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Preliminary study on a quantification method and standardization for aquatic microbial loads based on microbial diversity absolute quantitative sequencing
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作者 Wen Li Jing Libin +4 位作者 Li Xiawei Lu Jing Jin Haowei Yang Yongqi Li Xueling 《China Standardization》 2026年第1期68-73,共6页
This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from... This study establishes and validates a method for the precise quantification of aquatic microbial loads using microbial diversity absolute quantitative sequencing.By adding synthetic spike-in DNA to water samples from the Dahei River prior to DNA extraction and 16S rRNA gene sequencing,it generates standard curves to convert sequencing data into absolute microbial copy numbers.The method,which is proved highly accurate(R^(2)>0.99),reveals a clear contrast between the river sites:the upstream community has not only a significantly higher total microbial load but also a completely different makeup of species compared to the downstream site.This approach effectively overcomes the limitations of relative abundance analysis,providing a powerful tool for environmental monitoring,and proposes key steps for future standardization to ensure data comparability and integration. 展开更多
关键词 absolute quantification microbial load 16S rRNA sequencing spike-in STANDARDIZATION aquatic microbes
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Revision of the absolute configurations of Pallavicinia diterpenoids and further discovery of their Diels-Alder cycloadducts
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作者 Jiao-Zhen Zhang Cheng-Min Zhang +7 位作者 Yong-Jie Wang Pei-Lin Wu Rui-Feng Liu Ye Li Ming-Zhu Zhu Shuang-Zhi Yuan Ze-Jun Xu Hong-Xiang Lou 《Chinese Chemical Letters》 2026年第1期394-398,共5页
Owing to their intricate molecular frameworks and copious chiral centers,the structural identification and configurational assignment of natural products are challenging tasks.Comprehensive spectral data analysis is c... Owing to their intricate molecular frameworks and copious chiral centers,the structural identification and configurational assignment of natural products are challenging tasks.Comprehensive spectral data analysis is crucial for the confirmation of absolute configurations.Ignoring critical parameters will lead to false structure,which may confuse the total synthesis and drug development.Herein,the configurations of seven heterogeneous Pallavicinia diterpenoids(PDs) isolated from Pallavicinia liverworts are revised using a combination of single-crystal X-ray diffraction and electronic circular dichroism(ECD) calculations.Meanwhile,identification of five unprecedented PD heterodimers PD-dimers A-E(18-22) along with eleven previously undescribed PDs(5-9,13-17,23) obtained by the reinvestigation of the Chinese liverwort Pallavicinia subciliata have resulted in corrections and support the revised conclusions. 展开更多
关键词 REVISION absolute configurations Pallavicinia diterpenoids LIVERWORT Single-crystal X-ray diffraction Electronic circular dichroism calculations
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Comprehensive Analysis of the Relative Dispersion of Droplet-Size Distributions and Their Relationships to Key Physical Fog Processes Under Different Aerosol Conditions and Evolutionary Stages
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作者 Xingcan JIA Chunsong LU +7 位作者 Zhiheng LIAO Ping TIAN Yuan WANG Fei WANG Shuai YANG Youjun DOU Xiange LIU Yangang LIU 《Advances in Atmospheric Sciences》 2026年第4期861-873,I0042-I0046,共18页
The relative dispersion of cloud and fog droplets has significant impacts on aerosol indirect effects,radiative transfer,and microphysical processes.However,previous studies have been mostly concerned with clouds,with... The relative dispersion of cloud and fog droplets has significant impacts on aerosol indirect effects,radiative transfer,and microphysical processes.However,previous studies have been mostly concerned with clouds,with limited studies on fog,particularly those that examine the combined influences of all key physical processes and their roles during fog evolution.As such,this study aims to conduct a comprehensive investigation by examining the relationships between relative dispersion and other microphysical variables,as well as the underlying microphysical and dynamic processes,based on field fog campaigns in polluted and clean conditions.In polluted fog,droplet concentrations are higher,leading to smaller droplets and increased dispersion.The correlation between dispersion and droplet volume-mean radius is positive in the polluted fog,but shifts to negative in clean fog.We attribute the difference to various microphysical processes like aerosol activation,condensation,collision-coalescence,and entrainment-mixing.In polluted fog,high aerosol concentrations,low supersaturations,and strong turbulence(entrainment-mixing)provide suitable conditions for the simultaneous occurrence of droplet condensation and aerosol activation,resulting in a positive correlation between dispersion and volume-mean radius,especially during the fog formation stage.In contrast,during the mature stage in clean fog,condensation is dominant with weak aerosol activation leading to a negative correlation between relative dispersion and volume-mean radius.The collision-coalescence process is more active in the mature stage,increasing radii and leading to the negative correlation between dispersion and volume-mean radius.This result sheds new light on understanding the relative dispersion and mechanisms in fog under different aerosol backgrounds. 展开更多
关键词 FOG relative dispersion evolutionary stage aerosol activation collision-coalescence
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Monotonic triaxial testing and hypoplastic modelling of calcareous sand:A focus on particle breakage and initial relative density
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作者 Jiarui Chen Yaolan Tang +4 位作者 Shun Wang Chunshun Zhang Wei Wei Jie Dong Congying Li 《Journal of Rock Mechanics and Geotechnical Engineering》 2026年第2期1504-1525,共22页
The stress-strain behavior of calcareous sand is significantly influencedby particle breakage(B)and initial relative density(Dri),but few constitutive models consider their combined effects.To bridge this gap,we condu... The stress-strain behavior of calcareous sand is significantly influencedby particle breakage(B)and initial relative density(Dri),but few constitutive models consider their combined effects.To bridge this gap,we conducted a series of triaxial tests on calcareous sand with varying Dri and stress paths,examining particle breakage and critical state behavior.Key findingsinclude:(1)At a constant stress ratio(η),B follows a hyperbolic relationship with mean effective stress(p'),and for a given p',B increases proportionally withη;(2)The critical state line(CSL)moves downward with increasing Dri,whereas the critical state friction angle(φcs)decreases with increasing B.Based on these findings,we propose a unifiedbreakage evolution model to quantify particle breakage in calcareous sand under various loading conditions.Integrating this model with the Normal Consolidation Line(NCL)and CSL equations,we successfully simulate the steepening of NCL and CSL slopes as B increases with the onset of particle breakage.Furthermore,we quantitatively evaluate the effect of B onφcs.Finally,within the framework of Critical State Soil Mechanics and Hypoplasticity theory,we develop a hypoplastic model incorporating B and Dri.The model is validated through strong agreement with experimental results across various initial relative densities,stress paths and drainage conditions. 展开更多
关键词 Calcareous sand Constitutive model HYPOPLASTICITY Particle breakage Initial relative density Triaxial test
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Quantitative analysis of the relative tectonic activity of the Almus fault zone,Tokat,Türkiye
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作者 Serkan GÜRGÖZE 《Journal of Mountain Science》 2026年第1期29-48,共20页
The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents t... The Almus Fault Zone(AFZ)is one of the major splay faults of the North Anatolian Fault Zone(NAFZ)and is important for understanding its tectonic features and assessing regional seismic hazards.This research presents the integration of morphometric indices to quantitatively assess the spatial variation of tectonic activity along the AFZ.The AFZ is an active fault with both strike-slip and normal fault components and consists of two main branches,Mercimekdağı-Çamdere Fault(MÇF)and Tokat Fault(TF)segments.This study aims to assess the relative tectonic activity of the AFZ using various morphometric indices,based on a 10 m resolution DEM,with the aid of ArcGIS and MATLAB software.For this purpose,morphometric indices such as hypsometric integral(HI:0.35-0.65),mountain front sinuosity(Smf:1.3-1.44),valley floor width-height ratio(Vf:0.15-2.28),asymmetry factor(AF:23-77),drainage basin shape(Bs:1.13-6.10)and normalized steepness index(ksn:1-498)were applied to 53 drainage basins.When the Smf and mean Vf indices results were evaluated,it was calculated that the uplift ratio of the region was more than 0.5 mm/yr.The spatial distribution of the relative tectonic activity(Iat)of the area was revealed by combining the obtained morphometric indices analysis results.According to the Iat result,it was concluded that the MercimekdağıÇamdere Fault and Tokat Fault segments have high tectonic activity,but the Mercimekdağı-Çamdere Fault segment has higher tectonic activity.The results obtained were also confirmed by field observations.This research provides valuable information for the evaluation of tectonic activity in drainage systems controlled by splay faults. 展开更多
关键词 Almus Fault Zone Morphometric indices relative tectonic activity Tokat Türkiye
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Effect of initial temperature and relative humidity on VHP penetration during HEPA in-situ fumigation disinfection
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作者 Ye Yuan Jiajing Sui Xiangfei Kong 《Energy and Built Environment》 2026年第1期1-13,共13页
The high efficiency particulate air filter(HEPA)in exhaust system of high-level biosafety laboratory must be disinfected to kill harmful microorganisms before being replaced or tested.In-situ fumigation by vaporized h... The high efficiency particulate air filter(HEPA)in exhaust system of high-level biosafety laboratory must be disinfected to kill harmful microorganisms before being replaced or tested.In-situ fumigation by vaporized hydrogen peroxide(VHP)is the most commonly used disinfection method for HEPA unit.The disinfection effect of HEPA unit is affected by the internal environment,but the influence of initial internal environment on VHP penetration during the fumigation process is still rarely studied.In this paper,a numerical model was established based on a physical HEPA box unit and field measurement.According to the simulated VHP flow field during in-situ fumigation process,the influence of initial internal temperature and relative humidity on the VHP penetration effect in HEPA was discussed with the indicators of penetration rate and velocity distribution.The results showed that the VHP concentration in the upstream section of HEPA was relatively uniform,while the maximum and minimum concentrations in the downstream section showed great difference and located at the top and bottom,respectively.The distributions of VHP penetration and upstream velocity were both vertically uneven.The VHP penetration rates in the middle of HEPA remained around 73%.The initial temperature of 32℃or 36℃,or the initial relative humidity of 18%were the suitable initial internal environment for HEPA in-situ fumigation,which could keep the VHP penetration rates of the upper and lower parts of HEPA at about 76%and 61%,respectively.In the suitable initial environment,the penetration and disinfection effect could be promoted by appropriately extending the rapid injection duration.This study provides a reference for optimizing the initial environment setting of HEPA in-situ fumigation. 展开更多
关键词 Initial temperature and relative humidity High efficiency particulate air filter Fumigation disinfection Vaporized hydrogen peroxide Penetration effect
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Relative Motion Based Predictive Adaptive Control:A Case Study of AUV 3D Trajectory Tracking
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作者 Daxiong Ji Xinwei Wang Yuanchang Liu 《IEEE/CAA Journal of Automatica Sinica》 2026年第2期492-494,共3页
Dear Editor,This letter deals with the autonomous underwater vehicle(AUV)three dimensional(3D)trajectory tracking control chronically suffering from poor accuracy and efficiency in complex hydrodynamics.A state-of-the... Dear Editor,This letter deals with the autonomous underwater vehicle(AUV)three dimensional(3D)trajectory tracking control chronically suffering from poor accuracy and efficiency in complex hydrodynamics.A state-of-the-art predictive adaptive controller(PAC)is proposed with a distinct dual closed-loop structure. 展开更多
关键词 adaptive controller pac autonomous underwater vehicle auv three predictive adaptive control relative motion D trajectory tracking HYDRODYNAMICS closed loop structure complex hydrodynamicsa
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Identification of protein targets for the antidepressant effects of Kai-Xin-San in Chinese medicine using isobaric tags for relative and absolute quantitation 被引量:5
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作者 Xian-Zhe Dong Dong-Xiao Wang +3 位作者 Tian-Yi Zhang Xu Liu Ping Liu Yuan Hu 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第2期302-310,共9页
Kai-Xin-San consists of Ginseng Radix, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria at a ratio of 3:3:2:2. Kai-Xin-San has been widely used for the treatment of emotional disorders in China. However, no studi... Kai-Xin-San consists of Ginseng Radix, Polygalae Radix, Acori Tatarinowii Rhizoma, and Poria at a ratio of 3:3:2:2. Kai-Xin-San has been widely used for the treatment of emotional disorders in China. However, no studies have identified the key proteins implicated in response to Kai-Xin-San treatment. In this study, rat models of chronic mild stress were established using different stress methods over 28 days. After 14 days of stress stimulation, rats received daily intragastric administrations of 600 mg/kg Kai-Xin-San. The sucrose preference test was used to determine depression-like behavior in rats, while isobaric tags were used for relative and absolute quantitation-based proteomics to identify altered proteins following Kai-Xin-San treatment. Kai-Xin-San treatment for 2 weeks noticeably improved depression-like behaviors in rats with chronic mild stress. We identified 33 differentially expressed proteins: 7 were upregulated and 26 were downregulated. Functional analysis showed that these differentially expressed proteins participate in synaptic plasticity, neurodevelopment, and neurogenesis. Our results indicate that Kai-Xin-San has an important role in regulating the key node proteins in the synaptic signaling network, and are helpful to better understand the mechanism of the antidepressive effects of Kai-Xin-San and to provide objective theoretical support for its clinical application. The study was approved by the Ethics Committee for Animal Research from the Chinese PLA General Hospital(approval No. X5-2016-07) on March 5, 2016. 展开更多
关键词 BRAIN-DERIVED neurotrophic factor signal pathway depression ISOBARIC tags for relative and absolute quantitation Kai-Xin-San neurogenesis protein network proteomics analysis synaptic plasticity traditional Chinese medicine
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Different protein expression patterns in rat spinal nerves during wallerian degeneration assessed using isobaric tags for relative and absolute quantitation proteomics profiling 被引量:3
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作者 Shuai Wei Xue-Zhen Liang +12 位作者 Qian Hu Wei-Shan Wang Wen-Jing Xu Xiao-Qing Cheng Jiang Peng Quan-Yi Guo Shu-Yun Liu Wen Jiang Xiao Ding Gong-Hai Han Ping Liu Chen-Hui Shi Yu Wang 《Neural Regeneration Research》 SCIE CAS CSCD 2020年第2期315-323,共9页
Sensory and motor nerve fibers of peripheral nerves have different anatomies and regeneration functions after injury. To gain a clear understanding of the biological processes behind these differences, we used a label... Sensory and motor nerve fibers of peripheral nerves have different anatomies and regeneration functions after injury. To gain a clear understanding of the biological processes behind these differences, we used a labeling technique termed isobaric tags for relative and absolute quantitation to investigate the protein profiles of spinal nerve tissues from Sprague-Dawley rats. In response to Wallerian degeneration, a total of 626 proteins were screened in sensory nerves, of which 368 were upregulated and 258 were downregulated. In addition, 637 proteins were screened in motor nerves, of which 372 were upregulated and 265 were downregulated. All identified proteins were analyzed using the Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis of bioinformatics, and the presence of several key proteins closely related to Wallerian degeneration were tested and verified using quantitative real-time polymerase chain reaction analyses. The differentially expressed proteins only identified in the sensory nerves were mainly relevant to various biological processes that included cell-cell adhesion, carbohydrate metabolic processes and cell adhesion, whereas differentially expressed proteins only identified in the motor nerves were mainly relevant to biological processes associated with the glycolytic process, cell redox homeostasis, and protein folding. In the aspect of the cellular component, the differentially expressed proteins in the sensory and motor nerves were commonly related to extracellular exosomes, the myelin sheath, and focal adhesion. According to the Kyoto Encyclopedia of Genes and Genomes, the differentially expressed proteins identified are primarily related to various types of metabolic pathways. In conclusion, the present study screened differentially expressed proteins to reveal more about the differences and similarities between sensory and motor nerves during Wallerian degeneration. The present findings could provide a reference point for a future investigation into the differences between sensory and motor nerves in Wallerian degeneration and the characteristics of peripheral nerve regeneration. The study was approved by the Ethics Committee of the Chinese PLA General Hospital, China(approval No. 2016-x9-07) in September 2016. 展开更多
关键词 gene ontology Kyoto ENCYCLOPEDIA of Genes and Genomes ISOBARIC tags for relative and absolute quantitation motor NERVE PROTEOMICS sensory NERVE spinal NERVE Wallerian degeneration
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Estimation of peak relative velocity and peak absolute acceleration of linear SDOF systems 被引量:3
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作者 Jianwei Song Yi-Lun Chu Zach Liang George C. Lee 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第1期1-10,共10页
In the seismic analysis and design of structures, the true velocity and absolute acceleration are usually approximated by their corresponding pseudo-values. This approach is simple and works well for structures with s... In the seismic analysis and design of structures, the true velocity and absolute acceleration are usually approximated by their corresponding pseudo-values. This approach is simple and works well for structures with small damping (say, less than 15%). When the damping of a structure is enhanced for the purpose of response reduction, it may result in large analysis and design errors. Based on theory of random vibration and the established mechanism of seismic response spectra analysis, a method is developed (1) to predict the relative velocity spectra with any damping ratio level directly from the 5% standard pseudo-acceleration spectrum; and (2) to estimate the peak absolute acceleration. The accuracy of both is validated by using two selected ensembles of ground motion records. 展开更多
关键词 damping device velocity spectrum absolute acceleration spectrum response spectrum analysis
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Serum proteins differentially expressed in gestational diabetes mellitus assessed using isobaric tag for relative and absolute quantitation proteomics 被引量:4
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作者 Wei-Li Cao Cui-Ping Yu Ling-Li Zhang 《World Journal of Clinical Cases》 SCIE 2024年第8期1395-1405,共11页
BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients a... BACKGROUND As a well-known fact to the public,gestational diabetes mellitus(GDM)could bring serious risks for both pregnant women and infants.During this important investigation into the linkage between GDM patients and their altered expression in the serum,proteomics techniques were deployed to detect the differentially expressed proteins(DEPs)of in the serum of GDM patients to further explore its pathogenesis,and find out possible biomarkers to forecast GDM occurrence.METHODS Subjects were divided into GDM and normal control groups according to the IADPSG diagnostic criteria.Serum samples were randomly selected from four cases in each group at 24-28 wk of gestation,and the blood samples were identified by applying iTRAQ technology combined with liquid chromatography-tandem mass spectrometry.Key proteins and signaling pathways associated with GDM were identified by bioinformatics analysis,and the expression of key proteins in serum from 12 wk to 16 wk of gestation was further verified using enzyme-linked immunosorbent assay (ELISA).RESULTS Forty-seven proteins were significantly differentially expressed by analyzing the serum samples between the GDMgravidas as well as the healthy ones. Among them, 31 proteins were found to be upregulated notably and the rest16 proteins were downregulated remarkably. Bioinformatic data report revealed abnormal expression of proteinsassociated with lipid metabolism, coagulation cascade activation, complement system and inflammatory responsein the GDM group. ELISA results showed that the contents of RBP4, as well as ANGPTL8, increased in the serumof GDM gravidas compared with the healthy ones, and this change was found to initiate from 12 wk to 16 wk ofgestation.CONCLUSION GDM symptoms may involve abnormalities in lipid metabolism, coagulation cascade activation, complementsystem and inflammatory response. RBP4 and ANGPTL8 are expected to be early predictors of GDM. 展开更多
关键词 Gestational diabetes mellitus Liquid chromatography-tandem mass spectrometry Isobaric tag for relative and absolute quantitation PROTEOMICS BIOMARKER
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Estimation of peak relative velocity and peak absolute acceleration of linear SDOF systems 被引量:1
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作者 George C. Lee 《Earthquake Engineering and Engineering Vibration》 SCIE EI CSCD 2007年第2期213-213,共1页
We have found some mistakes in the article by Jianwei Song et al. (2007). The revisions are given below:
关键词 SDOF Estimation of peak relative velocity and peak absolute acceleration of linear SDOF systems
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Soil Carbon Dynamics Under Changing Climate A Research Transition from Absolute to Relative Roles of Inorganic Nitrogen Pools and Associated Microbial Processes:A Review 被引量:6
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作者 pratap srivastava rishikesh singh +5 位作者 sachchidanand tripathi pardeep singh shikha singh hema singh akhilesh singh raghubanshi pradeep kumar mishra 《Pedosphere》 SCIE CAS CSCD 2017年第5期792-806,共15页
It is globally accepted that soil carbon (C) dynamics are at the core of interlinked environmental problems, deteriorating soil quality and changing climate. Its management remains a complex enigma for the scientifi... It is globally accepted that soil carbon (C) dynamics are at the core of interlinked environmental problems, deteriorating soil quality and changing climate. Its management remains a complex enigma for the scientific community due to its intricate relationship with soil nitrogen (N) availability and moisture-temperature interactions. This article reviews the management aspects of soil C dynamics in light of recent advances, particularly in relation to the availability of inorganic N pools and associated microbial processes under changing climate. Globally, drastic alterations in soil C dynamics under changing land use and management practices have been primarily attributed to the variation in soil N availability, resulting in a higher decomposition rate and a considerable decline in soil organic C (SOC) levels due to increased soil CO2 emissions, degraded soil quality, and increased atmospheric CO2 concentrations, leading to climate warming. Predicted climate warming is proposed to enhance SOC decomposition, which may further increase soil N availability, leading to higher soil CO2 effiux. However, a literature survey revealed that soil may also act as a potential C sink, if we could manage soil inorganic N pools and link microbial processes properly. Studies also indicated that the relative, rather than the absolute, availability of inorganic N pools might be of key importance under changing climate, as these N pools are variably affected by moisture-temperature interactions, and they have variable impacts on SOC turnover. Therefore, multi-factorial studies are required to understand how the relative availability of inorganic N pools and associated microbial processes may determine SOC dynamics for improved soil C management. 展开更多
关键词 agro-management IMMOBILIZATION NH4+-N to NO3-N ratio NITRIFICATION relative availability soil C02 effiux
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Super Antibiotics, Part IV. Hyperforin, Relative and Absolute Stereochemistry Elucidated by Gas-Chromatography Mass-Spectrometry with Supersonic Molecular Beams
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作者 Ilia Brondz 《International Journal of Analytical Mass Spectrometry and Chromatography》 2017年第3期70-85,共16页
Relative and absolute stereochemistry for hyperforin has been proposed by Brondz et al. was supported and new isomer of hyperforin-perforatrin has been discovered. Relative and absolute stereochemistry for perforatrin... Relative and absolute stereochemistry for hyperforin has been proposed by Brondz et al. was supported and new isomer of hyperforin-perforatrin has been discovered. Relative and absolute stereochemistry for perforatrin was proposed and elucidated by using gas-chromatography mass-spectrometry with supersonic molecular beams (SMB). The possibility of the existence of ambiguities in chirality as a hypothesis for the existence, and a new understanding, of chiral substances with shifting chirality is presented. 展开更多
关键词 HYPERFORIN Perforatrin relative and absolute STEREOCHEMISTRY Gas Chromatography-Mass SPECTROMETRY CHIRALITY
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A New Vectorial Order Approach Based on the Classification of Tuples Attribute and Relative Absolute Adaptive Referent: Applications to Multicomponent Images
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作者 Adles Francis Kouassi Sié Ouattara +4 位作者 Jean-Claude Okaingni Adama Koné Wognin Joseph Vangah Georges Loum Alain Clement 《Journal of Software Engineering and Applications》 2017年第6期546-563,共18页
In this paper, we are presenting a new vector order, a solution to the open problem of the generalization of mathematical morphology to multicomponent images and multidimensional data. This approach uses the paradigm ... In this paper, we are presenting a new vector order, a solution to the open problem of the generalization of mathematical morphology to multicomponent images and multidimensional data. This approach uses the paradigm of P–order. Its primary principle consists, first in partitioning the multi-component image in the attribute space by a classification method in different numbers of classes, and then the vector attributes are ordered within each class (intra-order-class). And finally the classes themselves are ordered in turn from their barycenter (inter-class order). Thus, two attribute vectors (or colors) whatever, belonging to the vector image can be compared. Provided with this relation of order, vectors attributes of a multivariate image define a complete lattice ingredient necessary for the definition of the various morphological operators. In fact, this method creates a strong close similarity between vectors in order to move towards an order of the same principle as defined in the set of real numbers. The more the number of classes increases, the more the colors of the same class are similar and therefore the absolute adaptive referent tends to be optimal. On the other hand, the more the class number decreases or equals two, the more our approach tends towards the hybrid order developed previously. The proposed order has been implemented on different morphological operators through different multicomponent images. The fundamental robustness of our approach and that relating to noise have been tested. The results on the gradient, Laplacian and Median filter operators show the performance of our new order. 展开更多
关键词 MULTICOMPONENT Image P-Order Optima ADAPTIVE absolute REFERENT Intraclass and Interclass Order Morphological Operators Noise
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Distribution,species richness,and relative importance of different plant life forms across drylands in China 被引量:2
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作者 Shuran Yao Weigang Hu +16 位作者 Mingfei Ji Abraham Allan Degen Qiajun Du Muhammad Adnan Akram Yuan Sun Ying Sun Yan Deng Longwei Dong Haiyang Gong Qingqing Hou Shubin Xie Xiaoting Wang Jinzhi Ran Bernhard Schmid Qinfeng Guo Karl J.Niklas Jianming Deng 《Plant Diversity》 2025年第2期273-281,共9页
Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmen... Studies on plant diversity are usually based on the total number of species in a community.However,few studies have examined species richness(SR)of different plant life forms in a community along largescale environmental gradients.Particularly,the relative importance(RIV)of different plant life forms in a community and how they vary with environmental variables are still unclear.To fill these gaps,we determined plant diversity of ephemeral plants,annual herbs,perennial herbs,and woody plants from 187 sites across drylands in China.The SR patterns of herbaceous plants,especially perennial herbs,and their RIV in plant communities increased with increasing precipitation and soil nutrient content;however,the RIV of annual herbs was not altered along these gradients.The SR and RIV of ephemeral plants were affected mainly by precipitation seasonality.The SR of woody plants had a unimodal relationship with air temperature and exhibited the highest RIV and SR percentage in plant communities under the harshest environments.An obvious shift emerged in plant community composition,SR and their critical impact factors at 238.5 mm of mean annual precipitation(MAP).In mesic regions(>238.5 mm),herbs were the dominant species,and the SR displayed a relatively slow decreasing rate with increasing aridity,which was mediated mainly by MAP and soil nutrients.In arid regions(<238.5 mm),woody plants were the dominant species,and the SR displayed a relatively fast decreasing rate with increasing aridity,which was mediated mainly by climate variables,especially precipitation.Our findings highlight the importance of comparative life form studies in community structure and biodiversity,as their responses to gradients differed substantially on a large scale. 展开更多
关键词 DRYLANDS Environmental gradients Plant life forms relative importance Species richness THRESHOLD
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ENGINet:End-to-end deep learning of the cumulative absolute velocity,Arias intensity,and spectrum intensity prediction for on-site earthquake early warning 被引量:1
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作者 Zhu Jingbao Li Shanyou Song Jindong 《Earthquake Engineering and Engineering Vibration》 2025年第4期943-957,I0002-I0096,共110页
One of the primary tasks of earthquake early warning(EEW)systems is to predict potential earthquake damage rapidly and accurately.Cumulative absolute velocity(CAV),Arias intensity(I_(A)),and spectrum intensity(SI)are ... One of the primary tasks of earthquake early warning(EEW)systems is to predict potential earthquake damage rapidly and accurately.Cumulative absolute velocity(CAV),Arias intensity(I_(A)),and spectrum intensity(SI)are important parameters for measuring ground motion intensity and assessing earthquake damage.Due to the limited available information in EEW,CAV,I_(A),and SI cannot be accurately predicted using traditional EEW methods.In this paper,we propose an end-to-end deep learning-based Ground motion Intensity prediction Network(ENGINet)for on-site EEW.The aim of the ENGINet is to predict CAV,I_(A),and SI rapidly and reliably.ENGINet is based on a convolutional neural network and recurrent neural network.The inputs of the network are three-component acceleration records,three-component velocity records,and three-component displacement records obtained by a single station.The results from the test dataset show that at 3 s after the P-wave arrival,compared with the baseline models and other traditional methods,ENGINet has better performance in predicting CAV,I_(A),and SI.Our results indicate that ENGINet can quickly and accurately predict CAV,I_(A),and SI to some extent and has good potential in EEW efforts. 展开更多
关键词 on-site earthquake early warning deep learning cumulative absolute velocity arias intensity spectrum intensity
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Relative vacuum reduction innovative processes applied in primary magnesium production-Comprehensive analysis of thermodynamics,resource,energy flow,and carbon emission 被引量:2
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作者 Xiaolong Li Tingan Zhang +3 位作者 Yan Liu Junhua Guo Jingzhong Xu Yuanyuan Liang 《Journal of Magnesium and Alloys》 2025年第7期3134-3149,共16页
Magnesium and magnesium alloys,serving as crucial lightweight structural materials and hydrogen storage elements,find extensive applications in space technology,aviation,automotive,and magnesium-based hydrogen industr... Magnesium and magnesium alloys,serving as crucial lightweight structural materials and hydrogen storage elements,find extensive applications in space technology,aviation,automotive,and magnesium-based hydrogen industries.The global production of primary magnesium has reached approximately 1.2 million tons per year,with anticipated diversification in future applications and significant market demand.Nevertheless,approximately 80%of the world’s primary magnesium is still manufactured through the Pidgeon process,grappling with formidable issues including high energy consumption,massive carbon emission,significant resource depletion,and environmental pollution.The implementation of the relative vacuum method shows potential in breaking through technological challenges in the Pidgeon process,facilitating clean,low-carbon continuous magnesium smelting.This paper begins by introducing the principles of the relative vacuum method.Subsequently,it elucidates various innovative process routes,including relative vacuum ferrosilicon reduction,aluminum thermal reduction co-production of spinel,and aluminum thermal reduction co-production of calcium aluminate.Finally,and thermodynamic foundations of the relative vacuum,a quantitative analysis of the material,energy flows,carbon emission,and production cost for several new processes is conducted,comparing and analyzing them against the Pidgeon process.The study findings reveal that,with identical raw materials,the relative vacuum silicon thermal reduction process significantly decreases raw material consumption,energy consumption,and carbon dioxide emissions by 15.86%,30.89%,and 26.27%,respectively,compared to the Pidgeon process.The relative vacuum process,using magnesite as the raw material and aluminum as the reducing agent,has the lowest magnesium-to-feed ratio,at only 3.385.Additionally,its energy consumption and carbon dioxide emissions are the lowest,at 1.817 tce/t Mg and 7.782 t CO_(2)/t Mg,respectively.The energy consumption and carbon emissions of the relative vacuum magnesium smelting process co-producing calcium aluminate(12CaO·7Al_(2)O_(3),3CaO·Al_(2)O_(3),and CaO·Al_(2)O_(3))are highly correlated with the consumption of dolomite in the raw materials.When the reduction temperature is around 1473.15 K,the critical volume fraction of magnesium vapor for different processes varies within the range of 5%–40%.Production cost analysis shows that the relative vacuum primary magnesium smelting process has significant economic benefits.This paper offers essential data support and theoretical guidance for achieving energy efficiency,carbon reduction in magnesium smelting,and the industrial adoption of innovative processes. 展开更多
关键词 Magnesium smelting relative vacuum reduction process THERMODYNAMICS Resource and energy flow Carbon emission
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Study on the condensation behavior of magnesium vapor by flow field disturbance under relative vacuum 被引量:1
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作者 Jing-zhong Xu Ting-an Zhang Hong-xuan Liu 《Journal of Magnesium and Alloys》 2025年第3期1116-1132,共17页
Compared with Pidgeon process,the relative vacuum continuous magnesium smelting process reduces the ratio of material to magnesium by changing raw materials and the direct reduction after calcination of prefabricated ... Compared with Pidgeon process,the relative vacuum continuous magnesium smelting process reduces the ratio of material to magnesium by changing raw materials and the direct reduction after calcination of prefabricated pellets,so that the energy consumption per ton of magnesium produced is reduced by 30∼40%,and the carbon emission is reduced by 43∼52%,breaking through the vacuum conditions to achieve continuous production.However,in the process of industrialization,it was found that the magnesium yield in the condenser was low.Therefore,this paper constructs a condenser model of relative vacuum continuous magnesium refining process,and comprehensively analyzes the condensation mechanism of magnesium vapor through simulation and experiment.It is found that the dynamic characteristics of magnesium vapor condensation is an important index to measure its continuity.Under the condition offlowing argon as the protective gas,when the condensation plate spacing is 10 cm,the surface roughness amplitude variance is 2,and the carrier gasflow rate is 20×10^(-3) m/s,the magnesium vapor has a better condensation effect,and the condensation efficiency formula is derived. 展开更多
关键词 relative vacuum Flow field disturbance Pidgeon MAGNESIUM CONDENSATION CONTINUITY
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Seasonal population trend and relative occurrence of pests and their natural enemies among cotton species and cultivars in India 被引量:1
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作者 NAGRARE V.S. NAIKWADI Bhausaheb +4 位作者 FAND Babasaheb B. NAIK V.Chinna Babu TENGURI Prabhulinga GOKTE‑NARKHEDKAR Nandini WAGHMARE V.N. 《Journal of Cotton Research》 2025年第2期178-192,共15页
Background Cotton crop is infested by numerous arthropod pests from sowing to harvesting,causing substantial direct and indirect yield losses.Knowledge of seasonal population trends and the relative occurrence of pest... Background Cotton crop is infested by numerous arthropod pests from sowing to harvesting,causing substantial direct and indirect yield losses.Knowledge of seasonal population trends and the relative occurrence of pests and their natural enemies is required to minimize the pest population and yield losses.In the current study,analysis of the seasonal population trend of pests and natural enemies and their relative occurrence on cultivars of three cotton species in Central India has been carried out.Results A higher number and diversity of sucking pests were observed during the vegetative cotton growth stage(60 days after sowing),declining as the crop matured.With the exception of cotton jassid(Amrasca biguttula biguttula Ishida),which caused significant crop damage mainly from August to September;populations of other sucking insects seldom reached economic threshold levels(ETL)throughout the studied period.The bollworm complex populations were minimal,except for the pink bollworm(Pectinophora gossypiella Saunders),which re-emerged as a menace to cotton crops during the cotton cropping season 2017–2018 due to resistance development against Bt-cotton.A reasonably good number of predatory arthropods,including coccinellids,lacewings,and spiders,were found actively preying on the arthropod pest complex of the cotton crop during the early vegetative growth stage.Linear regression indicates a significant relationship between green boll infestations and pink bollworm moths in pheromone traps.Multiple linear regression analyse showed mean weekly weather at one-or two-week lag periods had a significant impact on sucking pest population(cotton aphid,cotton jassid,cotton whitefly,and onion thrips)fluctuation.Gossypium hirsutum cultivars RCH 2 and DCH 32,and G.barbadense cultivar Suvin were found susceptible to cotton jassid and onion thrips.Phule Dhanvantary,an G.arboreum cotton cultivar,demonstrated the highest tolerance among all evaluated cultivars against all sucking pests.Conclusion These findings have important implications for pest management in cotton crops.Susceptible cultivars warrant more attention for plant protection measures,making them more input-intensive.The choice of appropriate cultivars can help minimize input costs,thereby increasing net returns for cotton farmers. 展开更多
关键词 COTTON PESTS Population trend relative occurrence CULTIVARS Natural enemies
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