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[PMID]:29370273
[Au] Autor:Sswat M; Stiasny MH; Jutfelt F; Riebesell U; Clemmesen C
[Ad] Endereço:GEOMAR Helmholtz Centre for Ocean Research Kiel, Kiel, Germany.
[Ti] Título:Growth performance and survival of larval Atlantic herring, under the combined effects of elevated temperatures and CO2.
[So] Source:PLoS One;13(1):e0191947, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:In the coming decades, environmental change like warming and acidification will affect life in the ocean. While data on single stressor effects on fish are accumulating rapidly, we still know relatively little about interactive effects of multiple drivers. Of particular concern in this context are the early life stages of fish, for which direct effects of increased CO2 on growth and development have been observed. Whether these effects are further modified by elevated temperature was investigated here for the larvae of Atlantic herring (Clupea harengus), a commercially important fish species. Over a period of 32 days, larval survival, growth in size and weight, and instantaneous growth rate were assessed in a crossed experimental design of two temperatures (10°C and 12°C) with two CO2 levels (400 µatm and 900 µatm CO2) at food levels mimicking natural levels using natural prey. Elevated temperature alone led to increased swimming activity, as well as decreased survival and instantaneous growth rate (Gi). The comparatively high sensitivity to elevated temperature in this study may have been influenced by low food levels offered to the larvae. Larval size, Gi and swimming activity were not affected by CO2, indicating tolerance of this species to projected "end of the century" CO2 levels. A synergistic effect of elevated temperature and CO2 was found for larval weight, where no effect of elevated CO2 concentrations was detected in the 12°C treatment, but a negative CO2 effect was found in the 10°C treatment. Contrasting CO2 effects were found for survival between the two temperatures. Under ambient CO2 conditions survival was increased at 12°C compared to 10°C. In general, CO2 effects were minor and considered negligible compared to the effect of temperature under these mimicked natural food conditions. These findings emphasize the need to include biotic factors such as energy supply via prey availability in future studies on interactive effects of multiple stressors.
[Mh] Termos MeSH primário: Dióxido de Carbono/metabolismo
Peixes/crescimento & desenvolvimento
Larva/crescimento & desenvolvimento
Temperatura Ambiente
[Mh] Termos MeSH secundário: Animais
Mudança Climática
Natação
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
142M471B3J (Carbon Dioxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180126
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191947


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[PMID]:29214783
[Au] Autor:Lee SM; Namgung R; Eun HS; Lee SM; Park MS; Park KI
[Ad] Endereço:Department of Pediatrics, Yonsei University College of Medicine, Seoul, Korea.
[Ti] Título:Effective Tidal Volume for Normocapnia in Very-Low-Birth-Weight Infants Using High-Frequency Oscillatory Ventilation.
[So] Source:Yonsei Med J;59(1):101-106, 2018 Jan.
[Is] ISSN:1976-2437
[Cp] País de publicação:Korea (South)
[La] Idioma:eng
[Ab] Resumo:PURPOSE: Removal of CO2 is much efficient during high-frequency oscillatory ventilation (HFOV) for preterm infants. However, an optimal carbon dioxide diffusion coefficient (DCO2) and tidal volume (VT) have not yet been established due to much individual variance. This study aimed to analyze DCO2 values, VT, and minute volume in very-low-birth-weight (VLBW) infants using HFOV and correlates with plasma CO2 (pCO2). MATERIALS AND METHODS: Daily respiratory mechanics and ventilator settings from twenty VLBW infants and their two hundred seventeen results of blood gas analysis were collected. Patients were treated with the Dräger Babylog VN500 ventilator (Drägerwerk Ag & Co.) in HFOV mode. The normocapnia was indicated as pCO2 ranging from 45 mm Hg to 55 mm Hg. RESULTS: The measured VT was 1.7 mL/kg, minute volume was 0.7 mL/kg, and DCO2 was 43.5 mL²/s. Mean results of the blood gas test were as follows: pH, 7.31; pCO2, 52.6 mm Hg; and SpO2, 90.5%. In normocapnic state, the mean VT was significantly higher than in hypercapnic state (2.1±0.5 mL/kg vs. 1.6±0.3 mL/kg), and the mean DCO2 showed significant difference (68.4±32.7 mL²/s vs. 32.4±15.7 mL²/s). The DCO2 was significantly correlated with the pCO2 (p=0.024). In the receiver operating curve analysis, the estimated optimal cut-off point to predict the remaining normocapnic status was a VT of 1.75 mL/kg (sensitivity 73%, specificity 80%). CONCLUSION: In VLBW infants treated with HFOV, VT of 1.75 mL/kg is recommended for maintaining proper ventilation.
[Mh] Termos MeSH primário: Ventilação de Alta Frequência
Recém-Nascido de muito Baixo Peso/fisiologia
[Mh] Termos MeSH secundário: Gasometria
Dióxido de Carbono/análise
Feminino
Seres Humanos
Hipercapnia/fisiopatologia
Incidência
Lactente
Recém-Nascido
Masculino
Curva ROC
Volume de Ventilação Pulmonar
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
142M471B3J (Carbon Dioxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180309
[Lr] Data última revisão:
180309
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:171208
[St] Status:MEDLINE
[do] DOI:10.3349/ymj.2018.59.1.101


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[PMID]:29397598
[Au] Autor:Yu C; Liu DW; Wang XT; He HW; Pan P; Xing ZQ
[Ad] Endereço:Department of Critical Care Medicine, Peking Union Medical College Hospital, Peking Union Medical College, Chinese Academy of Medical Sciences, Beijing 100730, China.
[Ti] Título:[The clinical significance of microcirculation and oxygen metabolism evaluation in acute kidney injury assessment in patients with septic shock after resuscitation].
[So] Source:Zhonghua Nei Ke Za Zhi;57(2):123-128, 2018 Feb 01.
[Is] ISSN:0578-1426
[Cp] País de publicação:China
[La] Idioma:chi
[Ab] Resumo:To evaluate the value of microcirculation and oxygen metabolism evaluation (MicrOME) in acute kidney injury(AKI) evaluation in patients with septic shock after resuscitation. Consecutive patients with septic shock after resuscitation and mechanical ventilation were enrolled from October 2016 to February 2017 in ICU at Peking Union Medical College Hospital.Patients were divided into 3 groups based on 10 min transcutaneous oxygen challenge test transcutaneous partial pressure of oxygen(PtcO(2))and venoarterial pressure of carbon dioxide difference (Pv-aCO(2)) /arteriovenous O(2) content difference (Ca-vO(2)) by blood gas analysis, i.e. group A [ΔPtcO(2)>66 mmHg(1 mmHg=0.133 kPa) and Pv-aCO(2)/Ca-vO(2)≤1.23], group B (ΔPtcO(2)≤66 mmHg), group C (ΔPtcO(2)>66 mmHg and Pv-aCO(2)/Ca-vO(2)>1.23). Heart rate,mean arterial pressure,central venous pressure,noradrenaline dose,lactate,Pv-aCO(2),Ca-vO(2), lactate clearance, central venous oxygen saturation(ScvO(2)) and liquid equilibrium were assessed after resuscitation.AKI staging based on Kidney Disease Global Improving Outcomes (KDIGO) clinical practice guideline was analyzed. The predictive value of lactate, ScvO(2), Pv-aCO(2)/Ca-vO(2) to progression of AKI after resuscitation was determined using receiver operating characteristic(ROC)curve analysis. A total of 49 septic shock patients were enrolled including 30 males and 19 females with mean age of (61.10±17.10)years old.There were 19 patients in group A,21 patients in group B, and 9 patients in group C. Acute physiology and chronic health evaluation â…¡ score was 20.92±7.19 and sequential organ failure assessment score 12.02±3.28. There were 4 patients with AKI and 1 progressed in group A, 11 patients with AKI and 2 progressed in group B, 6 patients with AKI and 4 progressed in group C. The cutoff value of Pv-aCO(2)/Ca-vO(2) was equal or more than 2.20 for predicting progression of AKI, resulting in a sensitivity of 85.7% and a specificity of 73.8%. MicrOME is a significant parameter to predict the progression of AKI in patients with septic shock after resuscitation. Pv-aCO(2)/Ca-vO(2) is also a good predictive factor.
[Mh] Termos MeSH primário: Lesão Renal Aguda/complicações
Pressão Venosa Central
Microcirculação
Oxigênio/metabolismo
Choque Séptico/complicações
[Mh] Termos MeSH secundário: Lesão Renal Aguda/sangue
Adulto
Idoso
Dióxido de Carbono
Feminino
Frequência Cardíaca
Seres Humanos
Ácido Láctico
Masculino
Meia-Idade
Norepinefrina
Troca Gasosa Pulmonar
Curva ROC
Respiração Artificial
Ressuscitação
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
142M471B3J (Carbon Dioxide); 33X04XA5AT (Lactic Acid); S88TT14065 (Oxygen); X4W3ENH1CV (Norepinephrine)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180306
[Lr] Data última revisão:
180306
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180206
[St] Status:MEDLINE
[do] DOI:10.3760/cma.j.issn.0578-1426.2018.02.008


  4 / 77014 MEDLINE  
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[PMID]:29343713
[Au] Autor:Hare VJ; Loftus E; Jeffrey A; Ramsey CB
[Ad] Endereço:Research Laboratory for Archaeology and the History of Art, School of Archaeology, University of Oxford, 1 South Parks Road, Oxford, OX1 3TG, UK. vincent.john.hare@gmail.com.
[Ti] Título:Atmospheric CO effect on stable carbon isotope composition of terrestrial fossil archives.
[So] Source:Nat Commun;9(1):252, 2018 01 17.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The C/ C ratio of C plant matter is thought to be controlled by the isotopic composition of atmospheric CO and stomatal response to environmental conditions, particularly mean annual precipitation (MAP). The effect of CO concentration on C/ C ratios is currently debated, yet crucial to reconstructing ancient environments and quantifying the carbon cycle. Here we compare high-resolution ice core measurements of atmospheric CO with fossil plant and faunal isotope records. We show the effect of pCO during the last deglaciation is stronger for gymnosperms (-1.4 ± 1.2‰) than angiosperms/fauna (-0.5 ± 1.5‰), while the contributions from changing MAP are -0.3 ± 0.6‰ and -0.4 ± 0.4‰, respectively. Previous studies have assumed that plant C/ C ratios are mostly determined by MAP, an assumption which is sometimes incorrect in geological time. Atmospheric effects must be taken into account when interpreting terrestrial stable carbon isotopes, with important implications for past environments and climates, and understanding plant responses to climate change.
[Mh] Termos MeSH primário: Atmosfera/química
Dióxido de Carbono/química
Isótopos de Carbono/análise
Clima
Fósseis
Plantas/metabolismo
[Mh] Termos MeSH secundário: Ciclo do Carbono
Isótopos de Carbono/química
Mudança Climática
Fotossíntese
Chuvas
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Carbon Isotopes); 142M471B3J (Carbon Dioxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180119
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02691-x


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[PMID]:29311545
[Au] Autor:Chrachri A; Hopkinson BM; Flynn K; Brownlee C; Wheeler GL
[Ad] Endereço:Marine Biological Association, Plymouth, PL1 2PB, UK.
[Ti] Título:Dynamic changes in carbonate chemistry in the microenvironment around single marine phytoplankton cells.
[So] Source:Nat Commun;9(1):74, 2018 01 08.
[Is] ISSN:2041-1723
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Photosynthesis by marine diatoms plays a major role in the global carbon cycle, although the precise mechanisms of dissolved inorganic carbon (DIC) uptake remain unclear. A lack of direct measurements of carbonate chemistry at the cell surface has led to uncertainty over the underlying membrane transport processes and the role of external carbonic anhydrase (eCA). Here we identify rapid and substantial photosynthesis-driven increases in pH and [CO ] primarily due to the activity of eCA at the cell surface of the large diatom Odontella sinensis using direct simultaneous microelectrode measurements of pH and CO along with modelling of cell surface inorganic carbonate chemistry. Our results show that eCA acts to maintain cell surface CO concentrations, making a major contribution to DIC supply in O. sinensis. Carbonate chemistry at the cell surface is therefore highly dynamic and strongly dependent on cell size, morphology and the carbonate chemistry of the bulk seawater.
[Mh] Termos MeSH primário: Carbonatos/metabolismo
Microambiente Celular
Diatomáceas/metabolismo
Fitoplâncton/metabolismo
[Mh] Termos MeSH secundário: Transporte Biológico
Carbono/química
Carbono/metabolismo
Dióxido de Carbono/química
Dióxido de Carbono/metabolismo
Carbonatos/química
Anidrases Carbônicas/metabolismo
Diatomáceas/citologia
Concentração de Íons de Hidrogênio
Modelos Biológicos
Fotossíntese
Fitoplâncton/citologia
Água do Mar/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Carbonates); 142M471B3J (Carbon Dioxide); 7440-44-0 (Carbon); EC 4.2.1.1 (Carbonic Anhydrases)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180110
[St] Status:MEDLINE
[do] DOI:10.1038/s41467-017-02426-y


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[PMID]:28470848
[Au] Autor:Camprubi E; Jordan SF; Vasiliadou R; Lane N
[Ad] Endereço:Department of Genetics, Evolution and Environment, University College London, London, UK.
[Ti] Título:Iron catalysis at the origin of life.
[So] Source:IUBMB Life;69(6):373-381, 2017 06.
[Is] ISSN:1521-6551
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Iron-sulphur proteins are ancient and drive fundamental processes in cells, notably electron transfer and CO fixation. Iron-sulphur minerals with equivalent structures could have played a key role in the origin of life. However, the 'iron-sulphur world' hypothesis has had a mixed reception, with questions raised especially about the feasibility of a pyrites-pulled reverse Krebs cycle. Phylogenetics suggests that the earliest cells drove carbon and energy metabolism via the acetyl CoA pathway, which is also replete in Fe(Ni)S proteins. Deep differences between bacteria and archaea in this pathway obscure the ancestral state. These differences make sense if early cells depended on natural proton gradients in alkaline hydrothermal vents. If so, the acetyl CoA pathway diverged with the origins of active ion pumping, and ancestral CO fixation might have been equivalent to methanogens, which depend on a membrane-bound NiFe hydrogenase, energy converting hydrogenase. This uses the proton-motive force to reduce ferredoxin, thence CO . The mechanism suggests that pH could modulate reduction potential at the active site of the enzyme, facilitating the difficult reduction of CO by H . This mechanism could be generalised under abiotic conditions so that steep pH differences across semi-conducting Fe(Ni)S barriers drives not just the first steps of CO fixation to C1 and C2 organics such as CO, CH SH and CH COSH, but a series of similar carbonylation and hydrogenation reactions to form longer chain carboxylic acids such as pyruvate, oxaloacetate and α-ketoglutarate, as in the incomplete reverse Krebs cycle found in methanogens. We suggest that the closure of a complete reverse Krebs cycle, by regenerating acetyl CoA directly, displaced the acetyl CoA pathway from many modern groups. A later reliance on acetyl CoA and ATP eliminated the need for the proton-motive force to drive most steps of the reverse Krebs cycle. © 2017 IUBMB Life, 69(6):373-381, 2017.
[Mh] Termos MeSH primário: Acetilcoenzima A/química
Ferredoxinas/química
Proteínas com Ferro-Enxofre/química
Ferro/química
Origem da Vida
[Mh] Termos MeSH secundário: Acetilcoenzima A/metabolismo
Archaea/química
Archaea/metabolismo
Bactérias/química
Bactérias/metabolismo
Ciclo do Carbono
Dióxido de Carbono/química
Dióxido de Carbono/metabolismo
Catálise
Ciclo do Ácido Cítrico
Ferredoxinas/metabolismo
Concentração de Íons de Hidrogênio
Fontes Hidrotermais
Ferro/metabolismo
Proteínas com Ferro-Enxofre/metabolismo
Ácidos Cetoglutáricos/química
Ácidos Cetoglutáricos/metabolismo
Ácido Oxaloacético/química
Ácido Oxaloacético/metabolismo
Prótons
Ácido Pirúvico/química
Ácido Pirúvico/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Ferredoxins); 0 (Iron-Sulfur Proteins); 0 (Ketoglutaric Acids); 0 (Protons); 142M471B3J (Carbon Dioxide); 2F399MM81J (Oxaloacetic Acid); 72-89-9 (Acetyl Coenzyme A); 8558G7RUTR (Pyruvic Acid); 8ID597Z82X (alpha-ketoglutaric acid); E1UOL152H7 (Iron)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180305
[Lr] Data última revisão:
180305
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170505
[St] Status:MEDLINE
[do] DOI:10.1002/iub.1632


  7 / 77014 MEDLINE  
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[PMID]:29300076
[Au] Autor:Gilbert S; Singh D; Sivakumar MK
[Ad] Endereço:Department of cardiothoracic surgery. Kovai medical center and hospital limited. Post box no. 3209, Avanashi road, Coimbatore - 641014, Tamil Nadu, India.
[Ti] Título:Modified carbodissection: A new technique for harvesting the internal mammary artery.
[So] Source:Multimed Man Cardiothorac Surg;2017, 2017 Oct 29.
[Is] ISSN:1813-9175
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The modified carbodissection technique is a new technique for harvesting the internal mammary artery during coronary artery bypass graft surgery. It is performed using an improvised instrument that consists of an electrocautery device and a carbon dioxide blower/mister. It combines electrocautery dissection and continuous controlled gas blow dissection along with saline irrigation mist. Gas dissection causes vasodilation and maintains the artery in a dilated state during dissection. Saline flow reduces the amount of heat generated at the cautery site and prevents drying and desiccation of the tissues. This technique is safe in terms of reduced thermal injury, and reduced early arterial spasm and myocardial ischemia, and it improves vision during harvest and shortens the duration of the harvesting procedure.
[Mh] Termos MeSH primário: Ponte de Artéria Coronária
Dissecação/métodos
Eletrocirurgia/métodos
Artéria Torácica Interna/cirurgia
Coleta de Tecidos e Órgãos/métodos
[Mh] Termos MeSH secundário: Dióxido de Carbono/uso terapêutico
Gases/uso terapêutico
Seres Humanos
Artéria Torácica Interna/transplante
[Pt] Tipo de publicação:VIDEO-AUDIO MEDIA
[Nm] Nome de substância:
0 (Gases); 142M471B3J (Carbon Dioxide)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180302
[Lr] Data última revisão:
180302
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180105
[St] Status:MEDLINE
[do] DOI:10.1510/mmcts.2017.018


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[PMID]:29478638
[Au] Autor:Jin P; Song J; Wang XC; Jin X
[Ad] Endereço:School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China. Electronic address: pkjin@xauat.edu.cn.
[Ti] Título:Two-dimensional correlation spectroscopic analysis on the interaction between humic acids and aluminum coagulant.
[So] Source:J Environ Sci (China);64:181-189, 2018 Feb.
[Is] ISSN:1001-0742
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:In this study, two-dimensional correlation spectroscopy integrated with synchronous fluorescence and infrared absorption spectroscopy was employed to investigate the interaction between humic acids and aluminum coagulant at slightly acidic and neutral pH. Higher fluorescence quenching was produced for fulvic-like and humic-like fractions at pH5. At pH5, the humic-like fractions originating from the carboxylic acid, carboxyl and polysaccharide compounds were bound to aluminum first, followed by the fulvic-like fractions originating from the carboxyl and polysaccharide compounds. This finding also demonstrated that the activated functional groups of HA were involved in forming the Al-HA complex, which was accompanied by the removal of other groups by co-precipitation. Meanwhile, at pH7, almost no fluorescence quenching occurred, and surface complexation was observed to occur, in which the activated functional groups were absorbed on the amorphous Al(OH) . Two-dimensional FT-IR correlation spectroscopy indicated the sequence of HA structural change during coagulation with aluminum, with IR bands affected in the order of COOH>COO >NH deformation of amide II>aliphatic hydroxyl COH at pH5, and COO >aliphatic hydroxyl COH at pH7. This study provides a promising pathway for analysis and insight into the priority of functional groups in the interaction between organic matters and metal coagulants.
[Mh] Termos MeSH primário: Alumínio/química
Substâncias Húmicas
Modelos Químicos
[Mh] Termos MeSH secundário: Amidas
Dióxido de Carbono
Ácidos Carboxílicos
Fluorescência
Concentração de Íons de Hidrogênio
Radical Hidroxila
Espectrofotometria Infravermelho
Espectroscopia de Infravermelho com Transformada de Fourier
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Amides); 0 (Carboxylic Acids); 0 (Humic Substances); 142M471B3J (Carbon Dioxide); 14485-07-5 (carboxyl radical); 3352-57-6 (Hydroxyl Radical); CPD4NFA903 (Aluminum)
[Em] Mês de entrada:1803
[Cu] Atualização por classe:180301
[Lr] Data última revisão:
180301
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180227
[St] Status:MEDLINE


  9 / 77014 MEDLINE  
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[PMID]:29373605
[Au] Autor:Tobin RL; Kulmatiski A
[Ad] Endereço:Department of Wildland Resources and Ecology Center, Utah State University, Logan, Utah, United States of America.
[Ti] Título:Plant identity and shallow soil moisture are primary drivers of stomatal conductance in the savannas of Kruger National Park.
[So] Source:PLoS One;13(1):e0191396, 2018.
[Is] ISSN:1932-6203
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Our goal was to describe stomatal conductance (gs) and the site-scale environmental parameters that best predict gs in Kruger National Park (KNP), South Africa. Dominant grass and woody species were measured over two growing seasons in each of four study sites that represented the natural factorial combination of mean annual precipitation [wet (750 mm) or dry (450 mm)] and soil type (clay or sand) found in KNP. A machine-learning (random forest) model was used to describe gs as a function of plant type (species or functional group) and site-level environmental parameters (CO2, season, shortwave radiation, soil type, soil moisture, time of day, vapor pressure deficit and wind speed). The model explained 58% of the variance among 6,850 gs measurements. Species, or plant functional group, and shallow (0-20 cm) soil moisture had the greatest effect on gs. Atmospheric drivers and soil type were less important. When parameterized with three years of observed environmental data, the model estimated mean daytime growing season gs as 68 and 157 mmol m-2 sec-1 for grasses and woody plants, respectively. The model produced here could, for example, be used to estimate gs and evapotranspiration in KNP under varying climate conditions. Results from this field-based study highlight the role of species identity and shallow soil moisture as primary drivers of gs in savanna ecosystems of KNP.
[Mh] Termos MeSH primário: Dióxido de Carbono/metabolismo
Folhas de Planta/metabolismo
Plantas/classificação
Plantas/metabolismo
Solo/química
Água/metabolismo
[Mh] Termos MeSH secundário: Atmosfera/química
Aprendizado de Máquina
Modelos Estatísticos
Poaceae/metabolismo
África do Sul
Madeira/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Soil); 059QF0KO0R (Water); 142M471B3J (Carbon Dioxide)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180226
[Lr] Data última revisão:
180226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180127
[St] Status:MEDLINE
[do] DOI:10.1371/journal.pone.0191396


  10 / 77014 MEDLINE  
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[PMID]:29367147
[Au] Autor:Aslam A; Thomas-Hall SR; Manzoor M; Jabeen F; Iqbal M; Uz Zaman Q; Schenk PM; Asif Tahir M
[Ad] Endereço:Department of Environmental Science, University of Lahore, Lahore, Pakistan; Algae Biotechnology Laboratory, School of Agriculture and Food Sciences, University of Queensland, Brisbane, Queensland 4072, Australia. Electronic address: ambreenaslam86@hotmail.com.
[Ti] Título:Mixed microalgae consortia growth under higher concentration of CO from unfiltered coal fired flue gas: Fatty acid profiling and biodiesel production.
[So] Source:J Photochem Photobiol B;179:126-133, 2018 Feb.
[Is] ISSN:1873-2682
[Cp] País de publicação:Switzerland
[La] Idioma:eng
[Ab] Resumo:Biodiesel is produced by transesterification of fatty acid methyl esters (FAME) from oleaginous microalgae feedstock. Biodiesel fuel properties were studied and compared with biodiesel standards. Qualitative analysis of FAME was done while cultivating mixed microalgae consortia under three concentrations of coal fired flue gas (1%, 3.0% and 5.5% CO ). Under 1% CO concentration (flue gas), the FAME content was 280.3 µg/mL, whereas the lipid content was 14.03 µg/mL/D (day). Both FAMEs and lipid contents were low at other CO concentrations (3.0 and 5.5%). However, mixed consortia in the presence of phosphate buffer and flue gas (PB + FG) showed higher saturated fatty acids (SFA) (36.28%) and unsaturated fatty acids (UFA) (63.72%) versus 5.5% CO concentration, which might be responsible for oxidative stability of biodiesel. Subsequently, higher cetane number (52) and low iodine value (136.3 gI /100 g) biodiesel produced from mixed consortia (PB + FG) under 5.5% CO along with 50 mM phosphate buffer were found in accordance with European (EN 14214) standard. Results revealed that phosphate buffer significantly enhanced the biodiesel quality, but reduced the FAME yield. This study intended to develop an integrated approach for significant improvement in biodiesel quality under surplus phosphorus by utilizing waste flue gas (as CO source) using microalgae. The CO sequestration from industrial flue gas not only reduced greenhouse gases, but may also ensure the sustainable and eco-benign production of biodiesel.
[Mh] Termos MeSH primário: Biocombustíveis
Dióxido de Carbono/metabolismo
Ácidos Graxos/análise
Microalgas/metabolismo
[Mh] Termos MeSH secundário: Biomassa
Dióxido de Carbono/química
Cromatografia Gasosa
Carvão Mineral/análise
Ácidos Graxos/metabolismo
Gases/química
Espectrometria de Massas
Microalgas/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biofuels); 0 (Coal); 0 (Fatty Acids); 0 (Gases); 142M471B3J (Carbon Dioxide)
[Em] Mês de entrada:1802
[Cu] Atualização por classe:180223
[Lr] Data última revisão:
180223
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:180126
[St] Status:MEDLINE



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