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Chinese Annals of Mathematics,Series B 2024年第1期45卷 81-122页

作者： Luca GALIMBERTI kenneth h.KARLSEN Department of Mathematical Sciences NTNU Norwegian University of Science and TechnologyN-7491 TrondheimNorway Department of mathematics University of OsloP.O.Box 1053BlindernN-0316 OsloNorway

The authors analyze continuity equations with Stratonovich stochasticity,■ρ+divh[ρo(u(t,x)+∑_(i=1)^(N)a_(i)(x)w_(i)(t))]=0defined on a smooth closed Riemannian manifold M with metric *** velocity field u is perturbed by Gaussian noise terms Wi(t),:WN(t)driven by smooth spatially dependent vector fields a1(x),...,aN(x)on *** velocity u belongs to L_(t)^(1)W_(x)^(1,2)with divh u bounded in Lf,for p>d+2,where d is the dimension of M(they do not assume div_(h) u∈L_(t,x)^(∞)).For carefully chosen noise vector fields ai(and the number N of them),they show that the initial-value problem is well-posed in the class of weak L^(2) solutions,although the problem can be ill-posed in the deterministic case because of concentration *** proof of this“regularization by noise”result is based on a L^(2) estimate,which is obtained by a duality method,and a weak compactness argument.

关键词： Stochastic continuity equation Riemannian manifold hyperbolic equa-tion Non-smooth velocity field Weak solution Existence Uniqueness

Biophotoelectrochemistry:An emerging frontier for channeling photoelectric effect into darkness zone of soils and sediments

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Pedosphere 2024年第1期34卷 5-8页

作者： Jie YE Shungui ZhOU kenneth h.NEALSON Christopher RENSING Fujian Provincial Key Laboratory of Soil Environmental health and Regulation College of Resources and EnvironmentFujian Agriculture and Forestry UniversityFuzhou 350002China Department of Earth Science University of Southern CaliforniaLos Angeles CA 90007USA

Solar energy captured by photosynthetic plants in the photic zone is recognized as the main driver for the formation of organic matter utilized by soil communities. however, the contribution of organic transformation to the linkage of solar energy and microbial metabolism of soils is reduced when the vadose zone is saturated. In contrast to the conventional biophotoelectrochemistry via photosynthesis with phytoplankton during the periodic saturation of soils, recent studies suggest that non-phototrophic microorganisms in soils and sediments are able to conduct light-dependent metabolism to sustain their functionality with photosensitizers under illumination. These interactions and processes utilize long-distance electron transfer networks to interconnect diverse electron transfer chains that channel photoexcited electrons into the opaque zone for soil communities. Such an emerging process not only allows for a better understanding of biogeochemical processes such as soil carbon sequestration and mitigation, but also shows great potential for environmental treatment such as the bioremediation of contaminated soils. Therefore, we suggest that biophotoelectrochemistry via photoelectric effect can have significant, heretofore unappreciated, theoretical and practical values.

关键词： soils soil metabolism

New Opportunities for Neutrons in Environmental and Biological Sciences

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Frontiers of Environmental Science & Engineering 2024年第7期18卷 179-186页

作者： Alexander Johs Shuo Qian Leighton Coates Brian h.Davison James G.Elkins Xin Gu Jennifer Morrell-Falvey hugh O'Neill Jeffrey M.Warren Eric M.Pierce kenneth herwig Oak Ridge National Laboratory Oak RidgeTN37831USA

The use of neutron methods in environmental and biological sciences is rapidly emerging and accelerating with the development of new instruments at neutron user *** article,based on a workshop held at Oak Ridge National Laboratory(ORNL),offers insights into the application of neutron techniques in environmental and biological *** highlight recent advances and identify key challenges and potential future research *** include soil and rhizosphere processes,root water dynamics,plant-microbe interactions,structure and dynamics of biological systems,applications in synthetic biology and enzyme engineering,next-generation bioproducts,biomaterials and bioenergy,nanoscale structure,and fluid dynamics of porous materials in *** provide an outlook on emerging opportunities with an emphasis on new capabilities that will be enabled at the Spallation Neutron Source Second Target Station currently under design at *** mission of scientific neutron user facilities worldwide is to enable science using state-of-the-art neutron *** aim to encourage researchers in the environmental and biological research community to explore the unique capability afforded by neutrons at these facilities.

关键词： Neutrons Environment Biology Neutron imaging Neutron scattering Second Target Station(STS)

Why ecosystem characteristics predicted from remotely sensed data are unbiased and biased at the same time-and how this affects applications

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Forest Ecosystems 2024年第1期11卷 24-31页

作者： Goran Ståhl Terje Gobakken Svetlana Saarela henrik J.Persson Magnus Ekstrom Sean P.healey Zhiqiang Yang Johan holmgren Eva Lindberg kenneth Nystrom Emanuele Papucci Patrik Ulvdal hans OleØrka Erik Næsset Zhengyang hou håkan Olsson Ronald E.McRoberts Department of Forest Resource Management Swedish University of Agricultural Sciences90183UmeåSweden Faculty of Environmental Sciences and Natural Resource Management Norwegian University of Life SciencesÅsNorway USDA Forest Service Rocky Mountain Research StationOgdenUTUSA The Key Laboratory for Silviculture and Conservation of Ministry of Education Beijing Forestry UniversityBeijing100083China Department of Forest Resources University of MinnesotaSt.PaulMNUSA

Remotely sensed data are frequently used for predicting and mapping ecosystem characteristics,and spatially explicit wall-to-wall information is sometimes proposed as the best possible source of information for ***,wall-to-wall information typically relies on model-based prediction,and several features of model-based prediction should be understood before extensively relying on this type of *** such feature is that model-based predictors can be considered both unbiased and biased at the same time,which has important implications in several areas of *** this discussion paper,we first describe the conventional model-unbiasedness paradigm that underpins most prediction techniques using remotely sensed(or other)auxiliary *** this point of view,model-based predictors are typically ***,we show that for specific domains,identified based on their true values,the same model-based predictors can be considered biased,and sometimes severely *** suggest distinguishing between conventional model-bias,defined in the statistical literature as the difference between the expected value of a predictor and the expected value of the quantity being predicted,and design-bias of model-based estimators,defined as the difference between the expected value of a model-based estimator and the true value of the quantity being *** show that model-based estimators(or predictors)are typically design-biased,and that there is a trend in the design-bias from overestimating small true values to underestimating large true ***,we give examples of applications where this is important to acknowledge and to potentially make adjustments to correct for the design-bias *** argue that relying entirely on conventional model-unbiasedness may lead to mistakes in several areas of application that use predictions from remotely sensed data.

关键词： Bias Model-based inference Design-based inference

Unequal Distribution of Innovation Efforts for Neglected Tropical Diseases: The Role of Funding Evaluation Criteria

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health 2024年第5期16卷 490-520页

作者： Anne M. G. Neevel kenneth D. S. Fernald Linda h. M. van de Burgwal Athena Institute Faculty of Science Vrije Universiteit Amsterdam Amsterdam Netherlands

Background: International research and innovation efforts for neglected tropical diseases have increased in recent decades due to disparities in overall health research funding in relation to global burden of disease. however, within the field of neglected tropical diseases some seem far more neglected than others. In this research the aim is to investigate the distribution of resources and efforts, as well as the mechanisms that underpin funding allocation for neglected tropical diseases. Methodology: A systematic literature review was conducted to establish a comprehensive overview of known indicators for innovation efforts related to a wide range of neglected tropical diseases. Articles were selected based on a subjective evaluation of their relevance, the presence of original data, and the breadth of their scope. This was followed by thirteen in-depth open-ended interviews with representatives of private, public and philanthropic funding organizations, concerning evaluation criteria for funding research proposals. Results: The findings reveal a large difference in the extent to which the individual diseases are neglected with notable differences between absolute and relative efforts. Criteria used in the evaluation of research proposals relate to potential impact, the probability of success and strategic fit. Private organizations prioritize strategic fit and economic impact;philanthropic organizations prioritize short-term societal impact;and public generally prioritize the probability of success by accounting for follow-up funding and involvement of industry. Funding decisions of different types of organizations are highly interrelated. Conclusions: This study shows that the evaluation of funding proposals introduces and retains unequal funding distribution, reinforcing the relative neglect of diseases. Societal impact is the primary rationale for funding but application of it as a funding criterion is associated with significant challenges. Furthermore, curre

关键词： Neglected Tropical Diseases Funding Decision Evaluation Criteria health Research Funding Research Impact

Long-term impact of artificial intelligence on colorectal adenoma detection in high-risk colonoscopy

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World Journal of Gastrointestinal Endoscopy 2024年第6期16卷 335-342页

作者： kenneth W Chow Matthew T Bell Nicholas Cumpian Maryanne Amour Ryan h hsu Viktor E Eysselein Neetika Srivastava Michael W Fleischman Sofiya Reicher Department of Medicine Harbor-UCLA Medical CenterTorranceCA 90502United States Department of Bioengineering Jacobs School of EngineeringUniversity of CaliforniaSan DiegoLa JollaCA 92093United States Department of Gastroenterology Harbor-UCLA Medical CenterTorranceCA 90502United States

BACKGROUND Improved adenoma detection rate(ADR)has been demonstrated with artificial intelligence(AI)-assisted ***,data on the real-world appli-cation of AI and its effect on colorectal cancer(CRC)screening outcomes is *** To analyze the long-term impact of AI on a diverse at-risk patient population undergoing diagnostic colonoscopy for positive CRC screening tests or *** AI software(GI Genius,Medtronic)was implemented into the standard proced-ure protocol in November *** was collected on patient demographics,procedure indication,polyp size,location,and *** screening outcomes were evaluated before and at different intervals after AI introduction with one year of *** We evaluated 1008 colonoscopies(278 pre-AI,255 early post-AI,285 established post-AI,and 190 late post-AI).The ADR was 38.1%pre-AI,42.0%early post-AI(P=0.77),40.0%established post-AI(P=0.44),and 39.5%late post-AI(P=0.77).There were no significant differences in polyp detection rate(PDR,baseline 59.7%),advanced ADR(baseline 16.2%),and non-neoplastic PDR(baseline 30.0%)before and after AI *** In patients with an increased pre-test probability of having an abnormal colonoscopy,the current generation of AI did not yield enhanced CRC screening metrics over high-quality *** the potential of AI in colonoscopy is undisputed,current AI technology may not universally elevate screening metrics across all situations and patient *** studies that analyze different AI systems across various patient populations are needed to determine the most effective role of AI in optimizing CRC screening in clinical practice.

关键词： Artificial intelligence Colonoscopy Adenoma detection rate Screening Colorectal adenoma

Endoscopic foregut surgery and interventions:The future is *** state-of-the-art and my personal journey

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World Journal of Gastroenterology 2019年第1期25卷 1-41页

作者： kenneth J Chang h.h.Chao Comprehensive Digestive Disease Center University of CaliforniaIrvine Medical CenterOrangeCA 92868United States

In this paper, I reviewed the emerging field of endoscopic surgery and present data supporting the contention that endoscopy can now be used to treat many foregut diseases that have been traditionally treated surgically. Within each topic,the content will progress as follows: "lessons learned", "technical considerations"and "future opportunities". Lessons learned will provide a brief background and update on the most current literature. Technical considerations will include my personal experience, including tips and tricks that I have learned over the ***, future opportunities will address current unmet needs and potential new areas of development. The foregut is defined as "the upper part of the embryonic alimentary canal from which the pharynx, esophagus, lung, stomach, liver,pancreas, and part of the duodenum develop". Foregut surgery is well established in treating conditions such as gastroesophageal reflux disease(GERD), achalasia, esophageal diverticula, Barrett's esophagus(BE) and esophageal cancer, stomach cancer, gastric-outlet obstruction, and obesity. Over the past decade, remarkable progress in interventional endoscopy has culminated in the conceptualization and practice of endoscopic foregut surgery for various clinical conditions summarized in this paper. Regarding GERD, there are now several technologies available to effectively treat it and potentially eliminate symptoms, and the need for long-term treatment with proton pump *** the first time, fundoplication can be performed without the need for open or laparoscopic surgery. Long-term data going out 5-10 years are now emerging showing extended durability. In respect to achalasia, per-oral endoscopic myotomy(POEM) which was developed in Japan, has become an alternative to the traditional heller's myotomy. Recent meta-analysis show that POEM may have better results than heller, but the issue of post-POEM GERD still needs to be addressed. There is now a resurgence of endoscopic tre

关键词： Endoscopy Foregut diseases Gastroesophageal reflux disease Endoscopic sleeve gastroplasty Endoscopic submucosal dissection Per-oral endoscopic myotomy Endo-hepatology

Membrane-based treatment of shale oil and gas wastewater:The current state of knowledge

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Frontiers of Environmental Science & Engineering 2019年第4期13卷 5-21页

作者： Tiezheng Tong kenneth h. Carlson Cristian A. Robbins Zuoyou Zhang Xuewei Du Department of Civil and Environmental Engineering Colorado State UniversityFort CollinsCO 80523USA

Shale oil and gas exploitation not only consumes substantial amounts of freshwater but also generates large quantities of hazardous wastewater. Tremendous research efforts have been invested in developing membrane-based technologies for the treatment of shale oil and gas wastewater. Despite their success at the laboratory scale, membrane processes have not been implemented at full scale in the oil and gas fields. In this article, we analyze the growing demands of wastewater treatment in shale oil and gas production, and then critically review the current stage of membrane technologies applied to the treatment of shale oil and gas wastewater. We focus on the unique niche of those technologies due to their advantages and limitations, and use mechanical vapor compression as the benchmark for comparison. We also highlight the importance of pretreatment as a key component of integrated treatment trains, in order to improve the performance of downstream membrane processes and water product quality. We emphasize the lack of sufficient efforts to scale up existing membrane technologies, and suggest that a stronger collaboration between academia and industry is of paramount importance to translate membrane technologies developed in the laboratory to the practical applications by the shale oil and gas industry.

关键词： Shale oil and gas production Wastewater treatment and reuse Membrane technology Pretreatment Academia-industry collaboration

Transport and humification of dissolved organic matter within a semi-arid floodplain

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Journal of Environmental Sciences 2017年第7期29卷 24-32页

作者： Wenming Dong Jiamin Wan Tetsu K.Tokunaga Benjamin Gilbert kenneth h.Williams Earth and Environment Sciences Area Lawrence Berkeley National LaboratoryBerkeleyCA 94720USA

In order to understand the transport and humification processes of dissolved organic matter（DOM） within sediments of a semi-arid floodplain at Rifle,Colorado,fluorescence excitation–emission matrix（EEM） spectroscopy,humification index（hIX） and specific UV absorbance（SUVA） at 254 nm were applied for characterizing depth and seasonal variations of DOM *** revealed that late spring snowmelt leached relatively fresh DOM from plant residue and soil organic matter down into the deeper vadose zone（VZ）.More humified DOM is preferentially adsorbed by upper VZ sediments,while non-or lesshumified DOM was transported into the deeper ***,DOM at all depths undergoes rapid biological humification process evidenced by the products of microbial by-product-like（i.e.,tyrosine-like and tryptophan-like） matter in late spring and early summer,particularly in the deeper VZ,resulting in more humified DOM（e.g.,fulvic-acid-like and humic-acid-like substances） at the end of *** indicates that DOM transport is dominated by spring snowmelt,and DOM humification is controlled by microbial degradation,with seasonal *** is expected that these relatively simple spectroscopic measurements（e.g.,EEM spectroscopy,hIX and SUVA） applied to depth-and temporally-distributed pore-water samples can provide useful insights into transport and humification of DOM in other subsurface environments as well.

关键词： Dissolved organic matter Transport humification Semi-arid Fluorescence excitation-emission matrix