Active Data Replica Recovery for Quality-Assurance Big Data Analysis in IC-IoT

QoS-aware big data analysis is critical in Information-Centric Internet of Things (IC-IoT) system to support various applications like smart city, smart grid, smart health, intelligent transportation systems, and so on. The employment of non-volatile memory (NVM) in cloud or edge system provides good opportunity to improve quality of data analysis tasks. However, we have to face the data recovery problem led by NVM failure due to the limited write endurance. In this paper, we investigate the data recovery problem for QoS guarantee and system robustness, followed by proposing a rarity-aware data recovery algorithm. The core idea is to establish the rarity indicator to evaluate the replica distribution and service requirement comprehensively. With this idea, we give the lost replicas with distinguishing priority and eliminate the unnecessary replicas. Then, the data replicas are recovered stage by stage to guarantee QoS and provide system robustness. From our extensive experiments and simulations, it is shown that the proposed algorithm has significant performance improvement on QoS and robustness than the traditional direct data recovery method. Besides, the algorithm gives an acceptable data recovery time

The interaction between changes of muscle activation and cortical network dynamics during isometric elbow contraction: a sEMG and fNIRS study

Objective: The relationship between muscle activation during motor tasks and cerebral cortical activity remains poorly understood. The aim of this study was to investigate the correlation between brain network connectivity and the non-linear characteristics of muscle activation changes during different levels of isometric contractions.Methods: Twenty-one healthy subjects were recruited and were asked to perform isometric elbow contractions in both dominant and non-dominant sides. Blood oxygen concentrations in brain from functional Near-infrared Spectroscopy (fNIRS) and surface electromyography (sEMG) signals in the biceps brachii (BIC) and triceps brachii (TRI) muscles were recorded simultaneously and compared during 80% and 20% of maximum voluntary contraction (MVC). Functional connectivity, effective connectivity, and graph theory indicators were used to measure information interaction in brain activity during motor tasks. The non-linear characteristics of sEMG signals, fuzzy approximate entropy (fApEn), were used to evaluate the signal complexity changes in motor tasks. Pearson correlation analysis was used to examine the correlation between brain network characteristic values and sEMG parameters under different task conditions.Results: The effective connectivity between brain regions in motor tasks in dominant side was significantly higher than that in non-dominant side under different contractions (p < 0.05). The results of graph theory analysis showed that the clustering coefficient and node-local efficiency of the contralateral motor cortex were significantly varied under different contractions (p < 0.01). fApEn and co-contraction index (CCI) of sEMG under 80% MVC condition were significantly higher than that under 20% MVC condition (p < 0.05). There was a significant positive correlation between the fApEn and the blood oxygen value in the contralateral brain regions in both dominant or non-dominant sides (p < 0.001). The node-local efficiency of the contralateral motor cortex in the dominant side was positively correlated with the fApEn of the EMG signals (p < 0.05).Conclusion: In this study, the mapping relationship between brain network related indicators and non-linear characteristic of sEMG in different motor tasks was verified. These findings provide evidence for further exploration of the interaction between the brain activity and the execution of motor tasks, and the parameters might be useful in evaluation of rehabilitation intervention

Alteration and clinical potential in gut microbiota in patients with cerebral small vessel disease

BackgroundCerebral small vessel disease (CSVD) is a cluster of microvascular disorders with unclear pathological mechanisms. The microbiota-gut-brain axis is an essential regulatory mechanism between gut microbes and their host. Therefore, the compositional and functional gut microbiota alterations lead to cerebrovascular disease pathogenesis. The current study aims to determine the alteration and clinical value of the gut microbiota in CSVD patients.MethodsSixty-four CSVD patients and 18 matched healthy controls (HCs) were included in our study. All the participants underwent neuropsychological tests, and the multi-modal magnetic resonance imaging depicted the changes in brain structure and function. Plasma samples were collected, and the fecal samples were analyzed with 16S rRNA gene sequencing.ResultsBased on the alpha diversity analysis, the CSVD group had significantly decreased Shannon and enhanced Simpson compared to the HC group. At the genus level, there was a significant increase in the relative abundances of Parasutterella, Anaeroglobus, Megasphaera, Akkermansia, Collinsella, and Veillonella in the CSVD group. Moreover, these genera with significant differences in CSVD patients revealed significant correlations with cognitive assessments, plasma levels of the blood-brain barrier-/inflammation-related indexes, and structural/functional magnetic resonance imaging changes. Functional prediction demonstrated that lipoic acid metabolism was significantly higher in CSVD patients than HCs. Additionally, a composite biomarker depending on six gut microbiota at the genus level displayed an area under the curve of 0.834 to distinguish CSVD patients from HCs using the least absolute shrinkage and selection operator (LASSO) algorithm.ConclusionThe evident changes in gut microbiota composition in CSVD patients were correlated with clinical features and pathological changes of CSVD. Combining these gut microbiota using the LASSO algorithm helped identify CSVD accurately

Central nitric oxide regulation of the hypothalamic-pituitary-adrenocortical axis in adult male rats.

International audienceThe presence of nitric oxide (NO) synthase (NOS) in hypothalamic structures which control the activity of the pituitary-adrenocortical axis suggests that NO might be involved in the central regulation of ACTH secretion. We have studied the involvement of NO in the activity of the hypopothalamic-pituitary-adrenocortical (HPA) axis in intact and adrenalectomized rats. The acute effects (4 h) of two NOS inhibitors (HP-228 and NMMA), injected into the left lateral cerebral ventricle of freely moving male rats, on hypothalamic CRH and pituitary proopiomelacortin (POMC) mRNA levels as well as ACTH plasma levels were evaluated. In intact rats, HP-228, but not NMMA, induced an increase in CRH mRNA levels, while in adrenalectomized animals, both NOS inhibitors were effective in increasing CRH mRNA. In intact and adrenalectomized rats, both NOS inhibitors induced an increase in anterior pituitary POMC mRNA levels. Plasma ACTH levels were significantly elevated from 30 min to 2 h following the administration of either HP-228 or NMMA. In adrenalectomized animals, both NOS inhibitors produced a much striking increase of plasma ACTH levels which were still significantly increased at the longest time-interval studied. These results suggest that the central NO system exerts a tonic negative influence on the activity of the HPA axis in the presence or absence of circulating glucocorticoids

Dehydroepiandrosterone administration reverses the inhibitory influence of aging on gonadotrophin-releasing hormone gene expression in the male and female rat brain

International audienceDehydroepiandrosterone (DHEA) has been shown to exert a beneficial influence on some aging-associated deficits in rodents. It is well documented that in the rat, aging is associated with a decline in reproductive functions. In order to evaluate the effect of DHEA on GnRH gene expression in aged animals, we have studied the effect of 2.5-d administration of DHEA to young (50-54 d of age) and aged (18 mo of age) rats of both sexes. In the young males, DHEA induced an 18% reduction in the hybridization signal. In the aged animals, the mRNA levels were 10% lower than those observed in the young rats. DHEA completely restored the mRNA levels when compared to those detected in young male animals. In the young female, DHEA produced a 11% increase in GnRH mRNA, whereas, in the aged animals, hybridization signal was decreased by 28%. DHEA administration to aged females induced a 33% increase in the amount of mRNA, thus completely reversing the influence of aging. These results indicate that the decrease in GnRH gene expression which is likely involved in the loss of reproductive functions in aged rats can be totally reversed by a short term administration of DHEA which restored the GnRH neuronal activity. They also suggest that DHEA might play a role in the prevention and/or improvement of some deficits associated with aging through stimulation of GnRH biosynthesis

Prophylactic Use of Troxerutin Can Delay the Development of Diabetic Cognitive Dysfunction and Improve the Expression of Nrf2 in the Hippocampus on STZ Diabetic Rats

Background. With the change in lifestyle and the aging population, the incidence of cognitive dysfunction in diabetes mellitus is rising sharply. Oxidative stress is an important mechanism in the development of diabetic cognitive dysfunction. Nuclear factor E2-related factor 2 (Nrf2) is the core transcription factor of antioxidative stress. Early prevention and treatment of diabetic cognitive dysfunction can reduce the incidence of dementia and improve the quality of life of diabetic patients. Aim. This study was aimed at determining effect of troxerutin on the development of cognitive dysfunction and the expression level of Nrf2 in the hippocampus of streptozotocin (STZ) diabetic rats, when used in the early preventive stage. Methods. An STZ-induced diabetic rat model was established (n=30), and the animals were randomly divided into 2 groups: diabetic control group (DC, n=15) and diabetic troxerutin intervention group (DT, n=15). Another 10 normoglycemic rats were put into a normal control group (NC, n=10). While the DT group was injected with troxerutin (60 mg/kg), the DC group and the NC group were injected with physiological saline for 12 weeks daily. Learning and memory behaviors were tested using the Morris water maze test. The superoxide dismutase (SOD) activity, malondialdehyde (MDA) content, mRNA level, and protein level of Nrf2 were measured. Data were collected and analyzed by the statistical software package SPSS 19.0, which included one-way analysis of variance with completely randomized design. Results. Learning and memory levels were significantly improved in the DT group compared with the DC group. Moreover, in the DT group, the expression level of Nrf2 in the hippocampus was increased, activity of SOD was elevated, and MDA content was decreased. Conclusion. Prophylactic use of troxerutin delays the development of diabetic cognitive dysfunction and increases the expression level of Nrf2 in the hippocampus of STZ diabetic rats

Role of Glucocorticoids in the Modulation of Corticotropin-Releasing Hormone mRNA Level by the Endogenous Benzodiazepine Receptor Ligand Octadecaneuropeptide in Rat Brain

International audienceWe have recently demonstrated that the endozepine octadecaneuropeptide (ODN) exerts an inhibitory influence on corticotropin-releasing hormone (CRH) mRNA expression. The effect is mediated by GABAA receptors and is reversed by adrenalectomy. In order to investigate the involvement of peripheral steroids and more particularly of glucocorticoids in the ODN modulation of CRH mRNA expression, we have evaluated, in adrenalectomized and castrated male rats (ADX/CX), the effect of dexamethasone (DEX) pretreatment on CRH mRNA expression induced by central injection of ODN. Variations in the CRH mRNA expression in the hypothalamic paraventricular nucleus have been studied using quantitative in situ hybridization. The intracerebroventricular injection of ODN (4 microg/kg), as previously reported, induced a significant inhibition of CRH mRNA expression in sham-operated rats (-33%). This inhibition was reversed in ADX/CX male rats (+65% vs. sham vehicle-injected rats and +20% vs. ADX/CX vehicle-injected rats). Pretreatment with DEX (5 mg/kg) during 4 days induced in ADX/CX rats a decrease of 22% (vs. ADX/CX vehicle-injected rats) in the CRH mRNA signal, which became comparable to that observed in sham vehicle-injected rats. Pretreatment of ADX/CX animals with DEX prevented the ODN-induced increase in CRH mRNA expression, inducing rather a 16 and 30% inhibition when compared to vehicle- and ODN-injected ADX/CX rats, respectively. Moreover the CRH mRNA levels observed in ODN-injected ADC/CX rats were higher than those observed in sham vehicle- and sham ODN-injected rats (+16% vs. sham vehicle-injected rats and +63% vs. sham ODN-injected rats). These results indicate that dexamethasone treatment in ADX/CX rats can restore mRNA levels to those observed in sham-operated animals but not the inhibiting effect induced by ODN. Together with previous findings, these results suggest that adrenal and/or gonadal factor(s) other than glucocorticoids are involved in ODN modulation of the HPA axis