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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

A Comparative Study of the Economic Feasibility of Employing CHP Systems in Different Industrial Manufacturing Applications

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Energy and Power Engineering 2011年第5期3卷 630-640页

作者： chad A. Wheeley Pedro j. Mago Rogelio Luck 不详

Extensive research work including multiple methodologies and numerous simulations have been completed in order to determine the economic effectiveness of employing CHP at commercial and residential sites. In contrast to the above, very few attempts have been made to develop methodologies to study the feasibility of CHP systems at industrial manufacturing facilities. As a result, practical opportunities for CHP at industrial sites are often not realized or even investigated. It follows that there is a need in the CHP related literature for an analysis that is explicit and yet general enough to determine the economic viability and potential for success of CHP systems at industrial manufacturing facilities. Therefore, the purpose of this paper is to clearly outline a methodology to determine the economic effectiveness of installation and operation of a CHP system at industrial facilities that have a need for space or process heating in the form of steam. The effect on the CHP system economic performance of several parameters, such as the proj.ct payback, internal rate of return, net present value, etc., are considered in the proposed methodology. The applicability and generality of the methodology is illustrated by examples including four different manufacturing facilities. The effects of the variability of factors such as annual facility operational hours during which both process heat and electricity are needed, facility average hourly thermal load, cost of utility supplied electricity, and CHP fuel type and associated fuel cost, on the outcome of the economic analysis are also examined.

关键词： CHP Systems CHP For Industrial Manufacturing Facilities Economic Feasibility Study

Genetic Diversity in the Environmental Conditioning of Two Sorghum (<i>Sorghum bicolor</i>L.) Hybrids

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American j.urnal of Plant Sciences 2018年第4期9卷 817-831页

作者： j.hn j. Burke Yves Emendack chad Hayes j.nping Chen USDA-ARS PA Cropping Systems Research Laboratory Lubbock TX USA

Sorghum metabolism continually adapts to environmental temperature as thermal patterns modulate diurnally and seasonally. The degree of adaptation to any given temperature may be difficult to determine from phenotypic responses of the plants. The present study was designed to see if the efficiency of quantum yield of photosystem II could be used as a measure of how well leaf tissue metabolism was able to withstand a prolonged respiratory demand caused by elevated temperatures. The efficiency of quantum yield values of Pioneer 84G62 and Northrup King KS585 commercial sorghum hybrids showed that when the hybrids were grown in a 28°C/20°C day/night cycle in the greenhouse or the field, Pioneer hybrid 84G62 withstood subsequent elevated thermal challenges better than Northrup King KS585. The same hybrids grown in a 39°C/32°C day/night cycle showed similar efficiency of quantum yield values when thermally challenged. Water-deficit stress increased the heat resistance of the tissue raising the efficiency of quantum yield of both lines to the same level. Upon recovery from the water deficit stress the differential efficiency of quantum yield values between the two lines re-appeared. The data provided in this study suggest a metabolic advantage of Pioneer 84G62 to environmental thermal challenges compared with the Northrup King KS585.

关键词： Sorghum Sorghum bicolor L. Thermal Sensitivity Adaptation

SAR of tricyclic sulfones as γ-secretase inhibitors

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Science China Chemistry 2011年第11期54卷 1688-1701页

作者： COLE David ASBEROM Ted BARA Tom BENNETT chad BURNETT Duane A. CLADER j.hn DOMALSKI Martin GREENLEE William j. HYDE Lynn j.SIEN Hubert McBRIAR Mark McKITTRICK Brian PISSARNITSKI Dmitri RAj.GOPALAN Murali SASIKUMAR Thavalakulamgara Merck Research Laboratories 2015 Galloping Hill RoadKenilworth New Jersey 07033 USA

Novel tricyclic sulfones as γ-secretase inhibitors have been reported by this laboratory for the treatment of Alzheimer's disease. Compounds in this series have comparable or better in vitro activities and in vivo efficacies than sulfonamide analogues re- ported previously by this laboratory. Based on the previously reported tricyclic sulfone scaffold, additional SAR studies of C ring were carried out. Various C-ring structures including cyclohexane, pyran, and piperidine were tolerated. Additionally, the 7- and 8- positions of the C-ring were identified as the best sites to introduce substituent for modulating the pharmacokinetic properties of compounds from this series.

关键词： tricyclic sulfones T-secretase Alzheimer's disease inhibitors

Changing the paradigm：the potential for targeted therapy in laryngeal squamous cell carcinoma

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Cancer Biology & Medicine 2016年第1期13卷 87-100页

作者： Megan L.Ludwig Andrew C.Birkeland Rebecca Hoesli Paul Swiecicki Matthew E.Spector j.chad Brenner Department of Otolaryngology Head and Neck SurgeryUniversity of Michigan Medical SchoolAnn ArborMI 48109USA Cellular and Molecular Biology Program University of MichiqanAnn ArborMI 48109USA Department of Hematology Oncology University of Michigan Medical SchoolAnn ArborMI 48109USA Comprehensive Cancer Center University of Michigan Medical SchoolAnn ArborMI 48109USA

Laryngeal squamous cell carcinoma(LSCC) remains a highly morbid and fatal disease. Historically, it has been a model example for organ preservation and treatment stratification paradigms. Unfortunately, survival for LSCC has stagnated over the past few decades. As the era of next-generation sequencing and personalized treatment for cancer approaches, LSCC may be an ideal disease for consideration of further treatment stratification and personalization. Here, we will discuss the important history of LSCC as a model system for organ preservation, unique and potentially targetable genetic signatures of LSCC, and methods for bringing stratified, personalized treatment strategies to the 21^(st) century.

关键词： Head and neck cancer laryngeal squamous cell carcinoma genetics targeted therapy personalized medicine

Rapid Lab-Scale Microwave-Assisted Extraction and Analysis of Anthropogenic Organic Chemicals in River Sediments

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International j.urnal of Geosciences 2011年第3期2卷 267-273页

作者： Thomas j.Brown chad A Kinney 不详

An Ethos EZ Microwave Lab Station is employed in the development of a robust and efficient microwave extraction method for organic contaminants of anthropogenic origin in river sediments. The extraction method is designed for a small, representative set of target compounds encompassing a range of physicochemical properties. Listed in order of gas chromatography elution they are para-cresol, indole, 4-tert-octylphenol, phenanthrene, triclosan, bisphenol-A, carbamazepine, and benzo [a] pyrene. The sediments samples are extracted wet, which reduces preparation time, and allows the ambient moisture of the sediments to aid in microwave energy absorption and the extraction process. The microwave can hold up to 12 samples that can be simultaneously extracted allowing for rapid sample preparation. Utilizing the pressurized vessels, microwave energy, and a unique mixture of three organic solvents allows for multiple samples to be extracted rapidly with minimal solvent consumption. The final extracts are quantified by gas chromatography/mass spectrometry. Recoveries of the 8 target compounds in sediment range from 49% to 113%, and method detection limits range between 14 and 114 μg kg–1, which are comparable with other more time consuming methods.

关键词： Microwave Assisted Extraction Para-Cresol Phenanthrene Bisphenol-A Triclosan Ben-zo[a]pyrene

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

The substorm current wedge and midnight sector partial ring current near substorm onset: A synthesis based on a magnetotail magnetic field geometry model

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Advances in Polar Science 2013年第1期24卷 32-41页

作者： George j.Sofko Kathryn A McWilliams chad R Bryant Institute of Space & Atmospheric Studies University of Saskatchewan

The Substorm Current Wedge （SCW） occurrence in the late growth and onset phases of substorms was proposed as the current system which disrupts cross-tail current by diverting it to the ionosphere. The closure current for the SCW originally was suggested to be the strong westward auroral electroj.t （WEj.. However, the SCW-WEj.system has no viable generator current. Similarly, the asymmetric or Partial Ring Current （PRC） increases in strength during the growth phase, and is sometimes associated with an enhanced Region 2 field-aligned current （FAC） closing to the ionosphere, but specifics of that closure have been lacking. Here we present a tmifying picture which includes the SCW post- and pre-midnight （AM and PM, respectively） currents and a generator current in the midnight portion of the PRC system, with these currents based upon a model of the nightside magnetotail magnetic geometry. That geometry consists of open north and south lobe regions surrounding a plasmasheet with two types of closed field line regions-stretched lines in the central part of the plasmasheet （SPS） and dipolar lines （DPS） between the low lati- tude boundary layer （LLBL） regions and the SPS. There is also an important plasmasheet transition region （TPS） in which the dipolar field near the plasmapause gradually transforms to stretched lines near the earthward edge of the SPS, and in which the midnight part of the PRC flows. We propose that our proposed near-onset current system consists of a central current which be- comes part of the midnight sector PRC and which is the generator, to which are linked two three-part current systems, one on the dawnside and one on the duskside. The three-part systems consist of up and down FACs closing as Pedersen currents in the iono- sphere. These 3-part systems are not activated until near-onset is reached, because of a lack of ionospheric conductivity in the appropriate locations where the Pedersen current closure occurs. The initial downward FAC of the 3-pa

关键词： magnetotail magnetic field model auroral substorm substorm current wedge partial ring current substorm onset

Dynamic Modelling of a Hybrid Variable Reluctance Machine Using the 3D Finite Element Method

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j.urnal of Electromagnetic Analysis and Applications 2024年第7期16卷 103-113页

作者： Dingamadj. Hilaire Belemdara j.rôme Mbaïnaïbeye Department of Physics and Engineering Sciences University of NDjamena NDjamena Chad Department of Physics University of Moundou Moundou Chad

This paper presents the work carried out to evaluate the dynamic performance of the Hybrid Variable Reluctance Motor (HVRM). The fourth-order Runge-Kutta integration algorithm was employed to solve the equations of the dynamic model, in conj.nction with the three-dimensional finite element method. The 3D numerical data was calculated using Comsol Multiphysics, which accounts for the nonlinearity of the ferromagnetic material and the 3D nature of the HVRM. The outcomes of this study are precise and accurately predict the dynamic behaviour of the HVRM in terms of rotor position response, rotational speed and torque. The distinctive contribution of this work lies in the 3D numerical modelling of the HVRM and the subsequent evaluation and analysis of its dynamic operation. Analytical and numerical 2D studies are less resource-intensive and time-consuming, and are more straightforward and rapid to analyse and interpret. However, they are constrained in their capacity to examine spatial, volumetric interactions and intricate dynamics such as flux studies where three 3D effects cannot be disregarded, winding end effects and the configuration and positioning of the interposed permanent magnet.

关键词： Numerical Computing Complex Dynamic Flux Linkage 3D Effects Equilibrium Position

Assessing the academic achievement of United States orthopaedic departments

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World j.urnal of Orthopedics 2022年第2期13卷 201-211页

作者： Rishi Trikha Thomas E Olson Ameen Chaudry chad R Ishmael Cristina Villalpando Clark j.Chen Kellyn R Hori Nicholas M Bernthal Department of Orthopaedic Surgery University of CaliforniaLos AngelesCA 90404United States Department of Orthopaedic Surgery David Geffen School of Medicine at UCLALos AngelesCA 90095United States

BACKGROUND Assessing academic productivity allows academic departments to identify the strengths of their scholarly contribution and provides an opportunity to evaluate areas for *** To provide obj.ctive benchmarks for departments seeking to enhance academic productivity and identify those with significant improvement in recent *** Our study retrospectively analyzed a cohort of orthopaedic faculty at United States-based academic orthopaedic programs.5502 full-time orthopaedic faculty representing 178 programs were included in *** included for analysis were National Institutes of Health funding(2014-2018),leadership positions in orthopaedic societies(2018),editorial board positions of top orthopaedic j.urnals(2018),total number of publications and Hirsch-index.A weighted algorithm was used to calculate a cumulative score for each academic *** study was performed at a large,United States medical *** All 178 programs included in analysis were evaluated using the comprehensive weighted *** five institutions with the highest cumulative score,in decreasing order,were:Washington University in ***,the Hospital for Special Surgery,Sidney Kimmel Medical College(SKMC)at Thomas j.fferson University,the University of California,San Francisco(UCSF)and Massachusetts General Hospital(MGH)/Brigham and Women’s/*** five institutions with the highest score per capita,in decreasing order,were:Mayo Clinic(Rochester),Washington University in ***,Rush University,Virginia Commonwealth University(VCU)and MGH/Brigham and Women’s/*** five academic programs that had the largest improvement in cumulative score from 2013 to 2018,in decreasing order,were:VCU,SKMC at Thomas j.fferson University,UCSF,MGH/Brigham and Women’s/Harvard,and Brown *** This algorithm can provide orthopaedic departments a means to assess academic productivity,monitor progress,and identify areas for improvement as th

关键词： Bibliometrics Academic achievement Number of publications National Institutes of Health funding Hirsch-index