characteristic change
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Author(s):  
Н.С. Бахтигараев

Представлены особенности изменения параметров движения геосинхронного объекта 10294 SIRIO-1 №1977-080A по результатам оптических наблюдений в обсерваториях в Звенигороде, на пике Терскол и на горе Санглох республики Таджикистан. Пассивный итальянский научный космический аппарат SIRIO-1 представляет интерес тем, что он описывает классическую восьмерку вокруг точки либрации 75 ◦ в.д. без дрейфа по долготе и всегда доступен наблюдениям с наших пунктов. Это дает возможность детально исследовать поступательно-вращательное движение объекта, используя только результаты своих измерений. SIRIO-1 наблюдался нами для проверки аппаратуры и программного обеспечения как тестовый объект с очень устойчивой орбитой. В 2018 г. у этого объекта были обнаружены изменения в движении и в кривых блеска, не свойственные космическому мусору. Были зафиксированы небольшое скачкообразное изменение орбиты между 7 и 11 марта 2018 г. и изменение коэффициента отношения площади миделевого сечения объекта к его массе; кроме того перестал надежно определяться период изменения блеска и появилось характерное изменение блеска на одном и том же участке траектории с периодом, примерно равным звездным суткам. The features of changes in the motion parameters of the geosynchronous object 10294 SIRIO-1 No.1977-080A based on the results of optical observations at the observatories in Zvenigorod, Terskol Peak and Sanglokh Mountain in the Republic of Tajikistan are presented. The passive Italian scientific spacecraft SIRIO-1 is of interest to us because it describes the classic eight around the libration point of 75 ◦ E without longitude drift and is always available to observations from our observation points. This makes it possible to study in detail the translational-rotational motion of the object, using only the results of their measurements. SIRIO-1 was observed by us to test the hardware and software as a test object with a very stable orbit. In 2018, this object was found to have changes in motion and in the light curves that are not characteristic to space debris. A small abrupt change in the orbit between March 7 and 11, 2018, and a change in the area-to-mass ratio of the object were recorded. In addition, the period of change in the brightness was no longer reliably determined, and a characteristic change in the brightness appeared on the same part of the trajectory with a period approximately equal to the sidereal day.


2021 ◽  
Vol 2021 ◽  
pp. 1-19
Author(s):  
Zhenhong Guo ◽  
Xiaoyue Sun ◽  
Juhong Yang ◽  
Jinlan Xie ◽  
Feifei Zhong ◽  
...  

Aims. We investigated the changes of retinal structure in normal glucose tolerance (NGT), impaired glucose tolerance (IGT), diabetes mellitus (DM), and diabetic kidney disease (DKD) stages in Otsuka Long-Evans Tokushima Fatty (OLETF) rats. Methods. We assigned OLETF rats to four groups based on their OGTT results and 24 h urinary microalbumin (24 h UMA) levels: NGT, IGT, DM, and DKD groups. We observed the structural and the corresponding pathological changes and quantified the expression of HIF-1α, iNOS, NF-κB, VEGF, ICAM-1, and occludin in the retina. Results. Significant damage to the retinal structure, especially in retinal ganglion cells (RGCs), was observed in the IGT stage. The expression of HIF-1α, iNOS, NF-κB, VEGF, and ICAM-1 was significantly upregulated, while that of occludin was downregulated. Conclusion. Significant retinal neuropathy occurs in the IGT stage. Inflammation and hypoxia may damage the blood retina barrier (BRB), leading to diabetic retinopathy.


2021 ◽  
Author(s):  
Weina Yao ◽  
Xiao Zhang ◽  
Hui Zhao ◽  
Yun Xu ◽  
Feng Bai

Abstract Backgroud: Plasma neurofilament light chain (NFL) is a potential biomarker for neurodegenerative diseases. Both NFL and the interactions of core subsystem and frontoparietal network (FPN) are associated with the cognitive integrity. The present study was to investigate the underlying mechanism and application of plasmaNFL couplingcore-FPN in Alzheimer’s disease (AD). Methods: A total of 224 AD-spectrum participants with complete resting-state fMRI, neuropsychological tests and plasma NFL at baseline (n=112) and after approximately 17 months follow up (n=112) . Brain networks construction of core subsystem and FPN wereperformed in these subjects. The follow-up data were used to test and verify these baseline characteristics. Furthermore, Receiver Operating Characteristic analysiswas used to explore the classification by the association of plasma NFL and core-FPN, and the mediation analysis were appliedto investigate the significance of plasma NFL coupling networks on cognitive impairments in these subjects. Results: The discernment ofdisease-relatedinteractions of core subsystem and FPN maybe the neural network fundamentals of plasmaNFL regarding to cognitive decline in AD-spectrum patients. Furthermore, the clinical significance of plasma NFL coupling networks on AD identification and monitoring cognitive impairments were observed in these subjects. Conclusions: The characteristic change of plasma NFL coupling networks could expect to be used as an potential indicator of future targeted therapies and prevention strategies in AD patients.


2021 ◽  
pp. 507-512
Author(s):  
Koichi Sugioka ◽  
Kiyoshi Yamamura ◽  
Yutaka Yamamoto ◽  
Yasuhiro Sanuki

2021 ◽  
Vol 10 (11) ◽  
pp. 2412
Author(s):  
Weronika Wasyluk ◽  
Agnieszka Zwolak

Sepsis is defined as “life-threatening organ dysfunction caused by a dysregulated host response to infection”. Contrary to the older definitions, the current one not only focuses on inflammation, but points to systemic disturbances in homeostasis, including metabolism. Sepsis leads to sepsis-induced dysfunction and mitochondrial damage, which is suggested as a major cause of cell metabolism disorders in these patients. The changes affect the metabolism of all macronutrients. The metabolism of all macronutrients is altered. A characteristic change in carbohydrate metabolism is the intensification of glycolysis, which in combination with the failure of entering pyruvate to the tricarboxylic acid cycle increases the formation of lactate. Sepsis also affects lipid metabolism—lipolysis in adipose tissue is upregulated, which leads to an increase in the level of fatty acids and triglycerides in the blood. At the same time, their use is disturbed, which may result in the accumulation of lipids and their toxic metabolites. Changes in the metabolism of ketone bodies and amino acids have also been described. Metabolic disorders in sepsis are an important area of research, both for their potential role as a target for future therapies (metabolic resuscitation) and for optimizing the current treatment, such as clinical nutrition.


Author(s):  
Dong-shin Ko ◽  
Hyun-ju Lee ◽  
Deog-jae Hur

Noise generation for helping people recognize the driving status of vehicles at low speeds has become legalized with the spread of electric and hydrogen vehicles, which requires a virtual engine sound generator. Furthermore, these generators require a slim design for installation in the vehicle. Therefore, in this study, in order to examine the relationship between the design parameters of the horizontal magnetized structure for maintaining the electromagnetic force performance and minimizing the actuator thickness, an independent analysis using a single variable and an investigation of the characteristic change due to multiple variables were sequentially performed. With respect to factor analysis of multiple variables, a screening analysis for performance improvement factors and an impact analysis for effects were conducted using a full factorial design. To verify the nonlinear characteristics, the significance of the curvature effect was verified by adding a central point to the analytical points of view, and a nonlinear regression model of the prediction model was derived using the face-centered central composite design of the response surface methodology. Five design parameters were found to influence the electromagnetic force performance and thickness minimization in the horizontal magnetized structure: magnet thickness, magnet adapter thickness, plate thickness, yoke position, and yoke thickness. Furthermore, when the tolerance management level of the design in the manufacturing process of each design parameter was limited to 3σ, the confidence level was predicted to increase to the range of 98.69–99.73% for the electromagnetic force performance and to the range of 97.64–99.73% for thickness minimization


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Ryosuke Tokida ◽  
Masashi Uehara ◽  
Masaki Nakano ◽  
Takako Suzuki ◽  
Noriko Sakai ◽  
...  

AbstractThe aim of this study was to provide definitive reference values for bone mineral density (BMD) and bone turnover markers in the general elderly population. Registered citizens of 50 to 89 years old were targeted for this survey. After random sampling from the resident registry of Obuse town, we established eight groups based on age (50 s, 60 s, 70 s, and 80 s) and gender. A total of 411 people were enrolled. We used a dual-energy x-ray absorptiometry device to measure and evaluate BMD. The bone formation marker bone alkaline phosphatase (BAP) was measured as a bone turnover marker. Bone quality marker pentosidine, and bone resorption markers including urinary total deoxypyridinoline (DPD), tartrate-resistant acid phosphatase 5b (TRACP-5b), 25-hydroxyvitamin D (25[OH]D), and whole parathyroid hormone (PTH) were also measured as bone turnover markers. Sixty-three people (15.3%) were diagnosed as osteoporosis. BMD decreased with age in the femoral neck and total hip. On the other hand, there was no characteristic change with age in the lumber spine. As for bone markers, pentosidine and DPD increased with aging, although 25(OH)D, whole PTH, and BAP showed no characteristic associations with gender and aging. In terms of the relationship between low BMD and bone markers, there was a significant independent association between low BMD and TRACP-5b in females. In conclusions, hip BMD decreased with aging in men and women. However, there was no characteristic decline with aging in the lumbar spine. All bone markers showed no significant independent characteristics associated with age or gender in a multivariate analysis model, except for a significant association between low BMD and TRACP-5b in females. TRACP-5b was a potentially useful marker for the detection of low BMD.


PLoS ONE ◽  
2021 ◽  
Vol 16 (2) ◽  
pp. e0246464
Author(s):  
Artur Sokolovsky ◽  
Thomas Gross ◽  
Jaume Bacardit

Topic Detection and Tracking (TDT) is a very active research question within the area of text mining, generally applied to news feeds and Twitter datasets, where topics and events are detected. The notion of “event” is broad, but typically it applies to occurrences that can be detected from a single post or a message. Little attention has been drawn to what we call “micro-events”, which, due to their nature, cannot be detected from a single piece of textual information. The study investigates the feasibility of micro-event detection on textual data using a sample of messages from the Stack Overflow Q&A platform and Free/Libre Open Source Software (FLOSS) version releases from Libraries.io dataset. We build pipelines for detection of micro-events using three different estimators whose parameters are optimized using a grid search approach. We consider two feature spaces: LDA topic modeling with sentiment analysis, and hSBM topics with sentiment analysis. The feature spaces are optimized using the recursive feature elimination with cross validation (RFECV) strategy. In our experiments we investigate whether there is a characteristic change in the topics distribution or sentiment features before or after micro-events take place and we thoroughly evaluate the capacity of each variant of our analysis pipeline to detect micro-events. Additionally, we perform a detailed statistical analysis of the models, including influential cases, variance inflation factors, validation of the linearity assumption, pseudo R2 measures and no-information rate. Finally, in order to study limits of micro-event detection, we design a method for generating micro-event synthetic datasets with similar properties to the real-world data, and use them to identify the micro-event detectability threshold for each of the evaluated classifiers.


Author(s):  
Z. Huang ◽  
H.-Y. Lai ◽  
H.-B. Zhou ◽  
H. Guo

Process of horizontal twin roll casting magnesium alloy was analyzed by numerical simulation. Taking solidification welding line in cast rolling area as research object, the characteristic change of solidification welding line caused by casting rolling temperature, casting rolling speed and roll heat transfer capacity and its influence on the forming process of casting rolling area were analyzed. The results show that increasing casting temperature, casting speed or reducing heat transfer capacity of roll can make solidification welding line shift to exit of casting rolling zone. Increasing casting temperature and casting speed will increase difference between middle and edge of the solidification welding line along casting direction. And heat distribution of whole slab is more uniform. However, effect of improving heat transfer capacity of roll is completely opposite. According to this, optimum process parameters of casting and rolling magnesium alloy with plate thickness of 6 mm are put forward to reduce probability of edge crack.


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