Unreduced gametes through chromosome doubling play a major role in the process of plant polyploidization.Our previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce th...Unreduced gametes through chromosome doubling play a major role in the process of plant polyploidization.Our previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce the 2n pollen formation by high temperature treatment.This study focused on the optimization of the 2n pollen induction technique and the mechanisms of high temperature-induced2n pollen formation in C.oleifera.We found that the optimal protocol for inducing 2n pollen via high temperature was to perform 45℃with4 h at the prophaseⅠstage of the pollen mother cells(PMCs).Meanwhile,high temperature significantly decreased the yield and fertility of2n pollen.Through the observation of meiosis,abnormal chromosome and cytological behaviour was discovered under high-temperature treatment,and we confirmed that the formation of 2n pollen is caused by abnormal cell plate.Based on weighted gene co-expression network analysis,fifteen hub genes related to cell cycle control were identified.After male flower buds were exposed to heat shock,polygalacturonase gene(CoPGX3)was significantly upregulated.We inferred that high temperature causes the CoPGX3 gene to be overexpressed and that CoPGX3 is redistributed into the cytosol where it degrades cytoplasmic pectin,which leads to an abnormal cell plate.Furthermore,abnormal cytokinesis resulted in the formation of dyads and triads,and PMCs divided to produce 2n pollen.Our findings provide new insights into the mechanism of 2n pollen induced by high temperature in a woody plant and lay a foundation for further ploidy breeding of C.oleifera.展开更多
Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the a...Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the advantages, disadvantages, and potential limitations of several main methods from both theoretical and practical perspectives. A variant of the existing method called the free spectral range(FSR) modulation method is proposed and compared with three other finesse measurement methods, i.e., the fast-switching cavity ring-down(CRD) method, the rapidly swept-frequency(SF) CRD method, and the ringing effect method. A high-power OEC platform with a high finesse of approximately 16000 is built and measured with the four methods. The performance of these methods is compared, and the results show that the FSR modulation method and the fast-switching CRD method are more suitable and accurate than the other two methods for high-finesse OEC measurements. The CRD method and the ringing effect method can be implemented in open loop using simple equipment and are easy to perform. Additionally, recommendations for selecting finesse measurement methods under different conditions are proposed, which benefit the development of OEC and its applications.展开更多
A three-dimensional, two-temperature(2T) model of a lamellar cathode arc is constructed,drawing upon the conservation equations for mass, momentum, electron energy, and heavy particle energy, in addition to Maxwell...A three-dimensional, two-temperature(2T) model of a lamellar cathode arc is constructed,drawing upon the conservation equations for mass, momentum, electron energy, and heavy particle energy, in addition to Maxwell's equations. The model aims to elucidate how the physical properties of electrons and heavy particles affect heat transfer and fluid flow in a lamellar cathode arc. This is achieved by solving and comparing the fields of electron temperature,heavy particle temperature, fluid flow, current density, and Lorentz force distribution under varying welding currents. The results show that the guiding effect of the lamellar cathode on current density, the inertial drag effect of moving arc, and the attraction effect of Lorentz force at the lamellar cathode tip primarily govern the distribution of the arc's physical fields. The guiding effect localizes the current density to the front end of the lamellar cathode, particularly where the discharge gap is minimal. Both the inertial drag effect and the attraction effect of Lorentz force direct arc flow toward its periphery. Under the influence of the aforementioned factors, the physical fields of the lamellar cathode arc undergo expansion and shift counter to the arc's direction of motion. A reduction in welding current substantially weakens the guiding effect,causing the arc's physical fields to deviate further in the direction opposite to the arc motion. In comparison with a cylindrical cathode arc, the physical fields of the lamellar cathode arc are markedly expanded, leading to a reduction in current density, electron temperature, heavy particle temperature, cathode jet flow velocity, and Lorentz force.展开更多
BACKGROUND Chronic renal failure(CRF) patients are predisposed to arrhythmias, while the detailed mechanisms are unclear. We hypothesized the chronic inflammatory state of CRF patients may lead to cardiac sympathetic ...BACKGROUND Chronic renal failure(CRF) patients are predisposed to arrhythmias, while the detailed mechanisms are unclear. We hypothesized the chronic inflammatory state of CRF patients may lead to cardiac sympathetic remodeling, increasing the incidence of ventricular arrhythmia(VA) and sudden cardiac death. And explored the role of atorvastatin and etanercept in this process.METHODS A total of 48 rats were randomly divided into sham operation group(Sham group), CRF group, CRF + atorvastatin group(CRF + statin group), and CRF + etanercept group(CRF + rhTNFR-Fcgroup). Sympathetic nerve remodeling was assessed by immunofluorescence of growth-associated protein 43(GAP-43) and tyrosine hydroxylase positive area fraction. Electrophysiological testing was performed to assess the incidence of VA by assessing the ventricular effective refractory period and ventricular fibrillation threshold. The levels of tumor necrosis factor-alpha(TNF-α) and interleukin-1beta were determined by Western blotting and enzyme-linked immunosorbent assay.RESULTS Echocardiogram showed that compared with the Sham group, left ventricular end-systolic diameter and ventricular weight/body weight ratio were significantly higher in the CRF group. Hematoxylin-eosin and Masson staining indicated that myocardial fibers were broken, disordered, and fibrotic in the CRF group. Western blotting, enzyme-linked immunosorbent assay,immunofluorescence and electrophysiological examination suggested that compared with the Sham group, GAP-43 and TNF-α proteins were significantly upregulated, GAP-43 and tyrosine hydroxylase positive nerve fiber area was increased, and ventricular fibrillation threshold was significantly decreased in the CRF group. The above effects were inhibited in the CRF + statin group and the CRF + rhTNFR-Fcgroup.CONCLUSIONS In CRF rats, TNF-α was upregulated, cardiac sympathetic remodeling was more severe, and the nephrogenic cardiac sympathetic remodeling existed. Atorvastatin and etanercept could downregulate the expression of TNF-α or inhibit its activity, thus inhibited the above effects, and reduced the occurrence of VA and sudden cardiac death.展开更多
Green hydrogen is urgently required for sustainable development of human beings and rational construction of heterostructures holds great promising for photocatalytic hydrogen generation.Herein,2D/2D WSe_(2)/ZnIn_(2)S...Green hydrogen is urgently required for sustainable development of human beings and rational construction of heterostructures holds great promising for photocatalytic hydrogen generation.Herein,2D/2D WSe_(2)/ZnIn_(2)S_(4) heterostructures with strong hetero-interface interaction and abundant contact were constructed via an impregnation-annealing strategy.Efficient charge transfer from ZnIn_(2)S_(4) to WSe_(2)was evidenced by transient absorption spectroscopy in crafted heterostructures owing to the tight and2D face-to-face contact.As a result,the prepared WSe_(2)/ZnIn_(2)S_(4) heterostructures exhibited boosted photocatalytic performance and a highest hydrogen evolution rate of 3.377 mmol/(g h)was achieved with an apparent quantum yield of 45.7%at 420 nm.The work not only provides new strategies to achieve efficient 2D/2D heterostructures but also paves the way for the development of green hydrogen in the future.展开更多
Background: With the development of high quality nursing service, hospitals put forward higher requirements for nurses’ service level. In recent years, the number and quality of specialized nurses remain to be improv...Background: With the development of high quality nursing service, hospitals put forward higher requirements for nurses’ service level. In recent years, the number and quality of specialized nurses remain to be improved despite the remarkable achievements in the construction of specialized nurses. Objective: This study intended to explore a standardized training mode for nurses oriented by training and assessment of nursespecialty knowledge and to summarize the practical experience of this mode. Methods: The training and assessment program was formulated by starting from the objectives of training clinical front-line nursing staff in our hospital, and the standard training and assessment were carried out from four aspects: the specialized disease knowledge, the condition observation and reporting ability, emergency and severe disease nursing, and perioperative accelerated rehabilitation guidance. These four items are hereinafter referred to as “Four Passes” training and assessment, and it was practiced in the assessment and training of nurses in our hospital from 2020 to 2022. Results: A total of 915 front-line caregivers were surveyed in our study, including 772 nurses and 143 doctors. After two years of implementation, the self-evaluation of nurses increased from (2.96 ± 0.79) points to (3.64 ± 0.78) points, and the evaluation score by doctors increased from (3.94 ± 0.74) points to (4.26 ± 0.72) points. The core competence of specialty increased from (69.22 ± 16.53) points to (85.42 ± 14.44) points. The scores of all dimensions after training were higher than those before training, with statistical significances. Conclusion: The “Four Passes” training and assessment of nurse specialty knowledge can fully mobilize the enthusiasm of managers and nurses in all departments, ensure solid specialty knowledge, improve nurses’ core competence, improve nursing quality, and create a harmonious relationship between nurses and patients as well as between doctors and patients.展开更多
Fruit colour is essential to seed dispersal,speciation,and biological diversity in global ecosystems.The relationship between fruit-colour variation and species diversification has long been of interest in evolutionar...Fruit colour is essential to seed dispersal,speciation,and biological diversity in global ecosystems.The relationship between fruit-colour variation and species diversification has long been of interest in evolutionary biology,but remains poorly understood at the genus level.Here,we used Callicarpa,a typical representative of pantropical angiosperm,to analyse whether fruit colours are correlated with biogeographic distribution,dispersal events,and diversification rate.We estimated a time-calibrated phylogeny for Callicarpa and reconstructed ancestral fruit colour.Utilizing phylogenetic methods,we estimated the major dispersal events across the phylogenetic tree and the most likely fruit colours related to each dispersal event,and tested whether the dispersal frequencies and distances of the four fruit colours between major biogeographical areas were equal.We then tested whether fruit colours are correlated with latitude,elevation,and diversification rate.Biogeographical reconstructions showed that Callicarpa originated in the East Asia and Southeast Asia during the Eocene(-35.53 Ma) and diverse species diverged mainly in the Miocene and lasted into the Pleistocene.Large-scale dispersal events were significantly associated with violet-fruited lineages.Furthermore,different fruit colours were markedly correlated with different latitudes and elevations(e.g.,violet fruits were correlated with higher latitudes and elevations;red fruits and black fruits with lower latitudes;white fruits with higher elevations).Notably,violet fruits were statistically associated with highest diversification rates,driving fruit colour variation among different regions globally.Our results contribute to further understanding why fruit colour is so variable at the genus level of angiosperms in different areas around the world.展开更多
Optical enhancement cavity(OEC)is a powerful tool for fundamental research and diagnostics.In this paper,the progress of a continuous-wave OEC to realize of megawatt cavity for a novel light source based on a steady-s...Optical enhancement cavity(OEC)is a powerful tool for fundamental research and diagnostics.In this paper,the progress of a continuous-wave OEC to realize of megawatt cavity for a novel light source based on a steady-state microbunching(SSMB)mechanism,is reported.After efficiently suppressing all external noise and optimizing the alignment,mode-matching,and polarization matching,stable and long-term locking is achieved with the help of two feedback loops.The modal instability phenomenon caused by the surface thermoelastic deformation is observed.A pair of D-shape mirrors are utilized to remove the high-order modes.Finally,an intra-cavity average power of 30 kW is reached.展开更多
Background:Busulfan(BU)is an alkylating agent used as a conditioning agent prior to hematopoietic stem cell(HSC)transplantation as it is known to be cytotoxic to host hematopoietic stem and progenitor cells.The suscep...Background:Busulfan(BU)is an alkylating agent used as a conditioning agent prior to hematopoietic stem cell(HSC)transplantation as it is known to be cytotoxic to host hematopoietic stem and progenitor cells.The susceptibility of HSCs to BU injury plays an important role in the myeloablative efficacy of BU.Different susceptibilities were demonstrated in genetically diverse(GD)mice in our preliminary research.Methods:Three strains of GD mice with different susceptibilities to BU-i nduced HSC injury were used for screening biological markers of HSC injury susceptibility in urine.The urine proteins were analyzed using liquid chromatography coupled with tandem mass spectrometry to screen for differentially expressed proteins.Screening for possible biomarkers based on differences in protein expression abundance was validated using enzyme-l inked immunoassay(ELISA).Results:Functional analysis showed that the differential proteins were all involved in a series of biological pathways related to cellular senescence,apoptosis,and angiogenesis;whereas the differential proteins of the high-susceptible strain were enriched for the regulation of bone marrow microenvironment pathways,those of low-susceptible strain were enriched for the proapoptotic effect of GTPase pathways.Based on protein abundance differences,several urinary proteins that may be indicative of susceptibility were screened,and ELISA validation results showed that angiotensin-converting enzyme may be a potential biomarker predicting HSC susceptibility for BU conditioning.Conclusions:This study indicates that urinary protein levels can reflect differences in susceptibility to BU-i nduced HSC injury.Using GD mice to construct genetic difference models will provide preclinical data for screening BU-related biological markers.展开更多
Foam drainage is theflow of liquid through the interstitial spaces between bubbles driven by capillarity and grav-ity and resisted by viscous damping.The so-called foam drainage gas recovery technology is a technique ...Foam drainage is theflow of liquid through the interstitial spaces between bubbles driven by capillarity and grav-ity and resisted by viscous damping.The so-called foam drainage gas recovery technology is a technique tradi-tionally used to mitigate the serious bottom-hole liquid loading in the middle and late stages of gas well production.In this context,determining the optimal concentration of the bubble drainage agent is generally cru-cial for the proper application of this method.In this study,a combination of indoor experiments and theoretical analysis have been used to determine the pressure drop related to the foam-carrying capacity in a representative gasfield.Dynamic and static experiments were designed with a bubble drainage agent concentration varying in the range 0.3%–0.6%.Using thefield formation water data,the optimal soaking agent concentration was obtained and pressure drop test experiments on the foam carrying capacity were conducted accordingly.These tests have revealed that the optimal foam displacement agent concentration is 0.5%,and the foam quality at the optimum concentration is between 0.78–0.98.A theoretical method for calculating the pressure drop at the optimum soak-away concentration based on experimental data has also been introduced.The error of the proposed method is within 15%compared to the experimental measured value,demonstrating that it is highly accurate and simple.展开更多
DEAR EDITOR,Despite the generally increased cancer risk in large,long-lived organisms,cetaceans,among the largest and longest-living mammals,appear to possess a counteracting mechanism.Nevertheless,the genetic basis u...DEAR EDITOR,Despite the generally increased cancer risk in large,long-lived organisms,cetaceans,among the largest and longest-living mammals,appear to possess a counteracting mechanism.Nevertheless,the genetic basis underlying this mechanism remains poorly understood.The p53 pathway serves as an ideal target for studying the mechanisms behind cancer resistance,as most cancer types have evolved strategies to circumvent its suppressive functions.展开更多
In the published version of Figure 21,an error appeared in Figure 2C on page 1468.In Figure 2C,the Kaplan-Meier estimation of the overall survival of patients with recurrent DG classified according to molecular subtyp...In the published version of Figure 21,an error appeared in Figure 2C on page 1468.In Figure 2C,the Kaplan-Meier estimation of the overall survival of patients with recurrent DG classified according to molecular subtypes was mistakenly covered by the curves of patients with primary DGs during the figure layout process,while the number statistic under the figure is correct.Figure 2C has been updated to correct this mistake.The error does not affect the conclusions of this article.We apologize for the error and for any confusion that it might have caused.展开更多
We establish a model for a four-terminal thermoelectric system,based on three coupled quantum dots,which consists of a left/right electron reservoir(the source and the drain),two thermal reservoirs and three coupled q...We establish a model for a four-terminal thermoelectric system,based on three coupled quantum dots,which consists of a left/right electron reservoir(the source and the drain),two thermal reservoirs and three coupled quantum dots.Based on the master equation theory,we derive the expressions of the electron current and heat flow among the three quantum dots and the corresponding reservoir.We show that the source can be cooled by passing a thermal current between the two thermal reservoirs,with no net heat exchange between the thermal reservoirs and the electron reservoirs.This effect is called the Coulomb heat drag effect.Then,we define the coefficient of performance(COP) and the cooling power.The influence of the main system parameters,such as charging energy,energy level,and temperature,on the performance of the four-terminal thermoelectric system is analyzed in detail.By choosing appropriate parameters one can obtain the maximum cooling power and the corresponding COP.Finally,we also show that the Maxwell demon effect can be realized by using nonequilibrium thermal reservoirs in our four-terminal thermoelectric system.展开更多
A 3-year-old boy presented with bluish patch and scattered blue spots on the left side of his face.After several sessions of laser treatment,the azury patch in the periorbital area became even darker.Histopathology sh...A 3-year-old boy presented with bluish patch and scattered blue spots on the left side of his face.After several sessions of laser treatment,the azury patch in the periorbital area became even darker.Histopathology showed many bipolar,pigment-laden dendritic cells scattered in the papillary and upper reticular dermis.Immunohistochemically,these cells were positive for S100,SOX-10,melan-A,P16,and HMB-45.The positive rate of Ki-67 was less than 5%.Finally,the lesion was diagnosed with nevus of Ota concurrent with common blue nevus.Therefore,for cases of the nevus of Ota with poor response to laser treatment,the possible coexisting diseases should be suspected.展开更多
OBJECTIVES To investigate the value of CCKBR^(fl/fl)villin-Cre mice as a mouse model of salt-sensitive hypertension(SSH).METHODS In the first part,2-month-old CCKBR^(fl/fl)villin-Cre mice(CKO)and control CCKBR^(fl/fl)...OBJECTIVES To investigate the value of CCKBR^(fl/fl)villin-Cre mice as a mouse model of salt-sensitive hypertension(SSH).METHODS In the first part,2-month-old CCKBR^(fl/fl)villin-Cre mice(CKO)and control CCKBR^(fl/fl)mice(WT)were fed with normal diet(0.4%NaCl)or high salt diet(4%NaCl),separately for 6 weeks.In the rescue study,one week of hydrochlorothiazide or saline injection were treated with the CKO mice fed high salt diet.The blood pressure,biochemical indexes,and the expression of small intestinal sodium transporters(NHE3,NKCC1,eNaC)was detected.The organ injury markers(MMP2/MMP9)and the histopathological changes of kidneys were observed,whereas the changes of duodenal sodium absorption were detected by small intestinal perfusion in vivo.RESULTS The CCKBR^(fl/fl)villin-Cre mice with high salt intake exhibited high blood pressure,increased duodenal sodium absorption and urinary sodium excretion,and with renal injury.The protein expression of NHE3,NKCC1 and eNaC were also significant increase in the intestine of CKO-HS mice.Treatment with hydrochlorothiazide remarkably attenuated the elevated blood pressure by high salt absorption in the CCKBR^(fl/fl)villin-Cre mice,but no significant histopathological changes were observed.CONCLUSIONS These results support a crucial role of intestinal Cckbr deficiency on SSH development and the diuretic antihypertension effect in CCKBR^(fl/fl)villin-Cre mice.The CCKBR^(fl/fl)villin-Cre mice with the high salt intake may serve as a stable model of salt-sensitive hypertensive induced by sodium overloading.展开更多
INTRODUCTION Addiction is a major global risk factor for disability and premature death'and has become a public health and social problem worldwide.Despite substantial investments from governments and research ins...INTRODUCTION Addiction is a major global risk factor for disability and premature death'and has become a public health and social problem worldwide.Despite substantial investments from governments and research institutionsglobally,current addictionmedicine research remains centred in Western countries.However,theories,models and results from western-centric research may not be applicable to different cultures.Non-Western countries such as China and Iran,and Western countries are committed to establishing addiction prevention and treatment tailored to their unique histories and cultures.To foster a global addiction science,it is important to increase the diversity of evidence without preconceived biases.展开更多
At present,water pollution has become an important factor affecting and restricting national and regional economic development.Total phosphorus is one of the main sources of water pollution and eutrophication,so the p...At present,water pollution has become an important factor affecting and restricting national and regional economic development.Total phosphorus is one of the main sources of water pollution and eutrophication,so the prediction of total phosphorus in water quality has good research significance.This paper selects the total phosphorus and turbidity data for analysis by crawling the data of the water quality monitoring platform.By constructing the attribute object mapping relationship,the correlation between the two indicators was analyzed and used to predict the future data.Firstly,the monthly mean and daily mean concentrations of total phosphorus and turbidity outliers were calculated after cleaning,and the correlation between them was analyzed.Secondly,the correlation coefficients of different times and frequencies were used to predict the values for the next five days,and the data trend was predicted by python visualization.Finally,the real value was compared with the predicted value data,and the results showed that the correlation between total phosphorus and turbidity was useful in predicting the water quality.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.32101489)Forestry Science and Technology Innovation Program of Hunan Province(Grant No.XLK202101-2)Science and Technology Innovation Platform and Talent Program of Hunan Province(Grant Nos.2023RC3164,2021NK1007)。
文摘Unreduced gametes through chromosome doubling play a major role in the process of plant polyploidization.Our previous work confirmed that Camellia oleifera can produce natural 2n pollen,and it is possible to induce the 2n pollen formation by high temperature treatment.This study focused on the optimization of the 2n pollen induction technique and the mechanisms of high temperature-induced2n pollen formation in C.oleifera.We found that the optimal protocol for inducing 2n pollen via high temperature was to perform 45℃with4 h at the prophaseⅠstage of the pollen mother cells(PMCs).Meanwhile,high temperature significantly decreased the yield and fertility of2n pollen.Through the observation of meiosis,abnormal chromosome and cytological behaviour was discovered under high-temperature treatment,and we confirmed that the formation of 2n pollen is caused by abnormal cell plate.Based on weighted gene co-expression network analysis,fifteen hub genes related to cell cycle control were identified.After male flower buds were exposed to heat shock,polygalacturonase gene(CoPGX3)was significantly upregulated.We inferred that high temperature causes the CoPGX3 gene to be overexpressed and that CoPGX3 is redistributed into the cytosol where it degrades cytoplasmic pectin,which leads to an abnormal cell plate.Furthermore,abnormal cytokinesis resulted in the formation of dyads and triads,and PMCs divided to produce 2n pollen.Our findings provide new insights into the mechanism of 2n pollen induced by high temperature in a woody plant and lay a foundation for further ploidy breeding of C.oleifera.
基金Project supported by National Key Research and Development Program of China (Grant No.2022YFA1603403)。
文摘Finesse is a critical parameter for describing the characteristics of an optical enhancement cavity(OEC). This paper first presents a review of finesse measurement techniques, including a comparative analysis of the advantages, disadvantages, and potential limitations of several main methods from both theoretical and practical perspectives. A variant of the existing method called the free spectral range(FSR) modulation method is proposed and compared with three other finesse measurement methods, i.e., the fast-switching cavity ring-down(CRD) method, the rapidly swept-frequency(SF) CRD method, and the ringing effect method. A high-power OEC platform with a high finesse of approximately 16000 is built and measured with the four methods. The performance of these methods is compared, and the results show that the FSR modulation method and the fast-switching CRD method are more suitable and accurate than the other two methods for high-finesse OEC measurements. The CRD method and the ringing effect method can be implemented in open loop using simple equipment and are easy to perform. Additionally, recommendations for selecting finesse measurement methods under different conditions are proposed, which benefit the development of OEC and its applications.
基金National Natural Science Foundation of China (No. 51605384)the Natural Science Foundation of Gansu Province,China (No. 21JR7RA308)。
文摘A three-dimensional, two-temperature(2T) model of a lamellar cathode arc is constructed,drawing upon the conservation equations for mass, momentum, electron energy, and heavy particle energy, in addition to Maxwell's equations. The model aims to elucidate how the physical properties of electrons and heavy particles affect heat transfer and fluid flow in a lamellar cathode arc. This is achieved by solving and comparing the fields of electron temperature,heavy particle temperature, fluid flow, current density, and Lorentz force distribution under varying welding currents. The results show that the guiding effect of the lamellar cathode on current density, the inertial drag effect of moving arc, and the attraction effect of Lorentz force at the lamellar cathode tip primarily govern the distribution of the arc's physical fields. The guiding effect localizes the current density to the front end of the lamellar cathode, particularly where the discharge gap is minimal. Both the inertial drag effect and the attraction effect of Lorentz force direct arc flow toward its periphery. Under the influence of the aforementioned factors, the physical fields of the lamellar cathode arc undergo expansion and shift counter to the arc's direction of motion. A reduction in welding current substantially weakens the guiding effect,causing the arc's physical fields to deviate further in the direction opposite to the arc motion. In comparison with a cylindrical cathode arc, the physical fields of the lamellar cathode arc are markedly expanded, leading to a reduction in current density, electron temperature, heavy particle temperature, cathode jet flow velocity, and Lorentz force.
基金supported by the Key Project of Tianjin Natural Science Foundation (No.21JCZDJC01080)the Tianjin Key Medical Discipline (Specialty) (TJYXZDX K-029A)+1 种基金the Academic Backbone of “Clinical Talent Training and Climbing Plan” of Tianjin Medical University and the Tianjin Health Research ProjectScience and Technology Development Fund of Nanjing Medical University (NMUB20210180)。
文摘BACKGROUND Chronic renal failure(CRF) patients are predisposed to arrhythmias, while the detailed mechanisms are unclear. We hypothesized the chronic inflammatory state of CRF patients may lead to cardiac sympathetic remodeling, increasing the incidence of ventricular arrhythmia(VA) and sudden cardiac death. And explored the role of atorvastatin and etanercept in this process.METHODS A total of 48 rats were randomly divided into sham operation group(Sham group), CRF group, CRF + atorvastatin group(CRF + statin group), and CRF + etanercept group(CRF + rhTNFR-Fcgroup). Sympathetic nerve remodeling was assessed by immunofluorescence of growth-associated protein 43(GAP-43) and tyrosine hydroxylase positive area fraction. Electrophysiological testing was performed to assess the incidence of VA by assessing the ventricular effective refractory period and ventricular fibrillation threshold. The levels of tumor necrosis factor-alpha(TNF-α) and interleukin-1beta were determined by Western blotting and enzyme-linked immunosorbent assay.RESULTS Echocardiogram showed that compared with the Sham group, left ventricular end-systolic diameter and ventricular weight/body weight ratio were significantly higher in the CRF group. Hematoxylin-eosin and Masson staining indicated that myocardial fibers were broken, disordered, and fibrotic in the CRF group. Western blotting, enzyme-linked immunosorbent assay,immunofluorescence and electrophysiological examination suggested that compared with the Sham group, GAP-43 and TNF-α proteins were significantly upregulated, GAP-43 and tyrosine hydroxylase positive nerve fiber area was increased, and ventricular fibrillation threshold was significantly decreased in the CRF group. The above effects were inhibited in the CRF + statin group and the CRF + rhTNFR-Fcgroup.CONCLUSIONS In CRF rats, TNF-α was upregulated, cardiac sympathetic remodeling was more severe, and the nephrogenic cardiac sympathetic remodeling existed. Atorvastatin and etanercept could downregulate the expression of TNF-α or inhibit its activity, thus inhibited the above effects, and reduced the occurrence of VA and sudden cardiac death.
基金financially supported by the National Natural Science Foundation of China (No.52106259)the Fundamental Research Funds for the Central Universities (2024MS013)Key Research and Development Program of Shaanxi (Program No.2022LL-JB-08)。
文摘Green hydrogen is urgently required for sustainable development of human beings and rational construction of heterostructures holds great promising for photocatalytic hydrogen generation.Herein,2D/2D WSe_(2)/ZnIn_(2)S_(4) heterostructures with strong hetero-interface interaction and abundant contact were constructed via an impregnation-annealing strategy.Efficient charge transfer from ZnIn_(2)S_(4) to WSe_(2)was evidenced by transient absorption spectroscopy in crafted heterostructures owing to the tight and2D face-to-face contact.As a result,the prepared WSe_(2)/ZnIn_(2)S_(4) heterostructures exhibited boosted photocatalytic performance and a highest hydrogen evolution rate of 3.377 mmol/(g h)was achieved with an apparent quantum yield of 45.7%at 420 nm.The work not only provides new strategies to achieve efficient 2D/2D heterostructures but also paves the way for the development of green hydrogen in the future.
文摘Background: With the development of high quality nursing service, hospitals put forward higher requirements for nurses’ service level. In recent years, the number and quality of specialized nurses remain to be improved despite the remarkable achievements in the construction of specialized nurses. Objective: This study intended to explore a standardized training mode for nurses oriented by training and assessment of nursespecialty knowledge and to summarize the practical experience of this mode. Methods: The training and assessment program was formulated by starting from the objectives of training clinical front-line nursing staff in our hospital, and the standard training and assessment were carried out from four aspects: the specialized disease knowledge, the condition observation and reporting ability, emergency and severe disease nursing, and perioperative accelerated rehabilitation guidance. These four items are hereinafter referred to as “Four Passes” training and assessment, and it was practiced in the assessment and training of nurses in our hospital from 2020 to 2022. Results: A total of 915 front-line caregivers were surveyed in our study, including 772 nurses and 143 doctors. After two years of implementation, the self-evaluation of nurses increased from (2.96 ± 0.79) points to (3.64 ± 0.78) points, and the evaluation score by doctors increased from (3.94 ± 0.74) points to (4.26 ± 0.72) points. The core competence of specialty increased from (69.22 ± 16.53) points to (85.42 ± 14.44) points. The scores of all dimensions after training were higher than those before training, with statistical significances. Conclusion: The “Four Passes” training and assessment of nurse specialty knowledge can fully mobilize the enthusiasm of managers and nurses in all departments, ensure solid specialty knowledge, improve nurses’ core competence, improve nursing quality, and create a harmonious relationship between nurses and patients as well as between doctors and patients.
基金funded by National Natural Science Foundation of China under Grant [31760045 and 31970220]Natural Science Foundation of Guangxi Province under Grant[2018GXNSFAA281132]。
文摘Fruit colour is essential to seed dispersal,speciation,and biological diversity in global ecosystems.The relationship between fruit-colour variation and species diversification has long been of interest in evolutionary biology,but remains poorly understood at the genus level.Here,we used Callicarpa,a typical representative of pantropical angiosperm,to analyse whether fruit colours are correlated with biogeographic distribution,dispersal events,and diversification rate.We estimated a time-calibrated phylogeny for Callicarpa and reconstructed ancestral fruit colour.Utilizing phylogenetic methods,we estimated the major dispersal events across the phylogenetic tree and the most likely fruit colours related to each dispersal event,and tested whether the dispersal frequencies and distances of the four fruit colours between major biogeographical areas were equal.We then tested whether fruit colours are correlated with latitude,elevation,and diversification rate.Biogeographical reconstructions showed that Callicarpa originated in the East Asia and Southeast Asia during the Eocene(-35.53 Ma) and diverse species diverged mainly in the Miocene and lasted into the Pleistocene.Large-scale dispersal events were significantly associated with violet-fruited lineages.Furthermore,different fruit colours were markedly correlated with different latitudes and elevations(e.g.,violet fruits were correlated with higher latitudes and elevations;red fruits and black fruits with lower latitudes;white fruits with higher elevations).Notably,violet fruits were statistically associated with highest diversification rates,driving fruit colour variation among different regions globally.Our results contribute to further understanding why fruit colour is so variable at the genus level of angiosperms in different areas around the world.
基金the Fund from Tsinghua University Initiative Scientific Research Program,China(Grant No.20191081195).
文摘Optical enhancement cavity(OEC)is a powerful tool for fundamental research and diagnostics.In this paper,the progress of a continuous-wave OEC to realize of megawatt cavity for a novel light source based on a steady-state microbunching(SSMB)mechanism,is reported.After efficiently suppressing all external noise and optimizing the alignment,mode-matching,and polarization matching,stable and long-term locking is achieved with the help of two feedback loops.The modal instability phenomenon caused by the surface thermoelastic deformation is observed.A pair of D-shape mirrors are utilized to remove the high-order modes.Finally,an intra-cavity average power of 30 kW is reached.
基金National Natural Scientific Foundation of ChinaGrant/Award Number:81972975+2 种基金National Human Diseases Animal Model Resource CenterNational Science Foundation for Young Scientists of ChinaGrant/Award Number:81703170。
文摘Background:Busulfan(BU)is an alkylating agent used as a conditioning agent prior to hematopoietic stem cell(HSC)transplantation as it is known to be cytotoxic to host hematopoietic stem and progenitor cells.The susceptibility of HSCs to BU injury plays an important role in the myeloablative efficacy of BU.Different susceptibilities were demonstrated in genetically diverse(GD)mice in our preliminary research.Methods:Three strains of GD mice with different susceptibilities to BU-i nduced HSC injury were used for screening biological markers of HSC injury susceptibility in urine.The urine proteins were analyzed using liquid chromatography coupled with tandem mass spectrometry to screen for differentially expressed proteins.Screening for possible biomarkers based on differences in protein expression abundance was validated using enzyme-l inked immunoassay(ELISA).Results:Functional analysis showed that the differential proteins were all involved in a series of biological pathways related to cellular senescence,apoptosis,and angiogenesis;whereas the differential proteins of the high-susceptible strain were enriched for the regulation of bone marrow microenvironment pathways,those of low-susceptible strain were enriched for the proapoptotic effect of GTPase pathways.Based on protein abundance differences,several urinary proteins that may be indicative of susceptibility were screened,and ELISA validation results showed that angiotensin-converting enzyme may be a potential biomarker predicting HSC susceptibility for BU conditioning.Conclusions:This study indicates that urinary protein levels can reflect differences in susceptibility to BU-i nduced HSC injury.Using GD mice to construct genetic difference models will provide preclinical data for screening BU-related biological markers.
基金support provided by the National Natural Science Foundation of China(No.62173049)the Open Fund of the Key Laboratory of Exploration Technologies for Oil and Gas Resources(Yangtze University),Ministry of Education(Grant K2021-17).
文摘Foam drainage is theflow of liquid through the interstitial spaces between bubbles driven by capillarity and grav-ity and resisted by viscous damping.The so-called foam drainage gas recovery technology is a technique tradi-tionally used to mitigate the serious bottom-hole liquid loading in the middle and late stages of gas well production.In this context,determining the optimal concentration of the bubble drainage agent is generally cru-cial for the proper application of this method.In this study,a combination of indoor experiments and theoretical analysis have been used to determine the pressure drop related to the foam-carrying capacity in a representative gasfield.Dynamic and static experiments were designed with a bubble drainage agent concentration varying in the range 0.3%–0.6%.Using thefield formation water data,the optimal soaking agent concentration was obtained and pressure drop test experiments on the foam carrying capacity were conducted accordingly.These tests have revealed that the optimal foam displacement agent concentration is 0.5%,and the foam quality at the optimum concentration is between 0.78–0.98.A theoretical method for calculating the pressure drop at the optimum soak-away concentration based on experimental data has also been introduced.The error of the proposed method is within 15%compared to the experimental measured value,demonstrating that it is highly accurate and simple.
基金supported by the National Key Program of Research and Development,Ministry of Science and Technology of China (2022YFF1301600)National Natural Science Foundation of China (32070409,32270453 to S.X.X.)+1 种基金Priority Academic Program Development of Jiangsu Higher Education Institutions to G.Y.and S.X.X.Qing Lan Project of Jiangsu Province to S.X.X.
文摘DEAR EDITOR,Despite the generally increased cancer risk in large,long-lived organisms,cetaceans,among the largest and longest-living mammals,appear to possess a counteracting mechanism.Nevertheless,the genetic basis underlying this mechanism remains poorly understood.The p53 pathway serves as an ideal target for studying the mechanisms behind cancer resistance,as most cancer types have evolved strategies to circumvent its suppressive functions.
文摘In the published version of Figure 21,an error appeared in Figure 2C on page 1468.In Figure 2C,the Kaplan-Meier estimation of the overall survival of patients with recurrent DG classified according to molecular subtypes was mistakenly covered by the curves of patients with primary DGs during the figure layout process,while the number statistic under the figure is correct.Figure 2C has been updated to correct this mistake.The error does not affect the conclusions of this article.We apologize for the error and for any confusion that it might have caused.
基金supported by the National Natural Science Foundation of China(Grant No.11875034)。
文摘We establish a model for a four-terminal thermoelectric system,based on three coupled quantum dots,which consists of a left/right electron reservoir(the source and the drain),two thermal reservoirs and three coupled quantum dots.Based on the master equation theory,we derive the expressions of the electron current and heat flow among the three quantum dots and the corresponding reservoir.We show that the source can be cooled by passing a thermal current between the two thermal reservoirs,with no net heat exchange between the thermal reservoirs and the electron reservoirs.This effect is called the Coulomb heat drag effect.Then,we define the coefficient of performance(COP) and the cooling power.The influence of the main system parameters,such as charging energy,energy level,and temperature,on the performance of the four-terminal thermoelectric system is analyzed in detail.By choosing appropriate parameters one can obtain the maximum cooling power and the corresponding COP.Finally,we also show that the Maxwell demon effect can be realized by using nonequilibrium thermal reservoirs in our four-terminal thermoelectric system.
基金This study was funded by the CAMS Innovation Fund for Medical Sciences(CIFMS-2021-I2M-1-001)National Natural Science Foundation of China(82103705).
文摘A 3-year-old boy presented with bluish patch and scattered blue spots on the left side of his face.After several sessions of laser treatment,the azury patch in the periorbital area became even darker.Histopathology showed many bipolar,pigment-laden dendritic cells scattered in the papillary and upper reticular dermis.Immunohistochemically,these cells were positive for S100,SOX-10,melan-A,P16,and HMB-45.The positive rate of Ki-67 was less than 5%.Finally,the lesion was diagnosed with nevus of Ota concurrent with common blue nevus.Therefore,for cases of the nevus of Ota with poor response to laser treatment,the possible coexisting diseases should be suspected.
基金This study is funded by the CAMS Innovation Fund for Medical Sciences(CIFMS,2022-I2M-C&T-A-010)the National Natural Science Foundation(China)(81970358).
文摘OBJECTIVES To investigate the value of CCKBR^(fl/fl)villin-Cre mice as a mouse model of salt-sensitive hypertension(SSH).METHODS In the first part,2-month-old CCKBR^(fl/fl)villin-Cre mice(CKO)and control CCKBR^(fl/fl)mice(WT)were fed with normal diet(0.4%NaCl)or high salt diet(4%NaCl),separately for 6 weeks.In the rescue study,one week of hydrochlorothiazide or saline injection were treated with the CKO mice fed high salt diet.The blood pressure,biochemical indexes,and the expression of small intestinal sodium transporters(NHE3,NKCC1,eNaC)was detected.The organ injury markers(MMP2/MMP9)and the histopathological changes of kidneys were observed,whereas the changes of duodenal sodium absorption were detected by small intestinal perfusion in vivo.RESULTS The CCKBR^(fl/fl)villin-Cre mice with high salt intake exhibited high blood pressure,increased duodenal sodium absorption and urinary sodium excretion,and with renal injury.The protein expression of NHE3,NKCC1 and eNaC were also significant increase in the intestine of CKO-HS mice.Treatment with hydrochlorothiazide remarkably attenuated the elevated blood pressure by high salt absorption in the CCKBR^(fl/fl)villin-Cre mice,but no significant histopathological changes were observed.CONCLUSIONS These results support a crucial role of intestinal Cckbr deficiency on SSH development and the diuretic antihypertension effect in CCKBR^(fl/fl)villin-Cre mice.The CCKBR^(fl/fl)villin-Cre mice with the high salt intake may serve as a stable model of salt-sensitive hypertensive induced by sodium overloading.
文摘INTRODUCTION Addiction is a major global risk factor for disability and premature death'and has become a public health and social problem worldwide.Despite substantial investments from governments and research institutionsglobally,current addictionmedicine research remains centred in Western countries.However,theories,models and results from western-centric research may not be applicable to different cultures.Non-Western countries such as China and Iran,and Western countries are committed to establishing addiction prevention and treatment tailored to their unique histories and cultures.To foster a global addiction science,it is important to increase the diversity of evidence without preconceived biases.
基金the National Natural Science Foundation of China(No.51775185)Natural Science Foundation of Hunan Province(No.2022JJ90013)+1 种基金Intelligent Environmental Monitoring Technology Hunan Provincial Joint Training Base for Graduate Students in the Integration of Industry and Education,and Hunan Normal University University-Industry Cooperation.the 2011 Collaborative Innovation Center for Development and Utilization of Finance and Economics Big Data Property,Universities of Hunan Province,Open Project,Grant Number 20181901CRP04.
文摘At present,water pollution has become an important factor affecting and restricting national and regional economic development.Total phosphorus is one of the main sources of water pollution and eutrophication,so the prediction of total phosphorus in water quality has good research significance.This paper selects the total phosphorus and turbidity data for analysis by crawling the data of the water quality monitoring platform.By constructing the attribute object mapping relationship,the correlation between the two indicators was analyzed and used to predict the future data.Firstly,the monthly mean and daily mean concentrations of total phosphorus and turbidity outliers were calculated after cleaning,and the correlation between them was analyzed.Secondly,the correlation coefficients of different times and frequencies were used to predict the values for the next five days,and the data trend was predicted by python visualization.Finally,the real value was compared with the predicted value data,and the results showed that the correlation between total phosphorus and turbidity was useful in predicting the water quality.