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Temporal variability and sources of PFAS in the Rio Grande,New Mexico through an arid urban area using multiple tracers and highfrequency sampling

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Emerging Contaminants 2024年第3期10卷 205-220页

作者： Kimberly R.Beisner Rebecca E.Travis david A.Alvarez Larry B.Barber jacob A.Fleck jeramy R.jasmann U.S.Geological Survey 6700 Edith Blvd NEAlbuquerqueNM87113USA U.S.Geological Survey 4200 New Haven RoadColumbiaMO65201USA U.S.Geological Survey 3215 Marine St.BoulderCO80303USA U.S.Geological Survey 6000 J St.Placer Hall.SacramentoCA95819USA

Per-and polyfluoroalkyl substances(PFAS)are ubiquitous in the environment but sources are not well defined for temporal and spatial aspects within an urban environment,and especially for an arid urban environment subject to seasonal short term high-intensity precipitation events.A focused diel sampling was conducted in the summer of 2021 to assess the temporal and spatial variability of PFAS in the Rio Grande near Albuquerque,New Mexico and showed an order of magnitude increase of PFAS as it flows through the Albuquerque urban *** samples were collected at two different locations on the Rio Grande in addition to wastewater treatment plant(WWTP)effluent that discharges directly to the Rio Grande between the sampling ***-term high-intensity precipitation events occurred during the study period and mobilized PFAS from urban *** organic matter composed of tryptophan-like organic substances and refined fuel and fuel byproducts,characteristic of an urban signature,were also related to the precipitation *** PFAS in discharge from the WWTP was consistent over a 24-h period with slight differences in some *** presence on the Rio Grande downstream of the WWTP was evidenced by a gadolinium anomaly as well as increases in several other trace elements,total dissolved nitrogen,and fluorescence indicators,in addition to *** varied depending on source contribution,where urban runoff was associated with PFOA,PFOS,and PFBA,whereas PFHxA and PFPeA were associated with wastewater *** addition,passive polar organic chemical integrative samplers(POCIS)using hydrophilic-lipid balance(HLB)sorption media were deployed for a month at two locations on the Rio Grande to assess longer term PFAS *** POCIS results show some compounds(PFPeA and PFHpA)were greater than the average concentration from discrete samples,whereas other compounds(PFHxA,PFOA,PFDA,and PFNA)were lower in the POCIS,and PFOS was very simila

关键词： wastewater Rio runoff

Pre-operative visceral adipose tissue radiodensity is a potentially novel prognostic biomarker for early endoscopic post-operative recurrence in Crohn’s disease

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World journal of Gastrointestinal Surgery 2024年第3期16卷 740-750页

作者： Phillip Gu Shishir Dube Norman Gellada So Yung Choi Susan Win Yoo jin Lee Shaohong Yang Talin Haritunians Gil Y Melmed Eric A Vasiliauskas Niru Bonthala Gaurav Syal Andres j Yarur david Ziring Shervin Rabizadeh Phillip Fleshner Cindy Kallman Suzanne Devkota Stephan R Targan Dalin Li Dermot PB McGovern Department of Medicine Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Imaging Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Biostatistics Shared Resource Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Internal Medicine Keimyung University School of MedicineDaegu 42601South Korea Department of Medicine University of California at Los AngelesLos AngelesCA 90095United States Department of Medicine University of California at San DiegoSan DiegoCA 92093United States Department of Pediatrics Cedars-Sinai Medical CenterLos AngelesCA 90048United States Department of Surgery Cedars-Sinai Medical CenterLos AngelesCA 90048United States

BACKGROUND Evidence suggests inflammatory mesenteric fat is involved in post-operative recurrence(POR)of Crohn’s disease(CD).However,its prognostic value is INTRODUCTION Crohn’s disease(CD)is a debilitating chronic immune-mediated inflammatory disease(IMID)of the gastrointestinal tract that is increasing in incidence and prevalence globally[1].CD patients often undergo surgery for disease-related complic-ations and/or medically refractory ***,surgery is not curative,and many patients develop post-operative recurrence(POR)of CD with a significant proportion eventually requiring additional *** advances in early detection and therapeutics,the contemporary 10-year risk of surgery has improved from 50%to 26%,but the risk of recurrent surgery has remained unchanged at 30%,suggesting a need to improve post-operative management strategies[2].Presently,there are two accepted strategies to mitigate POR,but each have potential ***,patients start early post-operative pharmacologic prophylaxis within 4-6 wk after *** strategy can potentially overtreat a subset of patient who may not develop long-term disease recurrence off ***,these patients are at risk of medication-related adverse events and the direct and indirect costs associated with therapy with little or no benefit[3].The second strategy is performing early colonoscopy within 6-12 months after surgery and escalating therapy based on FOOTNOTES Author contributions:Gu P is the guarantor of the article and was involved in concept and design,data collection,statistical analysis,drafting of manuscript,and final approval of manuscript;Dube S and Choi SY were involved in statistical analysis,drafting of the manuscript,and final approval of manuscript;Gellada N,Win S,Lee Yj and Yang S were involved in the data collection,drafting of the manuscript,and final approval of manuscript;Haritunians T and Li D were involved in data analysis and interpretation,drafting

关键词： Crohn’s disease Surgery Visceral adipose tissue Mesenteric adipose tissue Creeping fat Computed tomography

High-speed silicon photonic electro-optic Kerr modulation

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Photonics Research 2024年第1期12卷 51-60页

作者： jONATHAN PELTIER WEIWEI ZHANG LEOPOLD VIROT CHRISTIAN LAFFORGUE LUCAS DENIEL DELPHINE MARRIS-MORINI GUY AUBIN FARAH AMAR DENH TRAN XINGZHAO YAN CALLUM G.LITTLEjOHNS CARLOS ALONSO-RAMOS KE LI david j.THOMSON GRAHAM REED LAURENT VIVIEN University Paris-Saclay CNRSCentre for Nanoscience and Nanotechnology(C2N)Palaiseau 91120France University Grenoble Alpes CEALETIGrenoble 38000France Optoelectronics Research Centre Zepler Institute for Photonics and NanoelectronicsFaculty of Engineering and Physical SciencesUniversity of SouthamptonSouthampton SO171BJUK

Silicon-based electro-optic modulators contribute to easing the integration of high-speed and low-power consumption circuits for classical optical communications and data *** the plasma dispersion modulation,an alternative solution in silicon is to exploit the DC Kerr effect,which generates an equivalent linear electro-optical effect enabled by applying a large DC electric *** some theoretical and experimental studies have shown its existence in silicon,limited contributions relative to plasma dispersion have been achieved in high-speed modulation so *** paper presents high-speed optical modulation based on the DC Kerr effect in silicon PIN *** contributions of both plasma dispersion and Kerr effects have been analyzed in different waveguide configurations,and we demonstrated that the Kerr induced modulation is dominant when a high external DC electric field is applied in PIN ***-speed optical modulation response is analyzed,and eye diagrams up to 80 Gbit/s in NRZ format are obtained under a *** of 30 *** work paves the way to exploit the Kerr effect to generate high-speed Pockels-like optical modulation.

关键词： waveguide dispersion effect

Natural products and drug discovery

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National Science Review 2022年第11期9卷 37-57页

作者： david j.Newman NIH Special Volunteer

This review covers the recent history of a series of very important natural products and their derivatives that are currently in use or under evaluation in the areas of anti-infectives, important cancer treatments that include antibody drug conjugates, followed by a discussion of type 2 diabetes(T2DM) drugs and angiotensin converting enzyme inhibitors. The current structures of the agents are shown, though in the case of some peptides used in T2DM drugs the standard single leTher abbreviation for an amino acid is used.

关键词： artemisinin glycopeptides anthracyclines dolastatin diabetes 2 ACE inhibitors

Positron emission particle tracking——Application and labelling techniques

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Particuology 2008年第1期6卷 16-23页

作者： david j. Parker School of Physics and Astronomy the University of Birmingham Edgbaston Birmingham B15 2TT UK

The positron emission particle tracking （PEPT） technique has been widely used in science and engineering to obtain detailed information on the motion and flow fields of fluids or granular materials in multiphase systems, for example, fluids in rock cracks, chemical reactors and food processors; dynamic behaviour of granular materials in chemical reactors, granulators, mixers, dryers, rotating kilns and ball mills. The information obtained by the PEPT technique can be used to optimise the design, operational conditions for a wide range of industrial process systems, and to evaluate modelling work. The technique is based on tracking radioactively labelled particles （up to three particles） by detecting the pairs of backto-back 511 keV γ-rays arising from annihilation of emitted positrons. It therefore involves a positron camera, location algorithms for calculating the tracer location and speed, and tracer labelling techniques. This paper will review the particle tracking technique from tracking algorithm, tracer labelling to their application.

关键词： PEPT Tracer Algorithm Tracking

Vlendelian randomization： loosening the Gordian knot of testosterone and male ageing

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Asian journal of Andrology 2013年第5期15卷 579-581页

作者： david j Handelsman ANZAC Research Institute University of SydneySydney NSW 2139 Australia

It is unknown whether the reduced blood testosterone among unselected older men （＂andropause＂） compared to healthy younger men is due to ageing per se or as a non-specific adaptive reaction to chronic diseases acc... 详细信息

关键词： Mendelian randomization loosening male ageing

Forest visualization at multiple scales for management and planning

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Science China(Technological Sciences) 2006年第Z1期49卷 27-34页

作者： david j.Mladenoff Department of Forest Ecology and Management

In this study forests were visualized at various scales by placing individual trees into a forest with realistic sizes and densities. Tree images were used from two sources: high quality field photos and images created using graphic design software. The terrain, species composition, and tree sizes and density from forest inventory were all represented in GIS data format. In addition, non-tree objects and features that are essential for close-to-reality visualization were combined with the tree images in a 3-D visualization software package. We further portrayed stand level effects by animating a simulated fly-through of a forest. To visualize temporal change, a case study of four different forest patches was animated. The advantages of this approach comparing to other visualization approaches are: (1) it represents the forests with realistic individual tree images; and (2) it maintains both visual and informational realism in a forest viewable from within-stand to landscape scales. Thus, this approach is realistic in two aspects. First, it is almost as realistic as a photograph, and secondly, its information content is actual forest composition, density, and height.

关键词： 3-D, visualization, forest, landscape, multiple scales.

A Model System of Development Regulated by the Long-distance Transport of mRNA

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journal of Integrative Plant Biology 2010年第1期52卷 40-52页

作者： david j. Hannapel Plant Biology Major 253 Horticulture Hall Iowa State University

BELl-like transcription factors are ubiquitous in plants and interact with KNOTTEDI-types to regulate numerous developmental processes. In potato, the RNA of several BELl-like transcription factors has been identified in phloem cells. One of these, StBEL5, and its Knox protein partner regulate tuber formation by targeting genes that control growth. RNA detection methods and grafting experiments demonstrated that StBEL5 transcripts move across a graft union to localize in stolon tips, the site of tuber induction. This movement of RNA originates in source leaf veins and petioles and is induced by a short-day photoperiod, regulated by the untranslated regions, and correlated with enhanced tuber production. Addition of the StBEL5 untranslated regions to another *** mRNA resulted in its preferential transport to stolon tips leading to increased tuber production. Upon fusion of the untranslated regions of StBEL5 to a β-glucuronidase marker, translation in tobacco protoplasts was repressed by those constructs containing the 3＇ untranslated sequence. The untranslated regions of the StBEL5 mRNA are involved in mediating its long-distance transport and in controlling translation. The 3＇ untranslated sequence contains an abundance of conserved motifs that may serve as binding motifs for RNA-binding proteins. Because of their presence in the phloem sieve tube system, their unique untranslated region sequences and their diverse RNA accumulation patterns, the family of BEL1-like RNAs from potato represents a valuable model for studying the long-distance transport of full-length mRNAs and their role in development.

关键词： BEL A Model System of Development Regulated by the Long-distance Transport of mRNA Long

Taxonomic and phylogenetic composition show biotic resistance to exotic invasion in acid seep springs

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Ecological Processes 2021年第1期10卷 77-88页

作者： david F.Barfknecht david j.Gibson School of Biological Sciences Southern Illinois University–CarbondaleCarbondaleIL 62901-6509USA

Background:Few studies have incorporated the evolutionary insights provided by analysis of phylogenetic structure along with community composition to assess the effects of exotic invasion on freshwater ***,we assess the taxonomic and phylogenetic relationships among acid seep springs to investigate the potential homogenization or resistance of communities due to invasion of an exotic ***:Multivariate community analyses indicated differences in community and phylogenetic composition and dispersion among acid seep springs,associated with gradients in soil moisture,canopy cover,and phylogenetic *** contrast,univariate analyses showed differences in taxonomic diversity but not phylogenetic diversity among acid seep ***:Despite exotic invasion,individual acid seep springs remained taxonomically and phylogenetically distinct from each *** and phylogenetic diversity metrics revealed different aspects of composition,reinforcing the importance of including both in analyses of plant communities for understanding community assembly following exotic invasion and for management *** acid seep springs,taxonomic and phylogenetic composition appear to be driven more through environmental filtering by light and moisture than by the competitive effects following invasion of an exotic grass in support of Elton’s biotic resistance hypothesis.

关键词： Acid seep springs Diversity Community Phylogenetics Exotic invasion Environmental filtering NMDS UniFrac Vector analysis