The association between inflammatory bowel disease(IBD) and colorectal cancer(CRC) has been recognised since 1925 and still accounts for 10%-15% of deaths in IBD.IBD-associated CRC(IBD-CRC) affects patients at a young...The association between inflammatory bowel disease(IBD) and colorectal cancer(CRC) has been recognised since 1925 and still accounts for 10%-15% of deaths in IBD.IBD-associated CRC(IBD-CRC) affects patients at a younger age than sporadic CRC.The prognosis for sporadic CRC and IBD-CRC is similar,with a 5-year survival of approximately 50%.Identifying at risk patients and implementing appropriate surveillance for these patients is central to managing the CRC risk in IBD.The increased risk of colorectal cancer in association with IBD is thought to be due to genetic and acquired factors.The link between inflammation and cancer is well recognised but the molecular biology,immune pathobiology and genetics of IBD-CRC are areas of much ongoing research.This review examines the literature relating to IBD-CRC,focusing on the incidence of IBD-CRC and examining potential risk factors including age at diagnosis,gender,duration and extent of colitis,severity of inflammation,family history of sporadic CRC and co-existent primary sclerosing cholangitis(PSC).Confirmed risk factors for IBD-CRC are duration,severity and extent of colitis,the presence of co-existent PSC and a family history of CRC.There is insufficient evidence currently to support an increased frequency of surveillance for patients diagnosed with IBD at a younger age.Evidence-based guidelines advise surveillance colonoscopy for patients with colitis 8 to 10 years after diagnosis,with the interval for further surveillance guided by risk factors(extent of disease,family history of CRC,post-inflammatory polyps,concomitant PSC,personal history of colonic dysplasia,colonic strictures).There is a move away from using random colonic biopsies towards targeted biopsies aimed at abnormal areas identified by newer colonoscopic techniques(narrow band imaging,chromoendoscopy,confocal microendoscopy).展开更多
Because China is becoming an aging society,the incidence of diabetes and diabetic foot have been increasing.Diabetic foot has become one of the main health-related killers due to its high disability and mortality rate...Because China is becoming an aging society,the incidence of diabetes and diabetic foot have been increasing.Diabetic foot has become one of the main health-related killers due to its high disability and mortality rates.Negative pressure wound therapy(NPWT)is one of the most effective techniques for the treatment of diabetic foot wounds and great progress,both in terms of research and its clinical application,has been made in the last 20 years of its development.However,due to the complex pathogenesis and management of diabetic foot,irregular application of NPWT often leads to complications,such as infection,bleeding and necrosis,that seriously affect its treatment outcomes.In 2020,under the leadership of Burns,Trauma and Tissue Repair Committee of the Cross-Straits Medicine Exchange Association,the writing group for‘Consensus on the application of negative pressure wound therapy of diabetic foot wounds’was established with the participation of scholars from the specialized areas of burns,endocrinology,vascular surgery,orthopedics and wound repair.Drawing on evidence-based practice suggested by the latest clinical research,this consensus proposes the best clinical practice guidelines for the application and prognostic evaluation of NPWT for diabetic foot.The consensus aims to support the formation of standardized treatment schemes that clinicians can refer to when treating cases of diabetic foot.展开更多
Effects of maize (Zea mays L.) volatiles induced by larvae of the Asian corn borer, Ostriniafurnacalis (Guenee), on the orientation behaviors of Asian corn borer larvae and oviposition of the females were investig...Effects of maize (Zea mays L.) volatiles induced by larvae of the Asian corn borer, Ostriniafurnacalis (Guenee), on the orientation behaviors of Asian corn borer larvae and oviposition of the females were investigated. Nineteen volatile chemicals, with terpenes being the major components, were identified from maize plants attacked by third instar Asian corn borer larvae. Coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses revealed some electroantennographic differences between female and male Asian corn borer antennae in response to larvae-induced maize volatiles; female responded to (E)-2-hexenal, nonanal, (Z)-3-hexen-l-ol and three unknown compounds while the male only responded to (E)-2-hexenal, nonanal and one unknown compound. In laboratory orientation bioassays, Asian corn borer neonate larvae were attracted to extracts collected from Asian corn borer-damaged plants as well as to synthetic farnesene, but were repelled by (Z)-3-hexen- 1 -ol. In laboratory oviposition bioassays, gravid females laid fewer eggs on plants damaged by larvae than on mechanically damaged plants or undamaged plants. Adult Asian corn borer females deposited fewer eggs on wax paper treated with (E)-2-hexenal or (Z)-3-hexen-l-ol than on wax paper treated with hexane (control). The results suggest that Asian corn borer can affect the behaviors of conspecific larvae and adults by changing host plant volatiles.展开更多
A study was carried out on the effects of processing and composition on the structure and properties of P/M EP741NP type alloys. The objectives of this study were to understand the role of Hf in a P/M superalloy conta...A study was carried out on the effects of processing and composition on the structure and properties of P/M EP741NP type alloys. The objectives of this study were to understand the role of Hf in a P/M superalloy containing high niobium used in aircraft engines and to determine the effects of extrusion and forging the powders as contrasted to HIPing (hot isostatic pressing) only. Two alloys of the P/M EP741NP composition were atomized: one alloy contained 0.26%Hfand the other was Hf free. After the as-atomized powders from both alloys were characterized, the powders were extruded into billets, forged and heat treated. After each process, the microstructures were characterized by SEM and the phases were extracted and identified by X-ray diffraction. The presence of Hf in the residues was probed by EDS (energy dispersive spectroscopy). The alloys were given the published Russian heat treatment as well as a more conventional heat treatment more typical of western powder alloys. Tensile, creep and stress rupture mechanical property tests were run. Results of the structural behavior of the alloys after each processing step will be presented and discussed. The role of the Hfon the mechanical properties will be discussed.展开更多
Recent advances in additive manufacturing enable redesigning material morphology on nano-,micro-,and meso-scale,for achieving an enhanced functionality on the macro-scale.From non-planar and flexible electronic circui...Recent advances in additive manufacturing enable redesigning material morphology on nano-,micro-,and meso-scale,for achieving an enhanced functionality on the macro-scale.From non-planar and flexible electronic circuits,through biomechanically realistic surgical models,to shoe soles individualized for the user comfort,multiple scientific and technological areas undergo material-property redesign and enhancement enabled by 3D printing.Fiber-device technology is currently entering such a transformation.In this paper,we review the recent advances in adopting 3D printing for direct digital manufacturing of fiber preforms with complex cross-sectional architectures designed for the desired thermally drawn fiber-device functionality.Subsequently,taking a recursive manufacturing approach,such fibers can serve as a raw material for 3D printing,resulting in macroscopic objects with enhanced functionalities,from optoelectronic to bio-functional,imparted by the fiber-devices properties.展开更多
We applied a Monte Carlo method -- simulated annealing algorithm -- to carry out the design of multilayer achromatic waveplate. We present solutions for three-, six- and ten-layer achromatic waveplates. The optimized ...We applied a Monte Carlo method -- simulated annealing algorithm -- to carry out the design of multilayer achromatic waveplate. We present solutions for three-, six- and ten-layer achromatic waveplates. The optimized retardance settings are found to be 89°51′39″ ± 0°33′37″ and 89°54′46″ ± 0°22′4″ for the six- and ten-layer waveplates, respectively, for a wavelength range from 1000 nm to 1800 nm. The polarimetric properties of multilayer waveplates are investigated based on several numerical experiments. In contrast to previously proposed three-layer achromatic waveplate, the fast axes of the new six- and ten-layer achromatic waveplate remain at fixed angles, independent of the wavelength. Two applications of multilayer achromatic waveplate are discussed, the general-purpose phase shifter and the birefringent filter in the Infrared Imaging Magnetograph (IRIM) system of the Big Bear Solar Observatory (BBSO). We also checked an experimental method to measure the retardance of waveplates.展开更多
Magnetic topology has been a key to the understanding of magnetic energy release mechanism. Based on observed vector magnetograms, we have determined the threedimensional (3D) topology skeleton of the magnetic field...Magnetic topology has been a key to the understanding of magnetic energy release mechanism. Based on observed vector magnetograms, we have determined the threedimensional (3D) topology skeleton of the magnetic fields in the active region NOAA 10720. The skeleton consists of six 3D magnetic nulls and a network of corresponding spines, fans, and null-null lines. For the first time, we have identified a spiral magnetic null in Sun's corona. The magnetic lines of force twisted around the spine of the null, forming a 'magnetic wreath' with excess of free magnetic energy and resembling observed brightening structures at extraultraviolet (EUV) wavebands. We found clear evidence of topology eruptions which are referred to as catastrophic changes of topology skeleton associated with a coronal mass ejection (CME) and an explosive X-ray flare. These results shed new lights on the structural complexity and its role in explosive magnetic activity. The concept of flux rope has been widely used in modelling explosive magnetic activity, although their observational identity is rather obscure or, at least, lacking of necessary details up to date. We suggest that the magnetic wreath associated with the 3D spiral null is likely an important class of the physical entity of flux ropes.展开更多
A fluid flow model consisting of Bernoulli’s law in its normal form, the equation of state of air, and the cross-stream force balance between a downward pressure gradient and the upward centrifugal force on fluid par...A fluid flow model consisting of Bernoulli’s law in its normal form, the equation of state of air, and the cross-stream force balance between a downward pressure gradient and the upward centrifugal force on fluid particles moving along curved streamlines over the top circular wing surface involving three equations in three unknowns (pressure, density and velocity) are solved to show that both density and pressure decrease upward as the inverse square of the distance from the circle’s center, and the velocity is independent of that dis-tance. These derived characteristics are used to explain the lift force on the wing in what is believed to be a novel way.展开更多
Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-260℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the grains.The ...Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-260℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the grains.The results indicated that the average grain sizes were refined forming gradient structure with increasing specimen radial position from center(12.2-5.4μm),and that the initial basal texture intensity of the extruded magnesium alloy was weakened from 46.2 to 8.3.Furthermore,the extension twins(ETs)could be disintegrated from the twins forming separated twins with smaller sizes.Interestingly,ETs with the same twin variant intersecting with each other could be coalesced forming grains with similar orientation,while ETs with different twin variants were separated by twins boundaries contributing to grain refinement.Moreover,in addition to the conventional continuous dynamic recrystallized(CDRX)grains with 30˚orientation rotated around C-axis of the parent grains,CDRXed grains with 30˚rotation around a-axis and random rotation axis were also discerned.Besides,the CDRX evolution induced twins were also elaborated,exhibiting the complex competition between CDRX and twining.Hot torsion deformation with constant decreasing temperatures rate is an effective way of grain refinement and texture modification.展开更多
The well-known question,why do people keep doing the same thing but expect a different result,applies to nursing education.Healthcare delivery systems are in constant evolution yet much of nursing education operates w...The well-known question,why do people keep doing the same thing but expect a different result,applies to nursing education.Healthcare delivery systems are in constant evolution yet much of nursing education operates with traditional teaching approaches expecting to produce graduates suitable for rapidly changing healthcare delivery systems.Nursing is a practice-based discipline with its own body of knowledge situated within the context of dy-namic nursing practice.It is the responsibility of nursing academia to prepare graduates suitable for practice.If we are to change prac-tice,we must rethink education.The impact and interruptions of the global COVID-19 pandemic gave rise to questions on best prac-tices to guide nursing education into the future.展开更多
The extruded AZ80+0.4%Ce magnesium alloy was twisted in the temperature range of 300-380℃by using a Gleeble 3500 thermal simulation test machine with a torsion unit.The deformed cylindrical specimens were cooled at a...The extruded AZ80+0.4%Ce magnesium alloy was twisted in the temperature range of 300-380℃by using a Gleeble 3500 thermal simulation test machine with a torsion unit.The deformed cylindrical specimens were cooled at a cooling rate of 10℃/s or 0.1℃/s,respectively,and aged at 170℃.The microstructure analysis results showed that the grain size decreased with increasing specimen radial position from center(SRPC),and that the strong initial basal texture of the extruded magnesium alloy was weakened.Both continuous and discontinuous dynamic recrystallization mechanisms were involved in contributing to the grain refinement for all specimens investigated.And a novel extension twinning induced dynamic recrystallization mechanism was proposed for specimen deformed at 300℃.For the specimens deformed at 300℃and 340℃followed by a slow cooling rate(0.1℃/s),precipitates of various shapes(β-Mg_(17)Al_(12)),with the dominant precipitates being on the grains boundaries,appeared on the surface section.For specimen deformed at 380℃,lamellar precipitates(LPS)in the interiors of the grains were predominant.After aging,the LPS still dominated for specimens twisted at 380℃;however,the LPS gradually decreased with decreasing deformation temperatures from 380℃to 300℃.Dynamically precipitatedβ,especially those decorating the grain boundaries,changed the competition pictures for the LPS and precipitates of other shapes after aging.Interestingly,LPS dominated the areas for the center section of the specimens after aging regardless of deformation temperatures.Low temperature deformation with high SRPC followed by rapid cooling rate increased the micro hardness of the alloy after aging due to refined grain,reduced precipitates size,decreased lamellar spacing as well as strain hardening.展开更多
Objective:To investigate the genetic correlations between epithelial growth factor receptor(EGFR)mutation and FHIT methylation in patients diagnosed with lung adenocarcinoma(AC)and pulmonary tuberculosis(TB).Methods:T...Objective:To investigate the genetic correlations between epithelial growth factor receptor(EGFR)mutation and FHIT methylation in patients diagnosed with lung adenocarcinoma(AC)and pulmonary tuberculosis(TB).Methods:The presence of EGFR mutations and the methylation status of the FHIT gene in patients presenting with AC and TB were analyzed.The correlation between TB status and the observed genetic and epigenetic variations was also examined.Results:Among the 90 patients included in the study,38 exhibited EGFR mutations(14 among those with TB and 24 among those without TB),while 29 exhibited FHIT myelination(19 among those with TB and 10 among those without TB).Furthermore,the protein expression levels of EGFR and FHIT were significantly higher in patients diagnosed solely with AC compared to those presenting with both AC and TB.A robust inverse correlation was identified between TB status and the frequency of EGFR mutation(P<0.001).Moreover,significant associations were observed between TB status and FHIT methylation(P<0.01).Conclusion:The findings suggest a correlation between TB and the prevalence of EGFR mutation and FHIT methylation in the pathogenesis of AC.展开更多
Lycopene is a naturally occurring red carotenoid compound that is found in watermelon.Lycopene has antioxidant properties.Lycopene content,sugar content and hollowheart resistance are subject to significant genotype...Lycopene is a naturally occurring red carotenoid compound that is found in watermelon.Lycopene has antioxidant properties.Lycopene content,sugar content and hollowheart resistance are subject to significant genotype×environment interaction(G×E),which makes breeding for these fruit quality traits difficult.The objectives of this study were to(i)evaluate the influence of years and locations on lycopene content,sugar content and hollowheart resistance for a set of watermelon genotypes,and(ii)identify genotypes with high stability for lycopene,sugar,and hollowheart resistance.A diverse set of 40 genotypes was tested over 3 years and 8 locations across the southern United States in replicated,multi-harvest trials.Lycopene was tested in a subset of 10 genotypes.Data were analyzed using univariate and multivariate stability statistics(BLUP-GGE biplot)using SASGxE and RGxE programs.There were strong effects of environment as well as G×E interaction on watermelon quality traits.On the basis of stability measures,genotypes were classified as stable or unstable for each quality trait.'Crimson Sweet'is an inbred line with high quality trait performance as well as trait stability.'Stone Mountain','Tom Watson','Crimson Sweet'and'Minilee'were among the best genotypes for lycopene content,sugar content and hollowheart resistance.We developed a stability chart based on marketable yield and average ranking generated from different stability measures for yield attributes and quality traits.The chart will assist in choosing parents for improvement of watermelon cultivars.See http://cuke.hort.ncsu.edu/cucurbit/wmelon/wmelonmain.html.展开更多
At present, the social security problems of the disabled in most rural areas are more prominent. There is a big gap between their social security needs and the system and policies. It is an important task for the rura...At present, the social security problems of the disabled in most rural areas are more prominent. There is a big gap between their social security needs and the system and policies. It is an important task for the rural disabled to help the disabled to get rid of poverty and to solve their food and clothing. It is an important task to build a new socialist countryside and build a well-offsociety in an all-round way. It needs to be more effectively solved in the system construction of social security and social services. This paper, taking the rural of Shuyang County of Jiangsu Province as the research object, analyzes the situation and demand of the social security of the disabled in China, points out its existing problems and outs forward some countermeasures and suggestions.展开更多
Linear governing equations are formulated for the depth decay of the pressure and velocity variations associated with propagating surface gravity waves. These governing equations come from combining Bernoulli’s equat...Linear governing equations are formulated for the depth decay of the pressure and velocity variations associated with propagating surface gravity waves. These governing equations come from combining Bernoulli’s equation for steady frictionless flow along a streamline and the crossstream force balance involving gravity, the centrifugal force and a pressure gradient. Qualitative solutions show that the pressure decreases downward faster than the velocity does and at a rate that is probably not the normal exponential decrease, which does not agree with the classical result. The radius of curvature of the streamlines is a non-constant coefficient in these equations and it needs to be supplied, either from measurements or another theory, in order to complete the solution of the derived governing equations. There is no sensitivity of the solution to the exact path the radius of curvature takes between its minimum value at the surface of a crest and trough and infinity at great depth. In the future measurements, perhaps streak photographs, will be needed to distinguish between the new and old theories.展开更多
A physical explanation is given for the observations that ocean surface gravity waves can travel up to half way around the world from generation in a wind storm to dissipation on shore. Inherent in these waves is an o...A physical explanation is given for the observations that ocean surface gravity waves can travel up to half way around the world from generation in a wind storm to dissipation on shore. Inherent in these waves is an orbital fluid particle motion, known from laboratory experiments, that has no friction according to the Navier-Stokes equations. The prediction is based on application of Bernoulli’s law to all the closed orbital paths of the fluid particles and the cross-stream force balance on the particles between a pressure gradient and the centrifugal force in each orbital loop.展开更多
When a solid cone with smooth side and base rotates about its long axis in a still fluid, theory says that the cone will advance along the direction of the axis, base first and apex last. Bernoulli’s law for closed s...When a solid cone with smooth side and base rotates about its long axis in a still fluid, theory says that the cone will advance along the direction of the axis, base first and apex last. Bernoulli’s law for closed streamline loops is combined with the cross-stream force balance between the centrifugal force and a pressure gradient in order to obtain the result, which is believed to be new. Confirmation of the prediction awaits observational evidence.展开更多
Solar flare prediction plays an important role in understanding and forecasting space weather.The main goal of the Helioseismic and Magnetic Imager(HMI), one of the instruments on NASA's Solar Dynamics Observatory...Solar flare prediction plays an important role in understanding and forecasting space weather.The main goal of the Helioseismic and Magnetic Imager(HMI), one of the instruments on NASA's Solar Dynamics Observatory, is to study the origin of solar variability and characterize the Sun's magnetic activity.HMI provides continuous full-disk observations of the solar vector magnetic field with high cadence data that lead to reliable predictive capability;yet, solar flare prediction effort utilizing these data is still limited. In this paper, we present a machine-learning-as-a-service(MLaa S) framework, called Deep Sun,for predicting solar flares on the web based on HMI's data products. Specifically, we construct training data by utilizing the physical parameters provided by the Space-weather HMI Active Region Patch(SHARP)and categorize solar flares into four classes, namely B, C, M and X, according to the X-ray flare catalogs available at the National Centers for Environmental Information(NCEI). Thus, the solar flare prediction problem at hand is essentially a multi-class(i.e., four-class) classification problem. The Deep Sun system employs several machine learning algorithms to tackle this multi-class prediction problem and provides an application programming interface(API) for remote programming users. To our knowledge, Deep Sun is the first MLaa S tool capable of predicting solar flares through the internet.展开更多
We investigated metal-organic vapor phase epitaxy grown(InGa)(AsSb)/GaAs/GaP Stranski–Krastanov quantum dots(QDs)with potential applications in QD-Flash memories by cross-sectional scanning tunneling microscopy(X-STM...We investigated metal-organic vapor phase epitaxy grown(InGa)(AsSb)/GaAs/GaP Stranski–Krastanov quantum dots(QDs)with potential applications in QD-Flash memories by cross-sectional scanning tunneling microscopy(X-STM)and atom probe tomography(APT).The combination of X-STM and APT is a very powerful approach to study semiconductor heterostructures with atomic resolution,which provides detailed structural and compositional information on the system.The rather small QDs are found to be of truncated pyramid shape with a very small top facet and occur in our sample with a very high density of∼4×10^(11) cm^(−2).APT experiments revealed that the QDs are GaAs rich with smaller amounts of In and Sb.Finite element(FE)simulations are performed using structural data from X-STM to calculate the lattice constant and the outward relaxation of the cleaved surface.The composition of the QDs is estimated by combining the results from X-STM and the FE simulations,yielding∼In_(x)Ga_(1−x)As_(1−y)Sb_(y),where x=0.25–0.30 and y=0.10–0.15.Noticeably,the reported composition is in good agreement with the experimental results obtained by APT,previous optical,electrical,and theoretical analysis carried out on this material system.This confirms that the InGaSb and GaAs layers involved in the QD formation have strongly intermixed.A detailed analysis of the QD capping layer shows the segregation of Sb and In from the QD layer,where both APT and X-STM show that the Sb mainly resides outside the QDs proving that Sb has mainly acted as a surfactant during the dot formation.Our structural and compositional analysis provides a valuable insight into this novel QD system and a path for further growth optimization to improve the storage time of the QD-Flash memory devices.展开更多
An example of sea level pressure (SLP) and sea surface temperature (SST) is displayed for a summer month based on historical monthly mean data for the North Pacific. A double North Pacific High (NPH) co-occurred with ...An example of sea level pressure (SLP) and sea surface temperature (SST) is displayed for a summer month based on historical monthly mean data for the North Pacific. A double North Pacific High (NPH) co-occurred with a double large-scale SST maximum along 40 N. Centers of the two NPHs had very nearly the same longitudes as did the SST maxima. Seven similar coincidences happened within the 30-year records. These particular associations between extrema of SLPs and SSTs enhance a previously published conjecture that single and double NPHs are caused by heat transfer from the sea surface to the atmosphere. The eastern SST maximum is the signature of a permanent wide warm surface current flowing northeast off California. To the west of it in the summer is a transient wide warm surge of surface water flowing north as it crosses mid-latitudes. These are the heat sources that generate the single and double NPHs.展开更多
文摘The association between inflammatory bowel disease(IBD) and colorectal cancer(CRC) has been recognised since 1925 and still accounts for 10%-15% of deaths in IBD.IBD-associated CRC(IBD-CRC) affects patients at a younger age than sporadic CRC.The prognosis for sporadic CRC and IBD-CRC is similar,with a 5-year survival of approximately 50%.Identifying at risk patients and implementing appropriate surveillance for these patients is central to managing the CRC risk in IBD.The increased risk of colorectal cancer in association with IBD is thought to be due to genetic and acquired factors.The link between inflammation and cancer is well recognised but the molecular biology,immune pathobiology and genetics of IBD-CRC are areas of much ongoing research.This review examines the literature relating to IBD-CRC,focusing on the incidence of IBD-CRC and examining potential risk factors including age at diagnosis,gender,duration and extent of colitis,severity of inflammation,family history of sporadic CRC and co-existent primary sclerosing cholangitis(PSC).Confirmed risk factors for IBD-CRC are duration,severity and extent of colitis,the presence of co-existent PSC and a family history of CRC.There is insufficient evidence currently to support an increased frequency of surveillance for patients diagnosed with IBD at a younger age.Evidence-based guidelines advise surveillance colonoscopy for patients with colitis 8 to 10 years after diagnosis,with the interval for further surveillance guided by risk factors(extent of disease,family history of CRC,post-inflammatory polyps,concomitant PSC,personal history of colonic dysplasia,colonic strictures).There is a move away from using random colonic biopsies towards targeted biopsies aimed at abnormal areas identified by newer colonoscopic techniques(narrow band imaging,chromoendoscopy,confocal microendoscopy).
基金Research on in situ skin repair and regeneration based on micro-tissue engineering technology and 3D printing.(The National Key R&D Program of China,Grant Number 2019YFA0110503).The study on natural living micro-amniotic scaffolds to dynamic regulate immune inflammation and reconstruct wound repairing.(National Natural Science Foundation of China,Grant Number 81971836).The systemic study of miR-23b_24-1 cluster in the prevention and treatment of MODS caused by sepsis after burns.(National Natural Science Foundation of China,Grant Number 81930057).The experimental study on regulating the immune inflammatory microenvironment of burn wounds and promoting repair and regeneration based on micro-tissue engineering technology.(National Natural Science Foundation of China,Grant Number 81871559).
文摘Because China is becoming an aging society,the incidence of diabetes and diabetic foot have been increasing.Diabetic foot has become one of the main health-related killers due to its high disability and mortality rates.Negative pressure wound therapy(NPWT)is one of the most effective techniques for the treatment of diabetic foot wounds and great progress,both in terms of research and its clinical application,has been made in the last 20 years of its development.However,due to the complex pathogenesis and management of diabetic foot,irregular application of NPWT often leads to complications,such as infection,bleeding and necrosis,that seriously affect its treatment outcomes.In 2020,under the leadership of Burns,Trauma and Tissue Repair Committee of the Cross-Straits Medicine Exchange Association,the writing group for‘Consensus on the application of negative pressure wound therapy of diabetic foot wounds’was established with the participation of scholars from the specialized areas of burns,endocrinology,vascular surgery,orthopedics and wound repair.Drawing on evidence-based practice suggested by the latest clinical research,this consensus proposes the best clinical practice guidelines for the application and prognostic evaluation of NPWT for diabetic foot.The consensus aims to support the formation of standardized treatment schemes that clinicians can refer to when treating cases of diabetic foot.
文摘Effects of maize (Zea mays L.) volatiles induced by larvae of the Asian corn borer, Ostriniafurnacalis (Guenee), on the orientation behaviors of Asian corn borer larvae and oviposition of the females were investigated. Nineteen volatile chemicals, with terpenes being the major components, were identified from maize plants attacked by third instar Asian corn borer larvae. Coupled gas chromatographic-electroantennographic detection (GC-EAD) analyses revealed some electroantennographic differences between female and male Asian corn borer antennae in response to larvae-induced maize volatiles; female responded to (E)-2-hexenal, nonanal, (Z)-3-hexen-l-ol and three unknown compounds while the male only responded to (E)-2-hexenal, nonanal and one unknown compound. In laboratory orientation bioassays, Asian corn borer neonate larvae were attracted to extracts collected from Asian corn borer-damaged plants as well as to synthetic farnesene, but were repelled by (Z)-3-hexen- 1 -ol. In laboratory oviposition bioassays, gravid females laid fewer eggs on plants damaged by larvae than on mechanically damaged plants or undamaged plants. Adult Asian corn borer females deposited fewer eggs on wax paper treated with (E)-2-hexenal or (Z)-3-hexen-l-ol than on wax paper treated with hexane (control). The results suggest that Asian corn borer can affect the behaviors of conspecific larvae and adults by changing host plant volatiles.
文摘A study was carried out on the effects of processing and composition on the structure and properties of P/M EP741NP type alloys. The objectives of this study were to understand the role of Hf in a P/M superalloy containing high niobium used in aircraft engines and to determine the effects of extrusion and forging the powders as contrasted to HIPing (hot isostatic pressing) only. Two alloys of the P/M EP741NP composition were atomized: one alloy contained 0.26%Hfand the other was Hf free. After the as-atomized powders from both alloys were characterized, the powders were extruded into billets, forged and heat treated. After each process, the microstructures were characterized by SEM and the phases were extracted and identified by X-ray diffraction. The presence of Hf in the residues was probed by EDS (energy dispersive spectroscopy). The alloys were given the published Russian heat treatment as well as a more conventional heat treatment more typical of western powder alloys. Tensile, creep and stress rupture mechanical property tests were run. Results of the structural behavior of the alloys after each processing step will be presented and discussed. The role of the Hfon the mechanical properties will be discussed.
基金supported by IU Collaborative Research Grants(IUCRG)ProgramIU Faculty Research Support Program-External Resubmission(FRSP-ER)IU Emerging Areas of Research(EAR)Program.
文摘Recent advances in additive manufacturing enable redesigning material morphology on nano-,micro-,and meso-scale,for achieving an enhanced functionality on the macro-scale.From non-planar and flexible electronic circuits,through biomechanically realistic surgical models,to shoe soles individualized for the user comfort,multiple scientific and technological areas undergo material-property redesign and enhancement enabled by 3D printing.Fiber-device technology is currently entering such a transformation.In this paper,we review the recent advances in adopting 3D printing for direct digital manufacturing of fiber preforms with complex cross-sectional architectures designed for the desired thermally drawn fiber-device functionality.Subsequently,taking a recursive manufacturing approach,such fibers can serve as a raw material for 3D printing,resulting in macroscopic objects with enhanced functionalities,from optoelectronic to bio-functional,imparted by the fiber-devices properties.
文摘We applied a Monte Carlo method -- simulated annealing algorithm -- to carry out the design of multilayer achromatic waveplate. We present solutions for three-, six- and ten-layer achromatic waveplates. The optimized retardance settings are found to be 89°51′39″ ± 0°33′37″ and 89°54′46″ ± 0°22′4″ for the six- and ten-layer waveplates, respectively, for a wavelength range from 1000 nm to 1800 nm. The polarimetric properties of multilayer waveplates are investigated based on several numerical experiments. In contrast to previously proposed three-layer achromatic waveplate, the fast axes of the new six- and ten-layer achromatic waveplate remain at fixed angles, independent of the wavelength. Two applications of multilayer achromatic waveplate are discussed, the general-purpose phase shifter and the birefringent filter in the Infrared Imaging Magnetograph (IRIM) system of the Big Bear Solar Observatory (BBSO). We also checked an experimental method to measure the retardance of waveplates.
基金the National Natural Science Foundation of China
文摘Magnetic topology has been a key to the understanding of magnetic energy release mechanism. Based on observed vector magnetograms, we have determined the threedimensional (3D) topology skeleton of the magnetic fields in the active region NOAA 10720. The skeleton consists of six 3D magnetic nulls and a network of corresponding spines, fans, and null-null lines. For the first time, we have identified a spiral magnetic null in Sun's corona. The magnetic lines of force twisted around the spine of the null, forming a 'magnetic wreath' with excess of free magnetic energy and resembling observed brightening structures at extraultraviolet (EUV) wavebands. We found clear evidence of topology eruptions which are referred to as catastrophic changes of topology skeleton associated with a coronal mass ejection (CME) and an explosive X-ray flare. These results shed new lights on the structural complexity and its role in explosive magnetic activity. The concept of flux rope has been widely used in modelling explosive magnetic activity, although their observational identity is rather obscure or, at least, lacking of necessary details up to date. We suggest that the magnetic wreath associated with the 3D spiral null is likely an important class of the physical entity of flux ropes.
文摘A fluid flow model consisting of Bernoulli’s law in its normal form, the equation of state of air, and the cross-stream force balance between a downward pressure gradient and the upward centrifugal force on fluid particles moving along curved streamlines over the top circular wing surface involving three equations in three unknowns (pressure, density and velocity) are solved to show that both density and pressure decrease upward as the inverse square of the distance from the circle’s center, and the velocity is independent of that dis-tance. These derived characteristics are used to explain the lift force on the wing in what is believed to be a novel way.
基金supported by key technology research and development project of ShanXi province(20201102019)Natural science foundation of Shanxi Province(201901D111167)+2 种基金Shanxi Scholarship Council of China(2020-117)JCKY2018408B003Magnesium alloy high-performance XXX multi-directional extrusion technologyXX supporting scientific research project(xxxx-2019-021).
文摘Hot torsion tests for AZ80 magnesium alloy were carried out in the temperature range of 380℃-260℃,with a constant decreasing temperature rate of 10℃/s in order to weaken the basal texture and refine the grains.The results indicated that the average grain sizes were refined forming gradient structure with increasing specimen radial position from center(12.2-5.4μm),and that the initial basal texture intensity of the extruded magnesium alloy was weakened from 46.2 to 8.3.Furthermore,the extension twins(ETs)could be disintegrated from the twins forming separated twins with smaller sizes.Interestingly,ETs with the same twin variant intersecting with each other could be coalesced forming grains with similar orientation,while ETs with different twin variants were separated by twins boundaries contributing to grain refinement.Moreover,in addition to the conventional continuous dynamic recrystallized(CDRX)grains with 30˚orientation rotated around C-axis of the parent grains,CDRXed grains with 30˚rotation around a-axis and random rotation axis were also discerned.Besides,the CDRX evolution induced twins were also elaborated,exhibiting the complex competition between CDRX and twining.Hot torsion deformation with constant decreasing temperatures rate is an effective way of grain refinement and texture modification.
文摘The well-known question,why do people keep doing the same thing but expect a different result,applies to nursing education.Healthcare delivery systems are in constant evolution yet much of nursing education operates with traditional teaching approaches expecting to produce graduates suitable for rapidly changing healthcare delivery systems.Nursing is a practice-based discipline with its own body of knowledge situated within the context of dy-namic nursing practice.It is the responsibility of nursing academia to prepare graduates suitable for practice.If we are to change prac-tice,we must rethink education.The impact and interruptions of the global COVID-19 pandemic gave rise to questions on best prac-tices to guide nursing education into the future.
基金supported by key technology research and development project of Shan Xi province(20201102019)Natural science foundation of Shanxi Province(201901D111167)+1 种基金Shanxi Scholarship Council of China(2020–117)JCKY2018408B003Magnesium alloy high-performance XXX multi-directional extrusion technology and XX supporting scientific research project(xxxx-2019-021)。
文摘The extruded AZ80+0.4%Ce magnesium alloy was twisted in the temperature range of 300-380℃by using a Gleeble 3500 thermal simulation test machine with a torsion unit.The deformed cylindrical specimens were cooled at a cooling rate of 10℃/s or 0.1℃/s,respectively,and aged at 170℃.The microstructure analysis results showed that the grain size decreased with increasing specimen radial position from center(SRPC),and that the strong initial basal texture of the extruded magnesium alloy was weakened.Both continuous and discontinuous dynamic recrystallization mechanisms were involved in contributing to the grain refinement for all specimens investigated.And a novel extension twinning induced dynamic recrystallization mechanism was proposed for specimen deformed at 300℃.For the specimens deformed at 300℃and 340℃followed by a slow cooling rate(0.1℃/s),precipitates of various shapes(β-Mg_(17)Al_(12)),with the dominant precipitates being on the grains boundaries,appeared on the surface section.For specimen deformed at 380℃,lamellar precipitates(LPS)in the interiors of the grains were predominant.After aging,the LPS still dominated for specimens twisted at 380℃;however,the LPS gradually decreased with decreasing deformation temperatures from 380℃to 300℃.Dynamically precipitatedβ,especially those decorating the grain boundaries,changed the competition pictures for the LPS and precipitates of other shapes after aging.Interestingly,LPS dominated the areas for the center section of the specimens after aging regardless of deformation temperatures.Low temperature deformation with high SRPC followed by rapid cooling rate increased the micro hardness of the alloy after aging due to refined grain,reduced precipitates size,decreased lamellar spacing as well as strain hardening.
文摘Objective:To investigate the genetic correlations between epithelial growth factor receptor(EGFR)mutation and FHIT methylation in patients diagnosed with lung adenocarcinoma(AC)and pulmonary tuberculosis(TB).Methods:The presence of EGFR mutations and the methylation status of the FHIT gene in patients presenting with AC and TB were analyzed.The correlation between TB status and the observed genetic and epigenetic variations was also examined.Results:Among the 90 patients included in the study,38 exhibited EGFR mutations(14 among those with TB and 24 among those without TB),while 29 exhibited FHIT myelination(19 among those with TB and 10 among those without TB).Furthermore,the protein expression levels of EGFR and FHIT were significantly higher in patients diagnosed solely with AC compared to those presenting with both AC and TB.A robust inverse correlation was identified between TB status and the frequency of EGFR mutation(P<0.001).Moreover,significant associations were observed between TB status and FHIT methylation(P<0.01).Conclusion:The findings suggest a correlation between TB and the prevalence of EGFR mutation and FHIT methylation in the pathogenesis of AC.
文摘Lycopene is a naturally occurring red carotenoid compound that is found in watermelon.Lycopene has antioxidant properties.Lycopene content,sugar content and hollowheart resistance are subject to significant genotype×environment interaction(G×E),which makes breeding for these fruit quality traits difficult.The objectives of this study were to(i)evaluate the influence of years and locations on lycopene content,sugar content and hollowheart resistance for a set of watermelon genotypes,and(ii)identify genotypes with high stability for lycopene,sugar,and hollowheart resistance.A diverse set of 40 genotypes was tested over 3 years and 8 locations across the southern United States in replicated,multi-harvest trials.Lycopene was tested in a subset of 10 genotypes.Data were analyzed using univariate and multivariate stability statistics(BLUP-GGE biplot)using SASGxE and RGxE programs.There were strong effects of environment as well as G×E interaction on watermelon quality traits.On the basis of stability measures,genotypes were classified as stable or unstable for each quality trait.'Crimson Sweet'is an inbred line with high quality trait performance as well as trait stability.'Stone Mountain','Tom Watson','Crimson Sweet'and'Minilee'were among the best genotypes for lycopene content,sugar content and hollowheart resistance.We developed a stability chart based on marketable yield and average ranking generated from different stability measures for yield attributes and quality traits.The chart will assist in choosing parents for improvement of watermelon cultivars.See http://cuke.hort.ncsu.edu/cucurbit/wmelon/wmelonmain.html.
文摘At present, the social security problems of the disabled in most rural areas are more prominent. There is a big gap between their social security needs and the system and policies. It is an important task for the rural disabled to help the disabled to get rid of poverty and to solve their food and clothing. It is an important task to build a new socialist countryside and build a well-offsociety in an all-round way. It needs to be more effectively solved in the system construction of social security and social services. This paper, taking the rural of Shuyang County of Jiangsu Province as the research object, analyzes the situation and demand of the social security of the disabled in China, points out its existing problems and outs forward some countermeasures and suggestions.
文摘Linear governing equations are formulated for the depth decay of the pressure and velocity variations associated with propagating surface gravity waves. These governing equations come from combining Bernoulli’s equation for steady frictionless flow along a streamline and the crossstream force balance involving gravity, the centrifugal force and a pressure gradient. Qualitative solutions show that the pressure decreases downward faster than the velocity does and at a rate that is probably not the normal exponential decrease, which does not agree with the classical result. The radius of curvature of the streamlines is a non-constant coefficient in these equations and it needs to be supplied, either from measurements or another theory, in order to complete the solution of the derived governing equations. There is no sensitivity of the solution to the exact path the radius of curvature takes between its minimum value at the surface of a crest and trough and infinity at great depth. In the future measurements, perhaps streak photographs, will be needed to distinguish between the new and old theories.
文摘A physical explanation is given for the observations that ocean surface gravity waves can travel up to half way around the world from generation in a wind storm to dissipation on shore. Inherent in these waves is an orbital fluid particle motion, known from laboratory experiments, that has no friction according to the Navier-Stokes equations. The prediction is based on application of Bernoulli’s law to all the closed orbital paths of the fluid particles and the cross-stream force balance on the particles between a pressure gradient and the centrifugal force in each orbital loop.
文摘When a solid cone with smooth side and base rotates about its long axis in a still fluid, theory says that the cone will advance along the direction of the axis, base first and apex last. Bernoulli’s law for closed streamline loops is combined with the cross-stream force balance between the centrifugal force and a pressure gradient in order to obtain the result, which is believed to be new. Confirmation of the prediction awaits observational evidence.
基金supported by U.S.NSF grants AGS-1927578 and AGS-1954737the support of NASA under grants NNX16AF72G,80NSSC18K0673 and 80NSSC18K1705。
文摘Solar flare prediction plays an important role in understanding and forecasting space weather.The main goal of the Helioseismic and Magnetic Imager(HMI), one of the instruments on NASA's Solar Dynamics Observatory, is to study the origin of solar variability and characterize the Sun's magnetic activity.HMI provides continuous full-disk observations of the solar vector magnetic field with high cadence data that lead to reliable predictive capability;yet, solar flare prediction effort utilizing these data is still limited. In this paper, we present a machine-learning-as-a-service(MLaa S) framework, called Deep Sun,for predicting solar flares on the web based on HMI's data products. Specifically, we construct training data by utilizing the physical parameters provided by the Space-weather HMI Active Region Patch(SHARP)and categorize solar flares into four classes, namely B, C, M and X, according to the X-ray flare catalogs available at the National Centers for Environmental Information(NCEI). Thus, the solar flare prediction problem at hand is essentially a multi-class(i.e., four-class) classification problem. The Deep Sun system employs several machine learning algorithms to tackle this multi-class prediction problem and provides an application programming interface(API) for remote programming users. To our knowledge, Deep Sun is the first MLaa S tool capable of predicting solar flares through the internet.
文摘We investigated metal-organic vapor phase epitaxy grown(InGa)(AsSb)/GaAs/GaP Stranski–Krastanov quantum dots(QDs)with potential applications in QD-Flash memories by cross-sectional scanning tunneling microscopy(X-STM)and atom probe tomography(APT).The combination of X-STM and APT is a very powerful approach to study semiconductor heterostructures with atomic resolution,which provides detailed structural and compositional information on the system.The rather small QDs are found to be of truncated pyramid shape with a very small top facet and occur in our sample with a very high density of∼4×10^(11) cm^(−2).APT experiments revealed that the QDs are GaAs rich with smaller amounts of In and Sb.Finite element(FE)simulations are performed using structural data from X-STM to calculate the lattice constant and the outward relaxation of the cleaved surface.The composition of the QDs is estimated by combining the results from X-STM and the FE simulations,yielding∼In_(x)Ga_(1−x)As_(1−y)Sb_(y),where x=0.25–0.30 and y=0.10–0.15.Noticeably,the reported composition is in good agreement with the experimental results obtained by APT,previous optical,electrical,and theoretical analysis carried out on this material system.This confirms that the InGaSb and GaAs layers involved in the QD formation have strongly intermixed.A detailed analysis of the QD capping layer shows the segregation of Sb and In from the QD layer,where both APT and X-STM show that the Sb mainly resides outside the QDs proving that Sb has mainly acted as a surfactant during the dot formation.Our structural and compositional analysis provides a valuable insight into this novel QD system and a path for further growth optimization to improve the storage time of the QD-Flash memory devices.
文摘An example of sea level pressure (SLP) and sea surface temperature (SST) is displayed for a summer month based on historical monthly mean data for the North Pacific. A double North Pacific High (NPH) co-occurred with a double large-scale SST maximum along 40 N. Centers of the two NPHs had very nearly the same longitudes as did the SST maxima. Seven similar coincidences happened within the 30-year records. These particular associations between extrema of SLPs and SSTs enhance a previously published conjecture that single and double NPHs are caused by heat transfer from the sea surface to the atmosphere. The eastern SST maximum is the signature of a permanent wide warm surface current flowing northeast off California. To the west of it in the summer is a transient wide warm surge of surface water flowing north as it crosses mid-latitudes. These are the heat sources that generate the single and double NPHs.