Sex-specific signatures of intrinsic hippocampal networks and regional integrity underlying cognitive status in multiple sclerosis

The hippocampus is an anatomically compartmentalized structure embedded in highly wired networks that are essential for cognitive functions. The hippocampal vulnerability has been postulated in acute and chronic neuroinflammation in multiple sclerosis, while the patterns of occurring inflammation, neurodegeneration or compensation have not yet been described. Besides focal damage to hippocampal tissue, network disruption is an important contributor to cognitive decline in multiple sclerosis patients. We postulate sex-specific trajectories in hippocampal network reorganization and regional integrity and address their relationship to markers of neuroinflammation, cognitive/memory performance and clinical severity. In a large cohort of multiple sclerosis patients (n = 476; 337 females, age 35 ± 10 years, disease duration 16 ± 14 months) and healthy subjects (n = 110, 54 females; age 34 ± 15 years), we utilized MRI at baseline and at 2-year follow-up to quantify regional hippocampal volumetry and reconstruct single-subject hippocampal networks. Through graph analytical tools we assessed the clustered topology of the hippocampal networks. Mixed-effects analyses served to model sex-based differences in hippocampal network and subfield integrity between multiple sclerosis patients and healthy subjects at both time points and longitudinally. Afterwards, hippocampal network and subfield integrity were related to clinical and radiological variables in dependency of sex attribution. We found a more clustered network architecture in both female and male patients compared to their healthy counterparts. At both time points, female patients displayed a more clustered network topology in comparison to male patients. Over time, multiple sclerosis patients developed an even more clustered network architecture, though with a greater magnitude in females. We detected reduced regional volumes in most of the addressed hippocampal subfields in both female and male patients compared to healthy subjects. Compared to male patients, females displayed lower volumes of para- and presubiculum but higher volumes of the molecular layer. Longitudinally, volumetric alterations were more pronounced in female patients, which showed a more extensive regional tissue loss. Despite a comparable cognitive/memory performance between female and male patients over the follow-up period, we identified a strong interrelation between hippocampal network properties and cognitive/memory performance only in female patients. Our findings evidence a more clustered hippocampal network topology in female patients with a more extensive subfield volume loss over time. A stronger relation between cognitive/memory performance and the network topology in female patients suggests greater entrainment of the brain's reserve. These results may serve to adapt sex-targeted neuropsychological interventions

Проект пункта шиномонтажного участка с конструктивной разработкой устройства для измерения биений шин и ободьев колес в условиях ИП Русанова

В разделе объект и методы исследования выполнен аналитический обзор по теме работы и обоснован выбор темы выпускной работы бакалавра. В разделе расчеты и аналитика представлены необходимые инженерные расчеты, связанные с организацией работ по разработке шиномонтажного участка с конструктивной разработкой устройства для измерения биений шин и ободьев колёс.In the object and research methods section, an analytical review is carried out on the topic of work and the choice of the theme of the final work of the bachelor is substantiated. The section of calculations and analytics presents the necessary engineering calculations related to the organization of work on the development of the tire section with the constructive development of a device for measuring the runout of tires and wheel rims

Влияние исходного состава углеродных пресс - композиций на внутреннюю и внешнюю поверхность получаемых из них таблеток

Исследование влияния наличия в исходных для прессования углеродных смесях связующих веществ, их свойств и количества, на размеры внутренней и внешней поверхности получающихся из них таблеток.Investigation of the effect of the presence of binders in the initial compression mixtures of carbon mixtures, their properties and quantities, on the dimensions of the inner and outer surfaces of the tablets obtained from them

Повышение конкурентоспособности предприятия как фактор экономического роста промышленности России на примере нефтяного комплекса

Объектом исследования является: конкурентоспособность АО "Сибирская Сервисная Компания". Предметом исследования являются: факторы и условия конкурентоспособности предприятия, влияющие на экономический рост промышленности. Цель работы – разработка мероприятий по повышению конкурентоспособности АО "Сибирская Сервисная Компания". В результате исследования: разработаны мероприятия по повышению конкурентоспособности АО "Сибирская Сервисная Компания". Практическое значение: на основе оценки эндогенных и экзогенных факторов разработаны сводные мероприятия, дана оценка эффективности от внедрения организационных и технико–технологических мероприятий по повышению конкурентоспособности предприятия.The object of study is: the competitiveness of JSC "Siberian Service Company". The subject of the study are: factors and conditions of enterprise competitiveness, affecting the economic growth of industry. The purpose of the work is the development of measures to increase the competitiveness of Siberian Service Company JSC. As a result of the study: measures were developed to increase the competitiveness of Siberian Service Company JSC. Practical value: based on the assessment of endogenous and exogenous factors, summary measures have been developed, an assessment of the effectiveness of the introduction of organizational, technical and technological measures to increase the competitiveness of the enterprise has been given

The genetic architecture of the human cerebral cortex

The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder

Assessment of Myocardial Edema by Computed Tomography in Myocardial Infarction

ObjectivesThe aim of this study was to analyze whether cardiac computed tomography (CT) permits the assessment of myocardial edema in acute myocardial infarction (MI).BackgroundSeveral studies proved the value of detecting myocardial edema from T2-weighted cardiac magnetic resonance (CMR) for differentiating acute from chronic MI. Computed tomography is suited for depicting MI, but there are no data on CT imaging of myocardial edema. We hypothesized that areas of reduced attenuation in acute MI may correspond to edema.MethodsIn 7 pigs (55.2 ± 7.3 kg), acute MI was induced using a closed chest model. Animals underwent unenhanced arterial and late-phase dual source computed tomography (DSCT) followed by T2-weighted and delayed contrast-enhanced CMR. Animals were sacrificed, and the excised hearts were stained with 2,3,5-triphenyltetrazolin chloride (TTC). Size of MI, contrast-to-noise ratio, and percent signal difference were compared among the different imaging techniques with concordance-correlation coefficients (ρc), Bland-Altman plots, and analysis of variance for repeated measures.ResultsInfarction was transmural on all slices. On unenhanced, arterial, and late-phase DSCT, mean sizes of MI were 27.2 ± 8.5%, 20.1 ± 6.9%, and 23.1 ± 8.2%, respectively. Corresponding values on T2-weighted and delayed enhanced CMR were 28.5 ± 7.8% and 22.2 ± 7.7%. Size of MI on TTC staining was 22.6 ± 7.8%. Best agreement was observed when comparing late-phase CT (ρc = 0.9356) and delayed enhanced CMR (ρc = 0.9248) with TTC staining. There was substantial agreement between unenhanced DSCT and T2-weighted CMR (ρc = 0.8629). Unenhanced DSCT presented with the lowest percent signal difference (46.0 ± 18.3) and the lowest contrast-to-noise ratio (4.7 ± 2.0) between infarcted and healthy myocardium.ConclusionsUnenhanced DSCT permits the detection of myocardial edema in large acute MI. Further studies including smaller MI in different coronary artery territories and techniques for improving the contrast-to-noise ratio are needed

Correction: Positive Contrast MRI Techniques for Visualization of Iron-Loaded Hernia Mesh Implants in Patients

OBJECT:In MRI, implants and devices can be delineated via susceptibility artefacts. To discriminate susceptibility voids from proton-free structures, different positive contrast techniques were implemented. The purpose of this study was to evaluate a pulse sequence-based positive contrast technique (PCSI) and a post-processing susceptibility gradient mapping algorithm (SGM) for visualization of iron loaded mesh implants in patients. MATERIAL AND METHODS:Five patients with iron-loaded MR-visible inguinal hernia mesh implants were examined at 1.5 Tesla. A gradient echo sequence (GRE; parameters: TR: 8.3ms; TE: 4.3ms; NSA:2; FA:20°; FOV:350mm²) and a PCSI sequence (parameters: TR: 25ms; TE: 4.6ms; NSA:4; FA:20°; FOV:350mm²) with on-resonant proton suppression were performed. SGM maps were calculated using two algorithms. Image quality and mesh delineation were independently evaluated by three radiologists. RESULTS:On GRE, the iron-loaded meshes generated distinct susceptibility-induced signal voids. PCSI exhibited susceptibility differences including the meshes as hyperintense signals. SGM exhibited susceptibility differences with positive contrast. Visually, the different algorithms presented no significant differences. Overall, the diagnostic value was rated best in GRE whereas PCSI and SGM were barely "sufficient". CONCLUSION:Both "positive contrast" techniques depicted implanted meshes with hyperintense signal. SGM comes without additional acquisition time and can therefore be utilized in every patient