Physical Sciences and Mathematics Commons^™

Implications Of Land Use Changes On The Yields In Dry Matter, Energy And Protein Of Range And Crop Fields In Zamfara Reserve, Northwestern Nigeria, B. S. Malami, P. H. Y. Hiernaux, H. M. Tukur, B. Rischkowsky

IGC Proceedings (1993-2023)

The Zamfara reserve is a 235,500 ha grazing land within the Sudan savannah zone (12º 10' - 13º 05 N; 6º 30' - 7º15' E) of north western Nigeria. Rainfall varies from 500mm in the north to 800mm in the south of the reserve, and is restricted within the months of May - September. The reserve is an important grazing site for the herds of sedentary, transhumant and agro pastoralists. Population growth within the farming communities in the reserve has led to the conversion of more grazing land to croplands. This work was carried out to evaluate the quantity and …

Effect Of Dairy Effluent On Turnip Yields, Joe L. Jacobs, G. N. Ward, Frank R. Mckenzie

IGC Proceedings (1993-2023)

Dairy effluent is a significant point source in the pollution of waterways. Only 50% of dairy farms in the dryland regions of Victoria, Australia, have suitable dairy effluent systems of which only 25% are managed effectively (IRIS Research 2000). Despite many farmers viewing effluent as an undesirable waste, it contains relatively large amounts of agronomically valuable nutrients especially nitrogen (N) and potassium (K). Results are reported from the first two years of a three year study comparing turnip leaf and root dry matter (DM) responses to a range of dairy effluent rates.

Nitrogen Use Efficiency Of Specialized Dairy Farms In Flanders: Evolution And Future Goals, Frank Nevens, I. Verbruggen, M. Meul, D. Reheul

IGC Proceedings (1993-2023)

Efficient use of nutrients is one of the major aims of eco-efficient and sustainable agricultural production systems. We determined the nitrogen use efficiency of a representative set of specialised dairy farms in Flanders, between 1989-1990 and 2000-2001 and set achievable eco-efficiency targets for sustainability.

Production Systems To Integrate Livestock Grazing And Grain Production In Southern Brazil And Midwestern Usa, R. Mark Sulc, A. Moraes, S. J. Alves, A. Pelissari, Paulo C. De F. Carvalho, C. R. Lang

IGC Proceedings (1993-2023)

Agriculture in the USA and Brazil has undergone similar and dramatic changes in the past 20 years. In both countries, production systems have become increasingly specialized. Large farms are characterized by single enterprises, simple crop rotations, and livestock production is segregated from grain production. The lack of diversification and high production costs expose producers to risk from economic swings of single enterprises and greater reliance on pesticides and synthetic fertilizers to maintain profitability, along with greater risk of soil erosion from continuous row crop production. Scientists in southern Brazil and Ohio are collaborating to develop no-tillage systems that integrate livestock …

Seed Size And Its Relationship With Crop Establishment, Productivity And Nutritive Value In Genotypes Of Maize For Silage, C. Pérez, M. R. Tovar G., G. García, A. Carballo, G. Mendoza, T. Vásquez, F. González, M. Crosby

IGC Proceedings (1993-2023)

For a high dry matter (DM) yield of forage maize an adequate population of plants is required, which is related to germination, vigour, and seed size (Ellis, 1992). The objective of the present study was to investigate seed size and its relationship to establishment, productive and nutritional potential of silage maize, which has not before been reported in the literature.

Random Variables With Overlapping Number And Weyl Algebras Ii, Ruma Dutta, Gabriela Popa, Aurel Stan

Journal of Stochastic Analysis

No abstract provided.

Comparison Of Technologic And Economic Parameters Of Drills For Grassland Oversowing, Lubomir Gonda, M. Kunský

IGC Proceedings (1993-2023)

Direct grassland oversowing is a very important technology in Slovakia as some 350,000 ha (42 %) of grassland are on unploughable sites that dominate mountain regions. Slope inclinations > 16° and shallow soil layers (150-200mm) limits ploughing on these sites (Tiley & Frame, 1988).

Repeated Strip-Seeding Of A Legume-Grass Mixture Into Permanent Grassland In The Czech Republic, A. Kohoutek, P. Komárek, V. Odstrčilová, P. Nerušil

IGC Proceedings (1993-2023)

Although ruminants do not belong to the main consumers of protein supplements, there is a possibility to decrease the use of feed grain by increasing the protein content in the forage from permanent grassland. This paper describes strip-sowing of a legume-grass mixture. Saved protein supplements can then be used for feeding pigs and poultry.

Strip-Seeding Of Red Clover, Lucerne, Alsike Clover, White Clover And Sainfoin Into Grassland In Central Europe, P. Komárek, A. Kohoutek, V. Odstrčilová, P. Nerušil

IGC Proceedings (1993-2023)

Strip-seeding of legumes into grassland improves forage quality and adds fixed nitrogen (N) to grassland, which decreases the need for mineral N.

Persistence Of Timothy In Mixture With Smooth Meadow Grass, H. Björnsson

IGC Proceedings (1993-2023)

Timothy (Phleum pratense) is the most common grass species in Iceland for the production of high quality herbage for dairy cows. For this purpose timothy is cut early, often around heading. The high quality, however, is at the cost of limited persistence of timothy. If cut late, three to four weeks after heading, timothy cultivars of northern origin can sometimes dominate for a long time, especially if the aftermath is not cut or grazed. Earlier experiments have shown that, relative to a late cutting treatment, the percentage timothy in the first harvest is reduced by one unit for …

Improvement Of Lucerne Cutting Management: The Relative Impact Of Initial Organic Reserves, Cutting Height And Residual Leaf Area On Forage Yield, J. C. Avice, F. Meuriot, M. L. Decau, A. Morvan-Bertrand, M. P. Prud'homme, F. Gastal, J-C. Simon, J. J. Volenec, A. Ourry

IGC Proceedings (1993-2023)

Less lucerne (Medicago sativa L.) is now grown because of difficulties arising from 2 interacting characteristics: productivity and stand persistence. Optimisation of these two parameters depends highly of the cutting management (cutting height and/or frequency) and of the taproot N reserves. For example, Avice et al. (1997) showed that lucerne shoot regrowth is relates closely to taproot soluble protein concentrations (especially vegetative storage protein: VSP). However, it is not known how stubble C-N reserves and/or residual leaf area (both depending of the cutting management) influence the contribution of taproot reserve-derived C-N supply to regrowing lucerne shoots after defoliation. …

The Effect Of Sowing Date And Autumn Management On Sainfoin (Onobrychis Viciifolia) Regrowth And Yield, Z. G. (Zhigang) Liu, G. P. F. Lane

IGC Proceedings (1993-2023)

Due to its characteristics (palatability, non-bloating, high protein, high voluntary intake etc.: Frame, 1998), sainfoin was a traditional forage legume in the UK, grown widely during the 17-19th century (Bland, 1971). It has almost disappeared in recent years. The rise of organic farming and the need for home-grown protein may encourage the return of sainfoin. This experiment aimed to explore the impact of sowing date and autumn management on the growth and yield of sainfoin in UK.

Rangelands In The Mediterranean Zone Of Croatia, J. Rogosic

IGC Proceedings (1993-2023)

Rangelands dominate the landscape of the Mediterranean part of Croatia along the Adriatic coastline, occupying 83% of the agricultural land (1.7 million ha) and 40% of the entire country. The proportion of rangelands is considerably higher in the Mediterranean littoral than in other ecological regions of Croatia. Sheep and goats are widespread in the region, comprising 76% of total sheep and goat numbers in Croatia. However, in comparison to other regions of Croatia, livestock production in the Mediterranean zone is not well developed. Continuous grazing begun too early in the growing season has caused substantial rangeland degradation and a decline …

Plant Arrangement Effects On Dry Matter Production And Nitrogen Fixation Of Berseem Clover: Annual Ryegrass Mixture, C. Attardo, G. Di Miceli, A. S. Frenda, D. Giambalvo, C. Scarpello

IGC Proceedings (1993-2023)

Agronomic factors affect the productivity and efficiency of cereal-legume intercropping systems (Ofori & Stern, 1987). This research aimed to determine the effects of different plant arrangement on hay yield, nitrogen (N) content and N fixation of berseem clover-annual ryegrass mixture in a Mediterranean semi-arid environment.

Long-Term (9-Year) Response Of Two Semiarid Grasslands To Prescribed Fire In The Southwestern Usa, R. L. Pendleton, B. K. Pendleton, C. S. White

IGC Proceedings (1993-2023)

Historically, arid grasslands of SW USA experienced fire return intervals of 5-10 years. During the last 100 years, however, fire has been a rare event. Recent expansion of woody plants in arid grasslands has prompted managers to re-introduce fire as a tool to reduce abundance of woody plants and maintain perennial grass cover. The use of fire in desert grasslands poses unique challenges, however, due to extreme variability in rainfall patterns. Our research examines vegetation response to repeat fire in 2 desert grassland ecotones near Albuquerque, New Mexico (35.05^o N 106.60^o W).

Studies On Rehabilitation And Recovery Of Degraded Shrub Rangeland In Central China, G. Xiao

IGC Proceedings (1993-2023)

Central China used to be the most important region for animal production, but over-grazing, over- cultivation and deforestation all resulted in a decline in shrub rangeland productivity as well as increasing soil degradation (JiZhou, 1989). Soil erosion, salinisation and desertification have become serious problems. The productivity of shrub rangeland decreased from 3,000~4,000kg/ha to 1,500~2,000kg/ha from the 1960s to the 1990s (Wei, 1991). Since 1990, measures have been taken to solve this problem with promising results.

Reasons For The Premature Decline In Astragalus Adsurgens Stands In Kerqin Sandy Land, Qizhong Sun, Z. L. Wang, J. G. Han, Y. W. Wang, G. R. Liu

IGC Proceedings (1993-2023)

Diseases partly account for reductions in Astragalus adsurgens stand longevity. The effect of some cultural practices on the control of pests and diseases have been reported (Hou, 1986; Nan, 1996), but few reports have detailed the relationship among soil fertiliser status, diseases and premature stand decline. This study was conducted to investigate these relationships in order to extend the longevity of Astragalus adsurgens stands.

Improvement Of The Mediterranean Agro-Silvopastoral System Montado, J. Potes, H. Babo, D. Navas

IGC Proceedings (1993-2023)

"Montado" is an old man-made agro-silvopastoral system, with three vegetation components (trees, shrubs and herbs) used for multiple species animal husbandry in extensive production systems (Potes & Babo, 2003). Several authors have reported on the improvement of Mediterranean annual self-reseeding pastures (Espejo-Diaz, 1996) and increased stocking rates.

On Image Response Regression With High-Dimensional Data, Noah Fuerth

Major Papers

A recent issue in statistical analysis is modelling data when the effect variable

changes at different locations. This can be difficult to accomplish when the dimensions

of the covariates are very high, and when the domain of the varying coefficient

functions of predictors are not necessarily regular. This research paper will investigate

a method to overcome these challenges by approximating the varying coefficient

functions using bivariate splines. We do this by splitting the domain of the varying

coefficient functions into a number of triangles, and build the bivariate spline functions

based on this triangulation. This major paper will outline detailed …

On Maximum Likelihood Estimators For A Jump-Type Affine Diffusion Two-Factor Model, Jiaming Yin Mr.

Major Papers

We consider a jump-type two-factor affine diffusion model driven by a subordinator in the context of continuous time observations. We study the asymptotic properties of the maximum likelihood estimator (MLE) for the drift parameters. In particular, we prove the strong consistency and the asymptotic normality of MLE in the subcritical case. We also present some numerical illustrations to confirm the theoretical results. The main difficulty of this major paper consists in proving the ergodicity of the model in the subcritical case and deriving the limiting behavior of the process.

Tiller Dynamic Of Guineagrass (Panicum Maximum) Under Defoliation, T. Clavero, R. Razz

IGC Proceedings (1993-2023)

Guineagrass (Panicum maximum) is a perennial warm season bunchgrass native to Africa that has been introduced to many tropical areas. Its management is important because of its important role in animal production. Total production of herbage and the persistence of tufted grasses can be markedly reduced when the grass is defoliated too frequently and too intensively (Clavero, 1997). In order to determine the proper management for optimum production and long term persistence, it is important to study the effect of cutting practices on tiller dynamics of guineagrass.

Raw Diffraction Data For 3tel-Hlx-Darpin (Sumo), Wwpdb Id: 7n2b, Supeshala D. Nawarathnage, Parag Laljibhai Gajjar, Derick R. Bunn, Cameron Stewart, Tzanko I. Doukov, James Moody

ScholarsArchive Data

This X-ray diffraction dataset was collected on October 21Oct2020 at SSRL Beamline BL9-2. The crystal was of 3TEL-hlx-DARPin (SUMO) The solved structure used frames 1-1799 and has been deposited in the wwPDB under the PDB ID 7N2B. This data can be readily processed using XDS, AutoProc, CCP4, HKL2000/3000, or other crystallographic X-ray diffraction data processing software. The files have a human-readable header but are otherwise binary.

Single-Mode Quasi Pt-Symmetric Laser With High Power Emission, Enes Şeker, Babak Olyaeefar, Khalil Dadashi, Serdar Şengül, Mohammad Hosain Teimourpour, Ramy El-Ganainy, Abdullah Demir

Michigan Tech Publications

Large-area lasers are practical for generating high output powers. However, this often comes at the expense of lower beam quality due to the introduction of higher-order modes. Here, we experimentally demonstrate a new type of electrically pumped, large-area edge-emitting lasers that exhibit a high power emission (∼ 0.4 W) and a high-quality beam (M ∼ 1.25). These favorable operational characteristics are enabled by establishing a quasi PT-symmetry between the second-order mode of a large area two-mode laser cavity and that of a single-mode auxiliary partner cavity, i.e., by implementing a partial isospectrality between the two coupled cavities. This in turn …

Raw Diffraction Data For 1tel-Aa-Vwa (Sumo), Wwpdb Id: 7n1o, Moriah H. Mathis, Braydan D. Bezzant, Diana T. Ramírez, Supeshala D. Nawarathnage, Tzanko I. Doukov, James Moody

ScholarsArchive Data

This X-ray diffraction dataset was collected on October 21Oct2020 at SSRL Beamline BL9-2. The crystal was of Batch 1 1TEL-AA-vWa (SUMO) The solved structure used frames 1-999 and has been deposited in the wwPDB under the PDB ID 7N1O. This data can be readily processed using XDS, AutoProc, CCP4, HKL2000/3000, or other crystallographic X-ray diffraction data processing software. The files have a human-readable header but are otherwise binary.

Grm: Generative Relevance Modeling Using Relevance-Aware Sample Estimation For Document Retrieval, Iain Mackie, Ivan Sekulic, Shubham Chatterjee, Jeffrey Dalton, Fabio Crestani

Computer Science Faculty Research & Creative Works

Recent studies show that Generative Relevance Feedback (GRF), using text generated by Large Language Models (LLMs), can enhance the effectiveness of query expansion. However, LLMs can generate irrelevant information that harms retrieval effectiveness. To address this, we propose Generative Relevance Modeling (GRM) that uses Relevance-Aware Sample Estimation (RASE) for more accurate weighting of expansion terms. Specifically, we identify similar real documents for each generated document and use a neural re-ranker to estimate their relevance. Experiments on three standard document ranking benchmarks show that GRM improves MAP by 6-9% and R@1k by 2-4%, surpassing previous methods.

Hierarchical Wilson–Cowan Models And Connection Matrices, Wilson A. Zuniga-Galindo, Brian A. Zambrano-Luna

School of Mathematical and Statistical Sciences Faculty Publications and Presentations

This work aims to study the interplay between the Wilson–Cowan model and connection matrices. These matrices describe cortical neural wiring, while Wilson–Cowan equations provide a dynamical description of neural interaction. We formulate Wilson–Cowan equations on locally compact Abelian groups. We show that the Cauchy problem is well posed. We then select a type of group that allows us to incorporate the experimental information provided by the connection matrices. We argue that the classical Wilson–Cowan model is incompatible with the small-world property. A necessary condition to have this property is that the Wilson–Cowan equations be formulated on a compact group. We …

Exploring The Relationship Between Green Space And Academic Performance, Audrey Demeaux

University Honors Theses

A growing body of literature is exploring the possibility that the presence of green spaces near schools can work to improve academic performance. Research to date on the relationship between green space and academic performance has shown mixed results. However, some see incorporating green spaces into school layouts as a key alternative strategy for improving academic achievement in the United States. This paper adds to the emerging discourse on the relationship between green space and academic achievement by using open-source data to conduct a regression analysis exploring the possible relationship between green space near K-12 schools and SAT scores in …

The Power Of (Virtual) Convergence: The Unrealized Potential Of Pair Programming And Remote Work, Mikayla Maki

University Honors Theses

Remote work is expensive. It can lead to isolation, miscommunications, and ossified organizations. These problems occur because of a synchronicity mismatch between how we need to communicate as humans, and what today's tools are capable of. This mismatch can be solved by the adoption of remote pair programming, as exemplified by the authors work at a startup (Zed). Pair programming provides the organic, synchronous, reciprocal interaction necessary to develop the sorts of relationships that remote firms currently lack.

Addressing The Impact Of Time-Dependent Social Groupings On Animal Survival And Recapture Rates In Mark-Recapture Studies, Alexandru M. Draghici

Electronic Thesis and Dissertation Repository

Mark-recapture (MR) models typically assume that individuals under study have independent survival and recapture outcomes. One such model of interest is known as the Cormack-Jolly-Seber (CJS) model. In this dissertation, we conduct three major research projects focused on studying the impact of violating the independence assumption in MR models along with presenting extensions which relax the independence assumption. In the first project, we conduct a simulation study to address the impact of failing to account for pair-bonded animals having correlated recapture and survival fates on the CJS model. We examined the impact of correlation on the likelihood ratio test (LRT), …

Effect Of Plant Population And Phosphorus Fertilizer Application On Dry Matter And Seed Yield Of Two Lablab (Lablab Purpureus) Varieties In Botswana, K. C. Kawonga, F. P. Wandera, S. Mangope, P. Mutshewa, B. M. Lefofe

IGC Proceedings (1993-2023)

Lablab has high potential as a protein source to grazing livestock especially during the dry season in arid Botswana. It produced 8.5t dry matter (DM)/ha and had 14% crude protein with 60% digestibility (APRU, 1988; Aganga, 2003). Lack of agronomic data on lablab production was probably the reason why some farmers in Botswana got yields as low as 300 kg/ha (APRU, 1987). Therefore, a trial of two lablab varieties was conducted to determine the effect of plant population and phosphorus (P) on DM yield.