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Cooling techniques following thermal treatments and related microcracking are a hot spot in rock mechanics and must be precisely studied. Hence, this research performed systematic experiments on the influences of rapid cooling on the behavior of thermally treated granodiorite at different temperatures. Furthermore, using the optical microscope, a comparison between rapid and slow cooling methods was studied to investigate how the cooling process affected the microstructure of the Egyptian granodiorite. The granodiorite samples were heated to 200, 400, 600, and 800 °C and then cooled slowly by air and rapidly by the water. According to the experimental results, the changes in examined properties occurred in three distinct temperature stages: zone I (25–200 °C), zone II (200–400 °C), and zone III (400–800 °C). Zone II was a conspicuous transition region for the rapid cooling approach, distinguished by a significant increase in porosity, thermal damage, crack density, and a substantial decrease in wave velocities, uniaxial compressive strength, and elastic modulus. Microcrack densities and widths increased with temperature for both cooling methods. According to microscopic analyses of granodiorite samples, boundary cracks were formed at the boundaries of quartz and feldspar first due to their minimal lattice energy, followed by biotite of high lattice energy. However, due to the thermal shock induced, the intragranular microcracks of the rapid cooling technique began to form at lower temperatures (200 °C). The physical and mechanical properties of rapidly cooled granodiorite significantly dropped between 200 and 400 °C, and the failure mode altered from axial splitting to shear modes. Consequently, over 600 °C, longitudinal waves could not penetrate rock samples due to the thermal fusion of inter and transgranular fissures, which turned into macrocracks. Hence, the elastic modulus measurements and wave velocity at 800 °C were challenging with an extremely low UCS and complex failure mode. [ABSTRACT FROM AUTHOR]

Phosphine‐catalyzed chemodivergent reactions of para‐quinone methides (p‐QMs) affording a wide variety of diarylmethyl thioether derivatives have been reported. In the transformation presented in this work, P(4‐FC6H4)3 catalyzed the direct 1,6‐addition of p‐QMs with thiols, whereas P(4‐MeC6H4)3 promoted the tandem addition/self‐aldol condensation reactions of p‐QMs with 1,4‐dithiane‐2,5‐diol. Moreover, some of the obtained products were screened against cancer cell lines HepG2, NB4, and K562, and one was found to inhibit the proliferation of all the tested cancer cell types. [ABSTRACT FROM AUTHOR]

Mineral transformations often induce microstructural deteriorations during temperature variations. Hence, it is crucial to understand why and how this microstructure weakens due to mineral alteration with temperature and the correlated physical and mechanical responses. Therefore, in this study, physical, chemical, thermal, petrographic, and mechanical analyses were carried out to comprehend better the thermal behaviors of Egyptian granodiorite exposed to temperatures as high as 800 °C. The experimental results indicate that the examined attributes change in three distinct temperature phases. Strength zone (up to 200 °C): During this phase, the temperature only slightly impacts the granodiorite mass loss and porosity, and the P-wave velocity and E slightly decrease. However, the rock structure was densified, which resulted in a minor increase in strength. After that, the transition zone (200–400 °C) was distinguished by the stability of most studied parameters. For instance, mass and porosity did not significantly alter, and the uniaxial compressive strength steadily increased with an axial failure mode. When the temperature rises, transgranular cracks cause the P-wave velocity and elastic modulus to decrease moderately. The decay zone started after 400 °C and continued to 800 °C. This zone is characterized by complicated factors that worsen the granodiorite properties, lead to color shift, and produce a shear failure mode. The properties of granodiorite became worse because of chemical reactions, structural and crystal water evaporation, rising thermal expansion coefficient variation, and quartz inversion at 575 °C (α to β, according to the differential thermal analysis). Thermal damage greatly affected granodiorite's physical and mechanical properties and microstructure at 800 °C. As a result, UCS measurements were extremely small with a complex failure pattern, making Vp and E unattainable. [ABSTRACT FROM AUTHOR]

The mechanical properties of rocks, such as uniaxial compressive strength and elastic modulus of intact rock, must be determined before any engineering project by employing lab or in situ tests. However, there are some circumstances where it is impossible to prepare the necessary specimens after exposure to high temperatures. Therefore, the propensity to estimate the destructive parameters of thermally heated rocks based on non-destructive factors is a helpful research field. Egyptian granodiorite samples were heated to temperatures of up to 800 °C before being treated to two different cooling methods: via the oven (slow-cooling) and using water (rapid cooling). The cooling condition, temperature, mass, porosity, absorption, dry density (D), and P-waves were used as input parameters in the predictive models for the UCS and E of thermally treated Egyptian granodiorite. Multi-linear regression (MLR), random forest (RF), k-nearest neighbor (KNN), and artificial neural networks (ANNs) were used to create predictive models. The performance of each prediction model was also evaluated using the (R2), (RMSE), (MAPE), and (VAF). The findings revealed that cooling methods and mass as input parameters to predict UCS and E have a minor impact on prediction models. In contrast, the other parameters had a good relationship with UCS and E. Due to severe damage to granodiorite samples, many input and output parameters were impossible to measure after 600 °C. The prediction models were thus developed up to this threshold temperature. Furthermore, the comparative analysis of predictive models demonstrated that the ANN pattern for predicting the UCS and E is the most accurate model, with R2 of 0.99, MAPE of 0.25%, VAF of 97.22%, and RMSE of 2.04. [ABSTRACT FROM AUTHOR]

As an important technology of thick coal seam mining, fully mechanized mining with a large mining height has high mining efficiency. In order to study the roof safety control of large mining height working face, the 122106 working face of Caojiatan coal mine is taken as the engineering background. The numerical simulation method is used to analyze the control ability of roof subsidence when the support strength is 1.2 MPa, 1.4 MPa, 1.6 MPa, 1.8 MPa, 2.0 MPa, and 2.2 MPa. The results show that the support strength of hydraulic support is negatively correlated with roof subsidence. Through theoretical analysis of the mechanical model of the support and surrounding rock under the filling condition, it is shown that the height of the gap between the filling body and roof is the main influencing factor of roof subsidence: the smaller the height of the gap between the filling body and roof, the better the control effect on the roof. Through numerical simulation, the roof subsidence and surface subsidence under different filling rates are analyzed. The results show that when the filling rate increases to 80% the control of roof subsidence achieves better results. Taking production safety and economic benefits into consideration, when the reasonable support strength of the working face is determined to be 2.0 MPa and the filling rate is 80%, the safety control of the working face roof can be ensured. [ABSTRACT FROM AUTHOR]

Mudstone, whose significant characteristic is water-weakening, widely exists in all kinds of geotechnical engineering, which brings great security risks to engineering safety. In this paper, through a series of macro and meso test methods, the macro and meso action mechanism of water on the weakly consolidated plane of mudstone was studied. In the uniaxial compressive strength test, the mudstone cementation plane was the main part of the fracture derived. Under the moist state, the strength of mudstone would decrease significantly, which was inversely correlated with relative moisture content. In the case of flooding, mudstone cracking occurred only along the cementation plane. Through ESEM+mapping test, results showed the humidification curing caused obvious damage to the cemented plane, where sodium and calcium were lost without a certain cause. The cemented plane was rich in kinds of clay minerals in mesoscale and presented an inhomogeneous state. The surface hardness data obtained from nanoindentation were discrete and difficult to quantitatively evaluate the mesomechanical properties. However, compared with the dry state, the data set of the moist state had a significant decline, showing a weakening effect. The mudstone is prone to fail along these weakly consolidated planes. Moisture intrudes into the bedding plane further deteriorating their consolidation. [ABSTRACT FROM AUTHOR]

The aims of this systematic review were to explore the pooled prevalence of multidimensional frailty assessed by the Tilburg Frailty Indicator among community-dwelling older adults. A systematic review and meta-analysis. A comprehensive literature search was conducted across multiple databases, including PubMed, Web of Science, Embase, the Cochrane Library, CINAHL and three Chinese databases. Two independent researchers selected the literatures, extracted the data and evaluated the quality. All statistical analyses were performed using STATA version 16.0. There were 66 studies with a total of 40,597 individuals that were eligible for the meta-analysis. Data from the meta-analysis revealed the pooled prevalence of 42 % for multidimensional frailty (95 % CI: 38 %–45 %, I2 = 98.9 %, T2 = 0.024, p < 0.001). Among the six studies that provided data for different age groups, the results demonstrated an increasing trend in the prevalence of multidimensional frailty with advancing age. The results of gender-stratified analysis proved that the pooled prevalence of multidimensional frailty in women (45 %, 95 % CI: 39 %–51 %, p < 0.001) was higher than that in men (33 %, 95 % CI: 28 %–39 %, p < 0.001). Based on different education levels, the prevalence of multidimensional frailty is highest in the primary elementary or illiterate group (41 %, 95 % CI: 30 %–52 %, p < 0.001). According to different marital status types, the pooled prevalence of multidimensional frailty in the married group was significantly lower (36 %, 95 % CI: 28 %–43 %) than that in the unmarried, divorced or widowed group (51 %, 95 % CI: 37 %–65 %). Through a comprehensive review, we identified that 42 % of elderly individuals living in communities exhibit multidimensional frailty, indicating that multidimensional frailty is relatively common in this population. Stratified analysis revealed that advanced age, female gender, lower education level and unmarried status were associated with higher rates of multidimensional frailty. [ABSTRACT FROM AUTHOR]

Prediction of rockburst in underground engineering is of significance as it is close to the safety of support structures, personnel, and working environments. To improve the accuracy of rockburst classification, this paper proposed an ensemble classifier RF-FA model in which the random forest classifier (RF) and firefly algorithm (FA) were combined to achieve the optimum performance on rockburst prediction. Five key parameters of surrounding rock, i.e., the depth H, the maximum tangential stress σθ, the uniaxial compressive strength σc, the tensile strength σt, and the elastic energy index Wet, are selected as input variables while the rockburst intensity including none, light, moderate, and strong classes was chosen as output. A total of 279 cases worldwide were collected and used for train and test the proposed RF-FA model. The results showed that the FA can optimize the hyperparameters of RF efficiently and the optimum model exhibited a high performance on rockburst data from the independent test set and new engineering projects. The feature importance obtained by the ensemble RF-FA model indicated that the elastic energy index plays the most important role in rockburst. Besides, the proposed model showed much better accuracy on rockburst classification compared with previously existing RF models and empirical criteria, which means it is a useful and robust tool for rockburst prediction. [ABSTRACT FROM AUTHOR]

Herein, the clinically approved nitrogen mustard, chlorambucil (Chl), is covalently embedded into a poly(N-(2-hydroxypropyl)methacrylamide, HPMA) vector via a hydrolysable ester bond to overcome the shortcomings of Chl as well as to achieve better efficacy. The well-defined poly-prodrug amphiphiles with Chl loading content >10 wt% can form uniform nanoparticles with an average diameter of 200 nm through a macromolecular self-assembly strategy. The detailed structure information and Chl release properties are carefully inspected. Cytotoxicity studies against the HepG2 and MCF-7 cell lines combined with flow cytometry reveal that the poly(HPMA)–Chl conjugate exhibits obvious targeting ability and markedly enhanced antitumor effect compared to the free Chl. After labelling with a fluorescent group, the cell uptake, lysosome escape and distribution in living organs of the poly-prodrug were also studied. [ABSTRACT FROM AUTHOR]

Soilcrete is produced by adding a curing agent, such as cement, to the soil and mixing it thoroughly to form a solid, stable substance, but usually with poor early strength. To improve the early strength and stability of soilcrete, in this paper, solid waste materials such as mineral powder, and natural gypsum powder were added proportionately to replace parts of cement (called composite curing agent). The unconfined compressive strength (UCS), and dry-wet cycle strength of soilcrete were tested to evaluate the optimum mix design. The scanning electron microscope (SEM) and XRD test were applied for investigating the mechanism of early strength of solid waste-based soilcrete. The results show that the optimal mix ratio of cement and mineral powder is 4:6, the 7-day UCS is 1.61 MPa, and the 28-day UCS is 3.37 MPa. The composite curing agent mixed with gypsum powder and water glass has a good curing effect on silt and clay respectively, and the 28-day strength of the clay specimen can reach 3.97. During the dry-wet cycle test, the strength of the soilcrete increases first and then decreases with the number of cycles. The SEM results show that the soilcrete particles were denser, had more hydration products, and the soil particle morphology changed from loose to aggregated, accompanied by a decrease in pores. The study provides a cheaper and high-performance composite curing agent based on solid waste materials for soilcerte than conventional cement, which can promote the application in such field. • An early-strength, low-cost solicrete was proposed using solid waste materials, namely mineral powder and natural gypsum. • The UCS (Unconfined Compressive Strength), dry-wet cycle strength, and soil types of soilcrete were tested systematically. • The mechanism of the new solid waste material on soilcrete was revealed through SEM, XRD, and hydration analysis. [ABSTRACT FROM AUTHOR]

• Effect of the rock strength on the fatigue performance of rock bolt systems. • Effect of the cyclic load frequency and amplitude on the damage of rock bolt systems. • Acoustic Emission for the damage evolution in rock bolt systems under cyclic loading. • Cumulative AE energy slope method for macro crack initiation assessment. Rock bolt support is one of the key methods to maintain the stability of underground space. The durability of the rock bolt can be weakened by cyclic loading, resulting in premature failure of the underground structures. A comprehensive understanding of the performance of the bolting system under cyclic loading is essential to assess the safety of the bolting system and underground structures. In this context, this study investigated the mechanical performance of rock bolts installed in simulated soft and medium hard rock and subjected to cyclic loading. The Acoustic Emission (AE) technique was used to monitor internal damage to the bolt system under different loading conditions. A cumulative AE energy slope method has been proposed to determine the onset of the macro crack formation stage. The rock bolt demonstrated an extended fatigue life in soft rock, but its condition worsened when implanted in medium hard rock. The cyclic loading resulted in a slight improvement in the load bearing capacity of the soft rock bolt system and a significant deterioration in the medium hard rock bolt counterpart. The main fatigue failure modes of the rock bolt systems were splitting and shear failure of the surrounding rock, and debonding of the interface. Increasing the amplitude of the cyclic loading reduced the macro crack initiation cycle for both rock bolt systems, whereas increasing the frequency had different effects. The damage variable increased with frequency and amplitude for both rock bolt systems. The toughness of the soft rock bolt degraded during cyclic loading, while the high frequency cyclic loading did not modify the toughness of the medium hard rock bolt. [ABSTRACT FROM AUTHOR]

The micromechanism of the effects of different height/width ratios (H/W) and initial stress levels on unloading characteristics of deep rock was investigated based on PFC3D true-triaxial unloading simulation. The results show that the increase of H/W will increase the movement speed of rock particles and intensify the acoustic emission (AE) activity inside the rock. With the increase of H/W, the failure mode of rock changes from splitting failure to tensile-shear failure. With increasing initial stress level, the particle velocity and overall fragmentation degree of rock increase. However, the increase of lateral stress will limit the coalescence of microfractures and weaken AE activity in the rock. Under unloading condition, the bonds between particles generally crack along the unloading direction, and the tensile effect is more pronounced under the condition of low initial stress level and high H/W. Under unloading condition, the variable energy of rock increases with increasing H/W and initial stress level, and the kinetic energy of rock particles increases with increasing H/W. The increase of initial stress level will increase the kinetic energy of rock particles when H/W is high. [ABSTRACT FROM AUTHOR]

• Microglia are brain resident innate immune cells and play critical roles in neuroinflammation after ischemic stroke. • Activated microglia express various receptors, channel proteins, and enzymes mediating the inflammatory processes. • After ischemic stroke, intracellular elements can act as DAMPs triggering the PRRss on microglia. • Numerous biochemical and physical therapies have been demonstrated to have therapeutic potentials by targeting microglia. • Though targeting microglia is a promising approach in the treatment of ischemic stroke, the clinical progress is slow. Stroke is the largest contributor to global neurological disability-adjusted life-years, posing a huge economic and social burden to the world. Though pharmacological recanalization with recombinant tissue plasminogen activator and mechanical thrombectomy have greatly improved the prognosis of patients with ischemic stroke, clinically, there is still no effective treatment for the secondary injury caused by cerebral ischemia. In recent years, more and more evidences show that neuroinflammation plays a pivotal role in the pathogenesis and progression of ischemic cerebral injury. Microglia are brain resident innate immune cells and act the role peripheral macrophages. They play critical roles in mediating neuroinflammation after ischemic stroke. Microglia-mediated neuroinflammation is not an isolated process and has complex relationships with other pathophysiological processes as oxidative/nitrative stress, excitotoxicity, necrosis, apoptosis, pyroptosis, autophagy, and adaptive immune response. Upon activation, microglia differentially express various receptors, channel proteins, and enzymes involved in promoting or inhibiting the inflammatory processes, making them the targets of intervention for ischemic stroke. To inhibit microglia-related neuroinflammation and promote neurological recovery after ischemic stroke, numerous biochemical agents, cellular therapies, and physical methods have been demonstrated to have therapeutic potentials. Though accumulating experimental evidences have demonstrated that targeting microglia is a promising approach in the treatment of ischemic stroke, the clinical progress is slow. Till now, no clinical study could provide convincing evidence that any biochemical or physical therapies could exert neuroprotective effect by specifically targeting microglia following ischemic stroke. [ABSTRACT FROM AUTHOR]

The size and distribution of pores in rocks are closely related to their physical and mechanical properties. It is important to study the structure and distribution of pore size inside the rock to assess the risk of damage to a given rock volume. These characteristics were studied under different pressures, pore diameters, and pore throat size distribution laws using a UTM5540 electronic universal testing machine, magnetic resonance imaging scanning, and low field nuclear magnetic resonance spectroscopy with cyclic loading on yellow sandstone. We found the following. (1) Under 0–10 MPa load, the peaks of the sandstone T 2 spectrum move left as load increases, and the porosity of the sandstone decreases. The peak area of the middle relaxation spectrum increases as pressure increases from 10 to 20 MPa, and a peak for the long relaxation time spectrum appears. (2) Under 0–10 MPa load, the spectral peak associated with a large pore moves left and decreases in area as pressure increases. Under 10–20 MPa load, the large-pore spectral peak moves right and increases in area as pressure increases. (3) Under the applied 0–10 MPa load, the porosity of water-saturated sandstone gradually decreases, and the sandstone NMR images darken with increasing load. The porosity of saturated sandstone gradually increases under 10–20 MPa pressure, and its NMR image brightens. (4) The number of small pore throats increases with increasing load, but the number of large- and medium-sized pore throats decreases. From 0 to 15 MPa, crack (>1 micron) abundance decreases, and fractures are generated by compaction under a 20 MPa load. The pore interconnectivity is enhanced, as are the number and size of pores in the sandstone. With continuing increasing pressure, the numbers of pores and penetration of cracks increase, which damages the sandstone. [ABSTRACT FROM AUTHOR]

Moyamoya disease (MMD) is characterized by progressive stenosis or occlusion of the distal internal carotid artery and simultaneous formation of collateral vasculature. The fragile alteration and increased hemodynamic stress in the intra- and extracranial vasculature would conjointly result in the formation of intracranial aneurysms in MMD patients. According to our classification, the MMD-associated aneurysms are divided into the major artery aneurysms (MAAs) and non-MAAs. The non-MAAs are further subdivided into the distal choroidal artery aneurysms, moyamoya vessel aneurysms, transdural collateral aneurysms, and anastomosis aneurysms. Currently, endovascular treatment (EVT) has become the main stream for the MMD-associated aneurysms. There is no difference to EVT for the MMD-associated MAAs of the non-stenosed major arteries with that in the non-MMD patients. While it is a big challenge to perform EVT for MMD-associated aneurysms in the stenosed arteries. Generally speaking, the parent arteries of the non-MAAs are slim, and super-selective catheterization is technically difficult. Most of the times, parent artery occlusion with liquid embolic agents or coils can only be performed. The vasculature in MMD patients is fragile; perioperative management and meticulous intraoperative manipulation are also very important to avoid complications during EVT. In spites of the complications, the EVT can bring good outcome in selected cases of MMD-associated aneurysms. [ABSTRACT FROM AUTHOR]

This systematic literature review was aimed to investigate the use of cell culture and animal models to evaluate the efficacy of alginate‐and chitosan‐based scaffolds on diabetic wound healing. We electronically searched the articles published until July 2019. The databases included five English databases such as PubMed, Web of Science, Embase, the Cochrane Library, CINAHL, and three Chinese databases like CNKI, WanFang Data, and VIP. The related articles were manually searched to identify studies that were not searched by electronic database searches. Twenty‐nine studies met the inclusion criteria. We divided the results into three groups: chitosan, alginate, and a combination of chitosan and alginate. Chitosan‐, alginate‐, and a combination of chitosan and alginate‐based scaffolds showed good intervention effects on wound healing. Chitosan‐based scaffolds were effective in diabetic skin wound healing. The effects of alginate and the combination of chitosan‐and alginate‐based scaffolds on diabetic skin wounds still need more research. However, due to the heterogeneity of animal and cell preclinical trials and the validity of the statistical analysis used in these studies, it is necessary to conduct a thorough study using well‐designed experiments to confirm these results. In addition, properly designed chitosan‐and/or alginate‐based scaffolds with thorough preclinical evaluations are required prior to clinical applications. [ABSTRACT FROM AUTHOR]

Improving roadway stability in deep underground mines is quite challenging, as the conventional support structures easily fail. Roadway collapse and large deformation occur just several months after tunnel excavation. In this study, a relatively new prereinforcement technique, the jet grouting (JG), is introduced to improve roadway stability. A field test was performed for evaluating the practicability and applicability of JG in soft coal mass. A series of laboratory tests were conducted to assess the properties of coalcrete (coal-grout after JG treatment). A two-dimensional numerical model was established for validating the input parameters. Based on the verified model, three JG support cases for roadway were modeled and compared with a conventional support case, namely, the currently used support in this mine "rock bolts + U-shaped steel set + shotcrete." The results show that the proposed prereinforced JG support structures can considerably control the deformation and failure zone of the roadway and improve the bearing capacity of coal mass. The mechanism of maintaining roadway stability using JG techniques is further revealed. Some suggestions are further presented to improve the stability of the jet-grouted roadway. [ABSTRACT FROM AUTHOR]

The efficiency of coal mining is seriously affected by roadway stability, as large time‐dependent deformation of roadway frequently occurs and needs to be maintained several times during its service life. Such rheological deformation was common in soft coal mass at Huaibei coalfield in China. To address this issue, in this study, the time‐dependent deformation of the soft coal roadway was analyzed and a new Jet Grouting (JG) technique was presented for controlling deformation. The time‐dependent deformation of the soft coal roadway was numerically simulated and validated. Based on the field test results and the verified model, a JG support model was established to examine its effect on roadway deformation. The JG support system can reduce the horizontal and vertical displacement of the roadway effectively and constrain the time‐dependent deformation of coal mass. The deformation rate and stabilization time of roadway decreased significantly by comparison with conventional support. This work presented a promising JG support scheme for controlling the time‐dependent deformation in the roadway in deep underground mine, which can greatly promote the JG design and application. [ABSTRACT FROM AUTHOR]

Background: Mesenchymal stem cells (MSCs) are suspected to exert neuroprotective effects in brain injury, in part through the secretion of extracellular vesicles like exosomes containing bioactive compounds. We now investigate the mechanism by which bone marrow MSCs (BMSCs)-derived exosomes harboring the small non-coding RNA miR-29b-3p protect against hypoxic-ischemic brain injury in rats.Methods: We established a rat model of middle cerebral artery occlusion (MCAO) and primary cortical neuron or brain microvascular endothelial cell (BMEC) models of oxygen and glucose deprivation (OGD). Exosomes were isolated from the culture medium of BMSCs. We treated the MCAO rats with BMSC-derived exosomes in vivo, and likewise the OGD-treated neurons and BMECs in vitro. We then measured apoptosis- and angiogenesis-related features using TUNEL and CD31 immunohistochemical staining and in vitro Matrigel angiogenesis assays.Results: The dual luciferase reporter gene assay showed that miR-29b-3p targeted the protein phosphatase and tensin homolog (PTEN). miR-29b-3p was downregulated and PTEN was upregulated in the brain of MCAO rats and in OGD-treated cultured neurons. MCAO rats and OGD-treated neurons showed promoted apoptosis and decreased angiogenesis, but overexpression of miR-29b-3p or silencing of PTEN could reverse these alterations. Furthermore, miR-29b-3p could negatively regulate PTEN and activate the Akt signaling pathway. BMSCs-derived exosomes also exerted protective effects against apoptosis of OGD neurons and cell apoptosis in the brain samples from MCAO rats, where we also observed promotion of angiogenesis.Conclusion: BMSC-derived exosomal miR-29b-3p ameliorates ischemic brain injury by promoting angiogenesis and suppressing neuronal apoptosis, a finding which may be of great significance in the treatment of hypoxic-ischemic brain injury. [ABSTRACT FROM AUTHOR]

Roadway stability in extremely soft coal mass is a typical challenge in deep underground mines, as the most widely adopted support structure such as rock bolting, compound support system normally fails. This paper proposed a novel prereinforcement method for coal roadway, that is, jet grouting (JG) technique, to improve the quality of surrounding soft coal mass and form a stable support structure namely jet grouted coalcrete. The field and laboratory tests were conducted for evaluating the applicability of JG and the mechanical parameters of coalcrete. A numerical model was verified by comparing the calculated results with field measurements. According to the confirmed model, three typical JG support schemes were performed to assess the roadway stability after JG. The results showed that the proposed JG schemes can reduce the deformation and failure zone of the roadway and optimize the stress states around the roadway. The mechanism related to these advantages was investigated. This study provides a promising idea for supporting soft coal roadway in deep underground coal mines, which can promote the JG application in the field. [ABSTRACT FROM AUTHOR]

Anterior inferior cerebellar artery (AICA) can present with a myriad of variations. However, the previous studies of AICA anatomy were based on small-scale cadaveric investigation. In this study, we performed an angiographic study of AICA in 500 Chinese with Han nationality based on digital subtraction angiography (DSA). Patients admitted to our institution between 2015 and 2018 who had underwent DSA were potential candidates for this retrospective evaluation. The exclusion criteria were: a) patients with vascular diseases of the posterior circulation; b) ischemic diseases or moyamoya disease of the anterior circulation. Five hundred patients were identified. The patients ranged in age from 6 to 75 years. Two hundred thirty-seven (62.9%, 237 of 377) patients had bilateral AICAs at the same level, and 140 (37.1%, 140 of 377) had bilateral AICAs at different levels. The developing states of AICA were grade 0 in 31 (3.5%, 31 of 896), grade 1 in 373 (41.6%, 373 of 896), grade 2 in 313 (34.9%, 313 of 896), and grade 3 in 179 (20.0%, 179 of 896) hemispheres. Two hundred twenty-one (22.1%, 221 of 1000) presented with AICA-PICA common trunks. Thirty-one (3.1%, 31 of 1000) hemispheres showed no obvious AICA angiographically. AICA arose as a single trunk in 865 (86.5%, 865 of 1000) hemispheres, and as duplicate trunks in 104 (10.4%, 10 of 1000) hemispheres. Triplicate or more trunks were not seen. AICA originating from the basilar artery fenestration accounted for 4% (20 of 500) of the cases. This is the first attempt using DSA data to perform a large-scale investigation of AICA variations. The ever-growing need of endovascular intervention calls for more suitable anatomical explanation of the vascular structures. [ABSTRACT FROM AUTHOR]

Purpose: To identify the effects of whole body vibration (WBV) on health-related quality of life (HRQOL) in patients with chronic conditions.Methods: Five databases (the Cochrane Library, PubMed, Medline, EBSCO, and Web of science) were searched (from inception until April 30, 2019) for original articles. All studies were randomized controlled trials reporting the effects of WBV on HRQOL. Two independent reviewers extracted trial data and assessed the risk of bias using the risk of bias tool recommended by the Cochrane Back Review Group.Results: Of the 349 articles that were screened, 17 articles, including 763 participants with various chronic conditions, met the inclusion criteria. Six studies reported significant improvements in HRQOL. No evidence was observed to suggest that WBV was more effective than other types of exercises. The study participants, exercise protocols, HRQOL instruments, study duration, and frequency as well as amplitude of WBV varied across the studies. Meta-analysis was not conducted due to the heterogeneity of study designs and outcome measures.Conclusions: This study has demonstrated that WBV may improve HRQOL in patients with chronic conditions. However, the evidence was not strong enough to warrant recommendation and thus further high-quality studies with larger sample sizes and longer intervention durations are needed. [ABSTRACT FROM AUTHOR]

The anticancer drug 6-MP was covalently bonded to the –OH group of poly(HPMA) via a glutathione-responsive carbonyl vinyl sulfide linker. In vitro simulation assay demonstrated that the poly(HPMA)–PTA conjugate exhibited a markedly enhanced antitumor effect on HepG2 cells. [ABSTRACT FROM AUTHOR]

Superior cerebellar artery (SCA) aneurysms can be divided into 2 types: basilar artery (BA)-SCA junction aneurysms and peripheral SCA aneurysms. The peripheral SCA aneurysm is a distinct entity from its BA-SCA counterpart. No comprehensive literature review for endovascular management of peripheral SCA aneurysms has been conducted. A PubMed search of the published articles written in English was performed on February 13, 2019 for patients who underwent endovascular treatment for peripheral SCA aneurysms. Segmentation of SCA was in accordance with the proposed nomenclature by Rodriguez-Hernandez et al. A modified Rankin Scale score ≤1 was defined as good recovery. Thirty-five articles reporting 55 patients including 2 cases in our center were included in the final analysis. The affected patients (28 females, 50.9%) were aged from 3 months to 79 years (46.22 ± 13.51 years). Forty-five patients (81.8%) presented with spontaneous subarachnoid hemorrhage with or without cerebellar hematoma. Forty-six patients (83.6%) experienced good recovery. Permanent or transient procedure-related complications occurred in 17/49 patients (34.7%) during endovascular treatment (EVT). However, no fatal or server procedure-related complication occurred in the long-term. Peripheral SCA aneurysms are rare cerebrovascular lesions and should be treated as a specific entity. EVT is an efficient and safe option in peripheral SCA aneurysms. Permanent and fatal procedure-related complications are rare. Further prospective and larger-scale studies are warranted to better elucidate the role of EVT in peripheral SCA aneurysms. [ABSTRACT FROM AUTHOR]

Anterior inferior cerebellar artery (AICA) trunk aneurysms are rare entities. Given the eloquence of the AICA in supplying the cerebellum and brainstem, in theory, sacrifice or occlusion of the a1-a2 segment in lesions involving the AICA may lead to various complications. However, some patients might experience no complication or favorable recovery. The subgroup of patients who would benefit from parent artery occlusion (PAO) among those with aneurysms involving the a1-a2 segment of the AICA remains to be explored. In this report, we present 2 cases of AICA dissecting aneurysms at the a1-a2 segment that were successfully occluded via coiling without postprocedural complications. A comprehensive literature review was also performed on patients with AICA aneurysms with occlusion at the a1-a2 segment. Sixteen patients were identified, and all of the cases had satisfactory outcomes. Of these patients, 11 of 16 (68.75%) had no neurologic deficits, and 5 of 16 (31.25%) had acceptable neurologic deficits. The prognosis was associated with collateral circulation of the AICA, and collateral circulation was discussed. In case of an a1-a2 aneurysm that is hard to occlude without sacrificing the parent artery, careful hemodynamic and morphologic evaluation for collateral flow is warranted. If collateral flow is demonstrated or the aneurysm is flow-related with cerebellar arteriovenous malformation, PAO of the a1-a2 segment can be an acceptable option. [ABSTRACT FROM AUTHOR]

Mitochondrial translation system executes the biosynthesis of mitochondrial DNA encoded polypeptides that are the core subunits of oxidative phosphorylation complexes. Recently, we reported that elongation factor 4 (EF4) is a key quality control factor in bacterial and mitochondrial translation regulating tRNA translocation and modulating cellular responses via a direct cross-talk with cytoplasmic translation machinery. Here, we made a brief review on mtEF4-regulated mitochondrial translation, respiratory chain biogenesis and the production of reactive oxygen species (ROS). We will discuss the influence of mtEF4 on the electron transport chain, especially at respiratory chain complex IV, which could result in cytochrome c peroxidase formation, electron leakage from electron transport chain and ROS increase. [ABSTRACT FROM AUTHOR]

To synthesize the pooled mortality risk estimate and determine whether cognitive frailty is a predictor of mortality. A systematic review and meta-analysis. The participants were community-dwelling older adults aged ≥60 years. PubMed, Web of Science, Embase, CINAHL, and the Cochrane Library databases were systematically searched. Two researchers independently screened potentially eligible literature, evaluated the quality of the included studies, and then extracted the data. We used STATA, version 15.0 to perform the all data. Nineteen studies were included. The association between cognitive frailty and a higher risk of death was statistically significant [hazard ratio (HR), 2.01; 95% CI, 1.84–2.19; P <.001]. The outcomes indicated that cognitive frailty was a critical risk factor for predicting mortality (OR, 4.82; 95% CI, 1.59–14.57; P <.01). Based on different models of cognitive frailty, the results of subgroup analyses revealed that the risk of mortality was the highest in the Frail + mild cognitive impairment group (HR, 2.35; 95% CI, 2.05–2.70; P <.001). The subgroup analyses by region demonstrated that mortality risk was lowest in the European group (HR, 1.63; 95% CI, 1.4–1.87; P <.001). This study quantitatively portrays the pooled mortality risk estimate of cognitive frailty. The results suggest that in older adults, cognitive frailty can be a predictor of mortality. The findings could alert health care providers to pay more attention to cognitive frailty. [ABSTRACT FROM AUTHOR]

Background Intracranial cavernous malformations (CMs) are usually located at the cerebral parenchyma; dural-based CMs outside the middle fossa are rarely reported. To our knowledge, dural-based CMs located at the cerebral convexity are even rarer in that only 2 pediatric cases have ever been reported. In this report, we present 2 extremely rare cases of dural-based CMs at the cerebral convexity in pediatric patients. The clinical course, radiologic and pathologic features, treatment, and follow-up are described. Case Description The first case is a 6-year-old boy who presented with headache and vomiting and was found to have an acute subdural hematoma and space-occupying lesion. Intraoperative findings and histologic examination were consistent with a CM. He experienced an uneventful postoperative recovery. The second case is a 43-day-old female neonate who presented with a progressively enlarging neoplasm at the right occipital region since birth. Computed tomography of the head performed at admission showed a slight hyperdense occupying lesion communicating between the intra- and extracranial cavity through a skull defect. The lesion was resected en bloc and histologic examination was in accord with a CM. Conclusions The clinical manifestations and radiologic characteristics of dural-based CMs are nonspecific. Unlike that of their cerebral parenchymal counterparts, the radiologic appearance of dural-based CMs is confusing and misleading. Surgical resection is the primary treatment selection for dural-based CMs. In cases with no close relationship to dural sinuses, complete surgical resection with minimal blood loss and few neurologic deficits could be easily achieved. [ABSTRACT FROM AUTHOR]

In this work, we developed a phosphine‐catalyzed C‐methoxylation process of para‐quinone methides (p‐QMs). By employing a metal‐free phosphine catalyst [P(4‐MeC6H4)3] together with methanol and deuterated methanol (d4, d1, and d3) as C1 sources, a series of methoxylated diarylmethanes and the corresponding deuterated products were obtained without additional solvent under mild reaction conditions. [ABSTRACT FROM AUTHOR]

Background: With triphasic, dynamic contrast-enhanced CT scan to identify benign and malignant gallbladder polypoid lesions, we hope to determine an accurate diagnosis before surgery.Study Design: Ninety patients with gallbladder polypoid lesions were treated surgically in the Department of Hepatobiliary Surgery, the First Affiliated Hospital of China Medical University, Shenyang, China, from July 2013 to July 2016, and divided into 2 groups according to postoperative pathologic results: a malignant group with 44 patients and a benign group with 46 patients. Triphasic, dynamic contrast-enhanced CT scan was performed in 90 patients within 2 weeks before surgery. The CT image parameters were measured and analyzed by 2 senior radiologists and a hepatobiliary surgeon in blind.Results: Mean age of the malignant group was significantly older than that of the benign lesion group (p < 0.01). With the CT image parameters, the maximal diameter of the lesion was significantly longer in malignant lesions than in benign lesions (p < 0.01). There was a significant difference in plain CT, delayed phase CT, and ΔCT values (ΔCT = portal venous phase CT value minus delayed phase CT value) between the 2 groups (all p < 0.01). In terms of differentiating malignant and benign gallbladder polypoid lesions, the ΔCT value was superior to that of plain and delayed phase CT in both sensitivity and specificity (p < 0.05).Conclusions: In triphasic, dynamic contrast-enhanced CT scan, plain CT value, delayed phase CT value, and ΔCT value could detect malignant lesions of gallbladder polyps, with the highest sensitivity and specificity of ΔCT. [ABSTRACT FROM AUTHOR]

Purpose: Diabetic patients tend to have a poor quality of life. A sedentary lifestyle is considered to be a modifiable risk factor for type 2 diabetes and an independent predictor of poor quality of life. Exercise is a key treatment for people living with diabetes. The purpose of this study was to conduct a systematic review to assess the effect of exercise on the quality of life of people with type 2 diabetes.Methods: We conducted a systematic review using the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. PubMed, Web of Science, Embase, Cochrane Library, CINAHL and three Chinese databases were searched for studies published until January 2016. The review included all clinical trials that evaluated the effect of exercise on quality of life compared with that of usual care for people with type 2 diabetes. Two reviewers independently assessed the quality of all the included studies, by using the Downs and Black Quality Index (QI).Results: Thirty studies met inclusion criteria, with 2785 participants. We divided the exercise into four modes: aerobic, resistance, a combination of aerobic and resistance and yoga. Aerobic exercise showed a significant effect between groups. Resistance and combined exercise showed mixed results. Yoga also showed good intervention effects on quality of life.Conclusions: The effect of aerobic exercise on the quality of life in people with type 2 diabetes was safe and effective. Then, most of the studies on aerobic exercise were of good methodological quality. The effects of resistance exercise and combined exercise on the quality of life in people with type 2 diabetes were mixed, and the effect of yoga on quality of life still need more research. [ABSTRACT FROM AUTHOR]

Older residents in long-term care facilities often experience physical and mental health problems along with vulnerability to psychological and social stressors. Due to the shortage of human resources, the application of virtual reality technology may be a new way to promote healthy aging for older residents in long-term care facilities. To identify the effects of virtual reality-based interventions for improving physical and mental health outcomes among older residents in long-term care facilities. Systematic review. A systematic review was reported in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses 2020 Statement. Four databases (the Cochrane Library, PubMed, EMBASE, and Web of Science) were searched from their inception until May 2022 for original articles. Randomized controlled trials (RCTs) and quasi-experimental trials reporting the effects of virtual reality-based interventions on physical and mental health outcomes were included. Two independent reviewers extracted trial data and assessed the risk of bias using the risk of bias tool recommended by the Cochrane Back Review Group and the Methodological Index for Non-Randomized Studies. Of the 8511 articles that were screened, 30 articles including 1057 participants met the inclusion criteria. Many studies have investigated multiple outcomes. Eighteen of the twenty-five studies that assessed physical health-related outcomes (n = 18/25, 72%) reported positive intervention effects, and fourteen (n = 14/25, 56%) reported negative postintervention effects. Eight of the sixteen studies that assessed mental health-related outcomes (n = 8/16, 50%) reported positive intervention effects, while twelve (n = 12/16, 75%) reported negative intervention effects. Meta-analysis was not conducted due to the heterogeneity of the study designs and outcome measures. This study demonstrated that virtual reality-based interventions could be a safe and effective approach to improve the physical outcomes of older residents in long-term care facilities, but this evidence lacks certainty. The effectiveness of virtual reality-based interventions for mental health outcomes is uncertain. Virtual reality-based interventions have the potential to provide individualized, error-free self-training for older residents in long-term care facilities, but the usability for these residents requires further study. Future studies should use RCT designs and aim to include larger sample sizes and have longer intervention durations. PROSPERO registration ID: CRD42022331917. Virtual reality-based interventions are possibly effective for improving physical health of older residents in long-term care facilities. [ABSTRACT FROM AUTHOR]

Background Ocular movement nerve (cranial nerve III, IV and VI) palsy (OMNP) is rarely encountered after mild head trauma. As a result of the inconsistent definition of this specific entity in published studies, it is difficult to offer an accurate management strategy and prognosis assessment to affected patients. Methods A retrospective review of the medical records of the patients at the First Hospital of Jilin University combined with a systematic review of published studies was conducted. Results Thirty-one patients (17 females, 55%), including 6 cases in our institution, were identified in this systematic review. Cranial nerves III, IV, and VI were involved in 54.8%, 3.2%, and 45.2% of the patients, respectively. Although all the patients in our case series experienced complete resolution, only 54.6% experienced complete resolution in a time course of 10 days to 13 months. Additional intracranial findings other than traumatic brain injury on imaging modalities that might predispose to OMNP after mild head trauma were identified in 25.8% of the patients. Conclusions OMNP after mild head trauma is a rare entity in neurosurgical practice. In patients with no positive intracranial finding, observation and follow-up are the mainstay of management. If any underlying intracranial lesions are identified, the management should be focused on the underlying lesions. From the data available, mild trauma does not mean mild injury or favorable recovery in OMNP after mild head trauma. [ABSTRACT FROM AUTHOR]

The linear absorption spectra of metallic zigzag single-walled carbon nanotubes (SWNTs) have been theoretically studied under the uniaxial strain by using the standard formulas of Orr and Ward. Due to the trigonal warping effect, the linear absorption spectra of M 11 and M 22 transitions are dominated by two major peaks, which come from the split M ii − and M ii + excitons with different band index q . As the uniaxial strain is applied, it is interesting to find that the split peaks will overlap at one point of the uniaxial strain, and the splitting is zero at this point. Hence, we can also describe this variation tendency as the size of splitting, which first decreases to zero and then increases with increasing the uniaxial strain, based on which a supplemented tool is offered to detect the deformation degree of a metallic SWNT under uniaxial strain. In addition, the linear absorption spectra of the bands that nearest to the Fermi level have also been calculated, displaying an increase with the increase of the uniaxial strain, which can offer some useful information for the THz applications. The results obtained here are expected to be confirmed by the future experiment. [ABSTRACT FROM AUTHOR]

• Personally tailored exercises are effective for improving physical outcomes. • Personally tailored exercises are effective for reducing disease symptoms. • Personally tailored exercises have no advantage in improving exercise adherence. • Personally tailored exercises have no advantage in improving economic benefits. To identify the effects of personally tailored exercise programmes for improving physical outcomes amongst older people living in the community. Four databases (the Cochrane Library, PubMed, EMBASE, and Web of Science) were searched (from inception until Jan 25th, 2022) for original articles. All studies were randomized controlled trials (RCTs) and quasi-experimental trials reporting the effects of personally tailored exercise programmes on physical outcomes. Two independent reviewers extracted trial data and assessed the risk of bias using the risk of bias tool recommended by the Cochrane Back Review Group and the Methodological Index for Non-Randomized Studies (MINORS). Of the 7310 articles that were screened, 10 articles including 959 participants met the inclusion criteria. Nine of the included studies reported significant improvements in physical outcomes including balance, strength, mobility and physical activity, and disease symptoms. Meta-analysis was not conducted due to the heterogeneity of study designs and outcome measures. This study demonstrated that personally tailored exercises based on assessments of physical function may be a safe and effective approach to improve physical outcomes in older adults living in the community. However, personally tailored exercise has no advantage in improving exercise adherence or economic benefits, and thus, further high-quality RCTs with larger sample sizes and qualitative studies are needed to better understand the effectiveness of personally tailored exercise and the attitude of elderly individuals towards such exercise. Future research should consider not only physical functions but also psychological factors when developing personalized exercise programs. [ABSTRACT FROM AUTHOR]

The exciton energy spectrum and its binding energy under the uniaxial strain have been theoretically studied by using the tight-binding model in the metallic zigzag single-walled carbon nanotubes (SWNTs). It is found that the energy of M 11 - and M 22 - excitons and their binding energies increase with the increase of uniaxial strain, but the energy of M 11 + and M 22 + excitons and their binding energies decrease as the uniaxial strain increase. So, we can deduce that the splitting of M 11 and M 22 exciton will disappear as the uniaxial strain increases up to some degree, which is expected to be detected by the future experiment. On the other hand, it is interesting to calculate the exciton energy spectrum and binding energies of the bands that nearest to the Fermi level, with a narrow gap under the uniaxial strain. The obtained results show that they increase with increasing the uniaxial strain, based on which a supplemented tool is offered to detect the deformation degree of a metallic SWNT under uniaxial strain. In addition, we expect the results obtained here can offer some useful information for the future THz applications. [ABSTRACT FROM AUTHOR]

The aim of this systematic review and meta-analysis was to investigate the pooled prevalence of cognitive frailty among community-dwelling older adults and provide evidence-based support for policy-makers planning health and social care policies. A systematic review and meta-analysis. PubMed, Web of Science, Embase and the Cochrane Library were systematically searched from their inception to December 10, 2020. Descriptive studies (cross-sectional studies or population-based longitudinal studies) and cohort studies were available. Participants were community-dwelling older adults aged 60 years and above. Two researchers independently screened the literature, extracted the data and evaluated the quality of the included studies. All statistical analyses were conducted using Stata 15.0. We screened 2815 records, among which 24 studies met the inclusion criteria and were included in the review. The pooled prevalence of cognitive frailty was 9% (95% CI: 8%-11%, I2 = 99.3%). The results of the subgroup analysis showed that the pooled prevalence of cognitive frailty was 11% (95% CI: 9%-14%) in men and 15% (95% CI: 11%-19%) in women. The pooled prevalence of cognitive frailty based on the descriptive studies and cohort studies was 7% (95% CI: 5%-9%) and 17% (95% CI: 11%-22%), respectively. The pooled estimates of cognitive frailty prevalence were 6% (95% CI: 4%-8%) from 2012 to 2017 and 11% (95% CI: 9%-14%) from 2018 to 2020. This systematic review analyzed the available literature and revealed that the pooled prevalence of cognitive frailty among community-dwelling older adults was 9%. The stratified analysis showed that the prevalence of cognitive frailty was higher in older women. In addition, the prevalence has increased in recent years, which has important implications for adapting health and social care systems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three porphyrins containing heavy atoms were synthesized (P1-P3), and their solubility were improved through the alkylation reaction of N-pyridyl substitution. • These porphyrin molecules as photosensitizers have excellent performance in PDT research, especially P3 molecules. • In vitro, the molecules could induce the high level of ROS production and cell apoptosis after photodynamic therapy for HepG2. However, it is not toxicity normal cell HUVECS. Porphyrin and its derivatives have become the second-generation photosensitizers for photodynamic therapy (PDT). Three water-soluble porphyrins containing halogen atoms (F, Cl, Br) were synthesized by N-pyridyl substituted alkylation reaction. We found that P3 has the highest singlet oxygen generation capacity and the results of density functional theory (DFT) further support this result. MTT assay was used to study cytotoxicity, which proved that P1-P3 have good phototoxicity and high selectivity. Fluorescence imaging and intracellular reactive oxygen species illustrate cell apoptosis and reactive oxygen species (ROS) production. High ROS production, excellent phototoxicity ensure that photosensitizers become potential candidates for PDT drugs. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

Accurately evaluating rockburst intensity has attracted much attention in these recent years, as it can guide the design of engineering in deep underground conditions and avoid injury to people. In this study, a new ensemble classifier combining a random forest classifier (RF) and beetle antennae search algorithm (BAS) has been designed and applied to improve the accuracy of rockburst classification. A large dataset was collected from across the world to achieve a comprehensive representation, in which five key influencing factors were selected as the input variables, and the rockburst intensity was selected as the output. The proposed model BAS-RF was then validated by the dataset. The results show that BAS could tune the hyperparameters of RF efficiently, and the optimum model exhibited a high performance on an independent test set of rockburst data and new engineering projects. According to the ensemble RF-BAS model, the feature importance was calculated. Furthermore, the accuracy of the proposed model on rockburst prediction was higher than the conventional machine learning models and empirical models, which means that the proposed model is efficient and accurate. [ABSTRACT FROM AUTHOR]

Background: Brain lactate concentrations are enhanced in response to cerebral ischemia and promote the formation of reactive astrocytes, which are major components of the neuroinflammatory response and functional recovery, following cerebral ischemia. NDRG2 is upregulated during reactive astrocyte formation. However, its regulation and function are unclear. We studied the relationship between lactate and NDRG2 in astrocytes under conditions of ischemia or oxygen–glucose deprivation (OGD). Methods: We examined astrocytic NDRG2 expression after middle cerebral artery occlusion (MCAO) using western blot and immunofluorescence staining. Under hypoxia conditions, we added exogenous L-lactate sodium (lactate) to cultured primary astrocytes to explore the effects of lactate on the ubiquitination modification of NDRG2. We profiled the transcriptomic features of NDRG2 silencing in astrocytes after 8 h of OGD conditions as well as exogenous lactate treatment by performing RNA-seq. Finally, we evaluated the molecular mechanisms of NDRG2 in regulating TNFα under OGD conditions using western blot and immunohistochemistry. Results: Reactive astrocytes strongly expressed NDRG2 in a rat model of MCAO. We also showed that lactate stabilizes astrocytic NDRG2 by inhibiting its ubiquitination. NDRG2 inhibition in astrocytes increased inflammation and upregulated immune-associated genes and signaling pathways. NDRG2 knockdown induced TNFα expression and secretion via c-Jun phosphorylation. Conclusions: We revealed that under OGD conditions, lactate plays an important anti-inflammatory role and inhibits TNFα expression by stabilizing NDRG2, which is beneficial for neurological functional recovery. NDRG2 may be a new therapeutic target for cerebral ischemia. [ABSTRACT FROM AUTHOR]

ABSTRACT Objective Methods Results Conclusion Implications for the Profession and/or Patient Care Conduct a systematic review of existing studies on intrinsic capacity (IC) and a meta‐analysis of studies to assess the overall effectiveness of ICOPE in improving IC in older adults.Ten databases were systematically searched from inception to November 8, 2023, and the search was last updated on January 2, 2024. Randomised controlled trials (RCTs) were included. The main outcomes were IC (cognition, psychological, sensory, vitality and locomotion).The results showed ICOPE had a significant effect in improving cognitive function (SMD = 0.36; 95% CI, 0.17 to 0.56, p < 0.001, 12 RCTs, 7926 participants) and depressive symptoms (SMD = −0.70; 95% CI, −0.96 to −0.43, p < 0.001, 26 RCTs, 11,034 participants), but there was no statistically significant difference in improving locomotion (SMD = 0.16; 95% CI, −0.03 to 0.34, p = 0.098, 3 RCTs, 1580 participants). Meta‐regression analysis shows that intervention duration should be paid attention to when the source of heterogeneity is discussed on the cognition.The results suggest that ICOPE may be a potentially effective approach to help improve the IC in older adults, showing significant potential for improving cognitive function and reducing depressive symptoms in particular.ICOPE is expected to provide effective strategies to enhance issues such as IC and may be an innovative way to improve the overall health of older adults. This result provides strong support for geriatric nursing practice and encourages the adoption of ICOPE as a viable nursing approach to promote healthy ageing. [ABSTRACT FROM AUTHOR]

The awareness of the impact of high temperatures on rock properties is essential to the design of deep geotechnical applications. The purpose of this research is to assess the influence of heating and cooling treatments on the physical and mechanical properties of Egyptian granodiorite as a degrading factor. The samples were heated to various temperatures (200, 400, 600, and 800 °C) and then cooled at different rates, either slowly cooled in the oven and air or quickly cooled in water. The porosity, water absorption, P-wave velocity, tensile strength, failure mode, and associated microstructural alterations due to thermal effect have been studied. The study revealed that the granodiorite has a slight drop in tensile strength, up to 400 °C, for slow cooling routes and that most of the physical attributes are comparable to natural rock. Despite this, granodiorite thermal deterioration is substantially higher for quick cooling than for slow cooling. Between 400:600 °C is 'the transitional stage', where the physical and mechanical characteristics degraded exponentially for all cooling pathways. Independent of the cooling method, the granodiorite showed a ductile failure mode associated with reduced peak tensile strengths. Additionally, the microstructure altered from predominantly intergranular cracking to more trans-granular cracking at 600 °C. The integrity of the granodiorite structure was compromised at 800 °C, the physical parameters deteriorated, and the rock tensile strength was negligible. In this research, the temperatures of 400, 600, and 800 °C were remarked to be typical of three divergent phases of granodiorite mechanical and physical properties evolution. Furthermore, 400 °C could be considered as the threshold limit for Egyptian granodiorite physical and mechanical properties for typical thermal underground applications. [ABSTRACT FROM AUTHOR]

An amendment to this paper has been published and can be accessed via the original article. [ABSTRACT FROM AUTHOR]

Cemented paste backfill (CPB) is widely used in underground mining, and attracts more attention these years as it can reduce mining waste and avoid environmental pollution. Normally, to evaluate the functionality of CPB, the compressive strength (UCS) is necessary work, which is also time and money consuming. To address this issue, seven machine learning models were applied and evaluated in this study, in order to predict the UCS of CPB. In the laboratory, a series of tests were performed, and the dataset was constructed considering five key influencing variables, such as the tailings to cement ratio, curing time, solids to cement ratio, fine sand percentage and cement types. The results show that different variables have various effects on the strength of CPB. The optimum models for predicting the UCS of CPB are a support vector machine (SVM), decision tree (DT), random forest (RF) and back-propagation neural network (BPNN), which means that these models can be directly applied for UCS prediction in future work. Furthermore, the intelligent model reveals that the tailings to cement ratio has the most important influence on the strength of CPB. This research can boost CPB application in the field, and guide the artificial intelligence application in future mining. [ABSTRACT FROM AUTHOR]

• The two-constituent model and multiscale structure model were established. • Fracture toughness of mineralogical compositions were investigated by using nanoindentation. • The mineral-mechanical statistical method and the upscaling method were proposed. The widespread occurrence of heterogeneous mudstone poses several challenges for the stability of engineering structures. To understand the failure mechanism of argillaceous projects, and reveal the heterogeneity of mudstone, the mechanical properties of mineralogical compositions in mudstone were investigated, by using the nanoindentation technique at the meso -scale. Through "X-ray diffraction (XRD), scanning electron microscope (SEM)- energy dispersive spectrometer (EDS), and mercury intrusion porosimeter (MIP)" observations, the mineralogical compositions in mudstone can be divided into two constituents: clay matrix and silt inclusions, further, the multiscale structure model of mudstone includes three scales: macro-, meso- and micro-scale. Nanoindentation technique was adopted to investigate the meso -scale mechanical properties of mudstone by setting four peak loads ranging from 1 mN to 30 mN on different positions to avoid measuring errors. A superposition of 2 Gaussian probability densities was used to represent the distributions of the mechanical parameters of the mudstone by applying a coupled mineral-mechanical approach proposed in this study. The results showed that the mean hardness and elastic modulus of clay matrix are 398.22 MPa and 11.89 GPa, which are much smaller than that of silt inclusions (1529.43 MPa and 22.08 GPa) in mudstone, inducing the soft properties of mudstone and argillaceous projects. Due to the influence of macro- and meso -scale pores and cracks in mudstone, the elastic modulus of both the clay matrix and silt inclusions in it, is larger than that of mudstone. [ABSTRACT FROM AUTHOR]

• Dance intervention may reduce the presence and severity of frailty in older adults. • According to the frailty criteria, dance intervention reduced the prevalence of slowness, weakness, and low physical activity. • Dance is a popular recreational activity and can be promoted as preventive strategies for frailty. The aims of this study were to examine the effects of dance intervention on frailty in pre-frail and frail older persons. This is a quasi-experimental, two-group trial. Older adults living nursing home. Participants aged ≥ 60 years with low physical activity (mean age was 81.8 years; 71 % were female) (N = 66). Participants allocated to the dance group attended 40 min dance sessions in a nursing home, three times a week for 12-weeks. Participants allocated to the control group maintained their normal daily activities. Assessments were conducted at baseline, 6 weeks, and 12 weeks by researchers blinded to the allocation. Frailty was measured based on Fried criteria. Estimates of frailty between groups over time were calculated using the generalized estimating equations (GEE) and mixed effects models. The prevalence of frailty decreased over time in the dance group compared to the control group (P = 0.002). The mean frailty scores decreased 0.69 at 6 weeks and 1.06 at 12 weeks. Compared to the control group, the prevalence of slowness (p = 0.002), weakness (p = 0.005), and low physical activity (p < 0.001) significantly decreased in the dance group. Dance intervention may reduce the presence and severity of frailty in older adults. Slowness and low physical activity improve following 12 weeks of dance intervention. [ABSTRACT FROM AUTHOR]