Silicon carbide ceramics with different thicknesses/diameter ratios were prepared by using ultra-fine silicon carbide powder with the sintering additives of 1.0 wt% boron and 1.5 wt% carbon. The influence of thickness...Silicon carbide ceramics with different thicknesses/diameter ratios were prepared by using ultra-fine silicon carbide powder with the sintering additives of 1.0 wt% boron and 1.5 wt% carbon. The influence of thickness/diameter ratio on the microstructure and density of SiC ceramics was investigated in detail. The experimental results show that the addition of boron and carbon sintering aids can promote the densification process of SiC ceramic, leading to the low sintering temperature and improve mechanical properties. At 1950 ℃, SiC ceramic with a density of 99% exhibits Young's modulus, hardness, and flexural strength of 476 MPa, 28.3 GPa, and 334 MPa, respectively. It is found that long holding time has a positive effect on the uniformity of the microstructure and density distribution of SiC ceramics with large thickness/diameter ratios. Additionally, the sintering additive of boron can solid-solve into SiC, and then facilitate the phase transformation of SiC to form 6H-SiC and 4H-SiC composite ceramics.展开更多
A novel approach is proposed for computing the minimum thickness of a metal foil that can be achieved by asymmetric rolling using rolls with identical diameter. This approach is based on simultaneously solving Tseliko...A novel approach is proposed for computing the minimum thickness of a metal foil that can be achieved by asymmetric rolling using rolls with identical diameter. This approach is based on simultaneously solving Tselikov equation for the rolling pressure and the modified Hitchcock equation for the roller flattening. To minimize the effect of the elastic deformation on the equal flow per second during the ultrathin foil rolling process, the law of conservation of mass was employed to compute the proportions of the forward slip, backward slip, and the cross shear zones in the contact arc, and then a formula was derived for computing the minimum thickness for asymmetric rolling. Experiment was conducted to find the foil minimum thickness for 304 steel by asymmetric rolling under the asymmetry ratios of 1.05, 1.15 and 1.30. The experimental results are in good agreement with the calculated ones. It was validated that the proposed formula can be used to calculate the foil minimum thickness under the asymmetric rolling condition.展开更多
AIM: To compare retinal artery-vein diameters(RAVDs)of patients with pseudoexfoliation(PSX) syndrome with healthy controls and investigate the correlations between retinal nerve fiber layer(RNFL) thickness parameters ...AIM: To compare retinal artery-vein diameters(RAVDs)of patients with pseudoexfoliation(PSX) syndrome with healthy controls and investigate the correlations between retinal nerve fiber layer(RNFL) thickness parameters and RAVDs.METHODS: Seventeen eyes with PSX and 17 eyes of age-matched controls were included in the study. All participants underwent routine ophthalmological examination, Humphrey visual field and RNFL examination by using Stratus OCT. Retinal images were obtained by using a retinal camera(Topcon 501X).RAVDs were measured from inferior nasal, inferior temporal, superior nasal and superior temporal arcuates by using IMAGEnet software. Superior, inferior, nasal,temporal and average RNFL thicknesses were recorded.RAVDs and RNFL parameters in groups and correlations were analyzed by Mann-Whitney U and Spearmann correlation tests.RESULTS: Only inferior quadrant and average RNFL thickness were detected thinner in the PSX group compared with control group(P =0.009, P =0.038,respectively). No statistically significant difference regarding RAVDs was found between two groups.CONCLUSION: RAVDs seems to be comparable in the PSX and control group. RNFL is thinner in the inferior quadrant in the PSX group. RNFL thickness and RAVDs show significant correlations in both groups. This correlation doesn’t seem to be specific to PSX.展开更多
Renal transplant （RT） recipients have a high risk of developing cardiovascular diseases. However, the effects of renal transplantation on the development of arteriosclerosis have been controversial. The carotid inti...Renal transplant （RT） recipients have a high risk of developing cardiovascular diseases. However, the effects of renal transplantation on the development of arteriosclerosis have been controversial. The carotid intima-media thickness （CIMT） and diameter （CD） are important indicators of vascular remodeling and arteriosclerosis. In this study, 31 patients with hemodialysis （HD）, 31 RT recipients and 84 age- and gender-matched control subjects were enrolled. Their CIMT and CD were measured by ultrasonic radiofrequency tracking, and the linear regression models and Z test were used to identify the progression of arteriosclerosis and the risk factors. Compared with HD group, RT group had significantly lower CIMT and CD. CIMT was found to be associated with age, body weight, resistance index and diastolic velocity, while CD was associated significantly with age, body weight, pulsatility index, end diastolic velocity and diastolic blood pressure （DBP）, respectively. The correlation curves between CIMT and age showed the slopes of curves were decreased successively in control, RT and HD groups, and the curves between CD and age showed the slopes were decreased in order of RT 〉 control 〉 HD groups. It was concluded that CIMT and CD were significantly correlated with age in RT and moderately with age in HD patients. RT could reduce the progress of arteriosclerosis in patients with end-stage renal disease.展开更多
Hot-rolled wide strip for production of large diameter,heavy gauged(up to 19 mm) helical line pipe grade X80 was a priority development over the last three years.Microstructure,texture and mechanical properties of str...Hot-rolled wide strip for production of large diameter,heavy gauged(up to 19 mm) helical line pipe grade X80 was a priority development over the last three years.Microstructure,texture and mechanical properties of strips have been characterised.Also the welding conditions have been simulated.The favourable microstructure is achieved by the proper selection of an appropriate chemical composition of low carbon content and increased niobium micro alloying in combination with suitable strictly controlled hot-rolling parameters.The addition of niobium in combination with the adjustment of other alloying elements increases the recrystallisation stop temperature and thus makes it possible to apply a high temperature processing(HTP) concept.The homogeneous bainitic microstructure across the strip gauge is then formed during accelerated cooling on the run-out table of the hot-rolling mill.All results indicated excellent properties of these hot strips which make it suitable for spiral pipes of grade X80 for example 18.9mm×Φ1 220 mm at dimension.展开更多
Background: Accurate determination of gestational age has become important for deciding the appropriate time for termination of the pregnancy as well as to monitor the fetal growth during the entire period of pregnanc...Background: Accurate determination of gestational age has become important for deciding the appropriate time for termination of the pregnancy as well as to monitor the fetal growth during the entire period of pregnancy. Objective: The aim of the study was to assess whether the trans-cerebellar diameter, placental thickness or combining both of them is more accurate for assessment of gestational age in the 3<sup>rd</sup> trimester of pregnancy. Patients and Methods: This is a cross sectional study conducted at outpatient Clinic and Obstetric ward, Ain Shams University Maternity Hospital, over a period of six months from March 2019 to September 2019. One hundred pregnant women were recruited according to inclusion criteria either from outpatient clinic or were admitted in obstetric ward Ain Shams Maternity Hospital to find out the most accurate fetal biometric measurement in the third trimester either trans-cerebellar diameter placental thickness or both compared to reliable LMP (last menstrual period) dates confirmed by crown rump length (CRL) in the first trimester. Results: Trans-cerebellar diameter mean ± SD was 46.0 ± 3.5 with range 38.2 - 51.7. The mean of placental thickness was 39.6 ± 7.1 with range 22.8 - 54.3. Placental thickness had highest determination (0.813) for last menstrual period followed by trans-cerebellar diameter (0.802). Combining trans-cerebellar diameter and placental thickness increased determination (0.902) for last menstrual period. Conclusion: Combined use of trans-cerebellar diameter and placental thickness in the third trimester of pregnancy is a reliable indicator for gestational age in women whose last menstrual period is unreliable or unknown, but placental thickness had higher accuracy than trans-cerebellar diameter.展开更多
AIMTo determine the effect of suction duration on thickness and diameter of corneal flap created by microkeratome in porcine eyes in laser in situ keratomileusis (LASIK).
This study compared proximal femoral morphology in patients living in soft and hard water regions. The proximal femoral morphology of two groups of 70 patients living in hard and soft water regions with a mean age of ...This study compared proximal femoral morphology in patients living in soft and hard water regions. The proximal femoral morphology of two groups of 70 patients living in hard and soft water regions with a mean age of 72.29 (range: 50 to 87 years) was measured using an antero-posterior radiograph of the non-operated hip with magnification adjusted. The medullary canal diameter at the level of the lesser trochanter (LT) was significantly wider in patients living in the hard water region (mean width: 1.9 mm wider;p = 0.003). No statistical significant difference was found in the medullary canal width at 10 cm below the level of LT, Dorr index, or Canal Bone Ratio (CBR). In conclusion, the proximal femoral morphology does differ in patients living in soft and hard water areas. These results may have an important clinical bearing in patients undergoing total hip replacement surgery. Further research is needed to determine whether implant survivorship is affected in patients living in hard and soft water regions.展开更多
Lead-free hybrid double perovskites(LFHDPs) have received a lot of attention due to their environmental friendliness and promising attributes. However, studying the effect of film thickness on LFHDPs optoelectronic pr...Lead-free hybrid double perovskites(LFHDPs) have received a lot of attention due to their environmental friendliness and promising attributes. However, studying the effect of film thickness on LFHDPs optoelectronic properties has not yet been investigated. Herein, we synthesized two new Ruddlesden–Popper LFHDPs, namely(C_(5)H_(12)N)_(4)AgBiI_(8)(CAB-1) and(C_(6)H_(14)N)_(4)Ag Bi I8(CAB-2) using cyclopentylamine and cyclohexylamine as monoamine ligands. Indeed, these two Ag(Ⅰ)-Bi(Ⅲ) LFHDPs form smooth and uniform films ranging in thickness from 250 nm to 1 μm, with preferred orientations. Notably, the studies on the optical properties showed that the direct band gap value decreased from 2.17 e V to 1.91 e V for CAB-1 and from 2.05 e V to 1.86 e V for CAB-2 with increasing thickness. Accordingly, photo-current response using a xenon lamp revealed a significant difference of over 1000 n A between light and dark conditions for1 μm-thickness films, suggesting potential for light harvesting. Other than that, thicker films of CAB-1and CAB-2 exhibit high stability for 90 days in a relatively humid environment(RH of 55%), paving the way for promising optoelectronic applications.展开更多
Background:It is found to have association of facial parameters with trisomy 21 fetuses(T 21).We have compared prenasal thickness(PNT),nasal bone length(NBL),and the PNT:NBL ratio of normal fetuses with fetuses with t...Background:It is found to have association of facial parameters with trisomy 21 fetuses(T 21).We have compared prenasal thickness(PNT),nasal bone length(NBL),and the PNT:NBL ratio of normal fetuses with fetuses with trisomy 21(T 21)between 16 and 25 weeks of gestation as a diagnostic tool for T 21.Methods:Facial profile images in the two dimensional(2D)gray scale were assessed to measure fetal NBL and PNT between 16 and 25 weeks of gestation.The PNT:NBL ratio of the fetuses was calculated.Nomograms were constructed from the data of morphologically normal fetuses at live birth.The PNT,NBL,and PNT:NBL ratio of fetuses with confirmed T 21(n=31)and morphologically normal fetuses at live birth(controls,n=3485)were compared.Results:Nomograms for PNT,NBL,and the PNT:NBL ratio were constructed.In T 21 fetuses,PNT(>95th percentile),NBL(<5th percentile),and the PNT:NBL ratio(>95th percentile)showed a sensitivity of 25%,29%,and 45%for PNT,NBL,and PNT:NBL,respectively,and specificity of 95%,96%,and 94%,for PNT,NBL,and PNT:NBL,respectively.All of these markers showed a negative predictive value of 99%.Conclusion:PNT,NBL,and the PNT:NBL ratio have high diagnostic value for fetuses with Down syndrome and can be incorporated easily in the current second trimester screening protocol for T 21.PNT,NBL,and the PNT:NBL ratio are more specific markers for Down syndrome than those used in previous studies.展开更多
Mg alloy matrix composites reinforced with short carbon fibers(C_(sf)/Mg)are considered as potential candidates for integrated structural-functional electronic parts that satisfy the requirements of lightweight,excell...Mg alloy matrix composites reinforced with short carbon fibers(C_(sf)/Mg)are considered as potential candidates for integrated structural-functional electronic parts that satisfy the requirements of lightweight,excellent mechanical properties,and heat dissipation.However,the different characteristics of C_(sf)and Mg alloy make the interface a critical issue affecting the synergistic improvement of thermal and mechanical properties of the composites.Here,Cu coating with different thicknesses is introduced to modify the C_(sf)/Mg interface,so as to simultaneously enhance the thermal and mechanical performances,which can combine the advantages of coating modification and matrix alloying.Results reveal that thermal diffusivity(TD)of 3-C_(sf)-Cu/Mg composites is as high as 22.12 mm^(2)/s and an enhancement of 52.97%is achieved compared with C_(sf)/Mg composites,as well as 16.3%enhancement of ultimate compressive strength(UCS)in the longitudinal direction,8.84%improvement of UCS in the transverse direction,and 53.08%increasement of ultimate tensile strength(UTS).Such improvement can be ascribed to the formation of intermetallic compounds.The formation of intermetallic compounds can not only effectively alleviate the lattice distortion of the matrix and decrease interfacial thermal resistance,but also bear the loads.Our work is of great significance for designing C_(sf)/Mg composites with integrated structure and function.展开更多
Due to the influence of karst cave development and route selection,the location relationship between concealed karst cave and tunnel is more random.In order to explore the influence rule of karst cave location on the ...Due to the influence of karst cave development and route selection,the location relationship between concealed karst cave and tunnel is more random.In order to explore the influence rule of karst cave location on the minimum safe thickness of water-proof rock mass,a simplified calculation model of water-proof rock mass thickness when the karst cave is located at any location around the tunnel is established,and the influence of multiple factors on the overall stability of water-proof rock mass is considered.Based on the cusp catastrophe theory,the analytical expressions for the safety thickness of waterproof rock mass are derived.Based on the finite difference principle,the analytical expressions of the safety thickness of water-proof rock mass are verified.In order to improve the application range of the analytical formula derived in this paper,the analytical formula is optimized based on the instability principle differences between the simplified calculation model and the elastic compressive bar.The research results show that the necessary condition solution is more applicable and much safer than the sufficient condition solution.Tectonic stress,rock beam length and karst cave water pressure are significantly positively correlated with the safe thickness of the waterproof rock mass.The calculated results of the semioptimized formula and the unoptimized formula are constant values,independent of the karst cave location.While the calculated results of the fully optimized formula are variable values,correlated with the karst cave location,the thickness of the waterproof rock mass gradually decreases as the karst cave location moves from the top of the tunnel to the bottom of the tunnel.The unoptimized formula does not consider the influence of the lateral force of the rock beam,and is not suitable for the working condition with large lateral force,the calculation results of the semi-optimized formula and the fully optimized formula are not very different and are biased to safety,so it can be given priority.展开更多
The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusio...The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusion height and random position distribution of abrasive grains on the abrasive wheel surface.This study investigated the distribution of undeformed chip thickness and grinding force considering the non-uniform characteristics of abrasive wheel in the grinding of K4002 nickel-based superalloy.First,a novel grinding force model was established through a kinematic-geometric analysis and a grain-workpiece contact analysis.Then,a series of grinding experiments were conducted for verifying the model.The results indicate that the distribution of undeformed chip thickness is highly consistent with the Gaussian distribution formula.The increase in the grinding depth mainly leads to an increase in the average value of Gaussian distribution.On the contrary,the increase in the workpiece infeed speed or the decrease in the grinding speed mainly increases the standard deviation of Gaussian distribution.The average and maximum errors of the grinding force model are 4.9%and 14.6%respectively,indicating that the model is of high predication accuracy.展开更多
While the fire protection function of tree bark has been extensively documented,other critical functions,including storage and mechanical support,have received less attention.In this study we examined:(1)the allometry...While the fire protection function of tree bark has been extensively documented,other critical functions,including storage and mechanical support,have received less attention.In this study we examined:(1)the allometry of bark thickness(and biomass)against wood radius(and biomass)at a disc level,(2)differences in bark allocation between the ratio and the regression approaches,(3)differences between bark thickness and biomass as metrics of bark allocation,and(4)how bark allocation is associated with the evolution of wood from non-porous to diffuse-porous and ring-porous types.Thickness and biomass of bark and wood were measured using trunk discs of 88 individual trees of 36 species in a temperate forest characterized by a long fire interval.Allometric relationships of bark thickness(and biomass)against wood radius(and biomass)explained why both relative bark thickness and biomass decreased with increasing stem diameter.Variations in both among species varied by factors of 3.5 to 7.5 depending on the measurement methods.The ratio approach produced higher estimates of both relative bark thickness and biomass compared to the regression approach,while relative bark thickness was significantly lower than relative bark biomass.Ring-porous species exhibited higher bark thickness based on the ratio approach,which might reflect evolutionary adaptations where ring-porous species have developed thicker bark as protection:thermal insulation against freeze-thaw embolism coupled with carbohydrate reservoirs for hydraulic repair.The regression slope of bark allocation against wood density increased along the wood porosity gradient,demonstrating evolutionary biomechanical coordination between bark and wood.These findings highlight systematic coupling between bark and xylem multifunctionality.展开更多
To advance the understanding of the corrosion behavior of stainless steel bellows in marine atmospheric environments and enhance the precision of service life predictions,this study employs finite element simulations ...To advance the understanding of the corrosion behavior of stainless steel bellows in marine atmospheric environments and enhance the precision of service life predictions,this study employs finite element simulations to investigate the pitting corrosion rates and pit morphologies of bellows peaks and troughs under varying electrolyte film thicknesses.The model incorporates localized electrochemical reactions,oxygen concentration,and homogeneous solution reactions.For improved computational accuracy,the fitted polarization curve data were directly applied as nonlinear boundary conditions on the electrode surface via interpolation functions.Simulation results reveal that the peak regions exhibit faster corrosion rates than the trough regions.With increasing electrolyte film thickness(from 10μm to 500μm),corrosion rates at both peaks and troughs decrease progressively,and after 120 hours of simulation,the maximum corrosion rate at the peaks declines from 0.720 mm/a to 0.130 mm/a,and at the troughs from 0.520 mm/a to 0.120 mm/a,with the disparity in corrosion rates diminishing over time.Furthermore,as corrosion progresses,pits propagate deeper into the substrate,exhibiting both vertical penetration and lateral expansion along the passive film interface,ultimately breaching the substrate.This research offers valuable insights into designing corrosion mitigation strategies for stainless steel bellows in marine environments.展开更多
The performance and price of copper-based micro linear products are determined by the diameter uniformity.How to accurately detect the wire diameter of long-length copper based micro linear products without cutting or...The performance and price of copper-based micro linear products are determined by the diameter uniformity.How to accurately detect the wire diameter of long-length copper based micro linear products without cutting or damage has always been a technical concern for production enterprises.Herein,a novel approach was developed for nondestructive detection of the average diameter at any given segment of a long copper wire by assessing the adsorption capacity of arginine on its surface.The amount of adsorbent on the surface of the copper wire exhibits a positive correlation with the area,which can be detected by extractive electrospray ionization mass spectrometry(EESI-MS)after online elution with ammonia.The experimental results demonstrated that the analysis can be completed within 15 min,with a good linear relationship between copper wires with different diameters and the adsorption capacity of arginine.The linear correlation coefficient R2was 0.995,the relative standard deviation was 1.10%-2.81%,and the detection limit reached 2.5μm(length of segment=4 cm),showing potential applications for facile measurement of the average diameter of various metal wires.展开更多
BACKGROUND Despite growing evidence on endoscopic full thickness resection(EFTR),data on segment-specific outcomes in real-world patients remain limited.AIM To investigate segment-specific outcomes of EFTR using a ful...BACKGROUND Despite growing evidence on endoscopic full thickness resection(EFTR),data on segment-specific outcomes in real-world patients remain limited.AIM To investigate segment-specific outcomes of EFTR using a full-thickness resection device(FTRD)for neoplastic colorectal lesions.METHODS In this multicenter,retrospective study,EFTR was conducted in unselected realworld patients referred to participating German centers after colonoscopy confirmed EFTR eligibility.The primary outcome was histologically complete resection(R0)of the lesion,including segment-specific outcomes and adverse events(AE).Additional efficacy and safety parameters were investigated by colonic topography for up to 30 days.RESULTS The analysis included 102 patients(64 males,38 females)with a median age of 70 years.EFTR via FTRD was technically successful in all patients.The R0 rate was 81.4%,segment-specifically ranging from 85.0%(rectum),84.6%(descending colon),84.0%(ascending colon),83.3%(cecum),and 76.5%(sigmoid colon)to 73.3%(transverse colon).Examination time was longer in proximal parts compared to the rectosigmoid(non-significant).Overall,33 patients(32.4%)experienced AE,including only one major complication(0.98%;perforation of sigmoid colon).Abdominal postsurgical pain(18.6%),hematochezia(9.8%),and hemoglobin decline(7.8%)were the most frequent minor complications.Transverse colon lesions had the numerically highest rate of AE,with 8 of 15 patients(53.3%)affected.CONCLUSION EFTR is efficacious for neoplastic colorectal lesions,though R0 rates vary by location.This may impact patient education,selection of the operator,and consideration of laparoscopy surgery.展开更多
Background Postoperative delirium is one of the most common complications in the older surgical population,but its pathogenesis and biomarkers are largely undetermined.Retinal layer thickness has been demonstrated to ...Background Postoperative delirium is one of the most common complications in the older surgical population,but its pathogenesis and biomarkers are largely undetermined.Retinal layer thickness has been demonstrated to be associated with cognitive function in mild cognitive impairment and patients with Alzheimer’s disease.However,relatively little is known about possible retinal layer thickness among patients with postoperative delirium.Aims We aimed to investigate the relationship between retinal layer thickness and postoperative delirium in this cross-sectional study.Methods The participants(≥65 years old)having elective surgery under general anaesthesia were screened via medical records from Shanghai 10th People’s Hospital.Preoperative macular thickness and peripapillary retinal nerve fibre layer(RNFL)thickness were measured using optical coherence tomography(OCT).The Confusion Assessment Method(CAM)algorithm and CAM-Severity(CAM-S)were used to assess the incidence and severity of postoperative delirium on the first,second and third days after surgery.Results Among 169 participants(mean(standard deviation(SD)71.15(4.36)years),40(24%)developed postoperative delirium.Notably,individuals who developed postoperative delirium exhibited thicker preoperative macular thickness in the right eye compared with those who did not(mean(SD)283.35(27.97)µm vs 273.84(20.14)µm,p=0.013).Furthermore,the thicker preoperative macular thickness of the right eye was associated with a higher incidence of postoperative delirium(adjusted odds ratio 1.593,95%confidence interval(CI)1.093 to 2.322,p=0.015)and greater severity(adjusted mean difference(β)=0.256,95%CI 0.037 to 0.476,p=0.022)after adjustment for age,sex and Mini-Mental State Examination(MMSE)scores.However,such a difference or association did not appear in the left macular or bilateral peripapillary RNFL thicknesses.Conclusions Current findings demonstrated that preoperative macular thickness might serve as a potential non-invasive marker for the vulnerability of developing postoperative delirium in older surgical patients.Further large-scale validation studies should be performed to confirm these results.展开更多
Background Backfat thickness(BFT)is a vital economic trait in pigs,reflecting subcutaneous fat levels that affect meat quality and production efficiency.As a complex trait shaped by multiple genetic factors,BFT has be...Background Backfat thickness(BFT)is a vital economic trait in pigs,reflecting subcutaneous fat levels that affect meat quality and production efficiency.As a complex trait shaped by multiple genetic factors,BFT has been studied using genome-wide association studies(GWAS)and linkage analyses to locate fat-related quantitative trait loci(QTLs),but pinpointing causal variants and genes is hindered by linkage disequilibrium and limited regulatory data.This study aimed to dissect the QTLs affecting BFT on Sus scrofa chromosome 1(SSC1),elucidating regulatory variants,effector genes,and the cell types involved.Results Using whole-genome genotyping data from 3,578 pigs and phenotypic data for five BFT traits,we identified a 630.6 kb QTL on SSC1 significantly associated with these traits via GWAS and fine-mapping,pinpointing 34 candidate causal variants.Using deep convolutional neural networks to predict regulatory activity from sequence data integrated with detailed pig epigenetic profiles,we identified five SNPs potentially affecting enhancer activity in specific tissues.Notably,rs342950505(SSC1:161,123,588)influences weak enhancer activity across multiple tissues,including the brain.High-throughput chromosome conformation capture(Hi-C)analysis identified that rs342950505 interacts with eight genes.Chromatin state annotations confirmed enhancer activity at this QTL in the cerebellum.Leveraging these insights,single-cell ATAC-seq revealed a chromatin accessibility peak encompassing rs342950505 that regulates PMAIP1 expression in inhibitory neurons via enhancer-mediated mechanisms,with an adjacent peak modulating CCBE1 expression in neuroblasts and granule cells.Transcriptome-wide association studies(TWAS)confirmed PMAIP1's role in the hypothalamus,and Mendelian randomization(MR)validated PMAIP1 and CCBE1 as key brain expression quantitative trait locus(eQTL)effectors.We propose that the variant rs342950505,located within a regulatory peak,modulates PMAIP1 expression in inhibitory neurons,potentially influencing energy homeostasis via hypothalamic regulation.Similarly,CCBE1 may contribute to this process.Conclusions Our results,through systematic dissection of pleiotropic BFT-associated loci,provide a framework to elucidate regulatory mechanisms of complex traits,offering insights into polygenic control through lipid metabolism and neural signaling pathways.展开更多
The Qinghai-Tibet Plateau possesses the thickest continental crust on Earth,yet the timing of its formation remains debated.In this study,we conducted zircon U-Pb isotopic dating,geochemical and Sr-Nd-Pb-Hf isotopic a...The Qinghai-Tibet Plateau possesses the thickest continental crust on Earth,yet the timing of its formation remains debated.In this study,we conducted zircon U-Pb isotopic dating,geochemical and Sr-Nd-Pb-Hf isotopic analyses on the Xuexiumaer biotite quartz monzonite porphyry(BQMP)sampled from the Lake Dajia area in southern Gangdese.This study aims to estimate the paleo-crustal thickness beneath this region during the early India-Asia collision stage using whole-rock Sr/Y and(La/Yb)N ratios as proxies.Results reveal that the Xuexiumaer BQMP was formed at~51 Ma in a collisional tectonic setting following Neo-Tethyan slab breakoff,and is an I-type granitoid derived primarily from partial melting of juvenile mafic lower crust with subordinate ancient crustal input.The estimated paleo-crustal thickness in the Lake Dajia area at~51 Ma is less than 40 km.This indicates that although the Qinghai-Tibet Plateau had already undergone significant crustal thickening and attained an exceptionally thick crust(>50 km)prior to the India-Asia collision as demonstrated by previous studies,some regions still maintained a crust only slightly thicker than the average continental crust(~35 km)at the initial collision stage.This limited crustal thickening likely resulted from underplating of subduction-related mafic magma at the mantle-crust boundary.展开更多
基金Funded by the National Key Research and Development Plan of China (No.2017YFB0310400)the National Natural Science Foundation of China (No.5167020705)
文摘Silicon carbide ceramics with different thicknesses/diameter ratios were prepared by using ultra-fine silicon carbide powder with the sintering additives of 1.0 wt% boron and 1.5 wt% carbon. The influence of thickness/diameter ratio on the microstructure and density of SiC ceramics was investigated in detail. The experimental results show that the addition of boron and carbon sintering aids can promote the densification process of SiC ceramic, leading to the low sintering temperature and improve mechanical properties. At 1950 ℃, SiC ceramic with a density of 99% exhibits Young's modulus, hardness, and flexural strength of 476 MPa, 28.3 GPa, and 334 MPa, respectively. It is found that long holding time has a positive effect on the uniformity of the microstructure and density distribution of SiC ceramics with large thickness/diameter ratios. Additionally, the sintering additive of boron can solid-solve into SiC, and then facilitate the phase transformation of SiC to form 6H-SiC and 4H-SiC composite ceramics.
基金Projects(51374069U1460107)supported by the National Natural Science Foundation of China
文摘A novel approach is proposed for computing the minimum thickness of a metal foil that can be achieved by asymmetric rolling using rolls with identical diameter. This approach is based on simultaneously solving Tselikov equation for the rolling pressure and the modified Hitchcock equation for the roller flattening. To minimize the effect of the elastic deformation on the equal flow per second during the ultrathin foil rolling process, the law of conservation of mass was employed to compute the proportions of the forward slip, backward slip, and the cross shear zones in the contact arc, and then a formula was derived for computing the minimum thickness for asymmetric rolling. Experiment was conducted to find the foil minimum thickness for 304 steel by asymmetric rolling under the asymmetry ratios of 1.05, 1.15 and 1.30. The experimental results are in good agreement with the calculated ones. It was validated that the proposed formula can be used to calculate the foil minimum thickness under the asymmetric rolling condition.
文摘AIM: To compare retinal artery-vein diameters(RAVDs)of patients with pseudoexfoliation(PSX) syndrome with healthy controls and investigate the correlations between retinal nerve fiber layer(RNFL) thickness parameters and RAVDs.METHODS: Seventeen eyes with PSX and 17 eyes of age-matched controls were included in the study. All participants underwent routine ophthalmological examination, Humphrey visual field and RNFL examination by using Stratus OCT. Retinal images were obtained by using a retinal camera(Topcon 501X).RAVDs were measured from inferior nasal, inferior temporal, superior nasal and superior temporal arcuates by using IMAGEnet software. Superior, inferior, nasal,temporal and average RNFL thicknesses were recorded.RAVDs and RNFL parameters in groups and correlations were analyzed by Mann-Whitney U and Spearmann correlation tests.RESULTS: Only inferior quadrant and average RNFL thickness were detected thinner in the PSX group compared with control group(P =0.009, P =0.038,respectively). No statistically significant difference regarding RAVDs was found between two groups.CONCLUSION: RAVDs seems to be comparable in the PSX and control group. RNFL is thinner in the inferior quadrant in the PSX group. RNFL thickness and RAVDs show significant correlations in both groups. This correlation doesn’t seem to be specific to PSX.
文摘Renal transplant （RT） recipients have a high risk of developing cardiovascular diseases. However, the effects of renal transplantation on the development of arteriosclerosis have been controversial. The carotid intima-media thickness （CIMT） and diameter （CD） are important indicators of vascular remodeling and arteriosclerosis. In this study, 31 patients with hemodialysis （HD）, 31 RT recipients and 84 age- and gender-matched control subjects were enrolled. Their CIMT and CD were measured by ultrasonic radiofrequency tracking, and the linear regression models and Z test were used to identify the progression of arteriosclerosis and the risk factors. Compared with HD group, RT group had significantly lower CIMT and CD. CIMT was found to be associated with age, body weight, resistance index and diastolic velocity, while CD was associated significantly with age, body weight, pulsatility index, end diastolic velocity and diastolic blood pressure （DBP）, respectively. The correlation curves between CIMT and age showed the slopes of curves were decreased successively in control, RT and HD groups, and the curves between CD and age showed the slopes were decreased in order of RT 〉 control 〉 HD groups. It was concluded that CIMT and CD were significantly correlated with age in RT and moderately with age in HD patients. RT could reduce the progress of arteriosclerosis in patients with end-stage renal disease.
文摘Hot-rolled wide strip for production of large diameter,heavy gauged(up to 19 mm) helical line pipe grade X80 was a priority development over the last three years.Microstructure,texture and mechanical properties of strips have been characterised.Also the welding conditions have been simulated.The favourable microstructure is achieved by the proper selection of an appropriate chemical composition of low carbon content and increased niobium micro alloying in combination with suitable strictly controlled hot-rolling parameters.The addition of niobium in combination with the adjustment of other alloying elements increases the recrystallisation stop temperature and thus makes it possible to apply a high temperature processing(HTP) concept.The homogeneous bainitic microstructure across the strip gauge is then formed during accelerated cooling on the run-out table of the hot-rolling mill.All results indicated excellent properties of these hot strips which make it suitable for spiral pipes of grade X80 for example 18.9mm×Φ1 220 mm at dimension.
文摘Background: Accurate determination of gestational age has become important for deciding the appropriate time for termination of the pregnancy as well as to monitor the fetal growth during the entire period of pregnancy. Objective: The aim of the study was to assess whether the trans-cerebellar diameter, placental thickness or combining both of them is more accurate for assessment of gestational age in the 3<sup>rd</sup> trimester of pregnancy. Patients and Methods: This is a cross sectional study conducted at outpatient Clinic and Obstetric ward, Ain Shams University Maternity Hospital, over a period of six months from March 2019 to September 2019. One hundred pregnant women were recruited according to inclusion criteria either from outpatient clinic or were admitted in obstetric ward Ain Shams Maternity Hospital to find out the most accurate fetal biometric measurement in the third trimester either trans-cerebellar diameter placental thickness or both compared to reliable LMP (last menstrual period) dates confirmed by crown rump length (CRL) in the first trimester. Results: Trans-cerebellar diameter mean ± SD was 46.0 ± 3.5 with range 38.2 - 51.7. The mean of placental thickness was 39.6 ± 7.1 with range 22.8 - 54.3. Placental thickness had highest determination (0.813) for last menstrual period followed by trans-cerebellar diameter (0.802). Combining trans-cerebellar diameter and placental thickness increased determination (0.902) for last menstrual period. Conclusion: Combined use of trans-cerebellar diameter and placental thickness in the third trimester of pregnancy is a reliable indicator for gestational age in women whose last menstrual period is unreliable or unknown, but placental thickness had higher accuracy than trans-cerebellar diameter.
基金Natural Science Foundation of Liaoning Province,China(No.20042081)
文摘AIMTo determine the effect of suction duration on thickness and diameter of corneal flap created by microkeratome in porcine eyes in laser in situ keratomileusis (LASIK).
文摘This study compared proximal femoral morphology in patients living in soft and hard water regions. The proximal femoral morphology of two groups of 70 patients living in hard and soft water regions with a mean age of 72.29 (range: 50 to 87 years) was measured using an antero-posterior radiograph of the non-operated hip with magnification adjusted. The medullary canal diameter at the level of the lesser trochanter (LT) was significantly wider in patients living in the hard water region (mean width: 1.9 mm wider;p = 0.003). No statistical significant difference was found in the medullary canal width at 10 cm below the level of LT, Dorr index, or Canal Bone Ratio (CBR). In conclusion, the proximal femoral morphology does differ in patients living in soft and hard water areas. These results may have an important clinical bearing in patients undergoing total hip replacement surgery. Further research is needed to determine whether implant survivorship is affected in patients living in hard and soft water regions.
基金supported by the National Natural Science Foundation of China (Nos. 22375157 and W2433042)the Key Scientific and Technological Innovation Team of Shaanxi Province(No. 2020TD-001)+1 种基金the Fundamental Research Funds for Central Universities, State Key Laboratory of Electrical Insulation and Power Equipment (No. EIPE23409)the Instrument Analysis Center of Xi’an Jiaotong University for assistance。
文摘Lead-free hybrid double perovskites(LFHDPs) have received a lot of attention due to their environmental friendliness and promising attributes. However, studying the effect of film thickness on LFHDPs optoelectronic properties has not yet been investigated. Herein, we synthesized two new Ruddlesden–Popper LFHDPs, namely(C_(5)H_(12)N)_(4)AgBiI_(8)(CAB-1) and(C_(6)H_(14)N)_(4)Ag Bi I8(CAB-2) using cyclopentylamine and cyclohexylamine as monoamine ligands. Indeed, these two Ag(Ⅰ)-Bi(Ⅲ) LFHDPs form smooth and uniform films ranging in thickness from 250 nm to 1 μm, with preferred orientations. Notably, the studies on the optical properties showed that the direct band gap value decreased from 2.17 e V to 1.91 e V for CAB-1 and from 2.05 e V to 1.86 e V for CAB-2 with increasing thickness. Accordingly, photo-current response using a xenon lamp revealed a significant difference of over 1000 n A between light and dark conditions for1 μm-thickness films, suggesting potential for light harvesting. Other than that, thicker films of CAB-1and CAB-2 exhibit high stability for 90 days in a relatively humid environment(RH of 55%), paving the way for promising optoelectronic applications.
文摘Background:It is found to have association of facial parameters with trisomy 21 fetuses(T 21).We have compared prenasal thickness(PNT),nasal bone length(NBL),and the PNT:NBL ratio of normal fetuses with fetuses with trisomy 21(T 21)between 16 and 25 weeks of gestation as a diagnostic tool for T 21.Methods:Facial profile images in the two dimensional(2D)gray scale were assessed to measure fetal NBL and PNT between 16 and 25 weeks of gestation.The PNT:NBL ratio of the fetuses was calculated.Nomograms were constructed from the data of morphologically normal fetuses at live birth.The PNT,NBL,and PNT:NBL ratio of fetuses with confirmed T 21(n=31)and morphologically normal fetuses at live birth(controls,n=3485)were compared.Results:Nomograms for PNT,NBL,and the PNT:NBL ratio were constructed.In T 21 fetuses,PNT(>95th percentile),NBL(<5th percentile),and the PNT:NBL ratio(>95th percentile)showed a sensitivity of 25%,29%,and 45%for PNT,NBL,and PNT:NBL,respectively,and specificity of 95%,96%,and 94%,for PNT,NBL,and PNT:NBL,respectively.All of these markers showed a negative predictive value of 99%.Conclusion:PNT,NBL,and the PNT:NBL ratio have high diagnostic value for fetuses with Down syndrome and can be incorporated easily in the current second trimester screening protocol for T 21.PNT,NBL,and the PNT:NBL ratio are more specific markers for Down syndrome than those used in previous studies.
基金supported by the National Natural Science Foundation of China(grant no.52231004 and 52072305).
文摘Mg alloy matrix composites reinforced with short carbon fibers(C_(sf)/Mg)are considered as potential candidates for integrated structural-functional electronic parts that satisfy the requirements of lightweight,excellent mechanical properties,and heat dissipation.However,the different characteristics of C_(sf)and Mg alloy make the interface a critical issue affecting the synergistic improvement of thermal and mechanical properties of the composites.Here,Cu coating with different thicknesses is introduced to modify the C_(sf)/Mg interface,so as to simultaneously enhance the thermal and mechanical performances,which can combine the advantages of coating modification and matrix alloying.Results reveal that thermal diffusivity(TD)of 3-C_(sf)-Cu/Mg composites is as high as 22.12 mm^(2)/s and an enhancement of 52.97%is achieved compared with C_(sf)/Mg composites,as well as 16.3%enhancement of ultimate compressive strength(UCS)in the longitudinal direction,8.84%improvement of UCS in the transverse direction,and 53.08%increasement of ultimate tensile strength(UTS).Such improvement can be ascribed to the formation of intermetallic compounds.The formation of intermetallic compounds can not only effectively alleviate the lattice distortion of the matrix and decrease interfacial thermal resistance,but also bear the loads.Our work is of great significance for designing C_(sf)/Mg composites with integrated structure and function.
基金jointly funded by the guangxi Science and Technology Base and Talent Project(AD23026104)the Key Research and Development Program Project in Guangxi(AB23026121)。
文摘Due to the influence of karst cave development and route selection,the location relationship between concealed karst cave and tunnel is more random.In order to explore the influence rule of karst cave location on the minimum safe thickness of water-proof rock mass,a simplified calculation model of water-proof rock mass thickness when the karst cave is located at any location around the tunnel is established,and the influence of multiple factors on the overall stability of water-proof rock mass is considered.Based on the cusp catastrophe theory,the analytical expressions for the safety thickness of waterproof rock mass are derived.Based on the finite difference principle,the analytical expressions of the safety thickness of water-proof rock mass are verified.In order to improve the application range of the analytical formula derived in this paper,the analytical formula is optimized based on the instability principle differences between the simplified calculation model and the elastic compressive bar.The research results show that the necessary condition solution is more applicable and much safer than the sufficient condition solution.Tectonic stress,rock beam length and karst cave water pressure are significantly positively correlated with the safe thickness of the waterproof rock mass.The calculated results of the semioptimized formula and the unoptimized formula are constant values,independent of the karst cave location.While the calculated results of the fully optimized formula are variable values,correlated with the karst cave location,the thickness of the waterproof rock mass gradually decreases as the karst cave location moves from the top of the tunnel to the bottom of the tunnel.The unoptimized formula does not consider the influence of the lateral force of the rock beam,and is not suitable for the working condition with large lateral force,the calculation results of the semi-optimized formula and the fully optimized formula are not very different and are biased to safety,so it can be given priority.
基金financially supported by the National Natural Science Foundation of China(Nos.92160301,92060203,52175415 and 52205475)the Science Center for Gas Turbine Project(Nos.P2022-AB-Ⅳ-002-001 and P2023-B-Ⅳ-003-001)+3 种基金the Jiangsu Key Laboratory of Precision and Micro-Manufacturing Technology(No.JSKL2223K01)the Natural Science Foundation of Jiangsu Province(No.BK20210295)the Superior Postdoctoral Project of Jiangsu Province(No.2022ZB215)the Henan Science and Technology Public Relations Project(No.212102210445).
文摘The undeformed chip thickness and grinding force are key parameters for revealing the material removal mechanism in the grinding process.However,they are difficult to be well expressed due to the ununiformed protrusion height and random position distribution of abrasive grains on the abrasive wheel surface.This study investigated the distribution of undeformed chip thickness and grinding force considering the non-uniform characteristics of abrasive wheel in the grinding of K4002 nickel-based superalloy.First,a novel grinding force model was established through a kinematic-geometric analysis and a grain-workpiece contact analysis.Then,a series of grinding experiments were conducted for verifying the model.The results indicate that the distribution of undeformed chip thickness is highly consistent with the Gaussian distribution formula.The increase in the grinding depth mainly leads to an increase in the average value of Gaussian distribution.On the contrary,the increase in the workpiece infeed speed or the decrease in the grinding speed mainly increases the standard deviation of Gaussian distribution.The average and maximum errors of the grinding force model are 4.9%and 14.6%respectively,indicating that the model is of high predication accuracy.
基金supported by the National Natural Science Foundation of China(32171765)。
文摘While the fire protection function of tree bark has been extensively documented,other critical functions,including storage and mechanical support,have received less attention.In this study we examined:(1)the allometry of bark thickness(and biomass)against wood radius(and biomass)at a disc level,(2)differences in bark allocation between the ratio and the regression approaches,(3)differences between bark thickness and biomass as metrics of bark allocation,and(4)how bark allocation is associated with the evolution of wood from non-porous to diffuse-porous and ring-porous types.Thickness and biomass of bark and wood were measured using trunk discs of 88 individual trees of 36 species in a temperate forest characterized by a long fire interval.Allometric relationships of bark thickness(and biomass)against wood radius(and biomass)explained why both relative bark thickness and biomass decreased with increasing stem diameter.Variations in both among species varied by factors of 3.5 to 7.5 depending on the measurement methods.The ratio approach produced higher estimates of both relative bark thickness and biomass compared to the regression approach,while relative bark thickness was significantly lower than relative bark biomass.Ring-porous species exhibited higher bark thickness based on the ratio approach,which might reflect evolutionary adaptations where ring-porous species have developed thicker bark as protection:thermal insulation against freeze-thaw embolism coupled with carbohydrate reservoirs for hydraulic repair.The regression slope of bark allocation against wood density increased along the wood porosity gradient,demonstrating evolutionary biomechanical coordination between bark and wood.These findings highlight systematic coupling between bark and xylem multifunctionality.
基金supported by the National Natural Science Foundation of China(No.52074130)Engineering Research Center of Resource Utilization of Carbon-containing Waste with Carbon Neutrality,Ministry of Education,200237 Shanghai,PR China.
文摘To advance the understanding of the corrosion behavior of stainless steel bellows in marine atmospheric environments and enhance the precision of service life predictions,this study employs finite element simulations to investigate the pitting corrosion rates and pit morphologies of bellows peaks and troughs under varying electrolyte film thicknesses.The model incorporates localized electrochemical reactions,oxygen concentration,and homogeneous solution reactions.For improved computational accuracy,the fitted polarization curve data were directly applied as nonlinear boundary conditions on the electrode surface via interpolation functions.Simulation results reveal that the peak regions exhibit faster corrosion rates than the trough regions.With increasing electrolyte film thickness(from 10μm to 500μm),corrosion rates at both peaks and troughs decrease progressively,and after 120 hours of simulation,the maximum corrosion rate at the peaks declines from 0.720 mm/a to 0.130 mm/a,and at the troughs from 0.520 mm/a to 0.120 mm/a,with the disparity in corrosion rates diminishing over time.Furthermore,as corrosion progresses,pits propagate deeper into the substrate,exhibiting both vertical penetration and lateral expansion along the passive film interface,ultimately breaching the substrate.This research offers valuable insights into designing corrosion mitigation strategies for stainless steel bellows in marine environments.
基金supported by the National Natural Science Foundation of China(No.22422402)National Key Research and Development Program of China(No.2022YFF0705300)Key Research and Development Program of Jiangxi Province(No.20232BBG70004)。
文摘The performance and price of copper-based micro linear products are determined by the diameter uniformity.How to accurately detect the wire diameter of long-length copper based micro linear products without cutting or damage has always been a technical concern for production enterprises.Herein,a novel approach was developed for nondestructive detection of the average diameter at any given segment of a long copper wire by assessing the adsorption capacity of arginine on its surface.The amount of adsorbent on the surface of the copper wire exhibits a positive correlation with the area,which can be detected by extractive electrospray ionization mass spectrometry(EESI-MS)after online elution with ammonia.The experimental results demonstrated that the analysis can be completed within 15 min,with a good linear relationship between copper wires with different diameters and the adsorption capacity of arginine.The linear correlation coefficient R2was 0.995,the relative standard deviation was 1.10%-2.81%,and the detection limit reached 2.5μm(length of segment=4 cm),showing potential applications for facile measurement of the average diameter of various metal wires.
文摘BACKGROUND Despite growing evidence on endoscopic full thickness resection(EFTR),data on segment-specific outcomes in real-world patients remain limited.AIM To investigate segment-specific outcomes of EFTR using a full-thickness resection device(FTRD)for neoplastic colorectal lesions.METHODS In this multicenter,retrospective study,EFTR was conducted in unselected realworld patients referred to participating German centers after colonoscopy confirmed EFTR eligibility.The primary outcome was histologically complete resection(R0)of the lesion,including segment-specific outcomes and adverse events(AE).Additional efficacy and safety parameters were investigated by colonic topography for up to 30 days.RESULTS The analysis included 102 patients(64 males,38 females)with a median age of 70 years.EFTR via FTRD was technically successful in all patients.The R0 rate was 81.4%,segment-specifically ranging from 85.0%(rectum),84.6%(descending colon),84.0%(ascending colon),83.3%(cecum),and 76.5%(sigmoid colon)to 73.3%(transverse colon).Examination time was longer in proximal parts compared to the rectosigmoid(non-significant).Overall,33 patients(32.4%)experienced AE,including only one major complication(0.98%;perforation of sigmoid colon).Abdominal postsurgical pain(18.6%),hematochezia(9.8%),and hemoglobin decline(7.8%)were the most frequent minor complications.Transverse colon lesions had the numerically highest rate of AE,with 8 of 15 patients(53.3%)affected.CONCLUSION EFTR is efficacious for neoplastic colorectal lesions,though R0 rates vary by location.This may impact patient education,selection of the operator,and consideration of laparoscopy surgery.
基金supported by grants from National Natural Science Foundation of China(81720108012,82001118)Ministry of Science and Technology of China(2021ZD0202003)+1 种基金Shanghai‘Rising Stars of Medical Talents’Youth Development Program(SHWSRS(2023)-62)Henry K.Beecher Professorship from Harvard University。
文摘Background Postoperative delirium is one of the most common complications in the older surgical population,but its pathogenesis and biomarkers are largely undetermined.Retinal layer thickness has been demonstrated to be associated with cognitive function in mild cognitive impairment and patients with Alzheimer’s disease.However,relatively little is known about possible retinal layer thickness among patients with postoperative delirium.Aims We aimed to investigate the relationship between retinal layer thickness and postoperative delirium in this cross-sectional study.Methods The participants(≥65 years old)having elective surgery under general anaesthesia were screened via medical records from Shanghai 10th People’s Hospital.Preoperative macular thickness and peripapillary retinal nerve fibre layer(RNFL)thickness were measured using optical coherence tomography(OCT).The Confusion Assessment Method(CAM)algorithm and CAM-Severity(CAM-S)were used to assess the incidence and severity of postoperative delirium on the first,second and third days after surgery.Results Among 169 participants(mean(standard deviation(SD)71.15(4.36)years),40(24%)developed postoperative delirium.Notably,individuals who developed postoperative delirium exhibited thicker preoperative macular thickness in the right eye compared with those who did not(mean(SD)283.35(27.97)µm vs 273.84(20.14)µm,p=0.013).Furthermore,the thicker preoperative macular thickness of the right eye was associated with a higher incidence of postoperative delirium(adjusted odds ratio 1.593,95%confidence interval(CI)1.093 to 2.322,p=0.015)and greater severity(adjusted mean difference(β)=0.256,95%CI 0.037 to 0.476,p=0.022)after adjustment for age,sex and Mini-Mental State Examination(MMSE)scores.However,such a difference or association did not appear in the left macular or bilateral peripapillary RNFL thicknesses.Conclusions Current findings demonstrated that preoperative macular thickness might serve as a potential non-invasive marker for the vulnerability of developing postoperative delirium in older surgical patients.Further large-scale validation studies should be performed to confirm these results.
基金supported by the China Postdoctoral Science Foundation[Grant Number BX20240146 and 2024M761230]Key Project of Research and Development Plan in Jiangxi Province[Grant Number 20243BCC31001].
文摘Background Backfat thickness(BFT)is a vital economic trait in pigs,reflecting subcutaneous fat levels that affect meat quality and production efficiency.As a complex trait shaped by multiple genetic factors,BFT has been studied using genome-wide association studies(GWAS)and linkage analyses to locate fat-related quantitative trait loci(QTLs),but pinpointing causal variants and genes is hindered by linkage disequilibrium and limited regulatory data.This study aimed to dissect the QTLs affecting BFT on Sus scrofa chromosome 1(SSC1),elucidating regulatory variants,effector genes,and the cell types involved.Results Using whole-genome genotyping data from 3,578 pigs and phenotypic data for five BFT traits,we identified a 630.6 kb QTL on SSC1 significantly associated with these traits via GWAS and fine-mapping,pinpointing 34 candidate causal variants.Using deep convolutional neural networks to predict regulatory activity from sequence data integrated with detailed pig epigenetic profiles,we identified five SNPs potentially affecting enhancer activity in specific tissues.Notably,rs342950505(SSC1:161,123,588)influences weak enhancer activity across multiple tissues,including the brain.High-throughput chromosome conformation capture(Hi-C)analysis identified that rs342950505 interacts with eight genes.Chromatin state annotations confirmed enhancer activity at this QTL in the cerebellum.Leveraging these insights,single-cell ATAC-seq revealed a chromatin accessibility peak encompassing rs342950505 that regulates PMAIP1 expression in inhibitory neurons via enhancer-mediated mechanisms,with an adjacent peak modulating CCBE1 expression in neuroblasts and granule cells.Transcriptome-wide association studies(TWAS)confirmed PMAIP1's role in the hypothalamus,and Mendelian randomization(MR)validated PMAIP1 and CCBE1 as key brain expression quantitative trait locus(eQTL)effectors.We propose that the variant rs342950505,located within a regulatory peak,modulates PMAIP1 expression in inhibitory neurons,potentially influencing energy homeostasis via hypothalamic regulation.Similarly,CCBE1 may contribute to this process.Conclusions Our results,through systematic dissection of pleiotropic BFT-associated loci,provide a framework to elucidate regulatory mechanisms of complex traits,offering insights into polygenic control through lipid metabolism and neural signaling pathways.
基金financially supported by the National Natural Science Foundation of China(Grant Nos.92155305 and 42103066)the National Key Research and Development Plan(Grant No.2023YFC2908400 and 2024YFC2910102)the Fundamental Research Funds for the Central Universities(Grant No.FRF-TP-24-046A).
文摘The Qinghai-Tibet Plateau possesses the thickest continental crust on Earth,yet the timing of its formation remains debated.In this study,we conducted zircon U-Pb isotopic dating,geochemical and Sr-Nd-Pb-Hf isotopic analyses on the Xuexiumaer biotite quartz monzonite porphyry(BQMP)sampled from the Lake Dajia area in southern Gangdese.This study aims to estimate the paleo-crustal thickness beneath this region during the early India-Asia collision stage using whole-rock Sr/Y and(La/Yb)N ratios as proxies.Results reveal that the Xuexiumaer BQMP was formed at~51 Ma in a collisional tectonic setting following Neo-Tethyan slab breakoff,and is an I-type granitoid derived primarily from partial melting of juvenile mafic lower crust with subordinate ancient crustal input.The estimated paleo-crustal thickness in the Lake Dajia area at~51 Ma is less than 40 km.This indicates that although the Qinghai-Tibet Plateau had already undergone significant crustal thickening and attained an exceptionally thick crust(>50 km)prior to the India-Asia collision as demonstrated by previous studies,some regions still maintained a crust only slightly thicker than the average continental crust(~35 km)at the initial collision stage.This limited crustal thickening likely resulted from underplating of subduction-related mafic magma at the mantle-crust boundary.
