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https://www.readbyqxmd.com/read/28323482/constraints-on-the-early-terrestrial-surface-uv-environment-relevant-to-prebiotic-chemistry
#1
Sukrit Ranjan, Dimitar D Sasselov
The UV environment is a key boundary condition to abiogenesis. However, considerable uncertainty exists as to planetary conditions and hence surface UV at abiogenesis. Here, we present two-stream multilayer clear-sky calculations of the UV surface radiance on Earth at 3.9 Ga to constrain the UV surface fluence as a function of albedo, solar zenith angle (SZA), and atmospheric composition. Variation in albedo and latitude (through SZA) can affect maximum photoreaction rates by a factor of >10.4; for the same atmosphere, photoreactions can proceed an order of magnitude faster at the equator of a snowball Earth than at the poles of a warmer world...
March 2017: Astrobiology
https://www.readbyqxmd.com/read/28323481/the-emergence-of-life-as-a-first-order-phase-transition
#2
Cole Mathis, Tanmoy Bhattacharya, Sara Imari Walker
It is well known that life on Earth alters its environment over evolutionary and geological timescales. An important open question is whether this is a result of evolutionary optimization or a universal feature of life. In the latter case, the origin of life would be coincident with a shift in environmental conditions. Here we present a model for the emergence of life in which replicators are explicitly coupled to their environment through the recycling of a finite supply of resources. The model exhibits a dynamic, first-order phase transition from nonlife to life, where the life phase is distinguished by selection on replicators...
March 2017: Astrobiology
https://www.readbyqxmd.com/read/28323410/zno-quantum-dots-decorated-zn2sno4-nanowire-heterojunction-photodetectors-with-drastic-performance-enhancement-and-flexible-ultraviolet-image-sensors
#3
Ludong Li, Leilei Gu, Zheng Lou, Zhiyong Fan, Guozhen Shen
Here we report fabrication of high-performance ultraviolet photodetectors based on a unique heterojunction device structure in which ZnO quantum dots were used to decorate Zn2SnO4 nanowires. Systematic investigations have shown their ultrahigh light-to-dark current ratio (up to 6.8 × 104), specific detectivity (up to 9.0×1017 Jones), photoconductive gain (up to 1.1 × 107), fast response, and excellent stability. Compared with a pristine Zn2SnO4 nanowire, a quantum dots decorated nanowire demonstrated about 10 times higher photocurrent and responsivity...
March 21, 2017: ACS Nano
https://www.readbyqxmd.com/read/28320116/in-vitro-non-viral-murine-pro-neurotrophin-3-gene-transfer-into-rat-bone-marrow-stromal-cells
#4
Shahram Darabi, Taki Tiraihi, AliReza Delshad, Majid Sadeghizadeh, Wisam Khalil, Taher Taheri
Neurotrophin 3 (NT-3) is an important factor for promoting prenatal neural development, as well as regeneration, axogenesis and plasticity in postnatal life. Therapy with NT-3 was reported to improve the condition of patients suffering from degenerative diseases and traumatic injuries, however, the disadvantage of NT-3 protein delivery is its short half-life, thus our alternative approach is the use of NT-3 gene therapy. In this study, the bone marrow stromal cells (BMSCs) were isolated from adult rats, cultured for 4 passages and transfected with either pEGFP-N1 or a constructed vector containing murine proNT-3 (pSecTag2/HygroB-murine proNT-3) using Lipofectamine 2000 followed by Hygromycin B (200mg/kg)...
April 15, 2017: Journal of the Neurological Sciences
https://www.readbyqxmd.com/read/28318965/the-social-benefits-of-weee-re-use-schemes-a-cost-benefit-analysis-for-pcs-in-spain
#5
Xose Manuel González, Miguel Rodríguez, Yolanda Pena-Boquete
One goal of the new European legislation set out in WEEE Directive 2012/19/UE is the promotion of WEEE re-use schemes. However, some authors are rather sceptical about the contribution of WEEE re-use schemes to improve resource efficiency. In order to evaluate and to design adequate policy instruments, some authors recommend the cost-benefit analysis (CBA) as a compulsory first step. In this context, the main contribution of this paper is to enlarge the empirical literature by providing a CBA of re-use schemes versus recycling processes of PCs...
March 16, 2017: Waste Management
https://www.readbyqxmd.com/read/28318491/late-life-depression-hippocampal-volumes-and-hypothalamic-pituitary-adrenal-axis-regulation-a-systematic-review-and-meta-analysis
#6
Mirjam I Geerlings, Lotte Gerritsen
BACKGROUND: We systematically reviewed and meta-analyzed the association of late-life depression (LLD) with hippocampal volume (HCV) and total brain volume (TBV), and of cortisol levels with HCV, including subgroup analyses of depression characteristics and methodological aspects. METHODS: We searched PubMed and Embase for original studies that examined the cross-sectional relationship between LLD and HCV or TBV, and 46 studies fulfilled the inclusion criteria. Standardized mean differences (Hedges' g) between LLD and control subjects were calculated from crude or adjusted brain volumes using random effects...
January 27, 2017: Biological Psychiatry
https://www.readbyqxmd.com/read/28317816/hemophagocytic-syndrome-secondary-to-tuberculosis-at-24-week-gestation
#7
Alexandra Arteaga Fernández, David Fernández de Velasco Pérez, M C Jiménez Fournier, J C Moreno Del Prado, B Paraíso Torras, M L Cañete Palomo
Hemophagocytic syndrome is a life-threatening disease characterized by the uncontrolled activation of macrophages, resulting in hemophagocytosis of blood cells in the bone marrow. A 20-year-old gravida at 23-week and 5-day gestation was admitted to hospital to evaluate fever up to 104°F of unknown origin, moderate cytopenia, and elevated levels of liver enzymes. Bone marrow biopsy confirmed hemophagocytic syndrome, and polymerase chain reaction came back positive for Mycobacterium tuberculosis. Supportive care and tuberculosis treatment resulted in clinical improvement...
January 2017: International Journal of Mycobacteriology
https://www.readbyqxmd.com/read/28316928/double-aortic-arch-diagnosed-in-a-44-year-old-woman-with-recurring-respiratory-infections
#8
Ana Fenández-Tena, Cristina Martínez-González
Complete vascular rings are originated because of the persistence of the fourth aortic arches, which surround the trachea and esophagus partially or completely, compressing them. The most common type of complete vascular ring is the double aortic arch. Symptoms usually appear in the first months of life, and are provoked by esophageal and tracheal compression. The diagnosis is usually made through the chest X-ray and the esophagogram in patients with dysphagia. We present a case in which the diagnosis of a double aortic arch was made in adulthood, suspected through a spirometry test and a chest X-ray...
2017: Respiratory Medicine Case Reports
https://www.readbyqxmd.com/read/28315699/the-neglected-functions-of-intrinsically-disordered-proteins-and-the-origin-of-life
#9
REVIEW
Laurent Jaeken
The example of gelatine shows that extended proteins behave quite differently than globular ones: with water they form a gel. Historically the colloid view of protoplasm was discredited in favour of membrane-(pump)-theory (MPT), but unjustified. In his association-induction hypothesis Ling demonstrates that MPT is full of contradictions and that the colloid view has to be re-considered. In that case IDP's play a crucial role in this. What Ling calls the 'living state' consists of the unitary protoplasmic structure from which it was experimentally demonstrated that it can survive and keep Na(+) and K(+) concentrations without a delineating membrane...
March 15, 2017: Progress in Biophysics and Molecular Biology
https://www.readbyqxmd.com/read/28315258/mechanisms-of-iron-sensing-and-regulation-in-the-yeast-saccharomyces-cerevisiae
#10
REVIEW
María Teresa Martínez-Pastor, Ana Perea-García, Sergi Puig
Iron is a redox active element that functions as an essential cofactor in multiple metabolic pathways, including respiration, DNA synthesis and translation. While indispensable for eukaryotic life, excess iron can lead to oxidative damage of macromolecules. Therefore, living organisms have developed sophisticated strategies to optimally regulate iron acquisition, storage and utilization in response to fluctuations in environmental iron bioavailability. In the yeast Saccharomyces cerevisiae, transcription factors Aft1/Aft2 and Yap5 regulate iron metabolism in response to low and high iron levels, respectively...
April 2017: World Journal of Microbiology & Biotechnology
https://www.readbyqxmd.com/read/28314780/non-coding-rnas-the-dark-side-of-nuclear-mitochondrial-communication
#11
REVIEW
Roberto Vendramin, Jean-Christophe Marine, Eleonora Leucci
Mitochondria are critical hubs for the integration of several key metabolic processes implicated in cell growth and survival. They originated from bacterial ancestors through endosymbiosis, following the transfer of more than 90% of their endosymbiont genome to the host cell nucleus. Over time, a mutually beneficial symbiotic relationship has been established, which relies on continuous and elaborate signaling mechanisms between this life-essential organelle and its host. The ability of mitochondria to signal their functional state and trigger compensatory and adaptive cellular responses has long been recognized, but the underlying molecular mechanisms involved have remained poorly understood...
March 17, 2017: EMBO Journal
https://www.readbyqxmd.com/read/28314518/the-interface-between-chronic-fatigue-syndrome-and-depression-a-psychobiological-and-neurophysiological-conundrum
#12
Derek Larkin, Colin R Martin
The chronic fatigue syndrome (CFS) remains a contentious and controversial presentation despite decades of systematic research from a variety of medical specialties and associated disciplines. Variously championed as a condition of immunological, neurological, neurophysiological, psychiatric or psychological origin, consensus on a cogent and evidenced-based pathway has yet to be achieved. Irrespective of the ambiguity regarding aetiology, what is incontrovertible is the experience of significant depression, which often accompanies this most distressing clinical presentation...
March 14, 2017: Neurophysiologie Clinique, Clinical Neurophysiology
https://www.readbyqxmd.com/read/28314139/patients-experiences-of-atrial-fibrillation-and-non-vitamin-k-antagonist-oral-anticoagulants-noacs-and-their-educational-needs-a-qualitative-study
#13
Danielle E Clarkesmith, Gregory Y H Lip, Deirdre A Lane
PURPOSE: Qualitative research on atrial fibrillation (AF) patient's experiences and perceptions of taking the non-vitamin K antagonist oral anticoagulants (NOACs) for stroke prevention is limited. This study explores patients' experiences of dabigatran and their recommendations for development of educational materials. PATIENTS AND METHODS: Semi-structured individual interviews with 8 warfarin-naive and 8 warfarin-experienced AF patients, using qualitative deductive thematic analysis...
March 7, 2017: Thrombosis Research
https://www.readbyqxmd.com/read/28304287/triceps-and-subscapular-skinfold-in-men-aged-40-65-and-dementia-prevalence-36-years-later
#14
Ramit Ravona-Springer, Michal Schnaider-Beeri, Uri Goldbourt
BACKGROUND: The relationship of obesity with risk for dementia is complex and may change with age. OBJECTIVE: To analyze the relationship between measures of obesity at age 40-65 and dementia prevalence in survivors 36 years later. METHODS: Obesity-related measures of triceps and subscapular skinfold thickness were assessed in 1963 in n = 9,760 men aged 40-65 participating in the Israel Ischemic Heart Disease study. Cognitive evaluation and assessment of dementia prevalence were performed in n = 1,643 participants of the original cohort who survived until 1999/2000 (age ≥76 years) and had anthropometric measures in 1963...
March 18, 2017: Journal of Alzheimer's Disease: JAD
https://www.readbyqxmd.com/read/28303705/the-sense-of-life-satisfaction-versus-dietary-choices-of-young-women-doing-fitness-for-recreational-purposes
#15
Maria Gacek
Background: : The health potential of a person can be improved thanks to recreational physical activity and rational diet. The sense of life satisfaction is also one of significant health resources. Objective: The aim of the study was to analyze the relations between the level of life satisfaction and the frequency of consuming selected products in the group of young women who engage in fitness for recreational purposes. Material and Methods: The study involved 200 young women (20-30 years old) who regularly do recreational physical activity in fitness clubs in Małopolska...
2017: Roczniki Państwowego Zakładu Higieny
https://www.readbyqxmd.com/read/28302638/innovative-approach-for-self-management-and-social-welfare-of-children-with-cystic-fibrosis-in-europe-development-validation-and-implementation-of-an-mhealth-tool-mycyfapp
#16
Joaquim Calvo-Lerma, Celia P Martinez-Jimenez, Juan-Pablo Lázaro-Ramos, Ana Andrés, Paula Crespo-Escobar, Erlend Stav, Cornelia Schauber, Lucia Pannese, Jessie M Hulst, Lucrecia Suárez, Carla Colombo, Celeste Barreto, Kris de Boeck, Carmen Ribes-Koninckx
INTRODUCTION: For the optimal management of children with cystic fibrosis, there are currently no efficient tools for the precise adjustment of pancreatic enzyme replacement therapy, either for advice on appropriate dietary intake or for achieving an optimal nutrition status. Therefore, we aim to develop a mobile application that ensures a successful nutritional therapy in children with cystic fibrosis. METHODS AND ANALYSIS: A multidisciplinary team of 12 partners coordinate their efforts in 9 work packages that cover the entire so-called 'from laboratory to market' approach by means of an original and innovative co-design process...
March 16, 2017: BMJ Open
https://www.readbyqxmd.com/read/28302350/primary-prophylaxis-in-haemophilia-care-guideline-update-2016
#17
Kathelijn Fischer, Rolf Ljung
This paper reviews the current status on recommendations or guidelines for primary prophylaxis based on recent published papers from organizations or group of experts as well as some original key papers. A rather uniform view exists that prophylaxis should be initiated at an early age before or after no more than a single joint bleed and, if possible, preferably be continued for life. The dose and dose frequency of prophylaxis is dependent on the goal of treatment, bleeding phenotype, compliance, venous access and economic resources in the health care system and should be tailored individually based on clinical outcome and pharmacokinetics...
February 17, 2017: Blood Cells, Molecules & Diseases
https://www.readbyqxmd.com/read/28302076/uropathogenic-escherichia-coli-pathogenicity-islands-and-other-expec-virulence-genes-may-contribute-to-the-genome-variability-of-enteroinvasive-e-coli
#18
Laís Cristina da Silva, Ana Carolina de Mello Santos, Rosa Maria Silva
BACKGROUND: Enteroinvasive Escherichia coli (EIEC) may be the causative agent of part of those million cases of diarrhea illness reported worldwide every year and attributable to Shigella. That is because both enteropathogens have many common characteristics that difficult their identification either by traditional microbiological methods or by molecular tools used in the clinical laboratory settings. While Shigella has been extensively studied, EIEC remains barely characterized at the molecular level...
March 16, 2017: BMC Microbiology
https://www.readbyqxmd.com/read/28301842/early-life-nutritional-programming-of-health-and-disease-in-the-gambia
#19
Sophie E Moore
BACKGROUND: Exposures during early life are increasingly being recognised as factors that play an important role in the aetiology of chronic non-communicable diseases (NCDs). The "Developmental Origins of Health and Disease" (DOHaD) hypothesis asserts that adverse early-life exposures - most notably unbalanced nutrition - leads to an increased risk for a range of NCDs and that disease risk is highest when there is a "mismatch" between the early- and later-life environments. Thus, the DOHaD hypothesis would predict highest risk in settings undergoing a rapid nutrition transition...
March 17, 2017: Annals of Nutrition & Metabolism
https://www.readbyqxmd.com/read/28301839/early-programming-of-obesity-throughout-the-life-course-a-metabolomics-perspective
#20
Sebastian Rauschert, Franca F Kirchberg, Linda Marchioro, Berthold Koletzko, Christian Hellmuth, Olaf Uhl
BACKGROUND: Over the last decades, research on early life risk factors for obesity and its comorbidities in early life has gained attention within the field of developmental origins of health and diseases. Metabolomics studies that are trying to find early life biomarker and intervention targets for the early development of obesity and associated cardiovascular diseases could help break the inter-generational cycle of obesity. SUMMARY: Metabolomics studies in the field of early programming are scarce and causality is lacking at this stage, as most of the studies are cross-sectional...
March 17, 2017: Annals of Nutrition & Metabolism
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