Quantitative real-time PCR(qPCR)is widely used for gene expression analysis,but its accuracy critically depends on stable internal reference genes for normalization.In marine invertebrates,especially non-model taxa su...Quantitative real-time PCR(qPCR)is widely used for gene expression analysis,but its accuracy critically depends on stable internal reference genes for normalization.In marine invertebrates,especially non-model taxa such as cephalopods,systematic evaluation of reference genes is limited,leading to potential bias.The cuttlefish Sepiella japonica is ecologically and economically important in China,yet previous molecular studies have often relied on single unvalidated reference genes,which may compromise data reliability.This study aimed to systematically evaluate the stability of five commonly used reference genes(18S,ef-1α,ef-1γ,gapdh,andβ-actin)across multiple tissues and sexes of S.japonica,and to identify the most suitable reference genes and optimal number for qPCR normalization.Fifteen to sixteen tissue types were collected from ten healthy adults(five males and five females).Total RNA was extracted,reverse-transcribed,and analyzed by qPCR.Gene stability was assessed using four algorithms(geNorm,NormFinder,BestKeeper,andΔCt)integrated with RefFinder,and the optimal gene number was determined using geNorm pairwise variation(V_(n/n+1)<0.15).Four transcriptome-derived genes(creld2,cd109,acy1,and miox)were used for validation.The C_(t)values of the five genes ranged from 15.47 to 20.83.β-actin and gapdh showed pronounced variability in expression stability among tissues and sexes,indicating their limited suitability for normalization.18S exhibited the highest expression(mean C_(t):15.47-16.29)and lowest variability but displayed sex-biased expression,whereas ef-1αand ef-1γremained consistently stable across most tissues in both sexes,with ef-1αbeing the most robust and showing no sex-related bias.Although specific rankings varied among tissues and sexes,the comprehensive results indicated that ef-1αand ef-1γpossessed the highest overall stability,followed by 18S,whileβ-actin and gapdh were the least stable.The final comprehensive rankings were ef-1γ>ef-1α>18S>gapdh>β-actin(male)and ef-1α>ef-1γ>18S>gapdh>β-actin(female).geNorm analysis(V2/3<0.15)indicated that two genes,mainly ef-1αand ef-1γ,were generally sufficient for reliable normalization in most tissues.Validation confirmed that normalization using the stable ef-1αand ef-1γaccurately reflected the expression differences among tissues,whereasβ-actin and gapdh can bias or confound statistical analyses.ef-1αand ef-1γare identified as the most reliable reference gene combination for qPCR analysis in S.japonica,while 18S can serve as an auxiliary gene for within-sex comparisons.The use ofβ-actin or gapdh alone is not recommended.This study establishes a systematic framework for selecting reliable reference genes in S.japonica,thereby facilitating robust qPCR normalization and providing a foundation for future gene expression research in S.japonica and other cephalopods.展开更多
Objectives:Ribosomal protein S6 kinase A2(RPS6KA2)has been identified as a potential prognostic biomarker in several cancers,including breast cancer,glioblastoma,and prostate cancer.However,its functional significance...Objectives:Ribosomal protein S6 kinase A2(RPS6KA2)has been identified as a potential prognostic biomarker in several cancers,including breast cancer,glioblastoma,and prostate cancer.However,its functional significance in ovarian cancer is not well characterized.This study was designed to explore the therapeutic relevance of modulating RPS6KA2 in the context of ovarian cancer,particularly in relation to cisplatin resistance.Methods:The expression levels of RPS6KA2 and key regulators involved in autophagy and ferroptosis were assessed using quantitative reverse transcription-PCR,immunofluorescence staining,immunohistochemistry,and western blotting.Prognostic associations were conducted using the Kaplan-Meier Plotter database.Autophagy flux assays and visualization of autophagosomes were performed to assess autophagy activity.Ferroptosis-related parameters,including intracellular iron content,glutathione(GSH)levels,reactive oxygen species(ROS)generation,and mitochondrial membrane potential,were measured to determine ferroptotic changes.In vivo experiments were carried out to determine the antitumor efficacy of RPS6KA2 modulation in combination with pathway-specific agents.Results:Using ovarian cancer cell lines and clinical tissue samples,we demonstrated that RPS6KA2 expression was significantly downregulated in cisplatin-resistant cells and tissues compared to their sensitive counterparts.Low RPS6KA2 expression correlated with unfavorable patient outcomes and enhanced chemoresistance.Mechanistically,RPS6KA2 inhibited autophagy by modulating the phosphatidylinositol 3-kinase-protein kinase B-mammalian target of rapamycin(PI3K-AKT-mTOR)signaling pathway,which in turn increased sensitivity to cisplatin.Additionally,RPS6KA2 facilitated ferroptosis,contributing to its tumor-suppressive function.miR-512-3p was identified as a negative regulator of RPS6KA2,driving cisplatin resistance through suppression of RPS6KA2 expression.In vivo validation confirmed that combining RPS6KA2 targeting with autophagy inhibitors or ferroptosis inducers significantly enhanced cisplatin sensitivity in ovarian cancer models.Conclusion:These results collectively indicate that targeting the miR-512-3p/RPS6KA2 regulatory axis may offer a novel and effective strategy for overcoming cisplatin resistance in ovarian cancer.展开更多
Bamboo was one of the first plants to be cultivated in China and is widely used in industry and daily life.The study of gene function has become an important part of bamboo breeding,whereas quantitative real-time PCR(...Bamboo was one of the first plants to be cultivated in China and is widely used in industry and daily life.The study of gene function has become an important part of bamboo breeding,whereas quantitative real-time PCR(qRT-PCR)is a powerful tool for gene expression analysis.The accuracy of qRT-PCR results largely depends on suitable reference genes.In this study,a transcriptome-wide identification of reference genes was conducted based on 447 transcriptome datasets,comprising 200 tissue samples,107 treated samples,and 140 samples from various moso bamboo(Phyllostachys edulis)forms.A total of 3444,1013,and 3962 stably expressed genes were identified from these three groups,respectively.Functional enrichment analysis revealed significant enrichment of these genes in pathways,including the spliceosome,proteasome,and oxidative phosphorylation.Eight candidate genes(ADPRE,GAPDH,TRX,TUBA,NRP,MBF,UNK,and CAM1),were selected for qRT-PCR validation using 112 samples.To assess their stability,five statistical methods(geNorm,NormFinder,BestKeeper,Delta-Ct,and RefFinder)were employed.The most suitable reference genes were ADPRE and GAPDH for different tissues,GAPDH and CAM1 for different treatments,and GAPDH and TRX for various moso bamboo forms.Overall,ADPRE and GAPDH were the most stable reference genes across all conditions,while TUBA and TRX were the least stable reference genes.In addition,a significant negative correlation was found between the Ct values of RT-qPCR and the log2TPM values from the transcriptome data(Ct=-1.534x+37.221),providing a potential method for estimating gene expression levels.The identified reference genes,particularly ADPRE and GAPDH,provide a robust set of references for gene expression studies in moso bamboo.展开更多
This paper introduces a high-precision bandgap reference(BGR)designed for battery management systems(BMS),fea-turing an ultra-low temperature coefficient(TC)and line sensitivity(LS).The BGR employs a current-mode sche...This paper introduces a high-precision bandgap reference(BGR)designed for battery management systems(BMS),fea-turing an ultra-low temperature coefficient(TC)and line sensitivity(LS).The BGR employs a current-mode scheme with chopped op-amps and internal clock generators to eliminate op-amp offset.A low dropout regulator(LDO)and a pre-regula-tor enhance output driving and LS,respectively.Curvature compensation enhances the TC by addressing higher-order nonlinear-ity.These approaches,effective near room temperature,employs trimming at both 20 and 60°C.When combined with fixed cur-vature correction currents,it achieves an ultra-low TC for each chip.Implemented in a CMOS 180 nm process,the BGR occu-pies 0.548 mm²and operates at 2.5 V with 84μA current draw from a 5 V supply.An average TC of 2.69 ppm/℃ with two-point trimming and 0.81 ppm/℃ with multi-point trimming are achieved over the temperature range of-40 to 125℃.It accommo-dates a load current of 1 mA and an LS of 42 ppm/V,making it suitable for precise BMS applications.展开更多
Protein biosynthesis by the ribosome is a fundamental biological process in living systems.Recent studies suggest that ribosomal subunits also play essential roles in cell growth and differentiation beyond their roles...Protein biosynthesis by the ribosome is a fundamental biological process in living systems.Recent studies suggest that ribosomal subunits also play essential roles in cell growth and differentiation beyond their roles in protein translation.The ribosomal subunit RPS6 has been studied for more than 50 years in various organisms,but little is known about its specific roles in certain signaling pathways.In this study,we focused on the functions of Arabidopsis RPS6A in auxin-related root growth and development.The rps6a mutant presented a series of auxin-deficient phenotypes,such as shortened primary roots,reduced lateral root numbers,and defective vasculatures.Treatment of the rps6a mutant with various concentrations of auxin and its analogs did not restore the root defect phenotypes,suggesting a defect in the auxin signaling pathway.Further cell biological and global transcriptome analyses revealed that auxin signaling was weakened in the rps6a mutant and that there was a reduced abundance of PIN-FORMED(PIN)auxin transporters.Our work provides insights into the role of the protein biosynthesis pathway involved in auxin signaling.展开更多
Serial-parallel manipulators are of great interest to academic community in recent years,especially those composed of classical parallel mechanisms.There have been many studies around 2(3RPS)and 2(3SPR)S-PMs,but unfor...Serial-parallel manipulators are of great interest to academic community in recent years,especially those composed of classical parallel mechanisms.There have been many studies around 2(3RPS)and 2(3SPR)S-PMs,but unfortunately their inverse kinematics have not yet been resolved.This paper discovers that the unknown kinematic parameters of middle platform are responsible for the unresolvable of inverse kinematics,meanwhile the unknown kinematic parameters of middle platform also have huge coupling relationships.Therefore,to break through this challenges,the huge coupling relationships are decoupled layer by layer,the kinematic parameters of middle platform are solved by combining Sylvester's elimination method,and the inverse displacements of 2(3RPS)and 2(3SPR)S-PMs are obtained subsequently.This paper not only solves the inverse kinematics of classical 2(3RPS)and 2(3SPR)S-PMs,but also reveals the essence of the inverse kinematics of general(3-DOF)+(3-DOF)6-DOF S-PMs and proposes a corresponding solution.展开更多
Introduction: Childbirth on a scarred uterus is a major issue for health centers, especially peripheral, due to the major obstetric risks it presents. The objectives were to evaluate the frequency, route of delivery a...Introduction: Childbirth on a scarred uterus is a major issue for health centers, especially peripheral, due to the major obstetric risks it presents. The objectives were to evaluate the frequency, route of delivery and maternal-fetal prognosis of this type of delivery at csref of Kolondiéba. Materials and Methods: This was a retrospective cross-sectional study for one year (1 January 2023-31 December 2023). All patients admitted to the maternity ward of the center with at least one uterine scar and treated in the center were included. We extracted data from partograms, OR records, birth records and obstetric records. Input was done on Excel 2010 and analysis on SPSS.23. Results: The frequency of scarring uterus was 16.8% (217/1285 births). The average age was 27. Pauciparous were most represented (59%). Patients were received from community health centers (44.7%). Prenatal consultation sessions (1 - 3 sessions) were performed at (64.9%). Uterine scars were obstetric in (99%). The cesarean section was performed immediately in (59.4%), it was prophylactic in 17%. The uterine test was attempted in (25.34%) with (69%) success. We recorded 3.6% uterine ruptures, 8.7% postoperative complications, 5.5% stillbirths and one maternal death (0.46%). Conclusion: Births on a scarred uterus are frequent and associated with a high rate of complications.展开更多
Computed tomography is an indispensable X-ray imaging modality used to diagnose numerous pathologies, but it can also involve the delivery of high ionizing radiation doses harmful to the health of patients. This study...Computed tomography is an indispensable X-ray imaging modality used to diagnose numerous pathologies, but it can also involve the delivery of high ionizing radiation doses harmful to the health of patients. This study aims to survey the level of radiation doses delivered to child patients during head exams in CT imaging to set up the Dosimetric Reference Levels (DRLs), a routine dose optimization tool, based on data acquired at the University Hospital of Angré (UHA), the University Hospital of Treichville (UHT) and the Polyclinic Hospital Farah (Farah) for optimizing procedures in Ivorian hospitals. Prospectively performed on 334 CT images of 186 child patients, this study was carried out on CT systems such as Hitachi Scenaria, Sinovision Insitum, and Philips Incisive used respectively at UHA, UHT and Farah. Children’s scan data were classified into four age bands: vol or dose-length product as DLP) value, whatever the hospital, increases with respect to the age of child patients. Based on the 75th percentile of the whole dose distributions, the DRLs of the CTDIvol is 54.37 mGy whatever the age groups and those of the DLP with respect to age bands are 1224.55 mGy∙cm, 1414.06 mGy∙cm, 1632.24 mGy.cm and 1544.57 mGy∙cm, respectively. The averaged values of CTDIvol and DLP smaller than the corresponding DRLs values suggest that practices in our three facilities are optimized. However, comparing our results with those from different international studies, we see that the CTDIvol and DLP values obtained in the present work are higher. These results suggest additional surveys to ensure our DRLs values and efforts from radiologists, imaging technicians and medical physicists to strengthen clinical procedures for the radiation protection of children undergoing CT scans in Côte d’Ivoire.展开更多
The purpose of this research was to evaluate radiological safety in pediatric radiology in hospitals in the Kongo Central province of the DRC. To this end, we surveyed a convenience sample of 50 health professionals, ...The purpose of this research was to evaluate radiological safety in pediatric radiology in hospitals in the Kongo Central province of the DRC. To this end, we surveyed a convenience sample of 50 health professionals, including 10 radiologists working in the hospitals covered by the survey, to assess the practice of pediatric radiology and the degree of compliance with radiation protection principles for the safety of children and the environment. We collected radiophysical parameters to calculate entrance doses in pediatric radiology in radiology departments to determine the dosimetric level by comparison with the diagnostic reference levels of the International Commission on Radiological Protection (ICRP). All in all, we found that in Kongo Central in the DRC, many health personnel surveyed reported that more than 30% of requested radiological examinations are not justified. Also, after comparing the entrance doses produced in the surveyed departments with those of the International Commission on Radiological Protection (ICRP), a statistically significant difference was found in pediatric radiology between the average doses in five out of six surveyed departments and those of the ICRP. Therefore, almost all of the surveyed departments were found to be highly irradiating in children, while excessive X-ray irradiation in children can have significant effects due to their increased sensitivity to radiation. Among the risks are: increased cancer risks, damage to developing cells, potential genetic effects, and neurological effects. This is why support for implementing radiation protection principles is a necessity to promote the safety of patients and the environment against the harmful effects of X-rays in conventional radiology.展开更多
BACKGROUND Pepsinogen(PG)and the PG I/II ratio(PGR)are critical indicators for diagnosing Helicobacter pylori infection and chronic atrophic gastritis,and assessing gastric cancer risk.Existing reference intervals(RIs...BACKGROUND Pepsinogen(PG)and the PG I/II ratio(PGR)are critical indicators for diagnosing Helicobacter pylori infection and chronic atrophic gastritis,and assessing gastric cancer risk.Existing reference intervals(RIs)often overlook age,sex,and demographic variations.Partitioned RIs,while considering these factors,fail to capture the gradual age-related physiological changes.Next-generation RIs offer a solution to this limitation.AIM To investigate age-and sex-specific dynamics of PG and establish next-generation RIs for adults and the elderly in northern China.METHODS After screening,708 healthy individuals were included in this observational study.Serum PG was measured using chemiluminescence immunoassay.Age-and sex-related effects on PG were analyzed with a two-way analysis of variance.RI partitioning was determined by the standard deviation ratio(SDR).Traditional RIs were established using a non-parametric approach.Generalized Additive Models for Location,Scale,and Shape(GAMLSS)modeled age-related trends and continuous reference percentiles for PG I and PG II.Reference limit flagging rates for both RI types were compared.RESULTS PG I and PG II levels were influenced by age(P<0.001)and sex(P<0.001),while PGR remained stable.Age-specific RIs were required for PG I(SDR=0.366)and PG II(SDR=0.424).Partitioned RIs were established for PG I and PG II,with a single RI for PGR.GAMLSS modeling revealed distinct age-dependent trajectories:PG I increased from a median of 39.75μg/L at age 20 years to 49.75μg/L at age 60 years,a 25.16%increase,after which it plateaued through age 80 years.In contrast,PG II showed a continuous rise throughout the age range,with the median value increasing from 5.07μg/L at age 20 years to 8.36μg/L at age 80 years,corresponding to a 64.89%increase.Continuous reference percentiles intuitively reflected these trends and were detailed in this study.Next-generation RIs demonstrated superior accuracy compared to partitioned RIs when applied to specific age subgroups.CONCLUSION This study elucidates the age-and sex-specific dynamics of PG and,to our knowledge,is the first to establish next-generation RIs for PG,supporting more individualized interpretation in laboratory medicine.展开更多
To solve the problem of the lack of reference material(RM)for determination of allergenic ingredients in food,a RM of cashew nut powder was developed in the study.Cashew nut powder was prepared from cashew nut kernel ...To solve the problem of the lack of reference material(RM)for determination of allergenic ingredients in food,a RM of cashew nut powder was developed in the study.Cashew nut powder was prepared from cashew nut kernel by selecting,cleaning,crushing,n-hexane degreasing and sieving treatment.The reliability and traceability of RM was verified using real-time quantitative polymerase chain reaction(qPCR)and phylogenetic tree analysis.The cashew nut powder RM showed good homogeneity,and good stability under long-term storage at 4℃and short-term simulated transportation from-20 to 45℃.The RM was determined jointly by 8 collaborative laboratories,and the characteristic CT value was 24.732,and the extended uncertainty was 1.052%(k=2).The RM was applied to verify the amplification efficiency and the limit of detection for qPCR assay,and showed good applicability.The RM could be used for method validation and quality control,for the determination of allergenic ingredients in food mixed with trace amounts of cashew nut.展开更多
The use of a stable reference gene is fundamental for achieving reliable quantitative qRT-PCR (qPCR) results. Developing and evaluating the stability of reference genes is necessary for studying the molecular mechanis...The use of a stable reference gene is fundamental for achieving reliable quantitative qRT-PCR (qPCR) results. Developing and evaluating the stability of reference genes is necessary for studying the molecular mechanisms of M. transitoria in response to drought stress. In this study, 18 candidate reference genes were selected from transcriptome sequencing data of M. transitoria according to their FPKM values under different drought stress degrees. Cluster-23533.34641 was identified as the most stable reference gene for M. transitoria under drought stress based on qPCR results and combined analysis of Genorm, NormFinder, BestKeeper, and Delta Ct algorithms. The reference genes identified in this research offer improved accuracy for quantifying target gene expression in both M. transitoria and Malus species under drought stress. This study could provide insights into the drought stress-related functional gene or factor in M. transitoria, even in Malus species.展开更多
Sulfur isotopes of S-bearing materials are powerful tools to trace various geological processes and sulfur sources in earth sciences,especially in ore deposits where sulfide-sulfate pair coprecipitates widely.However,...Sulfur isotopes of S-bearing materials are powerful tools to trace various geological processes and sulfur sources in earth sciences,especially in ore deposits where sulfide-sulfate pair coprecipitates widely.However,in-situ S isotope determination of barite is challenging without natural matrix-matched reference material.In this study,we present two natural barite reference materials(1-YS and 294-YS)for in-situ sulfur isotopic analysis.Independent LA-MC-ICP-MS laboratories were utilized to test theδ34S micron-scale homogeneity of 1-YS and 294-YS barites that have 2s repeatabilities of better than±0.45‰and±0.41‰,respectively.Meanwhile,the in-situ analysis results are consistent with the results of the bulk analysis by GS-IRMS within uncertainty.The grand meanδ~(34)S values of 1-YS(13.37‰±0.42‰,2s)and 294-YS(14.38‰±0.44‰,2s)are the final recommended values obtained from four independent laboratories.All the results confirm the suitability of 1-YS and 294-YS barite used as calibration materials with respect to in-situ S isotopic analysis.Moreover,the new developed barite reference materials were used as matrix-matched standard to calibrate the barite samples from the Huayangchuan carbonatite-hosted U-polymetallic deposit(Qinling orogenic belt,western China)to obtainδ34S values.Utilizing the temperaturedependentδ34S fractionation of barite-pyrite pair,we calculate the formation temperature of barite(i.e.,506 to 537°C)and theδ34S value of mineralizing fluid(i.e.,-7.11‰to-7.59‰)in the Huayangchuan deposit.The results indicate an involvement of sedimentary sulfur,presumably acting as a potential uranium source(e.g.,upper crustal materials)for the giant Huayangchuan deposit.展开更多
Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate change.Accurate measurement of carbonaceous aerosol is essential to reduce th...Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate change.Accurate measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source apportionment.The accurate separation of OC and EC is controversial due to the charring of OC.Therefore,the development of reference materials(RM)for the validation of OC/EC separation is an important basis for further study.Previous RMs were mainly based on ambient air sampling,which could not provide traceability of OC and EC concentration.To develop traceable RMs with known OC/EC contents,our study applied an improved aerosol generation and mixing technique,providing uniform deposition of particles on quartz filters.To generate OC aerosol with similar pyrolytic property of ambient aerosol,both water soluble organic carbon(WSOC)and water insoluble organic carbon(WIOC)were used,and amorphous carbon was selected for EC surrogate.The RMs were analyzed using different protocols.The homogeneity within the filter was validated,reaching below 2%.The long-term stability of RMs has been validated with RSD ranged from 1.7%–3.2%.Good correlationwas observed between nominal concentration of RMswithmeasured concentration by two protocols,while the difference of EC concentration was within 20%.The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC,which could improve the accuracy of carbonaceous aerosol measurement.Moreover,the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.展开更多
Reference Evapotranspiration(ETo)iswidely used to assess totalwater loss between land and atmosphere due to its importance in maintaining the atmospheric water balance,especially in agricultural and environmental mana...Reference Evapotranspiration(ETo)iswidely used to assess totalwater loss between land and atmosphere due to its importance in maintaining the atmospheric water balance,especially in agricultural and environmental management.Accurate estimation of ETo is challenging due to its dependency onmultiple climatic variables,including temperature,humidity,and solar radiation,making it a complexmultivariate time-series problem.Traditional machine learning and deep learning models have been applied to forecast ETo,achieving moderate success.However,the introduction of transformer-based architectures in time-series forecasting has opened new possibilities formore precise ETo predictions.In this study,a novel algorithm for ETo forecasting is proposed,focusing on four transformer-based models:Vanilla Transformer,Informer,Autoformer,and FEDformer(Frequency Enhanced Decomposed Transformer),applied to an ETo dataset from the Andalusian region.The novelty of the proposed algorithm lies in determining optimized window sizes based on seasonal trends and variations,which were then used with each model to enhance prediction accuracy.This custom window-sizing method allows the models to capture ETo’s unique seasonal patterns more effectively.Finally,results demonstrate that the Informer model outperformed other transformer-based models,achievingmean square error(MSE)values of 0.1404 and 0.1445 for forecast windows(15,7)and(30,15),respectively.The Vanilla Transformer also showed strong performance,closely following the Informermodel.These findings suggest that the proposed optimized window-sizing approach,combined with transformer-based architectures,is highly effective for ETo modelling.This novel strategy has the potential to be adapted in othermultivariate time-series forecasting tasks that require seasonality-sensitive approaches.展开更多
This brief presents a cryogenic voltage reference circuit designed to operate effectively across a wide temperature range from 30 to 300 K.A key feature of the proposed design is utilizing a current subtraction techni...This brief presents a cryogenic voltage reference circuit designed to operate effectively across a wide temperature range from 30 to 300 K.A key feature of the proposed design is utilizing a current subtraction technique for temperature compensation of the reference current,avoiding the deployment of bipolar transistors to reduce area and power consumption.Implemented with a 0.18-μm CMOS process,the circuit achieves a temperature coefficient(TC)of 67.5 ppm/K,which was not achieved in previous works.The design can also attain a power supply rejection(PSR)of 58 d B at 10 k Hz.Meanwhile,the average reference voltage is 1.2 V within a 1.6%3σ-accuracy spread.Additionally,the design is characterized by a minimal power dissipation of 1μW at 30 K and a compact chip area of 0.0035 mm~2.展开更多
Reference crop evapotranspiration(ET_(0)) is essential for determining crop water requirements and developing irrigation strategies.In this study,ET_(0) was calculated via the FAO-56 Penman-Monteith model,and the spat...Reference crop evapotranspiration(ET_(0)) is essential for determining crop water requirements and developing irrigation strategies.In this study,ET_(0) was calculated via the FAO-56 Penman-Monteith model,and the spatiotemporal variations in ET_(0) over China from 1960 to 2019 were analyzed.We then quantified the contributions of five driving factors(air temperature,wind speed,relative humidity,sunshine hours,and CO_(2) concentration)to the ET_(0) trends via a detrending experiment.The results revealed that nationwide ET_(0) showed no significant(p>0.05)decreasing trend from 1960 to 2019,with a trend of−8.56×10^(−2)mm a^(−2).The average temperature and wind speed were identified as the dominant factors affecting ET_(0)trends at the national scale.The contributions of the driving factors to the ET_(0) trends were ranked in the following order:average temperature(21.3%)>wind speed(−15.63%)>sunshine hours(−11.99%)>CO_(2) concentration(6.36%)>relative humidity(3.58%).Spatially,the dominant factors influencing the ET_(0) trends varied widely.In the southeastern region,average temperature and sunshine hours dominated the trends of ET_(0),whereas wind speed and average temperature were the dominant factors in the northwestern region.The findings provide valuable insights into the dominant factors affecting ET_(0)trends in China and highlight the importance of considering different driving factors in calculating crop water requirements.展开更多
文摘Quantitative real-time PCR(qPCR)is widely used for gene expression analysis,but its accuracy critically depends on stable internal reference genes for normalization.In marine invertebrates,especially non-model taxa such as cephalopods,systematic evaluation of reference genes is limited,leading to potential bias.The cuttlefish Sepiella japonica is ecologically and economically important in China,yet previous molecular studies have often relied on single unvalidated reference genes,which may compromise data reliability.This study aimed to systematically evaluate the stability of five commonly used reference genes(18S,ef-1α,ef-1γ,gapdh,andβ-actin)across multiple tissues and sexes of S.japonica,and to identify the most suitable reference genes and optimal number for qPCR normalization.Fifteen to sixteen tissue types were collected from ten healthy adults(five males and five females).Total RNA was extracted,reverse-transcribed,and analyzed by qPCR.Gene stability was assessed using four algorithms(geNorm,NormFinder,BestKeeper,andΔCt)integrated with RefFinder,and the optimal gene number was determined using geNorm pairwise variation(V_(n/n+1)<0.15).Four transcriptome-derived genes(creld2,cd109,acy1,and miox)were used for validation.The C_(t)values of the five genes ranged from 15.47 to 20.83.β-actin and gapdh showed pronounced variability in expression stability among tissues and sexes,indicating their limited suitability for normalization.18S exhibited the highest expression(mean C_(t):15.47-16.29)and lowest variability but displayed sex-biased expression,whereas ef-1αand ef-1γremained consistently stable across most tissues in both sexes,with ef-1αbeing the most robust and showing no sex-related bias.Although specific rankings varied among tissues and sexes,the comprehensive results indicated that ef-1αand ef-1γpossessed the highest overall stability,followed by 18S,whileβ-actin and gapdh were the least stable.The final comprehensive rankings were ef-1γ>ef-1α>18S>gapdh>β-actin(male)and ef-1α>ef-1γ>18S>gapdh>β-actin(female).geNorm analysis(V2/3<0.15)indicated that two genes,mainly ef-1αand ef-1γ,were generally sufficient for reliable normalization in most tissues.Validation confirmed that normalization using the stable ef-1αand ef-1γaccurately reflected the expression differences among tissues,whereasβ-actin and gapdh can bias or confound statistical analyses.ef-1αand ef-1γare identified as the most reliable reference gene combination for qPCR analysis in S.japonica,while 18S can serve as an auxiliary gene for within-sex comparisons.The use ofβ-actin or gapdh alone is not recommended.This study establishes a systematic framework for selecting reliable reference genes in S.japonica,thereby facilitating robust qPCR normalization and providing a foundation for future gene expression research in S.japonica and other cephalopods.
基金supported by the Academic Leader Training Programof Pudong New Area Health System in Shanghai(Grant No.PWRd2021-13)Shanghai Municipal Health Commission(Grant No.202340094).
文摘Objectives:Ribosomal protein S6 kinase A2(RPS6KA2)has been identified as a potential prognostic biomarker in several cancers,including breast cancer,glioblastoma,and prostate cancer.However,its functional significance in ovarian cancer is not well characterized.This study was designed to explore the therapeutic relevance of modulating RPS6KA2 in the context of ovarian cancer,particularly in relation to cisplatin resistance.Methods:The expression levels of RPS6KA2 and key regulators involved in autophagy and ferroptosis were assessed using quantitative reverse transcription-PCR,immunofluorescence staining,immunohistochemistry,and western blotting.Prognostic associations were conducted using the Kaplan-Meier Plotter database.Autophagy flux assays and visualization of autophagosomes were performed to assess autophagy activity.Ferroptosis-related parameters,including intracellular iron content,glutathione(GSH)levels,reactive oxygen species(ROS)generation,and mitochondrial membrane potential,were measured to determine ferroptotic changes.In vivo experiments were carried out to determine the antitumor efficacy of RPS6KA2 modulation in combination with pathway-specific agents.Results:Using ovarian cancer cell lines and clinical tissue samples,we demonstrated that RPS6KA2 expression was significantly downregulated in cisplatin-resistant cells and tissues compared to their sensitive counterparts.Low RPS6KA2 expression correlated with unfavorable patient outcomes and enhanced chemoresistance.Mechanistically,RPS6KA2 inhibited autophagy by modulating the phosphatidylinositol 3-kinase-protein kinase B-mammalian target of rapamycin(PI3K-AKT-mTOR)signaling pathway,which in turn increased sensitivity to cisplatin.Additionally,RPS6KA2 facilitated ferroptosis,contributing to its tumor-suppressive function.miR-512-3p was identified as a negative regulator of RPS6KA2,driving cisplatin resistance through suppression of RPS6KA2 expression.In vivo validation confirmed that combining RPS6KA2 targeting with autophagy inhibitors or ferroptosis inducers significantly enhanced cisplatin sensitivity in ovarian cancer models.Conclusion:These results collectively indicate that targeting the miR-512-3p/RPS6KA2 regulatory axis may offer a novel and effective strategy for overcoming cisplatin resistance in ovarian cancer.
基金supported by the National Key Research and Development Program of China(Grant No.2021YFD2200502)the National Natural Science Foundation of China(Grant No.31971736).
文摘Bamboo was one of the first plants to be cultivated in China and is widely used in industry and daily life.The study of gene function has become an important part of bamboo breeding,whereas quantitative real-time PCR(qRT-PCR)is a powerful tool for gene expression analysis.The accuracy of qRT-PCR results largely depends on suitable reference genes.In this study,a transcriptome-wide identification of reference genes was conducted based on 447 transcriptome datasets,comprising 200 tissue samples,107 treated samples,and 140 samples from various moso bamboo(Phyllostachys edulis)forms.A total of 3444,1013,and 3962 stably expressed genes were identified from these three groups,respectively.Functional enrichment analysis revealed significant enrichment of these genes in pathways,including the spliceosome,proteasome,and oxidative phosphorylation.Eight candidate genes(ADPRE,GAPDH,TRX,TUBA,NRP,MBF,UNK,and CAM1),were selected for qRT-PCR validation using 112 samples.To assess their stability,five statistical methods(geNorm,NormFinder,BestKeeper,Delta-Ct,and RefFinder)were employed.The most suitable reference genes were ADPRE and GAPDH for different tissues,GAPDH and CAM1 for different treatments,and GAPDH and TRX for various moso bamboo forms.Overall,ADPRE and GAPDH were the most stable reference genes across all conditions,while TUBA and TRX were the least stable reference genes.In addition,a significant negative correlation was found between the Ct values of RT-qPCR and the log2TPM values from the transcriptome data(Ct=-1.534x+37.221),providing a potential method for estimating gene expression levels.The identified reference genes,particularly ADPRE and GAPDH,provide a robust set of references for gene expression studies in moso bamboo.
基金supported by the National Natural Science Foundation of China(NSFC)under grant No.62204235。
文摘This paper introduces a high-precision bandgap reference(BGR)designed for battery management systems(BMS),fea-turing an ultra-low temperature coefficient(TC)and line sensitivity(LS).The BGR employs a current-mode scheme with chopped op-amps and internal clock generators to eliminate op-amp offset.A low dropout regulator(LDO)and a pre-regula-tor enhance output driving and LS,respectively.Curvature compensation enhances the TC by addressing higher-order nonlinear-ity.These approaches,effective near room temperature,employs trimming at both 20 and 60°C.When combined with fixed cur-vature correction currents,it achieves an ultra-low TC for each chip.Implemented in a CMOS 180 nm process,the BGR occu-pies 0.548 mm²and operates at 2.5 V with 84μA current draw from a 5 V supply.An average TC of 2.69 ppm/℃ with two-point trimming and 0.81 ppm/℃ with multi-point trimming are achieved over the temperature range of-40 to 125℃.It accommo-dates a load current of 1 mA and an LS of 42 ppm/V,making it suitable for precise BMS applications.
基金supported by the National Natural Science Foundation of China(32321001)the Forestry Bureau of Anhui Province(AHLYJBGS-2024-01)+3 种基金the Center for Advanced Interdisciplinary Science and Biomedicine of IHM,the Division of Life Sciences and Medicine,the University of Science and Technology of China(QYPY20220012)the USTC Research Funds of the Double First-Class Initiative(YD9100002016)start-up funding from the University of Science and Technology of China and the Chinese Academy of Sciences(GG9100007007,KY9100000026,KY9100000051,KJ2070000079)the Fundamental Research Funds for the Central Universities(WK9100000021)。
文摘Protein biosynthesis by the ribosome is a fundamental biological process in living systems.Recent studies suggest that ribosomal subunits also play essential roles in cell growth and differentiation beyond their roles in protein translation.The ribosomal subunit RPS6 has been studied for more than 50 years in various organisms,but little is known about its specific roles in certain signaling pathways.In this study,we focused on the functions of Arabidopsis RPS6A in auxin-related root growth and development.The rps6a mutant presented a series of auxin-deficient phenotypes,such as shortened primary roots,reduced lateral root numbers,and defective vasculatures.Treatment of the rps6a mutant with various concentrations of auxin and its analogs did not restore the root defect phenotypes,suggesting a defect in the auxin signaling pathway.Further cell biological and global transcriptome analyses revealed that auxin signaling was weakened in the rps6a mutant and that there was a reduced abundance of PIN-FORMED(PIN)auxin transporters.Our work provides insights into the role of the protein biosynthesis pathway involved in auxin signaling.
基金Supported by National Natural Science Foundation of China(Grant No.52275033)National Natural Science Youth Foundation of China(Grant No.52205033)Hebei Provincial Natural Science Foundation of China(Grant No.E2021203019)。
文摘Serial-parallel manipulators are of great interest to academic community in recent years,especially those composed of classical parallel mechanisms.There have been many studies around 2(3RPS)and 2(3SPR)S-PMs,but unfortunately their inverse kinematics have not yet been resolved.This paper discovers that the unknown kinematic parameters of middle platform are responsible for the unresolvable of inverse kinematics,meanwhile the unknown kinematic parameters of middle platform also have huge coupling relationships.Therefore,to break through this challenges,the huge coupling relationships are decoupled layer by layer,the kinematic parameters of middle platform are solved by combining Sylvester's elimination method,and the inverse displacements of 2(3RPS)and 2(3SPR)S-PMs are obtained subsequently.This paper not only solves the inverse kinematics of classical 2(3RPS)and 2(3SPR)S-PMs,but also reveals the essence of the inverse kinematics of general(3-DOF)+(3-DOF)6-DOF S-PMs and proposes a corresponding solution.
文摘Introduction: Childbirth on a scarred uterus is a major issue for health centers, especially peripheral, due to the major obstetric risks it presents. The objectives were to evaluate the frequency, route of delivery and maternal-fetal prognosis of this type of delivery at csref of Kolondiéba. Materials and Methods: This was a retrospective cross-sectional study for one year (1 January 2023-31 December 2023). All patients admitted to the maternity ward of the center with at least one uterine scar and treated in the center were included. We extracted data from partograms, OR records, birth records and obstetric records. Input was done on Excel 2010 and analysis on SPSS.23. Results: The frequency of scarring uterus was 16.8% (217/1285 births). The average age was 27. Pauciparous were most represented (59%). Patients were received from community health centers (44.7%). Prenatal consultation sessions (1 - 3 sessions) were performed at (64.9%). Uterine scars were obstetric in (99%). The cesarean section was performed immediately in (59.4%), it was prophylactic in 17%. The uterine test was attempted in (25.34%) with (69%) success. We recorded 3.6% uterine ruptures, 8.7% postoperative complications, 5.5% stillbirths and one maternal death (0.46%). Conclusion: Births on a scarred uterus are frequent and associated with a high rate of complications.
文摘Computed tomography is an indispensable X-ray imaging modality used to diagnose numerous pathologies, but it can also involve the delivery of high ionizing radiation doses harmful to the health of patients. This study aims to survey the level of radiation doses delivered to child patients during head exams in CT imaging to set up the Dosimetric Reference Levels (DRLs), a routine dose optimization tool, based on data acquired at the University Hospital of Angré (UHA), the University Hospital of Treichville (UHT) and the Polyclinic Hospital Farah (Farah) for optimizing procedures in Ivorian hospitals. Prospectively performed on 334 CT images of 186 child patients, this study was carried out on CT systems such as Hitachi Scenaria, Sinovision Insitum, and Philips Incisive used respectively at UHA, UHT and Farah. Children’s scan data were classified into four age bands: vol or dose-length product as DLP) value, whatever the hospital, increases with respect to the age of child patients. Based on the 75th percentile of the whole dose distributions, the DRLs of the CTDIvol is 54.37 mGy whatever the age groups and those of the DLP with respect to age bands are 1224.55 mGy∙cm, 1414.06 mGy∙cm, 1632.24 mGy.cm and 1544.57 mGy∙cm, respectively. The averaged values of CTDIvol and DLP smaller than the corresponding DRLs values suggest that practices in our three facilities are optimized. However, comparing our results with those from different international studies, we see that the CTDIvol and DLP values obtained in the present work are higher. These results suggest additional surveys to ensure our DRLs values and efforts from radiologists, imaging technicians and medical physicists to strengthen clinical procedures for the radiation protection of children undergoing CT scans in Côte d’Ivoire.
文摘The purpose of this research was to evaluate radiological safety in pediatric radiology in hospitals in the Kongo Central province of the DRC. To this end, we surveyed a convenience sample of 50 health professionals, including 10 radiologists working in the hospitals covered by the survey, to assess the practice of pediatric radiology and the degree of compliance with radiation protection principles for the safety of children and the environment. We collected radiophysical parameters to calculate entrance doses in pediatric radiology in radiology departments to determine the dosimetric level by comparison with the diagnostic reference levels of the International Commission on Radiological Protection (ICRP). All in all, we found that in Kongo Central in the DRC, many health personnel surveyed reported that more than 30% of requested radiological examinations are not justified. Also, after comparing the entrance doses produced in the surveyed departments with those of the International Commission on Radiological Protection (ICRP), a statistically significant difference was found in pediatric radiology between the average doses in five out of six surveyed departments and those of the ICRP. Therefore, almost all of the surveyed departments were found to be highly irradiating in children, while excessive X-ray irradiation in children can have significant effects due to their increased sensitivity to radiation. Among the risks are: increased cancer risks, damage to developing cells, potential genetic effects, and neurological effects. This is why support for implementing radiation protection principles is a necessity to promote the safety of patients and the environment against the harmful effects of X-rays in conventional radiology.
文摘BACKGROUND Pepsinogen(PG)and the PG I/II ratio(PGR)are critical indicators for diagnosing Helicobacter pylori infection and chronic atrophic gastritis,and assessing gastric cancer risk.Existing reference intervals(RIs)often overlook age,sex,and demographic variations.Partitioned RIs,while considering these factors,fail to capture the gradual age-related physiological changes.Next-generation RIs offer a solution to this limitation.AIM To investigate age-and sex-specific dynamics of PG and establish next-generation RIs for adults and the elderly in northern China.METHODS After screening,708 healthy individuals were included in this observational study.Serum PG was measured using chemiluminescence immunoassay.Age-and sex-related effects on PG were analyzed with a two-way analysis of variance.RI partitioning was determined by the standard deviation ratio(SDR).Traditional RIs were established using a non-parametric approach.Generalized Additive Models for Location,Scale,and Shape(GAMLSS)modeled age-related trends and continuous reference percentiles for PG I and PG II.Reference limit flagging rates for both RI types were compared.RESULTS PG I and PG II levels were influenced by age(P<0.001)and sex(P<0.001),while PGR remained stable.Age-specific RIs were required for PG I(SDR=0.366)and PG II(SDR=0.424).Partitioned RIs were established for PG I and PG II,with a single RI for PGR.GAMLSS modeling revealed distinct age-dependent trajectories:PG I increased from a median of 39.75μg/L at age 20 years to 49.75μg/L at age 60 years,a 25.16%increase,after which it plateaued through age 80 years.In contrast,PG II showed a continuous rise throughout the age range,with the median value increasing from 5.07μg/L at age 20 years to 8.36μg/L at age 80 years,corresponding to a 64.89%increase.Continuous reference percentiles intuitively reflected these trends and were detailed in this study.Next-generation RIs demonstrated superior accuracy compared to partitioned RIs when applied to specific age subgroups.CONCLUSION This study elucidates the age-and sex-specific dynamics of PG and,to our knowledge,is the first to establish next-generation RIs for PG,supporting more individualized interpretation in laboratory medicine.
基金supported by the National Key Research and Development Pro-gram of China(2021YFF0601902)the National Reference Material Development Project(S2022234).
文摘To solve the problem of the lack of reference material(RM)for determination of allergenic ingredients in food,a RM of cashew nut powder was developed in the study.Cashew nut powder was prepared from cashew nut kernel by selecting,cleaning,crushing,n-hexane degreasing and sieving treatment.The reliability and traceability of RM was verified using real-time quantitative polymerase chain reaction(qPCR)and phylogenetic tree analysis.The cashew nut powder RM showed good homogeneity,and good stability under long-term storage at 4℃and short-term simulated transportation from-20 to 45℃.The RM was determined jointly by 8 collaborative laboratories,and the characteristic CT value was 24.732,and the extended uncertainty was 1.052%(k=2).The RM was applied to verify the amplification efficiency and the limit of detection for qPCR assay,and showed good applicability.The RM could be used for method validation and quality control,for the determination of allergenic ingredients in food mixed with trace amounts of cashew nut.
基金supported by the Natural Science Foundation of Qinghai Province(2022-ZJ-902).
文摘The use of a stable reference gene is fundamental for achieving reliable quantitative qRT-PCR (qPCR) results. Developing and evaluating the stability of reference genes is necessary for studying the molecular mechanisms of M. transitoria in response to drought stress. In this study, 18 candidate reference genes were selected from transcriptome sequencing data of M. transitoria according to their FPKM values under different drought stress degrees. Cluster-23533.34641 was identified as the most stable reference gene for M. transitoria under drought stress based on qPCR results and combined analysis of Genorm, NormFinder, BestKeeper, and Delta Ct algorithms. The reference genes identified in this research offer improved accuracy for quantifying target gene expression in both M. transitoria and Malus species under drought stress. This study could provide insights into the drought stress-related functional gene or factor in M. transitoria, even in Malus species.
基金supported by the National Natural Science Foundation of China(Nos.42003014,42363004,42073051,42303023)Jiangxi Provincial Natural Science Foundation(No.20232BAB213070)the Natural Science Foundation of Shandong Province(No.ZR2022QD050)。
文摘Sulfur isotopes of S-bearing materials are powerful tools to trace various geological processes and sulfur sources in earth sciences,especially in ore deposits where sulfide-sulfate pair coprecipitates widely.However,in-situ S isotope determination of barite is challenging without natural matrix-matched reference material.In this study,we present two natural barite reference materials(1-YS and 294-YS)for in-situ sulfur isotopic analysis.Independent LA-MC-ICP-MS laboratories were utilized to test theδ34S micron-scale homogeneity of 1-YS and 294-YS barites that have 2s repeatabilities of better than±0.45‰and±0.41‰,respectively.Meanwhile,the in-situ analysis results are consistent with the results of the bulk analysis by GS-IRMS within uncertainty.The grand meanδ~(34)S values of 1-YS(13.37‰±0.42‰,2s)and 294-YS(14.38‰±0.44‰,2s)are the final recommended values obtained from four independent laboratories.All the results confirm the suitability of 1-YS and 294-YS barite used as calibration materials with respect to in-situ S isotopic analysis.Moreover,the new developed barite reference materials were used as matrix-matched standard to calibrate the barite samples from the Huayangchuan carbonatite-hosted U-polymetallic deposit(Qinling orogenic belt,western China)to obtainδ34S values.Utilizing the temperaturedependentδ34S fractionation of barite-pyrite pair,we calculate the formation temperature of barite(i.e.,506 to 537°C)and theδ34S value of mineralizing fluid(i.e.,-7.11‰to-7.59‰)in the Huayangchuan deposit.The results indicate an involvement of sedimentary sulfur,presumably acting as a potential uranium source(e.g.,upper crustal materials)for the giant Huayangchuan deposit.
基金supported by the National Natural Science Foundation of China(No.22206180)the funds for establishing basic quality and technology capabilities(No.ANL2203)the special fund for basic scientific research business of central public research institutes(No.AKYZD2207-4)。
文摘Carbonaceous aerosol,including organic carbon(OC)and elemental carbon(EC),has significant influence on human health,air quality and climate change.Accurate measurement of carbonaceous aerosol is essential to reduce the uncertainty of radiative forcing estimation and source apportionment.The accurate separation of OC and EC is controversial due to the charring of OC.Therefore,the development of reference materials(RM)for the validation of OC/EC separation is an important basis for further study.Previous RMs were mainly based on ambient air sampling,which could not provide traceability of OC and EC concentration.To develop traceable RMs with known OC/EC contents,our study applied an improved aerosol generation and mixing technique,providing uniform deposition of particles on quartz filters.To generate OC aerosol with similar pyrolytic property of ambient aerosol,both water soluble organic carbon(WSOC)and water insoluble organic carbon(WIOC)were used,and amorphous carbon was selected for EC surrogate.The RMs were analyzed using different protocols.The homogeneity within the filter was validated,reaching below 2%.The long-term stability of RMs has been validated with RSD ranged from 1.7%–3.2%.Good correlationwas observed between nominal concentration of RMswithmeasured concentration by two protocols,while the difference of EC concentration was within 20%.The results indicated that the newly developed RMs were acceptable for the calibration of OC and EC,which could improve the accuracy of carbonaceous aerosol measurement.Moreover,the laboratory-generated EC-RMs could be suitable for the calibration of equivalent BC concentration by Aethalometers.
基金funded by Princess Nourah bint Abdulrahman University and Researchers Supporting Project number(PNURSP2024R136),Princess Nourah bint Abdulrahman University,Riyadh,Saudi Arabia.
文摘Reference Evapotranspiration(ETo)iswidely used to assess totalwater loss between land and atmosphere due to its importance in maintaining the atmospheric water balance,especially in agricultural and environmental management.Accurate estimation of ETo is challenging due to its dependency onmultiple climatic variables,including temperature,humidity,and solar radiation,making it a complexmultivariate time-series problem.Traditional machine learning and deep learning models have been applied to forecast ETo,achieving moderate success.However,the introduction of transformer-based architectures in time-series forecasting has opened new possibilities formore precise ETo predictions.In this study,a novel algorithm for ETo forecasting is proposed,focusing on four transformer-based models:Vanilla Transformer,Informer,Autoformer,and FEDformer(Frequency Enhanced Decomposed Transformer),applied to an ETo dataset from the Andalusian region.The novelty of the proposed algorithm lies in determining optimized window sizes based on seasonal trends and variations,which were then used with each model to enhance prediction accuracy.This custom window-sizing method allows the models to capture ETo’s unique seasonal patterns more effectively.Finally,results demonstrate that the Informer model outperformed other transformer-based models,achievingmean square error(MSE)values of 0.1404 and 0.1445 for forecast windows(15,7)and(30,15),respectively.The Vanilla Transformer also showed strong performance,closely following the Informermodel.These findings suggest that the proposed optimized window-sizing approach,combined with transformer-based architectures,is highly effective for ETo modelling.This novel strategy has the potential to be adapted in othermultivariate time-series forecasting tasks that require seasonality-sensitive approaches.
基金supported in part by the National Key Research and Development Program of China(2021YFA0715503)。
文摘This brief presents a cryogenic voltage reference circuit designed to operate effectively across a wide temperature range from 30 to 300 K.A key feature of the proposed design is utilizing a current subtraction technique for temperature compensation of the reference current,avoiding the deployment of bipolar transistors to reduce area and power consumption.Implemented with a 0.18-μm CMOS process,the circuit achieves a temperature coefficient(TC)of 67.5 ppm/K,which was not achieved in previous works.The design can also attain a power supply rejection(PSR)of 58 d B at 10 k Hz.Meanwhile,the average reference voltage is 1.2 V within a 1.6%3σ-accuracy spread.Additionally,the design is characterized by a minimal power dissipation of 1μW at 30 K and a compact chip area of 0.0035 mm~2.
基金National Natural Science Foundation of China,No.42277191,No.42377072,No.42107087。
文摘Reference crop evapotranspiration(ET_(0)) is essential for determining crop water requirements and developing irrigation strategies.In this study,ET_(0) was calculated via the FAO-56 Penman-Monteith model,and the spatiotemporal variations in ET_(0) over China from 1960 to 2019 were analyzed.We then quantified the contributions of five driving factors(air temperature,wind speed,relative humidity,sunshine hours,and CO_(2) concentration)to the ET_(0) trends via a detrending experiment.The results revealed that nationwide ET_(0) showed no significant(p>0.05)decreasing trend from 1960 to 2019,with a trend of−8.56×10^(−2)mm a^(−2).The average temperature and wind speed were identified as the dominant factors affecting ET_(0)trends at the national scale.The contributions of the driving factors to the ET_(0) trends were ranked in the following order:average temperature(21.3%)>wind speed(−15.63%)>sunshine hours(−11.99%)>CO_(2) concentration(6.36%)>relative humidity(3.58%).Spatially,the dominant factors influencing the ET_(0) trends varied widely.In the southeastern region,average temperature and sunshine hours dominated the trends of ET_(0),whereas wind speed and average temperature were the dominant factors in the northwestern region.The findings provide valuable insights into the dominant factors affecting ET_(0)trends in China and highlight the importance of considering different driving factors in calculating crop water requirements.
