1,805 research outputs found
Diluted manganese on the bond-centered site in germanium
The functional properties of Mn-doped Ge depend to large extent on the lattice location of the Mn impurities. Here, we present a lattice location study of implanted diluted Mn by means of electron emission channeling. Surprisingly, in addition to the expected substitutional lattice position, a large fraction of the Mn impurities occupies the bond-centered site. Corroborated by ab initio calculations, the bond-centered Mn is related to Mn-vacancy complexes. These unexpected results call for a reassessment of the theoretical studies on the electrical and magnetic behavior of Mn-doped Ge, hereby including the possible role of Mn-vacancy complexes
That Should Be Left to Doctors, That's What They are There For! - Exploring the Reflexivity and Trust of Young Adults When Seeking Health Information
This paper explores the health information-seeking practices of healthy young adults and how they assess and rank sources of information through a qualitative study. The findings show that participants (a) are strongly committed to searching for information about health and lifestyle, especially via the Internet; (b) healthcare professionals were perceived as the most reliable source of health information and advice; (c) online health information, although frequently accessed and experienced as empowering, is seen as a potentially unreliable source. Findings evidence how becoming better informed about health-related topics plays a pivotal role in individuals’ lives, most notably by using the Internet. Participants were able to reflect about what it means to know about health. The construction of trust regarding health information involved a heuristic process vis-à-vis source reliability and perceived credibility that places doctors as the most trustworthy medium of medical advice and health information. We conclude that participants’ trust toward professionals suggests the preference and need for more personalized care; and it is a response to the ambiguity and uncertainty that permeates the health information landscape, particularly that which is web-based.This article draws on research conducted as part of the project “Evaluating the State of Public Knowledge on Health and Health Information in Portugal” (HMSP/IISE/SAU-ICT/0003/2009), funded by the Portuguese Foundation for Science and Technology (FCT) within the Harvard Medical School-Portugal Program on Translational Research and Health Information. Part of this work has been financed by FEDER funds through the COMPETE 2020—POCI, Portugal 2020, and by Portuguese funds through FCT/Ministério da Ciência, Tecnologia e Inovação—project “Institute for Research and Innovation in Health Sciences” (POCI-01-0145-FEDER-007274). ÁM (SFRH/BPD/88647/2012) and LA (SFRH/BD/78949/2011) are both supported by fellowships from FCT. The authors would like to thank all the participants in this study, the coordinators of the EpiTeen study, and the administrative staff of the Epidemiology department of the Faculty of Medicine of the University of Porto. The authors would also like to thank Liliana Gil and Patrícia Ferreira (Centre for Social Studies, University of Coimbra, Portugal) for their collaboration in part of the interviews, and Rute Verdade for her help in proofreading this text. The authors are also grateful to anonymous reviewers for their helpful comments and suggestions that very much improved the quality of the paper
t(2;11)(q37;q23) in AML
Review on t(2;11)(q37;q23) in AML, with data on clinics, and the genes involved
Brazilian Bidens pilosa Linne´ yields fraction containing quercetin-derived flavonoid with free radical scavenger activity and hepatoprotective effects
Bidens pilosa is a plant used by Amazonian and Asian folks for some hepatopathies. The hydroethanol crude extract and three fractions were assessed for antioxidant and hepatoprotective effects. Higher levels of scavenger activity on the 1,1-diphenyl-2-picrylhydrazyl radical, inhibition of deoxyribose oxidation and lipid peroxidation in vitro were detected for the ethyl acetate fraction (IC50∼4.3-32.3 mg/ml) followed by the crude extract (IC50∼14.2-98.0 mg/ml). The ethyl acetate fraction, again followed by the crude extract, showed high contents of total soluble polyphenols (3.6±0.2 and 2.1±0.2 GAE/mg, respectively) and presence of a quercetin-derived flavonoid identified as quercetin 3,3′-dimethyl ether 7-Ο-β-D-glycopyranoside. Both products were assayed for hepatoprotector effects against CCl4-induced liver injury in mice. Markers of oxidative stress and hepatic injury were evaluated. The results showed that the 10-day pretreatments (15 mg/kg, p.o.) protected the livers against injury by blocking CCl4-induced lipid peroxidation and protein carbonylation and the DNA fragmentation was decreased (∼60%). The pretreatments avoided the loss of the plasma ferric reducing/antioxidant power and the elevation of serum transaminases and lactate dehydrogenase activities. The results suggest that the main constituents responsible for the hepatoprotective effects with free radical scavenger power associated are well extracted by performing fractionation with ethyl acetate. The findings support the Brazilian traditional use of this plant and justify further evaluations for the therapeutic efficacy and safety of the constituents of the ethyl acetate fraction to treat some liver diseases.Keywords: Bidens pilosa L.; hydroethanol maceration; ethyl acetate fractionation; free radical scavenger; hepatoprotection; CCl4 toxicit
Identification of candidate genes for yeast engineering to improve bioethanol production in very high gravity and lignocellulosic biomass industrial fermentations
<p>Abstract</p> <p>Background</p> <p>The optimization of industrial bioethanol production will depend on the rational design and manipulation of industrial strains to improve their robustness against the many stress factors affecting their performance during very high gravity (VHG) or lignocellulosic fermentations. In this study, a set of <it>Saccharomyces cerevisiae </it>genes found, through genome-wide screenings, to confer resistance to the simultaneous presence of different relevant stresses were identified as required for maximal fermentation performance under industrial conditions.</p> <p>Results</p> <p>Chemogenomics data were used to identify eight genes whose expression confers simultaneous resistance to high concentrations of glucose, acetic acid and ethanol, chemical stresses relevant for VHG fermentations; and eleven genes conferring simultaneous resistance to stresses relevant during lignocellulosic fermentations. These eleven genes were identified based on two different sets: one with five genes granting simultaneous resistance to ethanol, acetic acid and furfural, and the other with six genes providing simultaneous resistance to ethanol, acetic acid and vanillin. The expression of <it>Bud31 </it>and <it>Hpr1 </it>was found to lead to the increase of both ethanol yield and fermentation rate, while <it>Pho85</it>, <it>Vrp1 </it>and <it>Ygl024w </it>expression is required for maximal ethanol production in VHG fermentations. Five genes, <it>Erg2</it>, <it>Prs3</it>, <it>Rav1</it>, <it>Rpb4 </it>and <it>Vma8</it>, were found to contribute to the maintenance of cell viability in wheat straw hydrolysate and/or the maximal fermentation rate of this substrate.</p> <p>Conclusions</p> <p>The identified genes stand as preferential targets for genetic engineering manipulation in order to generate more robust industrial strains, able to cope with the most significant fermentation stresses and, thus, to increase ethanol production rate and final ethanol titers.</p
Sleep and cardiometabolic comorbidities in the obstructive sleep apnoea-COPD overlap syndrome: data from the European Sleep Apnoea Database
Aim The impact of obstructive sleep apnoea (OSA)-COPD overlap syndrome (OVS) on sleep quality and cardiovascular outcomes has not been fully explored. We aimed to compare clinical and polysomnographic characteristics of patients with OVS versus patients with OSA, and to explore pathophysiological links between OVS and comorbidities. Study design and methods This cross-sectional analysis initially included data from 5600 patients with OSA and lung function in the European Sleep Apnoea Database. Two subgroups of patients with OSA (n=1018) or OVS (n=509) were matched (2:1) based on sex, age, body mass index and apnoea-hypopnea index at baseline. Results After matching, patients with OVS had more severe hypoxia, lower sleep efficiency and presented with higher prevalences of arterial hypertension, ischaemic heart disease and heart failure compared with patients with OSA. OVS was associated with a significant decrease in sleep efficiency (mean difference (beta) -3.0%, 95% CI -4.7 to -1.3) and in nocturnal mean peripheral oxyhaemoglobin saturation (S-pO2) (beta -1.1%, 95% CI -1.5 to -0.7). Further analysis revealed that a decrease in forced expiratory volume in 1 s and arterial oxygen tension was related to a decrease in sleep efficiency and in mean nocturnal S-pO2. A COPD diagnosis increased the odds of having heart failure by 1.75 (95% CI 1.15-2.67) and systemic hypertension by 1.36 (95% CI 1.07-1.73). Nocturnal hypoxia was strongly associated with comorbidities; the mean nocturnal S-pO2 and T90 (increase in time below S-pO2 of 90%) were associated with increased odds of systemic hypertension, diabetes and heart failure but the oxygen desaturation index was only related to hypertension and diabetes. Conclusion Patients with OVS presented with more sleep-related hypoxia, a reduced sleep quality and a higher risk for heart failure and hypertension.The ESADA study group received unrestricted funding grants from the Respironics and Resmed Foundations, and an unrestricted collaboration grant from Bayer AG
The modified patient enablement instrument: a Portuguese cross-cultural adaptation, validity and reliability study
"Article number: 16087"Enabling patients with asthma to obtain the knowledge, confidence and skills they need in order to assume a major role in the management of their disease is cost effective. It should be an integral part of any plan for long-term control of asthma. The modified Patient Enablement Instrument (mPEI) is an easily administered questionnaire that was adapted in the United Kingdom to measure patient enablement in asthma, but its applicability in Portugal is not known. Validity and reliability of questionnaires should be tested before use in settings different from those of the original version. The purpose of this study was to test the applicability of the mPEI to Portuguese asthma patients after translation and cross-cultural adaptation, and to verify the structural validity, internal consistency and reproducibility of the instrument. The mPEI was translated to Portuguese and back translated to English. Its content validity was assessed by a debriefing interview with 10 asthma patients. The translated instrument was then administered to a random sample of 142 patients with persistent asthma. Structural validity and internal consistency were assessed. For reproducibility analysis, 86 patients completed the instrument again 7 days later. Item-scale correlations and exploratory factor analysis were used to assess structural validity. Cronbach's alpha was used to test internal consistency, and the intra-class correlation coefficient was used for the analysis of reproducibility. All items of the Portuguese version of the mPEI were found to be equivalent to the original English version. There were strong item-scale correlations that confirmed construct validity, with a one component structure and good internal consistency (Cronbach's alpha >0.8) as well as high test-retest reliability (ICC=0.85). The mPEI showed sound psychometric properties for the evaluation of enablement in patients with asthma making it a reliable instrument for use in research and clinical practice in Portugal. Further studies are needed to confirm its responsiveness.Financial support for this work was provided by FEDER funds through the Operational Programme Competitiveness Factors-COMPETE and National Funds through FCT-Foundation for Science and Technology under the project POCI-01-0145-FEDER-007038, and by the project NORTE-01-0145-FEDER-000013, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through the European Regional Development Fund (ERDF).info:eu-repo/semantics/publishedVersio
Contact Manifolds, Contact Instantons, and Twistor Geometry
Recently, Kallen and Zabzine computed the partition function of a twisted
supersymmetric Yang-Mills theory on the five-dimensional sphere using
localisation techniques. Key to their construction is a five-dimensional
generalisation of the instanton equation to which they refer as the contact
instanton equation. Subject of this article is the twistor construction of this
equation when formulated on K-contact manifolds and the discussion of its
integrability properties. We also present certain extensions to higher
dimensions and supersymmetric generalisations.Comment: v3: 28 pages, clarifications and references added, version to appear
in JHE
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