professional services. You are always welcome to consult us. We will provide you with a comprehensive offer, including quotation, payment, mail, etc. We look forward to your inquiry. Cooperation Cases Production Methods 1. By ammonium chloride and urea together after heating reaction acidification, alkali solution, through chlorination, and then dry. 2. Isocyanuric acid, sodium hydroxide, chlorine gas as raw materials. 3. Sodium hydroxide and cyanuric acid were successively added to the chlorination kettle, and the molar ratio of feed was 2:1. H equals zero at p4. 5~8. 5, temperature 5~1 0 ℃ under continuous chloride, chlorine gas is piped in under two different cyanuric acid chloride, with sodium hydroxide and sodium salt. 4. Reaction of cyanuric acid and chlorine gas.wholesale Swimming Pool Chemical website:http://www.eastchemy.com/basic-organic-chemistry/swimming-pool-chemical/
    wholesale Swimming Pool Chemical Production Method Product Name:Sodium Dichloroisocyanurate CAS. No.2893-78-9 Molecular formula:C3Cl2N3NaO3 Product Introduction Product Name: Sodium Dichloroisocyanurate CAS. No.2893-78-9 Molecular formula: C3Cl2N3NaO3 Application Sodium Dichloroisocyanurate is a compound used as a disinfectant, algicide, industrial deodorant and detergent. It exists in some newer water purification tablets or filters. It is more effective than previous use of halazone water disinfectants. The mechanism of action is to release chlorine gas at a constant rate of low concentration, which can be used for industrial water treatment, swimming pool water treatment, drinking water disinfection, wool shrinkproof treatment and textile industry bleaching. It can also be used for the environmental disinfection of families, hotels, hospitals, aquaculture, poultry, pets and public places. Product Parameter (Specification) Product NameSodium Dichloroisocyanurate CAS No.2893-78-9 Molecular FormulaC3Cl2N3NaO3 Nickname (s)Dichloroisocyanuric; acid, sodium salt; 3,5-Dichloro-2-hydroxy-4,6-s-triazinedione sodium salt; Dichloroisocyanuric Acid Sodium Salt; dikonit; simpla; Sodium Dichloroisocyanurate; DCCNA; SDIC; Dichloro-s-triazinetrione sodium salt Molecular weight219.94600 Precise quality218.92100 PSA79.95000 LOGP-0.44740 Prodection Details Appearance and property: white crystalline granule or powders or flakes Density: 2.06 g/cm3 Boiling point: 306.7 C at 760 mmHg Melting point: 225 ° C Flashing Point: DHS 139.3 C Water solubility: 30G/100ML (25 C) Stability: Stable. The Oxidizing agent - contact with combustible material may lead to the fire. The Incompatible with strong outside, strong Oxidizing agents nitrogen with many nitrogen-containing compounds to form explosive nitrogen triiodide. Moisture-sensitive. Storage conditions: 0-6 C Vapor pressure: 7.05 e-05 mmHg at 25 ° C Our Advantages 1. International first-class production capacity (rich inventory, stable supply ability; we have warehouses all over China domestic cities). 2. Top production test equipment 3. Advanced research and development center 4. Strict quality 5. Professional logistics team to ensure the safety of transportation and timely arrival of goods 6. Professional service team (For details, kindly check the Letter of commitment before and after sales in "About Us" from Homepage). Our Factory And Company Our factory advanced production technology and equipment. FactoryCompany Major Exporting Countries Deliver, Shipping And Serving We will provide you with quality products and professional services. You are always welcome to consult us. We will provide you with a comprehensive offer, including quotation, payment, mail, etc. We look forward to your inquiry. Cooperation Cases Production Methods 1. By ammonium chloride and urea together after heating reaction acidification, alkali solution, through chlorination, and then dry. 2. Isocyanuric acid, sodium hydroxide, chlorine gas as raw materials. 3. Sodium hydroxide and cyanuric acid were successively added to the chlorination kettle, and the molar ratio of feed was 2:1. H equals zero at p4. 5~8. 5, temperature 5~1 0 ℃ under continuous chloride, chlorine gas is piped in under two different cyanuric acid chloride, with sodium hydroxide and sodium salt. 4. Reaction of cyanuric acid and chlorine gas.wholesale Swimming Pool Chemical website:http://www.eastchemy.com/basic-organic-chemistry/swimming-pool-chemical/
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  • One Piece Wine Box

    A gift box for wine should not only look nice, but also strong enough and with much protection to ensure that the wines are in good condition when they arrive. High end gift box is also an important part for promotion of wine. Gift boxes for wine could be made of different materials, such as leather, leatherette paper, paper for wrapping and the inserts are made of high end material such as EVA or high density foam.
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    One Piece Wine Box A gift box for wine should not only look nice, but also strong enough and with much protection to ensure that the wines are in good condition when they arrive. High end gift box is also an important part for promotion of wine. Gift boxes for wine could be made of different materials, such as leather, leatherette paper, paper for wrapping and the inserts are made of high end material such as EVA or high density foam. Material: coated paper + greyboard Structure: one piece with a neck Technology: spot color + cold gilding printing https://www.shhcprinting.com/Wine/One-Piece-Wine-Box.shtml
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  • #HiloDefiniciónAlimentaciónHeterotrofaTiposCadenaAlimenticia

    Los heterótrofos pueden ser organótrofos o litótrofos.

    Los organótrofos utilizan compuestos de carbono reducido como fuentes de electrones, como carbohidratos, grasas y proteínas de plantas y animales.

    Los litoheterótrofos usan compuestos inorgánicos, como amonio, nitrito o azufre, para obtener electrones.

    Otra forma de clasificar diferentes heterótrofos es asignándolos como quimiótrofos o fotótrofos. Como ya vimos en el #HiloDefiniciónAlimentaciónHeterotrofa
    Los fotótrofos utilizan la luz para obtener energía y llevar a cabo procesos metabólicos, mientras que los quimiótrofos utilizan la energía obtenida por la oxidación de sustancias químicas de su entorno.

    Los fotoorganoheterótrofos, como las Rhodospirillaceae y las bacterias púrpuras sin azufre, sintetizan compuestos orgánicos mediante la luz solar junto con la oxidación de sustancias orgánicas. Usan compuestos orgánicos para construir estructuras. No fijan dióxido de carbono y aparentemente no tienen el ciclo de Calvin.

    Los quimiolitoheterótrofos como Oceanithermus profundus obtienen energía de la oxidación de compuestos inorgánicos, incluyendo sulfuro de hidrógeno, azufre elemental, tiosulfato e hidrógeno molecular.

    Los mixótrofos (o quimiolitótrofos facultativos) pueden utilizar dióxido de carbono o carbono orgánico como fuente de carbono, lo que significa que los mixótrofos tienen la capacidad de utilizar métodos tanto heterótrofos como autótrofos. Aunque los mixótrofos tienen la capacidad de crecer tanto en condiciones heterótrofas como autótrofas, C. vulgaris tiene mayor biomasa y productividad de lípidos cuando crecen en condiciones heterótrofas en comparación con las autótrofas.

    Los heterótrofos, al consumir compuestos reducidos de carbono, pueden utilizar toda la energía que obtienen de los alimentos (y a menudo oxígeno) para el crecimiento y la reproducción, a diferencia de los autótrofos, que deben utilizar parte de su energía para la fijación de carbono.

    Tanto los heterótrofos como los autótrofos suelen depender de las actividades metabólicas de otros organismos para obtener nutrientes distintos del carbono, incluidos el nitrógeno, el fósforo y el azufre, y pueden morir por falta de alimentos que suministren estos nutrientes. Esto se aplica no solo a los animales y los hongos, sino también a las bacterias.

    Muchos heterótrofos son quimioorganoheterótrofos que utilizan carbono orgánico (por ejemplo la glucosa) como fuente de carbono y sustancias químicas orgánicas (por ejemplo: carbohidratos, lípidos, proteínas) como fuentes de electrones.

    Los heterótrofos funcionan como consumidores: obtienen estos nutrientes de nutrientes saprótrofos, parásitos u holozoicos. Descomponen los compuestos orgánicos complejos (por ejemplo: carbohidratos, grasas y proteínas) producidos por los autótrofos en compuestos más simples (por ejemplo: carbohidratos en glucosa, grasas en ácidos grasos y glicerol y proteínas en aminoácidos). Liberan la energía del O2 oxidando los átomos de carbono e hidrógeno de los carbohidratos, lípidos y proteínas a dióxido de carbono y agua, respectivamente.

    Pueden catabolizar compuestos orgánicos por respiración, fermentación o ambos.

    Los heterótrofos fermentativos son o facultativos o anaerobios que llevan a cabo la fermentación en ambientes de oxígeno bajas, en las que la producción de ATP es comúnmente junto con la fosforilación a nivel de sustrato y la producción de productos finales (por ejemplo, alcohol, CO2, sulfuro).

    Estos productos pueden luego servir como sustratos para otras bacterias en la digestión anaeróbica y convertirse en CO2 y CH4, que es un paso importante para el ciclo del carbono para eliminar los productos orgánicos de fermentación de los ambientes anaeróbicos.

    Los heterótrofos pueden experimentar respiración, en la que la producción de ATP se acopla con la fosforilación oxidativa. Esto conduce a la liberación de desechos de carbono oxidado como el CO2 y desechos reducidos como el H2O, H2S o N2O a la atmósfera. La respiración y la fermentación de los microbios heterótrofos representan una gran parte de la liberación de CO2 a la atmósfera, lo que lo hace disponible para los autótrofos como fuente de nutrientes y las plantas como sustrato de síntesis de celulosa.

    La respiración en los heterótrofos suele ir acompañada de mineralización, el proceso de conversión de compuestos orgánicos en formas inorgánicas. Cuando la fuente de nutrientes orgánicos absorbida por el heterótrofo contiene elementos esenciales como N, S, P además de C, H y O, a menudo se eliminan primero para proceder con la oxidación de nutrientes orgánicos y la producción de ATP a través de la respiración. El S y N en la fuente de carbono orgánico se transforman en H2S y NH4+ mediante desulfurilación y desaminación, respectivamente.

    Los heterótrofos también permiten la desfosforilación como parte de la descomposición. La conversión de S y N de forma orgánica a inorgánica es una parte fundamental del ciclo del nitrógeno y el azufre. El H2S formado a partir de desulfurilación se oxida adicionalmente por litótrofos y fotótrofas, mientras NH4+ formado a partir de desaminación se oxida adicionalmente por litótrofos a las formas disponibles para las plantas. La capacidad de los heterótrofos para mineralizar elementos esenciales es fundamental para la supervivencia de las plantas.

    Como curiosidad. Algunos animales, como los corales, forman relaciones simbióticas con los autótrofos y obtienen carbono orgánico de esta forma. Además, algunas plantas parásitas también se han vuelto total o parcialmente heterótrofas, mientras que las plantas carnívoras consumen animales para aumentar su suministro de nitrógeno sin dejar de ser autótrofas.

    Como última curiosidad. Los animales se clasifican como heterótrofos por ingestión, los hongos se clasifican como heterótrofos por absorción.

    Bibliografía:
    •  «Heterotroph definition». Biology Dictionary. 15 de diciembre de 2016.
    •  Hogg, Stuart (2013). Essential microbiology (2nd ed edición). Wiley-Blackwell. p. 86. ISBN 978-1-118-52726-9. OCLC 823139857.
    • «How Cells Harvest Energy». McGraw-Hill Higher Education. Archivado desde el original el 31 de julio de 2012. Consultado el 10 de octubre de 2010.
    • Cold Spring Harbor Symposia on Quantitative Biology XI. 1946. pp. 302-303.
    •  Wetzel, R.G. (2001). Limnology: Lake and river ecosystems (3rd edición). Academic Press. p. 700.
    • Plumlee, Geoffrey S.; Logsdon, Mark J.; Filipek, L. H. (1997). The environmental geochemistry of mineral deposits (en inglés). pp. 125-137. ISBN 978-1-62949-013-7. OCLC 989865806.
    • Mauseth, James D. (2008). Botany: An introduction to plant biology (4th edición). Jones & Bartlett Publishers. p. 252. ISBN 978-0-7637-5345-0. «heterotroph fix carbon. »
    • Miroshnichenko, M. L.; L'Haridon, S.; Jeanthon, C.; Antipov, A. N.; Kostrikina, N. A.; Tindall, B. J.; Schumann, P.; Spring, S. et al. (2003-05). «Oceanithermus profundus gen. nov., sp. nov., a thermophilic, microaerophilic, facultatively chemolithoheterotrophic bacterium from a deep-sea hydrothermal vent». International Journal of Systematic and Evolutionary Microbiology 53 (Pt 3): 747-752. ISSN 1466-5026. PMID 12807196. doi:10.1099/ijs.0.02367-0.
    • Libes, Susan M. (2009). Introduction to Marine Biogeochemistry (2nd edición). Academic Press. p. 192. ISBN 978-0-12-088530-5.
    • Dworkin, Martin (2006). The prokaryotes: ecophysiology and biochemistry (3rd edición). Springer. p. 988. ISBN 978-0-387-25492-0.
    • Liang, Yanna; Sarkany, Nicolas; Cui, Yi (2009-07). «Biomass and lipid productivities of Chlorella vulgaris under autotrophic, heterotrophic and mixotrophic growth conditions». Biotechnology Letters 31 (7): 1043-1049. ISSN 1573-6776. PMID 19322523. doi:10.1007/s10529-009-9975-7.
    • Schmidt-Rohr, Klaus (11 de febrero de 2020). «Oxygen Is the High-Energy Molecule Powering Complex Multicellular Life: Fundamental Corrections to Traditional Bioenergetics». ACS Omega 5 (5): 2221-2233. ISSN 2470-1343. PMC 7016920. PMID 32064383. doi:10.1021/acsomega.9b03352.
    • Campbell and Reece (2002). Biology (7th edición). Benjamin-Cummings Publishing Co. ISBN 978-0805371710.
    • Mills, A.L. «The role of bacteria in environmental geochemistry».
    •  «Heterotrophic nutrition and control of bacterial density».
    • Gottschalk, Gerhard (2012). Bacterial Metabolism. Springer Series in Microbiology (2 edición). Springer. ISBN 978-0387961538. doi:10.1007/978-1-4612-1072-6.
    • Wade, Bingle (2016). MICB 201: Introductory Environmental Microbiology. pp. 236-250.
    • Kirchman, David L. (2012). Processes in microbial ecology. Oxford University Press. pp. 79-98. ISBN 978-0-19-162421-6. OCLC 777261246.
    • Wikipedia
    #HiloDefiniciónAlimentaciónHeterotrofaTiposCadenaAlimenticia Los heterótrofos pueden ser organótrofos o litótrofos. Los organótrofos utilizan compuestos de carbono reducido como fuentes de electrones, como carbohidratos, grasas y proteínas de plantas y animales. Los litoheterótrofos usan compuestos inorgánicos, como amonio, nitrito o azufre, para obtener electrones. Otra forma de clasificar diferentes heterótrofos es asignándolos como quimiótrofos o fotótrofos. Como ya vimos en el #HiloDefiniciónAlimentaciónHeterotrofa Los fotótrofos utilizan la luz para obtener energía y llevar a cabo procesos metabólicos, mientras que los quimiótrofos utilizan la energía obtenida por la oxidación de sustancias químicas de su entorno. Los fotoorganoheterótrofos, como las Rhodospirillaceae y las bacterias púrpuras sin azufre, sintetizan compuestos orgánicos mediante la luz solar junto con la oxidación de sustancias orgánicas. Usan compuestos orgánicos para construir estructuras. No fijan dióxido de carbono y aparentemente no tienen el ciclo de Calvin. Los quimiolitoheterótrofos como Oceanithermus profundus obtienen energía de la oxidación de compuestos inorgánicos, incluyendo sulfuro de hidrógeno, azufre elemental, tiosulfato e hidrógeno molecular. Los mixótrofos (o quimiolitótrofos facultativos) pueden utilizar dióxido de carbono o carbono orgánico como fuente de carbono, lo que significa que los mixótrofos tienen la capacidad de utilizar métodos tanto heterótrofos como autótrofos. Aunque los mixótrofos tienen la capacidad de crecer tanto en condiciones heterótrofas como autótrofas, C. vulgaris tiene mayor biomasa y productividad de lípidos cuando crecen en condiciones heterótrofas en comparación con las autótrofas. Los heterótrofos, al consumir compuestos reducidos de carbono, pueden utilizar toda la energía que obtienen de los alimentos (y a menudo oxígeno) para el crecimiento y la reproducción, a diferencia de los autótrofos, que deben utilizar parte de su energía para la fijación de carbono. Tanto los heterótrofos como los autótrofos suelen depender de las actividades metabólicas de otros organismos para obtener nutrientes distintos del carbono, incluidos el nitrógeno, el fósforo y el azufre, y pueden morir por falta de alimentos que suministren estos nutrientes. Esto se aplica no solo a los animales y los hongos, sino también a las bacterias. Muchos heterótrofos son quimioorganoheterótrofos que utilizan carbono orgánico (por ejemplo la glucosa) como fuente de carbono y sustancias químicas orgánicas (por ejemplo: carbohidratos, lípidos, proteínas) como fuentes de electrones. Los heterótrofos funcionan como consumidores: obtienen estos nutrientes de nutrientes saprótrofos, parásitos u holozoicos. Descomponen los compuestos orgánicos complejos (por ejemplo: carbohidratos, grasas y proteínas) producidos por los autótrofos en compuestos más simples (por ejemplo: carbohidratos en glucosa, grasas en ácidos grasos y glicerol y proteínas en aminoácidos). Liberan la energía del O2 oxidando los átomos de carbono e hidrógeno de los carbohidratos, lípidos y proteínas a dióxido de carbono y agua, respectivamente. Pueden catabolizar compuestos orgánicos por respiración, fermentación o ambos. Los heterótrofos fermentativos son o facultativos o anaerobios que llevan a cabo la fermentación en ambientes de oxígeno bajas, en las que la producción de ATP es comúnmente junto con la fosforilación a nivel de sustrato y la producción de productos finales (por ejemplo, alcohol, CO2, sulfuro). Estos productos pueden luego servir como sustratos para otras bacterias en la digestión anaeróbica y convertirse en CO2 y CH4, que es un paso importante para el ciclo del carbono para eliminar los productos orgánicos de fermentación de los ambientes anaeróbicos. Los heterótrofos pueden experimentar respiración, en la que la producción de ATP se acopla con la fosforilación oxidativa. Esto conduce a la liberación de desechos de carbono oxidado como el CO2 y desechos reducidos como el H2O, H2S o N2O a la atmósfera. La respiración y la fermentación de los microbios heterótrofos representan una gran parte de la liberación de CO2 a la atmósfera, lo que lo hace disponible para los autótrofos como fuente de nutrientes y las plantas como sustrato de síntesis de celulosa. La respiración en los heterótrofos suele ir acompañada de mineralización, el proceso de conversión de compuestos orgánicos en formas inorgánicas. Cuando la fuente de nutrientes orgánicos absorbida por el heterótrofo contiene elementos esenciales como N, S, P además de C, H y O, a menudo se eliminan primero para proceder con la oxidación de nutrientes orgánicos y la producción de ATP a través de la respiración. El S y N en la fuente de carbono orgánico se transforman en H2S y NH4+ mediante desulfurilación y desaminación, respectivamente. Los heterótrofos también permiten la desfosforilación como parte de la descomposición. La conversión de S y N de forma orgánica a inorgánica es una parte fundamental del ciclo del nitrógeno y el azufre. El H2S formado a partir de desulfurilación se oxida adicionalmente por litótrofos y fotótrofas, mientras NH4+ formado a partir de desaminación se oxida adicionalmente por litótrofos a las formas disponibles para las plantas. La capacidad de los heterótrofos para mineralizar elementos esenciales es fundamental para la supervivencia de las plantas. Como curiosidad. Algunos animales, como los corales, forman relaciones simbióticas con los autótrofos y obtienen carbono orgánico de esta forma. Además, algunas plantas parásitas también se han vuelto total o parcialmente heterótrofas, mientras que las plantas carnívoras consumen animales para aumentar su suministro de nitrógeno sin dejar de ser autótrofas. Como última curiosidad. Los animales se clasifican como heterótrofos por ingestión, los hongos se clasifican como heterótrofos por absorción. Bibliografía: •  «Heterotroph definition». Biology Dictionary. 15 de diciembre de 2016. •  Hogg, Stuart (2013). Essential microbiology (2nd ed edición). Wiley-Blackwell. p. 86. ISBN 978-1-118-52726-9. OCLC 823139857. • «How Cells Harvest Energy». McGraw-Hill Higher Education. Archivado desde el original el 31 de julio de 2012. Consultado el 10 de octubre de 2010. • Cold Spring Harbor Symposia on Quantitative Biology XI. 1946. pp. 302-303. •  Wetzel, R.G. (2001). Limnology: Lake and river ecosystems (3rd edición). Academic Press. p. 700. • Plumlee, Geoffrey S.; Logsdon, Mark J.; Filipek, L. H. (1997). The environmental geochemistry of mineral deposits (en inglés). pp. 125-137. ISBN 978-1-62949-013-7. OCLC 989865806. • Mauseth, James D. (2008). Botany: An introduction to plant biology (4th edición). Jones & Bartlett Publishers. p. 252. ISBN 978-0-7637-5345-0. «heterotroph fix carbon. » • Miroshnichenko, M. L.; L'Haridon, S.; Jeanthon, C.; Antipov, A. N.; Kostrikina, N. A.; Tindall, B. J.; Schumann, P.; Spring, S. et al. (2003-05). «Oceanithermus profundus gen. nov., sp. nov., a thermophilic, microaerophilic, facultatively chemolithoheterotrophic bacterium from a deep-sea hydrothermal vent». International Journal of Systematic and Evolutionary Microbiology 53 (Pt 3): 747-752. ISSN 1466-5026. PMID 12807196. doi:10.1099/ijs.0.02367-0. • Libes, Susan M. (2009). Introduction to Marine Biogeochemistry (2nd edición). Academic Press. p. 192. ISBN 978-0-12-088530-5. • Dworkin, Martin (2006). The prokaryotes: ecophysiology and biochemistry (3rd edición). Springer. p. 988. ISBN 978-0-387-25492-0. • Liang, Yanna; Sarkany, Nicolas; Cui, Yi (2009-07). «Biomass and lipid productivities of Chlorella vulgaris under autotrophic, heterotrophic and mixotrophic growth conditions». Biotechnology Letters 31 (7): 1043-1049. ISSN 1573-6776. PMID 19322523. doi:10.1007/s10529-009-9975-7. • Schmidt-Rohr, Klaus (11 de febrero de 2020). «Oxygen Is the High-Energy Molecule Powering Complex Multicellular Life: Fundamental Corrections to Traditional Bioenergetics». ACS Omega 5 (5): 2221-2233. ISSN 2470-1343. PMC 7016920. PMID 32064383. doi:10.1021/acsomega.9b03352. • Campbell and Reece (2002). Biology (7th edición). Benjamin-Cummings Publishing Co. ISBN 978-0805371710. • Mills, A.L. «The role of bacteria in environmental geochemistry». •  «Heterotrophic nutrition and control of bacterial density». • Gottschalk, Gerhard (2012). Bacterial Metabolism. Springer Series in Microbiology (2 edición). Springer. ISBN 978-0387961538. doi:10.1007/978-1-4612-1072-6. • Wade, Bingle (2016). MICB 201: Introductory Environmental Microbiology. pp. 236-250. • Kirchman, David L. (2012). Processes in microbial ecology. Oxford University Press. pp. 79-98. ISBN 978-0-19-162421-6. OCLC 777261246. • Wikipedia
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  • China Citric Acid Series manufacturers Potassium Citrate 1. Chemical name: mono-hydrous tripotassium,2-hydroxy propane-1,2,3-tricarboxylate potassium citrate. 2. M. F.: K3C6H5O7.H2O 3. M. W.: 324.41 4. Physical properties: White or slightly crystal granular or powder; odorless, cool and salty; easily deliquescent; easily soluble in water or glycerine but almost insoluble in Ethanol; Relative density is 1.98. It will melt and decompose when heated to 230鈩? 5. Quality standard GB14889-94.BP2009. FCC-V .USP32) Name of indexGB14889-94BP2009FCC-VUSP32 AppearanceWhite or light yellow crystal or powderWhite or light yellow crystal or powderWhite or light yellow crystal or powderWhite or light yellow crystal or powder Content(K3C6H5O7) 鈮?99.099.0-101.099.0-100.599.0-100.5 Heavy metal(As Pb) 鈮?0.0010.001-0.001 AS 鈮?0.00030.0001-0.0001 Loss on drying %3.0-6.0-3.0-6.03.0-6.0 Lead--0.0002- Moisture%-4.0-7.0 - Cl 鈮?-0.005 - Sulphate Salt鈮?-0.015 - Qxalates 鈮?-0.03 - Sodium 鈮?-0.3 - AlkalinityPass testPass testPass testPass test Readily Carbonisable Substances-Pass test-- Transparenly and color of sample-Pass test-- Pyrogens-Pass test-- 6. Usage: In food industry, it is used as buffer, chelating agent, stabilizer, antioxidant, emulsifier and flavor. Applied in dairy product銆乯ellies銆?jam銆?meat銆?tinned and pastry. Also used as emulsifier in cheese and fresh-keeping in citrus. In pharmaceutical industry, it is used for curing hypokalimia, potassium deficiency deficiency and alkalization of urine. 7. Packing: In 25kg composite plastic woven/ paper bag with PE liner 8. Storage and transport: It should be stored in a dry and ventilative warehouse and kept away from moisture, heat and poisonous substance. Handled with care, so as to avoid damage to packing bags.China Citric Acid Series manufacturers website:http://www.ltw-ingredients.com/citric-acid-series/
    China Citric Acid Series manufacturers Potassium Citrate 1. Chemical name: mono-hydrous tripotassium,2-hydroxy propane-1,2,3-tricarboxylate potassium citrate. 2. M. F.: K3C6H5O7.H2O 3. M. W.: 324.41 4. Physical properties: White or slightly crystal granular or powder; odorless, cool and salty; easily deliquescent; easily soluble in water or glycerine but almost insoluble in Ethanol; Relative density is 1.98. It will melt and decompose when heated to 230鈩? 5. Quality standard :( GB14889-94.BP2009. FCC-V .USP32) Name of indexGB14889-94BP2009FCC-VUSP32 AppearanceWhite or light yellow crystal or powderWhite or light yellow crystal or powderWhite or light yellow crystal or powderWhite or light yellow crystal or powder Content(K3C6H5O7) 鈮?99.099.0-101.099.0-100.599.0-100.5 Heavy metal(As Pb) 鈮?0.0010.001-0.001 AS 鈮?0.00030.0001-0.0001 Loss on drying %3.0-6.0-3.0-6.03.0-6.0 Lead--0.0002- Moisture%-4.0-7.0 - Cl 鈮?-0.005 - Sulphate Salt鈮?-0.015 - Qxalates 鈮?-0.03 - Sodium 鈮?-0.3 - AlkalinityPass testPass testPass testPass test Readily Carbonisable Substances-Pass test-- Transparenly and color of sample-Pass test-- Pyrogens-Pass test-- 6. Usage: In food industry, it is used as buffer, chelating agent, stabilizer, antioxidant, emulsifier and flavor. Applied in dairy product銆乯ellies銆?jam銆?meat銆?tinned and pastry. Also used as emulsifier in cheese and fresh-keeping in citrus. In pharmaceutical industry, it is used for curing hypokalimia, potassium deficiency deficiency and alkalization of urine. 7. Packing: In 25kg composite plastic woven/ paper bag with PE liner 8. Storage and transport: It should be stored in a dry and ventilative warehouse and kept away from moisture, heat and poisonous substance. Handled with care, so as to avoid damage to packing bags.China Citric Acid Series manufacturers website:http://www.ltw-ingredients.com/citric-acid-series/
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  • Gastroscopy & Colonoscopy Singaporev

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    Gastroscopy & Colonoscopy Singaporev Somerset endoscopy centre Singapore Somerset Imaging Centre is a one stop Medical Imaging Centre provides all the medical imaging that you need including the MRI, CT, Ultrasound, Endoscopy (Gastroscopy and Colonoscopy), 2D and 3D Mammogram, X-ray, Bone Mineral Density Scan, Body Composition Scan, Treadmill Exercise Test and ECG. 1) Heart Evaluation 2) Medical Imaging 3) Endoscopy 4) GP Consultation Services We offer 1) CT SCAN 2) MRI Scan 3) Mammogram 4) X-Ray 5) MR MPI 6) CTA 7) Endoscopy 8) Ultrasound 9) ECG, Blood tests Book an Appointment with us https://www.hsig.org/
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  • #HiloHaroldVarmus

    Harold Eliot Varmus (born December 18, 1939) is an American Nobel Prize-winning scientist who was director of the National Institutes of Health from 1993 to 1999 and the 14th Director of the National Cancer Institute from 2010 to 2015, a post to which he was appointed by President Barack Obama. He was a co-recipient (along with J. Michael Bishop) of the 1989 Nobel Prize in Physiology or Medicine for discovery of the cellular origin of retroviral oncogenes. He is currently the Lewis Thomas University Professor of Medicine at Weill Cornell Medicine and a senior associate at the New York Genome Center.

    Varmus was born to Beatrice, a social service worker, and Frank Varmus, a physician, Jewish parents of Eastern European descent, in Oceanside, New York. In 1957, he graduated from Freeport High School in Freeport, New York, and enrolled at Amherst College, intending to follow in his father's footsteps as a medical doctor, but eventually graduating with a B.A. in English literature. He went on to earn a graduate degree in English at Harvard University in 1962 before changing his mind once again and applying to medical schools. He was twice rejected from Harvard Medical School. That same year, he entered the Columbia University College of Physicians and Surgeons and later worked at a missionary hospital in Bareilly, India, and the Columbia Presbyterian Medical Center. As an alternative to serving militarily in the Vietnam War, Varmus joined the Public Health Service at the National Institutes of Health in 1968. Working under Ira Pastan, he researched the regulation of bacterial gene expression by cyclic AMP. In 1970, he began postdoctoral research in Bishop's lab at University of California, San Francisco.

    To fulfill his national service obligations during the Vietnam War, Varmus became a member of the commissioned corps of the Public Health Service, working as a Clinical Associate in the laboratory of Ira Pastan at the National Institutes of Health from 1968 to 1970. During this first period of laboratory research, he and Pastan and their colleagues described aspects of the mechanism by which the lac operon of E. coli is regulated transcriptionally by cyclic AMP.[6] In 1970, he and his wife, Constance Casey, moved to San Francisco, where he began post-doctoral studies with Michael Bishop at University of California, San Francisco under a fellowship from the California Division of the American Cancer Society. Appointed as an assistant professor in the UCSF Department of Microbiology and Immunology in 1972, he was promoted to professor in 1979 and became an American Cancer Society Research Professor in 1984.

    During the course of his years at UCSF (1970 to 1993), Varmus's scientific work was focused principally on the mechanisms by which retroviruses replicate, cause cancers in animals, and produce cancer-like changes in cultured cells. Much of this work was conducted jointly with Michael Bishop in a notably long scientific partnership. Their best-known accomplishment was the identification of a cellular gene (c-src) that gave rise to the v-src oncogene of Rous Sarcoma Virus, a cancer-causing virus first isolated from a chicken sarcoma by Peyton Rous in 1910. Their discovery triggered the identification of many other cellular proto-oncogenes—progenitors of viral oncogenes and targets for mutations that drive human cancers. Much of this work and its consequences are described in his Nobel lecture and Bishop's and in numerous histories of cancer research.

    Other significant components of Varmus's scientific work over the past four and a half decades include descriptions of the mechanisms by which retroviral DNA is synthesized and integrated into chromosomes; discovery of the Wnt-1 proto-oncogene with Roel Nusse elucidation of aspects of the replicatio cycle of hepatitis B virus (with Donald Ganem); discovery of ribosomal frameshifting to make retroviral proteins (with Tyler Jacks); isolation of a cellular receptor for avian retroviruses (with John Young and Paul Bates); characterization of mutations of the epidermal growth factor receptor gene in human lung cancers, including a common mutation that confers drug resistance (with William Pao); and generation of numerous mouse models of human cancer. Notably, Varmus continued to conduct or direct laboratory work throughout his service in leadership positions at the NIH, MSKCC, and NCI.

    References:
     "President Obama to Appoint Harold Varmus, M.D." National Cancer Institute. Archived from the original on May 27, 2010.

    NIH Directors". 2015-02-11.

    Varmus, H.E.; Perlman, R.L.; Pastan, I. (1970). "Regulation of lac messenger ribonucleic acid synthesis by cyclic adenosine 3'-5' monophosphate and glucose". J. Biol. Chem. 245 (9): 2259–67. doi:10.1016/S0021-9258(18)63147-3. PMID 4315149.

    Stehelin, D.; Varmus, H. E.; Bishop, J. M.; Vogt, P. K. (1976-03-11). "DNA related to the transforming gene(s) of avian sarcoma viruses is present in normal avian DNA". Nature. 260 (5547): 170–173. Bibcode:1976Natur.260..170S. doi:10.1038/260170a0. PMID 176594. S2CID 4178400.

    "Nobel Lecture by Harold E. Varmus – Media Player at Nobelprize.org". www.nobelprize.org. Retrieved 2016-03-09.

    "Nobel Lecture by J. Michael Bishop – Media Player at Nobelprize.org". www.nobelprize.org. Retrieved 2016-03-09.

    Mukherjee, S. (2010). The Emperor of All Maladies: A Biography of Cancer. New York: Scribner. pp. 360–380.

    Varmus, H. (1988-06-10). "Retroviruses". Science. 240 (4858): 1427–1435. Bibcode:1988Sci...240.1427V. doi:10.1126/science.3287617. ISSN 0036-8075. PMID 3287617.

    Brown, P. O.; Bowerman, B.; Varmus, H. E.; Bishop, J. M. (1987-05-08). "Correct integration of retroviral DNA in vitro". Cell. 49 (3): 347–356. doi:10.1016/0092-8674(87)90287-x. ISSN 0092-8674. PMID 3032450. S2CID 35523639.

    Nusse, R.; Varmus, H. E. (1982-11-01). "Many tumors induced by the mouse mammary tumor virus contain a provirus integrated in the same region of the host genome". Cell. 31 (1): 99–109. doi:10.1016/0092-8674(82)90409-3. ISSN 0092-8674. PMID 6297757. S2CID 46024617.

    Nusse, Roel; Varmus, Harold (2012-06-13). "Three decades of Wnts: a personal perspective on how a scientific field developed". The EMBO Journal. 31 (12): 2670–2684. doi:10.1038/emboj.2012.146. PMC 3380217. PMID 22617420.

    Seeger, C.; Ganem, D.; Varmus, H. (1986). "Biochemical and genetic evidence for the hepatitis B virus replication strategy". Science. 232 (4749): 477–484. Bibcode:1986Sci...232..477S. doi:10.1126/science.3961490. PMID 3961490.

    Jacks, T.; Varmus, H.E. (1985). "Expression of the Rous sarcoma virus pol gene by ribosomal frameshifting". Science. 230 (4731): 1237–42. Bibcode:1985Sci...230.1237J. doi:10.1126/science.2416054. PMID 2416054.

    Bates, P; Young, JA; Varmus, HE (1993). "A receptor for subgroup A Rous sarcoma virus is related to the low density lipoprotein receptor". Cell. 74 (6): 1043–51. doi:10.1016/0092-8674(93)90726-7. PMID 8402880. S2CID 10787640.

    Pao, W.; Miller, V.; Zakowski, M.; Doherty, J.; Politi, K.; Sarkaria, I.; Singh, B.; Heelan, B.; Rusch, V.; Fulton, L.; Mardis, E.; Kupfer, D; Wilson, R.; Kris, M.; Varmus (2004). "never smokers" and are associated with sensitivity of tumors to gefitinib and erlotinib". Proceedings of the National Academy of Sciences. 101 (36): 13306–11. doi:10.1073/pnas.0405220101. PMC 516528. PMID 15329413.

    Bishop, J.M.; Kirschner, M.; Varmus, H.E. (1993). "Policy Forum: Science and the New Administration". Science. 259 (5094): 444–445. doi:10.1126/science.8424162. PMID 8424162.

    Varmus, Harold (2009). The Art and Politics of Science. W.W. Norton. pp. 140–196.

    Varmus, Harold (2006). AAAS Bulletin. pp. 6–11, Vol. LIX, No.4.

    Varmus, H. Making PEPFAR: A Triumph of Medical Diplomacy. Science & Diplomacy 2(4) December, 2013.

    Nicholas Thompson: Harold Varmus Endorses Obama, Wired, February 03, 2008

    "Obama Chooses Science Team for Planetary Survival, Prosperity". NBC Southern California. Retrieved 2016-03-10.

    "President Obama to Appoint Harold Varmus, M.D., to Lead the National Cancer Institute". nursezone.com. Retrieved 2016-03-10.

    Gracias por leer
    Que la ciencia y la fuerza os acompañe
    #HiloHaroldVarmus Harold Eliot Varmus (born December 18, 1939) is an American Nobel Prize-winning scientist who was director of the National Institutes of Health from 1993 to 1999 and the 14th Director of the National Cancer Institute from 2010 to 2015, a post to which he was appointed by President Barack Obama. He was a co-recipient (along with J. Michael Bishop) of the 1989 Nobel Prize in Physiology or Medicine for discovery of the cellular origin of retroviral oncogenes. He is currently the Lewis Thomas University Professor of Medicine at Weill Cornell Medicine and a senior associate at the New York Genome Center. Varmus was born to Beatrice, a social service worker, and Frank Varmus, a physician, Jewish parents of Eastern European descent, in Oceanside, New York. In 1957, he graduated from Freeport High School in Freeport, New York, and enrolled at Amherst College, intending to follow in his father's footsteps as a medical doctor, but eventually graduating with a B.A. in English literature. He went on to earn a graduate degree in English at Harvard University in 1962 before changing his mind once again and applying to medical schools. He was twice rejected from Harvard Medical School. That same year, he entered the Columbia University College of Physicians and Surgeons and later worked at a missionary hospital in Bareilly, India, and the Columbia Presbyterian Medical Center. As an alternative to serving militarily in the Vietnam War, Varmus joined the Public Health Service at the National Institutes of Health in 1968. Working under Ira Pastan, he researched the regulation of bacterial gene expression by cyclic AMP. In 1970, he began postdoctoral research in Bishop's lab at University of California, San Francisco. To fulfill his national service obligations during the Vietnam War, Varmus became a member of the commissioned corps of the Public Health Service, working as a Clinical Associate in the laboratory of Ira Pastan at the National Institutes of Health from 1968 to 1970. During this first period of laboratory research, he and Pastan and their colleagues described aspects of the mechanism by which the lac operon of E. coli is regulated transcriptionally by cyclic AMP.[6] In 1970, he and his wife, Constance Casey, moved to San Francisco, where he began post-doctoral studies with Michael Bishop at University of California, San Francisco under a fellowship from the California Division of the American Cancer Society. Appointed as an assistant professor in the UCSF Department of Microbiology and Immunology in 1972, he was promoted to professor in 1979 and became an American Cancer Society Research Professor in 1984. During the course of his years at UCSF (1970 to 1993), Varmus's scientific work was focused principally on the mechanisms by which retroviruses replicate, cause cancers in animals, and produce cancer-like changes in cultured cells. Much of this work was conducted jointly with Michael Bishop in a notably long scientific partnership. Their best-known accomplishment was the identification of a cellular gene (c-src) that gave rise to the v-src oncogene of Rous Sarcoma Virus, a cancer-causing virus first isolated from a chicken sarcoma by Peyton Rous in 1910. Their discovery triggered the identification of many other cellular proto-oncogenes—progenitors of viral oncogenes and targets for mutations that drive human cancers. Much of this work and its consequences are described in his Nobel lecture and Bishop's and in numerous histories of cancer research. Other significant components of Varmus's scientific work over the past four and a half decades include descriptions of the mechanisms by which retroviral DNA is synthesized and integrated into chromosomes; discovery of the Wnt-1 proto-oncogene with Roel Nusse elucidation of aspects of the replicatio cycle of hepatitis B virus (with Donald Ganem); discovery of ribosomal frameshifting to make retroviral proteins (with Tyler Jacks); isolation of a cellular receptor for avian retroviruses (with John Young and Paul Bates); characterization of mutations of the epidermal growth factor receptor gene in human lung cancers, including a common mutation that confers drug resistance (with William Pao); and generation of numerous mouse models of human cancer. Notably, Varmus continued to conduct or direct laboratory work throughout his service in leadership positions at the NIH, MSKCC, and NCI. References:  "President Obama to Appoint Harold Varmus, M.D." National Cancer Institute. Archived from the original on May 27, 2010. NIH Directors". 2015-02-11. Varmus, H.E.; Perlman, R.L.; Pastan, I. (1970). "Regulation of lac messenger ribonucleic acid synthesis by cyclic adenosine 3'-5' monophosphate and glucose". J. Biol. Chem. 245 (9): 2259–67. doi:10.1016/S0021-9258(18)63147-3. PMID 4315149. Stehelin, D.; Varmus, H. E.; Bishop, J. M.; Vogt, P. K. (1976-03-11). "DNA related to the transforming gene(s) of avian sarcoma viruses is present in normal avian DNA". Nature. 260 (5547): 170–173. Bibcode:1976Natur.260..170S. doi:10.1038/260170a0. PMID 176594. S2CID 4178400. "Nobel Lecture by Harold E. Varmus – Media Player at Nobelprize.org". www.nobelprize.org. Retrieved 2016-03-09. "Nobel Lecture by J. Michael Bishop – Media Player at Nobelprize.org". www.nobelprize.org. Retrieved 2016-03-09. Mukherjee, S. (2010). The Emperor of All Maladies: A Biography of Cancer. New York: Scribner. pp. 360–380. Varmus, H. (1988-06-10). "Retroviruses". Science. 240 (4858): 1427–1435. Bibcode:1988Sci...240.1427V. doi:10.1126/science.3287617. ISSN 0036-8075. PMID 3287617. Brown, P. O.; Bowerman, B.; Varmus, H. E.; Bishop, J. M. (1987-05-08). "Correct integration of retroviral DNA in vitro". Cell. 49 (3): 347–356. doi:10.1016/0092-8674(87)90287-x. ISSN 0092-8674. PMID 3032450. S2CID 35523639. Nusse, R.; Varmus, H. E. (1982-11-01). "Many tumors induced by the mouse mammary tumor virus contain a provirus integrated in the same region of the host genome". Cell. 31 (1): 99–109. doi:10.1016/0092-8674(82)90409-3. ISSN 0092-8674. PMID 6297757. S2CID 46024617. Nusse, Roel; Varmus, Harold (2012-06-13). "Three decades of Wnts: a personal perspective on how a scientific field developed". The EMBO Journal. 31 (12): 2670–2684. doi:10.1038/emboj.2012.146. PMC 3380217. PMID 22617420. Seeger, C.; Ganem, D.; Varmus, H. (1986). "Biochemical and genetic evidence for the hepatitis B virus replication strategy". Science. 232 (4749): 477–484. Bibcode:1986Sci...232..477S. doi:10.1126/science.3961490. PMID 3961490. Jacks, T.; Varmus, H.E. (1985). "Expression of the Rous sarcoma virus pol gene by ribosomal frameshifting". Science. 230 (4731): 1237–42. Bibcode:1985Sci...230.1237J. doi:10.1126/science.2416054. PMID 2416054. Bates, P; Young, JA; Varmus, HE (1993). "A receptor for subgroup A Rous sarcoma virus is related to the low density lipoprotein receptor". Cell. 74 (6): 1043–51. doi:10.1016/0092-8674(93)90726-7. PMID 8402880. S2CID 10787640. Pao, W.; Miller, V.; Zakowski, M.; Doherty, J.; Politi, K.; Sarkaria, I.; Singh, B.; Heelan, B.; Rusch, V.; Fulton, L.; Mardis, E.; Kupfer, D; Wilson, R.; Kris, M.; Varmus (2004). "never smokers" and are associated with sensitivity of tumors to gefitinib and erlotinib". Proceedings of the National Academy of Sciences. 101 (36): 13306–11. doi:10.1073/pnas.0405220101. PMC 516528. PMID 15329413. Bishop, J.M.; Kirschner, M.; Varmus, H.E. (1993). "Policy Forum: Science and the New Administration". Science. 259 (5094): 444–445. doi:10.1126/science.8424162. PMID 8424162. Varmus, Harold (2009). The Art and Politics of Science. W.W. Norton. pp. 140–196. Varmus, Harold (2006). AAAS Bulletin. pp. 6–11, Vol. LIX, No.4. Varmus, H. Making PEPFAR: A Triumph of Medical Diplomacy. Science & Diplomacy 2(4) December, 2013. Nicholas Thompson: Harold Varmus Endorses Obama, Wired, February 03, 2008 "Obama Chooses Science Team for Planetary Survival, Prosperity". NBC Southern California. Retrieved 2016-03-10. "President Obama to Appoint Harold Varmus, M.D., to Lead the National Cancer Institute". nursezone.com. Retrieved 2016-03-10. Gracias por leer Que la ciencia y la fuerza os acompañe
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  • Bayesian Optimization for Materials Design with Mixed Quantitative and Qualitative Variables.

    Abstract
    Although Bayesian Optimization (BO) has been employed for accelerating materials design in computational materials engineering, existing works are restricted to problems with quantitative variables. However, real designs of materials systems involve both qualitative and quantitative design variables representing material compositions, microstructure morphology, and processing conditions. For mixed-variable problems, existing Bayesian Optimization (BO) approaches represent qualitative factors by dummy variables first and then fit a standard Gaussian process (GP) model with numerical variables as the surrogate model. This approach is restrictive theoretically and fails to capture complex correlations between qualitative levels. We present in this paper the integration of a novel latent-variable (LV) approach for mixed-variable GP modeling with the BO framework for materials design. LVGP is a fundamentally different approach that maps qualitative design variables to underlying numerical LV in GP, which has strong physical justification. It provides flexible parameterization and representation of qualitative factors and shows superior modeling accuracy compared to the existing methods. We demonstrate our approach through testing with numerical examples and materials design examples. The chosen materials design examples represent two different scenarios, one on concurrent materials selection and microstructure optimization for optimizing the light absorption of a quasi-random solar cell, and another on combinatorial search of material constitutes for optimal Hybrid Organic-Inorganic Perovskite (HOIP) design. It is found that in all test examples the mapped LVs provide intuitive visualization and substantial insight into the nature and effects of the qualitative factors. Though materials designs are used as examples, the method presented is generic and can be utilized for other mixed variable design optimization problems that involve expensive physics-based simulations.

    Introduction
    With advances in computational engineering, materials design and discovery have been increasingly viewed as optimization problems with the goal of achieving desired material properties or device performance1,2,3. One challenge of designing new materials systems is the co-existence of qualitative and quantitative design variables associated with material compositions, microstructure morphology, and processing conditions. While microstructure morphology can be described using quantitative, variables such as those associated with correlation function4, descriptors3,5,6, and spectral density functions1,2, many composition and processing conditions are discrete and qualitative by nature. For example, in polymer nanocomposite design, there are numerous choices of material constituents (e.g., the types of filler and matrix) and processing conditions (e.g., the type of surface treatment); each combination follows drastically different physical mechanisms with significant impact on the overall properties3,7. As illustrated in Fig. 1, the existence of both quantitative and qualitative material design variables results in multiple disjointed regions in the property/performance space. The combinatorial nature poses additional challenges in materials modeling and the search for optimal solution.
    Bayesian Optimization for Materials Design with Mixed Quantitative and Qualitative Variables. Abstract Although Bayesian Optimization (BO) has been employed for accelerating materials design in computational materials engineering, existing works are restricted to problems with quantitative variables. However, real designs of materials systems involve both qualitative and quantitative design variables representing material compositions, microstructure morphology, and processing conditions. For mixed-variable problems, existing Bayesian Optimization (BO) approaches represent qualitative factors by dummy variables first and then fit a standard Gaussian process (GP) model with numerical variables as the surrogate model. This approach is restrictive theoretically and fails to capture complex correlations between qualitative levels. We present in this paper the integration of a novel latent-variable (LV) approach for mixed-variable GP modeling with the BO framework for materials design. LVGP is a fundamentally different approach that maps qualitative design variables to underlying numerical LV in GP, which has strong physical justification. It provides flexible parameterization and representation of qualitative factors and shows superior modeling accuracy compared to the existing methods. We demonstrate our approach through testing with numerical examples and materials design examples. The chosen materials design examples represent two different scenarios, one on concurrent materials selection and microstructure optimization for optimizing the light absorption of a quasi-random solar cell, and another on combinatorial search of material constitutes for optimal Hybrid Organic-Inorganic Perovskite (HOIP) design. It is found that in all test examples the mapped LVs provide intuitive visualization and substantial insight into the nature and effects of the qualitative factors. Though materials designs are used as examples, the method presented is generic and can be utilized for other mixed variable design optimization problems that involve expensive physics-based simulations. Introduction With advances in computational engineering, materials design and discovery have been increasingly viewed as optimization problems with the goal of achieving desired material properties or device performance1,2,3. One challenge of designing new materials systems is the co-existence of qualitative and quantitative design variables associated with material compositions, microstructure morphology, and processing conditions. While microstructure morphology can be described using quantitative, variables such as those associated with correlation function4, descriptors3,5,6, and spectral density functions1,2, many composition and processing conditions are discrete and qualitative by nature. For example, in polymer nanocomposite design, there are numerous choices of material constituents (e.g., the types of filler and matrix) and processing conditions (e.g., the type of surface treatment); each combination follows drastically different physical mechanisms with significant impact on the overall properties3,7. As illustrated in Fig. 1, the existence of both quantitative and qualitative material design variables results in multiple disjointed regions in the property/performance space. The combinatorial nature poses additional challenges in materials modeling and the search for optimal solution.
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  • Watch your language! Linguistic factors contributing to COVID-19 spread.

    Authors: Natalie Grant & Lena Burkel, students of the European Master’s in Clinical Linguistics & Adrià Rofes, assistant professor of neurolinguistics at the University of Groningen

    By now, we’re all experts in the common symptoms of the oh so omnipresent COVID-19 – say, for example, dry coughing, fever, and loss of smell (Sauer, 2021). While we’re all hyper-vigilant about these symptoms, a new factor behind the spread of this virus may be on the rise: language. That’s right: new research suggests that the way we speak may modulate the spread of COVID-19 (Georgiou et al., 2021).

    As we know, COVID-19 is a respiratory disease and its transmission depends on tiny droplets or liquid particles that are produced during any respiratory activity, such as breathing, coughing, or talking. These droplets may then be inhaled by a person standing close by, and the cycle continues.

    Figure 1: droplet transmission. Source: istockphoto
    A study from Asadi et al. (2020) found that even just breathing and speaking can affect the number of droplets emitted. But that’s not all: they found that even more particles can be emitted when speaking and breathing over time in comparison to coughing and sneezing – just another good reason to always put on that mask! With speech and communication being fundamental parts of the human condition, it’s no wonder that researchers are interested in its role in respiratory disease transmission.

    Considering that we possibly emit infectious droplets by the utterances we make, a study published back in 2003 in the Lancet already drew connections between the SARS virus (COVID – 19’s deadlier, but less contagious older sister) and aspiration among English and Japanese speakers.

    Adding to this research, Asadi et al. (2020) also stressed the importance of speech sound characteristics in different languages in regards to respiratory disease transmission:

    Aspiration can be observed in sounds such as /p/ where the air flow is shortly stopped before uttering the sound. We can imagine it like a “puff” of air. These puffs release more droplets and have therefore been assumed to contribute to the increased spread of respiratory diseases. Since the publication of the aforementioned Lancet article, however, the role of aspiration in respiratory disease transmission has been mixed.Iin fact, current studies on COVID-19 show that aspiration isn’t that significant of a factor after all (Georgiou et al., 2021).

    Another aspect is voicedness – voiced speech sounds include vowels and nasals plus a few consonants like /b/, /g/ and /d/. Asadi et al. (2020) looked at voicedness and found that the vowel /i/ (like for example in “need” or “sea”) produced more particles in comparison to vowels like /a/ and /u/. Indeed, all vowels seem to be better conduits for transmission when compared to consonants, because of their voiced quality.

    These same researchers also found a correlation between the vowel/consonant ratio of a language and particle emission. We can take an example from a European language: Italian has a comparatively high vowel density (48%) when compared to English, German, Spanish and French, meaning almost every second letter is a vowel (Duden 2020). In fact, the most common vowel in Italian is /i/. This factor alone, however, is certainly not the only reason why Italy has been one of the hardest hit European countries. A significantly long-life expectancy (meaning lots of old people), an overly dense population, and a smaller perception of personal space, could have all contributed to the swift spread of COVID-19 in the country (Bellegoni, 2020).

    What does seem to make a difference, though, is amplitude. Amplitude can be thought of as the loudness of our speech. And research shows: the louder the voice, the higher the number of droplets (Asadi et al., 2020). One example that made headlines was covered in a study from Hamner et al. (2020), who reported on an account from Washington state where one individual infected with COVID-19 infected 52 others at a 2 ½ hour choir rehearsal. Two people died. As a result, many countries followed suit by prohibiting events requiring “loud” talking or singing such as church services, concerts, and theater. A question that follows is whether individuals who speak louder, or languages that are commonly spoken in a louder manner may have higher infection rates.

    Despite these interesting linguistic arguments, as of today, there just isn’t enough evidence to pinpoint that certain languages are better at transmitting the virus than others. Needless to say, there are many non-linguistic factors in the mix (e.g., the source of transmission, such as touching infected surfaces and then the eyes or nose, (Georgiou et al., 2021) or average distance between speakers, (Asadi et al., 2020)). Now, when it comes to language one thing seems evident: it’s not what you say, but how you say it.

    References
    Asadi, S., Wexler, A. S., Cappa, C. D., Barreda, S., Bouvier, N. M., & Ristenpart, W. D. (2020). Effect of voicing and articulation manner on aerosol particle emission during human speech. PLOS ONE, 15(1), e0227699. doi: 10.1371/journal.pone.0227699

    Belligoni, S. (2020, March 26). 5 reasons the coronavirus hit Italy so hard. The Conversation.

    Duden. (2020). Kleines Kuriositätenkabinett der deutschen Sprache [Eng.: Small cabinet of curiosities of the German Language]. Bibliographisches Institut GmbH.

    Georgiou, G. P., Georgiou, C., & Kilani, A (2021). How the language we speak determines the transmission of COVID-19. Irish Journal of Medical Science (1971-), 1-6. doi: 10.1007/s11845-020-02500-3

    Hamner, L., Dubbel, P., Capron, I., Ross, A., Jordan, A., Lee, J., Lynn, J., Ball, A., Narwal, S., Russell, S., Patrick, D., & Leibrand, H. (2020). High SARS-CoV-2 Attack Rate Following Exposure at a Choir Practice — Skagit County, Washington, March 2020. MMWR. Morbidity and Mortality Weekly Report, 69(19), 606–610. doi: 10.15585/mmwr.mm6919e6

    Inouye, S. (2003). SARS transmission: language and droplet production. The Lancet, 362(9378), 170. doi: 10.1016/s0140-6736(03)13874-3

    Sauer, L. M. (2021, April 06). What Is Coronavirus? Johns Hopkins Medicine.
    Watch your language! Linguistic factors contributing to COVID-19 spread. Authors: Natalie Grant & Lena Burkel, students of the European Master’s in Clinical Linguistics & Adrià Rofes, assistant professor of neurolinguistics at the University of Groningen By now, we’re all experts in the common symptoms of the oh so omnipresent COVID-19 – say, for example, dry coughing, fever, and loss of smell (Sauer, 2021). While we’re all hyper-vigilant about these symptoms, a new factor behind the spread of this virus may be on the rise: language. That’s right: new research suggests that the way we speak may modulate the spread of COVID-19 (Georgiou et al., 2021). As we know, COVID-19 is a respiratory disease and its transmission depends on tiny droplets or liquid particles that are produced during any respiratory activity, such as breathing, coughing, or talking. These droplets may then be inhaled by a person standing close by, and the cycle continues. Figure 1: droplet transmission. Source: istockphoto A study from Asadi et al. (2020) found that even just breathing and speaking can affect the number of droplets emitted. But that’s not all: they found that even more particles can be emitted when speaking and breathing over time in comparison to coughing and sneezing – just another good reason to always put on that mask! With speech and communication being fundamental parts of the human condition, it’s no wonder that researchers are interested in its role in respiratory disease transmission. Considering that we possibly emit infectious droplets by the utterances we make, a study published back in 2003 in the Lancet already drew connections between the SARS virus (COVID – 19’s deadlier, but less contagious older sister) and aspiration among English and Japanese speakers. Adding to this research, Asadi et al. (2020) also stressed the importance of speech sound characteristics in different languages in regards to respiratory disease transmission: Aspiration can be observed in sounds such as /p/ where the air flow is shortly stopped before uttering the sound. We can imagine it like a “puff” of air. These puffs release more droplets and have therefore been assumed to contribute to the increased spread of respiratory diseases. Since the publication of the aforementioned Lancet article, however, the role of aspiration in respiratory disease transmission has been mixed.Iin fact, current studies on COVID-19 show that aspiration isn’t that significant of a factor after all (Georgiou et al., 2021). Another aspect is voicedness – voiced speech sounds include vowels and nasals plus a few consonants like /b/, /g/ and /d/. Asadi et al. (2020) looked at voicedness and found that the vowel /i/ (like for example in “need” or “sea”) produced more particles in comparison to vowels like /a/ and /u/. Indeed, all vowels seem to be better conduits for transmission when compared to consonants, because of their voiced quality. These same researchers also found a correlation between the vowel/consonant ratio of a language and particle emission. We can take an example from a European language: Italian has a comparatively high vowel density (48%) when compared to English, German, Spanish and French, meaning almost every second letter is a vowel (Duden 2020). In fact, the most common vowel in Italian is /i/. This factor alone, however, is certainly not the only reason why Italy has been one of the hardest hit European countries. A significantly long-life expectancy (meaning lots of old people), an overly dense population, and a smaller perception of personal space, could have all contributed to the swift spread of COVID-19 in the country (Bellegoni, 2020). What does seem to make a difference, though, is amplitude. Amplitude can be thought of as the loudness of our speech. And research shows: the louder the voice, the higher the number of droplets (Asadi et al., 2020). One example that made headlines was covered in a study from Hamner et al. (2020), who reported on an account from Washington state where one individual infected with COVID-19 infected 52 others at a 2 ½ hour choir rehearsal. Two people died. As a result, many countries followed suit by prohibiting events requiring “loud” talking or singing such as church services, concerts, and theater. A question that follows is whether individuals who speak louder, or languages that are commonly spoken in a louder manner may have higher infection rates. Despite these interesting linguistic arguments, as of today, there just isn’t enough evidence to pinpoint that certain languages are better at transmitting the virus than others. Needless to say, there are many non-linguistic factors in the mix (e.g., the source of transmission, such as touching infected surfaces and then the eyes or nose, (Georgiou et al., 2021) or average distance between speakers, (Asadi et al., 2020)). Now, when it comes to language one thing seems evident: it’s not what you say, but how you say it. References Asadi, S., Wexler, A. S., Cappa, C. D., Barreda, S., Bouvier, N. M., & Ristenpart, W. D. (2020). Effect of voicing and articulation manner on aerosol particle emission during human speech. PLOS ONE, 15(1), e0227699. doi: 10.1371/journal.pone.0227699 Belligoni, S. (2020, March 26). 5 reasons the coronavirus hit Italy so hard. The Conversation. Duden. (2020). Kleines Kuriositätenkabinett der deutschen Sprache [Eng.: Small cabinet of curiosities of the German Language]. Bibliographisches Institut GmbH. Georgiou, G. P., Georgiou, C., & Kilani, A (2021). How the language we speak determines the transmission of COVID-19. Irish Journal of Medical Science (1971-), 1-6. doi: 10.1007/s11845-020-02500-3 Hamner, L., Dubbel, P., Capron, I., Ross, A., Jordan, A., Lee, J., Lynn, J., Ball, A., Narwal, S., Russell, S., Patrick, D., & Leibrand, H. (2020). High SARS-CoV-2 Attack Rate Following Exposure at a Choir Practice — Skagit County, Washington, March 2020. MMWR. Morbidity and Mortality Weekly Report, 69(19), 606–610. doi: 10.15585/mmwr.mm6919e6 Inouye, S. (2003). SARS transmission: language and droplet production. The Lancet, 362(9378), 170. doi: 10.1016/s0140-6736(03)13874-3 Sauer, L. M. (2021, April 06). What Is Coronavirus? Johns Hopkins Medicine.
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  • For The First Time, Scientists Have Performed Atom Interferometry in Space.

    To make some of the most precise measurements we can of the world around us, scientists tend to go small - right down to the atomic scale, using a technique called atom interferometry.

    Now, for the first time, scientists have performed this kind of measurement in space, using a sounding rocket specially designed to carry science payloads into low-Earth space.

    It's a significant step towards being able to perform matter-wave interferometry in space, for science applications that range from fundamental physics to navigation.

    "We have established the technological basis for atom interferometry on board of a sounding rocket and demonstrated that such experiments are not only possible on Earth, but also in space," said physicist Patrick Windpassinger of Johannes Gutenberg University Mainz in Germany.

    Interferometry is a relatively simple in concept. You take two identical waves, separate them, recombine them, and use the small difference between - called a phase shift - to measure the force that caused that distance.

    This is called an interference pattern. A famous example is LIGO's light interferometer that measures gravitational waves: A beam of light is split down two tunnels miles long, bounced off mirrors and recombined. The resulting interference pattern can be used to detect the gravitational waves caused by colliding black holes millions of light-years away.

    Atom interferometry, harnessing the wave-like behavior of atoms, is a little trickier to achieve, but has the advantage of a much smaller apparatus. It would be very useful in space, where it could be used to measure things like gravity to a high level of precision; so, a team of German researchers has been working for years to try to make it happen.

    The first step is to create a state of matter called a Bose-Einstein condensate. These are formed from atoms cooled to just a fraction above absolute zero (but not reaching absolute zero, at which point atoms stop moving). This causes them to sink to their lowest-energy state, moving extremely slowly, and overlapping in quantum superposition - producing a high density cloud of atoms that acts like one 'super atom' or matter wave.

    This is an ideal starting point for interferometry, because the atoms are all behaving identically, and the team achieved the creation of a Bose-Einstein condensate in space for the first time using their sounding rocket in 2017, with a gas of rubidium atoms.

    "For us, this ultracold ensemble represented a very promising starting point for atom interferometry," Windpassinger said.

    For the next stage of their research, they had to separate and recombine the superimposed atoms. Once again, the researchers created their rubidium Bose-Einstein condensate, but this time they used lasers to irradiate the gas, causing the atoms to separate, then come back together in superposition.

    interference
    Interference patterns observed in the Bose-Einstein condensate. (Lachmann et al., Nat. Commun., 2021)

    The resulting interference pattern showed a clear influence from the microgravity environment of the sounding rocket, suggesting that with a bit of refinement, the technique could be used to measure this environment to high precision.

    The next step of the research, planned for 2022 and 2023, is to try the test again using separate Bose-Einstein condensates of rubidium and potassium to observe their acceleration under free fall.

    Since rubidium and potassium atoms have different masses, this experiment will, the researchers said, an interesting test of Einstein's equivalence principle, which states that gravity accelerates all objects equally, irrespective of their own mass.

    The principle has been investigated in space before, as can be observed in the famous feather and hammer experiment conducted by Apollo 15 Commander David Scott on the Moon. The equivalence principle is one of the cornerstones of general relativity, and relativity tends to break down in the quantum realm, so the planned experiments are set to be very interesting indeed.

    And it's only going to get more interesting in the future. Sounding rockets go up and come down in suborbital flights, but there are plans to perform even more Bose-Einstein condensate experiments in Earth orbit.

    "Undertaking this kind of experiment would be a future objective on satellites or the International Space Station ISS, possibly within BECCAL, the Bose Einstein Condensate and Cold Atom Laboratory, which is currently in the planning phase," said physicist André Wenzlawski of Johannes Gutenberg University Mainz in Germany.

    "In this case, the achievable accuracy would not be constrained by the limited free-fall time aboard a rocket."

    In just a few short years, we could be using atom interferometry for applications such as quantum tests of general relativity, detection of gravitational waves, and even the search for dark matter and dark energy.

    We can't wait to see what happens next.

    The team's research has been published in Nature Communications.
    For The First Time, Scientists Have Performed Atom Interferometry in Space. To make some of the most precise measurements we can of the world around us, scientists tend to go small - right down to the atomic scale, using a technique called atom interferometry. Now, for the first time, scientists have performed this kind of measurement in space, using a sounding rocket specially designed to carry science payloads into low-Earth space. It's a significant step towards being able to perform matter-wave interferometry in space, for science applications that range from fundamental physics to navigation. "We have established the technological basis for atom interferometry on board of a sounding rocket and demonstrated that such experiments are not only possible on Earth, but also in space," said physicist Patrick Windpassinger of Johannes Gutenberg University Mainz in Germany. Interferometry is a relatively simple in concept. You take two identical waves, separate them, recombine them, and use the small difference between - called a phase shift - to measure the force that caused that distance. This is called an interference pattern. A famous example is LIGO's light interferometer that measures gravitational waves: A beam of light is split down two tunnels miles long, bounced off mirrors and recombined. The resulting interference pattern can be used to detect the gravitational waves caused by colliding black holes millions of light-years away. Atom interferometry, harnessing the wave-like behavior of atoms, is a little trickier to achieve, but has the advantage of a much smaller apparatus. It would be very useful in space, where it could be used to measure things like gravity to a high level of precision; so, a team of German researchers has been working for years to try to make it happen. The first step is to create a state of matter called a Bose-Einstein condensate. These are formed from atoms cooled to just a fraction above absolute zero (but not reaching absolute zero, at which point atoms stop moving). This causes them to sink to their lowest-energy state, moving extremely slowly, and overlapping in quantum superposition - producing a high density cloud of atoms that acts like one 'super atom' or matter wave. This is an ideal starting point for interferometry, because the atoms are all behaving identically, and the team achieved the creation of a Bose-Einstein condensate in space for the first time using their sounding rocket in 2017, with a gas of rubidium atoms. "For us, this ultracold ensemble represented a very promising starting point for atom interferometry," Windpassinger said. For the next stage of their research, they had to separate and recombine the superimposed atoms. Once again, the researchers created their rubidium Bose-Einstein condensate, but this time they used lasers to irradiate the gas, causing the atoms to separate, then come back together in superposition. interference Interference patterns observed in the Bose-Einstein condensate. (Lachmann et al., Nat. Commun., 2021) The resulting interference pattern showed a clear influence from the microgravity environment of the sounding rocket, suggesting that with a bit of refinement, the technique could be used to measure this environment to high precision. The next step of the research, planned for 2022 and 2023, is to try the test again using separate Bose-Einstein condensates of rubidium and potassium to observe their acceleration under free fall. Since rubidium and potassium atoms have different masses, this experiment will, the researchers said, an interesting test of Einstein's equivalence principle, which states that gravity accelerates all objects equally, irrespective of their own mass. The principle has been investigated in space before, as can be observed in the famous feather and hammer experiment conducted by Apollo 15 Commander David Scott on the Moon. The equivalence principle is one of the cornerstones of general relativity, and relativity tends to break down in the quantum realm, so the planned experiments are set to be very interesting indeed. And it's only going to get more interesting in the future. Sounding rockets go up and come down in suborbital flights, but there are plans to perform even more Bose-Einstein condensate experiments in Earth orbit. "Undertaking this kind of experiment would be a future objective on satellites or the International Space Station ISS, possibly within BECCAL, the Bose Einstein Condensate and Cold Atom Laboratory, which is currently in the planning phase," said physicist André Wenzlawski of Johannes Gutenberg University Mainz in Germany. "In this case, the achievable accuracy would not be constrained by the limited free-fall time aboard a rocket." In just a few short years, we could be using atom interferometry for applications such as quantum tests of general relativity, detection of gravitational waves, and even the search for dark matter and dark energy. We can't wait to see what happens next. The team's research has been published in Nature Communications.
    WWW.SCIENCEALERT.COM
    For The First Time, Scientists Have Performed Atom Interferometry in Space
    To make some of the most precise measurements we can of the world around us, scientists tend to go small - right down to the atomic scale, using a technique called atom interferometry.
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