Critical sound attenuation in a diluted Ising system

The field-theoretic description of dynamical critical effects of the influence of disorder on acoustic anomalies near the temperature of the second-order phase transition is considered for three-dimensional Ising-like systems. Calculations of the sound attenuation in pure and dilute Ising-like systems near the critical point are presented. The dynamical scaling function for the critical attenuation coefficient is calculated. The influence of quenched disorder on the asymptotic behaviour of the critical ultrasonic anomalies is discussed.Comment: 12 RevTeX pages, 4 figure

Modulational instability of bright solitary waves in incoherently coupled nonlinear Schr\"odinger equations

We present a detailed analysis of the modulational instability (MI) of ground-state bright solitary solutions of two incoherently coupled nonlinear Schr\"odinger equations. Varying the relative strength of cross-phase and self-phase effects we show existence and origin of four branches of MI of the two-wave solitary solutions. We give a physical interpretation of our results in terms of the group velocity dispersion (GVD) induced polarization dynamics of spatial solitary waves. In particular, we show that in media with normal GVD spatial symmetry breaking changes to polarization symmetry breaking when the relative strength of the cross-phase modulation exceeds a certain threshold value. The analytical and numerical stability analyses are fully supported by an extensive series of numerical simulations of the full model.Comment: Physical Review E, July, 199

Mid-infrared supercontinuum generation using dispersion-engineered Ge11.5As24Se64.5 chalcogenide channel waveguide

We numerically investigate mid-infrared supercontinuum (SC) generation in dispersion-engineered, air-clad, Ge11.5As24Se64.5 chalcogenide-glass channel waveguides employing two different materials, Ge11.5As24S64.5 or MgF2 glass for their lower cladding. We study the effect of waveguide parameters on the bandwidth of the SC at the output of 1-cm-long waveguide. Our results show that output can vary over a wide range depending on its design and the pump wavelength employed. At the pump wavelength of 2 µm the SC never extended beyond 4.5 µm for any of our designs. However, supercontinuum could be extended to beyond 5 µm for a pump wavelength of 3.1 µm. A broadband SC spanning from 2 µm to 6 µm and extending over 1.5 octave could be generated with a moderate peak power of 500 W at a pump wavelength of 3.1 µm using an air-clad, all-chalcogenide, channel waveguide. We show that SC can be extended even further when MgF2 glass is used for the lower cladding of chalcogenide waveguide. Our numerical simulations produced SC spectra covering the wavelength range 1.8-7.7 µm (> two octaves) by using this geometry. Both ranges exceed the broadest SC bandwidths reported so far. Moreover, we realize it using 3.1 µm pump source and relatively low peak power pulses. By employing the same pump source, we show that SC spectra can cover a wavelength range of 1.8-11 µm (> 2.5 octaves) in a channel waveguide employing MgF2 glass for its lower cladding with a moderate peak power of 3000 W

BIOLOGICAL PROPERTIES AND MOLECULAR-GENETIC CHARACTERISTICS OF BACILLUS ANTHRACIS STRAINS, ISOLATED DURING THE OUTBREAK OF ANTHRAX IN THE YAMALO-NENETS AUTONOMOUS DISTRICT IN 2016

Objective of the study was to identify phenotypic properties and genetic peculiarities of Bacillus anthracis strains, isolated during the outbreak of anthrax in the territory of Yamal in 2016. Materials and methods. Investigated were the strains of anthrax agent, applying basic and subsequent identification tests and canSNP-, MLVA-genotyping methods and whole genome sequencing. Results and conclusions. The results showed the identity of the phenotypic properties, canSNPand MLVA25-genotypes, and profiles of whole genome-sequencing, regardless of the source of the strains isolation. Confirmed was a common source of human infection. Defined were phylogenetic interrelations of the tested strains and their position in global B. anthracis population. For the first time ever explored was variability of the gene pattern, associated with pathogenicity, and demonstrated – the efficiency of the proposed algorithm for genetic typing

Вариабельность митохондриального генома у больных раком молочной железы в популяции якуток

Background. The Sakha (Yakutia) population, the indigenous population of Siberia living in Yakutia, has one of the lowest rates of breast cancer (BC) incidence worldwide. The low BC incidence among the indigenous population of Yakutia has been reported by several authors, but to date the reasons for this phenomenon have not been fully elucidated. It should be noted that the study of factors that reduce the risk of BC is important for its prevention. In several studies, no hereditary BC was found in the Yakuts, and no pathogenic variants of the BRCA1/2 genes associated with hereditary syndromes of breast and ovarian cancers were found. In this regard, we decided to shift the focus to studying the mitochondrial genome of Sakha BC patients using the sequencing method.The purpose of the study was to identify BC-associated mitochondrial genome variants in Sakha patients.Material and Methods. The study included 14 Sakha patients diagnosed with BC. The median age of the patients was 49 years. DNA isolation was performed using phenol-chloroform extraction. DNA libraries were prepared using the Nextera Flex kit (Illumina, USA).Whole-genome sequencing of the mitochondrial genome was performed on a MiSeq instrument (Illuminа, USA). in the Shared Use Centre of the Research Institute of Medical Genetics, Tomsk National Research Centre of the Russian Academy of Sciences. The results obtained in BC patients were compared with those of control subjects.Results. In Sakha women with BC, 159 mitochondrial genome variants that differed from the human mitochondrial DNA (mtDNA) reference sequence (rCRS) were identified. Likely pathogenic variants m.3736G>A of the MT-ND1 gene and m.7279T>C of the MT-CO1 gene were shown to be associated with BC. For the first time, variants predisposing to BC (m.10398A>G; m.14783T>C; m.15043G>A; m.15301G>A) were identified. A distinctive feature of the mitochondrial genome of populations with a low BC incidence is a high level of mtDNA variants with changes in the length of the polycytosine region in the D310 locus.Conclusion. For the first time, mtDNA variants with changes in the length of the polycytosine tract in the D310 locus and likely pathogenic variants m.3736G>A of the MT-ND1 gene and m.7279T>C of the MT-CO1 gene were identified in Sakha BC women. The data obtained indicate that further studies on the role of the identified mtDNA variants in the development of BC using a larger sample of Sakha patients are required.Введение. Популяция саха (якуты) – коренное население Сибири, проживающее на территории Якутии, отличается одним из самых низких в мире уровнем заболеваемости раком молочной железы (РМЖ). Низкий уровень заболеваемости РМЖ коренного населения Якутии отмечен в ряде публикаций, но до настоящего времени причины этого явления не до конца выяснены. Следует отметить, что изучение факторов, снижающих риск заболевания РМЖ, имеет важное значение для его профилактики. По результатам ряда исследований, у якутов не обнаружено наследственных форм РМЖ, не найдено патогенных вариантов генов BRCA1/2, ассоциированных с наследственными синдромами РМЖ и рака яичника (РЯ). В связи с этим мы приняли решение сместить акцент на исследование митохондриального генома больных РМЖ саха методом секвенирования.Цель исследования – выявить варианты митохондриального генома, ассоциированные с РМЖ, у пациенток саха.Материал и методы. В исследование включено 14 пациенток саха с диагнозом РМЖ, средний возраст составил 49 лет. Выделение ДНК осуществляли методом фенол-хлороформной экстракции. ДНК-библиотеки готовили с помощью набора Nextera Flex (Illumina, США). Полногеномное секвенирование митохондриального генома выполнялось на приборе MiSeq (Illumina, США) на базе ЦКП Томского НИМЦ. Полученные результаты у больных РМЖ сравнивались с популяционным контролем.Результаты. У женщин саха, больных РМЖ, выявлено 159 вариантов митохондриального генома, отличающихся от референсной последовательностью митохондриальной ДНК (мтДНК) человека (rCRS). Показана ассоциация вероятно патогенных вариантов m.3736G>A гена МТ-ND1 и m.7279T>C гена MT-CO1 с РМЖ. Впервые выявлены варианты, предрасполагающие к РМЖ (m.10398A>G; m.14783T>C; m.15043G>A; m.15301G>A). Особенностью митохондриального генома популяций с низким уровнем заболеваемости РМЖ является высокий уровень вариантов мтДНК с изменением длины полицитозинового участка в локусе D310.Заключение. Впервые у женщин с РМЖ из популяции саха выявлены варианты мтДНК с изменением длины полицитозинового тракта в локусе D310 и вероятно патогенные варианты m.3736G>A гена МТ-ND1 и m.7279T>C гена MT-CO1. Полученные данные свидетельствуют о целесообразности дальнейшего изучения роли выявленных вариантов мтДНК в развитии РМЖ на расширенной выборке пациентов саха

The neurobiology of mouse models syntenic to human chromosome 15q

Autism is a neurodevelopmental disorder that manifests in childhood as social behavioral abnormalities, such as abnormal social interaction, impaired communication, and restricted interest or behavior. Of the known causes of autism, duplication of human chromosome 15q11–q13 is the most frequently associated cytogenetic abnormality. Chromosome 15q11–q13 is also known to include imprinting genes. In terms of neuroscience, it contains interesting genes such as Necdin, Ube3a, and a cluster of GABAA subunits as well as huge clusters of non-coding RNAs (small nucleolar RNAs, snoRNAs). Phenotypic analyses of mice genetically or chromosomally engineered for each gene or their clusters on a region of mouse chromosome seven syntenic to human 15q11–q13 indicate that this region may be involved in social behavior, serotonin metabolism, and weight control. Further studies using these models will provide important clues to the pathophysiology of autism. This review overviews phenotypes of mouse models of genes in 15q11–q13 and their relationships to autism

Use of multidimensional item response theory methods for dementia prevalence prediction: an example using the Health and Retirement Survey and the Aging, Demographics, and Memory Study.

BACKGROUND: Data sparsity is a major limitation to estimating national and global dementia burden. Surveys with full diagnostic evaluations of dementia prevalence are prohibitively resource-intensive in many settings. However, validation samples from nationally representative surveys allow for the development of algorithms for the prediction of dementia prevalence nationally. METHODS: Using cognitive testing data and data on functional limitations from Wave A (2001-2003) of the ADAMS study (n = 744) and the 2000 wave of the HRS study (n = 6358) we estimated a two-dimensional item response theory model to calculate cognition and function scores for all individuals over 70. Based on diagnostic information from the formal clinical adjudication in ADAMS, we fit a logistic regression model for the classification of dementia status using cognition and function scores and applied this algorithm to the full HRS sample to calculate dementia prevalence by age and sex. RESULTS: Our algorithm had a cross-validated predictive accuracy of 88% (86-90), and an area under the curve of 0.97 (0.97-0.98) in ADAMS. Prevalence was higher in females than males and increased over age, with a prevalence of 4% (3-4) in individuals 70-79, 11% (9-12) in individuals 80-89 years old, and 28% (22-35) in those 90 and older. CONCLUSIONS: Our model had similar or better accuracy as compared to previously reviewed algorithms for the prediction of dementia prevalence in HRS, while utilizing more flexible methods. These methods could be more easily generalized and utilized to estimate dementia prevalence in other national surveys

Mapping inequalities in exclusive breastfeeding in low- and middle-income countries, 2000–2018

Abstract: Exclusive breastfeeding (EBF)—giving infants only breast-milk for the first 6 months of life—is a component of optimal breastfeeding practices effective in preventing child morbidity and mortality. EBF practices are known to vary by population and comparable subnational estimates of prevalence and progress across low- and middle-income countries (LMICs) are required for planning policy and interventions. Here we present a geospatial analysis of EBF prevalence estimates from 2000 to 2018 across 94 LMICs mapped to policy-relevant administrative units (for example, districts), quantify subnational inequalities and their changes over time, and estimate probabilities of meeting the World Health Organization’s Global Nutrition Target (WHO GNT) of ≥70% EBF prevalence by 2030. While six LMICs are projected to meet the WHO GNT of ≥70% EBF prevalence at a national scale, only three are predicted to meet the target in all their district-level units by 2030