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LoRa Sense:Sensing and Optimization of LoRa Link Behavior Using Path-Loss Models in Open-Cast Mines
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作者 Bhanu Pratap Reddy Bhavanam Prashanth Ragam 《Computer Modeling in Engineering & Sciences》 SCIE EI 2025年第1期425-466,共42页
The Internet of Things(IoT)has orchestrated various domains in numerous applications,contributing significantly to the growth of the smart world,even in regions with low literacy rates,boosting socio-economic developm... The Internet of Things(IoT)has orchestrated various domains in numerous applications,contributing significantly to the growth of the smart world,even in regions with low literacy rates,boosting socio-economic development.This study provides valuable insights into optimizing wireless communication,paving the way for a more connected and productive future in the mining industry.The IoT revolution is advancing across industries,but harsh geometric environments,including open-pit mines,pose unique challenges for reliable communication.The advent of IoT in the mining industry has significantly improved communication for critical operations through the use of Radio Frequency(RF)protocols such as Bluetooth,Wi-Fi,GSM/GPRS,Narrow Band(NB)-IoT,SigFox,ZigBee,and Long Range Wireless Area Network(LoRaWAN).This study addresses the optimization of network implementations by comparing two leading free-spreading IoT-based RF protocols such as ZigBee and LoRaWAN.Intensive field tests are conducted in various opencast mines to investigate coverage potential and signal attenuation.ZigBee is tested in the Tadicherla open-cast coal mine in India.Similarly,LoRaWAN field tests are conducted at one of the associated cement companies(ACC)in the limestone mine in Bargarh,India,covering both Indoor-toOutdoor(I2O)and Outdoor-to-Outdoor(O2O)environments.A robust framework of path-loss models,referred to as Free space,Egli,Okumura-Hata,Cost231-Hata and Ericsson models,combined with key performance metrics,is employed to evaluate the patterns of signal attenuation.Extensive field testing and careful data analysis revealed that the Egli model is the most consistent path-loss model for the ZigBee protocol in an I2O environment,with a coefficient of determination(R^(2))of 0.907,balanced error metrics such as Normalized Root Mean Square Error(NRMSE)of 0.030,Mean Square Error(MSE)of 4.950,Mean Absolute Percentage Error(MAPE)of 0.249 and Scatter Index(SI)of 2.723.In the O2O scenario,the Ericsson model showed superior performance,with the highest R^(2)value of 0.959,supported by strong correlation metrics:NRMSE of 0.026,MSE of 8.685,MAPE of 0.685,Mean Absolute Deviation(MAD)of 20.839 and SI of 2.194.For the LoRaWAN protocol,the Cost-231 model achieved the highest R^(2)value of 0.921 in the I2O scenario,complemented by the lowest metrics:NRMSE of 0.018,MSE of 1.324,MAPE of 0.217,MAD of 9.218 and SI of 1.238.In the O2O environment,the Okumura-Hata model achieved the highest R^(2)value of 0.978,indicating a strong fit with metrics NRMSE of 0.047,MSE of 27.807,MAPE of 27.494,MAD of 37.287 and SI of 3.927.This advancement in reliable communication networks promises to transform the opencast landscape into networked signal attenuation.These results support decision-making for mining needs and ensure reliable communications even in the face of formidable obstacles. 展开更多
关键词 Internet of things long range wireless area network ZigBee mining environments path-loss models coefficient of determination mean square error
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Determinants of generalized anxiety and construction of a predictive model in patients with chronic obstructive pulmonary disease
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作者 Yi-Pu Zhao Wei-Hua Liu Qun-Cheng Zhang 《World Journal of Psychiatry》 2025年第2期48-58,共11页
BACKGROUND Patients with chronic obstructive pulmonary disease(COPD)frequently experience exacerbations requiring multiple hospitalizations over prolonged disease courses,which predispose them to generalized anxiety d... BACKGROUND Patients with chronic obstructive pulmonary disease(COPD)frequently experience exacerbations requiring multiple hospitalizations over prolonged disease courses,which predispose them to generalized anxiety disorder(GAD).This comorbidity exacerbates breathing difficulties,activity limitations,and social isolation.While previous studies predominantly employed the GAD 7-item scale for screening,this approach is somewhat subjective.The current literature on predictive models for GAD risk in patients with COPD is limited.AIM To construct and validate a GAD risk prediction model to aid healthcare professionals in preventing the onset of GAD.METHODS This retrospective analysis encompassed patients with COPD treated at our institution from July 2021 to February 2024.The patients were categorized into a modeling(MO)group and a validation(VA)group in a 7:3 ratio on the basis of the occurrence of GAD.Univariate and multivariate logistic regression analyses were utilized to construct the risk prediction model,which was visualized using forest plots.The model’s performance was evaluated using Hosmer-Lemeshow(H-L)goodness-of-fit test and receiver operating characteristic(ROC)curve analysis.RESULTS A total of 271 subjects were included,with 190 in the MO group and 81 in the VA group.GAD was identified in 67 patients with COPD,resulting in a prevalence rate of 24.72%(67/271),with 49 cases(18.08%)in the MO group and 18 cases(22.22%)in the VA group.Significant differences were observed between patients with and without GAD in terms of educational level,average household income,smoking history,smoking index,number of exacerbations in the past year,cardiovascular comorbidities,disease knowledge,and personality traits(P<0.05).Multivariate logistic regression analysis revealed that lower education levels,household income<3000 China yuan,smoking history,smoking index≥400 cigarettes/year,≥two exacerbations in the past year,cardiovascular comorbidities,complete lack of disease information,and introverted personality were significant risk factors for GAD in the MO group(P<0.05).ROC analysis indicated that the area under the curve for predicting GAD in the MO and VA groups was 0.978 and 0.960.The H-L test yieldedχ^(2) values of 6.511 and 5.179,with P=0.275 and 0.274.Calibration curves demonstrated good agreement between predicted and actual GAD occurrence risks.CONCLUSION The developed predictive model includes eight independent risk factors:Educational level,household income,smoking history,smoking index,number of exacerbations in the past year,presence of cardiovascular comorbidities,level of disease knowledge,and personality traits.This model effectively predicts the onset of GAD in patients with COPD,enabling early identification of high-risk individuals and providing a basis for early preventive interventions by nursing staff. 展开更多
关键词 Chronic obstructive pulmonary disease Generalized anxiety disorder Predictive model Determinants analysis Forest plot
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DETERMINE评分与急性心肌梗死PCI术预后关系的分析
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作者 李加乐 刘泽岩 程景林 《中文科技期刊数据库(引文版)医药卫生》 2024年第5期0051-0054,共4页
探讨DETERMINE评分(病理性Q波导联数*2+碎裂QRS波导联数+T波倒置导联数)与急性心肌梗死患者经皮冠状动脉介入(PCI)术后预后的关系。方法 选择2021.1-2022.12在我院住院接受PCI治疗的急性心肌梗死患者206例,根据预后情况分为预后良好组(... 探讨DETERMINE评分(病理性Q波导联数*2+碎裂QRS波导联数+T波倒置导联数)与急性心肌梗死患者经皮冠状动脉介入(PCI)术后预后的关系。方法 选择2021.1-2022.12在我院住院接受PCI治疗的急性心肌梗死患者206例,根据预后情况分为预后良好组(165例)和预后不良组(41例)。比较两组患者的临床资料及DETERMINE评分,采用多因素Logistic回归法分析影响急性心肌梗死PCI术后预后的相关因素;创建受试者工作特征曲线(ROC),分析DETERMINE评分对急性心肌梗死PCI术后预后的预测价值。分析急性心肌梗死PCI术预后不良的影响因素。结果 与预后良好组比较,预后不良组糖尿病史、心律失常史比例及DETERMINE评分、年龄、体重指数、左室射血分数、糖化血红蛋白、低密度脂蛋白胆固醇、总胆固醇水平均显著升高,差异具有统计学意义;二元Logistic回归分析显示DETERMINE评分、心律失常史、体重指数、糖化血红蛋白、低密度脂蛋白胆固醇是冠心病患者PCI手术预后不良的独立危险因素(OR=1.443~15.658,P<0.05)。结论 DETERMINE评分与冠心病PCI术预后相关,需引起临床关注。 展开更多
关键词 DETERMINE评分 急性心肌梗死 PCI术后 预后
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A Coordinate-Free Approach to the Design of Generalized Griffis-Duffy Platforms
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作者 Chengwei Shen Xu Pei +1 位作者 Lubin Hang Jingjun Yu 《Chinese Journal of Mechanical Engineering》 SCIE EI CAS CSCD 2024年第3期95-103,共9页
Architectural singularity belongs to the Type II singularity,in which a parallel manipulator(PM)gains one or more degrees of freedom and becomes uncontrollable.PMs remaining permanently in a singularity are beneficial... Architectural singularity belongs to the Type II singularity,in which a parallel manipulator(PM)gains one or more degrees of freedom and becomes uncontrollable.PMs remaining permanently in a singularity are beneficial for linearto-rotary motion conversion.Griffis-Duffy(GD)platform is a mobile structure admitting a Bricard motion.In this paper,we present a coordinate-free approach to the design of generalized GD platforms,which consists in determining the shape and attachment of both the moving platform and the fixed base.The generalized GD platform is treated as a combination of six coaxial single-loop mechanisms under the same constraints.Owing to the inversion,hidden in the geometric structure of these single-loop mechanisms,the mapping from a line to a circle establishes the geometric transformation between the fixed base and the moving platform based on the center of inversion,and describes the shape and attachment of the generalized GD platform.Moreover,the center of inversion not only identifies the location of rotation axis,but also affects the shape of the platform mechanism.A graphical construction of generalized GD platforms using inversion,proposed in the paper,provides geometrically feasible solutions of the manipulator design for the requirement of the location of rotation axis. 展开更多
关键词 Generalized Griffis-Duffy platforms SELF-MOTION INVERSION Coordinate-free determination Manipulator design
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Silencing transformer and transformer-2 in Zeugodacus cucurbitae causes defective sex determination with inviability of most pseudomales
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作者 Qin Ma Zizhen Fan +5 位作者 Ping Wang Siya Ma Jian Wen Fengqin Cao Xianwu Lin Rihui Yan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第3期938-947,共10页
transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbi... transformer is a switch gene for sex determination in many insects, which cooperates with transformer-2 that is expressed in both sexes to regulate female differentiation, particularly in dipterans. Zeugodacus cucurbitae(Coquillett) is a very destructive pest worldwide, however, its sex determination pathway remains largely uncharacterized. Here, we show that the female sex ratio is sharply reduced with knockdown of either transformer or transformer-2 by RNA interference in early embryos of Z. cucurbitae. Most of the males grown from the embryos with transient transformer and transformer-2 suppression mated with wild-type females and produced mixed sex progeny, with one exception that produced only female progeny, and all of the few remaining males failed to mate with wild-type females and produced no progeny. The exceptional male and those males with mating failure were XX pseudomales as determined by the detection of Y chromosome-linked Maleness-on-the-Y, indicating that most XX pseudomales are not viable. The phenotypes of transformer and transformer-2 suggest that they play a key role in regulating sex determination and are required for female sexual development of Z. cucurbitae. Our results will be beneficial to the understanding of sex determination in Z. cucurbitae and can facilitate the development of genetic sexing strains for its biological control. 展开更多
关键词 Zeugodacus cucurbitae TRANSFORMER transformer-2 sex determination RNA interference biological control
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Review of the Low-Lying Excited Baryons ∑^(*)(1/2^(-))
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作者 En Wang Li-Sheng Geng +2 位作者 Jia-Jun Wu Ju-Jun Xie Bing-Song Zou 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第10期31-37,共7页
Strong empirical and phenomenological indications exist for large sea-quark admixtures in the low-lying excited baryons.Investigating the low-lying excited baryon ∑^(*)(1/2^(-))is important for determining the nature... Strong empirical and phenomenological indications exist for large sea-quark admixtures in the low-lying excited baryons.Investigating the low-lying excited baryon ∑^(*)(1/2^(-))is important for determining the nature of the low-lying excited baryons.We review the experimental and theoretical progress on the studies of the ∑^(*)(1/2^(-)). 展开更多
关键词 EXCITED QUARK DETERMINING
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foxl2l is a germ cell-intrinsic gatekeeper of oogenesis in zebrafish
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作者 Zhiqin Ren Ding Ye +5 位作者 Naike Su Chaofan Wang Lijia He Houpeng Wang Mudan He Yonghua Sun 《Zoological Research》 SCIE CSCD 2024年第5期1116-1130,共15页
Zebrafish serve as a valuable model organism for studying germ cell biology and reproductive processes.The AB strain of zebrafish is proposed to exhibit a polygenic sex determination system,where most males initially ... Zebrafish serve as a valuable model organism for studying germ cell biology and reproductive processes.The AB strain of zebrafish is proposed to exhibit a polygenic sex determination system,where most males initially develop juvenile ovaries before committing to male fate.In species with chromosomal sex determination,gonadal somatic cells are recognized as key determinants of germ cell fate.Notably,the loss of germ cells in zebrafish leads to masculinization,implying that germ cells harbor an intrinsic feminization signal.However,the specific signal triggering oogenesis in zebrafish remains unclear.In the present study,we identified foxl2l as an oocyte progenitor-specific gene essential for initiating oogenesis in germ cells.Results showed that foxl2l-knockout zebrafish bypassed the juvenile ovary stage and exclusively developed into fertile males.Further analysis revealed that loss of foxl2l hindered the initiation of oocyte-specific meiosis and prevented entry into oogenesis,leading to premature spermatogenesis during early gonadal development.Furthermore,while mutation of the pro-male gene dmrt1 led to fertile female differentiation,simultaneous disruption of foxl2l in dmrt1 mutants completely blocked oogenesis,with a large proportion of germ cells arrested as germline stem cells,highlighting the crucial role of foxl2l in oogenesis.Overall,this study highlights the unique function of foxl2l as a germ cell-intrinsic gatekeeper of oogenesis in zebrafish. 展开更多
关键词 foxl2l DMRT1 OOGENESIS Sex determination MEIOSIS
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Ionization Potential Depression Model for Warm/Hot and Dense Plasmas
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作者 Chensheng Wu Fuyang Zhou +4 位作者 Jun Yan Xiang Gao Yong Wu Chunhua Zeng Jianguo Wang 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第8期45-57,共13页
For warm/hot and dense plasmas(WDPs),ionization potential depression(IPD)plays a crucial role in determining its ionization balance and understanding the resultant microscopic plasma properties.A sophisticated and uni... For warm/hot and dense plasmas(WDPs),ionization potential depression(IPD)plays a crucial role in determining its ionization balance and understanding the resultant microscopic plasma properties.A sophisticated and unified IPD model is necessary to resolve those existing discrepancies between theoretical and experimental results.However,the applicability of those widely used IPD models nowadays is limited,especially for the nonlocal thermodynamic equilibrium(non-LTE)dense plasma produced by short-pulse laser.In this work,we propose an IPD model that considers inelastic atomic processes,in which three-body recombination and collision ionization processes are found to play a crucial role in determining the electron distribution and IPD for a WDP.This IPD model is validated by reproducing latest experimental results of Al plasmas with a wide-range condition of 70 eV–700 eV temperature and 0.2–3 times solid density,as well as a typical non-LTE system of hollow Al ions.It is demonstrated that the present IPD model has a significant temperature dependence due to the consideration of the inelastic collision processes.With a lower computational cost and wider application range of plasma conditions,the proposed model is expected to provide a promising tool to study the ionization balance and the atomic processes,as well as the related radiation and particle transports properties of the WDP. 展开更多
关键词 properties. COLLISION DETERMINING
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DSAS:A new macromolecular substructure solution program based on the modified phase-retrieval algorithm
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作者 付兴科 谭振希 +2 位作者 耿直 刘茜 丁玮 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第5期125-132,共8页
Considering the pivotal role of single-wavelength anomalous diffraction(SAD) in macromolecular crystallography,our objective was to introduce DSAS,a novel program designed for efficient anomalous scattering substructu... Considering the pivotal role of single-wavelength anomalous diffraction(SAD) in macromolecular crystallography,our objective was to introduce DSAS,a novel program designed for efficient anomalous scattering substructure determination.DSAS stands out with its core components:a modified phase-retrieval algorithm and automated parameter tuning.The software boasts an intuitive graphical user interface(GUI),facilitating seamless input of essential data and real-time monitoring.Extensive testing on DSAS has involved diverse datasets,encompassing proteins,nucleic acids,and various anomalous scatters such as sulfur(S),selenium(Se),metals,and halogens.The results confirm DSAS’s exceptional performance in accurately determining heavy atom positions,making it a highly effective tool in the field. 展开更多
关键词 DSAS single-wavelength anomalous diffraction automated parameters settings phase-retrieval algorithm substructure determination
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TOEPLITZ DETERMINANTS IN ONE AND HIGHER DIMENSIONS
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作者 Surya GIRI S.Sivaprasad KUMAR 《Acta Mathematica Scientia》 SCIE CSCD 2024年第5期1931-1944,共14页
In this study,we derive the sharp bounds of certain Toeplitz determinants whose entries are the coefficients of holomorphic functions belonging to a class defined on the unit disk U.Furthermore,these results are exten... In this study,we derive the sharp bounds of certain Toeplitz determinants whose entries are the coefficients of holomorphic functions belonging to a class defined on the unit disk U.Furthermore,these results are extended to a class of holomorphic functions on the unit ball in a complex Banach space and on the unit polydisc in C^(n).The obtained results provide the bounds of Toeplitz determinants in higher dimensions for various subclasses of normalized univalent functions. 展开更多
关键词 holomorphic mappings starlike mappings Toeplitz determinants coefficient inequalities
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STARLIKENESS ASSOCIATED WITH THE SINE HYPERBOLIC FUNCTION
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作者 Mohsan RAZA Hadiqa ZAHID Jinlin LIU 《Acta Mathematica Scientia》 SCIE CSCD 2024年第4期1244-1270,共27页
Let q_(λ)(z)=1+λsinh(ζ),0<λ<1/sinh(1)be a non-vanishing analytic function in the open unit disk.We introduce a subclass S^(*)(q_(λ))of starlike functions which contains the functions f such that zf'/f i... Let q_(λ)(z)=1+λsinh(ζ),0<λ<1/sinh(1)be a non-vanishing analytic function in the open unit disk.We introduce a subclass S^(*)(q_(λ))of starlike functions which contains the functions f such that zf'/f is subordinated by q_(λ).We establish inclusion and radii results for the class S^(*)(q_(λ))for several known classes of starlike functions.Furthermore,we obtain sharp coefficient bounds and sharp Hankel determinants of order two for the class S^(*)(q_(λ)).We also find a sharp bound for the third Hankel determinant for the caseλ=1/2. 展开更多
关键词 starlike functions sine hyperbolic functions radii problems coefficient bounds Hankel determinants
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Unraveling the regulatory network of flower coloration in soybean:Insights into roles of GmMYBA3 and GmMYBR1
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作者 Ruifang Gao Yueqing Li +8 位作者 Yanan Wang Xiaotong Shan Siqi Yang Ye Zhang Saiyu Ma Chunbao Zhang Jianchun Qin Li Wang Xiang Gao 《The Crop Journal》 SCIE CSCD 2024年第2期443-455,共13页
Anthocyanins play crucial roles in pollen protection and pollinator attraction in flowering plants.However,the mechanisms underlying flower color determination and whether floral anthocyanin regulators participate in ... Anthocyanins play crucial roles in pollen protection and pollinator attraction in flowering plants.However,the mechanisms underlying flower color determination and whether floral anthocyanin regulators participate in other processes remain largely unresolved in soybeans(Glycine max).In this study,we investigated the genetic components and mechanisms governing anthocyanin biosynthesis in soybean flowers.Molecular and genetic studies have characterized two antagonistic regulators,the positive activator GmMYBA3 and the negative repressor GmMYBR1,that modulate the gene expression of anthocyanin biosynthesis in soybean flowers.Further findings revealed a regulatory interplay between GmMYBA3 and GmMYBR1 bridged by GmTT8a,highlighting the complexity of anthocyanin regulation in different soybean organs.Exploration of additional soybean cultivars demonstrated the universality of GmMYBA3 and GmMYBR1 in regulating floral anthocyanin biosynthesis-related genes,with GmF3’5’H identified as a crucial determinant of white flower color.This study provides a molecular mechanism underlying soybean flower color determination,paving the way for the molecular modification of soybean flowers to probably enhance their resistance to abiotic stresses and attractiveness to pollinators. 展开更多
关键词 ANTHOCYANIN Flower color determination MBW complex MYB repressor Pleiotropic regulator
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Influence of O-O formation pathways and charge transfer mediator on lipid bilayer membrane-like photoanodes for water oxidation
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作者 Yingzheng Li Shaoqi Zhan +9 位作者 Zijian Deng Meng Chen Yilong Zhao Chang Liu Ziqi Zhao Hongxia Ning Wenlong Li Fei Li Licheng Sun Fusheng Li 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2024年第6期526-537,I0013,共13页
Inspired by the function of crucial components in photosystemⅡ(PSⅡ),electrochemical and dyesensitized photoelectrochemical(DSPEC)water oxidation devices were constructed by the selfassembly of well-designed amphipat... Inspired by the function of crucial components in photosystemⅡ(PSⅡ),electrochemical and dyesensitized photoelectrochemical(DSPEC)water oxidation devices were constructed by the selfassembly of well-designed amphipathic Ru(bda)-based catalysts(bda=2,2'-bipyrdine-6,6'-dicarbonoxyl acid)and aliphatic chain decorated electrode surfaces,forming lipid bilayer membrane(LBM)-like structures.The Ru(bda)catalysts on electrode-supported LBM films demonstrated remarkable water oxidation performance with different O-O formation mechanisms.However,compared to the slow charge transfer process,the O-O formation pathways did not determine the PEC water oxidation efficiency of the dyesensitized photoanodes,and the different reaction rates for similar catalysts with different catalytic paths did not determine the PEC performance of the DSPECs.Instead,charge transfer plays a decisive role in the PEC water oxidation rate.When an indolo[3,2-b]carbazole derivative was introduced between the Ru(bda)catalysts and aliphatic chain-modified photosensitizer in LBM films,serving as a charge transfer mediator for the tyrosine-histidine pair in PSⅡ,the PEC water oxidation performance of the corresponding photoanodes was dramatically enhanced. 展开更多
关键词 Water oxidation Rate determine step Dye-sensitized photoelectrochemical cell Charge transfer Artificial photosynthesis
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Effects of water and nitrogen rate on grain-filling characteristics under high-low seedbed cultivation in winter wheat
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作者 Junming Liu Zhuanyun Si +6 位作者 Shuang Li Lifeng Wu Yingying Zhang Xiaolei Wu Hui Cao Yang Gao Aiwang Duan 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2024年第12期4018-4031,共14页
A high-efficiency mode of high-low seedbed cultivation(HLSC)has been listed as the main agricultural technology to increase land utilization ratio and grain yield in Shandong Province,China.However,limited information... A high-efficiency mode of high-low seedbed cultivation(HLSC)has been listed as the main agricultural technology to increase land utilization ratio and grain yield in Shandong Province,China.However,limited information is available on the optimized water and nitrogen management for yield formation,especially the grain-filling process,under HLSC mode.A three-year field experiment with four nitrogen rates and three irrigation rates of HLSC was conducted to reveal the response of grain-filling parameters,grain weight percentage of spike weight(GPS),spike moisture content(SMC),and winter wheat yield to water and nitrogen rates.The four nitrogen rates were N1(360 kg ha^(-1) pure N),N2(300 kg ha^(-1) pure N),N3(240 kg ha^(-1) pure N),and N4(180 kg ha^(-1) pure N),respectively,and the three irrigation quotas were W1(120 mm),W2(90 mm),and W3(60 mm),respectively.Results showed that the determinate growth function generally performed well in simulating the temporal dynamics of grain weight(0.989<R^(2)<0.999,where R2 is the determination coefficient).The occurrence time of maximum filling rate(T_(max))and active grain-filling period(AGP)increased with the increase in the water or nitrogen rate,whereas the average grain-filling rate(G_(mean))had a decreasing trend.The final 1,000-grain weight(FTGW)increased and then decreased with the increase in the nitrogen rates and increased with the increase in the irrigation rates.The GPS and SMC had a highly significant quadratic polynomial relationship with grain weight and days after anthesis.Nitrogen,irrigation,and year significantly affected the T_(max),AGP,G_(mean),and FTGW.Particularly,the AGP and FTGW were insignificantly different between high seedbed(HLSC-H)and low seedbed(HLSC-L)across the water and nitrogen levels.Moreover,the moderate water and nitrogen supply was more beneficial for grain yield,as well as for spike number and grain number per hectare.The principal component analysis indicated that combining 240-300 kg N ha^(-1) and 90^(-1)20 mm irrigation quota could improve grain-filling efficiency and yield for the HLSC-cultivated winter wheat. 展开更多
关键词 high-low seedbed cultivation water and nitrogen grain filling determinate growth equation wheat yield
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Cryo-EM combined with image deconvolution to determine ZIF-8 crystal structure
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作者 吴抗 杨柏松 +3 位作者 薛文华 孙大鹏 葛炳辉 王玉梅 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第7期44-49,共6页
Metal–organic frameworks(MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2]It is challenging to visualize MOFs with transmissi... Metal–organic frameworks(MOFs) are crystalline porous materials with tunable properties, exhibiting great potential in gas adsorption, separation and catalysis.[1,2]It is challenging to visualize MOFs with transmission electron microscopy(TEM) due to their inherent instability under electron beam irradiation. Here, we employ cryo-electron microscopy(cryoEM) to capture images of MOF ZIF-8, revealing inverted-space structural information at a resolution of up to about 1.7A and enhancing its critical electron dose to around 20 e^(-)/A^(2). In addition, it is confirmed by electron-beam irradiation experiments that the high voltage could effectively mitigate the radiolysis, and the structure of ZIF-8 is more stable along the [100] direction under electron beam irradiation. Meanwhile, since the high-resolution electron microscope images are modulated by contrast transfer function(CTF) and it is difficult to determine the positions corresponding to the atomic columns directly from the images. We employ image deconvolution to eliminate the impact of CTF and obtain the structural images of ZIF-8. As a result, the heavy atom Zn and the organic imidazole ring within the organic framework can be distinguished from structural images. 展开更多
关键词 cryo-electron microscopy(cryo-EM) ZIF-8 image deconvolution crystal structure determination
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Investigation of sex determination in starry flounder(Platichthys stellatus)reveals sex chromosome evolution in Pleuronectiformes and identifies a sex-specific marker
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作者 Wei-Jing Li Yu-Man Zhang +11 位作者 Shuo Li Yu-Yan Liu Chen Li Sheng-Lei Han Kai-Qiang Liu Lucas Benites Doretto Bing-Hua Liu Hai-Jun Huang Zhi-Long Sun Qian Wang Hong-Yan Wang Chang-Wei Shao 《Zoological Research》 SCIE CSCD 2024年第6期1347-1356,共10页
The identification of sex chromosomes is fundamental for exploring the mechanism and evolution of sex determination.Platichthys stellatus,a species exhibiting clear sexual dimorphism and homomorphic chromosome pairs,h... The identification of sex chromosomes is fundamental for exploring the mechanism and evolution of sex determination.Platichthys stellatus,a species exhibiting clear sexual dimorphism and homomorphic chromosome pairs,has received limited research concerning its sex determination mechanisms.Clarifying the sex chromosome of P.stellatus will enhance our understanding of sex chromosome evolution in Pleuronectiformes.This study employed whole-genome resequencing to investigate the sex chromosome and sex determination system in P.stellatus.Notably,Chr23 was identified as the sex chromosome in P.stellatus,with the sex-determining region(SDR)occupying 48.1%of the chromosome and featuring an XX/XY system.Sex chromosome turnover was observed within Pleuronectiformes,with P.stellatus,Verasper variegatus,and Hippoglossus hippoglossus sharing a common ancestral karyotype.No inversions were detected within the SDR of P.stellatus,although chromosomal rearrangements between sex chromosomes and autosomes were identified.Additionally,a sex-specific marker for P.stellatus was ascertained,enabling genetic sex identification,with significant implications for improving breeding programs and aquaculture practices. 展开更多
关键词 Sex chromosome Platichthys stellatus Sex determination system Ancestral karyotype of Pleuronectiformes Sex-specific marker
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On a special type of Ma-Minda function
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作者 S.Sivaprasad Kumar Shagun Banga 《Applied Mathematics(A Journal of Chinese Universities)》 SCIE CSCD 2024年第4期654-673,共20页
We introduce a primitive class of analytic functions, by specializing in many wellknown classes, classify Ma-Minda functions based on its conditions and their interesting geometrical aspects. Further, study a newly de... We introduce a primitive class of analytic functions, by specializing in many wellknown classes, classify Ma-Minda functions based on its conditions and their interesting geometrical aspects. Further, study a newly defined subclass of starlike functions involving a special type of Ma-Minda function introduced here for obtaining inclusion and radius results. We also establish some majorization, Bloch function norms, and other related problems for the same class. 展开更多
关键词 Ma-Minda function typically real function Hankel determinants sharp coefficient bounds radius problems logarithmic function
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Relative orbit determination algorithm of space targets with passive observation
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作者 DAI Chenchao QIANG Hongfu +2 位作者 ZHANG Degang HU Shaolei GONG Baichun 《Journal of Systems Engineering and Electronics》 SCIE CSCD 2024年第3期793-804,共12页
Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for ang... Angles-only relative orbit determination for space non-cooperative targets based on passive sensor is subject to weakly observable problem of the relative state between two spacecraft. Previously, the evidence for angles-only observability was found by using cylindrical dynamics, however, the solution of orbit determination is still not provided. This study develops a relative orbit determination algorithm with the cylindrical dynamics based on differential evolution. Firstly, the relative motion dynamics and line-of-sight measurement model for nearcircular orbit are established in cylindrical coordinate system.Secondly, the observability is qualitatively analyzed by using the dynamics and measurement model where the unobservable geometry is found. Then, the angles-only relative orbit determination problem is modeled into an optimal searching frame and an improved differential evolution algorithm is introduced to solve the problem. Finally, the proposed algorithm is verified and tested by a set of numerical simulations in the context of highEarth and low-Earth cases. The results show that initial relative orbit determination(IROD) solution with an appropriate accuracy in a relative short span is achieved, which can be used to initialize the navigation filter. 展开更多
关键词 angles-only measurement relative orbit determination cylindrical coordinate differential evolution
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Evaluating the relative importance of predictors in Generalized Additive Models using the gam.hp R package
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作者 Jiangshan Lai Jing Tang +2 位作者 Tingyuan Li Aiying Zhang Lingfeng Mao 《Plant Diversity》 SCIE CAS CSCD 2024年第4期542-546,共5页
Generalized Additive Models(GAMs)are widely employed in ecological research,serving as a powerful tool for ecologists to explore complex nonlinear relationships between a response variable and predictors.Nevertheless,... Generalized Additive Models(GAMs)are widely employed in ecological research,serving as a powerful tool for ecologists to explore complex nonlinear relationships between a response variable and predictors.Nevertheless,evaluating the relative importance of predictors with concurvity(analogous to collinearity)on response variables in GAMs remains a challenge.To address this challenge,we developed an R package named gam.hp.gam.hp calculates individual R^(2) values for predictors,based on the concept of'average shared variance',a method previously introduced for multiple regression and canonical analyses.Through these individual R^(2)s,which add up to the overall R^(2),researchers can evaluate the relative importance of each predictor within GAMs.We illustrate the utility of the gam.hp package by evaluating the relative importance of emission sources and meteorological factors in explaining ozone concentration variability in air quality data from London,UK.We believe that the gam.hp package will improve the interpretation of results obtained from GAMs. 展开更多
关键词 Average shared variance Coefficient of determination Commonality analysis GAMs Hierarchical partitioning Individual R^(2)
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Overexpression of Kdm6b induces testicular differentiation in a temperature-dependent sex determination system
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作者 Qiran Chen Wei Sun +3 位作者 Lin Jin Yingjie Zhou Fang Li Chutian Ge 《Zoological Research》 SCIE CSCD 2024年第5期1108-1115,共8页
In reptiles,such as the red-eared slider turtle(Trachemys scripta elegans),gonadal sex determination is highly dependent on the environmental temperature during embryonic stages.This complex process,which leads to dif... In reptiles,such as the red-eared slider turtle(Trachemys scripta elegans),gonadal sex determination is highly dependent on the environmental temperature during embryonic stages.This complex process,which leads to differentiation into either testes or ovaries,is governed by the finely tuned expression of upstream genes,notably the testis-promoting gene Dmrt1 and the ovary-promoting gene Foxl2.Recent studies have identified epigenetic regulation as a crucial factor in testis development,with the H3K27me3 demethylase KDM6B being essential for Dmrt1 expression in T.s.elegans.However,whether KDM6B alone can induce testicular differentiation remains unclear.In this study,we found that overexpression of Kdm6b in T.s.elegans embryos induced the male development pathway,accompanied by a rapid increase in the gonadal expression of Dmrt1 at 31°C,a temperature typically resulting in female development.Notably,this sex reversal could be entirely rescued by Dmrt1 knockdown.These findings demonstrate that Kdm6b is sufficient for commitment to the male pathway,underscoring its role as a critical epigenetic regulator in the sex determination of the red-eared slider turtle. 展开更多
关键词 Temperature-dependent sex determination Sex reversal Kdm6b DMRT1 T.s.elegans
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