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Articles 4951 - 4980 of 302419

Full-Text Articles in Physical Sciences and Mathematics

Study Of The Effect Of Combined Reinforcement And Modification Of Epoxy Resin With Rubbers On The Impact Strength Of Carbon Fiber-Reinforced Plastic, M. N. Meiirbekov, M. B. Ismailov, A. K. Kenzhegulov, L. M. Mustafa, I. B. Tashmukhanbetova Mar 2024

Study Of The Effect Of Combined Reinforcement And Modification Of Epoxy Resin With Rubbers On The Impact Strength Of Carbon Fiber-Reinforced Plastic, M. N. Meiirbekov, M. B. Ismailov, A. K. Kenzhegulov, L. M. Mustafa, I. B. Tashmukhanbetova

Eurasian Journal of Physics and Functional Materials

The effect of modified epoxy resin with polyurethane, silicone, and butadiene rubber and combined reinforcement with fiberglass and Kevlar on the strength properties of carbon fiber-reinforced plastic was studied. It was found that when rubber is introduced into the composition of the epoxy resin, polyurethane, and combined reinforcement according to the carbon fiber/Kevlar scheme in a ratio of 10:10 leads to an increase in impact strength by 42% to 273 kJ/m2 and compressive strength increases by 35% to 575 MPa


Luminescence And Creation Of Electron-Hole Trapping Centers In Alkali Metal Sulfates Activated By Pb2+ Impurity, T. N. Nurakhmetov, R. K. Shamieva, Zh. M. Salikhodzha, N. I. Temirkulova, T. T. Alibay, B. M. Sadykova, B. N. Yussupbekova, A. A. Kabdulkak Mar 2024

Luminescence And Creation Of Electron-Hole Trapping Centers In Alkali Metal Sulfates Activated By Pb2+ Impurity, T. N. Nurakhmetov, R. K. Shamieva, Zh. M. Salikhodzha, N. I. Temirkulova, T. T. Alibay, B. M. Sadykova, B. N. Yussupbekova, A. A. Kabdulkak

Eurasian Journal of Physics and Functional Materials

The nature of the impurity emission and the process of creating intrinsic and impurity electron-hole trapping centers were studied by spectroscopic and thermal activation methods in Na2SO4 - Pb and K2SO4 - Pb phosphors. The combined radiative electronic state is formed from intrinsic SO3− 4 - SO− 4 and impurity Pb+ - SO− 4 electron-hole trapping centers in UV-irradiated phosphors with a photon en- ergy of 6.2 eV at 80 K. Emissions of 3.2 eV and 3.6 eV resulting from irradiation with photons with an energy of 6.2 eV are associated with intracenter transitions of 3p1 - 1s0 in Pb2+ …


Concentration Polarization And Ionic Conductivity Of Nanocomposite Thermoelectric Materials K0.01cu1.94s, K0.02cu1.94s, K0.03cu1.94s, M. M. Kubenova, M. Kh. Balapanov, K. A. Kuterbekov, B. Akhmetgaliev, R. Kh. Ishembetov, R. F. Almukhametov, M. Zeleev, A. M. Kabyshev, K. Zh. Bekmyrza, R. Alina, R. E. Kondakirov, M. K. Kenzhebek Mar 2024

Concentration Polarization And Ionic Conductivity Of Nanocomposite Thermoelectric Materials K0.01cu1.94s, K0.02cu1.94s, K0.03cu1.94s, M. M. Kubenova, M. Kh. Balapanov, K. A. Kuterbekov, B. Akhmetgaliev, R. Kh. Ishembetov, R. F. Almukhametov, M. Zeleev, A. M. Kabyshev, K. Zh. Bekmyrza, R. Alina, R. E. Kondakirov, M. K. Kenzhebek

Eurasian Journal of Physics and Functional Materials

The paper presents experimental results of concentration polarization and ionic conductivity of nanocom- posite thermoelectric materials K0.01Cu1.94S , K0.02Cu1.94S , K0.03Cu1.94S . According to X-ray phase analysis, the synthesized samples are monoclinic jarleite Cu1.93÷1.97S with an admixture of oxygen ox- ide Cu2S and monoclinic chalcocyte. High values of total ionic conductivity are observed, ranging from 0.86 to 1.5 Cm/cm. The lowest ionic conductivity (0.86 Cm/cm at 355 ◦ C) is observed for alloy K0.02Cu1.94S . In addition, it was found that with an increase in the concentration of potassium in the studied materials, ionic conductivity tends to decrease, activation energy …


Where East Meets West: Phylogeography Of The High Arctic North American Brant Goose, Robert E. Wilson, W. Sean Boyd, Sarah A. Sonsthagen, David H. Ward, Preben Clausen, Kathryn M. Dickson, Barwolt S. Ebbinge, Gudmundur A. Gudmundsson, George K. Sage, Jolene R. Rearick, Dirk V. Derksen, Sandra L. Talbot Mar 2024

Where East Meets West: Phylogeography Of The High Arctic North American Brant Goose, Robert E. Wilson, W. Sean Boyd, Sarah A. Sonsthagen, David H. Ward, Preben Clausen, Kathryn M. Dickson, Barwolt S. Ebbinge, Gudmundur A. Gudmundsson, George K. Sage, Jolene R. Rearick, Dirk V. Derksen, Sandra L. Talbot

School of Natural Resources: Faculty Publications

Genetic variation in Arctic species is often influenced by vicariance during the Pleistocene, as ice sheets fragmented the landscape and displaced populations to low-and high-latitude refugia. The formation of secondary contact or suture zones during periods of ice sheet retraction has important consequences on genetic diversity by facilitating genetic connectivity between formerly isolated populations. Brant geese (Branta bernicla) are a maritime migratory waterfowl (Anseriformes) species that almost exclusively uses coastal habitats. Within North America, brant geese are characterized by two phenotypically distinct subspecies that utilize disjunct breeding and wintering areas in the northern Pacific and Atlantic. In the …


Embedding Information Literacy Practices In An Upper Division Chemistry Lab Class At A University In The United States Of America, Christopher Randles, Matilynn Lamm, Katy A. Miller Mar 2024

Embedding Information Literacy Practices In An Upper Division Chemistry Lab Class At A University In The United States Of America, Christopher Randles, Matilynn Lamm, Katy A. Miller

Faculty Scholarship and Creative Works

This poster discusses the implementation of information literacy into an upper division inorganic chemistry lab and the strategies employed to develop students’ information literacy in the laboratory course.


Butte Priority Soils Operable Unit Grove Gulch Sedimentation Bay 100% Remedial Design, Josh Bryson Mar 2024

Butte Priority Soils Operable Unit Grove Gulch Sedimentation Bay 100% Remedial Design, Josh Bryson

Silver Bow Creek/Butte Area Superfund Site

No abstract provided.


The Impact Of Data Preparation And Model Complexity On The Natural Language Classification Of Chinese News Headlines, Torrey J. Wagner, Dennis Guhl, Brent T. Langhals Mar 2024

The Impact Of Data Preparation And Model Complexity On The Natural Language Classification Of Chinese News Headlines, Torrey J. Wagner, Dennis Guhl, Brent T. Langhals

Faculty Publications

Given the emergence of China as a political and economic power in the 21st century, there is increased interest in analyzing Chinese news articles to better understand developing trends in China. Because of the volume of the material, automating the categorization of Chinese-language news articles by headline text or titles can be an effective way to sort the articles into categories for efficient review. A 383,000-headline dataset labeled with 15 categories from the Toutiao website was evaluated via natural language processing to predict topic categories. The influence of six data preparation variations on the predictive accuracy of four algorithms was …


Ex-Vivo Hippocampus Segmentation Using Diffusion-Weighted Mri, Haoteng Tang, Siyuan Dai, Eric M. Zou, Guodong Liu, Ryan Ahearn, Ryan Krafty, Michel Modo, Liang Zhan Mar 2024

Ex-Vivo Hippocampus Segmentation Using Diffusion-Weighted Mri, Haoteng Tang, Siyuan Dai, Eric M. Zou, Guodong Liu, Ryan Ahearn, Ryan Krafty, Michel Modo, Liang Zhan

Computer Science Faculty Publications and Presentations

The hippocampus is a crucial brain structure involved in memory formation, spatial navigation, emotional regulation, and learning. An accurate MRI image segmentation of the human hippocampus plays an important role in multiple neuro-imaging research and clinical practice, such as diagnosing neurological diseases and guiding surgical interventions. While most hippocampus segmentation studies focus on using T1-weighted or T2-weighted MRI scans, we explore the use of diffusion-weighted MRI (dMRI), which offers unique insights into the microstructural properties of the hippocampus. Particularly, we utilize various anisotropy measures derived from diffusion MRI (dMRI), including fractional anisotropy, mean diffusivity, axial diffusivity, and radial diffusivity, for …


Birkhoff Summation Of Irrational Rotations: A Surprising Result For The Golden Mean, Heather Moore Mar 2024

Birkhoff Summation Of Irrational Rotations: A Surprising Result For The Golden Mean, Heather Moore

University Honors Theses

This thesis presents a surprising result that the difference in a certain sums of constant rotations by the golden mean approaches exactly 1/5. Specifically, we focus on the Birkhoff sums of these rotations, with the number of terms equal to squared Fibonacci numbers. The proof relies on the properties of continued fraction approximants, Vajda's identity and the explicit formula for the Fibonacci numbers.


Spectroscopic End Point Detection With An Electron Beam Evaporator, Ryan Mcgraw Mar 2024

Spectroscopic End Point Detection With An Electron Beam Evaporator, Ryan Mcgraw

University Honors Theses

Spectroscopic end point detection is a common tool used for measuring slope changes in wavelength intensity. Using algorithms able to apply this concept, coatings will be able to be dynamically measured in real time and stopped at the appropriate level to ensure process uniformity. It is currently applied to reductive processes such as etching, where the surface will start to be eaten away, creating a plasma. When the entire amount of a material on a substrate has been eaten away, the plasma will change color as it is beginning to etch a different material. Using a spectrometer, this point where …


Quasistationary Distribution For The Invasion Model On A Complete Bipartite Graph, Clayton Allard, Iddo Ben-Ari, Shrikant Chand, Van Hovenga, Edith Lee, Julia Shapiro Mar 2024

Quasistationary Distribution For The Invasion Model On A Complete Bipartite Graph, Clayton Allard, Iddo Ben-Ari, Shrikant Chand, Van Hovenga, Edith Lee, Julia Shapiro

Journal of Stochastic Analysis

No abstract provided.


Artificial Intelligence Usage And Data Privacy Discoveries Within Mhealth, Jennifer Schulte Mar 2024

Artificial Intelligence Usage And Data Privacy Discoveries Within Mhealth, Jennifer Schulte

Research & Publications

Advancements in artificial intelligence continue to impact nearly every aspect of human life by providing integration options that aim to supplement or improve current processes. One industry that continues to benefit from artificial intelligence integration is healthcare. For years now, elements of artificial intelligence have been used to assist in clinical decision making, helping to identify potential health risks at earlier stages, and supplementing precision medicine. An area of healthcare that specifically looks at wearable devices, sensors, phone applications, and other such devices is mobile health (mHealth). These devices are used to aid in health data collection and delivery. This …


Reproduce Or Live Longer?: A Life History Analysis Of Black Bears In A Semiarid Environment, Brenden M. Orocu, Cambria Armstrong, Janene Auger, Hal L. Black, Randy T. Larsen, Brock R. Mcmillan, Mark C. Belk Mar 2024

Reproduce Or Live Longer?: A Life History Analysis Of Black Bears In A Semiarid Environment, Brenden M. Orocu, Cambria Armstrong, Janene Auger, Hal L. Black, Randy T. Larsen, Brock R. Mcmillan, Mark C. Belk

Library/Life Sciences Undergraduate Poster Competition 2024

In population demographics, each population has an age stage vital rate (fecundity and survival) in its life history that has the greatest influence on the asymptotic population growth rate, λ.

American black bears (Ursus americanus) are found throughout North America. Other studies on population demographics have focused on populations in higher resource availability areas but none in semiarid environments where resource scarcity is a result of the variable climate.

Objective

Our objective was to determine if factors influencing population dynamics of black bears in semi-arid environments were similar to factors affecting population dynamics in mesic environments where …


Cell Motion And Multicellular Organization: A Mathematical Model For Pattern Formation In The Dictyostelium Discoideum Slug, Henry Tullis, Emily Evans, John Dallon Mar 2024

Cell Motion And Multicellular Organization: A Mathematical Model For Pattern Formation In The Dictyostelium Discoideum Slug, Henry Tullis, Emily Evans, John Dallon

Library/Life Sciences Undergraduate Poster Competition 2024

Understanding multicellular behavior is key to biology and medicine

  • Embryonic development requires coordinated cell motion, differentiation
  • Wound healing also relies on emergent multicellular processes
  • Dictyostelium discoideum (Dd) has been identified as a model organism for biomedical research, partly because it is a simple example of multicellularity
  • Understanding Dd can improve, inform approaches to these tricky problems


Doubly Charged Dimers And Trimers Of Heavy Noble Gases, Gabriel Schöpfer, Stefan Bergmeister, Milan Ončák, Ianessa Stromberg, Masoomeh Mahmoodi-Darian, Paul Scheier, Olof Echt, Elisabeth Gruber Mar 2024

Doubly Charged Dimers And Trimers Of Heavy Noble Gases, Gabriel Schöpfer, Stefan Bergmeister, Milan Ončák, Ianessa Stromberg, Masoomeh Mahmoodi-Darian, Paul Scheier, Olof Echt, Elisabeth Gruber

Faculty Publications

Many doubly charged heteronuclear dimers are metastable or even thermodynamically stable with respect to charge separation. Homonuclear dicationic dimers, however, are more difficult to form. He22+ was the first noble gas dimer predicted to be metastable and, decades later, observed. Ne22+ is the only other dicationic noble gas dimer that has been detected so far. Here, we present a novel approach to form fragile dicationic species, by post-ionization of singly charged ions that are embedded in helium nanodroplets (HNDs). Bare ions are then extracted by colliding the HNDs with helium gas. We detect homonuclear doubly charged …


2024 March 21 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University Mar 2024

2024 March 21 - Tennessee Weekly Drought Summary, Tennessee Climate Office, East Tennessee State University

Tennessee Climate Office Weekly Drought Summaries

No abstract provided.


Second Inflection Point Of Supercooled Water Surface Tension Induced By Hydrogen Bonds: A Molecular-Dynamics Study, Fawaz Hrahsheh, Inshad Jum'h, Gerald Wilemski Mar 2024

Second Inflection Point Of Supercooled Water Surface Tension Induced By Hydrogen Bonds: A Molecular-Dynamics Study, Fawaz Hrahsheh, Inshad Jum'h, Gerald Wilemski

Physics Faculty Research & Creative Works

Surface Tension Of Supercooled Water Is A Fundamental Property In Various Scientific Processes. In This Study, We Perform Molecular Dynamics Simulations With The TIP4P-2005 Model To Investigate The Surface Tension Of Supercooled Water Down To 220 K. Our Results Show A Second Inflection Point (SIP) In The Surface Tension At Temperature TSIP ≈ 267.5 ± 2.3 K. Using An Extended IAPWS-E Functional Fit For The Water Surface Tension, We Calculate The Surface Excess Internal-Energy And Entropy Terms Of The Excess Helmholtz Free Energy. Similar To Prior Studies [Wang Et Al., Phys. Chem. Chem. Phys. 21, 3360 (2019); Gorfer Et Al., …


Cold And Traffic Tolerance Of Hybrid Bermudagrass And Kentucky Bluegrass In A Cool Season, Arid Climate, Caden J. Seely, H. Burgin, N. Hansen, G. Wear, Bryan G. Hopkins Mar 2024

Cold And Traffic Tolerance Of Hybrid Bermudagrass And Kentucky Bluegrass In A Cool Season, Arid Climate, Caden J. Seely, H. Burgin, N. Hansen, G. Wear, Bryan G. Hopkins

Library/Life Sciences Undergraduate Poster Competition 2024

  • Due to climate change, warm-season Hybrid Bermudagrass (HBG) is beginning to be grown in northern climates.
  • This is potentially desirable because it may use less water than traditional species.
  • However, there is concern regarding winter kill and excessively long dormant periods.
  • There is particular interest in HBG with regards to sports turf, but there is concern with its ability to withstand heavy traffic damage when grown in a cool-season climate.

Objective: Assess the cold and traffic tolerance of common Bermudagrass [CBG; Cynodon dactylon (L) Pers.] and seven triploid interspecific hybrids (HBG; Cynodon dactylon × C. transvaalensis Burtt Davy) in …


The Biomechanics Of Ursine Predation: Investigating The Force Generation And Mechanical Properties Of Bear Claws And Teeth In Predatory Behavior, Katie Dooley, Megan Doxey, Josh Jewell, Tom Smith Mar 2024

The Biomechanics Of Ursine Predation: Investigating The Force Generation And Mechanical Properties Of Bear Claws And Teeth In Predatory Behavior, Katie Dooley, Megan Doxey, Josh Jewell, Tom Smith

Library/Life Sciences Undergraduate Poster Competition 2024

  • Studied over 2,200 human-bear conflicts in North America and witnessed the shear force that bears can exert to access food and eliminate any threats.
  • Polar bears at the Hogle Zoo in Salt Lake City punctured and bent high density polyurethane (HDPE) objects when playing with them.
  • This prompted research into the force it takes bears to puncture objects with their canines and claws.


Estimating Polarization Purity With Noise, Alex Kostinski, Dan Kestner, Jothiram Vivekanandan Mar 2024

Estimating Polarization Purity With Noise, Alex Kostinski, Dan Kestner, Jothiram Vivekanandan

Michigan Tech Publications, Part 2

We formulate a problem of estimating and monitoring mismatch (unwanted departure from orthogonality) of two ostensibly orthogonal polarization channels in a fully polarimetric general device such as a polarimetric weather radar. A statistical approach is proposed by using thermal noise or, more generally, a 'polarimetric noise' class of sources. The suitable noise class of distributions is shown to be rooted in the complex multivariate Gaussian probability density function (pdf), the latter possessing a uniform pdf on the Poincare sphere (PS), with a probability measure given by a fractional surface area. To that end, we develop a parameter to estimate polarization …


The Basel Problem And Summing Rational Functions Over Integers, Pranjal Jain Mar 2024

The Basel Problem And Summing Rational Functions Over Integers, Pranjal Jain

Rose-Hulman Undergraduate Mathematics Journal

We provide a general method to evaluate convergent sums of the form ∑_{k∈Z} R(k) where R is a rational function with complex coefficients. The method is entirely elementary and does not require any calculus beyond some standard limits and convergence criteria. It is inspired by a geometric solution to the famous Basel Problem given by Wästlund (2010), so we begin by demonstrating the method on the Basel Problem to serve as a pilot application. We conclude by applying our ideas to prove Euler’s factorisation for sin x which he originally used to solve the Basel Problem.


Silvopastoral Agroforestry In Upland And Lowland Uk Grassland: Tree Growth And Animal Performance, W R. Eason, R Lavender, R O. Clements, C Duller, E Gill, M Hislop Mar 2024

Silvopastoral Agroforestry In Upland And Lowland Uk Grassland: Tree Growth And Animal Performance, W R. Eason, R Lavender, R O. Clements, C Duller, E Gill, M Hislop

IGC Proceedings (1993-2023)

Trees, individually protected from herbivore damage using plastic shelters, were planted at two densities (100 and 400 stems/ha) into sheepgrazed pasture in upland and lowland UK grassland sites in 1988. Tree and animal performance were compared with conventional forestry (no sheep) and pasture (no tree) systems. Effects on tree growth and survival are highly species and site dependent although some treatment effects did emerge. Tree shelters encouraged rapid early height growth compared to forestry controls although in some cases tree form was also adversely affected. Generally tree performance within agroforestry treatments was better at the higher planting density. Eight years …


Use Of Annual Self-Reseeding Legumes In An Oak Forest In Central Italy, P Talamucci, G Argenti, A Pardini, S Piemontese, N Stagliano Mar 2024

Use Of Annual Self-Reseeding Legumes In An Oak Forest In Central Italy, P Talamucci, G Argenti, A Pardini, S Piemontese, N Stagliano

IGC Proceedings (1993-2023)

A trial has been carried out for three years in an oak coppice geometrically thinned out of Mediterranean Central Italy, about the functioning of a pastoral system made by four different resources: native pasture, subterranean clover (Trifolium brachycalycinum Katzn. et Morley) in pure stand, strips thinned out and firebreaks improved with oversown subclover, all grazed by sheep. Subclover increased the forage yield and improved the palatabilty of the pasture and the regularity of grazing; the higher biomass intake by animals reduced the quantity of dried biomass in summer and contributed to keep low either fire hazards or flame diffusion …


The Effects Of Shelterbelts On Adjacent Pastures And Soils In A Temperate Climate, A G. Gillingham, M F. Hawke Mar 2024

The Effects Of Shelterbelts On Adjacent Pastures And Soils In A Temperate Climate, A G. Gillingham, M F. Hawke

IGC Proceedings (1993-2023)

Two trials were conducted to differentiate the direct (exposure) from the indirect (modified soil fertility due to nutrient transfer by grazing animals) effects of farm shelterbelts on associated pasture growth.Soil from close to “unmanaged”shelterbelts with dense shelter to ground level had relatively high potassium (K) levels and, in a glasshouse situation, provided more pasture growth than soil from further distances, or from adjacent to “managed” shelterbelts. Pasture grown in boxes of a common soil implanted at increasing distances from a shelterbelt also produced highest growth rates close to shelter. These results generally explain the pattern of resident pasture growth, except …


Temperate Pasture And Sheep Performance Under Radiata Pine And In Open Pasture, K M. Pollock, R J. Lucas, D B. Pownall, S E. Thomson Mar 2024

Temperate Pasture And Sheep Performance Under Radiata Pine And In Open Pasture, K M. Pollock, R J. Lucas, D B. Pownall, S E. Thomson

IGC Proceedings (1993-2023)

Forage production from years 4 to 6 of an agroforestry system at 400-600 trees per ha and pasture alone were compared for a temperate sub-humid environment. Forage production was best for lucerne pasture followed by phalaris/clover and cocksfoot/clover, and least for ryegrass/clover and the ryegrass only pastures. Total pasture production in the agroforest relative to the open pasture was from 10% more for phalaris to 20% less for lucerne. Sheep carrying capacity over all pastures was 14.6 sheep/ha in the open and 11.8 sheep/ha in the agroforest and varied by ±15% according to the pasture types.


Grazing Management Of Tagasaste (Chamaecytisus Proliferus) For Sheep And Cattle Production In Southern Australia, N J. Edwards, G M. Allen, D M. Mcneill, C M. Oldham Mar 2024

Grazing Management Of Tagasaste (Chamaecytisus Proliferus) For Sheep And Cattle Production In Southern Australia, N J. Edwards, G M. Allen, D M. Mcneill, C M. Oldham

IGC Proceedings (1993-2023)

Direct grazing of hedgerows of tagasaste (Chamaecytisus proliferus) by sheep or cattle appear to be very robust systems. Tagasaste persists under a continuous grazing regime with cattle such that plant regrowth maintained between 5 and 10 cm in length produces in excess of 215 kg of animal liveweight/ha/year. This level of production is also sustained within a rotational grazing regime. Under both grazing systems cattle production within a year is highly seasonal, with liveweight gains from young cattle peaking at 1.0-1.5 kg/head/day in winter and spring, but dropping to maintenance only by late summer-autumn. Sheep, like cattle, can …


Shrub Palatability To Rusa Deer (Cervus Timorensis Russa) In New Caledonia, C Corniaux, S Le Bel, J M. Sarrailh Mar 2024

Shrub Palatability To Rusa Deer (Cervus Timorensis Russa) In New Caledonia, C Corniaux, S Le Bel, J M. Sarrailh

IGC Proceedings (1993-2023)

The objective of this study was to determine a palatability scale of five shrub legumes to rusa deer during the dry season in New Caledonia. Acacia ampliceps and Samanea saman remain low in acceptability. Gliricidia sepium is more palatable but quite less than Leucaena leucocephala (native cultivar) and Calliandra calothyrsus (San Ramon). Therefore, since the regression of Leucaena leucocephala population, Calliandra calothyrsus could be very promising to replace it in the deer diet. On the other hand, Acacia ampliceps seems to be the most interesting shrub legume to plant in the west coast, where soil erosion, due to successive droughts …


Soil Nutrient Redistribution Pattern About The Tree In A Silvopastoral System, L C. Nwaigbo, H G. Miller, A R. Sibbald, G Hudson Mar 2024

Soil Nutrient Redistribution Pattern About The Tree In A Silvopastoral System, L C. Nwaigbo, H G. Miller, A R. Sibbald, G Hudson

IGC Proceedings (1993-2023)

The objective of this paper is to report the effect of animal-tree interactions on soil nutrient redistribution pattern in a grazed silvopastoral experiment site at Glensaugh, in NE Scotland. Scots pine (Pinus sylvestris L) tree species were planted in square lattice arrangements at 5 m x 5 m, spacing (400 stems/ha) on plots replicated over three blocks in Randomized Complete Block design on a predominantly rye grass (Lolium perenne L) pasture which was grazed by sheep yearly from April to October. Included in the design were grazed pasture plots without trees (Control). Soil samples were collected from around …


Trees For Shelter: The Implications In Agroforestry System, L C. Nwaigbo, A R. Sibbald, G Hudson Mar 2024

Trees For Shelter: The Implications In Agroforestry System, L C. Nwaigbo, A R. Sibbald, G Hudson

IGC Proceedings (1993-2023)

The objective of this study was to determine the horizontal and vertical variations in soil penetration resistance (PR) observed at tree-scale in silvopastoral plots that were grazed by sheep with and without trees. Sycamore trees (Acer pseudoplatanus L) were planted in the spring of 1988 at 10 m x 10 m spacing (100 stems/ha) at Glensaugh NE of Scotland on plots replicated over three blocks in Randomized Complete Block design on a predominantly rye grass (Lolium perenne L) pasture. Included in the design were pasture plots without trees (Control). The experiment is grazed by sheep yearly from April to …


A Silvopastoral System In The North Atlantic Zone Of Costa Rica: Combining Indigenous Timber Species With Dairy Pasture Swards, A Moulaert- Quiros, J P. Mueller, M Villarreal, R Piedra, L Villalobos Mar 2024

A Silvopastoral System In The North Atlantic Zone Of Costa Rica: Combining Indigenous Timber Species With Dairy Pasture Swards, A Moulaert- Quiros, J P. Mueller, M Villarreal, R Piedra, L Villalobos

IGC Proceedings (1993-2023)

The objective of this study was to design, establish and monitor a silvo pastoral experiment on a dairy farm in the northern Atlantic region of Costa Rica. Indigenous timber species, Vochysia guatemalensis and Hyeronima alchorneoides were used together with or without the tropical pasture legume, Arachis pintoi in a split plot design with a 4 x 2 x 2 factorial arrangement. First year establishment was good for the tree component (2.3 to 10 % mortality) but poor for A. pintoi (4 to 5 % of sward). Poor legume establishment was attributed to lax grazing management and excess competition from existing …