Developing high efficient and stable red-emitting phosphors is very important in the areas of white lightingemitting diode(white-LED)and plant growth.Herein,series of Eu^(3+)-activated MF_(2)(M^(2+)=Ca^(2+),Sr^(2+),Ba...Developing high efficient and stable red-emitting phosphors is very important in the areas of white lightingemitting diode(white-LED)and plant growth.Herein,series of Eu^(3+)-activated MF_(2)(M^(2+)=Ca^(2+),Sr^(2+),Ba^(2+))red-emitting nanoparticles(NPs)were synthesized at room temperature.Excited at 394 nm,these resulting NPs can emit dazzling red emissions and their fluorescence intensities are sensitive to both dopant content and host compound.Moreover,it is found that the studied samples have admirable thermal stability,high quantum efficiencies and color purities,which can be regulated via changing host material.To assess the possible application of final products,three different white-LEDs were packaged by using Eu^(3+)-activated MF_(2)(M^(2+)=Ca^(2+),Sr^(2+),Ba^(2+))red-emitting NPs.Clearly,these manufactured white-LEDs can produce glaring warm white with satisfied electroluminescence behaviors,i.e.low correlated color temperature(<5000 K)and high color rendering index(>80).Furthermore,via using the designed NPs,three red-emitting LEDs were also fabricated so as to identify their applications in plant growth.Our findings imply that Eu^(3+)-activated MF_(2)(M^(2+)=Ca^(2+),Sr^(2+),Ba^(2+))NPs are well-suited for dual-functional lighting as red-emitting converters in the realms of white-LED and artificial plant growth LED.展开更多
Dynamical decoupling(DD)is normally ineffective when applied to DC measurement.In its straightforward implementation,DD nulls out DC signal as well while suppressing noise.This work proposes a phase relay method that ...Dynamical decoupling(DD)is normally ineffective when applied to DC measurement.In its straightforward implementation,DD nulls out DC signal as well while suppressing noise.This work proposes a phase relay method that is capable of continuously interrogating the DC signal over many DD cycles.We illustrate its efficacy when applied to the measurement of a weak DC magnetic field with an atomic spinor Bose-Einstein condensate.Sensitivities approaching standard quantum limit or Heisenberg limit are potentially realizable for a coherent spin state or a squeezed spin state of 10000 atoms,respectively,while ambient laboratory level noise is suppressed by DD.Our work offers a practical approach to mitigate the limitations of DD to DC measurement and would find other applications for resorting coherence in quantum sensing and quantum information processing research.展开更多
Wastewater-based epidemiology has emerged as a transformative surveillance tool for estimating substance consumption and monitoring disease prevalence,particularly during the COVID-19 pandemic.It enables the populatio...Wastewater-based epidemiology has emerged as a transformative surveillance tool for estimating substance consumption and monitoring disease prevalence,particularly during the COVID-19 pandemic.It enables the population-level monitoring of illicit drug use,pathogen prevalence,and environmental pollutant exposure.In this perspective,we summarize the key challenges specific to the Chinese context:(1)Sampling inconsistencies,necessitating standardized 24-hour composite protocols with high-frequency autosamplers(≤15 min/event)to improve the representativeness of samples.展开更多
Super-high strength NbTaTiZr high-entropy alloys(NbTaTiZr HEAs)have been successfully fabricated by the mechanical alloying(MA)with spark plasma sintering(SPS)technology,which is 2-fold compared with that of NbTaTiZr ...Super-high strength NbTaTiZr high-entropy alloys(NbTaTiZr HEAs)have been successfully fabricated by the mechanical alloying(MA)with spark plasma sintering(SPS)technology,which is 2-fold compared with that of NbTaTiZr HEAs prepared by vacuum arc melting(VAM).After the SPS process,the bulk NbTaTiZr alloy samples are provided with dual-phase body-centered cubic(BCC)structure and nanoscale grain size about 500 nm that is obviously smaller than that of NbTaTiZr HEA fabricated by VAM.When the sintering temperature is 800℃,the compressive fracture strength is the highest reaching at 2511±78 MPa.When the sintering temperature is 1000℃,the fracture strain is the highest reaching at 12.8%,and compressive fracture strength and yield strength also reach at 2274±91 MPa and 2172±47 MPa,respectively.The excellent mechanical properties of bulk NbTaTiZr alloy samples are attributed to the merits of MA and SPS,and the collaboration effect of ultra-fine grains strengthening,solid solution strengthening and interstitial solid solution strengthening.展开更多
Stress shielding is caused by the mismatch of stiffness between bone and implant materials,which may give rise to bone resorption and loosening,thereby causing implantation failure.There is a huge gap between Young’s...Stress shielding is caused by the mismatch of stiffness between bone and implant materials,which may give rise to bone resorption and loosening,thereby causing implantation failure.There is a huge gap between Young’s modulus of human bone and low Young’s modulusβTi alloys.A porous structure design can achieve the target of low Young’s modulus,and thus achieve the matching between human bone and implant materials.However,a suitable space holder(SH)that can be applied at high temperatures and sintering pressure has not been reported.In this study,the TiZrNbTa/Ti titanium matrix composite(TMC)with high strength and large ductility was used as scaffold materials and combined the SH technique with the spark plasma sintering(SPS)technique to obtain a porous structure.A novel space holder,i.e.,MgO particles was adopted,which can withstand high-temperature sintering accompanied by a sintering pressure.The porous TiZrNbTa/Ti with 40 vol.%MgO added exhibits a maximum strength of 345.9±10.4 MPa and Young’s modulus of 24.72±0.20 GPa,respectively.It possesses higher strength compared with human bone and matches Young’s modulus of human bone,which exhibits great potential for clinical application.展开更多
Senile plaque blue autofluorescence was discovered around 40 years ago,however,its impact on Alzheimer’s disease(AD)pathology has not been fully examined.We analyzed senile plaques with immunohistochemistry and fluor...Senile plaque blue autofluorescence was discovered around 40 years ago,however,its impact on Alzheimer’s disease(AD)pathology has not been fully examined.We analyzed senile plaques with immunohistochemistry and fluorescence imaging on AD brain sections and also Aβaggregation in vitro.In DAPI or Hoechst staining,the nuclear blue fluorescence could only be correctly assigned after subtracting the blue plaque autofluorescence.The flower-like structures wrapping dense-core blue fluorescence formed by cathepsin D staining could not be considered central-nucleated neurons with defective lysosomes since there was no nuclear staining in the plaque core when the blue autofluorescence was subtracted.Both Aβself-oligomers and Aβ/hemoglobin heterocomplexes generated blue autofluorescence.The Aβamyloid blue autofluorescence not only labels senile plaques but also illustrates red cell aggregation,hemolysis,cerebral amyloid angiopathy,vascular plaques,vascular adhesions,and microaneurysms.In summary,we conclude that Aβ-aggregation-generated blue autofluorescence is an excellent multi-amyloidosis marker in Alzheimer’s disease.展开更多
To understand the interface characteristics between the precipitateβ2'and the Mg matrix,and thus guide the development of new Mg-Zn alloys,we investigated the atomic interface structure,work of adhesion(Wad),and ...To understand the interface characteristics between the precipitateβ2'and the Mg matrix,and thus guide the development of new Mg-Zn alloys,we investigated the atomic interface structure,work of adhesion(Wad),and interfacial energy(γ)of Mg(0001)/β2’(MgZn_(2))(0001)interface,as well as the effect of segregation behavior of the introduced transition metal atoms(3d,4d and 5d)on interfacial bonding strength.The calculated works of adhesion and interfacial energies dementated that the Zn2-terminated MT+HCP configuration is the most stable structure for all considered models.Take the Zn2-MT+HCP interface as the research object,estimated segregated energies(Eseg)reveal that added transition metal atoms prefer to segregate at Mg-I and Mg-II sites.The predicted Wad and charge density difference results reveal that the segregation of alloying additives employed may all strengthen Mg(0001)/MgZn_(2)(0001)interface,with the enhancement effect of Os,Re,Tc,W,and Ru at the Mg-II site being the most pronounced.展开更多
Recently,human motion prediction has gained significant attention and achieved notable success.However,current methods primarily rely on training and testing with ideal datasets,overlooking the impact of variations in...Recently,human motion prediction has gained significant attention and achieved notable success.However,current methods primarily rely on training and testing with ideal datasets,overlooking the impact of variations in the viewing distance and viewing angle,which are commonly encountered in practical scenarios.In this study,we address the issue of model invariance by ensuring robust performance despite variations in view distances and angles.To achieve this,we employed Riemannian geometry methods to constrain the learning process of neural networks,enabling the prediction of invariances using a simple network.Furthermore,this enhances the application of motion prediction in various scenarios.Our framework uses Riemannian geometry to encode motion into a novel motion space to achieve prediction with an invariant viewing distance and angle using a simple network.Specifically,the specified path transport square-root velocity function is proposed to aid in removing the view-angle equivalence class and encode motion sequences into a flattened space.Motion coding by the geometry method linearizes the optimization problem in a non-flattened space and effectively extracts motion information,allowing the proposed method to achieve competitive performance using a simple network.Experimental results on Human 3.6M and CMU MoCap demonstrate that the proposed framework has competitive performance and invariance to the viewing distance and viewing angle.展开更多
<div style="text-align:justify;"> According to the problem that the low measurement accuracy of TH-1 satellite star sensor, the low frequency and “slow drift” error which cannot be ignored in the att...<div style="text-align:justify;"> According to the problem that the low measurement accuracy of TH-1 satellite star sensor, the low frequency and “slow drift” error which cannot be ignored in the attitude determination system, resulting in obvious random error in the horizontal position and elevation direction, and the change of the error with time and latitude, cannot be calibrated by the ground field of the real problem. In this paper, a low frequency detection model is established by using the principle of relative orientation, and the low frequency error is obtained by parallax elimination. Finally, the satellite attitude is compensated and the more accurate exterior orientation elements are obtained, thus improving the positioning accuracy and stability. The experimental results show that: the proposed methods are feasible, and by using the model to dynamically calibrate the exterior orientation angle elements on orbit, the plane and elevation errors of the ground points can be basically eliminated. The global uncontrollable positioning accuracy and stability of the photogrammetry satellite are improved. </div>展开更多
Hepatocellular carcinoma(HCC)is the most common primary liver cancer,accounting for about 90%of liver cancer cases.It is currently the fifth most common cancer in the world and the third leading cause of cancer-relate...Hepatocellular carcinoma(HCC)is the most common primary liver cancer,accounting for about 90%of liver cancer cases.It is currently the fifth most common cancer in the world and the third leading cause of cancer-related mortality.Moreover,recurrence of HCC is common.Microvascular invasion(MVI)is a major factor associated with recurrence in postoperative HCC.It is difficult to evaluate MVI using traditional imaging modalities.Currently,MVI is assessed primarily through pathological and immunohistochemical analyses of postoperative tissue samples.Needle biopsy is the primary method used to confirm MVI diagnosis before surgery.As the puncture specimens represent just a small part of the tumor,and given the heterogeneity of HCC,biopsy samples may yield false-negative results.Radiomics,an emerging,powerful,and non-invasive tool based on various imaging modalities,such as computed tomography,magnetic resonance imaging,ultrasound,and positron emission tomography,can predict the HCC-MVI status preoperatively by delineating the tumor and/or the regions at a certain distance from the surface of the tumor to extract the image features.Although positive results have been reported for radiomics,its drawbacks have limited its clinical translation.This article reviews the application of radiomics,based on various imaging modalities,in preoperative evaluation of HCC-MVI and explores future research directions that facilitate its clinical translation.展开更多
AIM: To compare the follow-up outcomes of ileosigmoidal anastomosis(ISA) and caecorectal anastomosis(CRA) in patients with slow transit constipation(STC) with or without melanosis coli(MC).METHODS: We collected the cl...AIM: To compare the follow-up outcomes of ileosigmoidal anastomosis(ISA) and caecorectal anastomosis(CRA) in patients with slow transit constipation(STC) with or without melanosis coli(MC).METHODS: We collected the clinical data of 48 STC patients with or without MC from May 2002 to May 2007.Twenty-six patients underwent CRA(14 with MC) and 22 cases received ISA(14 with MC).A 3-year postoperative follow-up was conducted.RESULTS: CRA improved the quality of life [evaluated by the gastrointestinal quality of life index(GIQLI)] in patients without MC,but was inferior to ISA in stool frequency and Wexner and GIQLI scores for MC patients.In the CRA group,patients with MC suffered worse outcomes than those without MC.CONCLUSION: CRA is more suitable for STC patients without MC; however,for STC patients with MC,ISA is a better choice.展开更多
PM2.5 separator directly affects the accuracy of PM2.5 sampling.The specification testing and evaluation for PM2.5 separator is particularly important,especially under China’s wide variation of terrain and climate.In...PM2.5 separator directly affects the accuracy of PM2.5 sampling.The specification testing and evaluation for PM2.5 separator is particularly important,especially under China’s wide variation of terrain and climate.In this study,first a static test apparatus based on polydisperse aerosol was established and calibrated to evaluate the performance of the PM2.5 separators.A uniform mixing chamber was developed to make particles mix completely.The aerosol concentration relative standard deviations of three test points at the same horizontal chamber position were less than 0.57%,and the particle size distribution obeyed logarithmic normal distribution with an R2 of 0.996.The flow rate deviation between the measurement and the set point flow rate agreed to within±1.0%in the range of-40 to 50℃.Secondly,the separation,flow and loading characteristics of three cyclone separators(VSCC-A,SCC-A and SCC112)were evaluated using this system.The results showed that the 50%cutoff sizes(D50)of the three cyclones were 2.48,2.47 and 2.44μm when worked at the manufacturer’s recommended flow rates,respectively.The geometric standard deviation(GSD)of the capture efficiency of VSCCA was 1.23,showed a slightly sharper than SCC-A(GSD=1.27),while the SCC112 did not meet the relevant indicator(GSD=1.2±0.1)with a GSD=1.44.The flow rate and loading test had a great effect on D50,while the GSD remained almost the same as before.In addition,the maintenance frequency under different air pollution conditions of the cyclones was summarized according to the loading test.展开更多
Prostate cancer(PCa)is one of the most common malignancies in Western countries.Studies have shown that androgen contributes to the progression of PCa,but how androgen promotes PCa remains largely unknown.Here,we demo...Prostate cancer(PCa)is one of the most common malignancies in Western countries.Studies have shown that androgen contributes to the progression of PCa,but how androgen promotes PCa remains largely unknown.Here,we demonstrated that androgen suppressed the expression of miR-760 depending on the interaction between androgen and androgen receptor(AR).miR-760 was downregulated in prostate cancer tissues compared with normal tissues.Functional experiments showed that miR-760 downregulation promoted the proliferation and growth of LNCaP and 22rv1 cells.In contrast,miR-760 ectopic expression inhibited the proliferation of LNCaP and 22 rv1 cells.DNA synthesis was suppressed by miR-760.Mechanistically,miR-760 bound to the 3 fUTR of interleukin 6(IL6).A mutation in the binding site disrupted their interaction.In addition,silencing of IL6 suppressed the proliferation of LNCaP and 22 rv1 cells.IL6 was upregulated in PCa tissues.Our study reveals that androgen downregulates miR-760 to promote the growth of PCa cells by regulating IL6.展开更多
BACKGROUND Hemodialysis is an advanced blood purification technique to manage kidney failure.However,for conventional hemodialysis,the high prevalence of dyslipidemia may cause cardiovascular diseases and an increase ...BACKGROUND Hemodialysis is an advanced blood purification technique to manage kidney failure.However,for conventional hemodialysis,the high prevalence of dyslipidemia may cause cardiovascular diseases and an increase in mortality.Moreover,toxins accumulating in the body over time may induce some complications.High flux hemodialysis can effectively improve disease indexes and clinical symptoms.AIM To investigate the efficacy of high flux hemodialysis in elderly patients with chronic kidney failure(CKF).METHODS A total of 66 elderly patients with CKF who were admitted to our hospital from October 2017 to October 2018 were included in the study.According to the therapies they received,the patients were divided into a study group and a control group with 33 patients in each group.The study group received high flux hemodialysis and the control group received conventional dialysis treatment.Kidney function,toxin levels in serum,and complications were compared in the two groups.RESULTS Before the treatment,there was no significant difference in kidney function,β2-microglobulin,or blood urea nitrogen between the two groups(P>0.05).In contrast,kidney function was better in the study group than in the control group after the treatment(P<0.05).In addition,the study group had significantly lower parathyroid hormone and serum cystatin C than the control group(P<0.05).The incidence of complications was 8.57%in the study group,which was lower than that of the control group(20.00%;P<0.05).CONCLUSION High flux hemodialysis may improve kidney function and reduce toxin levels in serum and the incidence of complications in elderly patients with CKF.展开更多
To alleviate ultrafiltration(UF) membrane fouling, the pre-coagulation of poly-aluminum chloride(PACl) with the aid of chitosan(CTS) was conducted for synthetic humic acid–kaolin water treatment. Pre-coagulation of t...To alleviate ultrafiltration(UF) membrane fouling, the pre-coagulation of poly-aluminum chloride(PACl) with the aid of chitosan(CTS) was conducted for synthetic humic acid–kaolin water treatment. Pre-coagulation of three molecular weights(MW) CTSs(50–190 kDa(CTSL), 190–310 kDa(CTSM) and 310–375 kDa(CTSH)) was optimized with slow-mixing speeds of 30, 60 and 90 r/min, respectively. The removal efficiency and floc properties as well as membrane fouling were analyzed, and were compared to results obtained by conventional coagulation with PACl. Results showed that variations in floc properties could be ascribed to the coagulation mechanisms of CTS_L/CTS_M/CTS_H at different slow-mixing speeds, resulting in reduced UF membrane fouling. Specifically, at the low speed of 30 r/min, all three CTS types produced flocs with similar properties, while CTSLresulted in the lowest removal efficiency and aggravated irreversible fouling. At the appropriate speed of 60 r/min, CTSMgenerated the most compact flocs with the combined effects of bridging and path mechanisms. The compact cake layer formed could alleviate irreversible fouling,which was beneficial for prolonging the operation of the UF membrane. At the high speed of90 r/min, CTSHformed fragile flocs and aggravated irreversible membrane fouling. We considered membrane fouling to be affected by floc properties and the resultant removal efficiency, which was governed by the MW of the CTS used and the slow-mixing speed applied as well.展开更多
Helium(He)is commercially produced from natural gas by low-temperature condensation.The process is energy extensive because of the extremely low He concentration(<0.3%)and the operation at cryogenic temperature.Her...Helium(He)is commercially produced from natural gas by low-temperature condensation.The process is energy extensive because of the extremely low He concentration(<0.3%)and the operation at cryogenic temperature.Herein we demonstrated DD3R zeolite membrane was efficient to extract He from natural gas at atmosphere temperature.The membrane performance was evaluated in terms of temperature,pressure and molar fractions.The overall membrane performance was dominated by the diffusivity selectivity.The single He permeance and ideal He/CH_(4) selectivity were 5.8×10^(-9)mol·m^(-2)·s^(-1)·Pa^(-1)and 79 under a feed pressure of 1.3 MPa.Even though He concentration was as low as 0.22%,the He permeance and He/CH_(4) mixture selectivity were 3.0×10^(-9)mol·m^(-2)·s^(-1)·Pa^(-1)and 44 at 0.7 MPa.During the longterm operation(~130 h)the membrane performance was stable even the feed mixture containing3.6%ethane as contaminations.The results approved the feasibility of DD3R zeolite membranes for He extraction from natural gas.展开更多
AIM： To establish if PTCHla transcriptional regulation region （TRR） is methylated in gastric cancer and its influence in gastric tumorigenesis.METHODS： The CpG islands in PTCHla TRR were analyzed by Methyl Primer ...AIM： To establish if PTCHla transcriptional regulation region （TRR） is methylated in gastric cancer and its influence in gastric tumorigenesis.METHODS： The CpG islands in PTCHla TRR were analyzed by Methyl Primer Express v1.0 software. The region from -643 to -355 bp （the transcription initiation site of PTCHla was designated as 0） that contained 19 CpG sites was chosen for bisulfitesequencing PCR （BSP） and methylation-specific PCR （MSP） detection. The gastric cancer cell line AGS was treated with 5-aza-2′-deoxycytidine （5-Aza-dC; 1 μmol/L） for 3 d. Alterations in PTCHla TRR methylation in treated AGS cells was measured through BSP clone sequences, and their PTCH1 expression was measured by quantitative RT-PCR. The cell cycle and apoptosis were observed with flow cytometry through propidium iodide （PI） staining or annexin V/PI double staining. The prevalence of PTCHla TRR methylation was investigated in 170 gastric cancer tissue samples and the adjacent normal tissues by MSP. The correlation of PTCH1a TRR methylation with PTCH1 expression or with patients＇ clinical features was analyzed.RESULTS： Methylation of PTCHla TRR was observed in AGS ceils and a subset of gastric cancer tissues （32%, 55/170）, while no methylation amplification products were observed in any normal tissues by MSP. The methylation of PTCH1α TRR was correlated negatively with PTCH1 expression （Spearman＇s r = -0.380, P = 0.000）. However, methylation of PTCHla TRR was not related to the gastric cancer patients＇ clinical features, such as sex, age of onset, clinical stage, lymph node metastasis or histological grade. The methylation of PTCHla TRR in AGS cells was almost converted to non-methylation after 5-Aza-dC treatment, which increased PTCH1 expression （5.3 ± 2.5 times; n = 3） and apoptosis rate （3.0 ± 0.26 times; P 〈 0.05; n = 3）.CONCLUSION： Methylation of PTCH1α TRR is present in a subset of gastric cancers and correlated negatively with PTCH1 expression. This may be an early event in gastric tumorigenesis and a new treatment target.展开更多
Trajectory clustering, potential source contribution function （PSCF） and concentration-weighted trajectory （CWT） methods were applied to investigate the transport pathways and identify potential sources of PM2.s a...Trajectory clustering, potential source contribution function （PSCF） and concentration-weighted trajectory （CWT） methods were applied to investigate the transport pathways and identify potential sources of PM2.s and PMIo in different seasons from June 2014 to May 2015 in Beijing. The cluster analyses showed that Beijing was affected by trajectories from the south and southeast in summer and autumn. In winter and spring, Beijing was not only affected by the trajectories from the south and southeast, but was also affected by trajectories from the north and northwest. In addition, the analyses of the pressure profile of backward trajectories showed that backward trajectories, which have important influence on Beijing, were mainly distributed above 970 hPa in summer and autumn and below 950 hPa in spring and winter. This indicates that PM2.s and PMIo were strongly affected by the near surface air masses in summer and autumn and by high altitude air masses in winter and spring. Results of PSCF and CV/T analyses showed that the largest potential source areas were identified in spring, followed by winter and autumn, then summer. In addition, potential source regions of PMIo were similar to those of PM2.5. There were a clear seasonal and spatial variation of the potential source areas of Beijing and the airflow in the horizontal and vertical directions. Therefore, more effective regional emission reduction measures in Beijing＇s surrounding provinces should be implemented to reduce emissions of regional sources in different seasons.展开更多
基金supported by Public Welfare Science and Technology Plan Project of Ningbo(No.2023S074)National Natural Science Foundation of China(No.12374087)One health Interdisciplinary Research Project in Ningbo University(No.HY202405).
文摘Developing high efficient and stable red-emitting phosphors is very important in the areas of white lightingemitting diode(white-LED)and plant growth.Herein,series of Eu^(3+)-activated MF_(2)(M^(2+)=Ca^(2+),Sr^(2+),Ba^(2+))red-emitting nanoparticles(NPs)were synthesized at room temperature.Excited at 394 nm,these resulting NPs can emit dazzling red emissions and their fluorescence intensities are sensitive to both dopant content and host compound.Moreover,it is found that the studied samples have admirable thermal stability,high quantum efficiencies and color purities,which can be regulated via changing host material.To assess the possible application of final products,three different white-LEDs were packaged by using Eu^(3+)-activated MF_(2)(M^(2+)=Ca^(2+),Sr^(2+),Ba^(2+))red-emitting NPs.Clearly,these manufactured white-LEDs can produce glaring warm white with satisfied electroluminescence behaviors,i.e.low correlated color temperature(<5000 K)and high color rendering index(>80).Furthermore,via using the designed NPs,three red-emitting LEDs were also fabricated so as to identify their applications in plant growth.Our findings imply that Eu^(3+)-activated MF_(2)(M^(2+)=Ca^(2+),Sr^(2+),Ba^(2+))NPs are well-suited for dual-functional lighting as red-emitting converters in the realms of white-LED and artificial plant growth LED.
基金Project supported by the NSAF(Grant No.U1930201)the National Natural Science Foundation of China(Grant Nos.12274331,91836101,and 91836302)+1 种基金the National Key R&D Program of China(Grant No.2018YFA0306504)Innovation Program for Quantum Science and Technology(Grant No.2021ZD0302100).
文摘Dynamical decoupling(DD)is normally ineffective when applied to DC measurement.In its straightforward implementation,DD nulls out DC signal as well while suppressing noise.This work proposes a phase relay method that is capable of continuously interrogating the DC signal over many DD cycles.We illustrate its efficacy when applied to the measurement of a weak DC magnetic field with an atomic spinor Bose-Einstein condensate.Sensitivities approaching standard quantum limit or Heisenberg limit are potentially realizable for a coherent spin state or a squeezed spin state of 10000 atoms,respectively,while ambient laboratory level noise is suppressed by DD.Our work offers a practical approach to mitigate the limitations of DD to DC measurement and would find other applications for resorting coherence in quantum sensing and quantum information processing research.
基金supported by the National Natural Science Foundation of China(Grant no.42307534)Discovery Project(DP220101790)+1 种基金The University of Queensland ScholarshipAustralian Research Council Discovery Project(DP220101790).
文摘Wastewater-based epidemiology has emerged as a transformative surveillance tool for estimating substance consumption and monitoring disease prevalence,particularly during the COVID-19 pandemic.It enables the population-level monitoring of illicit drug use,pathogen prevalence,and environmental pollutant exposure.In this perspective,we summarize the key challenges specific to the Chinese context:(1)Sampling inconsistencies,necessitating standardized 24-hour composite protocols with high-frequency autosamplers(≤15 min/event)to improve the representativeness of samples.
基金financially supported by the National Natural Science Foundation of China(No.51871077)Guangdong Basic and Applied Basic Research Foundation(No.2021A1515012626)+3 种基金Shenzhen Knowledge Innovation Plan-Fundamental Research(Discipline Distribution)(No.JCYJ20180507184623297)Shenzhen Science and Technology Plan-Technology Innovation(No.KQJSCX20180328165656256)Development and Reform Commission of Shenzhen Municipality-Shenzhen R&D Center for Al-based Hydrogen Hydrolysis Materials(No.ZX20190229)the Startup Foundation from Shenzhen and Startup Foundation from Harbin Institute of Technology(Shenzhen)。
文摘Super-high strength NbTaTiZr high-entropy alloys(NbTaTiZr HEAs)have been successfully fabricated by the mechanical alloying(MA)with spark plasma sintering(SPS)technology,which is 2-fold compared with that of NbTaTiZr HEAs prepared by vacuum arc melting(VAM).After the SPS process,the bulk NbTaTiZr alloy samples are provided with dual-phase body-centered cubic(BCC)structure and nanoscale grain size about 500 nm that is obviously smaller than that of NbTaTiZr HEA fabricated by VAM.When the sintering temperature is 800℃,the compressive fracture strength is the highest reaching at 2511±78 MPa.When the sintering temperature is 1000℃,the fracture strain is the highest reaching at 12.8%,and compressive fracture strength and yield strength also reach at 2274±91 MPa and 2172±47 MPa,respectively.The excellent mechanical properties of bulk NbTaTiZr alloy samples are attributed to the merits of MA and SPS,and the collaboration effect of ultra-fine grains strengthening,solid solution strengthening and interstitial solid solution strengthening.
基金financially supported by the National Natural Science Foundation of China(No.51871077)the Guangdong Basic and Applied Basic Research Foundation(No.2021A1515012626)+3 种基金the Shenzhen Knowledge Innovation Plan-Fundamental Re-search(Discipline Distribution)(No.JCYJ20180507184623297)the S henzhen Science and Technology Plan-Technology Innovation(No.KQJSCX20180328165656256)the Development and Reform Commission of Shenzhen Municipality-Shenzhen R&D Center for Al-based Hydrogen Hydrolysis Materials(No.ZX20190229)the Startup Foundation from Shenzhen and Startup Foundation from Harbin Institute of Technology(Shenzhen).
文摘Stress shielding is caused by the mismatch of stiffness between bone and implant materials,which may give rise to bone resorption and loosening,thereby causing implantation failure.There is a huge gap between Young’s modulus of human bone and low Young’s modulusβTi alloys.A porous structure design can achieve the target of low Young’s modulus,and thus achieve the matching between human bone and implant materials.However,a suitable space holder(SH)that can be applied at high temperatures and sintering pressure has not been reported.In this study,the TiZrNbTa/Ti titanium matrix composite(TMC)with high strength and large ductility was used as scaffold materials and combined the SH technique with the spark plasma sintering(SPS)technique to obtain a porous structure.A novel space holder,i.e.,MgO particles was adopted,which can withstand high-temperature sintering accompanied by a sintering pressure.The porous TiZrNbTa/Ti with 40 vol.%MgO added exhibits a maximum strength of 345.9±10.4 MPa and Young’s modulus of 24.72±0.20 GPa,respectively.It possesses higher strength compared with human bone and matches Young’s modulus of human bone,which exhibits great potential for clinical application.
基金supported by the National Natural Science Foundation of China(81472235)the Shanghai Jiao Tong University Medical and Engineering Project(YG2021QN53,YG2017MS71)+1 种基金the International Cooperation Project of National Natural Science Foundation of China(82020108017)the Innovation Group Project of National Natural Science Foundation of China(81921002).
文摘Senile plaque blue autofluorescence was discovered around 40 years ago,however,its impact on Alzheimer’s disease(AD)pathology has not been fully examined.We analyzed senile plaques with immunohistochemistry and fluorescence imaging on AD brain sections and also Aβaggregation in vitro.In DAPI or Hoechst staining,the nuclear blue fluorescence could only be correctly assigned after subtracting the blue plaque autofluorescence.The flower-like structures wrapping dense-core blue fluorescence formed by cathepsin D staining could not be considered central-nucleated neurons with defective lysosomes since there was no nuclear staining in the plaque core when the blue autofluorescence was subtracted.Both Aβself-oligomers and Aβ/hemoglobin heterocomplexes generated blue autofluorescence.The Aβamyloid blue autofluorescence not only labels senile plaques but also illustrates red cell aggregation,hemolysis,cerebral amyloid angiopathy,vascular plaques,vascular adhesions,and microaneurysms.In summary,we conclude that Aβ-aggregation-generated blue autofluorescence is an excellent multi-amyloidosis marker in Alzheimer’s disease.
基金supported by the Guangdong Major Project of Basic and Applied Basic Research(No.2020B0301030006)National Natural Science Foundation of China[Grant No.51871077]+2 种基金Shenzhen Knowledge Inno-vation Plan-Fundamental Research(Discipline Distribu-tion)[Grant No.JCYJ20180507184623297]Shenzhen Sci-ence and Technology Plan-Technology Innovation[Grant No.KQJSCX20180328165656256]Startup Foundation from Shenzhen and Startup Foundation from Harbin Institute of Technology(Shenzhen).
文摘To understand the interface characteristics between the precipitateβ2'and the Mg matrix,and thus guide the development of new Mg-Zn alloys,we investigated the atomic interface structure,work of adhesion(Wad),and interfacial energy(γ)of Mg(0001)/β2’(MgZn_(2))(0001)interface,as well as the effect of segregation behavior of the introduced transition metal atoms(3d,4d and 5d)on interfacial bonding strength.The calculated works of adhesion and interfacial energies dementated that the Zn2-terminated MT+HCP configuration is the most stable structure for all considered models.Take the Zn2-MT+HCP interface as the research object,estimated segregated energies(Eseg)reveal that added transition metal atoms prefer to segregate at Mg-I and Mg-II sites.The predicted Wad and charge density difference results reveal that the segregation of alloying additives employed may all strengthen Mg(0001)/MgZn_(2)(0001)interface,with the enhancement effect of Os,Re,Tc,W,and Ru at the Mg-II site being the most pronounced.
基金supported by the Beijing Municipal Science and Technology Commission and Zhongguancun Science Park Management Committee,No.Z221100002722020National Nature Science Foundation of China,No.62072045Innovation Transfer Fund of Peking University Third Hospital,No.BYSYZHKC2021110。
文摘Recently,human motion prediction has gained significant attention and achieved notable success.However,current methods primarily rely on training and testing with ideal datasets,overlooking the impact of variations in the viewing distance and viewing angle,which are commonly encountered in practical scenarios.In this study,we address the issue of model invariance by ensuring robust performance despite variations in view distances and angles.To achieve this,we employed Riemannian geometry methods to constrain the learning process of neural networks,enabling the prediction of invariances using a simple network.Furthermore,this enhances the application of motion prediction in various scenarios.Our framework uses Riemannian geometry to encode motion into a novel motion space to achieve prediction with an invariant viewing distance and angle using a simple network.Specifically,the specified path transport square-root velocity function is proposed to aid in removing the view-angle equivalence class and encode motion sequences into a flattened space.Motion coding by the geometry method linearizes the optimization problem in a non-flattened space and effectively extracts motion information,allowing the proposed method to achieve competitive performance using a simple network.Experimental results on Human 3.6M and CMU MoCap demonstrate that the proposed framework has competitive performance and invariance to the viewing distance and viewing angle.
文摘<div style="text-align:justify;"> According to the problem that the low measurement accuracy of TH-1 satellite star sensor, the low frequency and “slow drift” error which cannot be ignored in the attitude determination system, resulting in obvious random error in the horizontal position and elevation direction, and the change of the error with time and latitude, cannot be calibrated by the ground field of the real problem. In this paper, a low frequency detection model is established by using the principle of relative orientation, and the low frequency error is obtained by parallax elimination. Finally, the satellite attitude is compensated and the more accurate exterior orientation elements are obtained, thus improving the positioning accuracy and stability. The experimental results show that: the proposed methods are feasible, and by using the model to dynamically calibrate the exterior orientation angle elements on orbit, the plane and elevation errors of the ground points can be basically eliminated. The global uncontrollable positioning accuracy and stability of the photogrammetry satellite are improved. </div>
基金Supported by the Shanghai Municipal Commission of Science and Technology, No. 19411951200Clinical Research Plan of SHDC, No. SHDC2020CR3020Athe Research Startup Fund of Huashan Hospital Fudan University, No.2021QD035
文摘Hepatocellular carcinoma(HCC)is the most common primary liver cancer,accounting for about 90%of liver cancer cases.It is currently the fifth most common cancer in the world and the third leading cause of cancer-related mortality.Moreover,recurrence of HCC is common.Microvascular invasion(MVI)is a major factor associated with recurrence in postoperative HCC.It is difficult to evaluate MVI using traditional imaging modalities.Currently,MVI is assessed primarily through pathological and immunohistochemical analyses of postoperative tissue samples.Needle biopsy is the primary method used to confirm MVI diagnosis before surgery.As the puncture specimens represent just a small part of the tumor,and given the heterogeneity of HCC,biopsy samples may yield false-negative results.Radiomics,an emerging,powerful,and non-invasive tool based on various imaging modalities,such as computed tomography,magnetic resonance imaging,ultrasound,and positron emission tomography,can predict the HCC-MVI status preoperatively by delineating the tumor and/or the regions at a certain distance from the surface of the tumor to extract the image features.Although positive results have been reported for radiomics,its drawbacks have limited its clinical translation.This article reviews the application of radiomics,based on various imaging modalities,in preoperative evaluation of HCC-MVI and explores future research directions that facilitate its clinical translation.
文摘AIM: To compare the follow-up outcomes of ileosigmoidal anastomosis(ISA) and caecorectal anastomosis(CRA) in patients with slow transit constipation(STC) with or without melanosis coli(MC).METHODS: We collected the clinical data of 48 STC patients with or without MC from May 2002 to May 2007.Twenty-six patients underwent CRA(14 with MC) and 22 cases received ISA(14 with MC).A 3-year postoperative follow-up was conducted.RESULTS: CRA improved the quality of life [evaluated by the gastrointestinal quality of life index(GIQLI)] in patients without MC,but was inferior to ISA in stool frequency and Wexner and GIQLI scores for MC patients.In the CRA group,patients with MC suffered worse outcomes than those without MC.CONCLUSION: CRA is more suitable for STC patients without MC; however,for STC patients with MC,ISA is a better choice.
基金supported by the National Key Research and Development Program of China(Nos.2016YFF0103004 and 2017YFC0209504)the National Natural Science Foundation of China(No.91544218)+1 种基金the Science and Technological Fund of Anhui Province for Outstanding Youth(No.1808085J19)the Special Research of Public Welfare Industry of Environmental Protection(201409011)
文摘PM2.5 separator directly affects the accuracy of PM2.5 sampling.The specification testing and evaluation for PM2.5 separator is particularly important,especially under China’s wide variation of terrain and climate.In this study,first a static test apparatus based on polydisperse aerosol was established and calibrated to evaluate the performance of the PM2.5 separators.A uniform mixing chamber was developed to make particles mix completely.The aerosol concentration relative standard deviations of three test points at the same horizontal chamber position were less than 0.57%,and the particle size distribution obeyed logarithmic normal distribution with an R2 of 0.996.The flow rate deviation between the measurement and the set point flow rate agreed to within±1.0%in the range of-40 to 50℃.Secondly,the separation,flow and loading characteristics of three cyclone separators(VSCC-A,SCC-A and SCC112)were evaluated using this system.The results showed that the 50%cutoff sizes(D50)of the three cyclones were 2.48,2.47 and 2.44μm when worked at the manufacturer’s recommended flow rates,respectively.The geometric standard deviation(GSD)of the capture efficiency of VSCCA was 1.23,showed a slightly sharper than SCC-A(GSD=1.27),while the SCC112 did not meet the relevant indicator(GSD=1.2±0.1)with a GSD=1.44.The flow rate and loading test had a great effect on D50,while the GSD remained almost the same as before.In addition,the maintenance frequency under different air pollution conditions of the cyclones was summarized according to the loading test.
基金The research was financially supported by the Capital Special Scientific Projectsfor Health Development(2018-2-1025).
文摘Prostate cancer(PCa)is one of the most common malignancies in Western countries.Studies have shown that androgen contributes to the progression of PCa,but how androgen promotes PCa remains largely unknown.Here,we demonstrated that androgen suppressed the expression of miR-760 depending on the interaction between androgen and androgen receptor(AR).miR-760 was downregulated in prostate cancer tissues compared with normal tissues.Functional experiments showed that miR-760 downregulation promoted the proliferation and growth of LNCaP and 22rv1 cells.In contrast,miR-760 ectopic expression inhibited the proliferation of LNCaP and 22 rv1 cells.DNA synthesis was suppressed by miR-760.Mechanistically,miR-760 bound to the 3 fUTR of interleukin 6(IL6).A mutation in the binding site disrupted their interaction.In addition,silencing of IL6 suppressed the proliferation of LNCaP and 22 rv1 cells.IL6 was upregulated in PCa tissues.Our study reveals that androgen downregulates miR-760 to promote the growth of PCa cells by regulating IL6.
文摘BACKGROUND Hemodialysis is an advanced blood purification technique to manage kidney failure.However,for conventional hemodialysis,the high prevalence of dyslipidemia may cause cardiovascular diseases and an increase in mortality.Moreover,toxins accumulating in the body over time may induce some complications.High flux hemodialysis can effectively improve disease indexes and clinical symptoms.AIM To investigate the efficacy of high flux hemodialysis in elderly patients with chronic kidney failure(CKF).METHODS A total of 66 elderly patients with CKF who were admitted to our hospital from October 2017 to October 2018 were included in the study.According to the therapies they received,the patients were divided into a study group and a control group with 33 patients in each group.The study group received high flux hemodialysis and the control group received conventional dialysis treatment.Kidney function,toxin levels in serum,and complications were compared in the two groups.RESULTS Before the treatment,there was no significant difference in kidney function,β2-microglobulin,or blood urea nitrogen between the two groups(P>0.05).In contrast,kidney function was better in the study group than in the control group after the treatment(P<0.05).In addition,the study group had significantly lower parathyroid hormone and serum cystatin C than the control group(P<0.05).The incidence of complications was 8.57%in the study group,which was lower than that of the control group(20.00%;P<0.05).CONCLUSION High flux hemodialysis may improve kidney function and reduce toxin levels in serum and the incidence of complications in elderly patients with CKF.
基金supported by the National Natural Science Foundation of China(No.51478010)
文摘To alleviate ultrafiltration(UF) membrane fouling, the pre-coagulation of poly-aluminum chloride(PACl) with the aid of chitosan(CTS) was conducted for synthetic humic acid–kaolin water treatment. Pre-coagulation of three molecular weights(MW) CTSs(50–190 kDa(CTSL), 190–310 kDa(CTSM) and 310–375 kDa(CTSH)) was optimized with slow-mixing speeds of 30, 60 and 90 r/min, respectively. The removal efficiency and floc properties as well as membrane fouling were analyzed, and were compared to results obtained by conventional coagulation with PACl. Results showed that variations in floc properties could be ascribed to the coagulation mechanisms of CTS_L/CTS_M/CTS_H at different slow-mixing speeds, resulting in reduced UF membrane fouling. Specifically, at the low speed of 30 r/min, all three CTS types produced flocs with similar properties, while CTSLresulted in the lowest removal efficiency and aggravated irreversible fouling. At the appropriate speed of 60 r/min, CTSMgenerated the most compact flocs with the combined effects of bridging and path mechanisms. The compact cake layer formed could alleviate irreversible fouling,which was beneficial for prolonging the operation of the UF membrane. At the high speed of90 r/min, CTSHformed fragile flocs and aggravated irreversible membrane fouling. We considered membrane fouling to be affected by floc properties and the resultant removal efficiency, which was governed by the MW of the CTS used and the slow-mixing speed applied as well.
基金sponsored by the National Natural Science Foundation of China(21908097,22035002)the National Key Research and Development Program of China(2021YFC2101203)+1 种基金Jiangsu Specially-Appointed Professors Program and"333 Talent Project"of Jiangsu ProvinceState Key Laboratory of Materials-Oriented Chemical Engineering(ZK202002)。
文摘Helium(He)is commercially produced from natural gas by low-temperature condensation.The process is energy extensive because of the extremely low He concentration(<0.3%)and the operation at cryogenic temperature.Herein we demonstrated DD3R zeolite membrane was efficient to extract He from natural gas at atmosphere temperature.The membrane performance was evaluated in terms of temperature,pressure and molar fractions.The overall membrane performance was dominated by the diffusivity selectivity.The single He permeance and ideal He/CH_(4) selectivity were 5.8×10^(-9)mol·m^(-2)·s^(-1)·Pa^(-1)and 79 under a feed pressure of 1.3 MPa.Even though He concentration was as low as 0.22%,the He permeance and He/CH_(4) mixture selectivity were 3.0×10^(-9)mol·m^(-2)·s^(-1)·Pa^(-1)and 44 at 0.7 MPa.During the longterm operation(~130 h)the membrane performance was stable even the feed mixture containing3.6%ethane as contaminations.The results approved the feasibility of DD3R zeolite membranes for He extraction from natural gas.
基金Supported by City Hospital Trust Fund and the University of Birmingham Scientific Project Grant
文摘AIM： To establish if PTCHla transcriptional regulation region （TRR） is methylated in gastric cancer and its influence in gastric tumorigenesis.METHODS： The CpG islands in PTCHla TRR were analyzed by Methyl Primer Express v1.0 software. The region from -643 to -355 bp （the transcription initiation site of PTCHla was designated as 0） that contained 19 CpG sites was chosen for bisulfitesequencing PCR （BSP） and methylation-specific PCR （MSP） detection. The gastric cancer cell line AGS was treated with 5-aza-2′-deoxycytidine （5-Aza-dC; 1 μmol/L） for 3 d. Alterations in PTCHla TRR methylation in treated AGS cells was measured through BSP clone sequences, and their PTCH1 expression was measured by quantitative RT-PCR. The cell cycle and apoptosis were observed with flow cytometry through propidium iodide （PI） staining or annexin V/PI double staining. The prevalence of PTCHla TRR methylation was investigated in 170 gastric cancer tissue samples and the adjacent normal tissues by MSP. The correlation of PTCH1a TRR methylation with PTCH1 expression or with patients＇ clinical features was analyzed.RESULTS： Methylation of PTCHla TRR was observed in AGS ceils and a subset of gastric cancer tissues （32%, 55/170）, while no methylation amplification products were observed in any normal tissues by MSP. The methylation of PTCH1α TRR was correlated negatively with PTCH1 expression （Spearman＇s r = -0.380, P = 0.000）. However, methylation of PTCHla TRR was not related to the gastric cancer patients＇ clinical features, such as sex, age of onset, clinical stage, lymph node metastasis or histological grade. The methylation of PTCHla TRR in AGS cells was almost converted to non-methylation after 5-Aza-dC treatment, which increased PTCH1 expression （5.3 ± 2.5 times; n = 3） and apoptosis rate （3.0 ± 0.26 times; P 〈 0.05; n = 3）.CONCLUSION： Methylation of PTCH1α TRR is present in a subset of gastric cancers and correlated negatively with PTCH1 expression. This may be an early event in gastric tumorigenesis and a new treatment target.
基金supported by the National Key Foundation for Exploring Scientific Instrument(No.2012YQ060147)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB05040402)the Key Program of the Chinese 473 Academy of Sciences(No.KJZD-EW-TZ-G06-01)
文摘Trajectory clustering, potential source contribution function （PSCF） and concentration-weighted trajectory （CWT） methods were applied to investigate the transport pathways and identify potential sources of PM2.s and PMIo in different seasons from June 2014 to May 2015 in Beijing. The cluster analyses showed that Beijing was affected by trajectories from the south and southeast in summer and autumn. In winter and spring, Beijing was not only affected by the trajectories from the south and southeast, but was also affected by trajectories from the north and northwest. In addition, the analyses of the pressure profile of backward trajectories showed that backward trajectories, which have important influence on Beijing, were mainly distributed above 970 hPa in summer and autumn and below 950 hPa in spring and winter. This indicates that PM2.s and PMIo were strongly affected by the near surface air masses in summer and autumn and by high altitude air masses in winter and spring. Results of PSCF and CV/T analyses showed that the largest potential source areas were identified in spring, followed by winter and autumn, then summer. In addition, potential source regions of PMIo were similar to those of PM2.5. There were a clear seasonal and spatial variation of the potential source areas of Beijing and the airflow in the horizontal and vertical directions. Therefore, more effective regional emission reduction measures in Beijing＇s surrounding provinces should be implemented to reduce emissions of regional sources in different seasons.
