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SSRN 2023年

作者： Chen, Siying Wang, Xiaohong Ye, Xiaolin Qin, Yingju Wang, Haiqing Liang, Zhenda Zhu, Lishan Zhou, Li Martyniuk, Christopher J. Yan, Bing Institute of Environ. Res. at Greater Bay Area Key Laboratory for Water Quality and Conservation of the Pearl River Delta Ministry of Education Guangzhou University Guangzhou510006 China Center for Environmental and Human Toxicology Department of Physiological Sciences College of Veterinary Medicine UF Genetics Institute Interdisciplinary Program in Biomedical Sciences in Neuroscience University of Florida GainesvilleFL32611 United States School of Environmental Science and Engineering Shandong University Shandong Jinan250100 China

Rare earth elements (REEs) are exploited for global use in manufacturing. Such activities result in their release into the environ.ent and the transformation into more stable phosphate deposition. The objective of this study was to evaluate molecular and behavioral changes of zebrafish exposed to the synthesized terbium phosphate (TbPO4) at concentrations of 10, 20, and 50 mg/L and to determine its potential for neurotoxicity. Metabolomic profiling and assessment of transcripts and proteins were conducted to uncover the molecular mechanisms underlying TbPO4 with emphasis on neurotransmitter systems. Exposure to 20 mg/L TbPO4 induced larval hyperactivity and perturbed the cholinergic system in zebrafish. Based on metabolomics, dopamine (DA), serotonin (5-HT), and many of their precursors and metabolites were decreased in abundance by TbPO4. In addition, the expression levels of transcripts related to the synthesis, transport, receptor binding, and metabolism of DA and 5-HT were analyzed at the mRNA and protein levels. Transcript and protein levels for tyrosine hydroxylase (TH), the rate-limiting enzyme for DA synthesis, were down-regulated in larval fish. Monoamine oxidase (MAO), an enzyme that catabolizes monoamines DA and 5-HT, also reduced mRNA abundance. We hypothesize that DA synthesis and monoamine metabolism are associated with behavioral alterations. In addition, a mechanism for the disruption of neurotransmitter systems by TbPO4 may be the apoptosis of neurons. This study elucidates putative mechanisms and exposure risks to wildlife and humans by characterizing phosphatic REE-induced neurotoxicity in developing zebrafish. © 2023, The Authors. All rights reserved.

关键词： Rare earth elements

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Fishery management and culling (multiple letters)

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science 2004年第5703期306卷 1891-1892页

作者： Corkeron, Peter J. Pikitch, Ellen K. Santora, Christine Babcock, Elizabeth Bakun, Andrew Bonfil, Ramon Conover, David Dayton, Paul Doukakis, Phaedra Fluharty, David Heneman, Burr Houde, Ed Livingston, Pat Mangel, Marc McAllister, Murdoch Pope, John Salnsbury, Keith Norwegian Inst. of Marine Research Pb 6404 N-9294 Tromsø Norway Pew Institute for Ocean Science Rosenstiel Sch. Mar. Atmosph. Sci. University of Miami 126 East 56th Street New York NY 10022 United States Pew Institute for Ocean Science RSMAS University of Miami 4600 Rickenbacker Causeway Miami FL 33149-1098 United States RSMAS University of Miami Miami FL 33149-1098 United States Wildlife Conservation Society 2300 Southern Boulevard Bronx NY 10460 United States Marine Sciences Research Center Stony Brook University Stony Brook NY 11794-5000 United States Scripps Institution of Oceanography San Diego CA 92093-0227 United States School of Marine Affairs University of Washington Seattle WA 98105 United States Commonweal Ocean Policy Program Bolinas CA 94924 United States University of Maryland Center for Environmental Science Chesapeake Biological Laboratory Solomons MD 20688 United States Alaska Fisheries Science Center Seattle WA 98115 United States Dept. of Appl. Math. and Statistics Jack Baskin School of Engineering University of California Santa Cruz CA 95064 United States Dept. of Environ. Sci. and Technol. Imperial College Royal School of Mines Building Prince Consort Road London SW7 2BP United Kingdom National Research Council Ltd. Norfolk NR34 OBT United Kingdom Division of Marine Research CSIRO Hobart Tasmania 7001 Australia

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A longitudinal study of student persistence in science, technology, engineering, and mathematics (STEM) at a regional urban university

A longitudinal study of student persistence in science, tech...

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2003 ASEE Annual Conference and Exposition: Staying in Tune with engineering Education

作者： Della-Piana, Connie Kubo Darnell, Ann Bader, Julia Romo, Lilly Rubio, Nohemi Flores, Benjamin Knaust, Helmut Brady, Thomas Swift, Andrew Model Institutions for Excellence University of Texas El Paso Model Inst. Excellence Initiative University of Texas El Paso Statistical Consulting Laboratory University of Texas El Paso Department of Electrical Engineering UTEP NSF Model Institutions Excellence Program Entering Students Prog. Sci./Eng. UTEP Department of Mathematics College of Science University of Texas El Paso Department of Biological Science Ctr. for Environ. Rsrc. Management

In 1995 the National science Foundation (NSF) funded six minority-serving institutions in an effort to develop models for undergraduate science, technology, engineering, and mathematics (STEM) education that would increase the persistence, graduation, and success of all undergraduate STEM students;improve the quality of undergraduate STEM programs;and increase the diversity in STEM professions and graduate programs. The University of Texas at El Paso (UTEP), one of the six funded institutions, is located in the southwest corner of Texas bordering Juarez, Mexico and New Mexico. It primarily serves the predominantly Hispanic population of the region. Developed for all entering students in the College of science and College of engineering, the Circles of Learning for Entering Students (CircLES) program is a comprehensive institutional effort starting with a weeklong STEM summer orientation. CircLES also provides students with discipline-specific student advising and requires students to participate in one to two semesters of science or engineering-oriented learning communities, based on their pre-college preparation in Mathematics and English. This paper describes the design and findings of a five-year longitudinal study of student persistence in STEM since implementation of the program. Findings from the study indicate that students who participate in the program have higher retention rates in STEM, as well as at the University, and increased persistence toward graduation when compared to 1997 baseline rates. Similar results are observed when findings are disaggregated by gender, ethnicity, and level of entering mathematics course.

关键词： engineering education

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An Application of Semiconductor Sensors to Real Time, In-Situ Rain Gauges

An Application of Semiconductor Sensors to Real Time, In-Sit...

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Hydraulic Measurements and Experimental Methods 2002

作者： Lee, Sangsuk Schwartz, Franklin W. Kim, Jun Young Moon, Jong H. Environ. Science Graduate Program Ohio State University Department of Mechanical Engineering University of Illinois Urbana-Champaign Dept. of Mat. Sci. and Engineering Chonnam National University Kwangju Korea Republic of 223 Mendenhall Laboratory 125 S. Oval Mall Columbus OH 43210

ISBN: (纸本)0784406553

This paper presents results in an effort to develop an improved semiconductor rain gauge. A key feature of the rain gauge described herein is the use of piezoelectric ceramic elements to produce real time and direct signals. Another feature of the device is the ability to use the piezoelectric elements as sensors. A methodology is presented for analyzing the feasibility of using a semiconductor device as a key component of the rain gauge. A piezoelectric semiconductor, lead zirconate titanate (PZT) ceramic device, was investigated for the potential application. PZT discs were prepared through a modified sintering method to provide the optimal thickness and diameter for the device, which are key factors in controlling the resonance frequency. The microstructure of the device was determined by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The device was examined for its optimal resonance frequency using a laser scanning vibrometer in the time domain. The voltages induced by water drops were measured at the optimal resonance frequency with a spectrum analyzer. The voltage fluctuated according to the size of the water drops. This result suggests the PZT device could function as an alternative to the current rain gauges. The experimental results also indicate that even a single rain drop could be measured in real time using the PZT device. Separation of overlapping signals induced by rain drops falling within the relaxation time (10 ms) of the device is a problem that we are now examining, along with practical issues of the remote use of the device with a data logger.

关键词： Semiconductor devices

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Bioavailability of heavy metals in sewage sludge-amended Thai soils

Bioavailability of heavy metals in sewage sludge-amended Tha...

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The 1998 International Conference

作者： Parkpain, P. Sreesai, S. Delaune, R.D. Environmental Engineering Program Sch. of Environ. Rsrc. and Devmt. Asian Institute of Technology P.O. Box 4 Klongluang Pathumthani 12120 Thailand Environ. Health Science Department Faculty of Public Health Mahidol University Rajavithi Rd. Bangkok 10400 Thailand Wetland Biogeochemistry Institute Louisiana State University Baton Rouge LA 70803 United States

Plough and subsoil layers of two major agricultural soil series, Rangsit and Thonburi, found in Bangkok area of Thailand were studied for determining the bioavailability and solubility behavior of heavy metals (Cd, Cu, Zn, Mn, and Fe) following application of sewage sludge from a wastewater treatment plant and a series of laboratory experiments. The soils contained low indigenous heavy metals while the sludge contained higher amounts of heavy metals but in an acceptable range for application as plant nutrient source in agricultural soil. Applications of sewage sludge increased pH of the acid soil and available plant nutrients to the soils. The heavy metal concentration levels in the soils also increased. Most partitioned into easily mobile pools and later into sparingly mobile pools following 12 weeks of incubation time. Bioavailability forms of Cd in soil solution were low but that of Cu, Zn, and Mn remained elevated even at 12 weeks of the reaction time. Applied inorganic Zn depressed Cd sorption capacity of two soils studied but it had no effect on Cd desorption.

关键词： Heavy metals

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Measurements of trace metal (Fe, Cu, Mn, Cr) oxidation states in fog and stratus clouds

Measurements of trace metal (Fe, Cu, Mn, Cr) oxidation state...

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作者： Siefert, Ronald L. Johansen, Anne M. Hoffmann, Michael R. Pehkonen, Simo O. Environmental Engineering Science W.M. Keck Laboratories California Institute of Technology Pasadena CA United States Department of Civil Engineering University of Cincinnati Cincinnati OH United States Environ. Engineering Science Program Institute of Technology Pasadena CA United States

The oxidation state of Fe, Cu, Mn, and Cr in cloudwater was measured during several cloud events. The measurements were then used in thermodynamic-speciation models to understand the speciation of ambient fog and cloudwater. Cu and Mn were the predominant oxidation states during daylight and nighttime conditions increasing during daylight conditions. Mn concentrations were never high enough to influence the redox chemistry of Cr. Overall, Cr in cloudwater was predicted to be reduced to Cr(III) if free S(IV) is present.

关键词： Air pollution

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High-frequency near-bottom acoustic reflection signatures of hydrocarbon seeps on the Northern Gulf of Mexico continental slope

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Geo-Marine Letters 1998年第4期18卷 267-276页

作者： Sager, W.W. Lee, C.S. Macdonald, I.R. Schroeder, W.W. Department of Oceanography Texas A and M University College Station TX 77843 United States Geochem. and Environ. Research Group Texas A and M University College Station TX 77845 United States Marine Science Program University of Alabama Dauphin Island AL 36528 P.O. Box 369 United States Institute of Technology Samsung Engineering and Construction Seoul 135-080 Kangnam P.O. Box 1430 South Korea

Acoustic reflection signatures of four hydrocarbon seeps were classified using near-bottom 25-kHz echosounder profiles. Echo patterns were compared with ground-truth data obtained by submersible observations and shallow coring. Six echo types were distinguished: strong reflections from (1) exposed or (2) buried hard substrates, such as authigenic carbonate or gas hydrate;acoustic scattering in (3) unlayered or (4) layered sediments owing to gas, shells, or disseminated carbonates;(5) attenuation caused by gas;and (6) undisturbed sediments. Echo type distributions suggest that high spatial variability indicates a younger, vigorous seep, whereas extensive hard substrate implies an older, encrusted seep.

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