Digital Commons Network^™

Defoliation And Water Deficit: Their Influence On Pasture Growth And Water Use Of White Clover, F. H. Santiñaque

IGC Proceedings (1977-2023)

With the objective of understanding the physiological basis of defoliation and water use relationships of white clover (Trifolium repens L.) pastures during water deficits, an experiment in controlled conditions was carried out. Outdoors nine liters pots were filled with a loam-clay soil with a water content at field capacity (FC), of 35%(w/w), at a bulk density of 1.1 g/cm³. Pre-germinated and inoculated clover seeds were transplanted, and the number of plants was adjusted to permit the development of full plant cover. The level of P in the soil did not limit plant establishment or growth. The …

Seasonal Botanical Composition And Available Forage Of Natural Grasslands In The Southeastern Range Region Of Rio Grande Do Sul, Brazil, J. C. L. Reis, H. Alfaya, O. J. W. Siqueira, C. B. Farias Jr.

IGC Proceedings (1977-2023)

The objective of the study was to verify the influence of climatic seasons on botanical composition and on available dry matter of grasslands in the physiographic region known as Serra do Sudeste (Southeastern Range), RS, Brazil. The climate is Cfb according to Koëppen`s classification. The experiment was conducted in two natural grasslands submitted to two pre-experimental stocking rates [area 1: 0.65 AU ha^-1 (normal grazing); area 2: over 2.0 AU ha^-1 (overgrazing); AU: Animal Unit = 500kg live weight]. Stocking rates throughout the experimental period (June 1996–July 1997) were 0.4 and 0.65 AU ha^-1, over winter …

Effect Of Sowing Time On Phytomass Production During Early Growth Of Two Varieties Of Stylosanthes Guianensis (Aubl.) Sw., M. L.S. Paterniani, T. J. D. Rodrigues, G. T. Pereira, L. R. A. Rodrigues

IGC Proceedings (1977-2023)

The objective of this research was to determine the effect of two sowing times on phytomass production of two varieties of Stylosanthes guianensis (var. pauciflora and var. vulgaris). Two experimental periods were studied (1: January - May/1998 and 2: November/1998 - March/1999) using a completely randomized factorial design 2 x 2 x 14 (two periods, two varieties and fourteen ages of evaluation), with four replications. The results showed a difference between the periods concerning the growth and development of Stylosanthes, and that period 2 was the most favourable to this forage plant. There was, also, different adaptability between …

Influence Of Water Stress On Protein Concentration In Themeda Triandra Forsk. In A Semi-Arid Climate Of South Africa, I. B. Oosthuizen, Hennie A. Snyman

IGC Proceedings (1977-2023)

The objective of this study was to determine the influence of four water treatments (T1 = 75-100%, T2 = 50-75%, T3 = 25-50% and T4 = 0-25% of Field Water Capacity) on the concentration of water-soluble protein as growth reserve during three growth stages (vegetative, pipe and reproductive) in three plant parts (roots, stubble and leafs). The water-soluble protein concentration (WSPC) in the plants under the four water treatments differed (P≤0.01) among the plant parts as well as among growth stages (P≤0.05). WSPC in leafs increased (P≤0.01) with increased water stress from T1 to T4 for the pipe growth stage. …

Effects Of Photoperiod, Low Temperature And N Nutrition On Vsp Accumulation In Taproot Of Alfalfa, J. C. Avice, C. Noquet, A. Ourry, J. J. Volenec

IGC Proceedings (1977-2023)

In Medicago sativa L., vegetative storage protein (VSP), specifically accumulated in taproot, are strongly involved in nitrogen storage. How the accumulation of such VSPs is regulated remains largely unknown. Experiments were designed with non-nodulated alfalfa to determine if length of the photoperiod, a decrease of temperature, or high availability of mineral nitrogen may induce the accumulation of VSPs. ¹⁵N labelling was used to quantify nitrogen uptake and its further relative translocation within the plant while VSPs accumulation was analysed by ELISA quantification. Results showed that environmental factors such as shortening daylength or low temperature changed biomass allocation within the …

Fructans From Elongating Leaf Bases Are A Source Of Carbon For Regrowth After Defoliation In Lolium Perenne, A. Morvan-Bertrand, J. C. Avice, M. P. Prud'homme

IGC Proceedings (1977-2023)

A detailed study of carbohydrate metabolism in perennial ryegrass (Lolium perenne L.) during the first 48 h of regrowth showed that the decline in fructan concentration occurred not only in the differentiation zone (30-60 mm from leaf base), but also in the elongation zone of the elongating leaf bases. Unlike other soluble carbohydrates, the net deposition rate of fructose remained positive and even rose during the first day following defoliation. FEH (fructan exohydrolase) activity, which was maximum in the differentiation zone before defoliation, increased in all segments but peaked in the elongation zone after defoliation. Taken all together, these …

Effect Of Climatic Factors On The Plant Population Dynamics In Temperate Pasture Implantation, B. Martin, R. Refi, S. Montico, M. Costanzo

IGC Proceedings (1977-2023)

The objective of this experiment was to determine the environmental influence on seedling emergence of alfalfa and fescue in mixture. We hypothesized that the temperature and precipitation data could be used to estimate field emergence of alfalfa and fescue. A field trial was carried out at Zavalla, Argentina and consisted of sowing a tall fescue – alfalfa mixture at different seeding date (March, April and June). Relationships between the range of temperature, rainfalls and alfalfa and fescue seedling emergence were described by linear regression models. Patterns of emergence and death of alfalfa and fescue seedling were found in the different …

Seed Production And Quality Of Buffelgrass (Cenchrus Ciliaris) Selections, N. F. G. Rethman, W. H. Boshoff

IGC Proceedings (1977-2023)

As seed production and quality are critical considerations in the commercialization of new cultivars, an evaluation programme of promising Cenchrus ciliaris (Buffelgrass) accessions placed particular emphasis on these parameters. Accessions identified for registration proved to be superior in both respects, although storage of seed or cleaning of fresh seed reduced the differences in germination between accessions. The refinement of seed cleaning processes should receive greater emphasis by commercial concerns.

Effect Of The Hierarchical Position Of Individuals In A Medicago Sativa Stand On Shoot Respiration, M. Lötscher, Hans Schnyder

IGC Proceedings (1977-2023)

The influence of the hierarchical position on the relationship between C gains and C losses (respiration) of individuals was investigated in a alfalfa (Medicago sativa) stand. The hierarchical position that an individual occupied was defined by its height relative to the stand height. Stands were established by arranging potted individual plants at a density of 400 plants m^-2. Stands were grown in growth cabinets. ¹³C steady-state labelling was used to assess C fixation (C_new) by individuals during a photoperiod of 16 h. Respiration of shoots was measured during the following 8 h dark …

Patterns Of Development And Nitrogen Reserves Mobilization During Regrowth Of Defoliated Clover, F. Le Dily, E. Goulas, P. Lainé, E. Le Deunff

IGC Proceedings (1977-2023)

Contribution of nitrogen reserves to regrowth following defoliation was studied in white clover plants (Trifolium repens) according to the morphological pattern of differentiation of the aerial parts during the same period. Low temperature and short day lengths were used as a pre-treatment in order to increase branching and enhance new sites of leaf production during a further 25 d period of regrowth. Pre-treated plants exhibited a large reduction in leaf area largely counterbalanced with a high increase in leaf pool size during the first 10 d of regrowth. The mobilization of nitrogen reserves during regrowth of defoliated clover …

Resistance To Drought In Shore Elurope (Aeluropus Litoralis) And Weeping Alkaligrass (Puccinellia Distans), Mohammad Jafari, A. G. Firouzabadi

IGC Proceedings (1977-2023)

Two rangeland grass species, Shore Elurope (Aeluropus litoralis) and Weeping Alkaligrass (Puccinellia distans) were studied. The research was done under a split plot experiment and completely randomized design. Plants were grown under two irrigation treatments (seven and fourteen day periods of irrigation treatments). Morphological response included determination of wilting percentage, leaf water potential, production of yield, root dry weight, weight ratio of root/stem and finally total dry weight of species. Anatomical studies included leaf descriptive structure such as comparison of stomata and their density in area unit, study of vascular structure, mesophyl tissues and epiderm. Results …

Management Of Large Cell Neuroendocrine Carcinoma, Virginia Corbett, Susanne M. Arnold, Lowell B. Anthony, Aman Chauhan

Internal Medicine Faculty Publications

Background: Large cell neuroendocrine carcinoma (LCNEC) is a rare, aggressive cancer with a dismal prognosis. The majority of cases occur in the lung and the gastrointestinal tract; however, it can occur throughout the body. Recently advances in the understanding of the molecular underpinnings of this disease have paved the way for additional novel promising therapies. This review will discuss the current best evidence for management of LCNEC and new directions in the classification and treatment of this rare disease.

Methods: We performed a PubMed search for “Large cell neuroendocrine carcinoma” and “High grade neuroendocrine carcinoma.” All titles were screened for …

Analysis Of Rock Varnish From The Mojave Desert By Handheld Laser-Induced Breakdown Spectroscopy, Russell S. Harmon, Daria Khashchevskaya, Michelle Morency, Lewis A. Owen, Morgan Jennings, Jeffrey R. Knott, Jason M. Dortch

Faculty, Staff, and Affiliated Publications--KGS

Laser-induced breakdown spectroscopy (LIBS) is a form of optical emission spectroscopy that can be used for the rapid analysis of geological materials in the field under ambient environmental conditions. We describe here the innovative use of handheld LIBS for the in situ analysis of rock varnish. This thinly laminated and compositionally complex veneer forms slowly over time on rock surfaces in dryland regions and is particularly abundant across the Mojave Desert climatic region of east-central California (USA). Following the depth profiling examination of a varnished clast from colluvial gravel in Death Valley in the laboratory, our in situ analysis of …

High Depth-Of-Discharge Zinc Rechargeability Enabled By A Self-Assembled Polymeric Coating, David J. Arnot, Matthew B. Lim, Nelson S. Bell, Noah B. Schorr, Ryan C. Hill, Andrew Meyer, Yang-Tse Cheng, Timothy N. Lambert

Chemical and Materials Engineering Faculty Publications

Zinc has the potential for widespread use as an environmentally friendly and cost-effective anode material pending the resolution of rechargeability issues caused by active material loss and shape change. Here, a self-assembled Nafion-coated Celgard 3501 (NC-Celgard) separator is shown to enable unprecedented cycle life of a Zn anode in alkaline electrolyte at high depth-of-discharge (DOD_Zn). Using commercially relevant energy-dense electrodes with high areal capacities of 60 mAh cm^–2, Zn–Ni cells tested at 20% DOD_Zn cells achieve over 200 cycles while 50% DOD_Zn cells achieve over 100 cycles before failure. The 20% and 50% DOD …

Genomic Data From Nsclc Tumors Reveals Correlation Between Shp-2 Activity And Pd-L1 Expression And Suggests Synergy In Combining Shp-2 And Pd-1/Pd-L1 Inhibitors, Keller J. Toral, Mark A. Wuenschel, Esther P. Black

Pharmaceutical Sciences Faculty Publications

The identification of novel therapies, new strategies for combination of therapies, and repurposing of drugs approved for other indications are all important for continued progress in the fight against lung cancers. Antibodies that target immune checkpoints can unmask an immunologically hot tumor from the immune system of a patient. However, despite accounts of significant tumor regression resulting from these medications, most patients do not respond. In this study, we sought to use protein expression and RNA sequencing data from The Cancer Genome Atlas and two smaller studies deposited onto the Gene Expression Omnibus (GEO) to advance our hypothesis that inhibition …

Dietary And Pharmacologic Manipulations Of Host Lipids And Their Interaction With The Gut Microbiome In Non-Human Primates, Jennifer M. Lang, Leslie R. Sedgeman, Lei Cai, Joseph D. Layne, Zhen Wang, Calvin Pan, Richard Lee, Ryan E. Temel, Aldons J. Lusis

Physiology Faculty Publications

The gut microbiome influences nutrient processing as well as host physiology. Plasma lipid levels have been associated with the microbiome, although the underlying mechanisms are largely unknown, and the effects of dietary lipids on the gut microbiome in humans are not well-studied. We used a compilation of four studies utilizing non-human primates (Chlorocebus aethiops and Macaca fascicularis) with treatments that manipulated plasma lipid levels using dietary and pharmacological techniques, and characterized the microbiome using 16S rDNA. High-fat diets significantly reduced alpha diversity (Shannon) and the Firmicutes/Bacteroidetes ratio compared to chow diets, even when the diets had different compositions …

A Randomized Controlled Trial To Determine Whether Beta-Hydroxy-Beta-Methylbutyrate And/Or Eicosapentaenoic Acid Improves Diaphragm And Quadriceps Strength In Critically Ill Mechanically Ventilated Patients, Gerald S. Supinski, Paul F. Netzel, Philip M. Westgate, Elizabeth A. Schroder, Lin Wang, Leigh Ann Callahan

Internal Medicine Faculty Publications

BACKGROUND: Intensive care unit acquired weakness is a serious problem, contributing to respiratory failure and reductions in ambulation. Currently, there is no pharmacological therapy for this condition. Studies indicate, however, that both beta-hydroxy-beta-methylbutyrate (HMB) and eicosapentaenoic acid (EPA) increase muscle function in patients with cancer and in older adults. The purpose of this study was to determine whether HMB and/or EPA administration would increase diaphragm and quadriceps strength in mechanically ventilated patients.

METHODS: Studies were performed on 83 mechanically ventilated patients who were recruited from the Medical Intensive Care Units at the University of Kentucky. Diaphragm strength was assessed as …

Allelopathic Influence Of Eragrostis Curvula Water Extract On Seed Germination And Seedling Growth Of Two Other Species, R. W. Coelho, R. E. Schmidt

IGC Proceedings (1977-2023)

Weeping lovegrass (Eragrostis curvula Schrad. Nees) is a very agressive tropical species and does not grow well with other species. This study was set up to investigate the allelopathic effect of various extract concentrations of weeping lovegrass on seed germination of white clover (Trifolium repens L.) and bentgrass (Agrostis stolonifera L.) and the seedling development of white clover. Labotatory and growth chamber studies were conducted. Extract concentrations of 13.6, 27.2, 40.8, 54.4, and 62.0 g/100mL of water were studied. Treatments were arranged in a completely ramdomized design with three replications. The allelopathic effect of weeping lovegrass was …

Effect Of Aging In Tillers Of Panicum Maximum On Leaf Elongation Rate, D. D. Carvalho, C. Matthew, J. Hodgson

IGC Proceedings (1977-2023)

Two cultivars of Guinea grass (P. maximum, Jacq.), Mombaça and Tanzânia, were cultivated in five litre pots, as single plants, in a green house. Plants were subjected to three defoliation levels (100, 200 and 400 mm height) for five successive monthly harvests. The experimental design was a 3x2 randomised block with five replicates. Three types of tiller (main, primary and secondary) were selected, at random, on each plant and leaf elongation rate (LER) above cutting height was measured, weekly, between harvests. There were significant differences (P < 0.05) in LER between tiller types in cv. Mombaça in all periods, but only in period two in cv. Tanzânia. In the last period tillers were classified, at random, as old (over four months age) mature (between two and four months) and young (between one and two months). Old tillers had a lower (P < 0.05) LER than the other two categories in both cultivars and lower (P < 0.05) SLA (specific leaf area) in Mombaça.

Dormant Bud Development In Phalaris Aquatica L., Brendan R. Cullen, P. E. Quigley, D. F. Chapman

IGC Proceedings (1977-2023)

The formation of dormant buds is critical to the summer survival of phalaris (Phalaris aquatica L.) in pastures. Dormant buds are formed on the base of reproductive tillers as they develop in spring. This project aimed to determine the seasonal pattern of dormant bud development and the influence of grazing management on bud dynamics. Approximately three buds per reproductive tiller were formed in the spring and early summer period. These buds responded to summer rainfall, with one third of buds becoming active following a 15-mm rainfall event in mid summer. In the following growing season, on average, 1.5 buds …

Tillering Dynamics Of Panicum Maximum Jacq. Cv. Tanzania-1 After Grazing, Rodrigo A. Barbosa, Domicio Nascimento Jr., Valéria P. B. Euclides, A. J. Regazzi, D. M. Fonseca

IGC Proceedings (1977-2023)

Tillering dynamics and tiller dry matter weight from Tanzania grass (Panicum maximum cv. Tanzania-1) were evaluated in two post-grazing stubbles (High Post-grazing Stubble – HPS-3.6 t of DM/ha and Low Post-grazing Stubble – LPS-2.3 t of DM/ha). There was no difference between post-grazing stubbles for decapitated axillary and basal remainder and new axillary tillers. The LPS presented greater number of new basal tillers. The rate of appearance of new basal and axillary tillers decreased with time after grazing. There were differences between the treatments on tiller dry matter weight, and greater values were found in the high post-graze stubble.

Flowering Distribution Pattern In White Clover Cultivars, B. S. Rosso, E. M. Pagano, P. Rimieri

IGC Proceedings (1977-2023)

A trial was carried out at Pergamino Agricultural Experimental Station to examine the distribution pattern and the profuseness of inflorescence production of white clover (Trifolium repens L.). The treatments were 16 cultivars (Churrinche, El Lucero MAG, Bayucuá, Estanzuela Zapicán, Lucero Plus Inta, Haifa, California, Ladino Gigante Lodigiano, Dubrava, Susi, Merwi, Blanca, Sonja, Espanso, Nora, S 184) of different origins and leaf size. The experimental design was a lattice with four replications. Southamerican cultivars showed a similar distribution pattern and had the highest inflorescence production. They also flowered earlier than foreign cultivars, except Haifa. Some of the cultivars evaluated did …

Breeding Italian Annual Ryegrass For Tolerance To Pythium Ultimum, L. R. Nelson, I. J. Pemberton, G. R. Smith

IGC Proceedings (1977-2023)

This study was conducted in an attempt to improve tolerance of annual ryegrass to Pythium ultimum Trow. Improved tolerance of ryegrass as measured in laboratory experiments was confirmed in greenhouse studies. This tolerance was defined as improved emergence and increased root length of seedlings in the presence of P. ultimum, using rolled germination paper in the laboratory, and sand in the greenhouse. Further experimentation will be required to determine usefulness of this selected trait under field conditions.

Suitable Seed Harvesting Time For Six Grass Species, Hossein Arzani, A. Fakhireh

IGC Proceedings (1977-2023)

Determination of the best period of seed harvesting was considered. Six grass species were selected. The research was conducted in three stations of Alborz, Sirachal and Homand Absard. According to maturing stages, seed collection for measuring seed water content (moisture content), weight of 1000 seeds and germination percentage has been done. The result showed that there were significant differences between harvesting time on seed germination for all species in all regions. Moisture content, germination rate, weight of 1000 seeds and seed shedding were important characteristics for determination of suitable seed harvesting time.

Effect Of Nitrogen Fertilizer On Reproductive Tiller Development In Perennial Ryegrass, I. Bahmani, E. R. Thom, C. Matthew, G. Lemaire

IGC Proceedings (1977-2023)

The objective of this study was to compare reproductive tiller development in two ryegrass (Lolium perenne L.) cultivars, when fertilized with nitrogen. Plots of the cultivars ‘Grasslands Ruanui’ and ‘Ellett’ ryegrass were sown in April 1996. Half of each plot received nitrogen fertilizer (30 kg N/ha) after each grazing by dairy cows from September 1996 to May 1997 and from October 1997 to April 1998. Ryegrass tiller dynamics was monitored from September 1996 to March 1998. The proportion of reproductive tillers in the total tiller population was higher, on average, over the first flowering period (October 1996 to January …

On Estimating Personality Traits Of Us Supreme Court Justices, Ryan C. Black, Ryan J. Owens, Justin Wedeking, Patrick C. Wohlfarth

Political Science Faculty Publications

Psychological scholarship on personality is uniting with political science to redefine existing theories. This is clearly the case with research on judicial behavior and the US Supreme Court. But if this new approach is to survive and thrive, it must employ measures equal to the task. We show that Supreme Court Individual Personality Estimates, which seek to estimate justices’ personalities by examining their concurring opinions, suffer from a number of important methodological deficits that critically limit their usefulness. We briefly discuss what kinds of improved personality measures scholars should use instead and offer an improved set of estimates for one …

Cognitive And Behavioral Domains That Reliably Differentiate Normal Aging And Dementia In Down Syndrome, Jordan P. Harp, Lisa M. Koehl, Kathryn L. Van Pelt, Christy L. Hom, Eric Doran, Elizabeth Head, Ira T. Lott, Frederick A. Schmitt

Neurology Faculty Publications

Primary care integration of Down syndrome (DS)-specific dementia screening is strongly advised. The current study employed principal components analysis (PCA) and classification and regression tree (CART) analyses to identify an abbreviated battery for dementia classification. Scale- and subscale-level scores from 141 participants (no dementia n = 68; probable Alzheimer’s disease n = 73), for the Severe Impairment Battery (SIB), Dementia Scale for People with Learning Disabilities (DLD), and Vineland Adaptive Behavior Scales—Second Edition (Vineland-II) were analyzed. Two principle components (PC1, PC2) were identified with the odds of a probable dementia diagnosis increasing 2.54 times per PC1 unit increase and by …

Impact Of Nitrogen Rate In Conventional And Organic Production Systems On Yield And Bread Baking Quality Of Soft Red Winter Wheat, Ammar Al-Zubade, Timothy D. Phillips, Mark A. Williams, Krista L. Jacobsen, David Van Sanford

Plant and Soil Sciences Faculty Publications

Soft red winter wheat (SRW) is characterized by high yield and relatively low protein content. In Kentucky, there is growing demand from local artisan bread bakers for regionally produced flour, requiring production of grain with increased protein content and/or strength. The objective of this two-year field experiment was to evaluate the effect of nitrogen (N) management on five cultivars of winter wheat on yield and bread baking quality traits of modern and landrace SRW cultivars (Triticum aestivum L.). All five cultivars were evaluated using two N application rates in conventional and organic production systems. All traits measured were significantly …

Tropical Legumes To Augment Forage Yield In The Eastern Caribbean, E. Valencia, M. B. Adjei

IGC Proceedings (1977-2023)

Little information is available on the contribution of tropical legumes to forage yield in the eastern Caribbean. This study assessed the effects of three grazing cycles (GC; 5, 10 and 15-wk) on seasonal dry matter (DM) yield of binary mixtures of the tropical legumes glycine (Neonotonia wightii) and desmanthus (Desmanthus virgatus) with “Bambatsi” (Panicum coloratum) and “Mottgrass” (Pennisetum purpureum Shum.). Plant responses were assessed by mob-grazing with sheep (12-24 hrs; to average stubble height of 15-cm) for each GC. Grazing cycles affected yield of both the legume and grass component (P< 0.05). At GC of 5-weeks, forage DM ranged from 1.5-2.0 Mg ha^-1 in …

Yield And Forage Quality In Alfalfa-Weeping Lovegrass Mixtures, H. Laborde, R. E. Brevedan, M. A. Varillas, M. N. Fioretti

IGC Proceedings (1977-2023)

Little is known about the relative performance of weeping lovegrass in mixtures with alfalfa. Our objective was to compare the productivity and forage quality of monocultures and binary mixtures of the species. Mixtures always gave higher yields than any of the monocultures and the highest was obtained in the mixture with the largest proportion of alfalfa. In the second year weeping lovegrass N concentration in the mixtures were higher than in monoculture. Weeping lovegrass did not affect the alfalfa N concentration. There was not differences in the NDF, for between these species.