Born into a family of artisans,Pasang Degyi,a 20-someth ing in heritor of Tibetan embroidery,has dedicated herself to sustaining this 600-year-old intangible cultural heritage by weaving tradition into contemporary life.
In order to improve the threading stability and the head thickness precision in tandem hot rolling process, an adaptive threading strategy was proposed. The proposed strategy was realized by the rolling characteristic...In order to improve the threading stability and the head thickness precision in tandem hot rolling process, an adaptive threading strategy was proposed. The proposed strategy was realized by the rolling characteristics analysis, and factors which affect the rolling force and the final thickness were determined and analyzed based on the influence coefficients calculation process. An objective function consisting of the influenced factors was founded, and the disturbance quantity was obtained by minimizing the function with the Nelder-Mead simplex method, and the proposed adaptive threading strategy was realized based on the calculation results. The adaptive threading strategy has been applied to one 7-stand hot tandem mill successfully, actual statistics data show that the predicted rolling force prediction in the range of +/- 5.0% is improved to 97.8%, the head thickness precision in the range of +/- 35 mu m is improved to 98.5%, and the threading stability and the head thickness precision are enhanced to a high level.展开更多
We present a theory to simulate a coherent GaN QD with an adjacent pure edge threading dislocation by using a finite element method. The piezoelectric effects and the strain modified band edges are investigated in the...We present a theory to simulate a coherent GaN QD with an adjacent pure edge threading dislocation by using a finite element method. The piezoelectric effects and the strain modified band edges are investigated in the framework of multi-band κ · p theory to calculate the electron and the heavy hole energy levels. The linear optical absorption coefficients corresponding to the interband ground state transition are obtained via the density matrix approach and perturbation expansion method. The results indicate that the strain distribution of the threading dislocation affects the electronic structure. Moreover, the ground state transition behaviour is also influenced by the position of the adjacent threading dislocation.展开更多
Due to current technology enhancement,molecular databases have exponentially grown requesting faster efficient methods that can handle these amounts of huge data.There-fore,Multi-processing CPUs technology can be used...Due to current technology enhancement,molecular databases have exponentially grown requesting faster efficient methods that can handle these amounts of huge data.There-fore,Multi-processing CPUs technology can be used including physical and logical processors(Hyper Threading)to significantly increase the performance of computations.Accordingly,sequence comparison and pairwise alignment were both found contributing significantly in calculating the resemblance between sequences for constructing optimal alignments.This research used the Hash Table-NGram-Hirschberg(HT-NGH)algo-rithm to represent this pairwise alignment utilizing hashing capabilities.The authors propose using parallel shared memory architecture via Hyper Threading to improve the performance of molecular dataset protein pairwise alignment.The proposed parallel hyper threading method targeted the transformation of the HT-NGH on the datasets decomposition for sequence level efficient utilization within the processing units,that is,reducing idle processing unit situations.The authors combined hyper threading within the multicore architecture processing on shared memory utilization remarking perfor-mance of 24.8%average speed up to 34.4%as the highest boosting rate.The benefit of this work improvement is shown preserving acceptable accuracy,that is,reaching 2.08,2.88,and 3.87 boost-up as well as the efficiency of 1.04,0.96,and 0.97,using 2,3,and 4 cores,respectively,as attractive remarkable results.展开更多
Thickness deviation of hot strip rolling needs to be strictly controlled in the computer system. An adaptive threading technique was researched, in which the measured data from threaded stands were used to predict thi...Thickness deviation of hot strip rolling needs to be strictly controlled in the computer system. An adaptive threading technique was researched, in which the measured data from threaded stands were used to predict thickness and material hardness errors, to modify the setup for the remaining unthreaded stands. After the adaptive threading model was used online on the hot strip mill of the Panzhihua Iron and Steel Group Co Ltd, the thickness deviation was decreased obviously. The hit rate of thickness control of different steel grades increases.展开更多
The analysis of threading dislocation density (TDD) in Ge-on-Si layer is critical for developing lasers, light emitting diodes (LEDs), photodetectors (PDs), modulators, waveguides, metal oxide semiconductor fiel...The analysis of threading dislocation density (TDD) in Ge-on-Si layer is critical for developing lasers, light emitting diodes (LEDs), photodetectors (PDs), modulators, waveguides, metal oxide semiconductor field effect transistors (MOSFETs), and also the integration of Si-based monolithic photonics. The TDD of Ge epitaxial layer is analyzed by etching or transmission electron microscope (TEM). However, high-resolution x-ray diffraction (HR-XRD) rocking curve provides an optional method to analyze the TDD in Ge layer. The theory model of TDD measurement from rocking curves was first used in zinc-blende semiconductors. In this paper, this method is extended to the case of strained Ge-on-Si layers. The HR-XRD 2θ/ω scan is measured and Ge (004) single crystal rocking curve is utilized to calculate the TDD in strained Ge epitaxial layer. The rocking curve full width at half maximum (FWHM) broadening by incident beam divergence of the instrument, crystal size, and curvature of the crystal specimen is subtracted. The TDDs of samples A and B are calculated to be 1.41108 cm-2 and 6.47108 cm-2, respectively. In addition, we believe the TDDs calculated by this method to be the averaged dislocation density in the Ge epitaxial layer.展开更多
The threading dislocations(TDs)in GaAs/Si epitaxial layers due to the lattice mismatch seriously degrade the performance of the lasers grown on silicon.The insertion of InAs quantum dots(QDs)acting as dislocation filt...The threading dislocations(TDs)in GaAs/Si epitaxial layers due to the lattice mismatch seriously degrade the performance of the lasers grown on silicon.The insertion of InAs quantum dots(QDs)acting as dislocation filters is a pretty good alternative to solving this problem.In this paper,a finite element method(FEM)is proposed to calculate the critical condition for InAs/GaAs QDs bending TDs into interfacial misfit dislocations(MDs).Making a comparison of elastic strain energy between the two isolated systems,a reasonable result is obtained.The effect of the cap layer thickness and the base width of QDs on TD bending are studied,and the results show that the bending area ratio of single QD(the bending area divided by the area of the QD base)is evidently affected by the two factors.Moreover,we present a method to evaluate the bending capability of single-layer QDs and multi-layer QDs.For the QD with 24-nm base width and 5-nm cap layer thickness,taking the QD density of 1011 cm-2 into account,the bending area ratio of single-layer QDs(the area of bending TD divided by the area of QD layer)is about 38.71%.With inserting five-layer InAs QDs,the TD density decreases by 91.35%.The results offer the guidelines for designing the QD dislocation filters and provide an important step towards realizing the photonic integration circuits on silicon.展开更多
Transient fault detection mechanism is added to simultaneous multithreading architecture. By exploiting both ILP (Instruction Level Parallelism) and TLP (Thread Level Parallelism), Simultaneous Multithreading (SMT) Fa...Transient fault detection mechanism is added to simultaneous multithreading architecture. By exploiting both ILP (Instruction Level Parallelism) and TLP (Thread Level Parallelism), Simultaneous Multithreading (SMT) Fault Tolerance Processor can be expected to achieve better tradeoff between performance and hardware cost than traditional Fault Tolerance Processors. Detailed simulations of 3 of SPEC95 benchmarks show that executing two redundant programs on the fault-tolerant microarchitecture takes only 40%–61%longer than running a single version of the program. The new instruction fetch algorithm enhances the performance by 0.4%~1%to most of the benchmarks we choose randomly.展开更多
Alzheimer’s disease is a multi-amyloidosis disease characterized by amyloid-βdeposits in brain blood vessels,microaneurysms,and senile plaques.How amyloid-βdeposition affects axon pathology has not been examined ex...Alzheimer’s disease is a multi-amyloidosis disease characterized by amyloid-βdeposits in brain blood vessels,microaneurysms,and senile plaques.How amyloid-βdeposition affects axon pathology has not been examined extensively.We used immunohistochemistry and immunofluorescence staining to analyze the forebrain tissue slices of Alzheimer’s disease patients.Widespread axonal amyloidosis with distinctive axonal enlargement was observed in patients with Alzheimer’s disease.On average,amyloid-β-positive axon diameters in Alzheimer’s disease brains were 1.72 times those of control brain axons.Furthermore,axonal amyloidosis was associated with microtubule-associated protein 2 reduction,tau phosphorylation,lysosome destabilization,and several blood-related markers,such as apolipoprotein E,alpha-hemoglobin,glycosylated hemoglobin type A1C,and hemin.Lysosome destabilization in Alzheimer’s disease was also clearly identified in the neuronal soma,where it was associated with the co-expression of amyloid-β,Cathepsin D,alpha-hemoglobin,actin alpha 2,and collagen type IV.This suggests that exogenous hemorrhagic protein intake influences neural lysosome stability.Additionally,the data showed that amyloid-β-containing lysosomes were 2.23 times larger than control lysosomes.Furthermore,under rare conditions,axonal breakages were observed,which likely resulted in Wallerian degeneration.In summary,axonal enlargement associated with amyloidosis,micro-bleeding,and lysosome destabilization is a major defect in patients with Alzheimer’s disease.This finding suggests that,in addition to the well-documented neural soma and synaptic damage,axonal damage is a key component of neuronal defects in Alzheimer’s disease.展开更多
The growth process of three-dimensional growth mode(3D) switching to two-dimensional growth mode (2D) is investigated when GaN films are grown on cone-shaped patterned sapphire substrates by metal-organic chemical...The growth process of three-dimensional growth mode(3D) switching to two-dimensional growth mode (2D) is investigated when GaN films are grown on cone-shaped patterned sapphire substrates by metal-organic chemical vapor deposition.The growth condition of the 3D-2D growth process is optimized to reduce the threading dislocation density(TDD).It is found that the condition of the 3D layer is critical.The 3D layer keeps growing under the conditions of lowⅤ/Ⅲratio,low temperature,and high pressure until its thickness is comparable to the height of the cone-shaped patterns.Then the 3D layer surrounds the cone-shaped patterns and has inclined side facets and a top(0001) plane.In the following 2D-growth process,inclined side facets coalesce quickly and the interaction of TDs with the side facets causes the TDs to bend over.As a result,the TDD of GaN films can decrease to 1×10~8 cm^(-2),giving full-width at half maximum values of 211 and 219 arcsec for(002) and(102) omega scans, respectively.展开更多
Threaded connection is a common structural form in mechanical engineering,with their complex nonlinear behavior under combined loading critically affecting structural performance.While existing simplified models and f...Threaded connection is a common structural form in mechanical engineering,with their complex nonlinear behavior under combined loading critically affecting structural performance.While existing simplified models and finite element analysis(FEA)methods describe force distribution under single loading conditions,accurately modeling threaded connections under complex loading remains challenging.This paper proposes a simplified theoretical model to efficiently predict contact forces and deformation distributions under tension,torsion,bending,and shear.The model treats bolt and nut bodies as Euler-Bernoulli beams and represents thread stiffness using equivalent trapezoidal cantilever beams,reducing computational complexity while retaining essential mechanical characteristics.The paper introduces reference helical curves and derives a deformation coordination relationship based on contact constraints.The model’s calculations are validated against FEA results,demonstrating both high precision and significant computational efficiency under complex loading conditions.This work provides an efficient and reliable tool for analyzing threaded connections,offering promising engineering applications.展开更多
GaN epifilms are grown on the patterned sapphire substrates(PSS)(0001)and the conventional sapphire substrates(CSS)(0001)by metal-organic chemical vapor deposition(MOCVD)using a novel two-step growth.High resolution X...GaN epifilms are grown on the patterned sapphire substrates(PSS)(0001)and the conventional sapphire substrates(CSS)(0001)by metal-organic chemical vapor deposition(MOCVD)using a novel two-step growth.High resolution X-ray diffraction(HR-XRD)is used to investigate the threading dislocation(TD)density of the GaN epifilms.The TD density is calculated from theω-scans full width at half maximum(FWHM)results of HR-XRD.The edge dislocation destiny of GaN grown on the PSS is 2.7×108 cm-2,which is less than on the CSS.This is confirmed by the results of atomic force microscopy(AFM)measurement.The lower TD destiny indicates that the crystalline quality of the GaN epifilms grown on the PSS is improved compared to GaN epifilms grown on the CSS.The residual strains of GaN grown on the PSS and CSS are compared by Raman Scattering spectra.It is clearly seen that the residual strain in the GaN grown on PSS is lower than on the CSS.展开更多
Thread partition plays an important role in speculative multithreading (SpMT) for automatic parallelization of ir- regular programs. Using unified values of partition parameters to partition different applications l...Thread partition plays an important role in speculative multithreading (SpMT) for automatic parallelization of ir- regular programs. Using unified values of partition parameters to partition different applications leads to the fact that every ap- plication cannot own its optimal partition scheme. In this paper, five parameters affecting thread partition are extracted from heuristic rules. They are the dependence threshold (DT), lower limit of thread size (TSL), upper limit of thread size (TSU), lower limit of spawning distance (SDL), and upper limit of spawning distance (SDU). Their ranges are determined in accordance with heuristic rules, and their step-sizes are set empirically. Under the condition of setting speedup as an objective function, all com- binations of five threshold values form the solution space, and our aim is to search for the best combination to obtain the best thread granularity, thread dependence, and spawning distance, so that every application has its best partition scheme. The issue can be attributed to a single objective optimization problem. We use the artificial immune algorithm (AIA) to search for the optimal solution. On Prophet, which is a generic SpMT processor to evaluate the performance of multithreaded programs, Olden bench- marks are used to implement the process. Experiments show that we can obtain the optimal parameter values for every benchmark, and Olden benchmarks partitioned with the optimized parameter values deliver a performance improvement of 3.00% on a 4-core platform compared with a machine learning based approach, and 8.92% compared with a heuristics-based approach.展开更多
The symbiotic nitrogen fixation process between legume roots and rhizobia initiates at the root hairs.Rhizobia initially colonize the tip of the root hairs and induce its curling to become entrapped.However,the specif...The symbiotic nitrogen fixation process between legume roots and rhizobia initiates at the root hairs.Rhizobia initially colonize the tip of the root hairs and induce its curling to become entrapped.However,the specific molecular mechanisms underlying root hair deformation and curling in response to rhizobial infection remain unclear.In this study,transcriptome analysis of wild-type JiMa389 and nodulation-deficient mutant jima61 of Melilotus albus,the Rho-like small GTPase MaROP10.Our results show that MaROP10 functions as an interacts with the Nod factor receptor NFR5 to regulate rhizobiainduced root hair deformation and infection thread formation during the early stages of rhizobial infection.To elucidate the mechanism of MaROP10,we further identified its downstream potential effector protein,MaRIC6,which positively regulates root hair deformation and infection thread formation.Taken together,MaROP10 likely integrates signals from the symbiotic receptor NFR5 to regulate downstream signaling pathways through its effector MaRIC6,thereby coordinating root hair deformation and infection thread development during the early stages of rhizobial infection.展开更多
The evolution of next-generation district heating networks toward higher efficiency and sustainability is constrained by persistent challenges in supply-demand coordination and lifecycle optimization.This paper provid...The evolution of next-generation district heating networks toward higher efficiency and sustainability is constrained by persistent challenges in supply-demand coordination and lifecycle optimization.This paper provides a comprehensive review of artificial intelligence(AI)integration across four key lifecycle stages of heating networks:planning and design,construction and renewal,operation and control,as well as maintenance and fault diagnosis.Critical research gaps are identified,including application fragmentation and persistent data silos.The literature has demonstrated that AI-based approaches can deliver significant performance improvements across multiple lifecycle stages.In the planning phase,AI can improve design computational efficiency,in some cases by up to an order of magnitude.In the construction phase,AI-enhanced management has been shown to accelerate project timelines while reducing costs.For operational control,deep learning models can reduce thermal load forecasting errors by more than half.In the maintenance phase,AI enables multiday early fault warnings with localization accuracies exceeding 95%in representative studies.To address the limitations of fragmented applications,a digital thread framework is proposed to enable cross-lifecycle data continuity and integration of decision-making across engineering phase.Finally,future research directions are outlined,emphasizing adaptive AI frameworks aligned with urban evolution,the integration of digital twins with intelligent optimization agents,and the development of interpretable and transferable AI models.展开更多
BACKGROUND Anal fistula is a common anorectal disorder,for which incision and thread hanging(ITH)remains a widely used treatment.However,ITH is often associated with substantial postoperative discomfort and carries a ...BACKGROUND Anal fistula is a common anorectal disorder,for which incision and thread hanging(ITH)remains a widely used treatment.However,ITH is often associated with substantial postoperative discomfort and carries a risk of anal sphincter injury,potentially compromising functional outcomes.The anal fistula clip(AFC)is a novel surgical technique designed to occlude the internal orifice of the fistula,eliminate infection source,and preserve anal sphincter function.AIM To compare the efficacy and safety between AFC and ITH in a randomized,single-center study focusing on short-term postoperative outcomes.METHODS A total of 70 patients with anal fistula who underwent surgery from August 2019 to January 2025 were randomly assigned to the ITH or AFC group.The primary outcomes included cure rates,pain scores,anal sphincter function,and complications.Patients were followed up postoperatively for 6 months.RESULTS All surgeries were successfully performed,with postoperative cure rates exceeding 90%in both groups.No severe complications or postoperative fecal incontinence occurred.Compared with the ITH group,the AFC group demonstrated better outcomes in early postoperative pain(P<0.01),wound healing time(P<0.01),and anal sphincter function preservation(P<0.05).CONCLUSION Compared with ITH,AFC may reduce postoperative pain,shorten healing time,preserve function,and minimize complications.AFC may be safe and effective;however,larger studies with longer follow-up are needed.展开更多
Effective spatial data maintenance during the operation and maintenance phase of airports is imperative for the infrastructure safety,operational effectiveness,and compliance with regulations.However,airports encounte...Effective spatial data maintenance during the operation and maintenance phase of airports is imperative for the infrastructure safety,operational effectiveness,and compliance with regulations.However,airports encounter serious challenges such as lack of management support,insufficient funding,and poor-quality data sources.Despite the recognised potential of emerging technologies such as digital twins,digital threads,ontologies,scalable data architectures,and governance frameworks,their integrated application for airport spatial data management remains unexplored.The existing literature focuses on analysing these technologies individually,leaving a large gap for their combined application for end-to-end comprehensive spatial data maintenance.To bridge this gap,this research proposes a comprehensive,literature-based framework using qualitative research as the underlying approach with the inclusion of a comprehensive literature review,and semi-structured interviews with experts for practical significance and theoretical richness.By employing inductive thematic analysis,we identified critical drivers and challenges in the practice of spatial data maintenance.The proposed framework brings together digital twins for realistic infrastructure simulation,digital threads for end-to-end data traceability,ontologies for semantic interoperability,data lakehouses for cost-optimisation,and a governance layer for compliance and data integrity.The integrated ecosystem addresses the identified challenges by leveraging the identified drivers and technological synergies,enhancing data-driven decision-making capabilities across diversified airport settings.Although the proposed framework is theoretically validated,it must be tested on real airports,representing a critical limitation.Additionally,the scope of the research is constrained by stakeholder insights primarily from medium-sized U.S.airports,which may limit applicability for large airports or other regulatory frameworks.Future research will involve piloting the framework for empirical testing of performance and adaptability,enhancing stakeholder engagement across the world,examining the strategies for mainstreaming with existing airport systems,and addressing ethical and cybersecurity issues.展开更多
The J55 tubing thread fastener in an electric pump well experienced corrosion failure.The causes of the failure were investigated through physical and chemical property tests,corrosion product analysis,and microbial a...The J55 tubing thread fastener in an electric pump well experienced corrosion failure.The causes of the failure were investigated through physical and chemical property tests,corrosion product analysis,and microbial analysis.The results show that the metallographic structure and composition of the J55 tubing were normal.CO 2 corrosion was not the main cause of the thread fastener failure.The actual cause of the corrosion failure was microbiological corrosion,such as sulfate-reducing bacteria,thiosulfate-reducing bacteria,and iron-oxidizing bacteria.展开更多
E-commerce has transformed Caoxian into a hub of traditional Chinese attire.STEPPING inside Caoxian’s Youai Cloud Warehouse,a livestreaming base dedicated to hanfu(traditional clothing),it feels less like a clothing ...E-commerce has transformed Caoxian into a hub of traditional Chinese attire.STEPPING inside Caoxian’s Youai Cloud Warehouse,a livestreaming base dedicated to hanfu(traditional clothing),it feels less like a clothing warehouse and more like a time capsule.Thousands of intricately embroidered garments line the racks-from elegant horse-face skirts to modernised editions of traditional Chinese clothing.展开更多
In a busy knitting workshop in Yiwu,Zhejiang Province,nearly 100 warp knitting machines hum in unison.Suddenly,one of them stops.The reason is almost imperceptible:a single polyester thread has snapped.
摘要Born into a family of artisans,Pasang Degyi,a 20-someth ing in heritor of Tibetan embroidery,has dedicated herself to sustaining this 600-year-old intangible cultural heritage by weaving tradition into contemporary life.
基金Project(51504061)supported by the National Natural Science Foundation of China
摘要In order to improve the threading stability and the head thickness precision in tandem hot rolling process, an adaptive threading strategy was proposed. The proposed strategy was realized by the rolling characteristics analysis, and factors which affect the rolling force and the final thickness were determined and analyzed based on the influence coefficients calculation process. An objective function consisting of the influenced factors was founded, and the disturbance quantity was obtained by minimizing the function with the Nelder-Mead simplex method, and the proposed adaptive threading strategy was realized based on the calculation results. The adaptive threading strategy has been applied to one 7-stand hot tandem mill successfully, actual statistics data show that the predicted rolling force prediction in the range of +/- 5.0% is improved to 97.8%, the head thickness precision in the range of +/- 35 mu m is improved to 98.5%, and the threading stability and the head thickness precision are enhanced to a high level.
基金Project supported by the National High Technology Research and Development Program of China(Grant No.2009AA03Z405)the National Natural Science Foundation of China(Grant Nos.60908028 and 60971068)+1 种基金the High School Innovation and Introducing Talent Project of China(Grant No.B07005)the Chinese Universities Scientific Fund(Grant No.BUPT2009RC0412)
摘要We present a theory to simulate a coherent GaN QD with an adjacent pure edge threading dislocation by using a finite element method. The piezoelectric effects and the strain modified band edges are investigated in the framework of multi-band κ · p theory to calculate the electron and the heavy hole energy levels. The linear optical absorption coefficients corresponding to the interband ground state transition are obtained via the density matrix approach and perturbation expansion method. The results indicate that the strain distribution of the threading dislocation affects the electronic structure. Moreover, the ground state transition behaviour is also influenced by the position of the adjacent threading dislocation.
基金Deanship of Scientific Research(DSR),King Abdulaziz University,Grant/Award Number:D-139-137-1441。
摘要Due to current technology enhancement,molecular databases have exponentially grown requesting faster efficient methods that can handle these amounts of huge data.There-fore,Multi-processing CPUs technology can be used including physical and logical processors(Hyper Threading)to significantly increase the performance of computations.Accordingly,sequence comparison and pairwise alignment were both found contributing significantly in calculating the resemblance between sequences for constructing optimal alignments.This research used the Hash Table-NGram-Hirschberg(HT-NGH)algo-rithm to represent this pairwise alignment utilizing hashing capabilities.The authors propose using parallel shared memory architecture via Hyper Threading to improve the performance of molecular dataset protein pairwise alignment.The proposed parallel hyper threading method targeted the transformation of the HT-NGH on the datasets decomposition for sequence level efficient utilization within the processing units,that is,reducing idle processing unit situations.The authors combined hyper threading within the multicore architecture processing on shared memory utilization remarking perfor-mance of 24.8%average speed up to 34.4%as the highest boosting rate.The benefit of this work improvement is shown preserving acceptable accuracy,that is,reaching 2.08,2.88,and 3.87 boost-up as well as the efficiency of 1.04,0.96,and 0.97,using 2,3,and 4 cores,respectively,as attractive remarkable results.
基金National Natural Science Foundation of China (50104004)
摘要Thickness deviation of hot strip rolling needs to be strictly controlled in the computer system. An adaptive threading technique was researched, in which the measured data from threaded stands were used to predict thickness and material hardness errors, to modify the setup for the remaining unthreaded stands. After the adaptive threading model was used online on the hot strip mill of the Panzhihua Iron and Steel Group Co Ltd, the thickness deviation was decreased obviously. The hit rate of thickness control of different steel grades increases.
基金Project supported by the Research Plan in Shaanxi Province,China(Grant No.2016GY-085)the Opening Project of Key Laboratory of Microelectronic Devices&Integrated Technology,Institute of Microelectronics,Chinese Academy of Sciences(Grant No.90109162905)+1 种基金the Fundamental Research Funds for the Central Universities(Grant No.17-H863-04-ZT-001-019-01)the National Natural Science Foundation of China(Grant Nos.61704130 and 61474085)
摘要The analysis of threading dislocation density (TDD) in Ge-on-Si layer is critical for developing lasers, light emitting diodes (LEDs), photodetectors (PDs), modulators, waveguides, metal oxide semiconductor field effect transistors (MOSFETs), and also the integration of Si-based monolithic photonics. The TDD of Ge epitaxial layer is analyzed by etching or transmission electron microscope (TEM). However, high-resolution x-ray diffraction (HR-XRD) rocking curve provides an optional method to analyze the TDD in Ge layer. The theory model of TDD measurement from rocking curves was first used in zinc-blende semiconductors. In this paper, this method is extended to the case of strained Ge-on-Si layers. The HR-XRD 2θ/ω scan is measured and Ge (004) single crystal rocking curve is utilized to calculate the TDD in strained Ge epitaxial layer. The rocking curve full width at half maximum (FWHM) broadening by incident beam divergence of the instrument, crystal size, and curvature of the crystal specimen is subtracted. The TDDs of samples A and B are calculated to be 1.41108 cm-2 and 6.47108 cm-2, respectively. In addition, we believe the TDDs calculated by this method to be the averaged dislocation density in the Ge epitaxial layer.
基金Project supported by the National Natural Science Foundation of China(Grant Nos.61874148,61974141,and 61674020)the Beijing Natural Science Foundation,China(Grant No.4192043)+3 种基金the National Key Research and Development Program of China(Grant No.2018YFB2200104)the Fund from the Beijing Municipal Science&Technology Commission,China(Grant No.Z191100004819012)the Project of the State Key Laboratory of Information Photonics and Optical Communications,Beijing University of Posts and Telecommunications,China(Grant No.IPOC2018ZT01)the 111 Project of China(Grant No.B07005).
摘要The threading dislocations(TDs)in GaAs/Si epitaxial layers due to the lattice mismatch seriously degrade the performance of the lasers grown on silicon.The insertion of InAs quantum dots(QDs)acting as dislocation filters is a pretty good alternative to solving this problem.In this paper,a finite element method(FEM)is proposed to calculate the critical condition for InAs/GaAs QDs bending TDs into interfacial misfit dislocations(MDs).Making a comparison of elastic strain energy between the two isolated systems,a reasonable result is obtained.The effect of the cap layer thickness and the base width of QDs on TD bending are studied,and the results show that the bending area ratio of single QD(the bending area divided by the area of the QD base)is evidently affected by the two factors.Moreover,we present a method to evaluate the bending capability of single-layer QDs and multi-layer QDs.For the QD with 24-nm base width and 5-nm cap layer thickness,taking the QD density of 1011 cm-2 into account,the bending area ratio of single-layer QDs(the area of bending TD divided by the area of QD layer)is about 38.71%.With inserting five-layer InAs QDs,the TD density decreases by 91.35%.The results offer the guidelines for designing the QD dislocation filters and provide an important step towards realizing the photonic integration circuits on silicon.
基金Supported by the National Natural Science Funda tion of China (60103002)
摘要Transient fault detection mechanism is added to simultaneous multithreading architecture. By exploiting both ILP (Instruction Level Parallelism) and TLP (Thread Level Parallelism), Simultaneous Multithreading (SMT) Fault Tolerance Processor can be expected to achieve better tradeoff between performance and hardware cost than traditional Fault Tolerance Processors. Detailed simulations of 3 of SPEC95 benchmarks show that executing two redundant programs on the fault-tolerant microarchitecture takes only 40%–61%longer than running a single version of the program. The new instruction fetch algorithm enhances the performance by 0.4%~1%to most of the benchmarks we choose randomly.
基金supported by the National Natural Science Foundation of China,No.81472235(to HF)the Shanghai Jiao Tong University Medical and Engineering Project,Nos.YG2021QN53(to HF),YG2017MS71(to HF)+1 种基金the International Cooperation Project of the National Natural Science Foundation of China,No.82020108017(to DC)the Innovation Group Project of the National Natural Science Foundation of China,No.81921002(to DC).
摘要Alzheimer’s disease is a multi-amyloidosis disease characterized by amyloid-βdeposits in brain blood vessels,microaneurysms,and senile plaques.How amyloid-βdeposition affects axon pathology has not been examined extensively.We used immunohistochemistry and immunofluorescence staining to analyze the forebrain tissue slices of Alzheimer’s disease patients.Widespread axonal amyloidosis with distinctive axonal enlargement was observed in patients with Alzheimer’s disease.On average,amyloid-β-positive axon diameters in Alzheimer’s disease brains were 1.72 times those of control brain axons.Furthermore,axonal amyloidosis was associated with microtubule-associated protein 2 reduction,tau phosphorylation,lysosome destabilization,and several blood-related markers,such as apolipoprotein E,alpha-hemoglobin,glycosylated hemoglobin type A1C,and hemin.Lysosome destabilization in Alzheimer’s disease was also clearly identified in the neuronal soma,where it was associated with the co-expression of amyloid-β,Cathepsin D,alpha-hemoglobin,actin alpha 2,and collagen type IV.This suggests that exogenous hemorrhagic protein intake influences neural lysosome stability.Additionally,the data showed that amyloid-β-containing lysosomes were 2.23 times larger than control lysosomes.Furthermore,under rare conditions,axonal breakages were observed,which likely resulted in Wallerian degeneration.In summary,axonal enlargement associated with amyloidosis,micro-bleeding,and lysosome destabilization is a major defect in patients with Alzheimer’s disease.This finding suggests that,in addition to the well-documented neural soma and synaptic damage,axonal damage is a key component of neuronal defects in Alzheimer’s disease.
摘要The growth process of three-dimensional growth mode(3D) switching to two-dimensional growth mode (2D) is investigated when GaN films are grown on cone-shaped patterned sapphire substrates by metal-organic chemical vapor deposition.The growth condition of the 3D-2D growth process is optimized to reduce the threading dislocation density(TDD).It is found that the condition of the 3D layer is critical.The 3D layer keeps growing under the conditions of lowⅤ/Ⅲratio,low temperature,and high pressure until its thickness is comparable to the height of the cone-shaped patterns.Then the 3D layer surrounds the cone-shaped patterns and has inclined side facets and a top(0001) plane.In the following 2D-growth process,inclined side facets coalesce quickly and the interaction of TDs with the side facets causes the TDs to bend over.As a result,the TDD of GaN films can decrease to 1×10~8 cm^(-2),giving full-width at half maximum values of 211 and 219 arcsec for(002) and(102) omega scans, respectively.
基金supported by the National Natural Science Foundation of China(Grant Nos.11932001,U2241264,and 12272003).
摘要Threaded connection is a common structural form in mechanical engineering,with their complex nonlinear behavior under combined loading critically affecting structural performance.While existing simplified models and finite element analysis(FEA)methods describe force distribution under single loading conditions,accurately modeling threaded connections under complex loading remains challenging.This paper proposes a simplified theoretical model to efficiently predict contact forces and deformation distributions under tension,torsion,bending,and shear.The model treats bolt and nut bodies as Euler-Bernoulli beams and represents thread stiffness using equivalent trapezoidal cantilever beams,reducing computational complexity while retaining essential mechanical characteristics.The paper introduces reference helical curves and derives a deformation coordination relationship based on contact constraints.The model’s calculations are validated against FEA results,demonstrating both high precision and significant computational efficiency under complex loading conditions.This work provides an efficient and reliable tool for analyzing threaded connections,offering promising engineering applications.
基金support from the National Natural Science Foundation of China(Grant Nos.60877006 and 50872146)
摘要GaN epifilms are grown on the patterned sapphire substrates(PSS)(0001)and the conventional sapphire substrates(CSS)(0001)by metal-organic chemical vapor deposition(MOCVD)using a novel two-step growth.High resolution X-ray diffraction(HR-XRD)is used to investigate the threading dislocation(TD)density of the GaN epifilms.The TD density is calculated from theω-scans full width at half maximum(FWHM)results of HR-XRD.The edge dislocation destiny of GaN grown on the PSS is 2.7×108 cm-2,which is less than on the CSS.This is confirmed by the results of atomic force microscopy(AFM)measurement.The lower TD destiny indicates that the crystalline quality of the GaN epifilms grown on the PSS is improved compared to GaN epifilms grown on the CSS.The residual strains of GaN grown on the PSS and CSS are compared by Raman Scattering spectra.It is clearly seen that the residual strain in the GaN grown on PSS is lower than on the CSS.
基金supported by the National Natural Science Foundation of China(No.61173040)the Doctoral Fund of Ministry of Education of China(No.2013021110012)
摘要Thread partition plays an important role in speculative multithreading (SpMT) for automatic parallelization of ir- regular programs. Using unified values of partition parameters to partition different applications leads to the fact that every ap- plication cannot own its optimal partition scheme. In this paper, five parameters affecting thread partition are extracted from heuristic rules. They are the dependence threshold (DT), lower limit of thread size (TSL), upper limit of thread size (TSU), lower limit of spawning distance (SDL), and upper limit of spawning distance (SDU). Their ranges are determined in accordance with heuristic rules, and their step-sizes are set empirically. Under the condition of setting speedup as an objective function, all com- binations of five threshold values form the solution space, and our aim is to search for the best combination to obtain the best thread granularity, thread dependence, and spawning distance, so that every application has its best partition scheme. The issue can be attributed to a single objective optimization problem. We use the artificial immune algorithm (AIA) to search for the optimal solution. On Prophet, which is a generic SpMT processor to evaluate the performance of multithreaded programs, Olden bench- marks are used to implement the process. Experiments show that we can obtain the optimal parameter values for every benchmark, and Olden benchmarks partitioned with the optimized parameter values deliver a performance improvement of 3.00% on a 4-core platform compared with a machine learning based approach, and 8.92% compared with a heuristics-based approach.
基金supported by the National Natural Science Foundation of China(U23A200216)Inner Mongolia Seed Industry Science and Technology Innovation Major Demonstration Project(2022JBGS0040)Gansu Provincial Science and Technology Plan Project(23ZDKA013)。
摘要The symbiotic nitrogen fixation process between legume roots and rhizobia initiates at the root hairs.Rhizobia initially colonize the tip of the root hairs and induce its curling to become entrapped.However,the specific molecular mechanisms underlying root hair deformation and curling in response to rhizobial infection remain unclear.In this study,transcriptome analysis of wild-type JiMa389 and nodulation-deficient mutant jima61 of Melilotus albus,the Rho-like small GTPase MaROP10.Our results show that MaROP10 functions as an interacts with the Nod factor receptor NFR5 to regulate rhizobiainduced root hair deformation and infection thread formation during the early stages of rhizobial infection.To elucidate the mechanism of MaROP10,we further identified its downstream potential effector protein,MaRIC6,which positively regulates root hair deformation and infection thread formation.Taken together,MaROP10 likely integrates signals from the symbiotic receptor NFR5 to regulate downstream signaling pathways through its effector MaRIC6,thereby coordinating root hair deformation and infection thread development during the early stages of rhizobial infection.
基金supported by the National Key R&D Program of China(No.2024YFB4206500)the“Pioneer”and“Leading Goose”R&D Program of Zhejiang Province(No.2025C02237)China,and the Foundation of the Key Laboratory of Cleaner Intelligent Control on Coal&Electricity,Ministry of Educa‐tion(No.CICCE202510),China。
摘要The evolution of next-generation district heating networks toward higher efficiency and sustainability is constrained by persistent challenges in supply-demand coordination and lifecycle optimization.This paper provides a comprehensive review of artificial intelligence(AI)integration across four key lifecycle stages of heating networks:planning and design,construction and renewal,operation and control,as well as maintenance and fault diagnosis.Critical research gaps are identified,including application fragmentation and persistent data silos.The literature has demonstrated that AI-based approaches can deliver significant performance improvements across multiple lifecycle stages.In the planning phase,AI can improve design computational efficiency,in some cases by up to an order of magnitude.In the construction phase,AI-enhanced management has been shown to accelerate project timelines while reducing costs.For operational control,deep learning models can reduce thermal load forecasting errors by more than half.In the maintenance phase,AI enables multiday early fault warnings with localization accuracies exceeding 95%in representative studies.To address the limitations of fragmented applications,a digital thread framework is proposed to enable cross-lifecycle data continuity and integration of decision-making across engineering phase.Finally,future research directions are outlined,emphasizing adaptive AI frameworks aligned with urban evolution,the integration of digital twins with intelligent optimization agents,and the development of interpretable and transferable AI models.
基金Supported by Natural Science Foundation of Anhui Province,No.2408085MH227Chinese Medicine Advantageous Specialty Project of Anhui Province+1 种基金Clinical Medical Research Transformation Project of Anhui Province,No.202427b10020014Clinical Research Foundation of Anhui University of Chinese Medicine,No.2020yfyzc42.
摘要BACKGROUND Anal fistula is a common anorectal disorder,for which incision and thread hanging(ITH)remains a widely used treatment.However,ITH is often associated with substantial postoperative discomfort and carries a risk of anal sphincter injury,potentially compromising functional outcomes.The anal fistula clip(AFC)is a novel surgical technique designed to occlude the internal orifice of the fistula,eliminate infection source,and preserve anal sphincter function.AIM To compare the efficacy and safety between AFC and ITH in a randomized,single-center study focusing on short-term postoperative outcomes.METHODS A total of 70 patients with anal fistula who underwent surgery from August 2019 to January 2025 were randomly assigned to the ITH or AFC group.The primary outcomes included cure rates,pain scores,anal sphincter function,and complications.Patients were followed up postoperatively for 6 months.RESULTS All surgeries were successfully performed,with postoperative cure rates exceeding 90%in both groups.No severe complications or postoperative fecal incontinence occurred.Compared with the ITH group,the AFC group demonstrated better outcomes in early postoperative pain(P<0.01),wound healing time(P<0.01),and anal sphincter function preservation(P<0.05).CONCLUSION Compared with ITH,AFC may reduce postoperative pain,shorten healing time,preserve function,and minimize complications.AFC may be safe and effective;however,larger studies with longer follow-up are needed.
摘要Effective spatial data maintenance during the operation and maintenance phase of airports is imperative for the infrastructure safety,operational effectiveness,and compliance with regulations.However,airports encounter serious challenges such as lack of management support,insufficient funding,and poor-quality data sources.Despite the recognised potential of emerging technologies such as digital twins,digital threads,ontologies,scalable data architectures,and governance frameworks,their integrated application for airport spatial data management remains unexplored.The existing literature focuses on analysing these technologies individually,leaving a large gap for their combined application for end-to-end comprehensive spatial data maintenance.To bridge this gap,this research proposes a comprehensive,literature-based framework using qualitative research as the underlying approach with the inclusion of a comprehensive literature review,and semi-structured interviews with experts for practical significance and theoretical richness.By employing inductive thematic analysis,we identified critical drivers and challenges in the practice of spatial data maintenance.The proposed framework brings together digital twins for realistic infrastructure simulation,digital threads for end-to-end data traceability,ontologies for semantic interoperability,data lakehouses for cost-optimisation,and a governance layer for compliance and data integrity.The integrated ecosystem addresses the identified challenges by leveraging the identified drivers and technological synergies,enhancing data-driven decision-making capabilities across diversified airport settings.Although the proposed framework is theoretically validated,it must be tested on real airports,representing a critical limitation.Additionally,the scope of the research is constrained by stakeholder insights primarily from medium-sized U.S.airports,which may limit applicability for large airports or other regulatory frameworks.Future research will involve piloting the framework for empirical testing of performance and adaptability,enhancing stakeholder engagement across the world,examining the strategies for mainstreaming with existing airport systems,and addressing ethical and cybersecurity issues.
摘要The J55 tubing thread fastener in an electric pump well experienced corrosion failure.The causes of the failure were investigated through physical and chemical property tests,corrosion product analysis,and microbial analysis.The results show that the metallographic structure and composition of the J55 tubing were normal.CO 2 corrosion was not the main cause of the thread fastener failure.The actual cause of the corrosion failure was microbiological corrosion,such as sulfate-reducing bacteria,thiosulfate-reducing bacteria,and iron-oxidizing bacteria.
摘要E-commerce has transformed Caoxian into a hub of traditional Chinese attire.STEPPING inside Caoxian’s Youai Cloud Warehouse,a livestreaming base dedicated to hanfu(traditional clothing),it feels less like a clothing warehouse and more like a time capsule.Thousands of intricately embroidered garments line the racks-from elegant horse-face skirts to modernised editions of traditional Chinese clothing.
摘要In a busy knitting workshop in Yiwu,Zhejiang Province,nearly 100 warp knitting machines hum in unison.Suddenly,one of them stops.The reason is almost imperceptible:a single polyester thread has snapped.