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Navigating the Challenges of Emerging Contaminants to Protect Human and Ecological Health

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Engineering 2024年第6期37卷 1-2页

作者： Jiuhui Qu michael r.Hoffmann Gang Yu School of Environment Tsinghua UniversityBeijing 100084China Linde-robinson Laboratories California Institute of TechnologyPasadenaCA 91125USA Advanced Interdisciplinary Institute of Environmental and Ecology Beijing Normal UniversityZhuhai 519000China

Emerging contaminants are defined as chemicals that are not currently(or have only recently been)regulated and about which there are concerns regarding their impact on human or ecological *** contaminants are widely detected in air,water,soil,sediment,and biotic *** is against this backdrop of urgency that we have curated this special issue titled“Emerging Contaminants Control:Science and Technology,”with the goal of uniting the latest scientific insights and pioneering strategies to address this global *** special issue embarks on a comprehensive examination of the emerging contaminants dilemma,covering aspects such as risk assessment,remediation technologies,environmental surveying,and the broader implications for *** a collection of articles,we probe deep into the core of this issue,showcasing studies that range from appraising environmental risks to forging new methods for treatment and scrutinizing the occurrence of contaminants across different environmental settings.

关键词： Ecological surveying environmental

Basis for the diversity and extent in loss of digestible nutrients created by dietary phytin: Emphasis on fowl and swine

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Animal Nutrition 2024年第1期16卷 422-428页

作者： Edwin T.Moran michael r.Bedford Poultry Science Department Auburn University AB Vista Woodstock Court Blenheim Road

Phytin is the Ca2+-Mg2+-K+salt of phytic acid that is created and deposited in the aleurone layer and/or germ of grains and legumes. Its high presence in feedstuffs for fowl and swine diets results in it being a universal and significant impediment to optimum performance. Phytin impairs gastrointestinal recovery of a wide array of nutrients, the effect varying with the nutrient concerned. On exposure to low pH during gastric digestion, phytin dissociates into phytic acid and solubilized Ca2+. Even at low gastric pH,phytic acid is negatively charged which forms the basis of its anti-nutritive behavior. Pepsinogen has extensive basic amino acids on its activation peptide that are presented as cations at low pH which are targeted by pepsin for activation. Partially crystalized Ca2+near the enzyme?s active site further stabilizes its newly formed structure. Thus, phytic acid appears to interfere with gastric digestion by several mechanisms; interfering with pepsinogen activation by binding to the polypeptide?s basic amino acids;coordinating free Ca2+, destabilizing pepsin; binding some dietary proteins directly, further compromising gastric proteolysis. Upon digesta attaining neutrality in the duodenum, Ca2+and other cations rebind with accessible anions, phytic acid being a significant contender. Phytate not only binds free cations but can also strip them from enzymes(e.g. Ca2+, Zn2+) which reduces their structural resistance to autolysis and ability as co-factors(e.g. Zn2+) to increase enzyme activity. Goblet cells initially employ Ca2+as an electronic shield between mucin layers enabling granule formation and cell storage. After mucin granule release, Ca2+is progressively displaced by Na+to free the viscous mucins enabling its translocation. Mucin entangles with the glycocalyx of adjacent enterocytes thereby constructing the unstirred water layer（USWL）. Excessive removal of Ca2+from mucin by phytic acid increases its fluidity facilitating its loss from the USWL with

关键词： Digestive enzyme Calcium Endogenous protein Mucin Phytin

Dietary fibre effects and the interplay with exogenous carbohydrases in poultry nutrition

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Animal Nutrition 2024年第1期16卷 231-240页

作者： michael r.Bedford Birger Svihus Aaron J.Cowieson AB Vista Feed Ingredients Ltd Norwegian University of Life Sciences DSM Nutritional Products

A comprehensive understanding of the role of dietary fibre in non-ruminant animal production is elusive. Equivocal and conflated definitions of fibre coupled with significant analytical complexity,interact with poorly defined host and microbiome relationships. Dietary fibre is known to influence gut development, feed intake and passage rate, nutrient absorption, microbiome taxonomy and function, gut p H, endogenous nutrient loss, environmental sustainability, animal welfare and more. Whilst significant gaps persist in our understanding of fibre in non-ruminant animal production, there is substantial interest in optimizing the fibre fraction of feed to induce high value phenotypes such as improved welfare,live performance and to reduce the environmental footprint of animal production systems. In order to achieve these aspirational goals, it is important to tackle dietary fibre with the same level of scrutiny as is currently done for other critical nutrient classes such as protein, minerals and vitamins. The chemical,mechanical and nutritional role of fibre must be explored at the level of monomeric sugars, oligosaccharides and polysaccharides of varying molecular weight and decoration, and this must be in parallel to standardisation of analytical tools and definitions for speciation. To further complicate subject, exogenous carbohydrases recognise dietary fibre as a focal substrate and have varying capacity to generate lower molecular weight carbohydrates that interact differentially with the host and the enteric microbiome. This short review article will explore the interactive space between dietary fibre and exogenous carbohydrases and will include their nutritional and health effects with emphasis on functional development of the gut, microbiome modulation and host metabolism.

关键词： Fibre Carbohydrase Nutrition Microbiome Gastro-intestinal development Feed

评估饮用水中化学物暴露与健康结局：认识和研究需求现状

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环境与职业医学 2014年第8期31卷 651-657页

作者： Cristina M.Villanueva Manolis Kogevinas Sylvaine Cordier michael r.templeton roel Vermeulen John r.Nuckols Mark J.Nieuwenhuijsen Patrick Levallois 汪源张伊人何蓉金泰廙 Centre for research in Environmental Epidemiology(CrEAL) IMIM(Hospital del Mar Medical research Institute) CIBEr Epidemiología y Salud Pública(CIBErESP) National Institute of Public Health Inserm(Institut National de la Santé et de la recherche Médicale)UMr 1085 IRSET(Institut de Recherche Santé Environnement et Travail)Université de Rennes 1 Imperial College London Department of Civil and Environmental Engineering Environmental Epidemiology Division Institute for Risk Assessment Sciences(IRAS)Utrecht University Department of Environmental and radiological Health Sciences Colorado State University Université Laval Québec Institut National de Santé Publique du Québec Centre de recherche du Centre hospitalier universitaire(CHU)de Québec

[背景]安全的饮用水对于健康至关重要。虽然在全球范围内,微生物污染仍然是饮用水相关疾病发病率和死亡率的最主要原因,但在供水中的化学物也可能导致疾病,而其中一些的人体健康结局的证据有限或缺乏。[目的]旨在总结当前人们对这一问... 详细信息

[背景]安全的饮用水对于健康至关重要。虽然在全球范围内,微生物污染仍然是饮用水相关疾病发病率和死亡率的最主要原因,但在供水中的化学物也可能导致疾病,而其中一些的人体健康结局的证据有限或缺乏。[目的]旨在总结当前人们对这一问题的了解状况,找出认识差距,并为与饮用水中化学物相关的流行病学研究提供建议。[讨论]评估饮用水中化学物暴露与健康结局十分具有挑战性。暴露通常为低浓度,在水中测量是通常是不够的,化学物以混合物形式存在,暴露时间通常很长,可能涉及多个暴露途径,而能够反映相应暴露阶段的有效生物标志却很少。此外,相对风险的幅度具有变小趋势。[结论]研究应该包括:设计良好的流行病学研究,涵盖能够比较污染程度并具有足够样本量的地区;结合生物分析并整合复杂混合物影响的污染物产生综合评价;足够水中测量次数,以评估地理和时间变异性;有关导致暴露的个人生活习惯的详细信息(例如,摄入、淋浴、游泳和饮食);生物样本的采集,以测量相关的生物标志;先进的统计模型,以评估暴露和相对风险,并应考虑解决测量误差的方法。最后,纳入早期生物效应和遗传易感性的分子标志对于了解化学物作用机制是必不可少的。需要评估大量新出现的污染物的风险和人类暴露,但这些知识仍然缺乏。

关键词：健康结局饮用水化学物评估需求现状疾病发病率测量误差相对风险

规模化粪池污泥热解及与农业废弃物共热解的资源回收和生物炭特性分析

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环境卫生工程 2020年第5期28卷 96-96页

作者： Benedict C.Krueger Geoffrey D.Fowler michael r.templeton Berta Moya 赵玉莹(译) 程世昆(译) 李子富(审查) 英国帝国理工学院土木与环境工程系英国伦敦SW72AZ 美国康涅狄格州Biomass Controls LLC公司美国伍德斯托克北京科技大学环境科学与工程系

1研究亮点*首次对规模化粪池污泥制备生物炭进行了全面研究;*生物炭具备作为固体燃料和土壤改良剂的应用潜力;*化粪池污泥制备生物炭可以完全杀死病原体并且使重金属部分稳定化;*化粪池污泥和农业废弃物共处理提高了生物炭的理化特性。

关键词：化粪池污泥生物炭共热解环境卫生

review of Moirésuperconductivity and application of the roeser-Huber formula

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Superconductivity 2024年第1期9卷 9-28页

作者： michael r.Koblischka Anjela Koblischka-Veneva Institute of Experimental Physics Saarland UniversityCampus C 6366123 SaarbrückenGermany

Moirésuperconductivity represents a new class of superconducting materials since the discovery of superconductivity in magic‐angle(1.1°)twisted bi‐layer graphene(MATBG),forming a Moirélattice with a much bigger crystal parameter as the original lattice constant of ***,experimentally changing the Moirétwist angle,0.93°≤Θ≤1.27,leads to a variation of the superconducting properties and enables a new way of engineering 2D superconducting *** of the robust superconducting state of MATBG as function of charge carrier density,temperature and applied magnetic fields are *** influence of the top/bottom hexagonal boron nitride layer thickness on the superconducting properties of MATBG was also demonstrated in the *** all fabricated MATBG devices,changing of the charge carrier density leads to the appearance of insulating,metallic and even ferromagnetic states,which separate several superconducting domes in the phase diagram(longitudinal resistance,rxx,as function of temperature T and charge carrier density,n).Further works have considered MATBG combined with WSe2‐layers,twisted bi‐layer WSe2,magic‐angle trilayer graphene(MATTG),and most recently,four‐layer(MAT4G)and five‐layer(MAT5G)*** differences between the layered,cuprate high‐Tc superconductors and the Moirésuperconductors are compiled *** collected information is then used to apply the roeser‐Huber formalism to Moiré‐type superconductivity to calculate the superconducting transition temperature,Tc,using only information of the Moirélattice and the electronic *** account for the different charge carrier densities in the experimental data sets and the low charge carrier mass demands that a new parameterηmust be introduced to the roeser‐Huber formalism to enable the description of several superconducting domes found in the phase diagram for a given Moiré*** so,the calculated data fit well to the correlation curve defined within the roeser‐Hube

关键词： MoiréSuperconductors Twisted bilayer graphene Magic angle Multilayer graphene stacks Superconducting transition temperature roeser‐Huber formalism

Dietary xylo‑oligosaccharides and arabinoxylans improved growth efficiency by reducing gut epithelial cell turnover in broiler chickens

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Journal of Animal Science and Biotechnology 2024年第3期15卷 1325-1335页

作者： Carla Castro Shahram Niknafs Gemma Gonzalez‑Ortiz Xinle Tan michael r.Bedford Eugeni roura Centre for Nutrition and Food Sciences Queensland Alliance for Agriculture and Food InnovationThe University of QueenslandSt LuciaQLD 4072Australia AB Vista MarlboroughWiltshire SN84ANUK

Background One of the main roles of the intestinal mucosa is to protect against environmental ***-mentation of xylo-oligosaccharides(XOS)is known to selectively stimulate the growth of beneficial intestinal bacteria and improve gut health and function in *** may have an impact on the integrity of the intestinal epithelia where cell turnover is critical to maintain the compatibility between the digestive and barrier *** aim of the study was to evaluate the effect of XOS and an arabinoxylan-rich fraction(AXrF)supplementation on gut func-tion and epithelial integrity in broiler *** A total of 128 broiler chickens(ross 308)were assigned into one of two different dietary treatments for a period of 42 d:1)control diet consisting of a corn/soybean meal-based diet;or 2)a control diet supplemented with 0.5%XOS and 1%*** treatment was randomly distributed across 8 pens(n=8)with 8 chickens *** intake and body weight were recorded *** d 42,one male chicken per pen was selected based on aver-age weight and euthanized,jejunum samples were collected for proteomics *** Dietary XOS/AXrF supplementation improved feed efficiency(Prom d 1 to 42 compared to the con-trol *** analysis was used to understand the mechanism of improved efficiency uncovering 346 dif-ferentially abundant proteins(DAP)(Padjred to the non-supplemented *** the jejunum,the DAP translated into decreased ATP production indicating lower energy expenditure by the tissue(e.g.,inhibition of glycolysis and tricarboxylic acid cycle pathways).In addition,DAP were associated with decreased epithelial cell differentiation,and migration by reducing the actin polymerization ***-ting the two main pathways together,XOS/AXrF supplementation may decrease around 19%the energy required for the maintenance of the gastrointestinal *** Dietary XOS/AXrF supplementation improved gr

关键词： Actin Arabinoxylans Broiler Cell turnover Energy metabolism Jejunum Xylo-oligosaccharides

应对新污染物挑战，保护人类和生态健康（英文）

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Engineering 2024年第6期 1-2页

作者：曲久辉 michael r.Hoffmann 余刚 School of Environment Tsinghua University Linde-robinson Laboratories California Institute of Technology Advanced Interdisciplinary Institute of Environmental and Ecology Beijing Normal University

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Fabrication of sub-20 nm MoS_(2) horizontal nanowire on silicon substrates by inclusion of precursors into polystyrene-bpolyethylene oxide nanopatterns: Detailed structural investigation

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Nano research 2024年第3期17卷 2145-2153页

作者： Tandra Ghoshal michael A.Morris School of Chemistry AMBER and CRANNTrinity College DublinDublinIrelandD02 AK60

Herein,we demonstrate the fabrication of sub-20 nm MoS_(2) horizontal nanowire arrays on silicon substrates using a self-assembled block copolymer assisted in situ inclusion *** separated long-range ordered polystyrene-b-polyethylene oxide(PS-b-PEO)block copolymer(BCP)line-space nanopatterns were achieved through thermo-solvent *** patterns produced had long-range order and domain sizes>1μ*** BCP structures were lightly etched and modified by anhydrous ethanol to facilitate insertion of molybdenum precursor within the film maintaining the parent BCP *** ordered molybdenum oxide nanowire arrays were then fabricated by ultraviolet(UV)/ozone treatment at room *** oxides were converted to sulphides by thermal evaporation at different temperatures in Ar/H_(2) environment.X-ray photoelectron spectroscopy revealed the composition and phases of the molybdenum oxide and sulphide *** mapping was performed to investigate the interfaces between the oxide and sulphide nanowires with the substrate *** formation and stability of the sulphide nanowires were studied at different *** photoluminescence and raman properties were studied at different formation temperatures to investigate defects and estimate the number of layers.

关键词： MoS_(2) block copolymer nanowires inclusion X-ray photoelectron spectroscopy(XPS) mapping photoluminescence