Study on surrounding rock failure characteristics and control technology of gob-side entry retaining in"three hard" thin coal seam

This study aims to address existing problems of complex stress conditions and difficulties in retaining roadway so as to achieve long-term stability of roadway surrounding rock in gob-side entry in thin coal seam. Specifically, we investigated the 4301 working face of Liangshuijing Coal Mine in Huisen Coal Industry of Shaanxi Province through theoretical analysis, numerical simulation and engineering practice, with an aim to study the failure characteristics and control countermeasures of surrounding rock of gob-side entry retaining in shallow buried "triple hard" thin coal seam, and analyse the influence of structural parameters of roadside support on roadway stability. The results show that 1)maintaining the roadway through roadside filling body requires sufficient support strength and appropriate shrinkage to the roof and ensuring the overall stability of the roadway; 2)the mechanical behaviour of high water filling material under uniaxial compression can be divided into four stages: "uniform compaction, elastic deformation, dynamic instability and deterioration failure". The numerical simulation results show that in increasing the width of the filling body, the maximum stress first increases, then decreases and then increases, and a stable bearing stress core appears at 1.6 m. Theoretical calculation shows that the optimal height of roof cutting is 10.7 m, and it offers the roof cutting scheme and parameters of shaped blasting. Engineering practice shows that there is no large deformation and no obvious stress concentration in the 60 m range behind the working face. The surrounding rock exhibits good overall control effect and stable structure, and the effect of retaining roadway meets the design requirements

Inherited disorders of complex lipid metabolism: A clinical review

Over 80 human diseases have been attributed to defects in complex lipid metabolism. A majority of them have been reported recently in the setting of rapid advances in genomic technology and their increased use in clinical settings. Lipids are ubiquitous in human biology and play roles in many cellular and intercellular processes. While inborn errors in lipid metabolism can affect every organ system with many examples of genetic heterogeneity and pleiotropy, the clinical manifestations of many of these disorders can be explained based on the disruption of the metabolic pathway involved. In this review, we will discuss the physiological function of major pathways in complex lipid metabolism, including nonlysosomal sphingolipid metabolism, acylceramide metabolism, de novo phospholipid synthesis, phospholipid remodeling, phosphatidylinositol metabolism, mitochondrial cardiolipin synthesis and remodeling, and ether lipid metabolism as well as common clinical phenotypes associated with each

A Nonlinear Constitutive Model for Remoulded Fine-Grained Materials Used under the Qinghai–Tibet Railway Line

Using undrained triaxial shear tests, this study investigates the mechanical properties of fine-grained materials (silty clay and sand) which are extensively used for China’s Qinghai–Tibet Railway (QTR) under different confining pressures (σ3) and freezing temperatures (T). The results show that a reduction in T causes an increase in the shear strength and elastic modulus of all the materials tested in the present study. In addition, the freezing of the silty clay has no significant effect on the type of soil behaviour (strain-hardening), whereas the freezing of the sand changes its strain-hardening behaviour to strain-softening. Supposing that the deviatoric stress–strain curves of the silty clay and sand can be divided into two segments due to a reverse bending point, it was assumed that the first segment follows a hyperbolic function. Meanwhile, the second segment is also a hyperbola, with the reverse bending point as the origin and the residual strength as the asymptote. Accordingly, a nonlinear relation constitutive model that considers σ3 and T is derived. All model parameters are identified. The reasonability of the new model was verified using the test results of the materials. A comparison of the predicted and test results shows that this model can well simulate the deviatoric stress–strain response in the failure process of the tested materials. In particular, it can reflect the residual deviatoric stress after the materials’ failure

Genomic Diagnoses for Ectopic Intracerebral Calcifications.

BACKGROUND AND OBJECTIVES: Ectopic intracerebral calcifications (EICs) in the basal ganglia, thalamus, cerebellum, or white matter are seen in a variety of disease states or may be found incidentally on brain imaging. The clinical significance and proportion of cases attributable to an underlying genetic cause is unknown. METHODS: This retrospective cohort study details the clinical, imaging, and genomic findings of 44 patients with EICs who had no established diagnosis despite extensive medical workup. RESULTS: In total, 15 of 44 patients received a diagnosis through genomic testing explaining their calcifications, and 2 more received a diagnosis that has not been previously associated with EICs. Six of the 15 were found to have one of the 4 genes (PDGFB, PDGFRB, SLC20A2, and XPR1) conventionally associated with the phenotypic term idiopathic basal ganglia calcifications. DISCUSSION: These findings support the use of genomic testing for symptomatic patients with EICs

Molecular insights into the formation of drug-polymer inclusion complex

Drug-polymer inclusion complex (IC) has been viewed as a novel solid form of drugs for property modification. Nonetheless, our understanding of the formation mechanism remains limited. This work aims to provide insight into the molecular processes governing the structural construction of carbamazepine (CBZ) and griseofulvin (GSF) channel-type ICs in the presence of guest polymers. Leveraging microdroplet melt crystallization, we successfully unveiled the single-crystal structures of these ICs, enabling theoretical analysis. Our investigation, which encompasses structural analysis, density functional theory calculations, and molecular dynamics (MD) simulations, elucidates the disparity between CBZ and GSF channels in terms of their autonomy in the absence of guest polymers. CBZ molecules can spontaneously assemble into stable channel structures independently, capitalizing on their unique mortise-tenon architecture and robust π...π interactions. In contrast, GSF channels lack sufficient support from weak Cl...O and C-H...π intermolecular interactions and necessitate the insertion of guest molecules to stabilize their structures. Regardless of the structural reliance on guest polymers, channel size is determined by the size, shape, and conformation of the host molecules, as well as intermolecular interactions. Interestingly, while the eleven structurally determined drug-polymer ICs adopt diverse approaches to construct channel structures, their channel sizes consistently fall within a narrow range of 3.86-5.18 Å, slightly larger than the radial diameter of the guest polymers (2.83-3.50 Å). Consequently, we propose that a crucial prerequisite for the formation of drug-polymer ICs is that the host molecules have the capacity to self-assemble into a porous structure with accommodating channels for guest polymers. Additionally, our results confirm the efficacy of microdroplet melt crystallization in rapidly synthesizing drug-polymer ICs and cultivating their single crystals of high quality and sufficient size. This achievement overcomes the challenges associated with structure elucidation and promises to promote further research into the formation mechanism of drug-polymer ICs. We anticipate that these findings will inspire continued exploration of this novel solid form, facilitating theoretical predictions and practical applications in pharmaceutical development

Functional promoter -308G>A variant in tumor necrosis factor α gene is associated with risk and progression of gastric cancer in a Chinese population.

BACKGROUND: Tumor necrosis factor-α (TNF-α) plays a crucial role in the development and progression of gastric cancer. A functional polymorphism, -308 G>A (rs1800629), which is located in the promoter of TNFA gene, has been suggested to alter the production of TNF-α and influence cancer risk. In the present study, we sought to investigate whether this polymorphism has effects on the risk and progression of gastric cancer in a Chinese population. METHODS: We genotyped the TNFA -308 G>A polymorphism using the TaqMan method in a two-stage case-control study comprising a total of 1686 gastric cancer patients and 1895 cancer-free subjects. The logistic regression was used to assess the genetic associations with occurrence and progression of gastric cancer. RESULTS: We found a significant association between the variant genotypes and increased risk of gastric cancer [P = 0.034, odds ratio (OR) = 1.39, 95% confidence interval (CI) = 1.01-1.67, GA/AA vs. GG]. Similar results were observed in the follow-up replication study. When combined the data from the two studies, we found a more significant association (P = 0.001, OR = 1.34, 95%CI = 1.13-1.59), especially for older subjects (>65 years). Furthermore, the patients carrying the variant genotypes had a significantly greater prevalence of T4 stage of disease (P = 0.001, OR = 2.19, 95%CI = 1.39-3.47) and distant metastasis (P = 0.013, OR = 1.61, 95%CI = 1.10-2.35). CONCLUSIONS: Our results suggest that the functional promoter -308 G>A polymorphism in TNFA influence the susceptibility and progression of gastric cancer in the Chinese population

Polymer Stabilized Liquid Crystal Smart Window with Flexible Substrates Based on Low-Temperature Treatment of Polyamide Acid Technology

Polymer stabilized liquid crystal (PSLC) devices can be used as smart privacy windows that switch between transparent and opaque states. The polyimide alignment layer of a PSLC device is usually obtained by the treatment of polyamide acid (PAA) with temperatures over 200 °C. This hinders the fabrication of PSLC devices on flexible substrates, which melt at these high temperatures. In this work, the fabrication of a PSLC alignment layer using a lower temperature that is compatible with most flexible substrates, is demonstrated. It was found that the treatment of PAA at 150 °C could generate the same alignment for liquid crystals. Based on this, a PSLC device was successfully fabricated on a flexible polyethylene terephthalate (PET) substrate, demonstrating excellent electro-optic performances