Association between serum estradiol level and appendicular lean mass index in middle-aged postmenopausal women

BACKGROUND Previous studies investigating the association between loss of estrogen at menopause and skeletal muscle mass came to contradictory conclusions.AIM To evaluate the association between serum estradiol level and appendicular lean mass index in middle-aged postmenopausal women using population-based data.METHODS This study included 673 postmenopausal women,aged 40-59 years,from the National Health and Nutrition Examination Survey between 2013 and 2016.Weighted multivariable linear regression models were used to evaluate the association between serum E2 Level and appendicular lean mass index(ALMI).When non-linear associations were found by using weighted generalized additive model and smooth curve fitting,two-piecewise linear regression models were further applied to examine the threshold effects.RESULTS There was a positive association between serum E2 level and ALMI.Compared to individuals in quartile 1 group,those in other quartiles had higher ALMI levels.An inverted U-shaped curve relationship between serum E2 Level and ALMI was found on performing weighted generalized additive model and smooth curve fitting,and the inflection point was identified as a serum E2 level of 85 pg/mL.CONCLUSION Our results demonstrated an inverted U-shaped curve relationship between serum E2 levels and ALMI in middle-aged postmenopausal women,suggesting that low serum E2 levels play an important in the loss of muscle mass in middleaged postmenopausal women.

Quantitative evaluation of gas hydrate reservoir by AVO attributes analysis based on the Brekhovskikh equation

AVO (Amplitude variation with offset) technology is widely used in gas hydrate research. BSR (Bottom simulating reflector), caused by the huge difference in wave impedance between the hydrate reservoir and the underlying free gas reservoir, is the bottom boundary mark of the hydrate reservoir. Analyzing the AVO attributes of BSR can evaluate hydrate reservoirs. However, the Zoeppritz equation which is the theoretical basis of conventional AVO technology has inherent problems: the Zoeppritz equation does not consider the influence of thin layer thickness on reflection coefficients;the approximation of the Zoeppritz equation assumes that the difference of wave impedance between the two sides of the interface is small. These assumptions are not consistent with the occurrence characteristics of natural gas hydrate. The Brekhovskikh equation, which is more suitable for thin-layer reflection coefficient calculation, is used as the theoretical basis for AVO analysis. The reflection coefficients calculated by the Brekhovskikh equation are complex numbers with phase angles. Therefore, attributes of the reflection coefficient and its phase angle changing with offset are used to analyze the hydrate reservoir's porosity, saturation, and thickness. Finally, the random forest algorithm is used to predict the reservoir porosity, hydrate saturation, and thickness of the hydrate reservoir. In the synthetic data, the inversion results based on the four attributes of the Brekhovskikh equation are better than the conventional inversion results based on the two attributes of Zoeppritz, and the thickness can be accurately predicted. The proposed method also achieves good results in the application of Blake Ridge data. According to the method proposed in this paper, the hydrate reservoir in the area has a high porosity (more than 50%), and a medium saturation (between 10% and 20%). The thickness is mainly between 200m and 300m. It is consistent with the previous results obtained by velocity analysis.

Micro-macro fracture mechanism of heterogeneous granite in percussive drilling

The conventional rotary rock breaking method faces a technical bottleneck in improving the rate of penetration(ROP)in deep hard formations.Percussive drilling is the most potential approach to increase rock-breaking efficiency and ROP.However,the rock-breaking mechanism of percussive drilling is still unclear enough,especially the micro-fracture mechanism of rock under confining pressure(under lateral pressure and hydraulic pressure).In this paper,the impact rock breaking experiments by four kinds of Polycrystalline Diamond Compact(PDC)cutters are carried out using a drop-weight impact testing machine and an acoustic emission(AE)recording system,the influence of parameters such as cutter shape,rake angle,and impact energy on rock-breaking are systematically analyzed.This study includes a numerical simulation to examine the process of crack initiation,propagation,and cuttings formation during the impact process with the consideration of confining pressure.The results show the conicalshaped cutter is the most aggressive with high breaking efficiency.The penetration depth of the cutter is mainly influenced by the impact energy and cutter shape than the rake angle of the cutter.There exists critical impact energy makes the rock breaking efficiency the highest.The critical impact energy is about 40 J when using the conical-shaped cutter with a rake angle of 15°.The rock mainly failed in tensile mode,and the inter-grain crack is the main crack.Hydraulic pressure can inhibit the formation of horizontal cracks,while lateral pressure can inhibit the formation of vertical cracks and reduce the proportion of tensile cracks.The research results can provide some reference and basis for improving the rock-breaking efficiency in deep hard formations.

Single-cell analysis identifies phospholysine phosphohistidine inorganic pyrophosphate phosphatase as a target in ulcerative colitis

BACKGROUND Ulcerative colitis(UC)is a chronic gastrointestinal disorder characterized by inflammation and ulceration,representing a significant predisposition to colorectal cancer.Recent advances in single-cell RNA sequencing(scRNA-seq)technology offer a promising avenue for dissecting the complex cellular interactions and molecular signatures driving UC pathology.AIM To utilize scRNA-seq technology to dissect the complex cellular interactions and molecular signatures that underlie UC pathology.METHODS In this research,we integrated and analyzed the scRNA-seq data from UC patients.Moreover,we conducted mRNA and protein level assays as well as pathology-related staining tests on clinical patient samples.RESULTS In this study,we identified the sustained upregulation of inflammatory response pathways during UC progression,characterized the features of damaged endothelial cells in colitis.Furthermore,we uncovered the downregulation of phospholysine phosphohistidine inorganic pyrophosphate phosphatase(LHPP)has a negative correlation with signal transducer and activator of transcription 3.Significant downregulation of LHPP in UC patient tissues and plasma suggests that LHPP may serve as a potential therapeutic target for UC.This paper highlights the importance of LHPP as a potential key target in UC and unveils its potential role in inflammation regulation.CONCLUSION The findings suggest that LHPP may serve as a potential therapeutic target for UC,emphasizing its importance as a potential key target in UC and unveiling its role in inflammation regulation.

羟考酮缓释剂对ST段抬高心肌梗死患者急诊PCI治疗近期预后的影响

目的探讨羟考酮缓释剂对ST段抬高心肌梗死(STEMI)患者行急诊经皮冠状动脉介入术(PCI)术后近期预后的影响。方法选取2018年3月—2018年9月于河北大学附属医院诊断为STEMI患者102例,将患者按随机数字表法分为羟考酮组和对照组。给予两组患者阿司匹林300 mg口服、替格瑞洛180 mg嚼服及阿托伐他汀20 mg口服治疗基础上,羟考酮组术前30 min内给予盐酸羟考酮缓释片10 mg口服,对照组给予安慰剂。然后行急诊PCI。比较两组患者基线资料、手术前及术后30 d心功能指标及PCI术后30 d主要不良心血管事件等,评估羟考酮缓释片对STEMI急诊PCI近期预后的影响。结果羟考酮组氨基末端脑钠肽前体、左心室舒张末期内径低于对照组(P<0.05),而左心室射血分数高于对照组(P<0.05)。羟考酮组的支架内血栓、心力衰竭、二次手术及主要不良心血管事件发生率低于对照组(P<0.05)。结论应用羟考酮缓释片可改善STEMI行急性PCI患者术后30 d的心功能,降低主要不良心血管事件发生率。

Investigating microstructure of Longmaxi shale in Shizhu area,Sichuan Basin, by optical microscopy, scanning electron microscopy and micro-computed tomography

Microstructure of shale formation is the key to understanding its petrophysical and chemical properties.Optical microscopy, scanning electron microscopy and micro-computed tomography(μ-CT) have been combined for characterization of microstructure of Longmaxi(LMX)shale from Shizhu area, Sichan Basin. The results indicate that laminated LMX shale consists of mineral matrix-rich layers and organic matter(OM)-rich layers at micrometer scale in two and three dimensions. Mineral matrix layers,mainly consisting of interparticle pores and intraplatelet pores, are approximately parallel to the bedding plane.Pyrite-rich layer, mainly containing intercrystalline pores,shows a strong preferred orientation parallel to the bedding plane. OM-rich layer, mainly containing OM pores, seems to be discontinuous. In addition, intercrystalline pores are enriched in some layers, while OM pores are distributed irregularly in matrix layers. This vertical heterogeneity of pore microscopic structures in LMX shale is of great importance to understand its petrophysical and chemical properties.

Yielding and fracture behaviors of coarse-grain/ultrafine-grain heterogeneous-structured copper with transitional interface

Heterogeneous-structured Cu samples composed of coarse-grained(CG) and ultrafine-grained(UFG) domains with a transitional interface were fabricated by friction stir processing, in order to investigate the effect of interface constraint on the yielding and fracture behaviors. Tensile test revealed that the synergetic strengthening induced by elastic/plastic interaction between incompatible domains increases with increasing the area of constraint interface. The strain distribution near interface and the fracture morphology were characterized using digital image correlation technique and scanning electron microscopy, respectively. Fracture dimples preferentially formed at the interface, possibly due to extremely high triaxial stress and strain accumulation near the interface. Surprisingly, the CG domain was fractured by pure shear instead of the expected voids growth caused by tensile stress.

Magnetic susceptibility inversion method with full tensor gradient data using low-temperature SQUIDs

Full tensor magnetic gradient measurements are available nowadays. These are essential for determining magnetization parameters in deep layers. Using full or partial tensor magnetic gradient measurements to determine the subsurface properties, e.g., magnetic susceptibility, is an inverse problem. Inversion using total magnetic intensity data is a traditional way.Because of di culty in obtaining the practical full tensor magnetic gradient data, the corresponding inversion results are not so widely reported. With the development of superconducting quantum interference devices(SQUIDs), we can acquire the full tensor magnetic gradient data through field measurements. In this paper, we study the inverse problem of retrieving magnetic susceptibility with the field data using our designed low-temperature SQUIDs. The solving methodology based on sparse regularization and an alternating directions method of multipliers is established. Numerical and field data experiments are performed to show the feasibility of our algorithm.

Association between calcium supplementation and bone mineral density in children:a systematic review and meta-analysis

Objective:To evaluate the effects of calcium supplementation on bone mineral density in children.Methods:The PubMed,Embase,and Cochrane library were systematically searched.The retrieve inception date was between October 2001 and October 2019.Two reviewers independently performed the data extraction and assessed methodology quality.Studies were limited to randomized clinical trials comparing calcium supplement with a placebo for bone mineral density in children.A meta-analysis was performed to calculate standard mean difference(SMD)and 95%confidence interval(CI).Results:A total of 6 randomized controlled trials involving 408 participants(calcium supplementation group:198;placebo group:210)were finally included in this study.The meta-analysis revealed that,compared with placebos,calcium supplementation had no effect on the bone mineral densities[the whole-body:SMD with CI=0.43(-0.05-0.91),P=0.08,I2=75%;the 2nd-4th lumbar vertebrae:SMD with 95%CI=0.27(−0.17 to 0.70),P=0.07,I2=0%)].Sensitivity analysis revealed that the results of the whole-body bone mineral density were unstable and that the bone density of the 2nd-4th lumbar spine was robust.Conclusions:The results of this meta-analysis suggested that calcium supplementation did not improve bone mineral density in children.However,there continues to be a need for more high-quality studies to verify this fact in the future.

Berberine protects diabetic nephropathy rats by inhibiting endoplasmic reticulum stress

Objective:The aim of this study was to investigate the effects of Berberine(BBR)on Endoplasmic Reticulum Stress(ERS)in renal tissue of Diabetic Nephropathy(DN).Methods:The DN RAT model was induced by high glucose and high fat diet combined with intraperitoneal injection of Streptozocin.The experiment was divided into 3 groups:normal group(NC group),model group(DN group)and berberine intervention group(DN+BBR group)(n=6).DN+BBR group was treated with 200 mg/kg/d on the basis of the model of DN.NC group and DN group were treated with the same dose of sodium carboxymethyl cellulose.After 6 weeks treatment measured various indicators(include body weight,renal index(KI=kidney weight/body weight),fasting blood glucose(FBG),blood creatinine(SCR),urea nitrogen(BUN)and 24h urine protein(24h Pro)).The pathological changes of kidney were observed by HE,PAS and Masson staining.The changes of glomerulus and renal interstitium were observed by transmission electron microscope.The expression of PERK,IRE1,ATF6,CHOP and Caspase3 were detected by immunohistochemical staining.Results:(1)SCR,Bun,FBG and 24hUpro in DN group were significantly higher than those in NC group and the renal function of DN group severely impaired.Compare with DN group the renal function of DN+BBR group was significant improved.There were significant differences in SCR,Bun,FBG and 24hUpro in each group(p<0.01).(2)The results of HE,PAS and Masson staining showed that the glomerulus in DN group was more irregular and larger than that in NC group;the lumen of glomerulus became narrowed,diffuse mesangial matrix was increased and renal tubule was edematous.The glycogen deposits and collagen fibers in the renal interstitium were increased and inflammatory cells were infiltrated.After the berberine rescued,the glomerular condition of DN+BBR group was obviously improved;the edema of renal tubules was alleviated;the deposition of glycogen was decreased and the collagenous fibers accumulation is relatively reduced.(3)The results of transmission electron microscope showed that the podocytes of DN Group were irregular and a large number of podocytes fused and broken.The basement membrane was inhomogeneous and thickened.Whereas,the morphological function of podocyte of DN+BBR Group was improved.And the basement membrane was slightly thickened.(4)Immunohistochemistry shows that the expression of Chop,PERK,IRE1,ATF6 and Caspase3 in DN group was significantly increased and the DN+BBR group was contrarily.The difference of protein expression was statistically significant(p<0.05).Conclusion:These findings provide insights into the BBR can significantly improve the structure and function of kidney in DN rats.The hypothesis is that BBR can suppress endoplasmic reticulum stress and reduce the apoptosis of kidney cells,thus prevent the progress of DN and protect the kidney tissue.

Morphology and Phase Composition of Gelatin-Starch Blends

Morphology and phase compositions of different starch-gelatin blends were investigated by various microscopes： optical, SEM and synchrotron FTIR microscopy. A high amylose （80%） corn starch, grafted with hydroxypropyl to enhance flexibilty and hydrophilicity, and plasticized by poly（ethylene glycol） （PEG）, was used in this work. SEM revealed that the surface became smoother after adding PEG. Optical microscopy observation revealed that compatibility between gelatin and starch was improved by adding PEG. An FTIR beam focused on a 5 ~tm x 5 ~tm detection area by the micro-spectroscope was used to map chemical composition. The ratio of areas of the saccharide bands （1180-953 cm-1） and the amide I and II bands （1750-1483 cm-1） was used to monitor the relative distributions of the two components in the blends. The FTIR maps indicated that gelatin constituted the continuous phase up to 80% of starch content. All of the FTIR spectra showed contributions from both starch and gelatin absorptions, therefore indicating that complete demixing with pure starch and gelatin domains did not occur. The PEG improved the compatibility of the gelatin-starch blends.

Improving the Mechanical and Tribological Properties of NiTi Alloys by Combining Cryo-Rolling and Post-Annealing

By combining cryo-rolling and post-annealing treatments,the nanostructured NiTi alloy is produced.A diff erential scanning calorimetry measurement was used to test the eff ect of the preparation process on phase transformation.The cryo-rolling changes the tensile fracture of NiTi alloy to a ductile manner.Interestingly,the recovered structure exhibits signifi cant strength improvement,while the tensile plasticity is still comparable to that of the coarse-grained structure.This optimized mechanical performance is due to the strengthening eff ect of refi ned microstructure and the high work hardening capability rendered by moderate dislocation density.Ball-on-plate reciprocating dry-sliding wear test reveals that the nanostructured NiTi alloy also has enhanced wear resistance,which is primarily ascribed to the high content of residue martensite formed during cryo-rolling.These results provide an eff ective route to optimize the mechanical and wear properties of NiTi alloys.

Ultrafine-Grained Microstructure and Improved Mechanical Behaviors of Friction Stir Welded Cu and Cu–30Zn Joints

Ultra-strong joints of pure Cu and Cu–30Zn alloy were obtained by friction stir welding under flowing water. The effects of heat inputting condition and material characteristics on the morphologies, microstructures and mechanical properties of welding joints were studied. Defect-free stirring zones of pure Cu and Cu–30Zn were characterized by onion-ringed structure and plastic flowing bands, respectively. Both low stacking fault energy and fast cooling condition contributed to the formation of small recrystallized grains less than 1 μm in stirring zones. The welding joints in both materials exhibited enhanced mechanical performances due to ultrafine-grained microstructure in stirring zones and disappearance of soft heataffected-zone. The technique of digital image correlation was used to study the tensile deformation behaviors of welding joints and verify the improved tensile properties.

Convergence and Optimality of Adaptive Regularization for Ill-posed Deconvolution Problems in Infinite Spaces

The adaptive regularization method is first proposed by Ryzhikov et al. in [6] for the deconvolution in elimination of multiples which appear frequently in geoscience and remote sensing. They have done experiments to show that this method is very effective. This method is better than the Tikhonov regularization in the sense that it is adaptive, i.e., it automatically eliminates the small eigenvalues of the operator when the operator is near singular. In this paper, we give theoretical analysis about the adaptive regularization. We introduce an a priori strategy and an a posteriori strategy for choosing the regularization parameter, and prove regularities of the adaptive regularization for both strategies. For the former, we show that the order of the convergence rate can approach O（｜｜n｜｜^4v/4v＋1） for some 0 〈 v 〈 1, while for the latter, the order of the convergence rate can be at most O（｜｜n｜｜^2v/2v＋1） for some 0 〈 v 〈 1.