132 research outputs found

    Magnetic Transformations in the Organic Conductor kappa-(BETS)2Mn[N(CN)2]3 at the Metal-Insulator Transition

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    A complex study of magnetic properties including dc magnetization, 1H NMR and magnetic torque measurements has been performed for the organic conductor kappa-(BETS)2Mn[N(CN)2]3 which undergoes a metal-insulator transition at T_MI~25K. NMR and the magnetization data indicate a transition in the manganese subsystem from paramagnetic to a frozen state at T_MI, which is, however, not a simple Neel type order. Further, a magnetic field induced transition resembling a spin flop has been detected in the torque measurements at temperatures below T_MI. This transition is most likely related to the spins of pi-electrons localized on the organic molecules BETS and coupled with the manganese 3d spins via exchange interaction.Comment: 6 pages, 5 Figures, 1 Table; Submitted to Phys.Rev.B (Nov.2010

    Multipurpose High Frequency Electron Spin Resonance Spectrometer for Condensed Matter Research

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    We describe a quasi-optical multifrequency ESR spectrometer operating in the 75-225 GHz range and optimized at 210 GHz for general use in condensed matter physics, chemistry and biology. The quasi-optical bridge detects the change of mm wave polarization at the ESR. A controllable reference arm maintains a mm wave bias at the detector. The attained sensitivity of 2x10^10 spin/G/(Hz)1/2, measured on a dilute Mn:MgO sample in a non-resonant probe head at 222.4 GHz and 300 K, is comparable to commercial high sensitive X band spectrometers. The spectrometer has a Fabry-Perot resonator based probe head to measure aqueous solutions, and a probe head to measure magnetic field angular dependence of single crystals. The spectrometer is robust and easy to use and may be operated by undergraduate students. Its performance is demonstrated by examples from various fields of condensed matter physics.Comment: submitted to Journal of Magnetic Resonanc

    Impact of asymptomatic urogenital tract infections on ejaculate parameters in infertile men with varicocele

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    Varicocele, a pathology developing in 15 % males, is associated with 30 % male infertility cases. The role of urogenital infections coinciding with varicocele in infertile men has not been studied in sufficient detail.Objective: to examine the effects of bacterial and viral infections on ejaculate parameters in infertile patients with varicocele. The study included 49 patients with infertility and varicocele and 26 healthy males undergoing prophylactic medical examination. Highlevel infection was recorded after examination of ejaculates and urethral scrapes of 49 patients: bacterial (30.6 %) and viral (14.3 %) pathogens. Quantitative analysis of viral DNA showed high contamination of ejaculates with herpes viruses (> 3 lg10/ml). Detailed analysis of spermatograms demonstrated a decrease in all basic parameters in patients with varicocele and infertility compared with those in healthy subjects. The presence of infectious agents had a statistically significant negative effect on ejaculate parameters. Spermiological examination revealed high level of sperm abnormalities (astenozoospermia, oligoteratozoospermia, and oligoastenoteratozoospermia) in patients with infertility, varicocele and bacterioviral infection of urogenital tract compared with uninfected infertile patients with varicocele. Laboratory tests for bacterial and viral infections should be recommended in infertility associated with varicocele even in the absence of clinical signs of these infections. Quantitative analysis of urogenital pathogens allows one to determine the necessity of etiotherapy of hidden infection and to monitor the effectiveness of treatment

    ОСОБЕННОСТИ ТЕЧЕНИЯ ИНФЕКЦИИ, ВЫЗВАННОЙ ВИРУСОМ ГЕРПЕСА ЧЕЛОВЕКА 6 ТИПА, У ДЕТЕЙ РАННЕГО ВОЗРАСТА НА ФОНЕ ОСТРОЙ РЕСПИРАТОРНОЙ ВИРУСНОЙ ИНФЕКЦИИ

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    We examined 95 children aged from 5 months till 3 years (middle age 1,7 ±1,1), who were admitted in children's infectious department of theClinicalInfectionsHospital№1 by diagnosis acute respiratory virus infection in the height of disease. Anti-genes of sharp respiratory viruses by the IF method, markers of HHV-6 type, and also a cytomegalovirus of the person (CMV) and Epstein-Barre's virus the ELISA methods and PTsR-rv are studied. Respiratory viruses are found among the hospitalized children in 46,3% of cases, from them paraflu (32,6%) in comparison with flu (9,5%) and a respiratornosintsitialny virus (4,2%), р < 0,05 statistically significantly is more often revealed. Markers of HHV are revealed at 73,7% of children. During the mixed infection HHV-6 markers are found in the vast majority of children (79,4%) in combination with this or that representative of Herpesviridae, is statistically significantly more often with CMV(16,8%), р < 0,05. DNA of HHV-6 is statistically significantly more often (41%) and with more viral load (53 400 copies/ml ) is revealed in a saliva in comparison with blood and urine. DNA of HHV-6 ina saliva statistically significantly is defined among the children visiting child care centers more often, than at unorganized children (72% against 40,4%, р = 0,0001) that testifies about a horizontal transmission of infection. It is observed that markers of HHV-6 are defined statistically significantly more often among children aged from 7 till 12 months (50%) and among children older by 1 year (49,2%) in comparison with children aged from 0 till 6 months (10%), р < 0,05. It is shown that among children of an early age the exanthema at HHV-6-of an infection is associated with presence of DNA of HHV-6 with high concentration (more than 120 000 copies/ml) in blood.Обследовано 95 детей в возрасте от 5 месяцев до 3-х лет (средний возраст 1,7 ± 1,1 года), поступавших в детское инфекционное отделение КИБ № 1 с диагнозом ОРВИ в разгаре заболевания. Изучены антигены острых респираторных вирусов методом нИФ, маркеры ВГЧ-6 типа, а также цитомегаловируса человека (ЦМВ) и вируса Эпштейна-Барр (ВЭБ) методами ИФА и ПЦР-рв. У госпитализированных детей в 46,3% случаев обнаружены респираторные вирусы, из них статистически значимо чаще выявлен парагрипп (32,6%) по сравнению с гриппом (9,5%) и респираторно-синцитиальным вирусом (4,2%), р < 0,05. Маркеры ГВИ выявлены у 73,7% детей. При смешанной инфекции у подавляющего большинства детей (79,4%) обнаружены маркеры ВГЧ-6 в сочетании с тем или иным представителем Herpesviridae, чаще — с ЦМВ (16,8%), р < 0,05. ДНК ВГЧ-6 статистически значимо чаще (41%) и с большей вирусной нагрузкой (53 400 копий/мл) выявлена в слюне по сравнению с кровью и мочой. ДНК ВГЧ-6 в слюне чаще определяется у детей, посещающих детские учреждения, чем у неорганизованных детей (72% против 40,4%, р = 0,0001), что свидетельствует о горизонтальной передачи инфекции. Установлено, что маркеры ВГЧ-6 выявляются чаще у детей в возрасте от 7 до 12 месяцев (50%) и у детей старше 1 года (49,2%) по сравнению с детьми в возрасте от 0 до 6 месяцев (10%), р < 0,05. Показано, что у детей раннего возраста экзантема при ВГЧ-6-инфекции ассоциирована с присутствием ДНК ВГЧ-6 с высокой концентрацией (более 1000 копий/106) в крови.

    A locus at 19q13.31 significantly reduces the <em>ApoE</em> ε4 risk for Alzheimer\u27s Disease in African Ancestry

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    Copyright: \ua9 2022 Rajabli et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. African descent populations have a lower Alzheimer disease risk from ApoE ε4 compared to other populations. Ancestry analysis showed that the difference in risk between African and European populations lies in the ancestral genomic background surrounding the ApoE locus (local ancestry). Identifying the mechanism(s) of this protection could lead to greater insight into the etiology of Alzheimer disease and more personalized therapeutic intervention. Our objective is to follow up the local ancestry finding and identify the genetic variants that drive this risk difference and result in a lower risk for developing Alzheimer disease in African ancestry populations. We performed association analyses using a logistic regression model with the ApoE ε4 allele as an interaction term and adjusted for genome-wide ancestry, age, and sex. Discovery analysis included imputed SNP data of 1,850 Alzheimer disease and 4,331 cognitively intact African American individuals. We performed replication analyses on 63 whole genome sequenced Alzheimer disease and 648 cognitively intact Ibadan individuals. Additionally, we reproduced results using whole-genome sequencing of 273 Alzheimer disease and 275 cognitively intact admixed Puerto Rican individuals. A further comparison was done with SNP imputation from an additional 8,463 Alzheimer disease and 11,365 cognitively intact non-Hispanic White individuals. We identified a significant interaction between the ApoE ε4 allele and the SNP rs10423769_A allele, (β = -0.54,SE = 0.12,p-value = 7.50x10-6) in the discovery data set, and replicated this finding in Ibadan (β = -1.32,SE = 0.52,p-value = 1.15x10-2) and Puerto Rican (β = -1.27,SE = 0.64,p-value = 4.91x10-2) individuals. The non-Hispanic Whites analyses showed an interaction trending in the “protective” direction but failing to pass a 0.05 significance threshold (β = -1.51,SE = 0.84,p-value = 7.26x10-2). The presence of the rs10423769_A allele reduces the odds ratio for Alzheimer disease risk from 7.2 for ApoE ε4/ε4 carriers lacking the A allele to 2.1 for ApoE ε4/ε4 carriers with at least one A allele. This locus is located approximately 2 mB upstream of the ApoE locus, in a large cluster of pregnancy specific beta-1 glycoproteins on chromosome 19 and lies within a long noncoding RNA, ENSG00000282943. This study identified a new African-ancestry specific locus that reduces the risk effect of ApoE ε4 for developing Alzheimer disease. The mechanism of the interaction with ApoEε4 is not known but suggests a novel mechanism for reducing the risk for ε4 carriers opening the possibility for potential ancestry-specific therapeutic intervention

    Expiratory flow rate, breath hold and anatomic dead space influence electronic nose ability to detect lung cancer

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    BACKGROUND: Electronic noses are composites of nanosensor arrays. Numerous studies showed their potential to detect lung cancer from breath samples by analysing exhaled volatile compound pattern ("breathprint"). Expiratory flow rate, breath hold and inclusion of anatomic dead space may influence the exhaled levels of some volatile compounds; however it has not been fully addressed how these factors affect electronic nose data. Therefore, the aim of the study was to investigate these effects. METHODS: 37 healthy subjects (44 +/- 14 years) and 27 patients with lung cancer (60 +/- 10 years) participated in the study. After deep inhalation through a volatile organic compound filter, subjects exhaled at two different flow rates (50 ml/sec and 75 ml/sec) into Teflon-coated bags. The effect of breath hold was analysed after 10 seconds of deep inhalation. We also studied the effect of anatomic dead space by excluding this fraction and comparing alveolar air to mixed (alveolar + anatomic dead space) air samples. Exhaled air samples were processed with Cyranose 320 electronic nose. RESULTS: Expiratory flow rate, breath hold and the inclusion of anatomic dead space significantly altered "breathprints" in healthy individuals (p 0.05). These factors also influenced the discrimination ability of the electronic nose to detect lung cancer significantly. CONCLUSIONS: We have shown that expiratory flow, breath hold and dead space influence exhaled volatile compound pattern assessed with electronic nose. These findings suggest critical methodological recommendations to standardise sample collections for electronic nose measurements

    Developmental malformation of the corpus callosum: a review of typical callosal development and examples of developmental disorders with callosal involvement

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    This review provides an overview of the involvement of the corpus callosum (CC) in a variety of developmental disorders that are currently defined exclusively by genetics, developmental insult, and/or behavior. I begin with a general review of CC development, connectivity, and function, followed by discussion of the research methods typically utilized to study the callosum. The bulk of the review concentrates on specific developmental disorders, beginning with agenesis of the corpus callosum (AgCC)—the only condition diagnosed exclusively by callosal anatomy. This is followed by a review of several genetic disorders that commonly result in social impairments and/or psychopathology similar to AgCC (neurofibromatosis-1, Turner syndrome, 22q11.2 deletion syndrome, Williams yndrome, and fragile X) and two forms of prenatal injury (premature birth, fetal alcohol syndrome) known to impact callosal development. Finally, I examine callosal involvement in several common developmental disorders defined exclusively by behavioral patterns (developmental language delay, dyslexia, attention-deficit hyperactive disorder, autism spectrum disorders, and Tourette syndrome)

    Catalysis Research of Relevance to Carbon Management: Progress, Challenges, and Opportunities

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