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Atrazine removal from water by activated charcoal cloths

International Soil and Water Conservation Research 2020年第2期8卷 205-212页

作者： j.vier M.Gonzalez Lynnette R.Murphy chad j.penn Veera M.Boddu Laura L.Sanders National Soil Erosion Research Laboratory USDA-ARSWest LafayetteIN47907USA Earth Science Department Northeastern Illinois UniversityChicagoIL60625USA O’Neill School of Public and Environmental Affairs University of IndianaBloomingtonIN47405USA Plant Polymer Research Unit National Center for Agriculture Utilization ResearchUSDA-ARSPeoriaIL61604USA

Pollution control structures may be adapted to enhance the removal of nutrients and pesticides from water. Charcoal-like material is known to sorb organic compounds in solution, including atrazine, a herbicide used to control broadleaf weeds, which persists in soils and can migrate from soils to water bodies, ultimately affecting water quality. The primary goal of this study was to investigate if activated charcoal cloths (single-weave, SW;double-weave, DW;and knitted, KT) are more efficient to remove atrazine from aqueous solutions than a cloth without activated charcoal (control) currently used in pollution control structures. The approach consisted of sorption kinetics, flow-through, and desorption/degradation experiments using 50 and 1000μg L-1 atrazine solutions. Results showed that within 30 min of contact time, the control sorbed from 22.6 to 36.1% of atrazine in solution;whereas the activated charcoal cloths sorbed from 76 to 99% of atrazine in solution (SW > KT > DW). The flow-through ex-periments showed that the SW sorbed 88.2, 76.1, and 52.2%of atrazine at the contact time of 0.75, 5, and 10 min, respectively. After 28 days of incubation, previously sorbed atrazine on the SW cloth did not degrade and <2.0% was desorbed. The results showed that activated charcoal cloths are a practical alternative for improving atrazine removal in water in pollution control structures.

关键词： Atrazine Activated charcoal Water quality Pesticide Cloth

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Predicting Phosphorus Sorption onto Steel Slag Using a Flow-through approach with Application to a Pilot Scale System

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j.urnal of Water Resource and Protection 2011年第4期3卷 235-244页

作者： chad j. penn j.shua M. McGrath 不详

Reducing phosphorus (P) loads from soils to surface waters is necessary for solving the problem of eutrophication. Many industrial by-products have been shown to sorb appreciable amounts of dissolved P from solution and it has been proposed to use P sorption materials (PSMs) such as steel slag in landscape scale “filters” for trapping dissolved P in runoff. The obj.ctive of this study was to model the effect of retention time (RT) and P concentration on P sorption by steel slag and a surface modified slag in a flow-through system. Sorption of P onto steel slag and rej.venated-modified steel slag was measured using a traditional batch isotherm and a flow-through setting at several RTs and P concentrations. Flow-through data were used to produce a model that estimated P sorption based on RT and P concentration. The model was tested on a pilot-scale pond filter consisting of the same slag materials. For both the materials, flow-through tests indicated an increase in RT increased P removal efficiency but decreased the total amount of P removed at saturation. The Langmuir model developed from batch isotherms overestimated and underestimated P sorption in normal and rej.venated slag respectively, relative to flow-through. Normal and rej.venated slag removed 38 and 36% of P in the pilot-scale pond filter after 2 weeks of pumping. The Langmuir equation poorly predicted P sorption in the pond filter while the flow-through model produced reasonable estimates. Results suggest that flow-through methodology is necessary for estimating P sorption in the context of landscape P filters.

关键词： Phosphorus By-Products Phosphorus Removal Structure

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Land application of spent gypsum from ditch filters: phosphorus source or sink?

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Agricultural Sciences 2011年第3期2卷 364-374页

作者： Karen L. Grubb j.shua M McGrath chad j. penn Ray B. Bryant Department of Environmental Science and Technology University of Maryland College Park PA USA Department of Plant and Soil Sciences Oklahoma State University Stillwater USA USDA-Agricultural Research Service College Park PA USA USDA-National Institute of Food and Agriculture Washington D.C. USA

Agricultural drainage ditches can provide a direct connection between fields and surface waters, and some have been shown to deliver high loads of phosphorus (P) to sensitive water bodies. A potential way to reduce nutrient loads in drainage ditches is to install filter structures containing P sorbing materials (PSMs) such as gypsum to remove P from ditch flow. The obj.ctive of this study was to determine the effect of land-application of gypsum removed from such filters on soil P forms and concentrations. Gypsum was saturated at two levels on a mass basis of P and applied to two soils of contrasting texture, a silt loam and a sandy loam and applied at both a high and low rate. The treated soils were incubated in the laboratory at 25oC, and samples were collected at 1, 7, and 119 days after initiation. Soil type, time after application, gypsum rate, and P saturation level all had a significant impact on soil P forms and concen-trations. However, it appears that land application of spent filter gypsum at realistic rates would have little effect on soluble P concentrations in amended soils.

关键词： Phosphorus Sorbing Materials Gypsum Ditch Filter

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Predictors of the placebo response in a nutraceutical randomized controlled trial for depression

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j.urnal of Integrative Medicine 2024年第1期22卷 46-53页

作者： Rosemary Arnold j.nifer Murphy-Smith Chee H.Ng David Mischoulon Gerard j.Byrne chad A.Bousman Con Stough Michael Berk j.rome Sarris Professorial Unit the Melbourne ClinicDepartment of PsychiatryUniversity of MelbourneRichmond 3121Australia Depression Clinical and Research Program Department of PsychiatryMassachusetts General HospitalHarvard Medical SchoolBostonMA 02115USA Faculty of Medicine Discipline of PsychiatryCentre for Clinical ResearchRoyal Brisbane&Women’s HospitalHerstonthe University of QueenslandBrisbane 4006Australia Departments of Medical Genetics PsychiatryPhysiology&Pharmacology and Community Health SciencesUniversity of CalgaryCalgaryAB T2N 1N4Canada Department of Psychiatry the University of MelbourneMelbourne 3052Australia Centre for Human Psychopharmacology Swinburne UniversityMelbourne 3122Australia The Institute for Mental and Physical Health and Clinical Translation School of MedicineBarwon HealthDeakin UniversityGeelong 3220Australia The Centre of Excellence in Youth Mental Health the University of MelbourneParkville 3052Australia Florey Institute of Neuroscience and Mental Health the University of MelbourneParkville 3052Australia NICM Health Research Institute Western Sydney UniversityWestmeadNSW 2145Australia

Obj.ctive The placebo response in depression studies is the change in symptoms amongst those who receive an inactive *** well-designed randomized controlled trials(RCTs)of depression have a high proportion of placebo responders,with little understanding as to *** present study assesses characteristics associated with the placebo response in a nutraceutical trial with a large proportion of placebo *** This is a secondary analysis of a nutraceutical depression RCT which identified no overall treatment benefit relative to placebo(n=69 in placebo group).We investigated participant characteristics such as socio-demographics,clinical features,and recruitment methods,and their association with the placebo *** genetic polymorphisms were also *** response was measured based on change in Montgomery-Asberg Depression Rating Scale *** association of these hypothesis-driven variables of interest and the placebo response was examined using linear mixed effects *** Greater levels of education,particularly pursuing post-high school education,better self-reported general health,marriage/de facto,greater improvement in the first trial week,and more failed antidepressant therapies in the current depressive episode were associated with greater placebo *** increased placebo response was not found in those recruited via social media nor in those with concomitant antidepressant *** nucleotide polymorphisms from the tryptophan hydroxylase 1(TPH1)gene(A779C and A218C)were weakly associated with greater placebo response,although the evidence was attenuated after accounting for multiple *** This is,to our knowledge,the first study within nutraceutical research for depression to assess the association between participant characteristics and variation in the placebo *** variables appeared to predict the placebo *** findings may encourage future trial design

关键词： Randomized controlled trial Placebo Depression Nutraceutical Psychiatry

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Intramedullary bone pedestal formation contributing to femoral shaft fracture nonunion:A case report and review of the literature

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World j.urnal of Orthopedics 2022年第5期13卷 528-537页

作者： Charles B Pasque Alexander j.Pappas chad A Cole j. Department of Orthopaedic Surgery and Rehabilitation University of Oklahoma College of MedicineOklahoma CityOK 73104United States University of Colorado School of Medicine AuroraCO 80045United States

BACKGROUND Femoral shaft fracture is a commonly encountered orthopedic inj.ry that can be treated operatively with a low overall delayed/nonunion *** the case of delayed union after antegrade or retrograde intramedullary nail fixation,fracture dynamization is often attempted *** after dynamization has been shown to occur due to infection and other aseptic *** present a unique case of diaphyseal femoral shaft fracture nonunion after dynamization due to intramedullary cortical bone pedestal formation at the distal tip of the *** SUMMARY A 37-year-old male experienced a high-energy trauma to his left thigh after coming down hard during a motocross *** was consistent with an isolated,closed,left mid-shaft femur *** was initially managed with reamed antegrade intramedullary nail fixation but had continued thigh *** at four months demonstrated no evidence of fracture union and failure of the distal locking screw,and dynamization by distal locking screw removal was *** patient continued to have pain eight months after the initial procedure and 4 mo after dynamization with serial radiographs continuing to demonstrate no evidence of fracture *** decision was made to proceed with exchange nailing for aseptic fracture *** the exchange procedure,an obstruction was encountered at the distal tip of the failed nail and was confirmed on magnified fluoroscopy to be a pedestal of cortical bone in the *** obstruction required further distal reaming.A longer and larger diameter exchange nail was placed without difficulty and without a distal locking screw to allow for dynamization at the fracture ***-operative radiographs showed proper fracture and hardware *** was subsequently radiographic evidence of callus formation at one year with subsequent fracture consolidation and resolution of thigh pain at eighteen *** The risk of fracture nonunion caused by int

关键词： Nonunion Femoral shaft fracture Diaphysis Fracture fixation Antegrade intramedullary nail Case report

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Covering Your Bases： Inheritance of DNA Methylation in Plant Genomes

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Molecular Plant 2014年第3期7卷 472-480页

作者： chad E. Niederhuth Robert j. Schmitz Department of Genetics University of Georgia Athens GA 30602 USA

Cytosine methylation is an important base modification that is inherited across mitotic and meiotic cell divisions in plant genomes. Heritable methylation variants can contribute to within-species phenotypic variation. Few methylation variants were known until recently, making it possible to begin to address maj.r unanswered questions： the extent of natural methylation variation within plant genomes, its effects on phenotypic variation, its degree of depend- ence on genotype, and how it fits into an evolutionary context. Techniques like whole-genome bisulfite sequencing （WGBS） make it possible to determine cytosine methylation states at single-base resolution across entire genomes and populations. Application of this method to natural and novel experimental populations is revealing answers to these long-standing questions about the role of DNA methylation in plant genomes.

关键词： DNA methylation epigenetics epiallele whole-genome bisulfite sequencing.

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Evaluating a Three-Fold Continuum of Fry Stocking Density for Rearing Walleye in Lined Ponds

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Open j.urnal of Animal Sciences 2022年第2期12卷 192-199页

作者： Matthew j. Ward chad R. Haabala South Dakota Department of Game Fish and Parks Blue Dog State Fish Hatchery Waubay USA

Fry stocking density can affect harvest metrics for fingerling walleye (Stizostedion vitreum) reared in drainable ponds, but few studies have examined these relationships with the use of elevated walleye fry stocking densities in lined ponds. Correlation and regression analyses were used to assess how a three-fold change in walleye fry stocking density (234,375 to 703,125 per hectare) relates to harvest metrics and length of the culture period, as well as the tradeoff experienced between walleye size (grams) and harvest density in 0.32-hectare lined ponds over a nine-year period at Blue Dog State Fish Hatchery, South Dakota. As fry stocking density increased, so did harvest metrics for both number (r = 0.85, P < 0.01) and yield (r = 0.81, P < 0.01). Length of the culture period varied between 24 and 35 days and was negatively related to stocking density (r = -0.66, P The linear relationship between harvest density and yield was highly correlated (r = 0.95, P < 0.01) with highest values measuring 617,625 walleye and 173 kilograms per hectare. Harvest density explained 61% of the variation in walleye size (P 0.01) and exhibited a decreasing curvilinear relationship such that continued increases in harvest density resulted in smaller reductions in fish size. Increasing fry stocking density from 234,375 to 703,125 per hectare in lined ponds coincided with increased rearing efficiencies for number and yield, as well as a reduced culture period. Minimal reduction in walleye size occurred once harvest density exceeded 300,000 per hectare.

关键词： Walleye Culture Lined Ponds Rearing Efficiencies Pond Stocking Density

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Material transport in dip-pen nanolithography

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Frontiers of physics 2014年第3期9卷 385-397页

作者： Keith A. Brown Daniel j. Eichelsdoerfer Xing Liao Shu He chad A. Mirkin Department of Chemistry Northwestern University 2145 Sheridan Road Evanston IL 60208 USA International Institute for Nanotechnology Northwestern University 2145 Sheridan Road Evanston IL 60208 USA Department of Materials Science and Engineering Northwestern University 2145 Sheridan Road Evanston IL 60208 USA

Dip-pen *** （DPN） is a useful method for directly printing materials on surfaces with sub-50nm resolution. Because it, involves the physical transport of materials from a scanning probe tip to a surface and the subsequent chemical interaction of that material with the surface, there are many factors to consider when attempting to understand DPN. In this review, we overview the physical and chemical processes that are known to play a role in DPN, Through a detailed review of the literature, we classify inks into three general categories based on their transport properties, and highlight the myriad ways that. DPN can be used to perform chemistry at the tip of a scanning probe.

关键词： dip-pen nanolithography scanning probe lithography materials transport

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A preliminary evaluation of throughfall sampling techniques in a mature coniferous forest

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j.urnal of Forestry Research 2014年第2期25卷 407-413页

作者： Darryl. E. Carlyle-Moses chad. E. Lishman Adam. j. McKee Department of Geography & Environmental Studies Thompson Rivers University Graduate Program in Environmental Science Thompson Rivers University

Rainfall, throughfall and stemflow were measured and canopy interception loss was derived for 14 rainfall events from j.ne 22 to August 30, 2008 within a mature declining hybrid white spruce （Picea glauca （Moench） Voss x p engelmannii Parry ex Engelm.） - subalpine fir （Abies lasiocarpa （Hook.） Nutt.） - lodgepole pine （Pinus contorta vat. latifolia Dougl. ex Loud.） stand in south-central British Columbia, Can- ada. Stemflow was negligible during the study period, while, respectively throughfall and canopy interception loss accounted for approximately 59.4% and 40.6% of the 50.1 mm of cumulative rainfall. Throughfall variability was assessed with three approaches involving roving and stationary wedge-type gauges, and stationary trough gauges. Throughfall exhibited large spatial variability with the coefficient of variability of study period throughfall sampled using 16 stationary trough gauges being 30.3%, while it was 38.0% and 28.7% for 32 stationary and 32 roving wedge gauges, respectively. Our analysis suggests that a roving gauge method is better than a stationary approach since the errors associated with event mean throughfalls are summed quadratically and a greater portion of the canopy area is sampled. Trough gauges were more efficient than wedge gauges; however, this efficiency was less than expected given their much larger sampling areas, suggesting that spatial autocorrelation lengths of throughfall may be longer than the trough systems. The spatial distribution of throughfall showed a high degree of temporal persistence throughout the study suggesting the existence of stable ＂wet＂ and ＂dry＂ inputs to the floors of these coniferous forests.

关键词： throughfall canopy interception loss stemflow spatial variability temporal persistence

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Insights into the role of j.smonic acid-mediated defenses against necrotrophic and biotrophic fungal pathogens

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Frontiers in Biology 2012年第1期7卷 48-56页

作者： Christopher j. ANTICO chad COLON Taylor BANKS Katrina M. RAMONELL Department of Biological Sciences University of Alabama Tuscaloosa AL 35487 USA

j.smonic acid （j.） is a natural hormone regulator involved in development, responses against woundingand pathogen attack. Upon perception of pathogens, j. is synthesized and mediates a signaling cascade initiating various defense responses. Traditionally, necrotrophic fungi have been shown to be the primary activators of j.- dependent defenses through the j.-receptor, COIl. Conversely, plants infected with biotrophic fungi have classically been associated with suppressing j.-mediated responses. However, recent evidence has shown that certain biotrophic fungal species also trigger activation of j.-mediated responses and mutants deficient in j. signaling show an increase in susceptibility to certain biotrophic fungal pathogens. These findings suggest a new role for j. in defense against fungal biotrophs. This review will focus on recent research advancing our knowledge of j.-dependant responses involved in defense against both biotrophic and necrotrophic fungi.

关键词： j.smonic acid (j.) methyl j.smonate (Mej.) biotrophic fungi necrotrophic fungi COIl

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