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Articles 30781 - 30810 of 294415

Full-Text Articles in Physical Sciences and Mathematics

The Basel Problem And Summing Rational Functions Over Integers, Pranjal Jain Mar 2024

The Basel Problem And Summing Rational Functions Over Integers, Pranjal Jain

Rose-Hulman Undergraduate Mathematics Journal

We provide a general method to evaluate convergent sums of the form ∑_{k∈Z} R(k) where R is a rational function with complex coefficients. The method is entirely elementary and does not require any calculus beyond some standard limits and convergence criteria. It is inspired by a geometric solution to the famous Basel Problem given by Wästlund (2010), so we begin by demonstrating the method on the Basel Problem to serve as a pilot application. We conclude by applying our ideas to prove Euler’s factorisation for sin x which he originally used to solve the Basel Problem.

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Silvopastoral Agroforestry In Upland And Lowland Uk Grassland: Tree Growth And Animal Performance, W R. Eason, R Lavender, R O. Clements, C Duller, E Gill, M Hislop Mar 2024

Silvopastoral Agroforestry In Upland And Lowland Uk Grassland: Tree Growth And Animal Performance, W R. Eason, R Lavender, R O. Clements, C Duller, E Gill, M Hislop

IGC Proceedings (1977-2023)

Trees, individually protected from herbivore damage using plastic shelters, were planted at two densities (100 and 400 stems/ha) into sheepgrazed pasture in upland and lowland UK grassland sites in 1988. Tree and animal performance were compared with conventional forestry (no sheep) and pasture (no tree) systems. Effects on tree growth and survival are highly species and site dependent although some treatment effects did emerge. Tree shelters encouraged rapid early height growth compared to forestry controls although in some cases tree form was also adversely affected. Generally tree performance within agroforestry treatments was better at the higher planting density. Eight years …

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Use Of Annual Self-Reseeding Legumes In An Oak Forest In Central Italy, P Talamucci, G Argenti, A Pardini, S Piemontese, N Stagliano Mar 2024

Use Of Annual Self-Reseeding Legumes In An Oak Forest In Central Italy, P Talamucci, G Argenti, A Pardini, S Piemontese, N Stagliano

IGC Proceedings (1977-2023)

A trial has been carried out for three years in an oak coppice geometrically thinned out of Mediterranean Central Italy, about the functioning of a pastoral system made by four different resources: native pasture, subterranean clover (Trifolium brachycalycinum Katzn. et Morley) in pure stand, strips thinned out and firebreaks improved with oversown subclover, all grazed by sheep. Subclover increased the forage yield and improved the palatabilty of the pasture and the regularity of grazing; the higher biomass intake by animals reduced the quantity of dried biomass in summer and contributed to keep low either fire hazards or flame diffusion …

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The Effects Of Shelterbelts On Adjacent Pastures And Soils In A Temperate Climate, A G. Gillingham, M F. Hawke Mar 2024

The Effects Of Shelterbelts On Adjacent Pastures And Soils In A Temperate Climate, A G. Gillingham, M F. Hawke

IGC Proceedings (1977-2023)

Two trials were conducted to differentiate the direct (exposure) from the indirect (modified soil fertility due to nutrient transfer by grazing animals) effects of farm shelterbelts on associated pasture growth.Soil from close to “unmanaged”shelterbelts with dense shelter to ground level had relatively high potassium (K) levels and, in a glasshouse situation, provided more pasture growth than soil from further distances, or from adjacent to “managed” shelterbelts. Pasture grown in boxes of a common soil implanted at increasing distances from a shelterbelt also produced highest growth rates close to shelter. These results generally explain the pattern of resident pasture growth, except …

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Temperate Pasture And Sheep Performance Under Radiata Pine And In Open Pasture, K M. Pollock, R J. Lucas, D B. Pownall, S E. Thomson Mar 2024

Temperate Pasture And Sheep Performance Under Radiata Pine And In Open Pasture, K M. Pollock, R J. Lucas, D B. Pownall, S E. Thomson

IGC Proceedings (1977-2023)

Forage production from years 4 to 6 of an agroforestry system at 400-600 trees per ha and pasture alone were compared for a temperate sub-humid environment. Forage production was best for lucerne pasture followed by phalaris/clover and cocksfoot/clover, and least for ryegrass/clover and the ryegrass only pastures. Total pasture production in the agroforest relative to the open pasture was from 10% more for phalaris to 20% less for lucerne. Sheep carrying capacity over all pastures was 14.6 sheep/ha in the open and 11.8 sheep/ha in the agroforest and varied by ±15% according to the pasture types.

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Grazing Management Of Tagasaste (Chamaecytisus Proliferus) For Sheep And Cattle Production In Southern Australia, N J. Edwards, G M. Allen, D M. Mcneill, C M. Oldham Mar 2024

Grazing Management Of Tagasaste (Chamaecytisus Proliferus) For Sheep And Cattle Production In Southern Australia, N J. Edwards, G M. Allen, D M. Mcneill, C M. Oldham

IGC Proceedings (1977-2023)

Direct grazing of hedgerows of tagasaste (Chamaecytisus proliferus) by sheep or cattle appear to be very robust systems. Tagasaste persists under a continuous grazing regime with cattle such that plant regrowth maintained between 5 and 10 cm in length produces in excess of 215 kg of animal liveweight/ha/year. This level of production is also sustained within a rotational grazing regime. Under both grazing systems cattle production within a year is highly seasonal, with liveweight gains from young cattle peaking at 1.0-1.5 kg/head/day in winter and spring, but dropping to maintenance only by late summer-autumn. Sheep, like cattle, can …

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Shrub Palatability To Rusa Deer (Cervus Timorensis Russa) In New Caledonia, C Corniaux, S Le Bel, J M. Sarrailh Mar 2024

Shrub Palatability To Rusa Deer (Cervus Timorensis Russa) In New Caledonia, C Corniaux, S Le Bel, J M. Sarrailh

IGC Proceedings (1977-2023)

The objective of this study was to determine a palatability scale of five shrub legumes to rusa deer during the dry season in New Caledonia. Acacia ampliceps and Samanea saman remain low in acceptability. Gliricidia sepium is more palatable but quite less than Leucaena leucocephala (native cultivar) and Calliandra calothyrsus (San Ramon). Therefore, since the regression of Leucaena leucocephala population, Calliandra calothyrsus could be very promising to replace it in the deer diet. On the other hand, Acacia ampliceps seems to be the most interesting shrub legume to plant in the west coast, where soil erosion, due to successive droughts …

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Soil Nutrient Redistribution Pattern About The Tree In A Silvopastoral System, L C. Nwaigbo, H G. Miller, A R. Sibbald, G Hudson Mar 2024

Soil Nutrient Redistribution Pattern About The Tree In A Silvopastoral System, L C. Nwaigbo, H G. Miller, A R. Sibbald, G Hudson

IGC Proceedings (1977-2023)

The objective of this paper is to report the effect of animal-tree interactions on soil nutrient redistribution pattern in a grazed silvopastoral experiment site at Glensaugh, in NE Scotland. Scots pine (Pinus sylvestris L) tree species were planted in square lattice arrangements at 5 m x 5 m, spacing (400 stems/ha) on plots replicated over three blocks in Randomized Complete Block design on a predominantly rye grass (Lolium perenne L) pasture which was grazed by sheep yearly from April to October. Included in the design were grazed pasture plots without trees (Control). Soil samples were collected from around …

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Trees For Shelter: The Implications In Agroforestry System, L C. Nwaigbo, A R. Sibbald, G Hudson Mar 2024

Trees For Shelter: The Implications In Agroforestry System, L C. Nwaigbo, A R. Sibbald, G Hudson

IGC Proceedings (1977-2023)

The objective of this study was to determine the horizontal and vertical variations in soil penetration resistance (PR) observed at tree-scale in silvopastoral plots that were grazed by sheep with and without trees. Sycamore trees (Acer pseudoplatanus L) were planted in the spring of 1988 at 10 m x 10 m spacing (100 stems/ha) at Glensaugh NE of Scotland on plots replicated over three blocks in Randomized Complete Block design on a predominantly rye grass (Lolium perenne L) pasture. Included in the design were pasture plots without trees (Control). The experiment is grazed by sheep yearly from April to …

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A Silvopastoral System In The North Atlantic Zone Of Costa Rica: Combining Indigenous Timber Species With Dairy Pasture Swards, A Moulaert- Quiros, J P. Mueller, M Villarreal, R Piedra, L Villalobos Mar 2024

A Silvopastoral System In The North Atlantic Zone Of Costa Rica: Combining Indigenous Timber Species With Dairy Pasture Swards, A Moulaert- Quiros, J P. Mueller, M Villarreal, R Piedra, L Villalobos

IGC Proceedings (1977-2023)

The objective of this study was to design, establish and monitor a silvo pastoral experiment on a dairy farm in the northern Atlantic region of Costa Rica. Indigenous timber species, Vochysia guatemalensis and Hyeronima alchorneoides were used together with or without the tropical pasture legume, Arachis pintoi in a split plot design with a 4 x 2 x 2 factorial arrangement. First year establishment was good for the tree component (2.3 to 10 % mortality) but poor for A. pintoi (4 to 5 % of sward). Poor legume establishment was attributed to lax grazing management and excess competition from existing …

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Productivity Of Three Tree Legumes Grazed By Cattle, R C. Gutterridge Mar 2024

Productivity Of Three Tree Legumes Grazed By Cattle, R C. Gutterridge

IGC Proceedings (1977-2023)

Three tree legumes Albizia chinensis, Leucaena leucocephala K 636 and Tipuana tipu were grown in conjunction with the grass Brachiaria decumbens and grazed by weaner cattle at a stocking rate of 2.5 animals per hectare for a total of 447 days. Albizia was best adapted to this acidic, poorly drained site in south east Queensland giving the highest yields of edible dry matter, high survival rate and moderate liveweight gains of 0.45 kg/head/day. The productivity of L. leucocephala K 636 was always poor but it gave the highest liveweight gains of all treatments in the first 280 days of grazing, …

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Morphological And Physiological Response Of Planeleaf Willow (Salix Planifolia Pursh.) To Simulated Browsing, L Xu, J L. Dodd, M A. Smith, Q D. Skinner, W A. Laycock Mar 2024

Morphological And Physiological Response Of Planeleaf Willow (Salix Planifolia Pursh.) To Simulated Browsing, L Xu, J L. Dodd, M A. Smith, Q D. Skinner, W A. Laycock

IGC Proceedings (1977-2023)

Morphological and physiological responses of planeleaf willow (Salix planefolia Pursh.) to simulated browsing were studied under controlled conditions. The treatments consisted of every combination of three clipping intensities (30%, 60% and 90% of current twigs length removal) and three clipping timings (late winter, early spring and mid-summer). Increased clipping intensity stimulated bud activation; increased total leaf area and leaf size and increased the length of current year’s twigs. Mid-summer browsing increased the total number of leaves, the number of current twigs and decreased the length of current twigs. Higher browsing intensity resulted in higher photosynthetic rate of recently matured …

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Psyllid Resistance In The Leucaena Genus, B F. Mullen, H M. Shelton, F Gabunada, W W. Stur Mar 2024

Psyllid Resistance In The Leucaena Genus, B F. Mullen, H M. Shelton, F Gabunada, W W. Stur

IGC Proceedings (1977-2023)

Leucaena species varied from highly susceptible to highly resistant in their response to the psyllid insect (Heteropsylla cubana) at 2 sites, a high psyllid environment at Brisbane, Australia and a moderate psyllid environment at Los Baños, Philippines. L. leucocephala was the most susceptible species. There was considerable intraspecific variation in psyllid resistance within L. collinsii, L. diversifolia and L. pallida. Plant reponse to psyllid challenge between environments was highly correlated but not linear. The higher psyllid challenge environment at Brisbane permitted greater discrimination between species and fewer Leucaena species were ranked as psyllid resistant.

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Fodder Production Of Multipurpose Trees In A Maize Farming System Of Subhumid Southern Africa, B H. Dzowela, L Hove, P L. Mafongoya Mar 2024

Fodder Production Of Multipurpose Trees In A Maize Farming System Of Subhumid Southern Africa, B H. Dzowela, L Hove, P L. Mafongoya

IGC Proceedings (1977-2023)

Ways to integrate fodder production into maize production systems under Southern Africa’s subhumid conditions have been studied. One way involves the planting of tree and grass fodder hedges along soil conservation contour-bunds in maize fields. Management factors that influence the productivity of maize and fodder components in the system are fodder spp., side-pruning and deferment of wet season cutting. The other option involves interplanting tree fodders with maize through the use of a coppicing tree such as Acacia angustissima. Practical applications of these methods in mixed crop-livestock production systems are discussed.

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Differences In Chemical Composition Among Provenances Of Browse Species In A Subhumid Environment: Relation To Use As Supplements, B H. Dzowela, L Hove, P L. Mafongoya Mar 2024

Differences In Chemical Composition Among Provenances Of Browse Species In A Subhumid Environment: Relation To Use As Supplements, B H. Dzowela, L Hove, P L. Mafongoya

IGC Proceedings (1977-2023)

Studies were initiated in a subhumid Southern African environment to assess the chemical composition and nutritive value of Acacia angustissima (Mill.) Kuntze, Calliandra calothyrsus Meiss. and Leucaena species. The objective was to determine variability in crude protein (CP) concentration, acid detergent fibre (ADF), neutral detergent fibre (NDF), and soluble and insoluble proanthocyanidins from fodder samples of species, subspecies and provenances. A wide range was found in these parameters. The implications of these chemical composition factors, especially proanthocyanidins, on the use of these browse fodders in livestock feeding systems are discussed.

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Tree Forages As Nitrogen Source For Ruminants In Sahelian Agro-Silvipastoral Systems, S T. Fall, B M. Doreau Mar 2024

Tree Forages As Nitrogen Source For Ruminants In Sahelian Agro-Silvipastoral Systems, S T. Fall, B M. Doreau

IGC Proceedings (1977-2023)

Tree forages contribute up to 80% DM and 100% nitrogen content in the ruminants diet in the Sahel during the dry season. However, crude protein (CP) concentration in browse within a wide range and variation factors remain to be elucidated for better integration of browses in ruminants feeding systems. Variation factors of CP content and in vivo digestibility of four Sahelian browse species were investigated to appreciate the potential as nitrogen sources in Sahelian ruminant feeding systems. Seasonal variations in nitrogen content were evaluated in different plants part of A. raddiana, B. rufescens, B. aegyptiaca and G. senegalensis harvested in …

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Introduction Of Multipurpose Tree Species For Improving The Productivity Of Grasslands In The Tropics, N G. Hegde, C Sall, T Nolan, J Connolly Mar 2024

Introduction Of Multipurpose Tree Species For Improving The Productivity Of Grasslands In The Tropics, N G. Hegde, C Sall, T Nolan, J Connolly

IGC Proceedings (1977-2023)

To improve the productivity of the Sahelian pastures, 10 different tree species were introduced and cattle, sheep and goats were allowed to graze. After a year of establishment, survival rate of different species ranged from 6% to 68%. Acacia senegal, Acacia seyal, Acacia nilotica, Combretum aculeata and Prosopis cineraria performed well and the impact of browsing by goats was severe.

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Evaluation Of Animal Productivity In A Sustainable Grazing System Based On The Use Of Trees In Association With Pastures, J M. Iglesias Gomez Mar 2024

Evaluation Of Animal Productivity In A Sustainable Grazing System Based On The Use Of Trees In Association With Pastures, J M. Iglesias Gomez

IGC Proceedings (1977-2023)

Young bulls of different breeds ( Zebu, Holstein and F-1 strain Holstein Zebu) were grazing together on a meadow composed of Guinea grass (Panicum maximum), Brachiaria (Brachiaria decumbens) and a mixture of natural pastures, all in association with Leucaena (Leucaena leucocephala) sown at a density of 555 plants per ha in order to evaluate the potential of that system for beef production. A completely randomized design was used. The meadow was rotationally grazed at stocking rate of 3.6 animal per ha. During the 18 months of fattening the best results were obtained with the Zebu type. …

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Changes In Understorey Pasture Composition In Agroforestry Regimes In New Zealand, M F. Hawke, A G. Gillingham Mar 2024

Changes In Understorey Pasture Composition In Agroforestry Regimes In New Zealand, M F. Hawke, A G. Gillingham

IGC Proceedings (1977-2023)

Long term Agroforestry trials were established in the North and South Islands of New Zealand between 1971-76. They compared a range of final tree stockings of Pinus radiata planted into pasture with open pasture control plots and were measured for tree growth parameters and agricultural production. This paper presents the results of pasture species changes over the period of tree age 10-22 years. Pasture species composition under Pinus radiata changed with time, dependent primarily on the rate of canopy closure. Changes occurred relatively rapidly in high tree stocked areas of 400 stems per hectare (sph) in the North Island trials …

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Forestry, A Valuable Crop For The Pastoral Farmer, N M. Shadbolt Mar 2024

Forestry, A Valuable Crop For The Pastoral Farmer, N M. Shadbolt

IGC Proceedings (1977-2023)

The integration of forestry into a pastoral system (sheep & beef cattle) will be discussed with respect to the economic sustainability of the system. The cash flow implications for a case study farm of forest development, and methods used through forestry right agreements to facilitate these by reducing risk, will be developed.

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The Effects Of Tree Density On Pasture Production Under Acacia Melanoxylon, B S. Thorrold, I L. Power, M B. Dodd Mar 2024

The Effects Of Tree Density On Pasture Production Under Acacia Melanoxylon, B S. Thorrold, I L. Power, M B. Dodd

IGC Proceedings (1977-2023)

Silvi-pastoral systems could contribute to greater total productivity and more sustainable land management of grazed pastures in New Zealand. Despite this potential, little is known of the interactions of tree species and environment on pasture growth. In this paper we report the effects of tree density on pasture yield in an Acacia melanoxylon silvi-pastoral system. The results show decreasing pasture yield with increasing tree density, although the extent of the reduction is less than would be expected under Pinus radiata. Results suggest that shade is the dominant factor causing yield decline in this study, while reduced N availability is …

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Long-Term Impact Of Leucaena-Based Grazing Systems On Soil Acidity, A D. Noble, R J. Jones Mar 2024

Long-Term Impact Of Leucaena-Based Grazing Systems On Soil Acidity, A D. Noble, R J. Jones

IGC Proceedings (1977-2023)

Soil acidification and land degradation issues are assuming increasing importance in Australia and challenging the concept of sustainablity of current land management systems. In this study the impact of a 22 year old Leucaena leucocephala / Urochloa mosambicensis (Leucaena) pasture production system on soil acidification and selected soil chemical properties was compared to an adjacent Urochloa mosambicensis (Sabi) area. Significant acidification and cation depletion was observed to 70 cm under the Leucaena when compared to the Sabi system. The net acidification rate for the Leucaena system was estimated to be 2.73 kmol H+ ha-1 yr-1 of which 0.17 kmol …

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Farmers' Screening Of Indigenous Fodder Trees And Shrubs In Kenya, R L. Roothaert, H K. Arimi, E N. Kamau Mar 2024

Farmers' Screening Of Indigenous Fodder Trees And Shrubs In Kenya, R L. Roothaert, H K. Arimi, E N. Kamau

IGC Proceedings (1977-2023)

The lack of fodder quantity and quality is a constraint for small scale livestock production systems in central Kenya which are intensive or are rapidly becoming so. This study examined farmers’ knowledge about indigenous fodder trees and shrubs (IFTS) which are fed to livestock. The study consisted of a formal survey in three agroecological zones with mean annual rainfall varying from 750 to 1400 mm. Farmers rated IFTS for different qualities, which were analysed by Chi square. Differences of ratings among species for these qualities were significant (p<0.05). The most promising species for the sub-humid zone, in terms of what farmers want to plant and in terms of preliminary nutritive analysis, were: Tithonia diversifolia, Commiphora zimmermanii, Ficus spp. and Trema orientalis. The species …

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Considerations For The Use Of Porcine Organ Donation Models In Preclinical Organ Donor Intervention Research, Frazer I. Heinis, Shaheed Merani, Nicholas W. Markin, Kim F. Duncan, Michael J. Moulton, Lance Fristoe, William E. Thorell, Raechel A. Sherrick, Tami R. Wells, Matthew T. Andrews, Marian Urban Mar 2024

Considerations For The Use Of Porcine Organ Donation Models In Preclinical Organ Donor Intervention Research, Frazer I. Heinis, Shaheed Merani, Nicholas W. Markin, Kim F. Duncan, Michael J. Moulton, Lance Fristoe, William E. Thorell, Raechel A. Sherrick, Tami R. Wells, Matthew T. Andrews, Marian Urban

School of Natural Resources: Faculty Publications

Use of animal models in preclinical transplant research is essential to the optimization of human allografts for clinical transplantation. Animal models of organ donation and preservation help to advance and improve technical elements of solid organ recovery and facilitate research of ischemia–reperfusion injury, organ preservation strategies, and future donor-based interventions. Important considerations include cost, public opinion regarding the conduct of animal research, translational value, and relevance of the animal model for clinical practice. We present an overview of two porcine models of organ donation: donation following brain death (DBD) and donation following circulatory death (DCD). The cardiovascular anatomy and physiology …

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Unraveling Biases And Customer Heterogeneity In E-Commerce Recommendation Systems, Sachin Sharma Mar 2024

Unraveling Biases And Customer Heterogeneity In E-Commerce Recommendation Systems, Sachin Sharma

Dissertations

This research explores the biases present in AI algorithms within e-commerce recommendation systems, focusing on how these biases prioritize popular, sponsored, and private-label products over actual customer preferences. We extend the responsible AI discourse by critically examining these biases and their implications for fairness in e-commerce. To strengthen the current understanding of AI fairness in the fields of information systems and computer science, we aim to challenge the assumption that AI fairness is objective and the same for everyone. We examine how individual differences, such as equity sensitivity and exchange ideology, contribute to users' varied perceptions of AI fairness. Through …

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Sustainability And Careers In The 21st Century, Phyllis J. Schoen, Amanda Baker Mar 2024

Sustainability And Careers In The 21st Century, Phyllis J. Schoen, Amanda Baker

Sustainability Research & Practice Seminar Presentations

Phyllis Schoen and Amanda Baker of the West Chester University Career Center present on "Sustainability and Careers in the 21st Century."

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Algorithmic Harms In Child Welfare: Uncertainties In Practice, Organization, And Street-Level Decision-Making, Devansh Saxena, Shion Guha Mar 2024

Algorithmic Harms In Child Welfare: Uncertainties In Practice, Organization, And Street-Level Decision-Making, Devansh Saxena, Shion Guha

Health Services and Informatics Research

Algorithms in public services such as child welfare, criminal justice, and education are increasingly being used to make high-stakes decisions about human lives. Drawing upon findings from a two-year ethnography conducted at a child welfare agency, we highlight how algorithmic systems are embedded within a complex decision-making ecosystem at critical points of the child welfare process. Caseworkers interact with algo rithms in their daily lives where they must collect information about families and feed it to algorithms to make critical decisions. We show how the interplay between systemic mechanics and algorithmic decision making can adversely impact the fairness of the …

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Potential Metabolite Biomarkers Of Multiple Sclerosis From Multiple Biofluids, Fatema Bhinderwala, Heidi E. Roth, Mary Filipi, Samantha Jack, Robert Powers Mar 2024

Potential Metabolite Biomarkers Of Multiple Sclerosis From Multiple Biofluids, Fatema Bhinderwala, Heidi E. Roth, Mary Filipi, Samantha Jack, Robert Powers

Robert Powers Publications

Multiple sclerosis (MS) is a chronic and progressive neurological disorder without a cure, but early intervention can slow disease progression and improve the quality of life for MS patients. Obtaining an accurate diagnosis for MS is an arduous and error-prone task that requires a combination of a detailed medical history, a comprehensive neurological exam, clinical tests such as magnetic resonance imaging, and the exclusion of other possible diseases. A simple and definitive biofluid test for MS does not exist but is highly desirable. To address this need, we have employed NMR-based metabolomics to identify potentially unique metabolite biomarkers of MS …

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N-H Nhc Palladium Catalysts Derived From Unique 2-Phosphinoimidazole Precursors For C-C Cross Coupling Reactions And Application Of Slow Releasing Polymers Impregnated With Gibberellic Acid To Overcome Seed Dormancy For Land Reclamation, Alexandra Jean Setelin Larson Mar 2024

N-H Nhc Palladium Catalysts Derived From Unique 2-Phosphinoimidazole Precursors For C-C Cross Coupling Reactions And Application Of Slow Releasing Polymers Impregnated With Gibberellic Acid To Overcome Seed Dormancy For Land Reclamation, Alexandra Jean Setelin Larson

Theses and Dissertations

Organometallic chemistry is highly dependent upon the ligands which are employed on a metal's surface. These ligands control steric bulk and electronics of the metal center which can change the reactivity of the organometallic complex. Ligands that are standard in organometallic chemistry include phosphine ligands. These phosphine ligands have been utilized in the field since the 1960's and have shaped the development of many key organometallic catalysts. Phosphine ligands are easily functionalized and highly reactive. This increased reactivity, however, causes severe limitations as phosphine ligands are often unstable under standard benchtop conditions and must be handled both air and moisture …

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Challenges On Public Security System In Ai Era—Preface For Special Column “Artificial Intelligence And Public Security”, Juan Cao, Qiang Sheng, Guojie Li Mar 2024

Challenges On Public Security System In Ai Era—Preface For Special Column “Artificial Intelligence And Public Security”, Juan Cao, Qiang Sheng, Guojie Li

Bulletin of Chinese Academy of Sciences (Chinese Version)

The rapid development of artificial intelligence generated content (AIGC) technology has triggered new public security risks, posing a serious threat to national security and social stability. This study exhibits the recent advances of artificial intelligence (AI) content generation and detection techniques, points out the challenges of detection techniques in real-world scenarios, and advocates that it is necessary to develop AIGC detection technology for public security needs and build a whole-process detection technology system from generative models to online platforms, which supports AIGC to be labeled at the generation phase, identifiable during dissemination and source-traceable after the incident occurs.

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