Partitioning

分区
  • 文章类型: Journal Article
    全球数百万个湖泊冻结,然而,淡水系统中冰中的全氟烷基物质和多氟烷基物质(PFAS)的命运却知之甚少。我们量化了36个PFAS的浓度,溶解有机碳(DOC)和七个淡水湖的冰和水中的无机离子,以研究冻结期间离子的优先排除。冰中的PFAS浓度通常低于水柱中的PFAS浓度,证明这些化学物质在冰冻结时被排除在外。然而,相对于阳离子,PFAS和DOC均优先分配,平均钠归一化富集因子(EF)范围为全氟丁酸(PFBA;C4全氟羧酸)的2.74至全氟辛烷磺酸(PFOS;C8全氟磺酸)的4.01,DOC的类似EF值为4.14。水柱中PFAS的实验室实验和季节性测量表明,冰中PFAS的浓度是水性PFAS浓度的函数,在PFAS浓度较高的水中观察到较低的EF值。了解PFAS在淡水冰中的行为对于预测冬季和春季的污染物命运非常重要。影响冬季暴露于PFAS和淡水系统中冰融化时PFAS的释放。
    Millions of lakes worldwide freeze, yet the fate of per- and polyfluoroalkyl substances (PFAS) in ice in freshwater systems is poorly understood. We quantified concentrations of 36 PFAS, dissolved organic carbon (DOC), and inorganic ions in ice and water in seven freshwater lakes to investigate the preferential exclusion of ions during freezing. PFAS concentrations in ice are typically lower than in the water column, demonstrating that these chemicals are excluded from ice as it freezes. However, there is preferential partitioning of both PFAS and DOC relative to cations with average sodium-normalized enrichment factors (EF) ranging from 2.74 for perfluorobutanoate (PFBA; a C4 perfluorocarboxylic acid) to 4.01 for perfluorooctanesulfonate (PFOS; a C8 perfluorosulfonic acid), with a similar EF value of 4.14 for DOC. Laboratory experiments and seasonal measurements of PFAS in the water column indicate that PFAS concentrations in ice are a function of aqueous PFAS concentrations, with lower EF values observed in waters with higher PFAS concentrations. Understanding PFAS behavior in freshwater ice is important for predicting contaminant fate during winter and spring periods, with implications for exposure to PFAS during the winter and release of PFAS when ice melts in freshwater systems.
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  • 文章类型: Journal Article
    毒素-抗毒素(TA)模块广泛存在于病原菌的基因组中。它们调节重要的细胞功能,如转录,翻译,和DNA复制,因此对细菌在压力下的生存至关重要。专注于II型parDE模块,这项研究彻底检查了铜绿假单胞菌中的TAome,一种以其适应性和抗生素抗性而闻名的细菌。我们在三种铜绿假单胞菌菌株中探索了TAome:ATCC27,853,PAO1和PA14,并在ATCC27,853中发现了15种II型TA,在PAO1中发现了12种,在PA14中发现了13种,相关的可移动遗传元件存在显着差异。在ATCC27,853中通过进一步的TAome分析发现了五种不同的parDE同源物,并且通过序列比对和精确的基因组位置确认了它们的关系。在将这些ParDE模块序列与其他致病菌的序列进行比较后,发现它们被保存在许多分类单元中,尤其是变形杆菌.核酸被预测为ParD抗毒素的潜在配体,而ParE毒素与广泛的小分子相互作用,表明不同的功能曲目。通过蛋白质-蛋白质相互作用网络和对接研究阐明了ParDETA之间的相互作用界面,这也突出了参与结合的重要残基。这种彻底的检查提高了我们对多样性的理解,进化动力学,TA系统在铜绿假单胞菌中的功能意义,深入了解它们在细菌生理和致病性中的作用。
    Toxin-antitoxin (TA) modules are widely found in the genomes of pathogenic bacteria. They regulate vital cellular functions like transcription, translation, and DNA replication, and are therefore essential to the survival of bacteria under stress. With a focus on the type II parDE modules, this study thoroughly examines TAome in Pseudomonas aeruginosa, a bacterium well-known for its adaptability and antibiotic resistance. We explored the TAome in three P. aeruginosa strains: ATCC 27,853, PAO1, and PA14, and found 15 type II TAs in ATCC 27,853, 12 in PAO1, and 13 in PA14, with significant variation in the associated mobile genetic elements. Five different parDE homologs were found by further TAome analysis in ATCC 27,853, and their relationships were confirmed by sequence alignments and precise genomic positions. After comparing these ParDE modules\' sequences to those of other pathogenic bacteria, it was discovered that they were conserved throughout many taxa, especially Proteobacteria. Nucleic acids were predicted as potential ligands for ParD antitoxins, whereas ParE toxins interacted with a wide range of small molecules, indicating a diverse functional repertoire. The interaction interfaces between ParDE TAs were clarified by protein-protein interaction networks and docking studies, which also highlighted important residues involved in binding. This thorough examination improves our understanding of the diversity, evolutionary dynamics, and functional significance of TA systems in P. aeruginosa, providing insights into their roles in bacterial physiology and pathogenicity.
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  • 文章类型: Journal Article
    我们提出了开放量子系统中量子可观测物的分区,该分区继承于底层希尔伯特空间或配置空间的划分。表明,这种划分导致了通用的不均匀连续性方程的定义,非本地可观测值。这种形式主义用于描述独立量子粒子系统的冯·诺依曼熵的局部演化。至关重要的是,我们发现熵的所有局部波动都由熵电流算子控制,这意味着纠缠熵的产生不是由这个划分的熵来衡量的。对于从平衡线性扰动的系统,这表明,这个熵电流相当于一个热电流,前提是系统-储层耦合对称地划分。最后,我们证明了耦合的任何其他分区都直接导致冯·诺依曼熵的发散。因此,我们得出结论,希尔伯特空间分区是冯·诺依曼熵的唯一分区,符合热力学定律。
    We present a partition of quantum observables in an open quantum system that is inherited from the division of the underlying Hilbert space or configuration space. It is shown that this partition leads to the definition of an inhomogeneous continuity equation for generic, non-local observables. This formalism is employed to describe the local evolution of the von Neumann entropy of a system of independent quantum particles out of equilibrium. Crucially, we find that all local fluctuations in the entropy are governed by an entropy current operator, implying that the production of entanglement entropy is not measured by this partitioned entropy. For systems linearly perturbed from equilibrium, it is shown that this entropy current is equivalent to a heat current, provided that the system-reservoir coupling is partitioned symmetrically. Finally, we show that any other partition of the coupling leads directly to a divergence of the von Neumann entropy. Thus, we conclude that Hilbert-space partitioning is the only partition of the von Neumann entropy that is consistent with the laws of thermodynamics.
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  • 文章类型: Journal Article
    作为新兴的有机污染物,聚卤化咔唑(PHCZ)由于其在环境中的广泛分布和二恶英样毒性而引起了广泛关注。然而,对印染厂污染环境中PHCZs的分布和形成机制的研究还很缺乏。这里,在曹e河的样本中检测到11个PHCZ,中国,被印染严重污染的典型河流。土壤中的PHCZ浓度,沉积物,水样为8.3-134.5ng/g(中位数:26.3ng/g),17.7-348.8ng/g(中位数:64.2ng/g),和1.2-41.4μg/L(中位数:4.8μg/L),分别。3,6-二氯咔唑是主要的同源物,分析结果和形成机制都证明了这一点。水沉积物系统中的PHCZ迁移模式表明,高度卤化的PHCZ倾向于转移到沉积物中。此外,PHCZ是持久的,可以进行远距离运输,并通过模型对水生生物构成高风险。从染料生产中释放到环境中的PHCZ可以通过在染料合成过程中形成的咔唑或PHCZ的卤化而形成。卤化靛蓝染料的加热,和高卤化PHCZs的光解。这是首次揭示环境中印染植物活动对PHCZs影响的综合研究。
    As emerging organic contaminants, Polyhalogenated carbazoles (PHCZs) have caused wide concerns due to their wide distribution in the environment and dioxin-like toxicity. Nevertheless, research on the distribution and formation mechanisms of PHCZs in polluted environment of printing and dyeing plants is lacking. Here, 11 PHCZs were detected in samples from the Cao\'e River, China, a typical river heavily polluted by printing and dyeing. The PHCZs concentrations in the soil, sediment, and water samples were 8.3-134.5 ng/g (median: 26.3 ng/g), 17.7-348.8 ng/g (median: 64.2 ng/g), and 1.2-41.4 μg/L (median: 4.8 μg/L), respectively. 3,6-dichlorocarbazole was the dominant congener, proved by both analysis results and formation mechanisms. PHCZ migration patterns in water-sediment systems indicated that highly halogenated PHCZs tend to be transferred to sediment. Furthermore, PHCZs are persistent, can undergo long-range transport, and pose high risks to aquatic organisms by models. PHCZs released from dye production into environment can be form through halogenation of carbazole or PHCZs formed during the dye synthesis, heating of halogenated indigo dyes, and photolysis of highly halogenated PHCZs. This is the first comprehensive study to reveal the impact of printing and dyeing plant activities on PHCZs in the environment.
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  • 文章类型: Journal Article
    本文旨在强调自然生态系统中各种新兴污染物(EC)混合物的发生,并强调了由于不受管制地释放到土壤和水中而引起的主要关注。以及它们对人类健康的影响。新兴的污染物混合物,包括药品,个人护理产品,二恶英,多氯联苯,杀虫剂,抗生素,杀生物剂,表面活性剂,邻苯二甲酸酯,肠道病毒,和微塑料(MPs),被认为是具有严重影响的有毒污染物。MP在将污染物输送到水生和陆地生态系统中起着至关重要的作用,因为它们与土壤和水环境的各个组成部分相互作用。这篇综述总结了主要的新兴污染物(ECs),比如甲氧苄啶,双氯芬酸,磺胺甲恶唑,和17α-炔雌醇,对公众健康构成严重威胁,并导致抗菌素耐药性。在解决人类健康问题和补救技术方面,这篇综述严格评估了从复杂基质中去除ECs的常规方法。周围环境的不同物理化学性质促进了ECs向沉积物和其他有机相的分配。导致致癌,致畸,和雌激素效应通过芳香烃受体介导的活性催化作用和机制。ECs混合物络合的主动毒性,在某种程度上,尚未确定的EC的环境混合物代表了当前文献中的一个盲点,需要概念框架来评估单个组分和混合物的毒性和风险。最后,这篇综述最后对未来的范围进行了深入的探索,知识差距,和挑战,强调需要齐心协力管理ECs和其他有机污染物。
    This paper aims to emphasize the occurrence of various emerging contaminant (EC) mixtures in natural ecosystems and highlights the primary concern arising from the unregulated release into soil and water, along with their impacts on human health. Emerging contaminant mixtures, including pharmaceuticals, personal care products, dioxins, polychlorinated biphenyls, pesticides, antibiotics, biocides, surfactants, phthalates, enteric viruses, and microplastics (MPs), are considered toxic contaminants with grave implications. MPs play a crucial role in transporting pollutants to aquatic and terrestrial ecosystems as they interact with the various components of the soil and water environments. This review summarizes that major emerging contaminants (ECs), like trimethoprim, diclofenac, sulfamethoxazole, and 17α-Ethinylestradiol, pose serious threats to public health and contribute to antimicrobial resistance. In addressing human health concerns and remediation techniques, this review critically evaluates conventional methods for removing ECs from complex matrices. The diverse physiochemical properties of surrounding environments facilitate the partitioning of ECs into sediments and other organic phases, resulting in carcinogenic, teratogenic, and estrogenic effects through active catalytic interactions and mechanisms mediated by aryl hydrocarbon receptors. The proactive toxicity of ECs mixture complexation and, in part, the yet-to-be-identified environmental mixtures of ECs represent a blind spot in current literature, necessitating conceptual frameworks for assessing the toxicity and risks with individual components and mixtures. Lastly, this review concludes with an in-depth exploration of future scopes, knowledge gaps, and challenges, emphasizing the need for a concerted effort in managing ECs and other organic pollutants.
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  • 文章类型: Journal Article
    这篇综述涵盖了双水相体系(ATPS)中蛋白质分配的分析应用。我们回顾了过去二十年来在ATPS中蛋白质分配的分析应用方面的进展。不同应用的多个例子,例如重组蛋白的质量控制,蛋白质错误折叠的分析,表征结构变化小至单点突变,不同配体结合时的构象变化,蛋白质-蛋白质相互作用的检测,并介绍了蛋白质结构不同同工型的分析。发现已知靶标新药的新方法(例如,a受体)是在一种或多种先前药物已经具有充分表征的生物学功效谱时描述的。
    This review covers the analytical applications of protein partitioning in aqueous two-phase systems (ATPSs). We review the advancements in the analytical application of protein partitioning in ATPSs that have been achieved over the last two decades. Multiple examples of different applications, such as the quality control of recombinant proteins, analysis of protein misfolding, characterization of structural changes as small as a single-point mutation, conformational changes upon binding of different ligands, detection of protein-protein interactions, and analysis of structurally different isoforms of a protein are presented. The new approach to discovering new drugs for a known target (e.g., a receptor) is described when one or more previous drugs are already available with well-characterized biological efficacy profiles.
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  • 文章类型: Journal Article
    系统发育分析已进入基因组学(多位点)时代。对于经验不足的研究人员来说,征服基于多位点的系统发育重建所需的大量软件程序可能有些令人生畏且耗时。PhyloSuite,具有用户友好GUI的软件,旨在通过整合多位点和单基因系统发育所需的多个软件程序,并进一步简化整个过程,从而使这一过程更易于访问。在这个协议中,我们的目的是解释如何在PhyloSuite中进行系统发育管道和基于树的分析的每个步骤。我们还提出了一个新版本的PhyloSuite(v1.2.3),其中我们修复了一些错误,做了一些优化,并引入了一些新功能,包括一些基于树的分析,如信噪比计算,饱和度分析,虚假物种鉴定,等。分步协议包括背景信息(即,步骤做什么),原因(即,为什么要执行步骤),和操作(即,如何做到这一点)。该协议将帮助研究人员快速启动他们的方式通过多位点系统发育分析,尤其是那些有兴趣进行基于细胞器的分析。
    Phylogenetic analysis has entered the genomics (multilocus) era. For less experienced researchers, conquering the large number of software programs required for a multilocus-based phylogenetic reconstruction can be somewhat daunting and time-consuming. PhyloSuite, a software with a user-friendly GUI, was designed to make this process more accessible by integrating multiple software programs needed for multilocus and single-gene phylogenies and further streamlining the whole process. In this protocol, we aim to explain how to conduct each step of the phylogenetic pipeline and tree-based analyses in PhyloSuite. We also present a new version of PhyloSuite (v1.2.3), wherein we fixed some bugs, made some optimizations, and introduced some new functions, including a number of tree-based analyses, such as signal-to-noise calculation, saturation analysis, spurious species identification, and etc. The step-by-step protocol includes background information (i.e., what the step does), reasons (i.e., why do the step), and operations (i.e., how to do it). This protocol will help researchers quick-start their way through the multilocus phylogenetic analysis, especially those interested in conducting organelle-based analyses.
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  • 文章类型: Journal Article
    热垃圾渗滤液蒸发器系统可以减少高达97%的渗滤液体积,同时释放水蒸气并产生现场管理的残留物(体积减少的渗滤液和污泥)。现场热蒸发器为垃圾填埋场操作员提供了渗滤液管理自主权,而无需遵守日益严格的废水处理厂要求。然而,关于PFAS在这些系统中的划分知之甚少,也不包括PFAS通过蒸汽排放到环境中的程度。在这项研究中,饲料渗滤液,残留的蒸发渗滤液,污泥,和冷凝的蒸气在两个有源的全尺寸热垃圾渗滤液蒸发器和实验室规模的渗滤液蒸发实验中采样。通过超高压液相色谱-串联质谱法(UHPLC-MS/MS)分析样品的91PFAS。从蒸发器1,蒸发器2和实验室规模的蒸发器观察到类似的趋势;在蒸发过程中,∑PFAS在残留的蒸发浸出液中浓缩了5.3至20倍。采样的所有冷凝蒸气(n=5)均含有PFAS,主要是5:3氟调聚物羧酸(5:3FTCA),(全尺寸蒸气729-4087ng/LPFAS;实验室规模蒸气61.0ng/LPFAS)。对于蒸发器1和2,估计为9-24%和10%,分别,在样品收集期间,渗滤液中进入蒸发器的PFAS质量随蒸汽一起释放。\'.
    Thermal landfill leachate evaporator systems can reduce the volume of leachate by up to 97%, while releasing water vapor and producing residuals (volume-reduced leachate and sludge) that are managed on-site. On-site thermal evaporators offer landfill operators leachate management autonomy without being subject to increasingly stringent wastewater treatment plant requirements. However, little is known about the partitioning of PFAS within these systems, nor the extent to which PFAS may be emitted into the environment via vapor. In this study, feed leachate, residual evaporated leachate, sludge, and condensed vapor were sampled at two active full-scale thermal landfill leachate evaporators and from a laboratory-scale leachate evaporation experiment. Samples were analyzed for 91 PFAS via ultra-high pressure liquid chromatography - tandem mass spectrometry (UHPLC-MS/MS). Similar trends were observed from Evaporator 1, Evaporator 2, and the laboratory-scale evaporator; ∑PFAS were concentrated in the residual evaporated leachate during evaporation by a factor of 5.3 to 20. All condensed vapors sampled (n = 5) contained PFAS, predominantly 5:3 fluorotelomer carboxylic acid (5:3FTCA), (full-scale vapors 729 - 4087 ng/L PFAS; lab-scale vapor 61.0 ng/L PFAS). For Evaporators 1 and 2, an estimated 9 - 24% and 10%, respectively, of the PFAS mass entering the evaporators in leachate was released with vapor during the days of sample collection. \'.
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  • 文章类型: Journal Article
    了解物候学,它的遗传学和农艺后果,对作物适应至关重要。在这里,我们的目标是(1)表征扁豆对光周期的反应,重点是五个基因座:扁豆ELF3直系同源Sn,与扁豆FT直向同源物簇相关的两个基因座和2号和5号染色体中没有候选物的两个基因座(实验。1:36行,phytotron中的短期和长期日);(2)建立物候与产量的关系(实验。2:25行,11场环境)。复古的视角,我们量化了30年育种过程中表型的时间趋势,把两个实验联系起来。在29kgha-1yr-1或1.5%yr-1时,从较老品种到较新品种的产量线性增加,在冬季和夏季降雨条件下,与开花时间呈负相关,在有利的环境中与生物质脱钩。开花时间从较老的品种缩短到较新的品种,在该领域-0.56%yr-1,以及-0.42%yr-1(短日)和-0.99%yr-1(长日)。不同起源的早花系携带五个基因座的多个早期等位基因,表明这些基因座中至少有一些对物候有附加影响。当前的种质主要具有FTb簇区域的早期开花单倍型,因此有可能增加具有产量影响的物候多样性。
    Understanding phenology, its genetics and agronomic consequences, is critical for crop adaptation. Here we aim at (1) characterising lentil response to photoperiod with a focus on five loci: the lentil ELF3 ortholog Sn, two loci linked to clusters of lentil FT orthologs and two loci without candidates in chromosomes 2 and 5 (exp. 1: 36 lines, short and long day in phytotron); (2) establishing phenology-yield relationship (exp. 2: 25 lines, 11 field environments). A vintage perspective, where we quantify time trends in phenotype over three decades of breeding, links both experiments. Yield increased linearly from older to newer varieties at 29 kg ha-1 yr-1 or 1.5% yr-1, correlated negatively with flowering time in both winter- and summer-rainfall regimes, and decoupled from biomass in favourable environments. Time to flowering shortened from older to newer varieties at -0.56 % yr-1 in the field, and -0.42 % yr-1 (short day) and -0.99 % yr-1 (long day) in the phytotron. Early-flowering lines of diverse origin carried multiple early alleles for the five loci, indicating that at least some of these loci affect phenology additively. Current germplasm primarily features the early flowering haplotype for an FTb cluster region, hence the potential to increase phenological diversity with yield implications.
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  • 文章类型: Journal Article
    由于厄尔尼诺现象和全球气候变化,巴西半干旱地区的干旱变得更加严重和频繁。Jaguaribe河口是一个半干旱的生态系统,由于干旱和堤坝,淡水排放量减少。淡水通量的减少通过增加Jaguaribe河口的水停留时间来增加金属的利用率。然后,这项研究旨在评估严重干旱后Jaguaribe河口的溶解有机物质量及其与金属的相互作用。它是通过碳分析进行的,荧光光谱法,超滤技术,并通过ICP-MS测定金属。光学分析表明,溶解的有机碳(DOC)主要由陆源腐殖质化合物组成,而颗粒有机碳(POC)和叶绿素a之间的低比率表明POC主要是浮游植物来源的。在河口混合过程中,DOC和POC表现出非保守性去除。DOM和溶解元素主要分布在LMW部分中,在胶体部分中的百分比较低。Li,Rb,Sr,Mo,U表现出保守的行为,而Cu,Fe,Cr,V具有非保守行为,与DOM呈显著正相关,即使在雨季,DOM也是Jaguaribe河口金属可用性的相关驱动因素。
    Droughts are becoming more intense and frequent in the Brazilian semiarid because of El Niño and global climate changes. The Jaguaribe River estuary is a semiarid ecosystem that experiences a reduction in freshwater discharges due to droughts and river damming. The decrease in freshwater fluxes has increased metal availability through the water residence time increase in the Jaguaribe River estuary. Then, this study aimed to evaluate the dissolved organic matter quality and its interaction with metals in the Jaguaribe River estuary after a severe drought period. It was performed through carbon analyses, fluorescence spectroscopy, ultrafiltration technique, and determinations of metals by ICP-MS. Optical analysis showed that the dissolved organic carbon (DOC) was preponderantly composed of terrestrial-derived humic compounds, while the low ratio between the particulate organic carbon (POC) and chlorophyll-a indicated that POC was predominantly phytoplankton-derived. DOC and POC presented non-conservative removal during the estuarine mixing. DOM and dissolved elements were mostly distributed within the LMW fraction and presented a low percentage in the colloidal fraction. Li, Rb, Sr, Mo, and U showed conservative behavior, while Cu, Fe, Cr, and V had non-conservative behavior with a significant positive correlation with DOM, suggesting DOM as a relevant driver of metal availability at the Jaguaribe River estuary even during the rainy season.
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