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Low bandgap polymers from fused dithiophene diester
The present invention involves monomeric compounds having the structure: ##STR1## Substituents W and Z are independently --CN, --NO.sub.2, -aryl, -aryl-V, --COX, SO.sub.2 R, --H, or -alkyl. Substituent X is --OR, or --NR,R where R and R.sup.1 are independently -alkyl or --H. Substituent V is -halide, --NO.sub.2, --CN, --SO.sub.2 R, or --COX. At least one of W and Z is --NO.sub.2, --SO.sub.2 R, --CN, --COX or -aryl-V. In one preferred embodiment substituents W and Z are both --CN. In another preferred embodiment, substituent X is --NO.sub.2 or --CN and substituent Z is --C.sub.6 H.sub.4 NO.sub.2. These monomers are polymerized to form low bandgap polymers.Board of Regents, University of Texas Syste
Indole modifies the central carbon flux in the anaerobic metabolism of Escherichia coli: application to the production of hydrogen and other metabolites.
Indole is a bicyclic signaling molecule with effects on both eukaryotic and prokaryotic cells. The majority of studies of indole action have been performed with bacteria cultured under aerobic conditions and little information is available about its effects under anaerobic conditions. Here the effect of the indole on anaerobic metabolism of Escherichia coli WDHL was studied. Indole in the range 0.5-8mM was added to the culture medium and cell growth, hydrogen and metabolite production were compared to cultures lacking indole. Results showed that while 8mM indole abolished growth completely, 4mM indole had a partial bacteriostatic effect and the maximum optical density of the culture decreased by 44% compared to the control cultures. In addition, 4mM indole had an important effect on anaerobic metabolism. Hydrogen production increased from 650±115 to 1137±343mL H2/L, and hydrogen yield increased from 0.45±0.1 to 0.94±0.34mol H2/mol glucose, compared to the control culture. Carbon flux was also affected and the composition of the final by-products changed. Lactate (41mM) was the main metabolite in the control cultures, whereas ethanol (56.2mM) and acetate (41.2mM) were the main metabolites in the cultures with 2mM indole. We conclude that the supplementation of E. coli cultures with exogenous indole is a simple and novel strategy to improve the production of hydrogen as well as other metabolites such as ethanol used as biofuels.Partial financial support from CONACyT Grant Pro Nal 247498, SENER-Cemie Bio249564, and CONACyT sabbatical fellowship 259644.This is the author accepted manuscript. The final version is available from Elsevier via https://doi.org/10.1016/j.nbt.2016.09.00
Dynamic behaviour of multi-terminal VSC-based HVDC after a converter outage: DC control strategy
The aim of this paper is to evaluate the effect of DC-voltage control strategy on dynamic behaviour of multi-terminal Voltage-Source Converter (VSC)-Based HVDC after a converter outage. In this paper, two dc voltage control strategies are considered: (i) standard voltage margin method (SVMM) and (ii) standard voltage-droop method (SVDM). The impact is evaluated in this paper using time-domain simulations on simple test system using DIgSILENT PowerFactory considering a sudden disconnection of a converter-station. Simulation results demonstrate how important is the dc-voltage control strategy and the location/number of dc-buses involved in the dc-voltage on the dynamic response of the MTDC systems. The voltage margin control is capable to survive a converter outage just if this converter is operating on constant power mode
Structural insights into PYR/PYL/RCAR ABA receptors and PP2Cs
[EN] Abscisic acid (ABA) plays an essential function in plant physiology since it is required for biotic and abiotic stress responses as well as control of plant growth and development. A new family of soluble ABA receptors, named PYR/PYL/RCAR, has emerged as ABA sensors able to inhibit the activity of specific protein phosphatases type-2C (PP2Cs) in an ABA-dependent manner. The structural and functional mechanism by which ABA is perceived by these receptors and consequently leads to inhibition of the PP2Cs has been recently elucidated. The module PYR/PYL/RCAR-ABA-PP2C offers an elegant and unprecedented mechanism to control phosphorylation signaling cascades in a ligand-dependent manner. The knowledge of their three-dimensional structures paves the way to the design of ABA agonists able to modulate the plant stress response. (C) 2010 Elsevier Ireland Ltd. All rights reserved.We are grateful to the European Synchrotron Radiation Facility (ESRF) and the EMBL for access to macromolecular crystallography beam lines. Work in the laboratory of Dr Rodriguez is supported by grant BIO2008-00221 from Ministerio de EducaciĂłn y Ciencia and Fondo Europeo de Desarrollo Regional and Consejo Superior de Investigaciones CientĂficas (fellowships to JS, RA and LR; Juan de la Cierva contract to MGG). Access to the high Throughput Crystallization facility of the Partnership for Structural Biology in Grenoble (PSB) (https://htxlab.embl.fr) was supported by the European
Community – Research InfrastructureAction PCUBE under the FP7 “Capacities” specific program.Santiago Cuéllar, J.; Dupeux, F.; Betz, K.; Antoni-Alandes, R.; González Guzmán, M.; Rodriguez, L.; Márquez, JA.... (2012). Structural insights into PYR/PYL/RCAR ABA receptors and PP2Cs. Plant Science. 182:3-11. https://doi.org/10.1016/j.plantsci.2010.11.014S31118
Early life adiposity and telomere length across the life course: a systematic review and meta-analysis [version 2; referees: 2 approved]
Background: The relationship between adiposity at birth and in childhood, and telomere length is yet to be determined. We aimed to systematically review and meta-analyse the results of studies assessing associations between neonatal and later childhood adiposity, and telomere length. Methods: We searched Medline, EMBASE and PubMed for studies reporting associations between adiposity measured in the neonatal period or later childhood/adolescence, and leucocyte telomere length, measured at any age via quantitative polymerase chain reaction, or terminal restriction fragment analysis, either cross-sectionally, or longitudinally. Papers published before April 2017 were included. Results: Out of 230 abstracts assessed, 23 papers (32 estimates) were retained, from which 19 estimates were meta-analysed (15 cross-sectional, four longitudinal). Of the 15 cross-sectional estimates, seven reported on neonates: four used binary exposures of small-for-gestational-age vs. appropriate-for-gestational age (or appropriate- and large-for-gestational age), and three studied birth weight continuously. Eight estimates reported on later childhood or adolescent measures; five estimates were from studies of binary exposures (overweight/obese vs. non-obese children), and three studies used continuous measures of body mass index. All four longitudinal estimates were of neonatal adiposity, with two estimates for small-for-gestational-age vs. appropriate-for-gestational age neonates, and two estimates of birth weight studied continuously, in relation to adult telomere (49-61 years). There was no strong evidence of an association between neonatal or later childhood/adolescent adiposity, and telomere length. However, between study heterogeneity was high, and there were few combinable studies. Conclusions: Our systematic review and meta-analysis found no strong evidence of an association between neonatal or later childhood or adolescent adiposity and telomere length
Pilot study of the characteristics of acute stroke events in patients discharged from the Carolina University Hospital, Puerto Rico in 2007
BACKGROUND: Stroke is the third leading cause of death in Puerto Rico. We examined the pre-hospital phase, management and case-fatality-rates (CFR) of patients discharged with acute stroke from the Carolina University of Puerto Rico Hospital during 2007.
METHODS: Trained personnel collected information on demographics, delay-time, mode-of-transportation, management, and mortality from all medical records. STATAa was utilized to conduct univariate comparison of demographics, mode-of-transportation, therapeutics and diagnostic characteristics. Logistic regression analysis assessed cohort effect and controlled for confounders.
RESULTS: The average age was 69.1 years, and 53% were males. The average delay between onset of symptoms suggestive of stroke and arrival at the emergency department was 4.5 hours. Only 62% of patients utilized Emergency Medical Services (EMS). Intravenous thrombolysis was not administered. Stroke mortality increased with age. Ischemic vs. hemorrhagic CFR was significantly higher (63.9% vs. 36.10%; p = 0.034).
CONCLUSIONS: These findings highlight the potential benefit of evidence-based therapeutics and EMS use among stroke patients
Unique Features of HLA-Mediated HIV Evolution in a Mexican Cohort: A Comparative Study
Background:
Mounting evidence indicates that HLA-mediated HIV evolution follows highlystereotypic pathways that result in HLA-associated footprints in HIV at the population level.However, it is not known whether characteristic HLA frequency distributions in differentpopulations have resulted in additional unique footprints.
Methods:
The phylogenetic dependency network model was applied to assess HLA-mediatedevolution in datasets of HIV pol sequences from free plasma viruses and peripheral bloodmononuclear cell (PBMC)-integrated proviruses in an immunogenetically unique cohort of Mexicanindividuals. Our data were compared with data from the IHAC cohort, a large multi-center cohortof individuals from Canada, Australia and the USA.Results: Forty three different HLA-HIV codon associations representing 30 HLA-HIV codon pairswere observed in the Mexican cohort (q < 0.2). Strikingly, 23 (53%) of these associations differedfrom those observed in the well-powered IHAC cohort, strongly suggesting the existence of uniquecharacteristics in HLA-mediated HIV evolution in the Mexican cohort. Furthermore, 17 of the 23novel associations involved HLA alleles whose frequencies were not significantly different fromthose in IHAC, suggesting that their detection was not due to increased statistical power but todifferences in patterns of epitope targeting. Interestingly, the consensus differed in four positionsbetween the two cohorts and three of these positions could be explained by HLA-associated selection. Additionally, different HLA-HIV codon associations were seen when comparing HLAmediatedselection in plasma viruses and PBMC archived proviruses at the population level, with asignificantly lower number of associations in the proviral dataset.
Conclusion:
Our data support universal HLA-mediated HIV evolution at the population level,resulting in detectable HLA-associated footprints in the circulating virus. However, it also stronglysuggests that unique genetic backgrounds in different HIV-infected populations may influence HIVevolution in a particular direction as particular HLA-HIV codon associations are determined byspecific HLA frequency distributions. Our analysis also suggests a dynamic HLA-associatedevolution in HIV with fewer HLA-HIV codon associations observed in the proviral compartment,which is likely enriched in early archived HIV sequences, compared to the plasma viruscompartment. These results highlight the importance of comparative HIV evolutionary studies inimmunologically different populations worldwide
Association of copy number variation across the genome with neuropsychiatric traits in the general population
Copy number variants (CNVs) are associated with psychiatric conditions in clinical populations. The relationship between rare CNV burden and neuropsychiatric traits in young, general populations is underexplored. 6807 children from the Avon Longitudinal Study of Parents and Children (ALSPAC) were studied. CNVs were inferred from SNP-array data using PennCNV. After excluding children with known candidate CNVs for schizophrenia, rare (<1%) CNV burden (total number of genes affected by CNVs, total length of CNVs, and largest CNV carried) was analysed in relation to: psychotic experiences (PEs) and anxiety/depression in adolescence; autism spectrum disorder (ASD) and attention-deficit hyperactivity disorder (ADHD), ASD and ADHD traits, and cognitive measures during childhood. Outcomes were also assessed in relation to known schizophrenia CNVs. The number of genes affected by rare CNVs was associated with a continuous measure of ASD: the standardised mean difference [SMD] per gene affected was increased by 0.018 [95%CI 0.011,0.025], p=3e-07 for duplications and by 0.021 [95%CI 0.010, 0.032], p=1e-04 for deletions. In line with published results on educational attainment in ALSPAC, IQ was associated with CNV burden: the SMD per gene affected was -0.017 [95%CI -0.025,-0.008] p=1e-04 for duplications and -0.023 [95%CI -0.037, -0.009], p=0.002 for deletions. Associations were also observed for measures of coherence, attention, memory, and social cognition. Schizophrenia-associated deletions were associated with IQ (SMD: -0.617 [95%CI -0.936,-0.298], p=2e-04), but not with PEs or other traits. We found that rare CNV burden and known schizophrenia candidate CNVs are associated with neuropsychiatric phenotypes in a non-clinically ascertained sample of young people
Chemostat culture systems support diverse bacteriophage communities from human feces
BACKGROUND: Most human microbiota studies focus on bacteria inhabiting body surfaces, but these surfaces also are home to large populations of viruses. Many are bacteriophages, and their role in driving bacterial diversity is difficult to decipher without the use of in vitro ecosystems that can reproduce human microbial communities. RESULTS: We used chemostat culture systems known to harbor diverse fecal bacteria to decipher whether these cultures also are home to phage communities. We found that there are vast viral communities inhabiting these ecosystems, with estimated concentrations similar to those found in human feces. The viral communities are composed entirely of bacteriophages and likely contain both temperate and lytic phages based on their similarities to other known phages. We examined the cultured phage communities at five separate time points over 24Â days and found that they were highly individual-specific, suggesting that much of the subject-specificity found in human viromes also is captured by this culture-based system. A high proportion of the community membership is conserved over time, but the cultured communities maintain more similarity with other intra-subject cultures than they do to human feces. In four of the five subjects, estimated viral diversity between fecal and cultured communities was highly similar. CONCLUSIONS: Because the diversity of phages in these cultured fecal communities have similarities to those found in humans, we believe these communities can serve as valuable ecosystems to help uncover the role of phages in human microbial communities
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