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Coal and gas outburst is tightly related to the existence of tectonic coal. Because large blocks of tectonic coals are difficult to be collected, reconstituted coal specimens are often used to study the mechanical properties. In this study, reconstituted coal specimens were prepared under different external forces. Then, triaxial compression tests were conducted under different confining pressures. The deviatoric stress, volumetric strain, axial strain and dilatancy ratio were analyzed. From the laboratory tests, the cohesion of reconstituted coal is positively related to the applied external force. Bonds are developed between coal particles. It is found that the deviatoric stress mainly contributes to bond breakage and internal friction. Under low confining pressure testing condition, the specimen is in over-consolidation state. The failure process is similar to the failure of intact coal. The deviatoric stress reaches the peak value. Then a strain-softening effect is observed with the bond breakage. But for normal consolidation scenario, the bond-breakage stress is smaller than the maximum internal friction force. With the increase of deviatoric stress, the shear stress exceeds the threshold limit value of bond breakage first and then, it exceeds the maximum internal force. Before the new unstable fracture development, extensive bond breakage happens. When the shear stress exceeds the maximum friction force, internal slippage occurs with sharp increases of dilatancy ratio. From this study, the failure behaviors of reconstituted coal are closely related to the stress conditions. The understanding of tectonic coal failure process is enhanced.

We study the impact of formal and informal institutions perceived and experienced by firms on their innovation using the 2012 World Bank Enterprise Survey data in China. We propose a framework to identify different innovator types of firms. Our analysis shows that (1) perceived constraints from the governmental system make firms more likely to be innovators than non-innovators; (2) perceived constraints from the legal system make firms more likely to be imitators than innovators; (3) lack of formal finance makes firms more likely to be non-innovators than innovators; (4) prevalence of bribery makes firms more likely to be non-innovators than innovators but less likely to be innovation pretenders than innovators. Our study enriches institutional theory and innovation research by establishing a framework that encompasses multiple dimensions of formal and informal institutions perceived and experienced by firms and the impacts of such perception and experience on firms’ propensity to become certain type of innovator.

The fragmentation of coal produces abundant coal gases and is presumed to be the defining characteristic of coal and gas outbursts. Knowing the mechanism of these catastrophic hazards is one of the most important breakthroughs in mining geology. In the outburst process, coal spallation represents a unique failure type and typically leaves behind a spallation area (with a series of fracture textures) in the coal seam. Revealing its features and formation mechanism is crucial in accurately interpreting the outburst process. In this study, we conducted a series of outburst experiments with different gases, including CO2, N2, and He. We establish that a spallation area can develop spontaneously during CO2 and N2 tests, whereas an outburst caused by He tests (even under stressed conditions) does not produce a spallation area. That is, the spallation area cannot be observed in non-absorbable gas outbursts. We, therefore, focus on the role of coal gas in spallation and propose a viable mechanism to explain its formation. During the outburst development stage, the influence of gas ad-/desorption is critical, as it controls the width of the spallation area and the spallation thickness. In contrast, stress is not a necessary condition. Whether a spallation area will be produced is particularly determined by the generation of a sufficient internal pressure gradient. Moreover, because of gas desorption, the total outburst energy can be increased by 1.84–5.30 times; and the mean outburst propagation velocity and the mean frequency of coal spallation ejected can be enhanced by 0.38–8.76% and 1.28–12.07%, respectively. Consequently, the destructiveness of outbursts depends on the contribution of desorbed gas.

This research reviewed the mechanics and gas desorption properties of intact coal, and tested the crushing work ratios of different intact coals, and then, studied the stress conditions for the failure or crushing of intact coal and the gas demand for the pulverization of intact coal particles. When a real-life outburst case is examined, the required minimum stress for intact coal outburst is estimated. The study concludes that the crushing work ratios of three intact coal samples vary from 294.3732 to 945.8048 J/m2. For the real-life case, more than 2300 MJ of transport work is needed, and 10062.09, 7046.57 and 5895.47 m3 of gas is required when the gas pressure is 1, 2 and 3 MPa, respectively. The crushing work exceeds the transport work and even reaches 13.96 times of the transport work. How to provide such an enormous crushing work is an energy-limiting factor for the outburst in intact coal. The strain energy is needed for the crushing work, and the required minimum stress is over 54.35 MPa, even reaching 300.44 MPa. These minimum stresses far exceed the in-situ vertical and horizontal stresses that can be provided at the 300–700 m mining depth range.

In the future, suicide risk prediction and management should be transformed from psychiatrist’s judgment (mental illness-like symptoms) into modern technique-guided diagnostics and target drug therapeutics in larger clinical settings. To embrace modern scientific and technological advances, a number of unique diagnostic and therapeutic approaches must be established. This Article provides some important ideas and mechanisms proposed by translational programs.

CO2 geo-sequestration in unminable coal seams is one promising method to mitigate greenhouse gas emissions and would be a means of cleaner production. At the same time, the injected CO2 can enhance coalbed methane recovery and offsets the economic cost for CO2 transportation and injection. However, this technology is still at its primary stage and so far, no large scale of field CO2 injection has been implemented. One of the main difficulties encountered in this process is the permeability reduction induced by CO2 injection and as a result, the injection rate is sharply dropped in the later period. In this paper, detailed laboratory experiments are conducted to investigate the permeability reduction effects during CO2 injections. The dynamic permeability reduction effects are measured with the continuous CO2 injection under different confining pressure conditions. Permeability reduction effects of 13 %–77 % are obtained with respect to the CO2 exposure time in different testings. In low permeability scenario, the permeability reduction effects are severer. Specifically, when the absolute permeability is 1mD, 0.42mD, 0.18mD and 0.03mD, the permeability reduction is 13 %, 36 %, 48 % and 77 %, respectively. Compared with the coal triaxial adsorption tests, it is suggested that the permeability equilibrium is not equal to the adsorption equilibrium. The triaxial adsorption equilibrium process takes much longer time than that of permeability equilibrium process. Based on the testing results, a novel dynamic permeability model is proposed to illustrate the permeability evolutions. The existence of weak internal surface influences the matrix strain and the permeability. This model is also validated by other’s experimental results and can be used for explaining coal seam permeability reduction effects of CO2 injection in coal seams.

BACKGROUND In general, atlantoaxial dislocation is rare due to the stability of the C1-C2 complex. Traumatic atlantoaxial dislocations are usually anterior and accompanied by odontoid fractures. Posterior atlantoaxial dislocations are rare, and complete posterior dislocation without associated fracture is even more rare. A case of early recurrence of posterior atlantoaxial dislocation without fracture being in therapy of first closed reduction and then open reduction has not been previously reported. CASE SUMMARY A 45-year-old female presented with traumatic posterior atlantoaxial dislocation (TPAD) of C1-C2 without associated fractures, and Frankel Grade B spinal cord function. She was successfully managed by immediate closed reduction under skull traction. Unexpectedly, 17 d later, re-dislocation was discovered. On day 28, closed reduction was performed as before but failed. Then, open reduction and posterior internal fixation with autologous iliac bone grafts was performed. By 6 mo after surgery, atlantoaxial joint fusion was achieved, and neurological function had recovered to Frankel Grade E. At 12 mo follow-up, she had lost only 15° of cervical rotation, and atlantoaxial complex instability in joint flexing and extending were no longer observed under fluoroscopy. CONCLUSION Early assessment of transverse ligament is critical for TPAD without fracture avoiding re-dislocation after closed reduction.

Outburst energy is a major factor influencing coal and gas outbursts, albeit its estimation is difficult owing to the lack of amenable means for quantification of gas desorption. In the past decades, determining the mechanism of outbursts is one of the most challenging issues in rock mechanics. In this study, a triaxial coal and gas outburst simulation system was employed to perform simulated experiments using He (to rule out the influence from gas ad-desorption), N2, and CO2. This facilitated understanding of the energy principle underlying the said outbursts and evaluation of the effects of gas desorption on outburst development. Results of this study indicate that outburst energy and energy consumption are influenced by several factors, including outburst pressure, outburst intensity, ejection distance, and particle size of ejected coal. Among these, gas desorption demonstrates the greatest influence when performing controlled tests (using He). Considering the effects of gas desorption, the total outburst energy can be increased by 1.35–2.95 times, thereby causing an enormous increase in the destructive potential of outbursts. Additionally, values of the coal crushing and transport energies can be enhanced by the order of 118.9–206.6% and 157.8–406.6%, respectively, thereby resulting in a stronger conveying capacity of outburst coal–gas flow along with severe coal fragmentation. A further analysis of the energy distribution indicated that in the development stage, gas desorbed from coal acts as the force driving coal transport, whereas free gas energy is mainly consumed during coal crushing. Findings of this study highlight the importance of quantifying contributions of coal gas towards effective interpretation of outburst-causing mechanisms.

Deep mining and drilling activities typically trigger significant deformation of coal/rock roadway and even coal/rock dynamic hazards, which has attracted considerable attention. Hence, in this article, the mechanics and failure properties of intact coal are examined through triaxial compression tests and creep tests. First of all, triaxial compression experiments demonstrated that the complete stress–strain curves of intact coal are characterised by Class-I behaviour; and the post-peak modulus is negative. Second, with increasing confining pressure, peak strength and residual strength rise linearly, whereas elasticity modulus and peak strain increase as a power function form. Thirdly, compared with conventional triaxial load, tiered cyclic load can stiffen the strength of intact coal. Moreover, the data of creep tests are successfully fitted to the Burgers model. Maxwell elasticity modulus is significantly smaller than other creep parameters; Maxwell viscosity coefficient shows a positive correlation with deviatoric stress. Contrarily, Kelvin elasticity modulus and Kelvin viscosity coefficient drop with the rise in deviatoric stress. Additionally, with increasing deviatoric stress, single-step creep strain and average creep strain rate, proposed in this study, increase in a power function form. Finally, failure characteristics of intact coal under triaxial stress could be classified into four types (mainly shear failure and multiple shear fractures). The failure-plane angle generally linearly increases with the rise in confining pressure applied.

PurposeThis paper aims to study how state ownership influences the innovation process in terms of allocating resources toward searching for new solutions and converting these efforts into economic value. On one hand, deep pockets of the state provide slack resources that may facilitate risk taking and innovation. On the other hand, soft budgets can create incentive problems and dampen the efficient use of resources. The authors suggest how accounting for competitive context can disentangle these countervailing forces.Design/methodology/approachThe authors use a panel of over 240,000 Chinese firms over the years 2004–2008. The broad sample and period afforded substantial variability in terms of state ownership within and across firms. The authors use a two-stage model and a within-firm (i.e. fixed-effects) design, controlling for all time-invariant firm characteristics and the problematic unobserved heterogeneity that can often lead to erroneous inferences. Furthermore, the relatively short window limits the likelihood of time-varying unobserved firm characteristics biasing the empirical results.FindingsThe authors found that private-sector competition has the opposite effect on the relationship between state ownership and the second step of the innovation process. In industries where there is robust private-sector competition, state ownership diminishes the firm’s ability to convert R&D efforts into economic value. Private-sector competition competes away any advantages state-owned firms may have in terms of developing or accessing the complementary resources needed for commercialization. Ultimately, the inefficiencies of state ownership in terms of relatively undisciplined selection and monitoring of R&D activities outweigh any potential resource advantages derived from state ownership.Originality/valueThe state remains a prominent player in many economies throughout the world. The authors explored how state ownership of firms influences the resources they expend in searching out new solutions, and their success in converting such resources into economically valuable new products and services. State ownership has potentially countervailing effects on innovation. The authors disentangle these countervailing effects through consideration of how accounting for competitive context could determine whether the beneficial effects of state ownership dominate its detrimental effects for both searching for new solutions and converting these efforts into economically valuable new products. With a focus of market competition as an external force that drives the difference in innovation between SOEs and the private-sector, this study serves as a parallel effort to Jiaet al.(2019) who investigate the joint effect of public and corporate governance on SOEs’ innovation performance, and Zhouet al.(2017) who concern the balance of the institution and efficiency logics on the comparative advantage of SOEs over privately owned enterprises in innovation performance.

The intrinsic exothermic reaction of coal with oxygen during low-temperature oxidation is the main heat source responsible for the self-heating and spontaneous combustion of coal. Due to the comple...

Cancer treatments become more effective now. One cause of these therapeutic promotions is based on drug selective paradigms in the clinic. A small range of drug selective paradigms (pharmacogenomics, precision-oncology, biomarkers and drug sensitivity testing) have been widely used worldwide. To accelerate the performance of these drug selective strategies, improved understanding of different mechanisms may be useful. Among these four classes of selective systems, drug sensitivity testing (DST) plays a unique role in clinical trials. Biomedical advances of knowledge and technology in current drug selective systems are increasingly importance. In the past two decades, knowledge gap between pathology and therapeutics is gradually filling, especially among different predictive mechanisms. The different drug selective systems are competitive, progress and advantageous in different clinical situations. To face with this diversity of drug selective strategies, guiding principle and technical feasibility need to emphasize. As a powerful platform, DST have some unique characters—high-quality quantification and comparison of responses among anticancer drug of interests. The smooth progress of DST platform depends on increasingly understanding of cancer biology, pathology and pharmacology—including medical knowledge (cancer heterogeneity, plasticity, stem cells and metastasis) and technical versatility (micro-fluidity and apoptotic evaluation). The medical and technical insights into various and uniqueness of DST are especially highlighted in this article.

It is imperative to have an in-depth understanding of CO overrun at the air return corner not only for pre-warning concentrations of safety and spontaneous combustion but also for providing scienti...

Purpose The purpose of this paper is to examine the relationship between working capital management (WCM) and firm performance in the context of the Chinese economy. Specifically, it investigates the effects of ownership structures as an internal factor and of institutional environments (IE) as an external factor shaping this relationship. Design/methodology/approach The study applies two-way fixed effect regression models to a sample of Chinese listed manufacturing firms for the period of 2010 to 2017. WCM is measured by cash conversion cycles (CCC); profitability is measured by core profit ratios; ownership structures are classified based on state-owned enterprises (SOEs) and non-SOEs; and IEs are measured from dimensions of factor markets (FM) and legal systems (LS). Findings First, the results show a negative relationship between CCC and firm performance. Second, the negative relationship between CCC and profitability is significant for non-SOEs but not for SOEs. Third, both the FM and LS strengthen the negative association between CCC and profitability. Fourth, the moderating effect of FMs and LSs is evident for non-SOEs only. The results hold when using alternative measures of WCM and profitability and while controlling for additional variables. Originality/value The current study shows that while WCM has a significant effect on the profitability of Chinese firms, such an effect greatly depends on the ownership structures and IE involved. The results thus offer important implications in helping the Chinese government create better IEs and in allowing manufacturing firms to improve upon their WCM practices.

Solar energy driven cerium dioxide (CeO2) thermochemical cycle based fuel production is considered to be a promising technology that can integrate with a combined cooling, heating and power (CCHP) system owing to the pollution free property and favorable chemical reaction kinetics characteristics. In this study a combined cooling, heating, power and fuel (CCHPF) distributed energy system is devised to improve the energy utilization efficiency and reduce the dependence on conventional fossil fuels. To realize the efficient and cost-effectively operations of the system, a constrained multi-objective optimization problem with aims of maximizing primary energy saving ratio (PESR) and minimizing CO2 emission and energy cost is proposed to search for the optimal operation strategy and schedule. A potent optimization method that capitalizes on the advantages of the non-dominated sorting genetic algorithm-II (NSGA-II) and the random walk with directional exploitation (RWDE) algorithm is developed to solve the proposed optimization problem more effectively. The fuzzy decision making method is tailored to determine the final operation strategies of the CCHPF system from the obtained Pareto front according to the decision maker preferences. Numerical results show that the proposed system realizes the supply-demand balance, the optimal dispatch of the energy and the efficient economic operation. In comparison with existing CCHP systems, the energy utilization efficiency of the developed CCHPF system increases by 0.60% and 17.65%, CO2 emission decreases by 13.79% and 3.77%, as well as economic cost reduces 0.29% and 6.33% on a typical winter and summer days, respectively. The research findings provide new insights for improving the coordinated operation of distributed renewable energy system and alleviating energy crisis and environmental pollution.

The catastrophic failure of coal under super-critical stresses and mining-induced disturbance is becoming one of major safety risks of underground mining. Research of the failure pattern o...

As the fastest growing city in China, Shenzhen, a pioneer of reform and opening up, seems to have exhausted its advantages of geographical convenience, cheap land, and cheap labor, thus, the tourism industry has been adopted as a new economic strategy. However, the Shenzhen tourism market has received little attention from scholars and few studies have been done to investigate the relationships between uncertainty and tourism consumption preferences in different cultures. Therefore, this paper attempts to study Shenzhen as a travel destination to explore the consumption preferences of domestic and international tourists, specify uncertainties in tourism consumption activities, and examine their impacts on preferences. The above aims are achieved using a survey method and a new theoretically proposed preference uncertainty model inspired by combining the modified virtual expert preference approach and the ordered probit model (MVEP-OPM), in which three major components of tourism consumption (food, accommodation, and shopping) are estimated. (1) The results show that there are significant differences in tourism consumption preferences between domestic tourists and international visitors. (2) Inexperience, unfamiliarity, imperfect knowledge, and policy uncertainty are major uncertainties in tourism consumption activities, which affect tourist preferences toward consumption behavior. (3) Uncertainty plays a different moderating role in product-related influential factors, such as sanitation, safety, and decoration.

Past clinical evidence suggests that there is partly an association between suicide risk/mortality and mentally health condition. It is an interesting subject for modern diagnostic implication and therapeutic targeting. As a result, neuropathy in brain and relevant treatment (eased by anti-depressive agents or herbs) can be extensively explored. In order to find useful way for cutting off unnecessary suicide-induced human mortality, mental-related genes or molecules study may move forwards suicide risk prediction, prevention, targeting and application. This perspective highlights emerging areas of human suicide and mental healthcare.

Coal mine fire often occurs in lean-oxygen environments caused by methane. In order to clarify the characteristics and mechanisms of coal-oxygen reaction under these conditions, the coal-oxygen reaction experiments were carried by using thermogravimetric analysis (TGA)-gas chromatograph (GC) combined technology in the range of 30-800°C. The thermogravimetric-subtraction/derivative thermogravimetric-subtraction (TG-S/DTG-S) curves which can more accurately reflect the coal-oxygen process were obtained by subtracting the TG/DTG curve of coal pyrolysis under the condition of pure N2. Through TG-S/DTG-S curves, the coal-oxygen reaction was divided into low temperature oxidation stage, accelerated oxidation stage and combustion stage. In the low temperature oxidation and accelerated oxidation stages, methane delayed the coal-oxygen reaction as an inert gas. Under the same oxygen concentration, the effect of methane on reducing CO, CO2 production and increasing ignition temperature (Ti) of coal was obvious than...

Background:. Nasopharyngeal carcinoma (NPC) is sensitive to radiotherapy (RT). However, neurocognitive complications such as memory loss and learning and attention deficits emerge in the survivors of NPC who received RT. It remains unclear how radiation affects patient brain function. This pilot study aimed at finding cerebral functional alterations in NPC patients who have received RT. Methods:. From September 2014 to December 2016, 42 individuals, including 22 NPC patients and 20 normal volunteer controls in National Cancer Center/National Clinical Research Center for Cancer/Cancer Hospital, Chinese Academy of Medical Sciences, and Peking Union Medical College, were recruited in this study. All patients received resting-state functional magnetic resonance imaging scans and neurocognitive tests 1 day before the initiation of RT (baseline) and 1 day after the completion of RT; the 20 normal controls were also subjected to the same scans and tests. The amplitude of the low-frequency fluctuations (ALFF) in blood oxygen level-dependent signals and functional connectivity (FC) were used to characterize cerebral functional changes. Independent t test, paired t test, and analysis of variances were used to obtain statistical significance across groups. Results:. After RT, NPC patients showed significantly decreased ALFF values in the calcarine sulcus, lingual gyrus, cuneus, and superior occipital gyrus and showed significantly reduced FC mainly in the default mode network (P

Coal and gas outbursts are small-scale geological disasters controlled by tectonic movement, and tectonic coal is widespread in outburst zones. In this study, we compare tectonic and intact coal specimens to examine the basic properties of tectonic coal. We estimate the different energies and limits of the crushing work ratio of coal from five typical outburst cases using on-site outburst data, and discuss the relationship between outbursts and tectonic coal. The results show that tectonic coal is a product of tectonic movement and its original primary structure is destroyed during the tectonic process. Compared with intact coal, tectonic coal shows low strength properties and a crushing work ratio of 22.11 J/m2. The specific surface area and total pore volume of the minipores, mesopores, and macropores of the coal strongly increase under conditions of intense tectonism, which indicates that tectonic coal has a very high capacity for rapid initial gas desorption. An adequate supply of gas is required to transport outburst coal, such that the existence of coal particles smaller than the critical diameter is important. Our calculations indicate that the crushing work ratio of coal from the five outburst case ranges from 22.19 to 78.67 J/m2. Only the crushing work ratio of tectonic coal satisfies the requirement for these cases. Therefore, the properties of the tectonic coal and crushing work ratio for the five cases indicate that the widespread occurrence of tectonic coal plays a crucial role in outbursts.

Respirable dust pollution at an underground heading face driven with continuous miner was detected during a ventilation survey. In order to obtain fundamental understandings of the airflow patterns and the respirable dust dispersion characteristics within the heading face, three dimensional Computational Fluid Dynamics (CFD) models were developed according to field condition. The continuous miner (JOY 12CM27), which significantly impacts the ventilation and respirable dust flow behaviour, was embedded into the model. The inappropriate ventilation arrangement, lack of effective dust control measures, as well as insufficient maintenance of equipment (e.g. blunt picks, missing nozzles etc.) were identified as the main reasons causing the high dust exposure levels (greater than 500 mg/m3). Based on the CFD model results, a new ventilation arrangement together with dust mitigation strategy were proposed. And an evaluation of the proposed system demonstrated a high respirable dust mitigation effect (90%) could be achieved. Therefore, it is highly recommended these control strategies to be implemented immediately to address the extremely high dust levels in the underground working environment. The proposed strategy will be also suitable for headings with similar conditions and could provide guidance for mining operators to refer.

Purpose This paper aims to investigate the Chinese employment relationship under the framework of psychological contracts. The authors explored the effects of firm ownership (in terms of state-owned and private enterprises) and employment type (in terms of permanent and temporary employees) on employee perceptions of psychological contract. In addition, the associations between fulfilled psychological contract and various dimensions of employee attitudes were examined. Design/methodology/approach The authors adopted a questionnaire as the primary instrument to investigate the impact of firm ownership and employment type on psychological contract perceptions and outcomes. The analysis was based on a Chinese sample of a size of 363 employees. Findings The results indicate that state-owned employees overall reported fewer promises (employer under-obligation promised psychological contract), while private employees tended to have more promises (mutual high obligation, employer over-obligation and quasi-spot obligation promise-based psychological contract). Permanent employees reported high fulfillment (employer over-obligation, mutual high obligation and employer under-obligation fulfilled psychological contract). In contrast, temporary employees presented many promises (mutual high obligation promised psychological contract) and low fulfillment (quasi-spot fulfilled psychological contract). In general, firm ownership had weak effects on permanent and temporary employees’ perceptions of promise-based psychological contract, but no significant influence on fulfillment-based psychological contract. Moreover, psychological contract fulfillment was positively related to employees’ fairness perception and job satisfaction, while negatively related to the intention to quit. The authors failed to find comprehensive statistical support for the moderating effects of firm ownership or employment type. Originality/value The study contributes to the literature through a number of ways. First, instead of psychological contract breach, the authors use psychological contract fulfillment as a direct measure to examine the relationship between psychological contract and employees’ attitudes. Second, they investigate the effects of firm ownership on employment relationship under the psychological contract framework, enriching the institutional lens of the issue. Third, while majority of psychological contract studies concerning employment type concentrate on either permanent or temporary employees, the authors take both types into account. Fourth, they integrate perspectives of firm ownership and employment type. Finally, the authors perform the study in the Chinese context, which offers extra evidence to the body of psychological contract literature.

Spontaneous combustion of coal has long been a thermal dynamic hazard during coal mining, storage, and transport, posing a great threat to coal mine safety. Especially coal spontaneous combustion in longwall goaf poses a great threat to underground working crew. To investigate such a mine safety issue with more insights and “what if” scenarios, this study employs CFD technique to develop a proactive inertisation plan in a longwall goaf. Based on real on-site conditions of the longwall goaf, a three-dimensional transient non-equilibrium thermal CFD model was developed to study heating evolution and proactive inertisation plans of the longwall goaf. The theoretical model incorporated a set of governing equations including low temperature kinetics of coal oxidation, energy and mass conservation, momentum balance, and continuity equation. After the base model (1000 m) was validated and calibrated with field gas monitoring data, another model (500 m model) was studied to obtain an optimum inertisation plan. Both steady state and transient simulations were conducted to study the flow dynamics of air velocity, oxygen ingress, dispersion of gaseous products and heating evolution in the longwall goaf. Based on the flow dynamics field, proactive inertisation plans using nitrogen to suppress the onset and development of goaf heatings were then developed and studied.

Extensive studies have been conducted on the use of fibre-reinforced polymer (FRP) as a confining material in hybrid tubular columns for civil construction, where the design of columns is often controlled by the stiffness and/or strength requirements. By contrast, the capacity of sustaining large deformation without losing structural integrity can be critical in some applications such as the standing supports for underground mines. This paper presents the conceptual development of a novel column form with large deformation capacity. The novel column consists of an outer FRP tube, and an infill made of coarse lumps/aggregates, which can be from coal rejects or other waste/recycled materials, as well as calcium sulfoaluminate (CSA)-based cementitious material with high water content. In addition to its large deformation capacity, the new column allows the extensive, direct and easy use of waste materials and eliminates the need for mixing concrete on site or transporting commercial concrete. This paper also presents the results from a series of compression tests on the new columns as well as two similar column forms. These tests demonstrate the very large deformation capacity of the new column and show that an existing stress-strain model for FRP-confined normal concrete can be used to provide reasonable predictions of the behaviour of the confined infill material in the new column. The potential applications of the new column and the needs for future research are also discussed.

The constant Ebola epidemic outbreaks in Africa arisen in waves of panic worldwide. There is a high mortality rate (30-70%) among the Ebola-infected people in virus- stricken areas. Despite these horrors, the medical capabilities against this deadly viral disease were provided by limited therapeutic agents/options. As a result, several patented agents, biotherapies or prophylactic/therapeutic vaccines need to be reviving into the global markets—including patents of small molecular chemicals, short sequences or oligomers of DNA/RNA, linkages of chemicals with bio-molecules, herbal medicine and so on. In addition, the possible mechanisms of action of these therapeutic options are underway. To promote Ebola biomedical study, the multiple characters of Ebola infections—its origin, pathologic progress, genomic changes, therapeutic context and economic considerations are outlined in this review. Finally, a great difference can be expected after these types of efforts.

Background and aims AIDS (acquired immune deficient syndrome), a deadly human infectious disease is caused by HIV (human immunodeficiency viruses) infection. Patient's mortality was eventually reduced to one-fourth by combined chemotherapy (usually 3 chemical drugs simultaneously) than earlier HIV/AIDS treatments (single drug or vaccine) in the clinic. Results Combined treatments against HIV/AIDS are still incurable for all patients despite a high rate of patient's survival. Basic viral pathological study and advancing drug development systems for curable medications are indispensable nowadays and in the future. Conclusion Up to date, therapeutic trinity (combined therapy) against HIV/AIDS is generally among chemical drugs. In this article, several forms of other therapeutic attempts for effectively curing efforts against HIV/AIDS are proposed-including the development of next generation therapeutic HIV vaccines and schedules, new categories of bio-therapy, different pathways of immune-modulation, herbal medicines in general (allopathic, Ayurveda and traditional Chinese medicines), high quality of physical exercises, and especially therapeutic combinations guided by latest medical discovery and principles (new forms of therapeutic trinity against HIV-induced pathogenesis and human mortality).

Spontaneous combustion of coal in underground coal mine is a long-standing thermal dynamic hazard. The hazard is harmful in diverse aspects: causing loss of coal resource, raising safety concerns, and giving off noxious/greenhouse effect gases. Detection and trending analysis of a few particular gaseous products liberated during coal oxidation is the most fundamental spontaneous combustion forecasting technique in practice. This study mainly reviewed the mechanism and practical knowledge by using such technique to forecast spontaneous combustion. To give more insights in emerging order of fire gas, this study critically reviewed and analysed the detailed production sequences of these key gaseous products. It was indicated production of carbon oxide, hydrogen, methylene and some other hydrocarbon gases can be used to forecast early heating of coal. This study also summarised and discussed the interpretation of the index gases through absolute concentration of key gas indicators and composite ratios. Six common gas monitoring techniques (i.e. tube bundle system, telemetric system, portable system, gas chromatography, infrared spectroscopy, and tunable diode laser adsorption spectroscopy) are discussed in terms of their advantages and limitations in this study. Lastly, a practically demonstrated spontaneous combustion hazard management plan (i.e. TARP) is introduced. TARP uses different gas ratios in various locations to indicate escalating levels of severity of a heating event.

Introduction Suicide is still a major event of human mortality worldwide. Yet human suicide prediction, prevention and therapeutic systems at this moment are generally ineffective in the clinic. No diagnostic system is reliable for significantly suicidal prevention and mortality reduction. As a result, human suicide etiopathologic investigation (especially at genetic/molecular levels in the clinical settings) is quite necessary. In order to boost human suicide researches, emerging human suicide diagnostic/treatment study will be transformed from clinical symptom observations into new generations of candidate drug targets and therapeutics. To achieve this goal, associations between suicidal etiopathologic identification, genetic/bioinformatics-based diagnostics and putative drug targets must be exploited than ever before. After all, the interaction and relationships between environmental/ genetic/molecular clues and overall patient's risk prediction (environmental influences and different therapeutic targets/types) should be found out. Conclusion In the future, effective clinical suicide prediction, prevention and therapeutic systems can be established via scientific expeditions and causality discovery.

Dust management at longwall faces has always been a concern for mine operators. Recent respirable dust monitoring at a longwall top coal caving (LTCC) face indicated that extremely high dust exposure levels have been experienced at the face. Dust contamination from intake ventilation and the incorrect use of ventilation arrangements (i.e. curtains) at maingate (MG) area were identified as the main cause of this issue. Computational Fluid Dynamics (CFD) modelling studies were therefore conducted to investigate the impact of different ventilation arrangements on the dispersion behaviour of respirable dust at the LTCC face, with a special focus on the airflow patterns and the aerodynamics of fugitive dust at the intersection of MG and face. Field investigation was first carried out to observe the dust issue and obtain essential data for the development and validation of base model. Then parametric studies were conducted to evaluate the effectiveness of two different curtain configurations at MG considering the worst scenario of intake dust contamination to face (dust from travel road and beam stage loader (BSL) discharge point flows towards face) with the shearer cutting into the MG. Model results demonstrate that the occurrence of flow separation and incorrect use of curtains account for the main reasons of high dust exposure level at the intersection of MG and face, especially when the shearer is cutting into the MG. Ventilation arrangements at the MG and face entry are critical to minimise the impact of flow separation on the dust flow patterns at the intersection. Based on model results, new ventilation arrangements at the MG and face entry have been proposed and evaluated through which significant dust mitigation effect can be achieved at face entry, contributing to the overall reduction of dust exposure levels along the face.

A new type of wireless passive, high sensitivity, high temperature sensor was designed to meet the real-time temperature test in the harsh aero-engine environment. The sensor consists of a complementary split ring resonator and a substrate integrated circular waveguide (CSRR-SICW) structure and is based on high temperature resistant Si3N4 ceramic as the substrate material. Temperature is measured by real-time monitoring of the resonant frequency of the sensor. In addition, the ambient temperature affects the dielectric constant of the dielectric substrate, and the resonant frequency of the sensor is determined by the dielectric constant, so the function relationship between temperature and resonant frequency can be established. The experimental results show that the resonant frequency of the sensor decreases from 11.3392 GHz to 11.0648 GHz in the range of 50–1000 °C. The sensitivity is 123 kHz/°C and 417 kHz/°C at 50–450 °C and 450–1000 °C, respectively, and the average test sensitivity is 289 kHz/°C. Compared with previously reported high temperature sensors, the average test sensitivity is approximately doubled, and the test sensitivity at 450–1000 °C is approximately three times higher. Therefore, the proposed high sensitivity sensor has promising prospects for high temperature measurement.

The techniques and qualities of drug sensitivity testing (DST) for anticancer treatment have grown rapidly in the past two decades worldwide. Much of DST progress came from advanced systems of technical versatility (faster, highly-throughput, highly-sensitive, and smaller in tumor quantity). As the earliest drug selective system, biomedical knowledge and technical advances for DST are mutually supported. More importantly, many pharmacological controversies are resolved by these technical advances. With this technical stride, the clinical landscape of DST entered into a new phase (>500 samples per testing and extremely low quantity of tumor cells). As a forerunner of the drug selection system, DST awaits a new version that can adapt to complicated therapeutic situations and diverse tumor categories in the clinic. By upholding this goal of pathogenic and therapeutic diversity, DST could eventually cure more cancer patients by establishing high-quality drug selection systems. To smoothen DST development, there is a need to increase the understanding of cancer biology, pathology and pharmacology (cancer heterogeneity, plasticity, metastasis and drug resistance) with well-informative parameters before chemotherapy. In this article, medicinal and technical insights into DST are especially highlighted.

Most of the coal seams in China are characterized by high in-situ stress, high gas pressure, high gas content and low permeability, which makes the gas extraction rather difficult. This infrastructure not only limits CBM production but also presents considerable challenges to the safety and efficiency of coal mining in China.

The form of gas migration in coal seams is either diffusion or seepage, and is closely related to the fracture scale and pore size distribution. However, the characteristic of inhomogeneous pore structure exists in natural coal seams, and has been simplified by some researchers on the basis of the primary and secondary effects of seepage and diffusion in coal seams.

Adsorption is a type of interfacial phenomena, which includes physical adsorption, chemical adsorption and absorption. The gas adsorption in coal belongs to physical adsorption, which means that the gas molecules concentrate in the surface of coal pores, i.e. the gas molecule concentration at the interface between gas and coal is larger than elsewhere. For the physical adsorption, the adsorption force between the solid surface and the gas is the van der Waals force, and the adsorption volume depends mainly on the pressure, temperature and the size of coal surface area. Similar to the gas liquefaction and water vapor condensation, physical adsorption is also reversible. The heat released by gas adsorption is small, and generally, there is about 10–20 kJ of heat released when 1 mol of gas molecules are adsorbed, which is similar to that of gas liquefaction. For the chemical adsorption, chemical bonds are formed between the solid molecule and the gas molecule on the solid surface, i.e. there exists electron exchange between gas molecules and solid surface molecules. The main difference between chemical adsorption and physical adsorption is that the chemical adsorption is irreversible, and the generated heat of chemical adsorption is similar to the thermal effect of chemical reaction, which is generally ten times to several tens of times larger than the physical adsorption heat. A large number of experiments on coal adsorption show that the gas adsorption/desorption in coal is a reversible process and the volume of adsorbed gas is approximately the same as the desorbed gas. The gas adsorption heat measured by experiments ranges from 12.6 to 20.9 kJ/moL, which is approximately equal to the heat released by methane liquefaction.

In view of the problem where there is abnormal continuous CO exceedance in the tailgate corner without any sign of spontaneous combustion associated with the mining of low metamorphic coal seam, both desorption experiments and ambient temperature oxidation experiments were carried out, and the ambient temperature oxidation characteristics and its mechanism were studied. The results demonstrate that the original coal seam from which the experimental coal sample was taken, does not contain CO and CO2, and the coal sample can oxidize at ambient temperature. The O2 consumption rate, CO and CO2 production rate is not directly related to the particle size. Low O2 concentration can inhibit but not eliminate the ambient temperature oxidation. In addition to the active sites of coal itself, the ambient temperature oxidation reaction rate is also affected by the inhibitory substances produced by the reaction itself. R1(△CO/△O2), R2(△CO2/△O2) and R3(△CO/△CO2) indexes are mostly not affected by the changes of particle size, O2 concentration and oxidation rates, and the ambient temperature oxidation of coal is dominated by a single mechanism. The ambient temperature oxidation mechanism is also theoretically deduced. The research will have important significance for controlling the abnormal exceedance of CO.

Moisture, ash content, volatiles, density and hardness of coal. Pore, fracture structures of coal and characterization methods. Coal matrix and its scale features

Curcumin is a natural polyphenol and is supposed to possess antioxidant, anti-inflammatory, anticancer, and antiapoptotic properties. Although some studies have reported the therapeutic effects of curcumin on ulcerative colitis (UC), the specific mechanism remains unclear. An in vitro coculture model of Caco-2 and differentiated THP-1 cells was established. After administration of curcumin (10 μM), Western blot analysis was performed to evaluate the protein levels of tight junction (TJ) proteins zonula occludens- (ZO-) 1 and claudin-1. Annexin V-APC/7-AAD assays and flow cytometry were conducted to assess Caco-2 cell apoptosis. The expression levels of oxidative stress and endoplasmic reticulum stress- (ERS-) related molecules were determined by Western blot analysis. Curcumin administration significantly upregulated ZO-1 and claudin-1 protein levels and reduced Caco-2 cell apoptosis. The protein levels of oxidative stress markers inducible nitric oxide synthase (iNOS) and γH2AX and ERS-induced apoptosis-related molecules C/EBP homologous protein (CHOP) and cleaved caspase-12 were significantly downregulated upon curcumin treatment. Furthermore, curcumin administration greatly blocked the protein kinase-like endoplasmic reticulum kinase- (PERK-) eukaryotic translation initiation factor 2α- (eIF2α-) activating transcription factor 4- (ATF4-) CHOP signaling pathway. Curcumin enhanced intestinal epithelial barrier integrity in the in vitro coculture model by upregulating TJ protein expressions and reducing intestinal epithelial cell apoptosis. The potential mechanisms may be suppression of ERS and subsequent apoptosis.

Gas drainage technologies are the main means of lowering the gas content of coal seams and eliminating the gas hazard of coalmines. As China has a huge reservoir of coalbed methane (CBM) resources, the extraction and utilization of coal seam gas resources can realize the significant triple benefits of ensuring the safe mining of coal resources, promoting the clean and efficient use of coalmine gas, and protecting the environment.

Coal and gas outburst is the extreme instability caused by stress, gas, and coal. In this review article, dominant factors and inducing factors of outburst were summarized; geologic features of typical outburst cases and the effects of tectonic movement on outbursts were analyzed; the outburst stages with considerations to geologic factors were divided. It was found that inducing factors, including buried depth, tectonic movement, gas composition, coal seam conditions, overlying/underlying rock conditions, and mining mode, control the outburst by influencing the dominant factors (stress, gas, and coal). Among them, tectonic movement is the key of outburst. Influenced by tectonic movement, the primary structure of coals is damaged/pulverized due to the tectonic stress and unique tectonic mode, resulting in the formation of tectonic coals. When external dynamic factors are changed, tectonic coals are crucial to outburst control for its evolution of porous structure as well as the unique mechanical behaviors and gas flowing responses. Besides, the preparation stage of outburst includes the tectonic process and mining process. The former one refers to the restructuring process of the original coal-bearing strata by tectonic movement, while the mining process is the prerequisite of outburst and it refers to the disturbance of human mining activities to the initial coal seams. It is suggested that more work is required on geological factors of outburst, and a few research areas are proposed for future research.

Coal strength plays a significant role in various mining related engineering activities, including the evaluation of coal and gas outburst dangers, pillar design, hydraulic fracturing design (involving enhanced gas drainage), coalface support, coal seam CO2 sequestration, and other activities.

Coal formation, including coalification effect, peatization effect, diagenesis effect and metamorphism effect; Metamorphism types and maceral composition of coal; Generation of coal seam gas during coal metamorphism, basic composition of coal seam gas, and the existence forms of adsorbed gas and free gas. Controlling effect of magma intrusion on the coal metamorphism and coal seam gas occurrence.

The basic concept of force in coal mechanics consists of external force and stress. The external force is generated from the outside of coal seam and can be further divided into two types, surface force and body force. Surface force is applied to the coal surface, such as gas pressure, coal support force and the contact forces between different coal blocks. Body force, such as gravity and inertia force, is continuously distributed within the coal and is also called a mass force.

Geostress is the natural stress that has not been disturbed by engineering actions affecting strata. The geostress is also known as the initial stress of the rock mass, absolute stress, or the original rock stress.

Groundwater is the dominant source of freshwater in many countries around the globe, and the deterioration in its quality by contaminants originating from anthropogenic sources raises serious concern. In this study, a scenario where groundwater is contaminated by acid mine drainage (AMD) from mining activities and/or sewage was envisaged, and the performance of a direct contact membrane distillation (DCMD) system was investigated comprehensively for different compositions of the AMD- and sewage-impacted groundwater. Regardless of the composition, MD membrane achieved 98-100% removal of metals and bulk organics, while the removal of the selected micropollutants ranged between 80 and 100%. Effective retention of contaminants by the MD led to their accumulation over time, which affected the hydraulic performance of the MD membrane by reducing the permeate flux by 29-76%. When persulfate (PS)-mediated oxidation process was integrated with the DCMD, degradation of bulk organics (50-71%) and micropollutants (50-100%) by PS reduced their accumulation. Characterisation of the fouling layer revealed the occurrence of membrane scaling that was mainly due to the deposition of iron oxide or oxyhydroxide precipitates. For an identical composition of the AMD- and sewage-impacted groundwater, flux decline was 10% less in PS-assisted DCMD as compared to that in the standalone DCMD. However, this did not prevent the formation of iron oxide scales on MD membrane during the operation of PS-assisted DCMD. This study demonstrates the long-term performance of a standalone and PS-assisted DCMD operated in continuous-flow mode to treat AMD- and sewage-impacted groundwater for the first time.