Physical Sciences and Mathematics Commons^™

Characterizing Feeds And Feed Availability In Sud-Kivu Province, Dr Congo, Samy B. Bacigale, Birthe K. Paul, Fabrice L. Muhimuzi, Neville Mapenzi, Michael Peters, Brigitte L. Maass

IGC Proceedings (1993-2023)

Animal husbandry in the Sud-Kivu province of the Democratic Republic of the Congo (DRC) is gradually moving towards stall feeding, due to demographic pressure (Battistin et al. 2009) and scarcity of collectable forages (DSRP-RDC 2005). Therefore, feed is considered one of the main constraints faced by livestock production, especially in the dry season (Katunga et al. 2009; Maass et al. 2012). Unaffordable, fluctuating prices and inaccessibility of feed concentrates and the lack of improved forages adapted to marginal conditions, making them non-competitive with food crops, further exacerbate the livestock feeding situation. This study within the African Food …

Features Of The Physical Properties Of The Modified Surface Of The P-Cdte – Znse Film Heterostructure With Deep Impurity Levels, Yuozas Y. Vaytkus, Nodir E. Alimov, Salim M. Otajonov

Scientific Bulletin. Physical and Mathematical Research

This article analyzes the spectrum of the photocurrent in a layered film heterostructure CdTe-ZnSe with deep primesnymi levels. The experimental results demonstrated that the heterostructure CdTe-ZnSe observed a new effect in the measurement of the photoconductivity spectra, depending on the direction of the applied electric field, and the applied field stimulates the emergence of photo-emf. The spectrum of the photocurrent in a layered CdTe- ZnSe heterostructure film with deep impurity levels are considered in the article. It follows from the experimental results that a new effect is observed in the CdTe-ZnSe heterostructure when measuring the photoconductivity spectra depending on the …

Definition Of Extended Structural Defects In Epitaxial Films Of Znteg‘Gaas Grown By Mbe, Muratbay B. Sharibaev, Kanatbay A. Ismailov, Ibrohim N. Karimov, Murodjon Z. Nosirov

Scientific Bulletin. Physical and Mathematical Research

The last three decades of the development of solid state physics are characterized by the fact that the main objects of research are increasingly not massive crystals, but thin films, multilayer thin-film systems, conducting filaments and crystallites of small size. Epitaxial films are grown on a substrate of a single crystal of the same or another material. In the first case, the epitaxial layer with the correct technology becomes a natural extension of the substrate. Epitaxial film can be doped with various impurities. To introduce an alloying admixture into the epitaxial film, three methods are used. According to the first …

Spectral Characteristics Of The Absorption Coefficient And Energy Position Of Defects, Sirojiddin Z. Zaynobidinov, Rustamjon G. Ikramov, Mashhurahon A. Nuriddinova, Khurshid A. Muminov

Scientific Bulletin. Physical and Mathematical Research

In this paper, a theoretical method to study the spectral characteristics of the absorption coefficient, namely the area of ​​defective absorption of amorphous hydrogenated silicon according to the Davis-Mott approximation from the Kubo-Greenwood formula. It is shown that using the experimental spectral characteristic of the defect absorption coefficient, one can determine the energy position of defects in the mobility gap. Optical transitions of electrons, in which electronic states participate in defects, indicate that there are three types of optical transitions of electrons: between defects, between defects and tails of allowed zones, and also between defects and allowed zones. It was …

Sub-Barrier And Above-Barrier Electron Transport Through Multilayer Semiconductors, Vohob R. Rasulov, Rustam Y. Rasulov, Ikbol M. Eshboltaev, Ravshan R. Sultonov

Scientific Bulletin. Physical and Mathematical Research

In the article the transparency coefficients of the semiconductor structure, consisting of alternating asymmetric potential barriers and wells, where the Bastard condition is taken into account, are calculated. It is shown that in the structure there should be an oscillation of the transmission coefficient of electrons depending on their energy, which is due to the interference of the de Broglie waves reaching the barrier and reflected from the potential barrier. The electronic states of a multilayer semiconductor structure consisting of alternating potential wells and barriers are analyzed. It has been shown that both in the above-barrier and in the barrier …

Scientific Foundation Of The Rate Of Falling Of Raw Materials On Walnut Breakage Device, Otabek A. Mirzaev, Xolhuzha A. Sobirov, Nusratillo R. Barakaev

Scientific Bulletin. Physical and Mathematical Research

Today, there are many types of fruits that are separated the kernel from the shell: walnuts, almonds, filberts, chestnuts, pistachios and cashews. Nuts have a high calorific value and a rich nutrient composition. The most critical and delicate operation is shell cracking to extract the fragile whole kernel from the shell. Studies on nut rupturing are particularly focused on the following three aspects: the physical characteristics of nuts, the mechanical properties of nut rupturing, and nut rupturing equipment. Determining the velocity of the nut entered into the apparatus will allow the machine to operate normally, but will also increase its …

Eigenvalue Problems For An Elliptic Equation With Two Singular Coefficients, Asror M. Shokirov

Scientific Bulletin. Physical and Mathematical Research

For the elliptic type of differential equation with two singular coefficients, the quadratic values of the Dirixle and Dirixle-Neumann problems were found in the quarter in that work. The field and boundary conditions for solving these problems are described in the polar coordinate system. The result is a rectangle in the polar coordinate system. Then, we used the method of separating variables in the right rectangle, that is, divided the variables by the equation and divided the problem into two distinct values for ordinary differential equations. The first of the ordinary differential equations is the substitution of , where the …

Studies Of Tribotechnical Properties Of Composite Polymeric Materials Of Machine Designation, Tojiboy O. Almataev, Nozimbek T. Almataev

Scientific Bulletin. Physical and Mathematical Research

In the given work are experimentally investigated tribotechnical properties as intensity of wear process and factor of a friction composite epoxy the polymeric materials processed by ultrasound. Results of influence of a kind and the maintenance loading on tribotechnical properties composite epoxy polymeric materials depending on modes of ultrasonic processing are received. Correlation dependence of intensity of wear process and factor of a friction composite epoxy coverings from modes of ultrasonic processing is established. It is shown in the work that with an increase in the duration of ultrasonic exposure, the wear rate and the friction coefficient of the coatings …

The Task Of Prosecuting Simple Differential Games On The Rectangle, Azizhon O. Zunnunov

Scientific Bulletin. Physical and Mathematical Research

The theory of differential games is developed and resulted from modeling technical problems. Some of the problems in differential games theory can be described as controlling two moving objects, i.e. one of them is the follower that tries to catch the other object, and obviously the other object is the runner. The runner tries to run away from the follower. Most of the practical and theoretical IT problems, planning, technical and other challenges will be derived to the differential games theory for resolution. Thus researching this theory is one of most important topics currently. A lot of researchers contributed enormous …

Structure And Electro Physical Properties Of Solid Solution (Si2)1-X(Cds)X (0 £ X £ 0.01), Xurshidjon M. Madaminov

Scientific Bulletin. Physical and Mathematical Research

This paper shows the possibility of obtaining a single-crystal solid solution for the substitution of p-Si-n-(Si2)1-x (CdS)x (0 £ x £ 0.01) on silicon substrates with a diameter of 20 mm and thickness » 400, with a crystallographic orientation (111) n-types of conductivity with a specific resistance of 1 Ω cm, by the method of liquid phase epitaxy from Sn – Si – CdS solution – melt in a hydrogen atmosphere purified by palladium. Perfect epitaxial layers with mirror surfaces and with the best parameters are grown under the following technological conditions: temperatures start crystallization –1150 ОС, speed of forced …

Modeling It Of Discourse Analysis And The Ussues Machine Translation, Nilufar Z. Abdurakhmonova, Allayorzhon G. Teshabayev

Scientific Bulletin. Physical and Mathematical Research

The aim of the research work is to analyze theories on the formation of linguistic database of the translation program of simple texts from English into Uzbek and to create program foundations. The object of the research work is word combinations and simple sentences of English and Uzbek languages, grammatical expressions as well. Scientific novelty of the research work is as follows: Drawn conclusions provide exactness of translation on creating linguistic database of machine translation. created linguistic database of phrasal verbs, morphological lexicon, affixes of English and Uzbek languages and their morphological and syntactic models; identified coordination of simple sentence …

Description Of 2-Local Two Sided Multiplication On An Algebra Of Matrices, Farhodjon N. Arzikulov, Kamola A. Solijanova

Scientific Bulletin. Physical and Mathematical Research

The present paper is devoted to 2-local derivation on associative and Jordan matrix rings. In 1997, P. Semrl introduced the notion of 2-local derivations and described 2-local derivations on the algebra ¬B(H) of all bounded linear operators on the infinite-dimensional separable Hilbert space H. A similar description for the finite-dimensional case appeared later in 2004. In the paper Y. Lin and T. Wong 2-local derivations have been described on matrix algebras over finite dimensional division rings. In 2012 Sh. Ayupov, K. Kudaybergenov suggested a new technique and have generalized the above mentioned results for abritrary Hilbert spaces. Namely they considered …

Application Of Optoelectron Converters Of Reflective Type For Automation Of Liquid And Gas Version Test Measuring Units, Yuriy G. Shipulin, Otabek T. Almataev

Scientific Bulletin. Physical and Mathematical Research

This work is devoted to the use of reflective optoelectronic converters for the automation of liquid and gas calibration flowmeter installations. Liquid and gas calibration flowmeter devices are widely used for verification and certification of various liquid and gas flowmeters and meters. The analysis of the principles of construction of a reflective optoelectronic converter for calibration devices is carried out and the basic principles of their construction are determined. A functional diagram of an experimental automated programmable calibration test setup of flow meters, liquid meters developed on the basis of ROC is presented. High accuracy requirements are imposed on the …

Investigation Of Membrane Protein Dynamics Using Correlative Single-Particle Tracking And Super-Resolution Microscopy Combined With Bayesian Inference Of Diusion In Arbitrary Landscapes, Hanieh Mazloom Farsibaf

Physics & Astronomy ETDs

Many experiments have shown that the diffusive motion of lipids and membrane proteins are slower on the cell surface than those in artificial lipid bilayers or blebs. One hypothesis that may partially explain this mystery is the effect of the cytoskeleton structures on the protein dynamics. To test this hypothesis, we designed a high-speed single particle tracking microscope and use a hybrid tracking and super-resolution approach on the same cell. We labeled the high-affinity FceRI receptor as a transmembrane protein and GPI-anchored proteins as an example of outer leaflet protein in Rat Basophilic Leukemia (RBL) cells and tracked these membrane …

Ueb Parallel: Distributed Snow Accumulation And Melt Modeling Using Parallel Computing, Tseganeh Z. Gichamo, David G. Tarboton

Publications

The Utah Energy Balance (UEB) model supports gridded simulation of snow processes over a watershed. To enhance computational efficiency, we developed two parallel versions of the model, one using the Message Passing Interface (MPI) and the other using NVIDIA's CUDA code on Graphics Processing Unit (GPU). Evaluation of the speed-up and efficiency of the MPI version shows that the effect of input/output (IO) operations on the parallel model performance increases as the number of processor cores increases. As a result, although the computation kernel scales well with the number of cores, the efficiency of the parallel code as a whole …

Domain-Wall Tunneling Electroresistance Effect, M. Li, L. L. Tao, Evgeny Y. Tsymbal

Department of Physics and Astronomy: Faculty Publications

Ferroelectric tunnel junctions (FTJs) utilizing an in-plane head-to-head ferroelectric domain wall (DW) have recently been realized, showing interesting physics and new functionalities. However, the DW state in these junctions was found to be metastable and not reversible after applying an electric field. In this work, we demonstrate that a stable and reversible head-to-head DW state can be achieved in FTJs by proper engineering of polar interfaces. Using density functional theory (DFT) calculations and phenomenological modeling, we explore the DW stability by varying stoichiometry of the La_1−xSr_xO=TiO₂ interfaces in FTJs with La_0.5Sr_{0.5 …}

Social Ecological Factors Affecting Substance Abuse In Ghana (West Africa) Using Photovoice, Ahmed Kabore, Evans Afriyie-Gyawu, James Awuah, Andrew R. Hansen, Ashley Walker, Melissa Hester, Moussa Aziz Wonadé Sié, Dhruv Medarametla, Nicolas Meda

Department of Biostatistics, Epidemiology, and Environmental Health Sciences Faculty Publications

Introduction: substance abuse is an important public health issue affecting West Africa; however, there is currently a dearth of literature on the actions needed to address it. The aim of this study was to assess the risks and protective factors of substance abuse in Ghana, West Africa, using the photovoice method.

Methods: this study recruited and trained 10 participants in recovery from substance abuse and undergoing treatment in the greater Accra region of Ghana on the photovoice methodology. Each participant received a disposable camera to take pictures that represented the risk and protective factors pertinent to substance abuse …

The Effect Of Leucaena Leucocephala On Beef Production And Toxicity In The Chaco Region Of Argentina, Alejandro Radrizzani, José A. Nasca

IGC Proceedings (1993-2023)

Hedgerows of the fodder tree legume, Leucaena leucocephala (Lam.) de Wit ssp. glabrata (Rose Zárate) (leucaena), planted with companion grass, provide productive, profitable and sustainable tropical pasture (Shelton and Dalzell 2007). Although leucaena can improve beef production from tropical pastures, poor grower adoption has limited development of leucaena in the Chaco Region of Argentina. This can be partly attributed to: (1) unsuccessful establishment; (2) limited understanding of leucaena management as a forage resource; and (3) concerns about mimosine toxicity. These 3 limitations have been overcome in other regions of the world (e.g. northern Australia and the Chaco Region of …

Establishment And Growth Of Legumes On Uncultivatable Hill Country In East Coast New Zealand, Trevor L. Knight, Tom J. Fraser, Paul D. Muir, Chikako Van Koten

IGC Proceedings (1993-2023)

Steep, non-arable hill country is a significant feature of New Zealand farming (Sheath 2011) and large tracts of it have been improved by over-sowing grass and assorted clover species, particularly white clover (Trifolium repens L.). Numerous other legume species are available in New Zealand from similar environments overseas that may be more productive on some steep hill country. Plant breeders in New Zealand have also produced inter-specific hybrids (Williams et al. 2010) with potentially useful attributes. As part of a large project to increase pasture production on non-arable hills, a range of legume species were established at 2 …

Evaluation Of Limpograss (Hemarthria Altissima) Breeding Lines Under Different Grazing Managements, Marcelo O. Wallau, Lynn E. Sollenberger, Kenneth H. Quesenberry, João M. B. Vendramini, M. K. Mullenix

IGC Proceedings (1993-2023)

Limpograss (Hemarthria altissima (Poir.) Stapf et C.E. Hubb.) is a stoloniferous, warm-season perennial grass from South Africa. It is frequently used to extend the grazing season in poorly drained soils of subtropical regions (Quesenberry et al. 2004). The cold tolerance of limpograss allows it to grow at temperatures below which other commonly used warm-season grasses (e.g. bermudagrass) remain productive. Use of limpograss has helped to reduce forage shortfall during winter, therefore, reducing feeding costs. In the past 30 years, the area planted to limpograss in Florida, USA has grown faster than that of any other forage grass species. …

Vertical Distribution Of Leaves And Stems On The Sward And Forage Intake By Lambs In Tifton-85 Pasture, Alda L. G. Monteiro, Cláudio J. A. Da Silva, Marina G. B. Da Silva, Sergio R. Fernandes, César H. E. C. Poli, Nelson T. Santos Jr., Thiago Augusto Cruz, Carolina Dalagassa Dos Santos

IGC Proceedings (1993-2023)

Sward characteristics affect the performance of grazing livestock, especially for the youngest animals. The aim of this study was to evaluate the relationship between the vertical distribution of leaves and stems on the sward and the forage intake parameters of lambs in four sheep meat production systems grazing a Bermudagrass (Cynodon dactylon) cv. Tifton-85 pasture.

Adaptability And Stability Of Productive Characteristics On The Selection Of Pennisetum Purpureum Schum. Clones Grazed By Sheep, Alexandre C. L. De Mello, Bruno L. Viana, Mário De A. Lira, Adriana Guim, José C. B. Dubeux Jr., Mércia V. F. Dos Santos, Márcio V. Da Cunha, Sílvio H. Lino Dias

IGC Proceedings (1993-2023)

Elephant grass (Pennisetum purpureum Schum.) is one of the most widely used forages in Brazil, due to its high potential productivity, forage quality, palatability, vigour and persistence. Dwarf types of elephant grass are the object of selection programs for their higher leaf/stem ratio and lower grazing height, resulting in more efficient pasture management. They have high potential for ruminant production (Almeida et al. 2000), but have markedly different morphological and productive characteristics (Cunha et al. 2011) to tall varieties of the same species.

Adaptability and stability analyses are selection tools which allow identification of plant responses to …

Recent Development Of Pasture Plants In Queensland, Kendrick G. Cox

IGC Proceedings (1993-2023)

No abstract provided.

Legumes--A High Quality Protein Source In Latvian Animal Feeds, Baiba Osmane, Imants Jansons, Aleksandrs Jemeljanovs, Sallija Cerina, Liga Proskina

IGC Proceedings (1993-2023)

Farms in Latvia have an insufficient amount of protein in a feed for herbivorous animals. To tackle this issue, plants containing high protein content should be cultivated in grass mixtures. Legumes are rich in protein and play an important role on farms with dairy livestock. It is advisable to have at least 30-50% of legumes in mixtures with grass for grazing animals and to conserve fodder for the winter period, which lasts from November to May. As well as being rich in protein, legumes have a high dry matter digestibility (TDN) and high energy content (NEL). While legumes during the …

Approaches Toward Sustainable Forage-Livestock Systems: Strip-Planting A Legume Into A Warm-Season Perennial Grass Pasture, Miguel S. Castillo, Lynn E. Sollenberger, Ann R. Blount, Jason A. Ferrell, Mary J. Williams, Cheryl L. Mackowiak

IGC Proceedings (1993-2023)

Despite the demonstrated potential of rhizoma peanut (Arachis glabrata Benth.; RP) for grazing in the southeastern USA (Ortega-S. et al. 1992), high establishment cost and removal of land from production during establishment have limited its use to primarily hay production systems. The premise of this experiment is that strip-planting RP in existing bahiagrass (Paspalum notatum Flügge) pastures offers the opportunity to use grass forage during the legume establishment phase so that land need not be totally removed from grazing, while allowing successful establishment of the legume.

Meat And Milk Production On Irrigated Birdsfoot Trefoil Pastures In The Mountain West Usa, Jennifer W. Macadam, Sara R. Hunt, Silvana Martini, Rachael Christensen, Jong-Su Eun

IGC Proceedings (1993-2023)

Irrigated birdsfoot trefoil (BFT; Lotus corniculatus L.) is a productive, persistent perennial legume in the Mountain West region of the United States of America (USA) (MacAdam and Griggs 2006). It does not cause bloat, even when grazed in pure stands, because it contains a relatively small amount (2-4% of dry matter (DM)) of condensed tannins (Mueller-Harvey 2006; Waghorn 2008). Birdsfoot trefoil tannins bind excess plant proteins at rumen pH (~ pH 6.2) sufficiently to prevent bloat and then release these proteins into the abomasum at gastric pH (~ pH 2.5). This allows plant proteins to be digested to amino acids …

Native Shrubs For Grazing In The Dry, Semi-Arid Sand Dunes Of The Mallee Region Of Victoria, Australia, Dave Monks

IGC Proceedings (1993-2023)

Native shrubs have potential for growth and grazing in dry areas where alternative perennial pasture options are limited. Deep-rooted perennials have also been shown to reduce groundwater recharge and salinity to improve ecological stability. A forage shrub evaluation experiment was established at the Walpeup Research Station in the Mallee region of Victoria, Australia to compare the performance of a range of native species. The work was conducted as part of the Enrich project with the Future Farm Industries Cooperative Research Centre.

Influence Of Grazing Exclusion On Vegetation And Productivity Of Kyrgyz Pastures, N. V. Kilyazova, М. I. Аdenov, К. A. Samsaliev, А. Каrybekov, B. Jeangros

IGC Proceedings (1993-2023)

The aim of this study was to assess the effect of grazing exclusion on the vegetation and productivity of: (1) pastures near villages that are grazed intensively through-out the year; and (2) pastures, which are used in summer and are less intensively grazed through the remainder of the year. The potential of degraded pastures to recover, when protected from overgrazing, was also evaluated. Six pastures (3 located in or near villages and 3 used for summer grazing) were selected with local community representatives in 3 pilot regions of Kyrgyzstan (the Lahol and Теrеk regions of Naryn oblast and the Оrgochor …

Establishment Techniques To Increase The Production Of Italian Ryegrass (Lolium Multiflorum) Over-Sown Into An Irrigated Kikuyu (Pennisetum Clandestinum) Pasture, Joseph C. Fitzgerald, Mark N. Callow

IGC Proceedings (1993-2023)

Irrigated mixed pastures of kikuyu (Pennisetum clandestinum) over-sown with Italian ryegrass (Lolium multiflorum) in the cool-season (May-October) can produce large amounts of biomass in a sub-tropical environment (Botha et al. 2008). However, appropriate pasture management practices are required to suppress the aggressive growth of kikuyu prior to autumn, in order to facilitate establishment of ryegrass seedlings.

The present study evaluated ryegrass establishment techniques on the dry matter (DM) production, botanical composition and forage quality of a mixed sward containing kikuyu.

Management Strategies To Increase Festulolium Productivity And Persistence, Gerónimo Cardozo, Walter Ayala, Ethel Barrios

IGC Proceedings (1993-2023)

A biennial hybrid of Lolium multiflorum x Festuca pratensis (Festulolium INIA Merlin) was released by the National Institute of Agricultural Research of Uruguay (INIA) in 2008. INIA Merlin is a tetraploid cultivar with a long growing season, semi-prostrate habit and high herbage quality (García 2003). These characteristics make it potentially useful to include Festulolium in short and intensive pasture-crop rotation systems. Grazing management can be used to modify growth, sward structure and persistence, and is known to be critical during the second year of production for stability and sustainability of farming systems that include this type of species. The objective …