Physical Sciences and Mathematics Commons^™

Temporal Rainfall Trend Analysis In Different Agro-Ecological Regions Of Southern Africa, W. Mupangwa, R. Makanza, L. Chipindu, M. Moeletsi, S. Mkuhlani, F. Liben, I. Nyagumbo, M. Mutenje

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Rainfall is a major driver of food production in rainfed smallholder farming systems. This study was conducted to assess linear trends in (i) different daily rainfall amounts (<5, 5–10, 11–20, 21–40 and >40 mm∙day-1), and (ii) monthly and seasonal rainfall amounts. Drought was determined using the rainfall variability index. Daily rainfall data were derived from 18 meteorological stations in southern Africa. Daily rainfall was dominated by <5 mm∙day-1 followed by 5–10 mm∙day-1. Three locations experienced increasing linear trends of <5 mm∙day-1 amounts and two others in sub-humid region had increases in the >40 mm day-1 category. Semi-arid location experienced increasing trends in <5 and 5–10 mm∙day-1 events. A significant linear trend in seasonal rainfall occurred at two locations with decreasing rainfall (1.24 and 3 mm∙season-1). A 3 mm∙season-1 decrease in seasonal rainfall was experienced under semi-arid conditions. There were no apparent linear trends in monthly and seasonal rainfall at 15 of the 18 locations studied. Drought frequencies varied with location and were 50% or higher during the November–March growing season. Rainfall trends were location and agro-ecology specific, but most of the locations studied did not experience significant changes between the 1900s and 2000s.

Effect Of Moisture Stress On The Development Of False Codling Moth Thaumatotibia Leucotreta (Lepidoptera: Tortricidae) On Two Tomato Varieties, Esther Museo Patrick, Irene Koomen, Shepard Ndlela, John Mwibanda Wesonga

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False codling moth Thaumatotibia leucotreta (Meyrick) is a pest native to sub-Saharan Africa infesting over 100 plant species including tomato. Its survival and performance are influenced by changes in precipitation and stress-related biochemical changes in the host plant. Water availability for agricultural production continues to decline due to climate change affecting drought-sensitive crops like tomatoes. Little is known on host plant–insect interactions of T. leucotreta and tomato as influenced by moisture stress. Hence, our study tested the impact of different water holding capacities (WHC) (40%, 50%, 60%, 70%, and 90%) of plant growing media on the growth of Anna F1 …

Functional Land Cover Scale For Three Insect Pests With Contrasting Dispersal Strategies In A Fragmented Coffee-Based Landscape In Central Kenya, Gladys Mosomtai, Abdelmutalab G.A. Azrag, Régis Babin, Elfatih M. Abdel-Rahman, John Odindi, Onisimo Mutanga, Henri E.Z. Tonnang, Tobias Landmann, Guillaume David

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In the Eastern Africa highlands, the gradual transformation of natural ecosystems to smallholding coffee-based agrosystems has resulted in more fragmented landscapes. Major pests of coffee find appropriate living conditions leading to high infestation rates and the need for smallholder farmers to implement pest control measures. This study aims to understand the influence of landscapes on the ecology of three major coffee pests: the coffee berry borer (CBB), Hypothenemus hampei, and the Antestia bugs Antestiopsis thunbergii (ABT) and A. facetoides (ABF). The study was conducted on a typical smallholder coffee-based landscape in central Kenya. The pest abundance was assessed monthly for …

Model Application Of Entomopathogenic Fungi As Alternatives To Chemical Pesticides: Prospects, Challenges, And Insights For Next-Generation Sustainable Agriculture, Bamisope Steve Bamisile, Komivi Senyo Akutse, Junaid Ali Siddiqui, Yijuan Xu

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In the past few decades, the control of pests and diseases of cultivated plants using natural and biological measures has drawn increasing attention in the quest to reduce the level of dependence on chemical products for agricultural production. The use of living organisms, predators, parasitoids, and microorganisms, such as viruses, bacteria, and fungi, has proven to be a viable and sustainable pest management technique. Among the aforementioned, fungi, most importantly the insect-pathogenic species, have been in use for more than 150years. These include the most popular strains belonging to the genera Beauveria, Metarhizium, Isaria, Hirsutella, and Lecanicillium. Their application is …

Does A Bottom-Up Mechanism Promote Hypoxia In The Mississippi Bight?, Virginie Sanial, Willard S. Moore, Alan M. Shiller

Faculty Publications

The Mississippi Bight, east of the Mississippi River, is a complex coastal ecosystem that, like the better-known Louisiana Shelf to the west, experiences seasonal bottom water hypoxia. However, input of allochthonous nutrients from the Mississippi River to the Mississippi Bight appears to be limited, begging the question of what drives seasonal hypoxia in this system. Prior research has suggested submarine groundwater discharge (SGD) could be an overlooked component of the Mississippi Bight biogeochemical system. We thus examined the hypothesis that SGD provides a “bottom up” driver for seasonal hypoxia in this area. We used a multi-tracer approach based on known …

An Innate Preference Of Bumblebees For Volatile Organic Compounds Emitted By Phaseolus Vulgaris Plants Infected With Three Different Viruses, Netsai Margareth Mhlanga, Alex M. Murphy, Francis O. Wamonje, Nik J. Cunniffe, John C. Caulfield, Beverley J. Glover, John P. Carr

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Cucumber mosaic virus (CMV)-infected tomato (Solanum lycopersicum L.) plants emit volatile organic compounds (VOCs) attractive to bumblebees (Bombus terrestris L.), which are important tomato pollinators, but which do not transmit CMV. We investigated if this effect was unique to the tomato-CMV pathosystem. In two bean (Phaseolus vulgaris L.) cultivars, infection with the potyviruses bean common mosaic virus (BCMV) or bean common mosaic necrosis virus (BCMNV), or with the cucumovirus CMV induced quantitative changes in VOC emission detectable by coupled gas chromatography–mass spectrometry. In free-choice olfactometry assays bumblebees showed an innate preference for VOC blends emitted by virus-infected non-flowering bean plants …

Loren Haarsma - When Did Sin Begin?, Loren Haarsma

University Faculty Publications and Creative Works

Patrick Hamilton speaks to Calvin University Professor, Loren Haarsma, about the origins of sin and various ways to make sense of the doctrine of original sin in light of evolutionary origins. Other topics of conversation include psychology, free will and the theology of Saint Augustine.

Utah - Perry Port Of Entry 2020, University Of Denver

FEAT Heavy-Duty Vehicle Measurements

Relevant Publications

Environmental Science & Technology publication.

Utah DEQ Final Report

Washington - Feat Bridge Based Train Measurements 2012, University Of Puget Sound

Non-Road Vehicle Data

Relevant Publications

Atmospheric Environment Publication (2019)

Optimizing Interaction Between Crop Residues And Inorganic N Under Zero Tillage Systems In Sub-Humid Region Of Kenya, Kinyua Michael, Mucheru Muna Monicah, Bolo Peter, Kihara Job

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Conservation agriculture practices involving zero tillage and residue retention are promising nutrient management strategies for soil health restoration. Despite their potential positive impact on soil fertility, improved crop yields and increased revenues for smallholder farmers; their effect on nitrogen inputs and crop growth is not clearly understood. This may limit their potential as a nutrient management strategy that may remedy soil degradation and boost crop yields for farmers. This study investigated how different tillage practices, crop residues and inorganic nitrogen (N) options affect maize production, soil fertility and economics of smallholder farming systems. The study was conducted in a short-term …

Supplementary Files For "Creating A Universal Depth-To-Load Conversion Technique For The Conterminous United States Using Random Forests", Jesse Wheeler, Brennan Bean, Marc Maguire

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As part of an ongoing effort to update the ground snow load maps in the United States, this paper presents an investigation into snow densities for the purpose of predicting ground snow loads for structural engineering design with ASCE 7. Despite their importance, direct measurements of snow load are sparse when compared to measurements of snow depth. As a result, it is often necessary to estimate snow load using snow depth and other readily accessible climate variables. Existing depth-to-load conversion methods, each of varying complexity, are well suited for snow load estimation for a particular region or station network, but …

Data From: Yellow Air Day Advisory Study, Arthur J. Caplan

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Using a dataset consisting of daily vehicle trips, PM2.5 concentrations, along with a host of climactic control variables, we test the hypothesis that “yellow air day” advisories provided by the Utah Division of Air Quality resulted in subsequent reductions in vehicle trips taken during northern Utah’s winter-inversion seasons in the early 2000s. Winter inversions occur in northern Utah when climactic conditions are such that PM2.5 concentrations (derived mainly from vehicle emissions) become trapped in the lower atmosphere, leading to unhealthy air quality (concentrations of at least 35 µg/m3) over a span of what are called “red air days”. When concentrations …

From Farm To Fork: Crickets As Alternative Source Of Protein, Minerals, And Vitamins, Dorothy K. Murugu, Arnold N. Onyango, Alex K. Ndiritu, Isaac M. Osuga, Cheseto Xavier, Dorothy Nakimbugwe, Chrysantus M. Tanga

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Globally, there is growing interest to integrate cricket-based ingredients (flour) into food products to combat food and nutrition insecurity. However, there is lack of information on in-depth nutrient profile of the two cricket species (Scapsipedus icipe and Gryllus bimaculatus), which are the most widely consumed in Africa. Here we determined the nutrient composition of two cricket species and compared them with published records of key animal and plant sources. Our results revealed that the crude protein contents of S. icipe and G. bimaculatus were similar (56.8 and 56.9%, respectively) and comparable to those of animal protein sources. Both cricket species …

Replication Data For: Goehring Et Al., "The Transport History Of Alluvial Fan Sediment...", Nathan Brown

Earth & Environmental Sciences Datasets - Archive

This data repository contains: A) MATLAB source code B) Sample locations and chemical measurements used for Be-10 and C-14 analysis C) Dose recovery test results for luminescence protocol D) Sample locations and dosimetry information for luminescence samples.

Ultrahigh Resolution Ote-Ms Data For Ambient Daytime And Nighttime Aerosol And Ambient Fog Water From San Pietro Capofiume, Matthew Brege, Lynn Mazzoleni

Michigan Tech Research Data

This dataset and the methods used to obtain it are described in Chapter 3 of "EXTREME MOLECULAR DIVERSITY IN BIOMASS BURNING ATMOSPHERIC ORGANIC AEROSOL OBSERVED THROUGH ULTRAHIGH RESOLUTION MASS SPECTROMETRY" a Dissertation prepared by Matthew Brege and submitted as a Doctoral Thesis. This work can be accessed here: https://doi.org/10.37099/mtu.dc.etdr/927

Briefly, four days worth of concurrent daytime/nighttime aerosol and fog water samples were collected at San Pietro Capofiume in the Emilia Romagna region of Italy from 1-Dec to 4-Dec, 2015. The water soluble extracts of the aerosol filters and aliquots of the fog water were analyzed using ultrahigh resolution Orbitrap mass …

Leveraging Of Hyperspectral Remote Sensing On Estimating Biomass Yield Of Moringa Oleifera Lam. Medicinal Plant, Thulani Tshabalala, Elfatih M. Abdel-Rahman, Bhekumthetho Ncube, Ashwell R. Ndhlala, Onisimo Mutanga

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Moringa oleifera Lam. is a functional plant considered to be high in nutrients as well as medicinal properties, largely utilised in most of the developing countries. Therefore, early prediction of M. oleifera biomass yield is a valuable pre- and post-harvest planning strategy for ensuring a reliable supply of the plant products and for marketing purposes. Subsequently, the objective of the current study was to explore the potential use of hyperspectral data in predicting biomass yield of different cultivars of M. oleifera. Canopy hyperspectral data were collected on five M. oleifera cultivars when they were one month and two months old …

Liutex And Statistical Analysis For Fluid Transition, Charles Matthew Nehemiah Nottage

Mathematics Dissertations - Archive

A vortex can be intuitively recognized as the rotational swirling motion of the fluids. The fascination of this phenomenon brought about many years of research to define, classify, and identify the vortical structure. Throughout the decades, many vortex identification methods were developed and can be characterized into three generations. The generational methods are vorticity-based, eigenvalue-based such as Q, ��_ci, and ��_2, and Liutex-based. Before the development of Liutex, there was no mathematical definition for vortex. Is Liutex superior to vorticity and the eigenvalue-based methods? Is the vorticity vector the local rotational axis? Should vorticity be considered vortex? In this dissertation, …

Use Of Earth Observation Satellite Data To Guide The Implementation Of Integrated Pest And Pollinator Management (Ippm) Technologies In An Avocado Production System, Marian Adan, Elfatih M. Abdel-Rahman, Stella Gachoki, Beatrice W. Muriithi, H. Michael G. Lattorff, Vivian Kerubo, Tobias Landmann, Samira A. Mohamed, Henri E.Z. Tonnang, Thomas Dubois

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Insect pollinators provide an important ecosystem service by improving agricultural productivity. However, their populations have been declining in recent years due to excessive use of synthetic pesticides, climate and land use/land cover (LULC) changes. Climate and LULC changes have resulted in land fragmentation and consequently pollinator habitat loss. To conserve pollinators, there is a need for sustainable agricultural practices such as integrated pest and pollinator management (IPPM), which is a holistic landscape management approach that minimizes pesticides use while conserving pollinator abundance and diversity. This study aimed to use earth observation (EO) data to characterize landscape dynamics in terms of …

Temperature-Dependent Phenology Of The Parasitoid Fopius Arisanus On The Host Bactrocera Dorsalis, Samuel Nanga Nanga, S. Kekeunou, A. Fotso Kuate, K. K.M. Fiaboe, M. A. Dongmo Kenfak, H. E. Tonnang, D. Gnanvossou, C. Djiéto-Lordon, R. Hanna

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Fopius arisanus (Sonan), an egg-pupal parasitoid of numerous fruit fly species, was recently introduced into Africa for the control of the Oriental fruit fly, Bactrocera dorsalis (Hendel). In this study, life-table data of F. arisanus were generated under laboratory conditions at six constant temperatures (15, 20, 25, 30, 28 and 35 °C; 75% RH, L12:D12 photoperiod) and under variable conditions in a screenhouse on B. dorsalis. Several non-linear functions were fitted to model species development, mortality, longevity and oviposition using the Insect Life Cycle Modeling (ILCYM) software. The established phenology models were stochastically simulated at variable temperatures to estimate the …

Amplification Of Hidden Periodic Motions In 3d Videos, Thomas Boccuto, Seraiah Kutai, Kristen Mosley, Samuel Kirk

Mathematics Summer Fellows

Ordinary videos capture a surprising amount of hidden, visually imperceptible information. For instance, videos of peoples' faces may capture color changes in the skin and artery motion from heartbeats, while videos of mechanical systems can capture subtle vibrations indicating imminent failure. Algorithms can extract and exaggerate these signals for visualization on top of the original videos. In particular, Eulerian magnification algorithms sidestep the need to track hidden motions directly and instead devise multiscale bandpass filters to amplify signals in local spatial regions. In this work, we extend these techniques beyond color videos to geometric video data captured by 3D depth …

Differences In Seasons And Rice Varieties Provide Opportunities For Improving Nitrogen Use Efficiency And Management In Irrigated Rice In Kenya, Joseph P. Gweyi-Onyango, Winnie Ntinyari, Andrew Ogollaegesa, Richard Mose, Symon Njinju, Mekonnen Giweta, Cargele Masso

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Apart from nitrogen (N) rates, N use efficiency (NUE) (yield N/total input N) is affected by seasons, crop developmental stages, and varieties. Knowledge of how these factors affect NUE in rice production in Kenya is limited. Therefore, field experiments were conducted with 'low rates' of N (simulating farmers' practices) of 0, 26, 52 and 78 kg N ha-1 with five varieties (MWUR1, MWUR4, IRAT109, NERICA4 and NERICA10) and higher rates of N (125, 175, and 225 kg N ha-1) simulating researchers' doses with two lowland varieties (Basmati 370 and BW 196) and IR 72. Another experiment on NUE responses to …

Data From: 'Bottled' Spiro-Doubly Aromatic Trinuclear [Pd2ru]+ Complexes, Alexander I. Boldyrev, Maksim Kulichenko

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The central unit of the synthesized structure is a Ru atom which is the vertex of the [RuPd2]+ triangle being the first example of mixed triangles among these metals. Moreover, Ru is involved in both σ- and π-aromaticity. σ-aromaticity is realized as the d-AO based multicenter bond which is delocalized over the inner [RuPd2]+ triangle with considerable contribution from the sulfur electron density. Besides, transition metals are known to interact with the electron cloud of benzene which, in turn, leads to the charge transfer and formation of conjugated electron density between the TM and benzene. The second type of aromaticity, …

Data From: High-Resolution Photoelectron Imaging Of Irb3-: Observation Of A P-Aromatic B3+ Ring Coordinated To A Transition Metal, Alexander I. Boldyrev, Maksim Kulichenko

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In a high-resolution photoelectron imaging and theoretical study of the IrB3− cluster, two isomers were observed experimentally with electron affinities (EAs) of 1.3147(8) and 1.937(4) eV. Quantum calculations revealed two nearly degenerate isomers competing for the global minimum, both with a B3 ring coordinated with the Ir atom.

Data From: Periodic F-Defects On The Mgo Surface As Potential Single-Defect Catalysts With Non-Linear Optical Properties, Alexander I. Boldyrev, Maksim Kulichenko

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In this paper we suggest a new type of a single-atom (or single-defect) catalyst – MgO with periodic defects on the (0 0 1) surface – which possesses noticeable non-linear optical properties. Periodicity of these defects leads to the significant extensive increase in the activity of a catalyst by growth of the concentration of active sites. In this work we showed the presence of diffuse electride-like multi-center bonds inside every periodic F-center. We also discovered that MgO with periodic defects on the surface gains non-linear optical properties due to electride-like polarizable bonds inside every defect. And most importantly, such defective …

Data From: Hydrated Sulfate Clusters So4(2-)(H2o)N(N=1-40): Charge Distribution Through Solvation Shells And Stabilization, Alexander I. Boldyrev, Maksim Kulichenko

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In the current work, we report our computational study of hydrated sulfate clusters SO4(2–)(H2O)n (n = 1–40) in order to understand the nature of stabilization of this important anion by water molecules. We showed that the most significant charge transfer from dianion SO4(2–) to H2O takes place at a number of H2O molecules n ≤ 7. The SO4(2–) directly donates its charge only to the first solvation shell and surprisingly, a small amount of electron density of 0.15|e| is enough to be transferred in order to stabilize the dianion.

Data From: Expansion Of Aromaticity Magnetic Criteria On Multi-Layer Structures. Magnetic Response And Spherical Aromaticity Of Matryoshka-Like [Sn@Cu12@Sn20]12- Cluster, Alexander I. Boldyrev, Maksim Kulichenko

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Structural characterization of the discrete [Sn@Cu12@Sn20]12− cluster exposed a fascinating architecture composed of three concentric structural layers in which an endohedral Sn atom is enclosed in a Cu12 icosahedron, which in turn is embedded in an Sn20 dodecahedron. Herein, the possibility of sustaining aromatic behavior for this prototypical multilayered species was evaluated, in order to extend this concept to more complex clusters on the basis of magnetic response and bonding analysis by the AdNDP approach. This revealed characteristic features of spherical aromatics, given by the ability to sustain the shielding cone property, similar to archetypal aromatics.

Data From: Σ-Aromaticity In The Mos2 Monolayer, Alexander I. Boldyrev, Maksim Kulichenko

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As is shown using the SSAdNDP approach, Mo and S form 2-centered bonds and there is a lone pair on each S. Most importantly, the remaining electrons are distributed over Mo atoms and form conjugated aromatic σ-bonds inside every hexagonal ring, which makes molybdenum the main carrier of σ-aromaticity.

Data From: Spherical Aromaticity In Inorganic Chemistry, Alexander I. Boldyrev, Maksim Kulichenko

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Chapter "14 - Spherical aromaticity in inorganic chemistry" in a book "Aromaticity - Modern Computational Methods and Applications"

Data From: Can Aromaticity Be A Kinetic Trap? Example Of Mechanically Interlocked Aromatic [2-5]Catenanes Built From Cyclo[18]Carbon, Alexander I. Boldyrev, Nikita Fedik

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Project reports the analysis of interlocked C18 rings as building blocks for polycatenanes.

Data From: Two Names Of Stability: Spherical Aromatic Or Superatomic Intermetalloid Cluster [Pd3sn8bi6]4−, Alexander I. Boldyrev, Nikita Fedik

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Project reports the aromaticity in the intermetalloid cluster [Pd3Sn8Bi6]4−.