10 research outputs found

    Повышение эффективности нефтяных скважин в условиях коррозионной агрессивности скважинной продукции

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    Объектом исследования является ингибиторы коррозии и насосно-компрессорные трубы. Цель работы – провести глубокий анализ ингибиторов коррозии технологии подачи их в скважину и глубокий анализ насосно-компрессорные труб. Определить оптимальную дозировку реагента и оптимальный тип насосно-компрессорных труб для данных условий. В процессе исследования изучались негативные влияния коррозии на работу глубинно-насосного оборудование, рассматривались наиболее популярные технологии подачи ингибитора в скважину, а также проведён углубленный анализ ингибитор… Область применения: разработаны рекомендации для достижения наилучших показателей МРП и СНО.Object of a research is inhibitors of corrosion and pump and compressor pipes. The work purpose – to carry out the deep analysis of inhibitors of corrosion of technology of giving them to the well and the deep analysis pump and compressor pipes. To define an optimum dosage of reagent and optimum type of pump and compressor pipes for these conditions. In the course of the research negative impacts of corrosion on work deep and pump the equipment were studied, the most popular technologies of supply of inhibitor to the well were considered and also the profound analysis inhibitor is carried out … Scope: recommendations for achievement of the best indicators of MRP and SNO are developed

    Increase in admission rates and symptom severity of childhood and adolescent anorexia nervosa in Europe during the COVID-19 pandemic: data from specialized eating disorder units in different European countries

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    Background: The COVID-19 pandemic, associated with confinement and social isolation, seems to have impacted the course of many mental disorders in children and adolescents. An increase in hospital admission rates for juvenile anorexia nervosa (AN) has been documented in many regions of the world. However, data from Europe are scarce. Methods: We asked clinicians in specialized eating disorder units in hospitals of maximum care in France, Germany, Italy, Spain, Sweden, and the Netherlands to report on (i) overall (inpatient and outpatient) and (ii) inpatient admission rates for adolescents with AN during 2019 and 2020. Additionally, a modified version of the COVID Isolation Eating Scale (CIES) was used to assess the child and adolescent psychiatrists' estimations of a possible increase in symptom severity in children and adolescents with AN during the COVID-19 pandemic and to (iii) inquire about the contributing factors perceived by the caring professionals. Results: Four out of six representatives of European hospitals described a higher rate of overall admissions during the pandemic. Three hospitals out of six reported an increase in inpatient admissions, and two centres had constant high numbers of admissions of both outpatients and inpatients. The clinicians perceived a higher symptom severity in 2020 than in 2019, especially involving more frequent use of social media, longer duration of exercising, and more restrictive eating. They supposed an increase in social media consumption, a perceived 'loss of control', and a lack of in-person assessments and weight controls as the main contributing factors for the deterioration in AN numbers and symptomatology. Conclusions: The COVID-19 pandemic seems to have had a deep impact on symptom severity in AN, which is mirrored by a large increase in admission rates across Europe. An increase in exercise, social media consumption, a perceived 'loss of control', and a lack of face-to-face health care seem to have contributed to this development. Further investigation is required to identify which factors may lead to the increase in incidence and deterioration of childhood and adolescent AN. Possible preventive means for the future could include educating paediatricians and health care workers about AN, regular weight assessment, and home-based treatments

    Psychological impact of the COVID-19 pandemic on children with and without mental disorders

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    BackgroundPrevious and current studies highlight the psychological distress caused by COVID-19-associated restrictions among the general population, especially among children and adolescents; however, few studies have examined children and adolescents with a mental disorder. The current study aims to explore whether youth with mental disorders show a higher pandemic-associated psychological burden than healthy children and adolescents and to determine which psychiatric diagnoses are particularly associated with a higher distress level.Methods144 children and adolescents between the ages of 6 – 18 years with a mental disorder and 48 children and adolescents within the same age range without a mental disorder, and their caregivers, completed questionnaires assessing pandemic-associated trauma symptoms (the Child Report of Post-Traumatic Symptoms (CROPS) and the Parents Report of Post-Traumatic Symptoms (PROPS)). Additionally, we asked specific questions about pandemic-associated stress factors, such as financial problems, prolonged screen times or loneliness.ResultsChildren and adolescents with a mental illness showed a significantly higher psychological burden than mentally healthy peers. Female gender was a risk factor for a higher self-reported psychological burden, and a younger age was associated with a more extensive parent-reported psychological burden. Patients with a depressive disorder showed significantly higher levels of psychological distress associated with the COVID-19 pandemic than patients with an attention-deficit and/or a conduct disorder.ConclusionsChildren and adolescents with a mental illness, particularly females and individuals with a depressive disorder, are at an increased risk of suffering from pandemic-associated psychological distress. Adequate mental health care options, such as telepsychiatry, are indispensable

    Revisiting the Roco G-protein cycle

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    Mutations in leucine-rich-repeat kinase 2 (LRRK2) are the most frequent cause of late-onset Parkinson's disease (PD). LRRK2 belongs to the Roco family of proteins which share a conserved Ras-like G-domain (Roc) and a C-terminal of Roc (COR) domain tandem. The nucleotide state of small G-proteins is strictly controlled by guanine-nucleotide-exchange factors (GEFs) and GTPase-activating proteins (GAPs). Because of contradictory structural and biochemical data, the regulatory mechanism of the LRRK2 Roc G-domain and the RocCOR tandem is still under debate. In the present study, we solved the first nucleotide-bound Roc structure and used LRRK2 and bacterial Roco proteins to characterize the RocCOR function in more detail. Nucleotide binding induces a drastic structural change in the Roc/COR domain interface, a region strongly implicated in patients with an LRRK2 mutation. Our data confirm previous assumptions that the C-terminal subdomain of COR functions as a dimerization device. We show that the dimer formation is independent of nucleotide. The affinity for GDP/GTP is in the micromolar range, the result of which is high dissociation rates in the s(-1) range. Thus Roco proteins are unlikely to need GEFs to achieve activation. Monomeric LRRK2 and Roco G-domains have a similar low GTPase activity to small G-proteins. We show that GTPase activity in bacterial Roco is stimulated by the nucleotide-dependent dimerization of the G-domain within the complex. We thus propose that the Roco proteins do not require GAPs to stimulate GTP hydrolysis but stimulate each other by one monomer completing the catalytic machinery of the other

    Genome-wide analysis of rare copy number variations reveals PARK2 as a candidate gene for attention-deficit/hyperactivity disorder

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    Attention-deficit/hyperactivity disorder (ADHD) is a common, highly heritable neurodevelopmental disorder. Genetic loci have not yet been identified by genome-wide association studies. Rare copy number variations (CNVs), such as chromosomal deletions or duplications, have been implicated in ADHD and other neurodevelopmental disorders. To identify rare (frequency 1%) CNVs that increase the risk of ADHD, we performed a whole-genome CNV analysis based on 489 young ADHD patients and 1285 adult population-based controls and identified one significantly associated CNV region. In tests for a global burden of large (>500 kb) rare CNVs, we observed a nonsignificant (P=0.271) 1.126-fold enriched rate of subjects carrying at least one such CNV in the group of ADHD cases. Locus-specific tests of association were used to assess if there were more rare CNVs in cases compared with controls. Detected CNVs, which were significantly enriched in the ADHD group, were validated by quantitative (q)PCR. Findings were replicated in an independent sample of 386 young patients with ADHD and 781 young population-based healthy controls. We identified rare CNVs within the parkinson protein 2 gene (PARK2) with a significantly higher prevalence in ADHD patients than in controls (P=2.8 × 10(-4) after empirical correction for genome-wide testing). In total, the PARK2 locus (chr 6: 162 659 756-162 767 019) harboured three deletions and nine duplications in the ADHD patients and two deletions and two duplications in the controls. By qPCR analysis, we validated 11 of the 12 CNVs in ADHD patients (P=1.2 × 10(-3) after empirical correction for genome-wide testing). In the replication sample, CNVs at the PARK2 locus were found in four additional ADHD patients and one additional control (P=4.3 × 10(-2)). Our results suggest that copy number variants at the PARK2 locus contribute to the genetic susceptibility of ADHD. Mutations and CNVs in PARK2 are known to be associated with Parkinson disease

    Genome-wide association study in German patients with attention deficit/hyperactivity disorder

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    The heritability of attention deficit hyperactivity disorder (ADHD) is approximately 0.8. Despite several larger scale attempts, genome-wide association studies (GWAS) have not led to the identification of significant results. We performed a GWAS based on 495 German young patients with ADHD (according to DSM-IV criteria; Human660W-Quadv1; Illumina, San Diego, CA) and on 1,300 population-based adult controls (HumanHap550v3; Illumina). Some genes neighboring the single nucleotide polymorphisms (SNPs) with the lowest P-values (best P-value: 8.38 × 10(-7)) have potential relevance for ADHD (e.g., glutamate receptor, metabotropic 5 gene, GRM5). After quality control, the 30 independent SNPs with the lowest P-values (P-values ≤ 7.57 × 10(-5) ) were chosen for confirmation. Genotyping of these SNPs in up to 320 independent German families comprising at least one child with ADHD revealed directionally consistent effect-size point estimates for 19 (10 not consistent) of the SNPs. In silico analyses of the 30 SNPs in the largest meta-analysis so far (2,064 trios, 896 cases, and 2,455 controls) revealed directionally consistent effect-size point estimates for 16 SNPs (11 not consistent). None of the combined analyses revealed a genome-wide significant result. SNPs in previously described autosomal candidate genes did not show significantly lower P-values compared to SNPs within random sets of genes of the same size. We did not find genome-wide significant results in a GWAS of German children with ADHD compared to controls. The second best SNP is located in an intron of GRM5, a gene located within a recently described region with an infrequent copy number variation in patients with ADHD
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