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Articles 361 - 390 of 14813

Full-Text Articles in Earth Sciences

Farm Workers And The Structural Basis Of Climate Change Perceptions, Cody Mortell, Anna Erwin, Zhao Ma, Dongkyu Kim, Elizabeth Rodriquez, Marla Perez-Lugo Jul 2026

Farm Workers And The Structural Basis Of Climate Change Perceptions, Cody Mortell, Anna Erwin, Zhao Ma, Dongkyu Kim, Elizabeth Rodriquez, Marla Perez-Lugo

School of Earth, Environmental, & Marine Sciences Faculty Publications

Farm workers are particularly vulnerable to climate change, especially from extreme heat; however, little is known about how they perceive this risk. This study examines climate change perceptions (CCP) among 404 farm workers surveyed in person in the Lower Rio Grande Valley, Texas from April to May 2024. Guided by Pierre Bourdieu’s theory of practice, we conducted a latent class analysis of economic, cultural, social, and symbolic capital indicators to identify distinct class profiles. We then assessed CCP by latent profile, using two primary outcome variables: (1) perceived temperature trends in the region (assessed alongside NOAA data) and (2) perceived …


An Emergent Seafood Nationalism Takes Hold In The United States, Owen Temby Jul 2026

An Emergent Seafood Nationalism Takes Hold In The United States, Owen Temby

School of Earth, Environmental, & Marine Sciences Faculty Publications

This paper introduces the concept of ‘seafood nationalism’ to describe how, since 2024–2025, the United States increasingly uses tariffs, trade remedies, food safety enforcement and origin-based rules to favour American seafood over foreign products. Federal actions include Executive Order 14276, Restoring American Seafood Competitiveness, which directs agencies to address unfair trade practices, unsafe imports and to develop a coordinated seafood trade strategy. Additional measures include a tariff package imposing a 10% duty on nearly all seafood imports and 30% on seafood from China, as well as new anti-dumping and countervailing duty orders on warm-water shrimp. This paper presents Gulf …


An Overlooked Terrestrial Archive: Freshwater Cements And Hydroclimate Signals In Quaternary Glaciogenic Deposits, Owen F. Mccaffrey, Ian Z. Winkelstern, Tara A. Kneeshaw, Melinda C. Higley Jun 2026

An Overlooked Terrestrial Archive: Freshwater Cements And Hydroclimate Signals In Quaternary Glaciogenic Deposits, Owen F. Mccaffrey, Ian Z. Winkelstern, Tara A. Kneeshaw, Melinda C. Higley

University Faculty Publications and Creative Works

Quaternary glaciogenic deposits, which serve as vital groundwater aquifers, are often partially cemented with carbonate minerals, but the timing of emplacement of these cements and their geochemical conditions of formation remain understudied. Here, we integrated petrography, δ18O, Mg/Ca, and clumped isotope (Δ47) data from two calcitecemented outcrops in western Michigan (USA) to investigate the origin of glacial sediment cements. The two sites have contrasting topographic and textural settings reflecting distinct formation conditions. The elevated Wabasis Lake deposit records sequential phreatic-to-vadose cementation, while the Cherry Valley Sands site, very close to the modern water table, shows a …


R Code And Supporting Data For "Fast And Slow Water Handling Strategies Explain Pinyon Pine Decline And Juniper Expansion", Andrew Kulmatiski, Muhammad Faraz Rehman Jun 2026

R Code And Supporting Data For "Fast And Slow Water Handling Strategies Explain Pinyon Pine Decline And Juniper Expansion", Andrew Kulmatiski, Muhammad Faraz Rehman

Browse all Datasets

This repository contains the datasets, R scripts, HYDRUS-1D model files, weather data, and supporting materials used for the M.S. thesis, "Fast and Slow Water Handling Strategies Explain Pinyon Pine Decline and Juniper Expansion." The study investigated root water uptake and water-use strategies of pinyon pine (Pinus edulis) and Utah juniper (Juniperus osteosperma) using stable isotope tracer experiments, soil water flow modeling, leaf water potential measurements, stomatal conductance measurements, and environmental data collected across an aridity gradient in southern Utah, USA.


Instructions To Authors, Academy Editors Jun 2026

Instructions To Authors, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Journal Acknowledgements And Editorial Board, Academy Editors Jun 2026

Journal Acknowledgements And Editorial Board, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Keynote Address And Meeting Program, Academy Editors Jun 2026

Keynote Address And Meeting Program, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Business Meeting Report (Secretary's And Treasurer's Report), Academy Editors Jun 2026

Business Meeting Report (Secretary's And Treasurer's Report), Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Sperm Morphology In The Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth Jun 2026

Sperm Morphology In The Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth

Journal of the Arkansas Academy of Science

Studies by Scheltinga et al. (2002) and Scheltinga and Jamieson (2003) provide the most comprehensive analysis and only review of sperm morphology in Narrow-Mouthed Frogs (family Microhylidae). Of the 490+ species known to occur in this anuran family (Vitt and Caldwell 2014), only 3 are distributed in the United States (Powell et al. 2016), and 2 of these occur in Arkansas (Trauth et al. 2004). Surprisingly, sperm studies on only 12 microhylid species have been conducted (Scheltinga and Jamieson 2003), and no sperm studies are available on any North American species.


Multiple Nuclear Configurations And Microtubular Arrangements In Spermatozoa Of The Western Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth Jun 2026

Multiple Nuclear Configurations And Microtubular Arrangements In Spermatozoa Of The Western Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth

Journal of the Arkansas Academy of Science

I examined the ultrastructure of spermatozoa of the Western Siren, Siren nettingi, using transmission electron microscopy. My primary objective in this study was to elucidate, for the first time, the unique morphological complexity of biflagellated sperm in this species. This study also represents my fifth addition in a series of investigations that highlight the novel nature of all aspects of spermatogenesis in this salamander I show the basic sperm transverse and sagittal design which includes a nucleus, 2 axial fibers supporting 2 undulating membranes which have 2 axonemes residing at their terminal ends, several circular mitochondria, and several electron-dense masses. …


Binucleation And Seasonal Cycle Of Sertoli Cells In The Western Lesser Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth Jun 2026

Binucleation And Seasonal Cycle Of Sertoli Cells In The Western Lesser Siren, Siren Nettingi (Caudata: Sirenidae), S. E. Trauth

Journal of the Arkansas Academy of Science

I examined binucleation and the seasonal cycle of Sertoli cells in the Western Siren (Siren nettingi) using light microscopy and transmission electron microscopy. My primary objective in this study was to report, for the first time, the presence of double nuclei in Sertoli cells in a salamander. This study also represents the sixth contribution in a series of investigations that highlight the novel nature of all aspects of spermatogenesis in this unique salamander. My findings add to a growing list of extraordinary morphological and reproductive features that distinguish this salamander from all other vertebrates.


Distal Urogenital Anatomy And Epithelial Morphology In The Male Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth Jun 2026

Distal Urogenital Anatomy And Epithelial Morphology In The Male Eastern Narrow-Mouthed Frog, Gastrophryne Carolinensis (Anura: Microhylidae), S. E. Trauth

Journal of the Arkansas Academy of Science

I investigated the microanatomy of the distal urogenital system in male Eastern Narrow-Mouthed Frogs (Gastrophryne carolinensis) from a small sample (n = 5) collected in central Arkansas in April, May, and July (2021) and May 2022. Specifically, my primary goals were to elucidate the histology of the following: (1) the paired Wolffian (urogenital) ducts caudally from the kidneys to their merging with the urodeum of the cloaca, (2) the structure of seminal vesicles, and (3) the epithelial morphologies among the distal urogenital tract, the posterior alimentary canal, and the cloaca. My histological analysis confirmed the presence of …


Academy Presidents And Institutional Members, Academy Editors Jun 2026

Academy Presidents And Institutional Members, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Table Of Contents, Academy Editors Jun 2026

Table Of Contents, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Journal Of The Arkansas Academy Of Science Volume 79, Academy Editors Jun 2026

Journal Of The Arkansas Academy Of Science Volume 79, Academy Editors

Journal of the Arkansas Academy of Science

No abstract provided.


Editorial: Plant Responses To Abiotic Stress: Unraveling Complex Mechanisms Through Genomics And Physiology, Mizanur Rahman, Takashi Asaeda, Md Harun Rashid Jun 2026

Editorial: Plant Responses To Abiotic Stress: Unraveling Complex Mechanisms Through Genomics And Physiology, Mizanur Rahman, Takashi Asaeda, Md Harun Rashid

School of Earth, Environmental, & Marine Sciences Faculty Publications

No abstract provided.


Impact On Energy Budgets In Grassland Production And Conservation Of Possible Production Of Energy From Biomass Crops, R J. Wilkins Jun 2026

Impact On Energy Budgets In Grassland Production And Conservation Of Possible Production Of Energy From Biomass Crops, R J. Wilkins

IGC Proceedings (1977-2023)

There is commonly a conflict between output/unit of area of land and output/unit of support-energy (SE) input. The possibil­ity of using a proportion of the total land area for biomass energy production suggests an approach for calculating grassland out­put/ha unconfounded with differences in SE input. Output can be calculated for an area of land that is devoted to grassland and biomass energy crops in proportions that result in a net demand for SE of zero. Outputs of utilized metabolizable energy (UME) are related to inputs of SE for (1) grazed grass with high application of nitrogen (N) fertilizer and (2) …


Efficiency Of Dairying Under Contrasting Feeding And Management Systems In North America, Israel, Europe, And New Zealand, J.D. J. Scott Jun 2026

Efficiency Of Dairying Under Contrasting Feeding And Management Systems In North America, Israel, Europe, And New Zealand, J.D. J. Scott

IGC Proceedings (1977-2023)

Four different systems of feeding and managing dairy cattle are seen in major milk-producing countries. These are (1) feeding purchased roughages and concentrates to zero-grazed, intensively penned cows; (2) home growing of roughages and most con­centrates for zero-grazed animals; (3) feeding concentrates with conserved pasture and other roughages in winter and reduced concentrates to grazed cattle in spring-summer; and (4) feeding cattle on grazed pasture and conserved pasture throughout the year. The following data on the four systems were obtained from examples in southern California, Wisconsin, England/Wales, and New Zealand. Average fat-corrected milk (FCM)/cow is approximately 7,140, 5,300, 4,670, and …


Potential Contribution Of White Clover To The Economics And Support-Energy Inputs Of Grass-Based Beef-Production Systems, T A. Stewart, R E. Haycock, A S. Laidlaw Jun 2026

Potential Contribution Of White Clover To The Economics And Support-Energy Inputs Of Grass-Based Beef-Production Systems, T A. Stewart, R E. Haycock, A S. Laidlaw

IGC Proceedings (1977-2023)

Biological output, gross margins, and efficiency of support-energy usage in an 18-month beef-production system on grass-white clover swards receiving either 50 kg N/ha stocked at 3.3 head/ha (low N) or 300 kg N/ha stocked 4.5 head/ha (high N) were compared. To date, two production cycles (1977-1979 and 1978-1980) at two sites have been completed. Mean live-weight and carcass gains/ha were, respectively, 17.5% and 14% higher from the high-N than from the low-N system. Gross margin/head was higher from the high-N system in the first production cycle but not in the second. In the low-N system as com· pared with the …


An Evaluation Of The Black Walnut- Tall Fescue Pasture-Management System, H E. Garrett, W B. Kurtz Jun 2026

An Evaluation Of The Black Walnut- Tall Fescue Pasture-Management System, H E. Garrett, W B. Kurtz

IGC Proceedings (1977-2023)

The economic and biological feasibility. of a black walnut-livestock-grazing multicropping-management regime bas been evaluated for comparison with a similar livestock-management regime conducted in the open. Pure tall fescue plots were established under open and black walnut-shade conditions. Forage yields on a dry-weight basis were estimated for a 3-year period. A concurrent grazing trial was co􀀌ducted on similar sites using 1.2-ha plots. Black walnut seedlings were planted within the plots on a 3 x 12-m spacing and protected from grazing animals by electric fencing. The economic analyses of the alternate grazing systems were based on their respective present net worth and …


Economics Of Renovating Mountain Hay Meadows, J J. Jacobs Jun 2026

Economics Of Renovating Mountain Hay Meadows, J J. Jacobs

IGC Proceedings (1977-2023)

There are approximately 0.5 million hectares (ha) of irrigated native grass hay in the mountain and intermountain regions of California, Oregon, Idaho, Utah, Nevada, Montana, Wyoming, and Colorado. Often these lands are not producing at their full physical or economic potential. The objectives of this study were to identify alternative improvement procedures to increase hay production and to determine the economic feasibility of those alternatives. The principal means of identifying alternative mountain hay-meadow improvement practices and their costs was personal in­terviews with ranchers. The ranchers interviewed were owners and/or operators of mountain ranches in Wyoming who were us­ing or had …


Pasture Demonstration Program For Beef: Economic Considerations, P R. Hasbargen, R H. Craven, N P. Martin Jun 2026

Pasture Demonstration Program For Beef: Economic Considerations, P R. Hasbargen, R H. Craven, N P. Martin

IGC Proceedings (1977-2023)

This study made an economic evaluation of several alternative pasture improvement programs on beef farms in northern Minnesota. Three questions were addressed relative to several pasture improvement systems. These were (1) Will it pay? (2) Is there a cheaper way? and (3) Is there a more profitable system for a particular farm resource situation? Partial budgeting and computerized linear programming techniques were used to analyze pasture cost and return data obtained from several ranches in northern Minnesota. Study results show that rented pastures, when available, provided the cheapest source of additional summer feed, and that legume pastures provide cheaper sources …


Pennsylvania's Alfalfa Growers Program: Four Years Of Success, J E. Baylor, L E. Lanyon, W K. Waters Jun 2026

Pennsylvania's Alfalfa Growers Program: Four Years Of Success, J E. Baylor, L E. Lanyon, W K. Waters

IGC Proceedings (1977-2023)

Alfalfa (Medicago sativa L.) is the most important perennial forage legume grown in Pennsylvania. However, yields currently reported by farmers are considerably below what might be expected when all production inputs are utilized. Therefore, a pro­gram was developed (1) to measure how much alfalfa hay, protein, and energy can be pro􀀗uced on 1 ha of Pennsylvania land under nonirrigated conditions, (2) to determine the mineral content and uptake by high-yielding alfalfa crops, and (3) to obtain more realistic on-farm estimates of alfalfa production costs. To achieve the program goals, hay production for each harvest from 2.02-ha farm fields was …


Estimation Of Digestibility Of Legume Forages By Means Of Morphological Parameters, W Kuhbauch Jun 2026

Estimation Of Digestibility Of Legume Forages By Means Of Morphological Parameters, W Kuhbauch

IGC Proceedings (1977-2023)

Forage quality is normally evaluated by time-consuming and costly laboratory analyses. It appears promising to use mor­phological parameters to evaluate forage quality in alfalfa and red clover. During progressive growth of white clover, red clover, and alfalfa, the leaf and stem portion was separated to determine the fiber fraction according to the Van Soest method and to

estimate digestibility by the procedure of Tilley and Terry. Stem : leaf ratio and stand height as a measure of stem length were used as morphological parameters. Leaves of the three legumes vary only slightly in concentration of cell-wall material and in digestibility …


Income, Costs, And Profits Associated With Feeding Selected Forages To Dairy Cows, D D. Dornfeld, D A. Rohweder, W T. Howard Jun 2026

Income, Costs, And Profits Associated With Feeding Selected Forages To Dairy Cows, D D. Dornfeld, D A. Rohweder, W T. Howard

IGC Proceedings (1977-2023)

Over the last i0 years, dairy-farm enterprises have g:ro-wn in size, with an apparent increase in use of improved scientific feeding and management techniques. There in growing emphasis on automated feeding and milking and on management stcategies in an attempt to reduce labor needs and allow more cows/worker. The average herd size in the sample population was 76.8 cows. There was difficulty finding herds over 100 and under 40 head. It appears that the trend toward increasing growth will continue, as much as sufficient capital, management ability, and debt service capacity eJi:ist to permit the growth to occur. Forage management …


Economic Analysis Of The Impact Of Management Decisions On Production And Use Of Silage For A Dairy Enterprise, A J. Corrall, H D. St. C Neal, I M. Wilkinson Jun 2026

Economic Analysis Of The Impact Of Management Decisions On Production And Use Of Silage For A Dairy Enterprise, A J. Corrall, H D. St. C Neal, I M. Wilkinson

IGC Proceedings (1977-2023)

The aim of this work was to examine the influence of variations in grass management and methods of ensiling on the economics of milk production for autumn-calving cows. A simulation model was developed to combine knowledge of plant and animal responses and their interactions in order to calculate the effects of management options on economic balances. Input data were compiled for herbage production from cut­ting strategies that gave herbage at four digestibilities, at two levels of applied nitrogen, and in three climates. Experimental evidence was also collated to construct matrices of loss of dry matter and changes in digestibility and …


Role And Effectiveness Of U.S. Universities In Training Professionals For Work In International Agriculture, D F. Fienup Jun 2026

Role And Effectiveness Of U.S. Universities In Training Professionals For Work In International Agriculture, D F. Fienup

IGC Proceedings (1977-2023)

Problems of hunger, malnutrition, and world food security became a major world concern in the 1970s. Two U.S. presiden­tial reports have emphasized the seriousness of the situation and the need to expand food production and distribution, par­ticularly in the less-developed countries (LDCs) where hunger is most severe. The LDCs need to strengthen agricultural teaching, research, and extension in order to develop and disseminate the ap­propriate technology farmers need to increase food production. The most limiting factor is often the lack of trained scientists to provide local leadership and expertise. Here U.S. and other developed-country universities are needed to train LDC …


Innovations In Academic Curricula For International Education, D D. Dwyer Jun 2026

Innovations In Academic Curricula For International Education, D D. Dwyer

IGC Proceedings (1977-2023)

A major contribution of U.S. AID to developing countries has been to support the education of host-country nationals. This form of assistance has not been without its problems, as both AID and the universities themselves have been less than totally ef­fective in meeting the challenge of providing an education that best serves the student and the home country. In most developing countries, the B.S. degree serves as an adequate scientific foundation for staffing agricultural programs. This is not to argue against higher levels of education but to state that faster progress could be made by spreading the educational efforts among …


Effective Training For International Students, G W. Thomas Jun 2026

Effective Training For International Students, G W. Thomas

IGC Proceedings (1977-2023)

The observations made in this paper are based upon contacts with international students, both in the U.S. and in many other countries. Two of the most serious problems in increasing world food production in the developing world are (1) lack of trained people, and (2) technology transfer. A third constraint, inadequate research, is also critical but not of the magnitude of the other two, since there is a great amount of research information available that is not being adequately ut:ilized. Training needs fall into two general categories in which deficiencies are obvious: (1) graduate-level programs, particularly in the applied fields …


West Virginia University Allegheny Highlands Project: A Ten-Year Experiment In Technology Transfer, B S. Baker, P E. Lewis, E K. Inskeep, R H. Maxwell Jun 2026

West Virginia University Allegheny Highlands Project: A Ten-Year Experiment In Technology Transfer, B S. Baker, P E. Lewis, E K. Inskeep, R H. Maxwell

IGC Proceedings (1977-2023)

West Virginia's livestock industry is characterized by relatively small units located predominantly on rough terrain not suited to highly mechanized or intensive agriculture. As a result of changes in West Virginia agriculture during the last 40 years, there has been a reduction in support from agribusiness, marketing alternatives, and profitability. Some agriculturalists contend that if present technology were adopted, beef and sheep farms in mountainous regions could be profitable and could contribute to the local economy. The objective of the Allegheny Highlands Project (AHP) was to test the effectiveness of a method for delivering technological information to farmers to promote …