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Stroke seriously affects human health. Many studies have shown that enriched environment (EE) can promote functional recovery after stroke, but the intrinsic mechanisms remain unclear. In order to study the internal mechanisms of EE involved in functional recovery after ischemic stroke and which mechanism plays a leading role in the recovery of limb function after cerebral infarction, key proteins potentially involved in neuronal protection and synaptic remodeling in the ischemic penumbra have been investigated. In this study, adult C57BL/6 mice after permanent middle cerebral artery occlusion (pMCAO) were assigned to the EE and standard housing (SH) groups 3 days after operation. The EE house was spacious that contained a large variety of small toys; the SH was a normal sized cage. Sham-operated mice without artery occlusion were housed under standard conditions and were fed a normal diet. On days 3, 7, 14, and 21, postoperative motor functional recovery was tested using the modified neurological severity score (mNSS) and the Rotarod test. The expression of B-cell lymphoma-2 (Bcl-2), Bcl-2-associated X protein (Bax), growth-associated protein-43 (GAP-43), and synaptophysin (SYN) was examined by western blotting and immunofluorescence staining. The motor functional recovery (based on the mNSS and Rotarod test 3, 7, 14, and 21 days post operation) of mice in the EE group improved significantly compared to the SH group. The expression of GAP-43 and SYN and the ratio of Bcl-2/Bax were all upregulated in the EE group compared to the SH group. In addition, we also explored the relationship between neuronal protection and synaptic remodeling in the EE-mediated recovery of limb function after cerebral infarction by correlation analysis. Correlation analysis showed that compared with the increase of Bcl-2/Bax ratio, the increased expression of GAP-43 and SYN was more closely related to the recovery of limb function in ischemic mice. These data support the hypothesis that EE can promote the process of improvement of limb dysfunction induced by ischemic stroke, and this behavior restoration may, via promoting neuroprotection in the ischemic penumbra, be dependent on the regulation of the expression of GAP-43, SYN, Bcl-2, and Bax. A limitation of the study was that we only observed several representative key indicators of synaptic remodeling and neuronal apoptosis, without an in-depth study of the potential mechanisms involved.

Soil microbes play essential roles in the biogeochemical processes of organic carbon and nutrient cycling. Many studies have reported various short-term effects of fertilization on soil microbes. However, less is known about the effects of longterm fertilization regimes on the rhizosphere. Therefore, the objective of this study was to explore how the soil microbial communities in the rhizosphere respond to different long-term fertilization strategies. Based on a 21-year field treatment experiment in Guizhou, China, we extracted phospholipid fatty acids (PLFAs) to determine the microbial community structure in both the non-rhizosphere (NR) and rhizosphere (R). Six treatments were included: no fertilizer (CK), mineral nitrogen fertilizer (N), N with potassium (NK), phosphorus with K (PK), NPK, and NPK combined with manure (MNPK). The results showed that total PLFAs under unbalanced mineral fertilization (N, NK and PK) were decreased by 45% on average in the NR compared with CK, whereas MNPK increased fungi and G– bacteria abundance significantly in both the NR (by 33 and 23%) and R (by 15 and 20%), respectively. In addition, all microbial groups in the R under these treatments (N, NK and PK) were significantly increased relative to those in the NR, except for the ratio of F/B and G+/G–, which might be due to the high nutrient availability in the R. Soil pH and SOC significantly regulated the soil microbial community and structure, explaining 51 and 20% of the variation in the NR, respectively. However, the rhizosphere microbial community structure was only significantly affected by soil pH (31%). We concluded that the soil microbial community in the NR was more strongly affected by long-term fertilization than that in the R due to the rhizosphere effect in the agricultural ecosystem. Rhizosphere nutrient conditions and buffering capacity could help microbial communities resist the change from the long-term fertilization.

Many studies have shown that fibronectin type III domain-containing protein 5 (FDNC5) and brain-derived neurotrophic factor (BDNF) play vital roles in plasticity after brain injury. An enriched environment refers to an environment that provides animals with multi-sensory stimulation and movement opportunities. An enriched environment has been shown to promote the regeneration of nerve cells, synapses, and blood vessels in the animal brain after cerebral ischemia; however, the exact mechanisms have not been clarified. This study aimed to determine whether an enriched environment could improve neurobehavioral functions after the experimental inducement of cerebral ischemia and whether neurobehavioral outcomes were associated with the expression of FDNC5 and BDNF. This study established ischemic mouse models using permanent middle cerebral artery occlusion (pMCAO) on the left side. On postoperative day 1, the mice were randomly assigned to either enriched environment or standard housing condition groups. Mice in the standard housing condition group were housed and fed under standard conditions. Mice in the enriched environment group were housed in a large cage, containing various toys, and fed with a standard diet. Sham-operated mice received the same procedure, but without artery occlusion, and were housed and fed under standard conditions. On postoperative days 7 and 14, a beam-walking test was used to assess coordination, balance, and spatial learning. On postoperative days 16-20, a Morris water maze test was used to assess spatial learning and memory. On postoperative day 15, the expression levels of FDNC5 and BDNF proteins in the ipsilateral cerebral cortex were analyzed by western blot assay. The results showed that compared with the standard housing condition group, the motor balance and coordination functions (based on beam-walking test scores 7 and 14 days after operation), spatial learning abilities (based on the spatial learning scores from the Morris water maze test 16-19 days after operation), and memory abilities (based on the memory scores of the Morris water maze test 20 days after operation) of the enriched environment group improved significantly. In addition, the expression levels of FDNC5 and BDNF proteins in the ipsilateral cerebral cortex increased in the enriched environment group compared with those in the standard housing condition group. Furthermore, the Pearson correlation coefficient showed that neurobehavioral functions were positively associated with the expression levels of FDNC5 and BDNF (r = 0.587 and r = 0.840, respectively). These findings suggest that an enriched environment upregulates FDNC5 protein expression in the ipsilateral cerebral cortex after cerebral ischemia, which then activates BDNF protein expression, improving neurological function. BDNF protein expression was positively correlated with improved neurological function. The experimental protocols were approved by the Institutional Animal Care and Use Committee of Fudan University, China (approval Nos. 20160858A232, 20160860A234) on February 24, 2016.

The level of cerebellar activity in stroke patients has been shown to correlate with the extent of functional recovery. We reasoned that the cerebellum may be an important player in post-stroke rehabilitation. Because the neurons in the deep cerebellar nuclei (DCN) represent virtually all of the output from the cerebellum, in this study, using environmental enrichment (EE) to promote rehabilitation, we investigated the influence of the optogenetic neuronal modulation of DCN on EE-induced rehabilitation. We found that neuronal inhibition of the DCN almost completely blocked motor recovery in EE treated mice, but the stroke mice with neuronal activation of the DCN achieved a similar recovery level as those in the EE treated group. No difference was observed in anxiety-like behavior. Moreover, Htr2a in the DCN, the gene encoding 5-HT2A receptor, was shown to be a hub gene in the protein-protein interaction network identified using RNA-seq. This indicated that 5-HT2A receptor-mediated signaling may be responsible for DCN-dependent functional improvement in EE. We further verified this using the 5-HT2A receptor antagonist, MDL100907, to inhibit the function of 5-HT2A receptor in the DCN. This treatment resulted in impaired recovery in EE treated mice, who performed at a level as poor as the stroke-only group. Thus, this work contributes to an understanding of the importance of the DCN activation in EE-induced post-stroke rehabilitation. Attempts to clarify the mechanism of 5-HT2A receptor-mediated signaling in the DCN may also lead to the creation of a pharmacological mimetic of the benefits of EE-induced rehabilitation.

Poststroke cognitive impairment severely affects the long-term recovery of patients. However, it remains unknown whether an enriched environment can remodel contralateral hippocampal function and promote cognitive function recovery after cerebral ischemic injury. To further explore, 36 C57BL/6 mice that underwent permanent middle cerebral artery occlusion (pMCAO) were randomly assigned to three groups: enriched environment (EE), standard condition (SC), and sham surgery (Sham). After 21 days of intervention, the Morris water maze and step-through test was utilized for testing the cognitive function of the mice, cresyl violet staining for measuring the degree of atrophy in the hippocampal tissues, and western blotting for quantitating the expression levels of GA1B, GAD67, and NR2B, and immunohistochemistry for levels of NR2B in the CA1 region of the contralateral hippocampus. The results showed that cognitive function-related behavioral performance decreased in the SC group, and performance was better in the EE group than that in the SC group ( p p > 0.05); levels of GA1B, GAD67, and NR2B in the contralateral hippocampus were significantly higher in the EE group than those in the SC group ( p p

Fertilization affects soil microbial community by altering soil organic carbon (C) and nutrients availability. However, it remains unclear how changes in stoichiometric C, N, and P ratios resulting from fertilization affect microbial community. We investigated a 26-year field experiment receiving inorganic fertilizers (N, NP, PK, and NPK), organic N combination (with manure and straw), natural recovery (fallow), and no fertilizer (control). The aim of this study was to explore the responses of microbial community to C: N:P stoichiometry in soil and microbial biomass of topsoil (0–20 cm) and subsoil (20–40 cm). Results showed that compared to control treatment, organic application increased the ratio of fungi to bacteria (F:B) in topsoil and gram-negative bacteria to gram-positive bacteria (G−:G+) in subsoil. However, application of inorganic decreased both the F: B and G−:G+ ratio in topsoil. Increasing soil C, N and P availability resulted from inorganic fertilizers and organic combination fertilization caused stoichiometric imbalance between soil and microbial biomass. As a result, the F:B and G−:G+ ratio were positively related to C:N imbalance but negatively associated with N:P imbalance in topsoil. Redundancy analysis (RDA) showed that main factors regulating microbial community were pH, C:P and N:P imbalances in topsoil, whereas TDN, N:P imbalance, DOC and soil C:N in subsoil. Furthermore, C:P and N:P imbalance explained 16.4% in topsoil, and N:P imbalance explained 22.0% in subsoil of microbial community variation. These results reveal the shifts of soil microbial community are driven by changes in soil pH and C, N and P stoichiometric imbalance from long-term fertilization.

An enriched environment (EE) can stimulate the recovery of neurological function following a cerebral ischaemia-reperfusion injury; however, the impact of EE's on mitochondrial function has been insufficiently studied. Our research aimed to assess whether EE's therapeutic impact involved the enhancement of mitochondrial dysfunction. Following 2 weeks of EE training, we tested both mitochondrial function and mitochondria-associated protein expression within the cerebral cortex following cerebral ischaemia-reperfusion injury. We subjected Sprague-Dawley rats to transient focal cerebral ischaemia and categorized the rats into three separate groups, i.e. an enriched environment (EE) group, a standard condition (SC) group and a sham control group (no middle cerebral artery embolization). The rats within the EE group were raised in enriched conditions for 2 weeks, while the rats within the SC group, in comparison, were reared in standard conditions for 2 weeks. After 2 weeks, the cerebral cortices of the rats were removed. We then measured a series of indices, i.e. the protein expression of peroxisome proliferator-activated receptor gamma coactivator (PGC-1α), nuclear respiratory factor-1 (NRF-1), mitochondrial transcription factor A (TFAM) and mitochondrial protein cytochrome C oxidase subunit IV (COX IV). Furthermore, the number of mitochondria was evaluated through electron microscopy.EE upregulated the protein expression of PGC-1α, NRF-1 as well as TFAM, which function as the master regulators of mitochondrial biogenesis, in comparison with the SC group. The EE group's COX IV protein expression also exhibited an increase. Moreover, the amount of mitochondria in the peri-infarct region of the cortex increased as result of EE training. Over 2 weeks, EE training significantly increased mitochondrial biogenesis-associated protein expression and mitochondrial function. A possible mechanism of the EE leading to the improvement of neurological function is that it increases brain mitochondrial biogenesis after the rats' cerebral ischaemia-reperfusion injury. Mitochondrial biogenesis stimulation or enhancement could become an innovative strategy for neuroprotection in future treatment.

Currently, no specific treatment exists to promote recovery from cognitive impairment after a stroke. Dysfunction of the actin cytoskeleton correlates well with poststroke cognitive declines, and its reorganization requires proper regulation of Rho-associated kinase (ROCK) proteins. Fasudil downregulates ROCK activation and protects neurons against cytoskeleton collapse in the acute phase after stroke. An enriched environment can reduce poststroke cognitive impairment. However, the efficacy of environmental enrichment combined with fasudil treatment remains poorly understood. A photothrombotic stroke model was established in 6-week-old male C57BL/6 mice. Twenty-four hours after modeling, these animals were intraperitoneally administered fasudil (10 mg/kg) once daily for 14 successive days and/or provided with environmental enrichment for 21 successive days. After exposure to environmental enrichment combined with fasudil treatment, the number of neurons in the hippocampal CA1 region increased significantly, the expression and proportion of p-cofilin in the hippocampus decreased, and the distribution of F-actin in the hippocampal CA1 region increased significantly. Furthermore, the performance of mouse stroke models in the tail suspension test and step-through passive avoidance test improved significantly. These findings suggest that environmental enrichment combined with fasudil treatment can ameliorate memory dysfunction through inhibition of the hippocampal ROCK/cofilin pathway, alteration of the dynamic distribution of F-actin, and inhibition of neuronal death in the hippocampal CA1 region. The efficacy of environmental enrichment combined with fasudil treatment was superior to that of fasudil treatment alone. This study was approved by the Animal Ethics Committee of Fudan University of China (approval No. 2019-Huashan Hospital JS-139) on February 20, 2019.

In this work, a simple, rapid, and low-cost sputtering system was used to deposit Ag-Au composite nanoparticles (CNPs) onto an indium titanium oxide (ITO) anode for polymer light-emitting diodes (PLEDs) at room temperature. These Ag-Au CNPs on ITO surface serve as the resonators of electrons to result in a broader absorption under the visible light irradiation. The interlayer does not act as electron blocking layer, but hole injection enhancement by electron injection does seem to occur. Because of the localized surface plasmon resonance emission, the luminance efficiencies of the blue-, green-, and red-emitting PLEDs with Ag-Au CNPs increased by approximately 1.5-fold, compared to those of the reference devices. This method provided with the production of chemically stable Ag-Au CNPs under ambient conditions is well suited for enhancing the emission of large-area PLEDs in full color.

In this study, the micro tribological behavior of Cu50Zr50 amorphous alloy foils was investigated experimentally at room temperature by pin-on-disc tribological tests. It is found that the friction coefficients are mainly located between 0.15 and 0.45, and increase with the rotational sliding velocity. With the increase of rotational sliding velocity, the wear weight loss also increases. At lower rotational sliding velocity, the wear mechanism tends to a combination action of continuous wear and surface flow. At higher rotational sliding velocity, the wear mechanism tends to a continuous wear. The reported results provide a basis understanding of the tribological behavior of Cu50Zr50 amorphous alloys in micro scale.

H.264/AVC standard has been widely used in video compression at various kinds of application domain. Motion estimation takes the most calculation workload of H.264/AVC encoder. Memory optimization has played an even more important role in encoder design. Firstly, dependency relation between motion vectors was analyzed and removed at a little cost of estimation accuracy decrement, and then a 3-stage macro-block level pipeline architecture was proposed to increase parallel process ability of motion estimation. Then an optimized memory organization strategy of reference frame data was put forward, aiming at avoiding row changing frequently in SDRAM access. Finally, based on the 3-stage pipeline structure, a shared cyclic search window memory was proposed: 1) data relativity between adjacent macro-block was analyzed, 2) and search window memory size was elaborated, 3) and then a slice based structure and the work process were discussed. Analysis and experiment result show that 50% of on chip memory resource and cycles for off chip SDRAM access can be saved. The whole design was implemented with Verilog HDL and integrated into a H.264 encoder, which can demo 1280*720@30 video successfully at frequency of 120MHz under a cyclone III FPGA development board.

Molecular dynamic (MD) method is used to study the coalescence and fusing process of Au and Cu nanoclusters. The results show that shear deformation, surface and interface diffusion play important role in different stages of all simulation procedure. In most cases, shear deformation produces the twin boundary or/and stacking fault in particles by particle rotation and slide. The angle between the {111} of Au and Cu particles decrease with increasing temperature, which promotes the formation of the stable interface. Furthermore, the coalescence point and melting temperature increase as cluster diameter increases. For the other cases, there are no particle rotation and slide phenomenon in the elevating temperature process because the stable interface can be formed by forming twin boundaries once two particles contact.

This paper presents an open architecture CNC system for wire-EDM. The main part of the system is integrated combination of a real-time operating system running on a digital signal processor (DSP) board and a Window-based environment running on a PC. The hardware system consists of a master PC, DSP-based control card, an input-output interface card and a network card. The software system consists of operation, machine logic control, motion, machining process control, interpreter, man machine interface and communication. The proposed CNC system is featured with open architecture human machine interface, flexibility, modularity and Internet connectivity. The original CNC system has been superseded in a commercial wire-EDM machine by the developed CNC system. Experimental results verified the usefulness of the developed CNC system in manufacturing automation.

After searching for literature about the specificity of acupoints from China National Knowledge Infrastructure (CNKI) database (in Chinese) and MEDLINE (in English), published by Chinese scholars from June 2003 to June 2012, the authors made a systemic analysis on the retrieved papers. It was found that most Chinese scholars took a positive viewpoint about the specificity of acupoints in morphological structure, biophysical characters, pathological reactions, acupuncture stimulation-induced responses in different brain regions and therapeutic effects. However, the research methods and comprehensive analysis of abundant research results need being improved, and the conclusion should be validated extensively. Moreover, the research on the affecting factors of specificity of acupoints will be one of the major directions.