83 research outputs found

    The influence of physiological aging and atrophy on brain viscoelastic properties in humans

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    Physiological aging of the brain is accompanied by ubiquitous degeneration of neurons and oligodendrocytes. An alteration of the cellular matrix of an organ impacts its macroscopic viscoelastic properties which can be detected by magnetic resonance elastography (MRE)--to date the only method for measuring brain mechanical parameters without intervention. However, the wave patterns detected by MRE are affected by atrophic changes in brain geometry occurring in an individual's life span. Moreover, regional variability in MRE-detected age effects is expected corresponding to the regional variation in atrophy. Therefore, the sensitivity of brain MRE to brain volume and aging was investigated in 66 healthy volunteers aged 18-72. A linear decline in whole-brain elasticity was observed (-0.75%/year, R-square = 0.59, p<0.001); the rate is three times that determined by volume measurements (-0.23%/year, R-square = 0.4, p<0.001). The highest decline in elasticity (-0.92%/year, R-square = 0.43, p<0.001) was observed in a region of interest placed in the frontal lobe with minimal age-related shrinkage (-0.1%, R-square = 0.06, p = 0.043). Our results suggest that cerebral MRE can measure geometry-independent viscoelastic parameters related to intrinsic tissue structure and altered by age

    Performance Evaluation - Annual Report Year 3

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    This report describes the work done and results obtained in third year of the CATNETS project. Experiments carried out with the different configurations of the prototype are reported and simulation results are evaluated with the CATNETS metrics framework. The applicability of the Catallactic approach as market model for service and resource allocation in application layer networks is assessed based on the results and experience gained both from the prototype development and simulations. --Grid Computing

    Risk factors for chronic postsurgical pain in visceral surgery: a matched case-control analysis.

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    PURPOSE Chronic postsurgical pain (CPSP) after abdominal visceral surgery is an underestimated long-term complication with relevant impact on health-related quality of life and socioeconomic costs. Early identification of affected patients is important. We aim to identify the incidence and risk factors for CPSP in this patient population. METHODS Retrospective case-control matched analysis including all patients diagnosed with CPSP after visceral surgery in our institution between 2016 and 2019. One-to-two case-control matching was based on operation category (HPB, upper-GI, colorectal, transplantation, bariatric, hernia and others) and date of surgery. Potential risk factors for CPSP were identified using conditional multivariate logistic regression. RESULTS Among a cohort of 3730 patients, 176 (4.7%) were diagnosed with CPSP during the study period and matched to a sample of 352 control patients. Independent risk factors for CPSP were age under 55 years (OR 2.64, CI 1.51-4.61), preexisting chronic pain of any origin (OR 3.42, CI 1.75-6.67), previous abdominal surgery (OR 1.99, CI 1.11-3.57), acute postoperative pain (OR 1.29, CI 1.16-1.44), postoperative use of non-steroidal anti-inflammatory drugs (OR 3.73, OR 1.61-8.65), opioid use on discharge (OR 3.78, CI 2.10-6.80) and length of stay over 3 days (OR 2.60, CI 1.22-5.53). Preoperative Pregabalin intake was protective (OR 0.02, CI 0.002-0.21). CONCLUSION The incidence of CPSP is high and associated with specific risk factors, some of them modifiable. Special attention should be given to sufficient treatment of preexisting chronic pain and acute postoperative pain

    Performance evaluation - annual report year 3

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    This report describes the work done and results obtained in third year of the CATNETS project. Experiments carried out with the different configurations of the prototype are reported and simulation results are evaluated with the CATNETS metrics framework. The applicability of the Catallactic approach as market model for service and resource allocation in application layer networks is assessed based on the results and experience gained both from the prototype development and simulations

    Guilt is effectively induced by a written auto-biographical essay but not reduced by experimental pain.

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    Introduction The aim of the present study was (1) to validate the method of guilt-induction by means of a written auto-biographical essay and (2) to test whether experimental pain is apt to alleviate the mental burden of guilt, a concept receiving support from both empirical research and clinical observation. Methods Three independent groups of healthy male participants were recruited. Group allocation was not randomized but within group pain/sham administration was counterbalanced over the two test-days. Groups were tested in the following consecutive order: Group A: guilt induction, heat-pain/sham, N = 59; Group B: guilt induction, cold-pressure-pain/sham, N = 43; Group C: emotionally neutral induction, heat-pain/sham, N = 39. Guilt was induced on both test-days in group A and B before pain/sham administration. Visual analog scale (VAS) guilt ratings immediately after pain/sham stimulation served as the primary outcome. In a control group C the identical heat-pain experiment was performed like in group A but a neutral emotional state was induced. Results A consistently strong overall effect of guilt-induction (heat-pain: p < 0.001, effect size r = 0.71; CPT-pain p < 0.001, r = 0.67) was found when compared to the control-condition (p = 0.25, r = 0.08). As expected, heat- and cold-pressure-stimuli were highly painful in all groups (p < 0.0001, r = 0.89). However, previous research supporting the hypothesis that pain is apt to reduce guilt was not replicated. Conclusion Although guilt-induction was highly effective on both test-days no impact of pain on behavioral guilt-ratings in healthy individuals could be identified. Guilt induction per se did not depend on the order of testing. The result questions previous experimental work on the impact of pain on moral emotions

    Электроснабжение установки перекачки нефти п. Пионерный ОАО «Томскнефть»

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    РЕФЕРАТ Выпускная квалификационная работа 149 с., 23 рис., 32 табл., 29 источников, 6 прил. Ключевые слова: нефтепровод, насос, электрооборудование, схема электроснабжения, линия, сеть, электроприемник, нагрузка, оборудование, защита, ток, напряжение, мощность. Объектом исследования является электрическая часть УПН п. Пионерный ОАО «Томскенефть». Цель работы – проектирование схемы электроснабжения предприятия, выбор оборудования. В процессе исследования проводился сбор исходных данных в ходе производственной практики на объекте исследования. В результате была спроектирована схема электроснабжения от подстанции энергосистемы, до конечного электроприемника. Были выбраны кабели и провода, коммутационное оборудование, были сделаны необходимые проверки. Также результатом работы сталESSAY Final qualifying work 149 p., 23 fig., 32 tab., 29 sources, 6 adj. Keywords: oil, pump, electrical equipment, power supply circuit, line, network, power-consuming equipment, load equipment, protection, current, voltage, power. The object of research is the electrical part of UPN claim. Pionerny of "Tomskeneft". The purpose of work - designing enterprise power scheme, the choice of equipment. The study was conducted to collect baseline data in the course of practical training on the subject of the study. As a result, power supply circuit has been designed from the substation grid, appliance, to the end. Were selected cables and wires, switching equipment, the necessary checks have been made. It is also the result of the work became an economic calculation of capital costs for the con

    Characterizing Acupuncture Stimuli Using Brain Imaging with fMRI - A Systematic Review and Meta-Analysis of the Literature

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    Background The mechanisms of action underlying acupuncture, including acupuncture point specificity, are not well understood. In the previous decade, an increasing number of studies have applied fMRI to investigate brain response to acupuncture stimulation. Our aim was to provide a systematic overview of acupuncture fMRI research considering the following aspects: 1) differences between verum and sham acupuncture, 2) differences due to various methods of acupuncture manipulation, 3) differences between patients and healthy volunteers, 4) differences between different acupuncture points. Methodology/Principal Findings We systematically searched English, Chinese, Korean and Japanese databases for literature published from the earliest available up until September 2009, without any language restrictions. We included all studies using fMRI to investigate the effect of acupuncture on the human brain (at least one group that received needle-based acupuncture). 779 papers were identified, 149 met the inclusion criteria for the descriptive analysis, and 34 were eligible for the meta-analyses. From a descriptive perspective, multiple studies reported that acupuncture modulates activity within specific brain areas, including somatosensory cortices, limbic system, basal ganglia, brain stem, and cerebellum. Meta-analyses for verum acupuncture stimuli confirmed brain activity within many of the regions mentioned above. Differences between verum and sham acupuncture were noted in brain response in middle cingulate, while some heterogeneity was noted for other regions depending on how such meta-analyses were performed, such as sensorimotor cortices, limbic regions, and cerebellum. Conclusions Brain response to acupuncture stimuli encompasses a broad network of regions consistent with not just somatosensory, but also affective and cognitive processing. While the results were heterogeneous, from a descriptive perspective most studies suggest that acupuncture can modulate the activity within specific brain areas, and the evidence based on meta-analyses confirmed some of these results. More high quality studies with more transparent methodology are needed to improve the consistency amongst different studies
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