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101.
102.
Laura Remacha David Pirman Christopher E. Mahoney Javier Coloma Bruna Calsina Maria Currás-Freixes Rocío Letón Rafael Torres-Pérez Susan Richter Guillermo Pita Belén Herráez Giovanni Cianchetta Emiliano Honrado Lorena Maestre Miguel Urioste Javier Aller Óscar García-Uriarte María Ángeles Gálvez Alberto Cascón 《American journal of human genetics》2019,104(5):1008-1010
103.
Emma Bell Angela Sherry Giovanni Pilloni Ana Suárez-Suárez Margaret A. Cramm Guillermo Cueto Ian M. Head Casey R. J. Hubert 《Environmental microbiology》2020,22(1):456-465
Thermophilic endospores are widespread in cold marine sediments where the temperature is too low to support growth and activity of thermophiles in situ. These endospores are likely expelled from warm subsurface environments and subsequently dispersed by ocean currents. The endospore upper temperature limit for survival is 140°C, which can be tolerated in repeated short exposures, potentially enabling transit through hot crustal fluids. Longer-term thermal tolerance of endospores, and how long they could persist in an environment hotter than their maximum growth temperature, is less understood. To test whether thermophilic endospores can survive prolonged exposure to high temperatures, sediments were incubated at 80–90°C for 6, 12 or 463 days. Sediments were then cooled by 10–40°C, mimicking the cooling in subsurface oil reservoirs subjected to seawater injection. Cooling the sediments induced sulfate reduction, coinciding with an enrichment of endospore-forming Clostridia. Different Desulfofundulus, Desulfohalotomaculum, Desulfallas, Desulfotomaculum and Desulfofarcimen demonstrated different thermal tolerances, with some Desulfofundulus strains surviving for >1 year at 80°C. In an oil reservoir context, heat-resistant endospore-forming sulfate-reducing bacteria have a survival advantage if they are introduced to, or are resident in, an oil reservoir normally too hot for germination and growth, explaining observations of reservoir souring following cold seawater injection. 相似文献
104.
Jianyu Yuan Michael J. Ford Yalong Xu Yannan Zhang Guillermo C. Bazan Wanli Ma 《Liver Transplantation》2018,8(14)
All‐polymer solar cells (all‐PSCs) are attractive as alternatives to fabricate thermally and mechanically stable solar cells, especially with recent improvements in their power conversion efficiency (PCE). In this work, efficient all‐PSCs with near‐infrared response (up to 850 nm) are developed using newly designed regioregular polymer donors with relatively narrow optical gap. These all‐PSCs systems achieve PCEs up to 6.0% after incorporating fluorine into the polymer backbone. More importantly, these polymers exhibit absorbance that is complementary to previously reported wide bandgap polymer donors. Thus, the superior properties of the newly designed polymers afford opportunities to fabricate the first spectrally matched all‐polymer tandem solar cells with high performance. A PCE of 8.3% is then demonstrated which is the highest efficiency so far for all‐polymer tandem solar cells. The design of narrow bandgap polymers provides new directions to enhance the PCE of emerging single‐junction and tandem all polymer solar cells. 相似文献
105.
106.
Matilde Valencia‐Flores Arturo Orea Violeta A. Castao Montserrat Resendiz María Rosales Vernica Rebollar Victoria Santiago Jos Gallegos Rosa M. Campos Jorge Gonzlez Jorge Oseguera Guillermo García‐Ramos Donald L. Bliwise 《Obesity (Silver Spring, Md.)》2000,8(3):262-269
Objective: To determine the prevalence of sleep apnea in morbidly obese patients and its relationship with cardiac arrhythmias. Research Methods and Procedures: Fifty‐two consecutive morbidly obese (body mass index ≥ 40 kg/m2) outpatients from the Obesity Clinic of the National Institute of Nutrition Salvador Zubirán underwent two nights of polysomnography with standard laboratory techniques. Electrocardiographic polysomnography signals (Lead II) were evaluated by two experienced cardiologists, and sleep complaints were measured with a standard sleep questionnaire (Sleep Disorders Questionnaire). In order to make comparisons between groups with different severities of sleep‐disordered breathing, we classified the patients in four groups using the apnea‐hypopnea index (AHI): Group 1, AHI 5 < 15 (n = 10); Group 2, AHI 15 < 30 (n = 10); Group 3, AHI 30 < 65 (n = 14); Group 4, AHI ≥ 65 (n = 17). Results: A wide range of sleep‐disordered breathing, ranging from AHI of 2.5 to 128.9 was found. Ninety‐eight percent of the sample (n = 51) had an AHI ≥ 5 (mean = 51 ± 37), and 33% had severe sleep apnea with AHI ≥ 65 with a mean nocturnal desaturation time of <65% over 135 minutes. Electrocardiographic abnormalities were present in 31% of the patients. Cardiac rhythm alterations showed an association with the level of sleep‐disordered breathing and oxygen desaturation. Discussion: We conclude that there is a high prevalence of sleep apnea in morbidly obese patients and that the risk for cardiac arrhythmias increases in this population in the presence of a severe sleep apnea (AHI ≥ 65) with severe oxygen desaturation (Sao 2 ≤ 65%). 相似文献
107.
Synergistic Impact of Solvent and Polymer Additives on the Film Formation of Small Molecule Blend Films for Bulk Heterojunction Solar Cells 下载免费PDF全文
Caitlin McDowell Maged Abdelsamie Kui Zhao Detlef‐M. Smilgies Guillermo C. Bazan Aram Amassian 《Liver Transplantation》2015,5(18)
The addition of polystyrene (PS), a typical insulator, is empirically shown to increase the power conversion efficiencies (PCEs) of a solution‐deposited bulk heterojunction (BHJ) molecular blend film used in solar cell fabrication: p‐DTS(FBTTh2)2/PC71BM. The performance is further improved by small quantities of diiodooctane (DIO), an established solvent additive. In this study, how the addition of PS and DIO affects the film formation of this bulk heterojunction blend film are probed via in situ monitoring of absorbance, thickness, and crystallinity. PS and DIO additives are shown to promote donor crystallite formation on different time scales and through different mechanisms. PS‐containing films retain chlorobenzene solvent, extending evaporation time and promoting phase separation earlier in the casting process. This extended time is insufficient to attain the morphology for optimal PCE results before the film sets. Here is where the presence of DIO comes into play: its low vapor pressure further extends the time scale of film evolution and allows for crystalline rearrangement of the donor phase long after casting, ultimately leading to the best BHJ organization. 相似文献
108.
Cristián A. Quintero Claudio G. Giraudo Marcos Villarreal Guillermo Montich Hugo J. F. Maccioni 《The Journal of biological chemistry》2010,285(39):30340-30346
Glycolipid glycosyltransferases (GGT) are transported from the endoplasmic reticulum (ER) to the Golgi, their site of residence, via COPII vesicles. An interaction of a (R/K)X(R/K) motif at their cytoplasmic tail (CT) with Sar1 is critical for the selective concentration in the transport vesicles. In this work using computational docking, we identify three putative binding pockets in Sar1 (sites A, B, and C) involved in the interaction with the (R/K)X(R/K) motif. Sar1 mutants with alanine replacement of amino acids in site A were tested in vitro and in cells. In vitro, mutant versions showed a reduced ability to bind immobilized peptides with the CT sequence of GalT2. In cells, Sar1 mutants (Sar1D198A) specifically affect the exiting of GGT from the ER, resulting in an ER/Golgi concentration ratio favoring the ER. Neither the typical Golgi localization of GM130 nor the exiting and transport of the G protein of the vesicular stomatitis virus were affected. The protein kinase inhibitor H89 produced accumulation of Sec23, Sar1, and GalT2 at the ER exit sites; Sar1D189A also accumulated at these sites, but in this case GalT2 remained disperse along ER membranes. The results indicate that amino acids in site A of Sar1 are involved in the interaction with the CT of GGT for concentration at ER exiting sites. 相似文献
109.
Scholz FG Bucci SJ Goldstein G Meinzer FC Franco AC Miralles-Wilhelm F 《Plant, cell & environment》2007,30(2):236-248
Biophysical characteristics of sapwood and outer parenchyma water storage compartments were studied in stems of eight dominant Brazilian Cerrado tree species to assess the impact of differences in tissue capacitance on whole-plant water relations. The rate of decline in tissue water potential with relative water content (RWC) was greater in the outer parenchyma than in the sapwood for most of the species, resulting in tissue-and species-specific differences in capacitance. Sapwood capacitance on a tissue volume basis ranged from 40 to 160 kg m-3 MPa-1, whereas outer parenchyma capacitance ranged from 25 to only 60 kg m-3 MPa-1. In addition, osmotic potentials at full turgor and at the turgor loss point were more negative for the outer parenchyma compared with the sapwood, and the maximum bulk elastic modulus was higher for the outer parenchyma than for the sapwood. Sapwood capacitance decreased linearly with increasing sapwood density across species, but there was no significant correlation between outer parenchyma capacitance and tissue density. Midday leaf water potential, the total hydraulic conductance of the soil/leaf pathway and stomatal conductance to water vapour (gs) all increased with stem volumetric capacitance, or with the relative contribution of stored water to total daily transpiration. However, the difference between the pre-dawn water potential of non-transpiring leaves and the weighted average soil water potential, a measure of the water potential disequilibrium between the plant and soil, increased asymptotically with total stem capacitance across species, implying that overnight recharge of water storage compartments was incomplete in species with greater capacitance. Overall, stem capacitance contributes to homeostasis in the diurnal and seasonal water balance of Cerrado trees. 相似文献
110.
María?F.?MonteroEmail author Manuela?Aristizábal Guillermo?García Reina 《Journal of applied phycology》2011,23(6):1053-1057
Biodiesel from algae is considered an alternative for a third generation of biofuels. However, most microalgae are not lipogenic
during fast growth periods, but high-lipid content occurs at resting stages. Microalgae biomass production for biodiesel needs
continuous high volumetric and aerial yields and large amount of neutral lipid in the biomass. These requirements are similar
to demanding a marathon runner to be obese. We show that by using cell sorting capabilities of flow cytometers, in combination
with the lipid-soluble fluorescent dye Nile Red, we can isolate and select cells with a high and stable lipid content. In
our study, we were able to select the equivalent of a stable “fat marathon runner” through three sorting events obtained from
wild populations of Tetraselmis suecica. 相似文献