181 research outputs found
Reduced-bias estimator of the Conditional Tail Expectation of heavy-tailed distributions
International audienceSeveral risk measures have been proposed in the literature. In this paper, we focus on the estimation of the Conditional Tail Expectation (CTE). Its asymptotic normality has been first established in the literature under the classical assumption that the second moment of the loss variable is finite, this condition being very restrictive in practical applications. Such a result has been extended by Necir {\it et al.} (2010) in the case of infinite second moment. In this framework, we propose a reduced-bias estimator of the CTE. We illustrate the efficiency of our approach on a small simulation study and a real data analysis
New national and regional bryophyte records, 52
Marchantia paleacea is a new species for the Umbria Region and is rare in central and southern Italy.
This record is in a Site of Community Importance (SCI) IT5220017 and a Special Area of Conservation (SAC) of the Natura 2000 EU-wide network due to the presence of the 7220* ‘Petrifying springs with tufa formation (Cratoneurion)’ Annexe I priority habitat. The particular environment, with a gorge and waterfall, created a very special microclimate that allowed the establishment of interesting liverworts and mosses
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An update on vitamin B12-related gene polymorphisms and B12 status.
Vitamin B12 is an essential micronutrient in humans needed for health maintenance. Deficiency of vitamin B12 has been linked to dietary, environmental and genetic factors. Evidence for the genetic basis of vitamin B12 status is poorly understood. However, advancements in genomic techniques have increased the knowledge-base of the genetics of vitamin B12 status. Based on the candidate gene and genome-wide association (GWA) studies, associations between genetic loci in several genes involved in vitamin B12 metabolism have been identified. The objective of this literature review was to identify and discuss reports of associations between single-nucleotide polymorphisms (SNPs) in vitamin B12 pathway genes and their influence on the circulating levels of vitamin B12. Relevant articles were obtained through a literature search on PubMed through to May 2017. An article was included if it examined an association of a SNP with serum or plasma vitamin B12 concentration. Beta coefficients and odds ratios were used to describe the strength of an association, and a < 0.05 was considered as statistically significant. Two reviewers independently evaluated the eligibility for the inclusion criteria and extracted the data. From 23 studies which fulfilled the selection criteria, 16 studies identified SNPs that showed statistically significant associations with vitamin B12 concentrations. Fifty-nine vitamin B12-related gene polymorphisms associated with vitamin B12 status were identified in total, from the following populations: African American, Brazilian, Canadian, Chinese, Danish, English, European ancestry, Icelandic, Indian, Italian, Latino, Northern Irish, Portuguese and residents of the USA. Overall, the data analyzed suggests that ethnic-specific associations are involved in the genetic determination of vitamin B12 concentrations. However, despite recent success in genetic studies, the majority of identified genes that could explain variation in vitamin B12 concentrations were from Caucasian populations. Further research utilizing larger sample sizes of non-Caucasian populations is necessary in order to better understand these ethnic-specific associations
Neutrons describe ectoine effects on water H-bonding and hydration around a soluble protein and a cell membrane
Understanding adaptation to extreme environments remains a challenge of high biotechnological potential for fundamental molecular biology. The cytosol of many microorganisms, isolated from saline environments, reversibly accumulates molar concentrations of the osmolyte ectoine to counterbalance fluctuating external salt concentrations. Although they have been studied extensively by thermodynamic and spectroscopic methods, direct experimental structural data have, so far, been lacking on ectoine-water-protein interactions. In this paper, in vivo deuterium labeling, small angle neutron scattering, neutron membrane diffraction and inelastic scattering are combined with neutron liquids diffraction to characterize the extreme ectoine-containing solvent and its effects on purple membrane of H. salinarum and E. coli maltose binding protein. The data reveal that ectoine is excluded from the hydration layer at the membrane surface and does not affect membrane molecular dynamics, and prove a previous hypothesis that ectoine is excluded from a monolayer of dense hydration water around the soluble protein. Neutron liquids diffraction to atomic resolution shows how ectoine enhances the remarkable properties of H-bonds in water-properties that are essential for the proper organization, stabilization and dynamics of biological structures
Composition and Distribution of Mosquito Vectors in a Peri-Urban Community Surrounding an Institution of Learning in Lafia Metropolis, Nasarawa State, Central Nigeria
Vector surveillance is very key in solving mosquito-borne health problems in Nigeria. To this end, the composition and distribution of mosquito vectors in a peri-urban community surrounding an institution of learning in Lafia metropolis, Nasarawa State, Central Nigeria was carried out between December 2016 and June 2017. The Prokopack Aspirator was used to collect indoor resting mosquitoes between 6:00 a.m. and 9:00 a.m. from 30 randomly selected houses. Mosquitoes collected were knocked down and transferred into a well labelled petri-dish and taken to the laboratory for processing. A total of 664 mosquitoes were collected which spread across Culex quinquefasciatus 572 (86.14%), Anopheles gambiae 88 (13.25%) and Aedes aegypti 4 (0.60%). The abundance of mosquitoes in relation to seasons, species, sex, abdominal conditions as well as transmission indices across seasons significantly varied (P 0.05). The inhabitants of the area should ensure that all drainages flow through so as to reduce mosquito breeding grounds. Also, members of the community should always protect themselves by sleeping under insecticide treated bed nets
Clinical Characterization and Outcomes of Human Clade IIb Mpox Virus Disease: A European Multicenter Mpox Observational Cohort Study (MOSAIC)
Background The global mpox outbreak that started in May 2022 was caused by a novel clade IIb variant of the mpox virus (Orthopoxvirus monkeypox, MPXV). It differed from the traditional Western and Central Africa disease in transmission patterns and clinical presentation. Methods To address the need for detailed clinical and virologic data, we conducted an observational cohort study (MOSAIC) during May 2022-July 2023 in individuals with confirmed MPXV infection enrolled in 6 European countries. Case management decisions were left to the attending physician. Participants were monitored for up to 6 months for clinical signs/symptoms and clinical and virologic outcomes through hospital visits, phone interviews, and self-administered questionnaires. Outcomes included time to lesion resolution, clinical status, and virus clearance. Results The 518 participants not receiving any specific treatment ("untreated") were diagnosed a median 5 days from symptom onset; 90% were managed as outpatients. Lesions were mostly cutaneous (88%) and perigenital (74%). By day 14 from the first polymerase chain reaction (PCR)-positive sample, 39% had resolved lesions. Time to 95% unculturable virus was longest in cutaneous lesions (52 days). A putative systemic antiviral was available for 57 participants, 44% as inpatients; 34% and 58% had resolved lesions by day 14 from the first PCR-positive sample and from treatment start, respectively. Time to 95% unculturable virus was 60 days in skin and oropharynx. No death or recrudescence occurred by day 180. Conclusions MOSAIC provides comprehensive insights into the clinical and virologic characteristics of mpox caused by the clade IIb variant. The study forms the basis of clinical characterization for ongoing mpox outbreaks. The Author(s) 2025
Phase Behavior of Amphiphilic Diblock Co-oligomers with Nonionic and Ionic Hydrophilic Groups
Ex vivo susceptibility and genotyping of Plasmodium falciparum isolates from Pikine, Senegal
Socializing One Health: an innovative strategy to investigate social and behavioral risks of emerging viral threats
In an effort to strengthen global capacity to prevent, detect, and control infectious diseases in animals and people, the United States Agency for International Development’s (USAID) Emerging Pandemic Threats (EPT) PREDICT project funded development of regional, national, and local One Health capacities for early disease detection, rapid response, disease control, and risk reduction. From the outset, the EPT approach was inclusive of social science research methods designed to understand the contexts and behaviors of communities living and working at human-animal-environment interfaces considered high-risk for virus emergence. Using qualitative and quantitative approaches, PREDICT behavioral research aimed to identify and assess a range of socio-cultural behaviors that could be influential in zoonotic disease emergence, amplification, and transmission. This broad approach to behavioral risk characterization enabled us to identify and characterize human activities that could be linked to the transmission dynamics of new and emerging viruses. This paper provides a discussion of implementation of a social science approach within a zoonotic surveillance framework. We conducted in-depth ethnographic interviews and focus groups to better understand the individual- and community-level knowledge, attitudes, and practices that potentially put participants at risk for zoonotic disease transmission from the animals they live and work with, across 6 interface domains. When we asked highly-exposed individuals (ie. bushmeat hunters, wildlife or guano farmers) about the risk they perceived in their occupational activities, most did not perceive it to be risky, whether because it was normalized by years (or generations) of doing such an activity, or due to lack of information about potential risks. Integrating the social sciences allows investigations of the specific human activities that are hypothesized to drive disease emergence, amplification, and transmission, in order to better substantiate behavioral disease drivers, along with the social dimensions of infection and transmission dynamics. Understanding these dynamics is critical to achieving health security--the protection from threats to health-- which requires investments in both collective and individual health security. Involving behavioral sciences into zoonotic disease surveillance allowed us to push toward fuller community integration and engagement and toward dialogue and implementation of recommendations for disease prevention and improved health security
AVALIAÇÃO DA INCERTEZA DE MEDIÇÃO NA CALIBRAÇÃO DE MEDIDOR DE VAZÃO DE LÍQUIDOS PELO MÉTODO GRAVIMÉTRICO
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