78 research outputs found

    Research progress on in-situ intelligent sorting and filling technology of coal gangue underground

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    Coal gangue needs to be transported to the ground for further treatment in traditional underground mines, which not only occupies land spaces, but also causes atmospheric and environmental pollutions due to spontaneous combustion and rainwater leaching. Moreover, energy consumption problems caused by long-distance ineffective transportation have become a key bottleneck restricting the low-carbon development of coal mines. In order to realize the underground disposal of coal gangue, and to reduce carbon emission and energy resource consumption per unit output from the source of coal production, as well as to realize the green low-carbon intelligent mining of coal, the present situation and intelligent progress of underground sorting and filling technology of coal gangue are comprehensively reviewed, and in this regard, the developing trend of underground sorting and filling technology of coal gangue is also anticipated. Meanwhile, an innovative method of underground in-situ green intelligent sorting and filling of coal gangue is proposed, and the structure and principle of coal gangue intelligent sorting and new filling hydraulic support are described in detail, so as to minimize the invalid transportation distance of gangue. In order to deal with the gangue of coal mining face and prevent the dynamic disaster of coal and rock, an intelligent integrated system of mining, sorting and filling in coal mine is designed, including four subsystems, i.e., an intelligent mining system with less gangue, an in-situ intelligent sorting system, a mine pressure inversion system of working face and a precise scientific filling system. Meanwhile, new logic relationships among multiple subsystems are discussed, so as to form a virtuous cycle of coal mining conducive to sorting, sorting conducive to filling and filling conducive to coal mining. In order to deal with the gangue in the heading face, an intelligent integrated system of underground excavation, aimed at sorting and filling in coal mine is proposed also with four subsystems, i.e., an intelligent fast excavation system, an intelligent sorting system, a coal gangue transportation system and an intelligent filling system, and the work and intelligent realization of each subsystem are described. The proposed new process in this study is expected to realize the underground disposal of coal gangue, and provide new ideas for the research of in-situ intelligent sorting and filling method of coal gangue and the integrated system of mining, sorting and filling

    Determination of beam incidence conditions based on the analysis of laser interference patterns

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    Beam incidence conditions in the formation of two-, three- and four-beam laser interference patterns are presented and studied in this paper. In a laser interference lithography (LIL) process, it is of importance to determine and control beam incidence conditions based on the analysis of laser interference patterns for system calibration as any slight change of incident angles or intensities of beams will introduce significant variations of periods and contrasts of interference patterns. In this work, interference patterns were captured by a He-Ne laser interference system under different incidence conditions, the pattern period measurement was achieved by cross-correlation with, and the pattern contrast was calculated by image processing. Subsequently, the incident angles and intensities of beams were determined based on the analysis of spatial distributions of interfering beams. As a consequence, the relationship between the beam incidence conditions and interference patterns is revealed. The proposed method is useful for the calibration of LIL processes and for reverse engineering applications

    Post-stroke cognitive impairment: exploring molecular mechanisms and omics biomarkers for early identification and intervention

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    Post-stroke cognitive impairment (PSCI) is a major stroke consequence that has a severe impact on patients’ quality of life and survival rate. For this reason, it is especially crucial to identify and intervene early in high-risk groups during the acute phase of stroke. Currently, there are no reliable and efficient techniques for the early diagnosis, appropriate evaluation, or prognostication of PSCI. Instead, plenty of biomarkers in stroke patients have progressively been linked to cognitive impairment in recent years. High-throughput omics techniques that generate large amounts of data and process it to a high quality have been used to screen and identify biomarkers of PSCI in order to investigate the molecular mechanisms of the disease. These techniques include metabolomics, which explores dynamic changes in the organism, gut microbiomics, which studies host–microbe interactions, genomics, which elucidates deeper disease mechanisms, transcriptomics and proteomics, which describe gene expression and regulation. We looked through electronic databases like PubMed, the Cochrane Library, Embase, Web of Science, and common databases for each omics to find biomarkers that might be connected to the pathophysiology of PSCI. As all, we found 34 studies: 14 in the field of metabolomics, 5 in the field of gut microbiomics, 5 in the field of genomics, 4 in the field of transcriptomics, and 7 in the field of proteomics. We discovered that neuroinflammation, oxidative stress, and atherosclerosis may be the primary causes of PSCI development, and that metabolomics may play a role in the molecular mechanisms of PSCI. In this study, we summarized the existing issues across omics technologies and discuss the latest discoveries of PSCI biomarkers in the context of omics, with the goal of investigating the molecular causes of post-stroke cognitive impairment. We also discuss the potential therapeutic utility of omics platforms for PSCI mechanisms, diagnosis, and intervention in order to promote the area’s advancement towards precision PSCI treatment

    Microglia Mediate Synaptic Material Clearance at the Early Stage of Rats With Retinitis Pigmentosa

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    Resident microglia are the main immune cells in the retina and play a key role in the pathogenesis of retinitis pigmentosa (RP). Many previous studies on the roles of microglia mainly focused on the neurotoxicity or neuroprotection of photoreceptors, while their contributions to synaptic remodeling of neuronal circuits in the retina of early RP remained unclarified. In the present study, we used Royal College of Surgeons (RCS) rats, a classic RP model characterized by progressive microglia activation and synapse loss, to investigate the constitutive effects of microglia on the synaptic lesions and ectopic neuritogenesis. Rod degeneration resulted in synapse disruption and loss in the outer plexiform layer (OPL) at the early stage of RP. Coincidentally, the resident microglia in the OPL increased phagocytosis and mainly engaged in phagocytic engulfment of postsynaptic mGluR6 of rod bipolar cells (RBCs). Complement pathway might be involved in clearance of postsynaptic elements of RBCs by microglia. We pharmacologically deleted microglia using a CSF1 receptor (CSF1R) inhibitor to confirm this finding, and found that it caused the accumulation of postsynaptic mGluR6 levels and increased the number and length of ectopic dendrites in the RBCs. Interestingly, the numbers of presynaptic sites expressing CtBP2 and colocalized puncta in the OPL of RCS rats were not affected by microglia elimination. However, sustained microglial depletion led to progressive functional deterioration in the retinal responses to light in RCS rats. Based on our results, microglia mediated the remodeling of RBCs by phagocytosing postsynaptic materials and inhibiting ectopic neuritogenesis, contributing to delay the deterioration of vision at the early stage of RP

    Varying the ratio of Lys: Met through enhancing methionine supplementation improved milk secretion ability through regulating the mRNA expression in bovine mammary epithelial cells under heat stress

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    IntroductionThe ratio of lysine (Lys) to methionine (Met) with 3.0: 1 is confirmed as the “ideal” profile for milk protein synthesis, but whether this ratio is suitable for milk protein synthesis under HS needs to be further studied.MethodsTo evaluate the molecular mechanism by which HS and Lys to Met ratios affect mammary cell functional capacity, an immortalized bovine mammary epithelial cell line (MAC-T) is incubated with 5 doses of Met while maintaining a constant concentration of Lys. The MAC-T cells was treated for 6 h as follow: Lys: Met 3.0: 1 (control 37°C and IPAA 42°C) or treatments under HS (42°C) with different ratios of Lys: Met at 2.0: 1 (LM20), 2.5: 1 (LM25), 3.5: 1 (LM35) and 4.0: 1 (LM40). RNA sequencing was used to assess transcriptome-wide alterations in mRNA abundance.ResultsThe significant difference between control and other groups was observed base on PCA analysis. A total of 2048 differentially expressed genes (DEGs) were identified in the IPAA group relative to the control group. Similarly, 226, 306, 148, 157 DEGs were detected in the LM20, LM25, LM35 and LM40 groups, respectively, relative to the IPAA group. The relative mRNA abundance of HSPA1A was upregulated and anti-apoptotic genes (BCL2L1 and BCL2) was down-regulated in the IPAA group, compared to the control group (p < 0.05). Compared with the IPAA group, the relative mRNA abundance of anti-apoptotic genes and casein genes (CSN1S2 and CSN2) was up-regulated in the LM25 group (p < 0.05). The DEGs between LM25 and IPAA groups were associated with the negative regulation of transcription RNA polymerase II promoter in response to stress (GO: 0051085, DEGs of BAG3, DNAJB1, HSPA1A) as well as the mTOR signaling pathway (ko04150, DEGs of ATP6V1C2, WNT11, WNT3A, and WNT9A). Several DEGs involved in amino acids metabolism (AFMID, HYKK, NOS3, RIMKLB) and glycolysis/gluconeogenesis (AFMID and MGAT5B) were up-regulated while DEGs involved in lipolysis and beta-oxidation catabolic processes (ALOX12 and ALOX12B) were down-regulated.ConclusionThese results suggested that increasing Met supply (Lys: Met at 2.5: 1) may help mammary gland cells resist HS-induced cell damage, while possibly maintaining lactation capacity through regulation of gene expression

    Microstructural Characteristics and Mechanical Properties of Friction Stir Spot Welded 2A12-T4 Aluminum Alloy

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    2A12-T4 aluminum alloy was friction stir spot welded, and the microstructural characteristics and mechanical properties of the joints were investigated. A softened microstructural region existed in the joint, and it consisted of stir zone (SZ), thermal mechanically affected zone (TMAZ), and heat affected zone (HAZ). The minimum hardness was located in TMAZ, and the average hardness value in SZ can be improved by appropriately increasing welding heat input. The area of complete bonding region at the interface increased with increasing welding heat input because more interface metals were mixed. In a certain range of FSSW parameters, the tensile shear failure load of the joint increased with increasing rotation speed, but it decreased with increasing plunge rate or decreasing shoulder plunging depth. Two kinds of failure modes, that is, shear fracture mode and tensile-shear mixed fracture mode, can be observed in the tensile shear tests, and the joint that failed in the tensile-shear mixed fracture mode possessed a high carrying capability

    Disease progression patterns and risk factors associated with mortality in deceased patients with COVID‐19 in Hubei Province, China

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    Background: Detailed descriptions of the patterns of disease progression of deceased coronavirus disease 2019 (COVID-19) patients have not been well explored. Objectives: This study sought to explore disease progression patterns and risk factors associated with mortality of deceased patients with COVID-19. Materials and Methods: Epidemiological, clinical, laboratory, and imaging data (from 15 January to 26 March 2020) of laboratory-confirmed COVID-19 patients were collected retrospectively from two hospitals, Hubei province, China. Disease progression patterns of patients were analyzed based on laboratory data, radiological findings, and Sequential Organ Failure Assessment (SOFA) score. Risk factors associated with death were analyzed. Results: A total of 792 patients were enrolled in this study, of whom 68 died and 724 survived. Complications during hospitalization, such as sepsis, severe acute respiratory distress syndrome, acute cardiac injury, and acute kidney injury, were markedly more frequent in deceased patients than in surviving patients. Deceased patients presented progressive deterioration pattern in laboratory variables, chest computed tomography evaluation, and SOFA score, while surviving patients presented initial deterioration to peak level involvement followed by improvement pattern over time. Days 10 to 14 after illness onset was a critical stage of disease course. Older age, number of preexisting comorbidities ≥2, and SOFA score were independently associated with death for COVID-19. Conclusions: Multiorgan dysfunction was common in deceased COVID-19 patients. Deceased patients presented progressive deterioration pattern, while surviving patients presented a relatively stable pattern during disease progression. Older age, number of preexisting comorbidities ≥2, and SOFA score were independent risk factors for death for COVID-19
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