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Etude Des Deux De La Nutrition Azotee Du Trefle Blanc (Trifolium Repens L.): Activite De La Nitrogenase Et De La Nitrate Reductase, D Schontz, C Robin, A Guckert Apr 2025

Etude Des Deux De La Nutrition Azotee Du Trefle Blanc (Trifolium Repens L.): Activite De La Nitrogenase Et De La Nitrate Reductase, D Schontz, C Robin, A Guckert

IGC Proceedings (1977-2023)

L'importance des deux voies de la nutrition azotee (assimila­tion de l'azote combine et moleculaire) du trefle blanc n'a ete etudiee qu'en terme de bilans 15N (Haystead et Lowe, 1977). L'objet de cette etude est de suivre la cinetique des activites de la nitrate reductase et de la nitrogenase au cours du cycle de developpement en presence de differentes concentrations en nitrates.


Effets Di Nitrate Sur La Croissance Et La Fixation D’Azote Chez Le Trefle Blanc (Trifolium Repens L.): Importance De La Souche De Rhizobium, D Schontz, C Robin, D Laurentie, A Guckert Apr 2025

Effets Di Nitrate Sur La Croissance Et La Fixation D’Azote Chez Le Trefle Blanc (Trifolium Repens L.): Importance De La Souche De Rhizobium, D Schontz, C Robin, D Laurentie, A Guckert

IGC Proceedings (1977-2023)

Des apports d'azote combine sur des associations graminees­trefle blanc provoquent souvent un desequilibre favorable a la graminee. Cet effet peut etre attribue a une moindre competiti­vite de la legumineuse pour prelever l'azote combine (difference d'exploration du sol par le systeme racinaire) mais aussi a une moindre action de l'azote sur la croissance, du fait de !'inhibi­tion de la fixation. L'objet de cette etude est de tester !'influence de la souche de Rhizobium sur la sensibilite de la fixation d'azote et sur !es consequences de cette sensibilite sur la croissance du trefle en presence de differents niveaux de nitrates.


Leaf Growth In Lolium Perenne L., H Schnyder, S Seo, W Kuhbauch Apr 2025

Leaf Growth In Lolium Perenne L., H Schnyder, S Seo, W Kuhbauch

IGC Proceedings (1977-2023)

Knowledge about the spatial distribution of growth rates within the growth zone of leaves is essential for the study of metabolism associated with the growth process (Silk 1984). Such data have been described for Festuca arundinacea Schreb. during the phase of rapid blade elongation (Schnyder and Nelson 1987, 1988) and Zea mays L. during one developmental stage (Hsiao et al. 1985). No developmental studies appear to have been made. This paper describes the spatial distribution of growth rates within the elongation zone of L. perenne leaves from shortly after tip emergence to shortly before cessation of leaf growth. Special …


Analysis Of The Aerial Part And Roots Of The Lucerne Crop To Improve The Breeding Method, P Rotili, L Zannone, G Gnocchi, S Proietti, C Scotti Apr 2025

Analysis Of The Aerial Part And Roots Of The Lucerne Crop To Improve The Breeding Method, P Rotili, L Zannone, G Gnocchi, S Proietti, C Scotti

IGC Proceedings (1977-2023)

In our research work we consider the lucerne crop as a « system», that means a set of elements with their reciprocal relationships (Rotili 1988). The elements of such a system are the plants ; the whole of their relationships is called the « structure » of the system ; it is expressed by the effects caused by the reciprocal interference among the plants on their mor­phology and physiology. Both these constituents of the system (the plants and the structure) have to be considered by the breeder to improve the lucerne crop. From some hundred experiments established with material genetically …


Relationship Of Leaf Export Of Carbohydrate To Rhizomatous Growth In Panicum Amarum L., D S. Fisher, J C. Burns, D H. Timothy, K R. Pond Apr 2025

Relationship Of Leaf Export Of Carbohydrate To Rhizomatous Growth In Panicum Amarum L., D S. Fisher, J C. Burns, D H. Timothy, K R. Pond

IGC Proceedings (1977-2023)

Rhizomatous growth is desirable in pastures, yet many species used for grazing have exceedingly short rhizomes. In damaged pastures, vigorous rhizomes can provide for recovery of areas in which the stand has been lost. In breeding pasture grasses, selecting for high yields in a favorable environment may result in altered partitioning of carbohydrate between shoots and roots to favor above ground growth. In the Panicum genus, this can occur even in spaced plantings in which plants may exceed 2 m in height. The following experiment utilized a high rhizome (HR), an intermediate rhizome (IR), and a low rhizome (LR) accession …


Morphological And Physiological Growth Aspects Of Three Tropical Grasses, J A. Gomide Apr 2025

Morphological And Physiological Growth Aspects Of Three Tropical Grasses, J A. Gomide

IGC Proceedings (1977-2023)

Forage plants differ considerably regarding their ability to recover from grazing. Forage regrowth is determined by shoot apex survival (Sheard and Winch, 1966); leaf area (Ward and Blaser, 1961) ; non-structural carbohydrate content (Ward and Blaser, 1961 ; Brown and Blaser, 1965) and tillering potential (Paulsen and Smith, 1969). Little is known about these concepts regarding tropical grasses.


The Morphological Relation In The Panicle Of Panicum Maximum Jacq. Consequences On The Pollination And The Fertility, M Noirot Apr 2025

The Morphological Relation In The Panicle Of Panicum Maximum Jacq. Consequences On The Pollination And The Fertility, M Noirot

IGC Proceedings (1977-2023)

In Panicum maximum, the fertility is often low : 9 to 40 % (Warmke, 1951; Javier, 1970). At the Agricultural station of Man (Ivory Coast) - a limit region for natural dispersion of guinea grass -, the same amplitude has been noted. But our observations showed a negative correlation between fertility and panicle length. The study of the spikelet distribution into the sheathed panicle and its factors of variability bring an answer to explain this phenomenon.


Phytochrome Mediated Effects On White Clover Morphogenesis, C Varlet-Grancher, B Moulia, R Jacques Apr 2025

Phytochrome Mediated Effects On White Clover Morphogenesis, C Varlet-Grancher, B Moulia, R Jacques

IGC Proceedings (1977-2023)

The balance of a white clover-grass mixture mostly depends on the morphogenesis of white clover under conditions of compe­tition for light (Beinhart, 1963 ; Gastal et al., 1986). Within the recent years, emphasis has been placed on the role of phytochrome as a shade sensor and as a controlling system for the morphogen­esis of light-grown higher plants (Morgan and Smith, 1979). To our knowledge there is only one report on white clover photomorphogenesis available in the literature. This work (Solan­garrachchi and Harper, 1987) deals with the effect of chlorophyl­lian shade on morphogenesis and the effects obtained are some­times contradictory within …


White Clover Root Systems And Their Influence On The Survival Of Perennial Pastures In South Africa, A Smith, D.C W. Goodenough, A.R J. Morrison, Marie F. Smith Apr 2025

White Clover Root Systems And Their Influence On The Survival Of Perennial Pastures In South Africa, A Smith, D.C W. Goodenough, A.R J. Morrison, Marie F. Smith

IGC Proceedings (1977-2023)

The eastern part of the Republic of South Africa receives a relatively high rainfall, which results in it having a high agricul­tural potential. The quality of natural and cultivated pastures can be vastly improved by the introduction of a legume component. In the areas where pastures are likely to develop, the soils are acid and highly leached. White clover is not normally tolerant of low P, low Ca and high Al soil contents, and due to its nor­mally shallow rooting habit it consequently suffers easily from drought conditions, and therefore has a much reduced pro­ductive period of approximately 30 months …


Effect Of Interspecific Competition On The Development And Early Growth Of Grass Species, U R. Sangakkara, E Roberts Apr 2025

Effect Of Interspecific Competition On The Development And Early Growth Of Grass Species, U R. Sangakkara, E Roberts

IGC Proceedings (1977-2023)

In a sown pasture, each individual plant tries to gain access to growth resources for its establisment and development. The more competitive species, which generally exhibits more exten­sive seedling growth obtains a greater share of resources, thus modifying the environment within the plant community (Black, 1966). This develops competitive relationships. As competition operates essentially at the individual plant level (Rhodes, 1970), experiments need to study the effect of neighbouring species on the growth and development of a single plant (Mead, 1979). Studies on competition between ryegrass (Lolium perenne), prairiegrass (Bromus catharticus) and cocksfoot (Dactylis glomerata …


Azote Et Equilibre De L’Association Ray-Grass Anglias-Trefle Blanc, J C. Simon Apr 2025

Azote Et Equilibre De L’Association Ray-Grass Anglias-Trefle Blanc, J C. Simon

IGC Proceedings (1977-2023)

Bon nombre d'eleveurs s'interrogent sur l'interet des apports d'azote sur les associations ray-grass anglais - trefle blanc, en particulier sur la premiere pousse de printemps. Ces apports conduisent generalement a un desequilibre de !'association en faveur du ray-grass et compromettent de ce fait la perennite du melange. Apres avoir rappele brievement par quelques resultats experimentaux les principales incidences de l'azote sur le niveau de production et sur la composition de la culture mixte, nous analyserons les effets de l'azote sur l'equilibre de !'association a la lumiere des donnees recentes sur la morphogenese des deux plantes.


The Effects Of Coconut Palms On Pasture Understory, R W. Snaydon, D.N S. Fernando, R Sangakkara Apr 2025

The Effects Of Coconut Palms On Pasture Understory, R W. Snaydon, D.N S. Fernando, R Sangakkara

IGC Proceedings (1977-2023)

Pastures are extensively grown under coconut palms, and mainly grazed by cattle (Plucknett, 1979). The main advantages of this form of mixed cropping are : (a) diversification of products, (b) additional income, (c) feed for draft animals, (d) weed control, and (e) more rapid nutrient cycling. Surprisingly little information is available on the effects of pastures and coconut palms on each other (Plucknett, 1979) ; even less is known about the mechanisms of competition between them. This study was designed to study the effects of coconut palms on pasture. A trenching technique was used to investigate the effects of below-ground …


Compatibility Of Birdsfoot Trefoil With Tall Fescue Selected For High And Low Leaf Area Expansion Rate, C J. Nelson, K M. Hasson, D A. Sleper, J R. Forwood Apr 2025

Compatibility Of Birdsfoot Trefoil With Tall Fescue Selected For High And Low Leaf Area Expansion Rate, C J. Nelson, K M. Hasson, D A. Sleper, J R. Forwood

IGC Proceedings (1977-2023)

Tall fescue (Festuca arundinacea Schreb.) populations were selected for slow and rapid leaf area expansion rate (Nelson and Sleper, 1983). Daily leaf elongation rate (LER) in the field was increased by 0.30 mm and decreased by 0.53 mm per gener­ation (Nelson et al., 1985), but single-leaf photosynthesis was not affected. Populations selected for high LER had longer and wider leaf blades (Nelson and Sleper, 1983), and lower tiller density, higher weight per tiller, and higher forage yield in veg­etative swards (Nelson et al., 1985) than those selected for slow LER. Zarrough et al. (1983) suggested that tall fescue could …


Determination Of Predictive Zones For The Evaluation Of Herbage Grasses In Cuba, J Gerardo, Hilda Machado, Verena Torres Apr 2025

Determination Of Predictive Zones For The Evaluation Of Herbage Grasses In Cuba, J Gerardo, Hilda Machado, Verena Torres

IGC Proceedings (1977-2023)

Regional studies that evolve a high quantity of environment are made nowadays in order to define the behaviour of a geno­type in different environments, but the workers of introduction programmes can not prove their varieties in all environments. Therefore, it is necessary to select a wide range to represent production conditions. This topic has been studied by several writers (Rambling et al., 1980; Brown et al., 1983). The objec­tive of our study is to reduce test sites due to the high source in income needed in these studies.


Varieties Evaluation Of Lucerne (Medicago Sativa) With Different Winter Dormancy Class, O A. Bruno, R J. Leon, L A. Romero, O R. Quaino Apr 2025

Varieties Evaluation Of Lucerne (Medicago Sativa) With Different Winter Dormancy Class, O A. Bruno, R J. Leon, L A. Romero, O R. Quaino

IGC Proceedings (1977-2023)

Lucerne, pure or as a component of mixtures, is the forage more used in many regions of Argentine. In the central part of Santa Fe province it is the basis of feeding in the milk pro­duction systems. The diffusion of this species was done by mean of popula­tions, that at the beginning of this century produced forage of high yield, quality and good persistency. Later, the area ofland cultivated fluctuated, characterized by periods of diminishing and recovery. From 1969 the appearance of Pea aphid (Acyr­thosiphum pisum) gave rise to a critical situation. The solution to this problem was …


L’Effet Du Climat Sur La Production Des Herbages, I Vinczeffy Apr 2025

L’Effet Du Climat Sur La Production Des Herbages, I Vinczeffy

IGC Proceedings (1977-2023)

Dans les regions arides on peut optimiser la production des herbages par une technologie adaptee au climat, meme dans des sols pauvres. Le climat de la Hongrie est en grande partie sec, Jes sols des herbages sont defavorables, la vegetation est degra­dee et l'effet des engrais est modere. Le rapport entre le climat et la production est presente par Jes donnees du ne traitement d'une experience de 9 ans.


Effects Of Temperature And Photoperiod On The Extension Growth Of Six Temperate Grasses, G.A Van Esbroeck, Jane R. King, V S. Baron Apr 2025

Effects Of Temperature And Photoperiod On The Extension Growth Of Six Temperate Grasses, G.A Van Esbroeck, Jane R. King, V S. Baron

IGC Proceedings (1977-2023)

In western Canada late season pasture yields vary consider­ably among species. During August and early September yields of Bromus riparius and Dactylis glomerata are double that of the more commonly grown Bromus inermis (Knowles and Sonmore, 1985). The importance of leaf area to crop growth rate pnor to canopy closure is well documented (Rhodes, 1973). Two components of leaf area are the final size of leaves and the rate of leaf appearance, with final size of leaves largely dependant on the rate of extension and duration of extension (Edwards, 1967). Since the maturity of a leaf is closely associ­ated with …


C-4 Grass With Legumes: An Energy Efficient Biomass System, C J. Kaiser Apr 2025

C-4 Grass With Legumes: An Energy Efficient Biomass System, C J. Kaiser

IGC Proceedings (1977-2023)

Converting solar energy into biomass is theoretically most energy efficient when species of a high photosynthetic capacity are grown and nitrogen is furnished via symbiotic fixation. Per­ennial warm season grasses with the C-4 photosynthetic path­way outyield perennial cool season grasses that possess less efficient C-3 pathways. Growing a productive perennial warm season grass in sequence with a winter annual legume should increase yearly capture of solar energy per unit area. The different seasonal growth patterns of the winter legume and the C-4 grass should result in less inter-species competition than occurs in traditional cool season grass-legume combinations. As a result, …


Preliminary Rate Of Growth Curves For Legume Based Improved Pastures In The Mid-Altitude Region Of Yunnan Province Of Southern China, J R. Bruce-Smith, Yang Guo-Rong, Huang Bi-Zhi, Li Ji-Xin Apr 2025

Preliminary Rate Of Growth Curves For Legume Based Improved Pastures In The Mid-Altitude Region Of Yunnan Province Of Southern China, J R. Bruce-Smith, Yang Guo-Rong, Huang Bi-Zhi, Li Ji-Xin

IGC Proceedings (1977-2023)

Yunnan Province in south west China is very mountainous and has several major climatic/ecological zones ranging from tropical to alpine but all are dominated by the south Asian monsoonal rainy season. Extensive tracts of hilly depleted range lands occur in the mid-altitude zone (1800-2500 m) that are potentially suitable for developing to improved legume based pastures. Results of investigations as to suitable species and appropriate fertilizers for this purpose have been discussed previously (Mathison et al., 1985 and Wang et al., 1985). The Project has succesfully established model farms at several places throughout the Province and these carry reasonably pro­ductive …


Effects Of Low Temperature On Germination Of Herbage Species Used In New Zealand, J.F L. Charlton, J G. Hampton Apr 2025

Effects Of Low Temperature On Germination Of Herbage Species Used In New Zealand, J.F L. Charlton, J G. Hampton

IGC Proceedings (1977-2023)

In recent years, New Zealand's grassland industry has been diversified by the farming of different livestock types, and by using a wider range of pasture species. Some of the latter have establishment and growth patterns very different from the herbage species perennial ryegrass (Lolium perenne L.) and white clover (Trifolium repens L.), used traditionally by New Zealand farmers. Successful seedling establishment is critical for subsequent successful performance in a pasture. Quality of herbage seed is judged by thousand seed weight, analytical purity, freedom from undesirable weed seed contamination, and high germi­nation capacity. Internationally accepted procedures are used to …


Spanish Subclover Ecotypes: Evaluation Under Grazing, L Olea, C Bueno, J Paredes, P Verdasco Apr 2025

Spanish Subclover Ecotypes: Evaluation Under Grazing, L Olea, C Bueno, J Paredes, P Verdasco

IGC Proceedings (1977-2023)

The introduction of australian subclover varieties in the mediterranean environments of Europe has had irregular results (Olea et al., 1985). For this reason, important projects in selection and genetic improvement of subclover varieties adapted to these environments are carried out in Spain, Portu­gal and Sardinia. The selection program used at Badajoz (Spain) has origi­nated ecotypes which have been described by Gomez Pitera (1985) and Gonzalez et al. (1986). These ecotypes have short cycles, high level of hardseedness, high seed production and long flowering period. The final stage in the selection of pasture plants must include the evaluation under grazing. Subclover …


Behaviours Of Annual And Perennial Grass Species In The Same Genus, Y Takasaki, A Isoda, H Nojima, H Oizumi Apr 2025

Behaviours Of Annual And Perennial Grass Species In The Same Genus, Y Takasaki, A Isoda, H Nojima, H Oizumi

IGC Proceedings (1977-2023)

A genus including crop species usually has annual and peren­nial species. Although life history is genetically controlled, it is not fully investigated how it is expressed (Nooden, 1980; Woolhouse, 1982). We examined the behaviours of annuals and perennials in the genera Avena, Hordeum, Lolium and Oryza.


Vegetative Growth And Development Of Norwegian Poa Pratensis L. Ecotypes As Influenced By Temperature And Photoperiod, T S. Aamlid Apr 2025

Vegetative Growth And Development Of Norwegian Poa Pratensis L. Ecotypes As Influenced By Temperature And Photoperiod, T S. Aamlid

IGC Proceedings (1977-2023)

Temperature and photoperiod are the main environmental factors affecting flower induction in Poa pratensis (Heide, 1980). As all tillers have a juvenile stage, seed yield depends on both number and size of tillers at the end of the previous growth season. Furthermore, most of the seeds are produced on aerial shoots from the rhizome system (Borg, 1974). Thus, the aim of the experiment was to examine the influence of tem­perature and photoperiod on growth and development of various ecotypes.


Solving The Structure Of An Ancestral Protein Tyrosine Phosphatase, Natalie Turcsanski, Edna Armah Apr 2025

Solving The Structure Of An Ancestral Protein Tyrosine Phosphatase, Natalie Turcsanski, Edna Armah

Student Research Symposium

Protein tyrosine phosphatases (PTPs) regulate cell signaling by removing phosphate groups from tyrosine residues. Malfunction of these enzymes can lead to diseases such as diabetes and cancer. A conserved feature among PTPs is the catalytic acid loop, essential for phosphate removal. Computational analysis of PTP structures revealed that ancestral PTPs have considerable variation in conformations of this loop, sparking interest in their further study. The Asgard group, identified as ancestral to eukaryotic PTPs, was successfully expressed and purified under optimized conditions. Current efforts focus on optimizing crystallization to obtain larger crystals for structural analysis. This project will investigate the allosteric …


Determining The Function Of Type Iv-B Crispr-Cas Systems, Eric Jenkins, Brendon Guinn Apr 2025

Determining The Function Of Type Iv-B Crispr-Cas Systems, Eric Jenkins, Brendon Guinn

Student Research Symposium

CRISPR-Cas systems are a diverse group of prokaryotic adaptive immune systems that defend against Mobile Genetic Elements (MGEs) such as bacteriophages and plasmids. CRISPR-associated (Cas) proteins bind to guide RNAs (crRNAs) transcribed from a DNA repeat array (CRISPR array) containing spacers complementary to MGEs. Upon infection by a MGE, the Cas protein-crRNA complex binds to the target sequence in the invaders genome and cleaves the nucleic acid.


Comparative Analysis Of Vertical And Horizontal Subsurface Flow Constructed Wetlands For Eutrophication Mitigation", Ali M. Ahmed Apr 2025

Comparative Analysis Of Vertical And Horizontal Subsurface Flow Constructed Wetlands For Eutrophication Mitigation", Ali M. Ahmed

Al-Bahir

Constructed wetlands (CWs) serve as a sustainable and eco-friendly solution for wastewater treatment, particularly in the removal of eutrophication-causing pollutants. This review focuses on the comparative performance of Vertical Flow (VF) and Horizontal Flow (HF) Subsurface Flow (SSF) systems, assessing their efficiency in removing Biochemical Oxygen Demand (BOD), Chemical Oxygen Demand (COD), Total Nitrogen (TN), and Total Phosphorus (TP). VF systems demonstrate superior pollutant removal, particularly for nitrogen, due to enhanced aeration and efficient oxygenation processes. In addition, their compact design reduces land area requirements, making them advantageous in space-limited applications. Conversely, HF systems are more effective at supporting nutrient …


Aqueous Extracts Of Zingiber Officinale Rhizomes And Hibiscus Sabdariffa Leaves Enhanced Plasmodium Berghei-Infected Mice's Hematological Parameters., Fatimah Aluko Abubakar, Raliat Abimbola Aladodo, Aremu Abubakar Apr 2025

Aqueous Extracts Of Zingiber Officinale Rhizomes And Hibiscus Sabdariffa Leaves Enhanced Plasmodium Berghei-Infected Mice's Hematological Parameters., Fatimah Aluko Abubakar, Raliat Abimbola Aladodo, Aremu Abubakar

Al-Bahir

Malaria remains a global health challenge, leading to severe hematological complications. Natural alternatives such as Zingiber officinale and Hibiscus sabdariffa, known for their antioxidant and bioactive properties, are being investigated for their therapeutic potential. This study examines the hematological benefits of Z. officinale and H. sabdariffa in mice infected with the common malaria research model, NK65 chloroquine-sensitive Plasmodium berghei. Forty-two albino mice, averaging 24.5 ± 1.23g, were randomly divided into six groups. Mice in group A were uninfected which served as the normal control group. Mice in groups B, C, D, E, and F were inoculated intraperitoneally with P. …


Comparing Thermal Imaging Of New York City From 1988 To 2025, Amelia R. Slaton Apr 2025

Comparing Thermal Imaging Of New York City From 1988 To 2025, Amelia R. Slaton

Scholars Week

My project compared the urban heat island effect on New York City from 1988 to 2025. After looking at the risks associated with the heat island effect on local life I compared Landsat 5 imaging from 1988 and 1989 to Landsat 9 imaging from 2025 to find any differences between the thermal output of New York City. I then used images from both inner and long island area of New York from both time periods. As well as, the reason for New York's large thermal output compared to other surrounding areas and what the city is doing to combat the …


Detection Of Co2 Locally Generated By Formate Dehydrogenase Using Carbonate Ion-Selective Micropipette Electrodes, Seol Baek, Salvador Gutierrez-Portocarrero, Rokas Gerulskis, Shelley D. Minteer, Sean R. German, Henry S. White Apr 2025

Detection Of Co2 Locally Generated By Formate Dehydrogenase Using Carbonate Ion-Selective Micropipette Electrodes, Seol Baek, Salvador Gutierrez-Portocarrero, Rokas Gerulskis, Shelley D. Minteer, Sean R. German, Henry S. White

Chemistry Faculty Research & Creative Works

Many technologies involve immobilizing catalysts such as enzymes on surfaces, and the catalytic activities or functional efficiencies of these surface-bound catalysts can vary depending on orientations, localized binding sites, active sites, and intrinsic molecular nature. Accurate and rapid quantification of reaction products from surface-immobilized catalysts is crucial for understanding the selectivity, mechanisms, and reaction dynamics of catalytic systems and for revealing heterogeneous catalytic activities and reaction sites for applications such as biosensors and energy conversion/generation systems. Here, we demonstrate the feasibility of localized enzymatic activity measurements using microscale carbon dioxide (CO2)-sensitive ion-selective electrode (ISE) pipettes (0.5-2.5 μm tip …


Prenatal Exposure To Pm2.5 Concentration And Risk Of Preterm Birth In New Mexico; A Seasonal Pattern And Spatio-Temporal Modeling., Onyedikachi J. Okeke Apr 2025

Prenatal Exposure To Pm2.5 Concentration And Risk Of Preterm Birth In New Mexico; A Seasonal Pattern And Spatio-Temporal Modeling., Onyedikachi J. Okeke

Mathematics & Statistics ETDs

This study investigates the association between prenatal PM2.5 exposure and preterm birth risk in New Mexico (2014–2021). Using descriptive statistics, time series models, and spatial analyses, findings show an average preterm birth rate of 14.87 per 1,000 live births, with moderate correlation (r = 0.727) between PM2.5 levels and very preterm births. While traditional models revealed no significant global effect, spatial methods such as Geographically Weighted Regression (GWR) and Multiscale GWR uncovered strong spatial heterogeneity. PM2.5 effects varied by county (coefficients: -0.00154 to 0.00150), with clustering evident in 2018–2019 (Moran’s I = 0.155–0.174). Results highlight the limitations of global models …