Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techni...Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techniques involved in the fabrication ofμLED-based devices is transfer printing.Although numerous methods have been proposed for transfer printing,improving the yield ofμLED arrays is still a formidable task.In this paper,we propose a novel method for improving the yield ofμLED arrays transferred by the stamping method,using an innovative design of piezoelectrically driven asymmetric micro-gripper.Traditional grippers are too large to manipulateμLEDs,and therefore two micro-sized cantilevers are added at the gripper tips.AμLED manipulation system is constructed based on the micro-gripper together with a three-dimensional positioning system.Experimental results using this system show that it can be used successfully to manipulateμLED arrays.展开更多
V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical conductivity.In this paper,polypyridine(PPyd)i...V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical conductivity.In this paper,polypyridine(PPyd)intercalated VO with nanoribbon structure was prepared by a simple in-situ pre-intercalation,which is noted VO-PPyd.The total density of states(TDOS)shows that after the pre-intercalation of PPyd,an intermediate energy level appears between the valence band and conduction band,which provides a step that can effectively reduce the band gap and enhance the electron conductivity.Furthermore,the density functional theory(DFT)results found that Zn^(2+)is more easily de-intercalated from the V-O skeleton,which proves that the embeddedness of PPyd improves the diffusion kinetics of Zn^(2+).Electrochemical studies have shown that VO-PPyd cathode materials exhibit excellent rate performance(high specific capacity of 465 and 192 mA h g^(-1)at 0.2 and 10 A g^(-1),respectively)and long-term cycling performance(92.7%capacity retention rate after 5300 cycles),due to their advantages in structure and composition.More importantly,the energy density of VO-PPyd//Zn at 581 and 5806 W kg^(-1)is 375 and 247 W h kg^(-1),respectively.VO-PPyd exhibits excellent electrochemical properties compared to previously reported vanadium based cathodes,which makes it highly competitive in the field of high-performance cathode materials of AZIBs.展开更多
Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the sh...Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the shut-in phase in augmenting shale oil productivity.Unlike conventional reservoirs,shale oil reservoirs exhibit characteristics such as low porosity,low permeability,and rich content of organic matter and clay minerals.Notably,the osmotic pressure effects occurring between high-salinity formation water and low-salinity fracturing fluids are significant.The current understanding of the mobilization patterns of crude oil in micro-pores during the imbibition process remains nebulous,and the mechanisms underpinning osmotic pressure effects are not fully understood.This study introduces a theoretical approach,by which a salt ion migration control equation is derived and a mathematical model for spontaneous imbibition in shale is introduced,which is able to account for both capillary and osmotic pressures.Results indicate that during the spontaneous imbibition of low-salinity fluids,osmotic effects facilitate the migration of external fluids into shale pores,thereby complementing capillary forces in displacing shale oil.When considering both capillary and osmotic pressures,the calculated imbibition depth increases by 12%compared to the case where only capillary forces are present.The salinity difference between the reservoir and the fracturing fluids significantly influences the imbibition depth.Calculations for the shutin phase reveal that the pressure between the matrix and fractures reaches a dynamic equilibrium after 28 days of shut-in.During the production phase,the maximum seepage distance in the target block is approximately 6.02 m.展开更多
BACKGROUND Perihilar cholangiocarcinoma(pCCA)has a poor prognosis and urgently needs a better predictive method.The predictive value of the age-adjusted Charlson comorbidity index(ACCI)for the long-term prognosis of p...BACKGROUND Perihilar cholangiocarcinoma(pCCA)has a poor prognosis and urgently needs a better predictive method.The predictive value of the age-adjusted Charlson comorbidity index(ACCI)for the long-term prognosis of patients with multiple malignancies was recently reported.However,pCCA is one of the most surgically difficult gastrointestinal tumors with the poorest prognosis,and the value of the ACCI for the prognosis of pCCA patients after curative resection is unclear.AIM To evaluate the prognostic value of the ACCI and to design an online clinical model for pCCA patients.METHODS Consecutive pCCA patients after curative resection between 2010 and 2019 were enrolled from a multicenter database.The patients were randomly assigned 3:1 to training and validation cohorts.In the training and validation cohorts,all patients were divided into low-,moderate-,and high-ACCI groups.Kaplan-Meier curves were used to determine the impact of the ACCI on overall survival(OS)for pCCA patients,and multivariate Cox regression analysis was used to determine the independent risk factors affecting OS.An online clinical model based on the ACCI was developed and validated.The concordance index(C-index),calibration curve,and receiver operating characteristic(ROC)curve were used to evaluate the predictive performance and fit of this model.RESULTS A total of 325 patients were included.There were 244 patients in the training cohort and 81 patients in the validation cohort.In the training cohort,116,91 and 37 patients were classified into the low-,moderate-and high-ACCI groups.The Kaplan-Meier curves showed that patients in the moderate-and high-ACCI groups had worse survival rates than those in the low-ACCI group.Multivariable analysis revealed that moderate and high ACCI scores were independently associated with OS in pCCA patients after curative resection.In addition,an online clinical model was developed that had ideal C-indexes of 0.725 and 0.675 for predicting OS in the training and validation cohorts.The calibration curve and ROC curve indicated that the model had a good fit and prediction performance.CONCLUSION A high ACCI score may predict poor long-term survival in pCCA patients after curative resection.High-risk patients screened by the ACCI-based model should be given more clinical attention in terms of the management of comorbidities and postoperative follow-up.展开更多
The rational synergy of chemical composition and spatial nanostructures of electrode materials play important roles in high-performance energy storage devices.Here,we designed pea-like MoS_(2)@NiS_(1.03)-carbon hollow...The rational synergy of chemical composition and spatial nanostructures of electrode materials play important roles in high-performance energy storage devices.Here,we designed pea-like MoS_(2)@NiS_(1.03)-carbon hollow nanofibers using a simple electrospinning and thermal treatment method.The hierarchical hollow nanofiber is composed of a nitrogen-doped carbon-coated NiS_(1.03) tube wall,in which pea-like uniformly discrete MoS_(2) nanoparticles are enclosed.As a sodium-ion battery electrode material,the MoS_(2)@NiS_(1.03)-carbon hollow nanofibers have abundant diphasic heterointerfaces,a conductive network,and appropriate volume variation-buffering spaces,which can facilitate ion diffusion kinetics,shorten the diffusion path of electrons/ion,and buffer volume expansion during Na^(+)insertion/extraction.It shows outstanding rate capacity and long-cycle performance in a sodium-ion battery.This heterogeneous hollow nanoarchitectures designing enlightens an efficacious strategy to boost the capacity and long-life stability of sodium storage performance of electrode materials.展开更多
In the Changqing Oilfield in northwest China, when traditional petroleum exploitation encounters forestry reserves or water source protection areas, sectorial well-factory design is proposed. The most distinct feature...In the Changqing Oilfield in northwest China, when traditional petroleum exploitation encounters forestry reserves or water source protection areas, sectorial well-factory design is proposed. The most distinct feature of a sectorial well-factory is the deviation of the well from the minimum horizontal principal stress, resulting in hydraulic fracture deflection after the initiation, along with possible well interference (i.e., fracture hit) and fracture coalescence in the oblique wells. Four indexes describing well deflection are then proposed according to fracture morphology. Several fracturing designs, including stage arrangement, fracturing sequences, and fracturing techniques are applied to study the feasibility of the sectorial well-factory design. The results show that the “gradual” or “sparse” stage arrangement, large injection rate, and simultaneous multifracture treatment can help to optimize the fracture morphology and stimulation design. However, the subsequent stress shadowing effect usually adversely affects the fracturing of adjacent wells. With a small initial horizontal stress difference, large injection rate and staggered stage arrangement can achieve ideal stimulation performance. Our results can provide a guidance for optimizing stimulation design in unconventional well-factory while taking into account environmental protection.展开更多
There is a significantly increasing demand of developing augmented reality and virtual reality(AR and VR) devices,where micro-LEDs(μLEDs) with a dimension of ≤ 5 μm are the key elements. Typically, μLEDs are fabri...There is a significantly increasing demand of developing augmented reality and virtual reality(AR and VR) devices,where micro-LEDs(μLEDs) with a dimension of ≤ 5 μm are the key elements. Typically, μLEDs are fabricated by dry-etching technologies, unavoidably leading to a severe degradation in optical performance as a result of dry-etching induced damages. This becomes a particularly severe issue when the dimension of LEDs is ≤ 10 μm. In order to address the fundamental challenge, the Sheffield team has proposed and then developed a direct epitaxial approach to achievingμLEDs, where the dry-etching technologies for the formation of μLED mesas are not needed anymore. This paper provides a review on this technology and then demonstrates a number of monolithically integrated devices on a single chip using this technology.展开更多
Unconventional reservoirs usually contain many weak surfaces such as faults,laminae and natural fractures,and effective activation and utilization of these weak surfaces in reservoirs can significantly improve the ext...Unconventional reservoirs usually contain many weak surfaces such as faults,laminae and natural fractures,and effective activation and utilization of these weak surfaces in reservoirs can significantly improve the extraction effect.In hydraulic fracturing,when the artificial fracture approaches the natural fracture,the natural fracture would be influenced by both the original in-situ stress field and the hydraulic fracturing-induced stress field.In this paper,the hydraulic fracturing-induced stress field is calculated based on the relative position of hydraulic fracture and natural fracture,the original in-situ stress,the net pressure inside the hydraulic fracture and the pore pressure of the formation.Furthermore,the stability model of the natural fracture is established by combining the Mohr-Coulomb rupture criterion,and extensive parametric studies are conducted to explore the impact of each parameter on the stability of the natural fracture.The validity of the proposed model is verified by comparing with the reservoir characteristics and fracturing process of the X-well 150e155 formation in the Songliao Basin.It is found that the stress field induced by the hydraulic fracture inhibits the activation of the natural fracture after the artificial fracture crossed the natural fracture.Therefore,for similar reservoirs as X-well 150e155,it is suggested to connect natural fractures with hydraulic fractures first and then activate natural fractures which can effectively utilize the natural fractures and form a complex fracture network.展开更多
BACKGROUND Breast infiltrating ductal carcinoma(BIDC)represents the largest heterotypic tumor group,and an in-depth understanding of the pathogenesis of BIDC is key to improving its prognosis.AIM To analyze the expres...BACKGROUND Breast infiltrating ductal carcinoma(BIDC)represents the largest heterotypic tumor group,and an in-depth understanding of the pathogenesis of BIDC is key to improving its prognosis.AIM To analyze the expression profiles and clinical implications of forkhead box M1(FOXM1),cyclooxygenase-2(COX-2),and glucose-regulated protein 78(GRP78)in BIDC.METHODS A total of 65 BIDC patients and 70 healthy controls who presented to our hospital between August 2019 and May 2021 were selected for analysis.The peripheral blood FOXM1,COX-2,and GRP78 levels in both groups were measured and the association between their expression profiles in BIDC was examined.Additionally,we investigated the diagnostic value of FOXM1,COX-2,and GRP78 in patients with BIDC and their correlations with clinicopathological features.Furthermore,BIDC patients were followed for 1 year to identify factors influencing patient prognosis.RESULTS The levels of FOXM1,COX-2,and GRP78 were significantly higher in BIDC patients compared to healthy controls(P<0.05),and a positive correlation was observed among them(P<0.05).Receiver operating characteristic analysis demonstrated that FOXM1,COX-2,and GRP78 had excellent diagnostic value in predicting the occurrence of BIDC(P<0.05).Subsequently,we found significant differences in FOXM1,COX-2,and GRP78 levels among patients with different histological grades and metastasis statuses(with vs without)(P<0.05).Cox analysis revealed that FOXM1,COX-2,GRP78,increased histological grade,and the presence of tumor metastasis were independent risk factors for prognostic death in BIDC(P<0.001).CONCLUSION FOXM1,COX-2,and GRP78 exhibit abnormally high expression in BIDC,promoting malignant tumor development and closely correlating with prognosis.These findings hold significant research implications for the future diagnosis and treatment of BIDC.展开更多
Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strai...Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strain U32 comprising 10 236 715 base pairs, is one of the largest prokaryotic genomes ever sequenced so far. Unlike the linear topology found in streptomycetes, this chromosome is circular, particularly similar to that of Saccharopolyspora erythraea and Nocardia farcinica, representing their close relationship in phylogeny and taxonomy. Although the predicted 9 228 protein-coding genes in the A. mediterranei genome shared the greatest number of orthologs with those of S. erythraea, it was unexpectedly followed by Streptomyces coelicolor rather than N. farcinica, indicating the distinct metabolic characteristics evolved via adaptation to diverse ecological niches. Besides a core region analogous to that common in streptomycetes, a novel 'quasicore' with typical core characteristics is defined within the non-core region, where 21 out of the total 26 gene clusters for secondary metabolite production are located. The rifamycin biosynthesis gene cluster located in the core encodes a cytochrome P450 enzyme essential for the conversion of rifamycin SV to B, revealed by comparing to the highly homologous cluster of the rifamycin B-producing strain S699 and further confirmed by genetic complementation. The genomic information of A. mediterranei demonstrates a metabolic network orchestrated not only for extensive utilization of various carbon sources and inorganic nitrogen compounds but also for effective funneling of metabolic intermediates into the secondary antibiotic synthesis process under the control of a seemingly complex regulatory mechanism.展开更多
BACKGROUND Postoperative morbidity after curative resection for hilar cholangiocarcinoma(HCCA)is common;however,whether it has an impact on oncological prognosis is unknown.AIM To evaluate the influence of postoperati...BACKGROUND Postoperative morbidity after curative resection for hilar cholangiocarcinoma(HCCA)is common;however,whether it has an impact on oncological prognosis is unknown.AIM To evaluate the influence of postoperative morbidity on tumor recurrence and mortality after curative resection for HCCA.METHODS Patients with recently diagnosed HCCA who had undergone curative resection between January 2010 and December 2017 at The First Affiliated Hospital of Army Medical University in China were enrolled.The independent risk factors for morbidity in the 30 d after surgery were investigated,and links between postoperative morbidity and patient characteristics and outcomes were assessed.Postoperative morbidities were divided into five grades based on the Clavien-Dindo classification,and major morbidities were defined as Clavien-Dindo≥3.Univariate and multivariate Cox regression analyses were used to evaluate the risk factors for recurrence-free survival(RFS)and overall survival(OS).RESULTS Postoperative morbidity occurred in 146 out of 239 patients(61.1%).Multivariate logistic regression revealed that cirrhosis, intraoperative blood loss > 500 mL, diabetes mellitus,and obesity were independent risk factors. Postoperative morbidity was associated with decreasedOS and RFS (OS: 18.0 mo vs 31.0 mo, respectively, P = 0.003;RFS: 16.0 mo vs 26.0 mo, respectively,P = 0.002). Multivariate Cox regression analysis indicated that postoperative morbidity wasindependently associated with decreased OS [hazard ratios (HR): 1.557, 95% confidence interval(CI): 1.119-2.167, P = 0.009] and RFS (HR: 1.535, 95%CI: 1.117-2.108, P = 0.008). Moreover, majormorbidity was independently associated with decreased OS (HR: 2.175;95%CI: 1.470-3.216, P <0.001) and RFS (HR: 2.054;95%CI: 1.400-3.014, P < 0.001) after curative resection for HCCA.CONCLUSIONPostoperative morbidity (especially major morbidity) may be an independent risk factor forunfavorable prognosis in HCCA patients following curative resection.展开更多
Xinjiang is the largest semi-arid and arid region in China, and drip irrigation under plastic mulch is widely used in this water-limited area. Quantifying carbon and water fluxes as well as investigating their environ...Xinjiang is the largest semi-arid and arid region in China, and drip irrigation under plastic mulch is widely used in this water-limited area. Quantifying carbon and water fluxes as well as investigating their environ- mental drivers over cotton fields is critical for understanding regional carbon and water budgets in Xinjiang, the largest cotton production basin of China. In this study, an eddy covariance (EC) technique was used to measure the carbon and water fluxes of cotton field under drip irrigation with plastic mulch in the growing seasons of 2009, 2010, 2012 and 2013 at Wulanwusu Agrometeorological Experiment Station, a representative oasis cropland in northern Xinjiang. The diurnal patterns of gross primary production (GPP), net ecosystem exchange (NEE) and evapotran-spiration (ET) showed obviously sinusoidal variations from June to September, while the diurnal ecosystem respiration (Res) was stable between daytime and nighttime. The daytime hourly GPP and ET displayed asymptotic rela-tionships with net solar radiation (Rnet), while showed concave patterns with raising vapor pressure deficit (VPD) and air temperature (Ta). The increases in hourly GPP and ET towards the maximum occurred over half ranges of VPD and Ta. The seasonal variations of GPP, NEE and ET were close to the cotton phenology, which almost reached the peak value in July. The cumulative GPP averaged 816.2±55.0 g C/m^2 in the growing season (from April to October), and more than half of GPP was partitioned into NEE (mean value of -478.6±41.4 g C/m^2). The mean seasonal ET was 501.3±13.9 mm, and the mean water use efficiency (WUE) was 1.0+0.1 (mg C/g H2O)/d. The agro-ecosystem behaved as a carbon sink from squaring to harvest period, while it acted as a carbon source before the squaring time as well as after the harvest time.展开更多
Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals.However,few research have reported the effects of...Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals.However,few research have reported the effects of BA and BS on fermentation characteristics and bacterial community successions of whole-plant corn silage during ensiling.If the BA and BS inoculants have positive effects on silages,then they could not only improve fermentation characteristics,but also deliver BA or BS viable cells to ruminants,which would play its probiotic effect.Therefore,the objectives of this study were to investigate the effects of BA and BS on the fermentation,chemical characteristics,bacterial community and their metabolic pathway of whole-plant corn silage.Results:Freshly chopped whole-plant corn was inoculated without or with BA and BS,respectively,and ensiled for1,3,7,14 and 60 d.Results showed that BA and BS inoculations increased lactic acid concentrations of whole-plant corn silages compared with control,and BA inoculation decreased acetic acid concentrations,whereas BS inoculation decreased fiber contents and increased crude protein(CP)content.Higher water-soluble carbohydrate contents and lower starch contents were observed in BA-and BS-inoculated silages compared with that in control.The decreased CP content and increased non-protein nitrogen content were observed in BA-inoculated silage,which was consistent with the higher amino acid metabolism abundances observed in BA-inoculated silage.In addition,it was noteworthy that BA and BS inoculations increased the metabolism of cofactors and vitamins,and decreased the relative abundances of drug resistance:antimicrobial pathways.We also found that the bacterial metabolism pathways were clearly separated into three clusters based on the ensiling times of whole-plant corn silage in the present study.There were no significant differences in bacterial community compositions among the three groups during ensiling.However,BA and BS inoculations decreased the relative abundances of undesirable bacteria such as Acetobacter and Acinetobacter.Conclusion:Our findings suggested that the BS strain was more suitable as silage inoculants than the BA strain in whole-plant corn silage in this study.展开更多
Background Myocardial infarction (MI) has likely contributed to the increased prevalence of heart failure (HF). As a result of re- duced cardiac function, splanchnic blood flow decreases, causing ischemia in villi...Background Myocardial infarction (MI) has likely contributed to the increased prevalence of heart failure (HF). As a result of re- duced cardiac function, splanchnic blood flow decreases, causing ischemia in villi and damage to the intestinal barrier. The induction of heme oxygenase-1 (HO-1) could prevent, or lessen the effects of stress and inflammation. Thus, the effect and mechanism thereof of HO-1 on the intestines of rats with HF was investigated. Methods Male Wistar rats with heart failure through ligation of the left coronary artery were identified with an left ventricular ejection fraction of 〈 45% through echocardiography and then divided into various experimental groups based on the type of peritoneal injection they received [MI: saline; MI + Cobalt protoporphyrin (CoPP): CoPP solution; and MI + Tin mesoporphyrin IX dichloride (SnMP): SnMP solution]. The control group was comprised of rats without coronary ligation. Echocardiogra- phy was performed before ligation for a baseline and eight weeks after ligation in order to evaluate the cardiac function of the rats. The bac- terial translocation (BT) incidence, mesenteric microcirculation, amount of endotoxins in the vein serum, ileum levels of HO- 1, carbon oxide (CO), nitric oxide (NO), intedeuldn (IL)-10, turnour necrosis factor-et (TNF-ct), and the ileum morphology were determined eight weeks after the operation. Results The rats receiving MI + CoPP injections exhibited a recovery in cardiac function, an amelioration of mesenteric microcirculation and change in morphology, a lower BT incidence, a reduction in serum and ileac NO and TNF-ct levels, and an elevation in ileac HO-1, CO, and interleukin-10 ([L-10) levels compared to the MI group (P 〈 0.05). The rats that received the MI + SnMP injections exhibited results inverse to the MI (P 〈 0.05) group. Conclusions HO-1 exerted a protective effect on the intestines of rats with HF by inhibiting the inflammation and amelioration of microcirculation through the CO pathway. This protective effect could be independent from the recovery of cardiac function.展开更多
基金support from the Scientific Research Program of the Tianjin Education Commission(No.2019ZD08).
文摘Micro-LEDs(μLEDs)have advantages in terms of brightness,power consumption,and response speed.In addition,they can also be used as micro-sensors implanted in the body via flexible electronic skin.One of the key techniques involved in the fabrication ofμLED-based devices is transfer printing.Although numerous methods have been proposed for transfer printing,improving the yield ofμLED arrays is still a formidable task.In this paper,we propose a novel method for improving the yield ofμLED arrays transferred by the stamping method,using an innovative design of piezoelectrically driven asymmetric micro-gripper.Traditional grippers are too large to manipulateμLEDs,and therefore two micro-sized cantilevers are added at the gripper tips.AμLED manipulation system is constructed based on the micro-gripper together with a three-dimensional positioning system.Experimental results using this system show that it can be used successfully to manipulateμLED arrays.
基金supported by the National Natural Science Foundation of China (21676036)the Natural Science Foundation of Chongqing (CSTB2023NSCQ-MSX0580)the Graduate Research and Innovation Foundation of Chongqing (CYB22043 and CYS22073)。
文摘V_(3)O_(7)·H_(2)O(VO)is a high capacity cathode material in the field of aqueous zinc ion batteries(AZIBs),but it is limited by slow ion migration and low electrical conductivity.In this paper,polypyridine(PPyd)intercalated VO with nanoribbon structure was prepared by a simple in-situ pre-intercalation,which is noted VO-PPyd.The total density of states(TDOS)shows that after the pre-intercalation of PPyd,an intermediate energy level appears between the valence band and conduction band,which provides a step that can effectively reduce the band gap and enhance the electron conductivity.Furthermore,the density functional theory(DFT)results found that Zn^(2+)is more easily de-intercalated from the V-O skeleton,which proves that the embeddedness of PPyd improves the diffusion kinetics of Zn^(2+).Electrochemical studies have shown that VO-PPyd cathode materials exhibit excellent rate performance(high specific capacity of 465 and 192 mA h g^(-1)at 0.2 and 10 A g^(-1),respectively)and long-term cycling performance(92.7%capacity retention rate after 5300 cycles),due to their advantages in structure and composition.More importantly,the energy density of VO-PPyd//Zn at 581 and 5806 W kg^(-1)is 375 and 247 W h kg^(-1),respectively.VO-PPyd exhibits excellent electrochemical properties compared to previously reported vanadium based cathodes,which makes it highly competitive in the field of high-performance cathode materials of AZIBs.
基金China National Petroleum Corporation’s Fourteenth Five-Year Plan’s Prospective Fundamental Project on‘Research on Key Technologies and Equipment for Reservoir Reconstruction’(2021DJ45).
文摘Following large-scale volume fracturing in shale oil reservoirs,well shut-in measures are generally employed.Laboratory tests and field trials have underscored the efficacy of fracturing fluid imbibition during the shut-in phase in augmenting shale oil productivity.Unlike conventional reservoirs,shale oil reservoirs exhibit characteristics such as low porosity,low permeability,and rich content of organic matter and clay minerals.Notably,the osmotic pressure effects occurring between high-salinity formation water and low-salinity fracturing fluids are significant.The current understanding of the mobilization patterns of crude oil in micro-pores during the imbibition process remains nebulous,and the mechanisms underpinning osmotic pressure effects are not fully understood.This study introduces a theoretical approach,by which a salt ion migration control equation is derived and a mathematical model for spontaneous imbibition in shale is introduced,which is able to account for both capillary and osmotic pressures.Results indicate that during the spontaneous imbibition of low-salinity fluids,osmotic effects facilitate the migration of external fluids into shale pores,thereby complementing capillary forces in displacing shale oil.When considering both capillary and osmotic pressures,the calculated imbibition depth increases by 12%compared to the case where only capillary forces are present.The salinity difference between the reservoir and the fracturing fluids significantly influences the imbibition depth.Calculations for the shutin phase reveal that the pressure between the matrix and fractures reaches a dynamic equilibrium after 28 days of shut-in.During the production phase,the maximum seepage distance in the target block is approximately 6.02 m.
基金Supported by National Natural Science Foundation of China,No. 81874211Chongqing Technology Innovation and Application Development Special Key Project,No. CSTC2021jscx-gksb-N0009
文摘BACKGROUND Perihilar cholangiocarcinoma(pCCA)has a poor prognosis and urgently needs a better predictive method.The predictive value of the age-adjusted Charlson comorbidity index(ACCI)for the long-term prognosis of patients with multiple malignancies was recently reported.However,pCCA is one of the most surgically difficult gastrointestinal tumors with the poorest prognosis,and the value of the ACCI for the prognosis of pCCA patients after curative resection is unclear.AIM To evaluate the prognostic value of the ACCI and to design an online clinical model for pCCA patients.METHODS Consecutive pCCA patients after curative resection between 2010 and 2019 were enrolled from a multicenter database.The patients were randomly assigned 3:1 to training and validation cohorts.In the training and validation cohorts,all patients were divided into low-,moderate-,and high-ACCI groups.Kaplan-Meier curves were used to determine the impact of the ACCI on overall survival(OS)for pCCA patients,and multivariate Cox regression analysis was used to determine the independent risk factors affecting OS.An online clinical model based on the ACCI was developed and validated.The concordance index(C-index),calibration curve,and receiver operating characteristic(ROC)curve were used to evaluate the predictive performance and fit of this model.RESULTS A total of 325 patients were included.There were 244 patients in the training cohort and 81 patients in the validation cohort.In the training cohort,116,91 and 37 patients were classified into the low-,moderate-and high-ACCI groups.The Kaplan-Meier curves showed that patients in the moderate-and high-ACCI groups had worse survival rates than those in the low-ACCI group.Multivariable analysis revealed that moderate and high ACCI scores were independently associated with OS in pCCA patients after curative resection.In addition,an online clinical model was developed that had ideal C-indexes of 0.725 and 0.675 for predicting OS in the training and validation cohorts.The calibration curve and ROC curve indicated that the model had a good fit and prediction performance.CONCLUSION A high ACCI score may predict poor long-term survival in pCCA patients after curative resection.High-risk patients screened by the ACCI-based model should be given more clinical attention in terms of the management of comorbidities and postoperative follow-up.
基金financially supported by the National Natural Science Foundation of China(NSFC)(Grant Nos.22175007,21975007,52172080,and 22005012)the National Natural Science Foundation for Outstanding Youth Foundation,the Fundamental Research Funds for the Central Universities,the National Program for Support of Top-notch Young Professionalsthe 111 project(Grant No.B14009).
文摘The rational synergy of chemical composition and spatial nanostructures of electrode materials play important roles in high-performance energy storage devices.Here,we designed pea-like MoS_(2)@NiS_(1.03)-carbon hollow nanofibers using a simple electrospinning and thermal treatment method.The hierarchical hollow nanofiber is composed of a nitrogen-doped carbon-coated NiS_(1.03) tube wall,in which pea-like uniformly discrete MoS_(2) nanoparticles are enclosed.As a sodium-ion battery electrode material,the MoS_(2)@NiS_(1.03)-carbon hollow nanofibers have abundant diphasic heterointerfaces,a conductive network,and appropriate volume variation-buffering spaces,which can facilitate ion diffusion kinetics,shorten the diffusion path of electrons/ion,and buffer volume expansion during Na^(+)insertion/extraction.It shows outstanding rate capacity and long-cycle performance in a sodium-ion battery.This heterogeneous hollow nanoarchitectures designing enlightens an efficacious strategy to boost the capacity and long-life stability of sodium storage performance of electrode materials.
基金funded by the National Natural Science Foundation of China(42077247,52104029)the Fundamental Research Funds for the Central Universities.
文摘In the Changqing Oilfield in northwest China, when traditional petroleum exploitation encounters forestry reserves or water source protection areas, sectorial well-factory design is proposed. The most distinct feature of a sectorial well-factory is the deviation of the well from the minimum horizontal principal stress, resulting in hydraulic fracture deflection after the initiation, along with possible well interference (i.e., fracture hit) and fracture coalescence in the oblique wells. Four indexes describing well deflection are then proposed according to fracture morphology. Several fracturing designs, including stage arrangement, fracturing sequences, and fracturing techniques are applied to study the feasibility of the sectorial well-factory design. The results show that the “gradual” or “sparse” stage arrangement, large injection rate, and simultaneous multifracture treatment can help to optimize the fracture morphology and stimulation design. However, the subsequent stress shadowing effect usually adversely affects the fracturing of adjacent wells. With a small initial horizontal stress difference, large injection rate and staggered stage arrangement can achieve ideal stimulation performance. Our results can provide a guidance for optimizing stimulation design in unconventional well-factory while taking into account environmental protection.
基金Project supported by the Engineering and Physical Sciences Research Council (EPSRC),U.K.,via EP/P006973/1,EP/T013001/1,and EP/M015181/1。
文摘There is a significantly increasing demand of developing augmented reality and virtual reality(AR and VR) devices,where micro-LEDs(μLEDs) with a dimension of ≤ 5 μm are the key elements. Typically, μLEDs are fabricated by dry-etching technologies, unavoidably leading to a severe degradation in optical performance as a result of dry-etching induced damages. This becomes a particularly severe issue when the dimension of LEDs is ≤ 10 μm. In order to address the fundamental challenge, the Sheffield team has proposed and then developed a direct epitaxial approach to achievingμLEDs, where the dry-etching technologies for the formation of μLED mesas are not needed anymore. This paper provides a review on this technology and then demonstrates a number of monolithically integrated devices on a single chip using this technology.
基金funded by the subprojects of the National Key R&D Program of China(2020YFA0710600)the NSFC(National Natural Science Foundation of China,grant 42374132).
文摘Unconventional reservoirs usually contain many weak surfaces such as faults,laminae and natural fractures,and effective activation and utilization of these weak surfaces in reservoirs can significantly improve the extraction effect.In hydraulic fracturing,when the artificial fracture approaches the natural fracture,the natural fracture would be influenced by both the original in-situ stress field and the hydraulic fracturing-induced stress field.In this paper,the hydraulic fracturing-induced stress field is calculated based on the relative position of hydraulic fracture and natural fracture,the original in-situ stress,the net pressure inside the hydraulic fracture and the pore pressure of the formation.Furthermore,the stability model of the natural fracture is established by combining the Mohr-Coulomb rupture criterion,and extensive parametric studies are conducted to explore the impact of each parameter on the stability of the natural fracture.The validity of the proposed model is verified by comparing with the reservoir characteristics and fracturing process of the X-well 150e155 formation in the Songliao Basin.It is found that the stress field induced by the hydraulic fracture inhibits the activation of the natural fracture after the artificial fracture crossed the natural fracture.Therefore,for similar reservoirs as X-well 150e155,it is suggested to connect natural fractures with hydraulic fractures first and then activate natural fractures which can effectively utilize the natural fractures and form a complex fracture network.
文摘BACKGROUND Breast infiltrating ductal carcinoma(BIDC)represents the largest heterotypic tumor group,and an in-depth understanding of the pathogenesis of BIDC is key to improving its prognosis.AIM To analyze the expression profiles and clinical implications of forkhead box M1(FOXM1),cyclooxygenase-2(COX-2),and glucose-regulated protein 78(GRP78)in BIDC.METHODS A total of 65 BIDC patients and 70 healthy controls who presented to our hospital between August 2019 and May 2021 were selected for analysis.The peripheral blood FOXM1,COX-2,and GRP78 levels in both groups were measured and the association between their expression profiles in BIDC was examined.Additionally,we investigated the diagnostic value of FOXM1,COX-2,and GRP78 in patients with BIDC and their correlations with clinicopathological features.Furthermore,BIDC patients were followed for 1 year to identify factors influencing patient prognosis.RESULTS The levels of FOXM1,COX-2,and GRP78 were significantly higher in BIDC patients compared to healthy controls(P<0.05),and a positive correlation was observed among them(P<0.05).Receiver operating characteristic analysis demonstrated that FOXM1,COX-2,and GRP78 had excellent diagnostic value in predicting the occurrence of BIDC(P<0.05).Subsequently,we found significant differences in FOXM1,COX-2,and GRP78 levels among patients with different histological grades and metastasis statuses(with vs without)(P<0.05).Cox analysis revealed that FOXM1,COX-2,GRP78,increased histological grade,and the presence of tumor metastasis were independent risk factors for prognostic death in BIDC(P<0.001).CONCLUSION FOXM1,COX-2,and GRP78 exhibit abnormally high expression in BIDC,promoting malignant tumor development and closely correlating with prognosis.These findings hold significant research implications for the future diagnosis and treatment of BIDC.
基金This paper is dedicated to the late Professor JS Chiao, who initiated the research in China for rifamycin production employing A. mediterranei more than 30 years ago and who continued the endeavor to resolve the mechanism of the 'nitrate stimulating effect' up to the last breath of his life. This work was supported by the National Natural Science Foundation of China (30830002), the National High Technology Research and Development Program of China (2007AA021301, 2007AA021503), and the Research Unit Fund of Li Ka Shing Institute of Health Sciences (7103506).
文摘Amycolatopsis mediterranei is used for industry-scale production of rifamycin, which plays a vital role in antimyco- bacterial therapy. As the first sequenced genome of the genus Amycolatopsis, the chromosome of strain U32 comprising 10 236 715 base pairs, is one of the largest prokaryotic genomes ever sequenced so far. Unlike the linear topology found in streptomycetes, this chromosome is circular, particularly similar to that of Saccharopolyspora erythraea and Nocardia farcinica, representing their close relationship in phylogeny and taxonomy. Although the predicted 9 228 protein-coding genes in the A. mediterranei genome shared the greatest number of orthologs with those of S. erythraea, it was unexpectedly followed by Streptomyces coelicolor rather than N. farcinica, indicating the distinct metabolic characteristics evolved via adaptation to diverse ecological niches. Besides a core region analogous to that common in streptomycetes, a novel 'quasicore' with typical core characteristics is defined within the non-core region, where 21 out of the total 26 gene clusters for secondary metabolite production are located. The rifamycin biosynthesis gene cluster located in the core encodes a cytochrome P450 enzyme essential for the conversion of rifamycin SV to B, revealed by comparing to the highly homologous cluster of the rifamycin B-producing strain S699 and further confirmed by genetic complementation. The genomic information of A. mediterranei demonstrates a metabolic network orchestrated not only for extensive utilization of various carbon sources and inorganic nitrogen compounds but also for effective funneling of metabolic intermediates into the secondary antibiotic synthesis process under the control of a seemingly complex regulatory mechanism.
基金Supported by National Natural Science Foundation of China, No.81874211Personalized Training of Key Support Objects for The Talent People of The Army Medical University, No.XZ-2019-505-014
文摘BACKGROUND Postoperative morbidity after curative resection for hilar cholangiocarcinoma(HCCA)is common;however,whether it has an impact on oncological prognosis is unknown.AIM To evaluate the influence of postoperative morbidity on tumor recurrence and mortality after curative resection for HCCA.METHODS Patients with recently diagnosed HCCA who had undergone curative resection between January 2010 and December 2017 at The First Affiliated Hospital of Army Medical University in China were enrolled.The independent risk factors for morbidity in the 30 d after surgery were investigated,and links between postoperative morbidity and patient characteristics and outcomes were assessed.Postoperative morbidities were divided into five grades based on the Clavien-Dindo classification,and major morbidities were defined as Clavien-Dindo≥3.Univariate and multivariate Cox regression analyses were used to evaluate the risk factors for recurrence-free survival(RFS)and overall survival(OS).RESULTS Postoperative morbidity occurred in 146 out of 239 patients(61.1%).Multivariate logistic regression revealed that cirrhosis, intraoperative blood loss > 500 mL, diabetes mellitus,and obesity were independent risk factors. Postoperative morbidity was associated with decreasedOS and RFS (OS: 18.0 mo vs 31.0 mo, respectively, P = 0.003;RFS: 16.0 mo vs 26.0 mo, respectively,P = 0.002). Multivariate Cox regression analysis indicated that postoperative morbidity wasindependently associated with decreased OS [hazard ratios (HR): 1.557, 95% confidence interval(CI): 1.119-2.167, P = 0.009] and RFS (HR: 1.535, 95%CI: 1.117-2.108, P = 0.008). Moreover, majormorbidity was independently associated with decreased OS (HR: 2.175;95%CI: 1.470-3.216, P <0.001) and RFS (HR: 2.054;95%CI: 1.400-3.014, P < 0.001) after curative resection for HCCA.CONCLUSIONPostoperative morbidity (especially major morbidity) may be an independent risk factor forunfavorable prognosis in HCCA patients following curative resection.
基金supported by the West Light Foundation of the Chinese Academy of Sciences (XBBS201110)the National Natural Science Foundation of China (41101101)the Chinese Academy of Sciences Key Deployment Project (KZZDEW-08-02-02)
文摘Xinjiang is the largest semi-arid and arid region in China, and drip irrigation under plastic mulch is widely used in this water-limited area. Quantifying carbon and water fluxes as well as investigating their environ- mental drivers over cotton fields is critical for understanding regional carbon and water budgets in Xinjiang, the largest cotton production basin of China. In this study, an eddy covariance (EC) technique was used to measure the carbon and water fluxes of cotton field under drip irrigation with plastic mulch in the growing seasons of 2009, 2010, 2012 and 2013 at Wulanwusu Agrometeorological Experiment Station, a representative oasis cropland in northern Xinjiang. The diurnal patterns of gross primary production (GPP), net ecosystem exchange (NEE) and evapotran-spiration (ET) showed obviously sinusoidal variations from June to September, while the diurnal ecosystem respiration (Res) was stable between daytime and nighttime. The daytime hourly GPP and ET displayed asymptotic rela-tionships with net solar radiation (Rnet), while showed concave patterns with raising vapor pressure deficit (VPD) and air temperature (Ta). The increases in hourly GPP and ET towards the maximum occurred over half ranges of VPD and Ta. The seasonal variations of GPP, NEE and ET were close to the cotton phenology, which almost reached the peak value in July. The cumulative GPP averaged 816.2±55.0 g C/m^2 in the growing season (from April to October), and more than half of GPP was partitioned into NEE (mean value of -478.6±41.4 g C/m^2). The mean seasonal ET was 501.3±13.9 mm, and the mean water use efficiency (WUE) was 1.0+0.1 (mg C/g H2O)/d. The agro-ecosystem behaved as a carbon sink from squaring to harvest period, while it acted as a carbon source before the squaring time as well as after the harvest time.
基金funded by National Natural Science Foundation of China(project no.31872417)。
文摘Background:Bacillus amyloliquefaciens(BA)and Bacillus subtilis(BS)are usually used as feed supplements directly or bacterial inoculants in biological feeds for animals.However,few research have reported the effects of BA and BS on fermentation characteristics and bacterial community successions of whole-plant corn silage during ensiling.If the BA and BS inoculants have positive effects on silages,then they could not only improve fermentation characteristics,but also deliver BA or BS viable cells to ruminants,which would play its probiotic effect.Therefore,the objectives of this study were to investigate the effects of BA and BS on the fermentation,chemical characteristics,bacterial community and their metabolic pathway of whole-plant corn silage.Results:Freshly chopped whole-plant corn was inoculated without or with BA and BS,respectively,and ensiled for1,3,7,14 and 60 d.Results showed that BA and BS inoculations increased lactic acid concentrations of whole-plant corn silages compared with control,and BA inoculation decreased acetic acid concentrations,whereas BS inoculation decreased fiber contents and increased crude protein(CP)content.Higher water-soluble carbohydrate contents and lower starch contents were observed in BA-and BS-inoculated silages compared with that in control.The decreased CP content and increased non-protein nitrogen content were observed in BA-inoculated silage,which was consistent with the higher amino acid metabolism abundances observed in BA-inoculated silage.In addition,it was noteworthy that BA and BS inoculations increased the metabolism of cofactors and vitamins,and decreased the relative abundances of drug resistance:antimicrobial pathways.We also found that the bacterial metabolism pathways were clearly separated into three clusters based on the ensiling times of whole-plant corn silage in the present study.There were no significant differences in bacterial community compositions among the three groups during ensiling.However,BA and BS inoculations decreased the relative abundances of undesirable bacteria such as Acetobacter and Acinetobacter.Conclusion:Our findings suggested that the BS strain was more suitable as silage inoculants than the BA strain in whole-plant corn silage in this study.
文摘Background Myocardial infarction (MI) has likely contributed to the increased prevalence of heart failure (HF). As a result of re- duced cardiac function, splanchnic blood flow decreases, causing ischemia in villi and damage to the intestinal barrier. The induction of heme oxygenase-1 (HO-1) could prevent, or lessen the effects of stress and inflammation. Thus, the effect and mechanism thereof of HO-1 on the intestines of rats with HF was investigated. Methods Male Wistar rats with heart failure through ligation of the left coronary artery were identified with an left ventricular ejection fraction of 〈 45% through echocardiography and then divided into various experimental groups based on the type of peritoneal injection they received [MI: saline; MI + Cobalt protoporphyrin (CoPP): CoPP solution; and MI + Tin mesoporphyrin IX dichloride (SnMP): SnMP solution]. The control group was comprised of rats without coronary ligation. Echocardiogra- phy was performed before ligation for a baseline and eight weeks after ligation in order to evaluate the cardiac function of the rats. The bac- terial translocation (BT) incidence, mesenteric microcirculation, amount of endotoxins in the vein serum, ileum levels of HO- 1, carbon oxide (CO), nitric oxide (NO), intedeuldn (IL)-10, turnour necrosis factor-et (TNF-ct), and the ileum morphology were determined eight weeks after the operation. Results The rats receiving MI + CoPP injections exhibited a recovery in cardiac function, an amelioration of mesenteric microcirculation and change in morphology, a lower BT incidence, a reduction in serum and ileac NO and TNF-ct levels, and an elevation in ileac HO-1, CO, and interleukin-10 ([L-10) levels compared to the MI group (P 〈 0.05). The rats that received the MI + SnMP injections exhibited results inverse to the MI (P 〈 0.05) group. Conclusions HO-1 exerted a protective effect on the intestines of rats with HF by inhibiting the inflammation and amelioration of microcirculation through the CO pathway. This protective effect could be independent from the recovery of cardiac function.