351 research outputs found

    Modelling the complex dynamics of vegetation livestock and rainfall in a semiarid rangeland in South Africa

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    Predicting the effect of different management strategies on range condition is a challenge for farmers in highly variable environments. A model that explains how the relations between rainfall, livestock and vegetation composition vary over time and interact is needed. Rangeland ecosystems have a hierarchical structure that can be described in terms of vegetation composition, stocking rate and rainfall at the ecosystem level, and the performance of individual animals and plants at the lower level. In this paper, we present mathematical models that incorporate ideas from complex systems theory to integrate several strands of rangeland theory in a hierarchical framework. Compared with observed data from South Africa, the model successfully predicted the relationship between rainfall, vegetation composition and animal numbers over 30 years. Extending model runs over 100 years suggested that initial starting conditions can have a major effect on rangeland dynamics (divergence), and that hysteresis is more likely during a series of low rainfall years. Our model suggests that applying an upper threshold to animal numbers may help to conserve the biodiversity and resilience of grazing systems, whilst maintaining farmers’ ability to respond to changing environmental conditions, a management option here termed controlled disequilibrium

    Portable Sensory Room for the West Orange County Consortium for Special Education

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    This report discusses the development of a Portable Sensory Room to be used at Newland Elementary School in Huntington Beach. Newland Elementary has an exceptional Special Needs program that teaches the children with the most severe cases of autism in its school district. People with autism typically also have sensory processing disorders, which can be extremely disruptive for a child’s development and can make it difficult for a child to be able to concentrate long enough to gain necessary life skills. The idea behind a Sensory Rooms is to create a place to calm the students and to expose them to new stimuli to explore and learn in a calm and non-threatening environment. There are three different Special Needs classrooms that the Portable Sensory Room will be moved between in a single day. The teachers at Newland Elementary also desired a swing element and a pressure applying device. Both of these components are used regularly in Occupational Therapy with children with autism and have been proven to help children develop necessary skills in life. The design of the Portable Sensory Room, which was composed of several brainstorming sessions and decision matrices, lasted several months from Fall 2015 to midway through the Winter 2016 quarter. The final design consists of seven different components - five of the components act as the structure of the room and can easily connect to one another to achieve a uniform enclosure and two are separate from the room structure. All of these components have interactions on their faces that either comfort or challenge the children and all contribute to a calming sea theme throughout. The components are all on locking casters which makes transportation of the assembly easy. The five components of the room structure are: the tactile wall, the bookshelf, the tactile station, the fabric panels, and the LED panels. The tactile wall focuses on helping the children gain fine motor skills by use of tracks that the children can move fish along, a moveable gear set, and a whiteboard. The bookshelf is filled with activities for fine motor skills as well, and provides extra storage for the teachers to arrange according to their desires. The tactile station is a dresser with calming light effects at the top. The drawers can be completely removed and put on the floor, where the children can play with tactile interactions in an enclosed space to avoid a mess. The fabric panels provide tactile sensations using several swatches of fabric that range from calming to challenging. The LED panels have a calming ocean mural and also allow children to observe the notion of cause-and-effect via a control box that changes the light display. The other two components are the swing structure and the pressure applicator, which can either be used in the room or separately from the room depending on the teachers’ preferences. The swing structure was purchased from Amazon and allows for a 360 degree rotation. The pressure applicator was built by the team and is comprised of two horizontal rollers that the child can slide in between. The addition of rubber bands allows the child/teacher to choose how much pressure will be exerted on the child. The build phase of the project lasted from the end of Winter 2016 quarter to the end of Spring 2016 quarter. All of the components were made from lumber and sanded down in order to avoid any sharp edges. Testing was performed to verify that the teachers would not have to exert an enormous effort to move all of the components, as well as to determine the tipping loads for each of the components. The tipping loads were below the desired specification; in order to mitigate this, two adults will be required to move each component. When the room is assembled together, the entire structure is quite stable and does not pose a tipping hazard. The final product will be delivered to Newland Elementary School on June 17th, 2016

    Warming Climate Changes Vermont Disease

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    Introduction: •The average annual temperature in Vermont has gradual increased roughly 1° Centigrade with an increase of 1.16 inches of annual precipitation over the past 112 years. •According to expert analysis, humans are responsible for 60% of the warming overthe past 140 years. •Projected greater than 1° Centigrade increase in global temperature by 2100 and a correlated rise in precipitation. •Climate changes result in the introduction and reproduction of non-endemic flora and fauna. •Vector-borne diseases accompany warming trends and can become endemic and cause new illnesses in areas which were previously uninhabitable.https://scholarworks.uvm.edu/comphp_gallery/1006/thumbnail.jp

    Biomass Yield of Switchgrass Cultivars under High- versus Low-Input Conditions

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    Switchgrass (Panicum virgatum L.) is undergoing development as a biomass crop to support conversion of cellulosic biomass to energy. To avoid the competition of biomass with food or feed crops, most commercialization proposals suggest that switchgrass should be grown exclusively on marginal lands that are not fit for food or feed production. The objective of this study was to investigate the potential for cultivar x environment interactions that would affect the methods and approaches for breeding and evaluating switchgrass cultivars, including both upland and lowland types, for high-input versus low-input types of environments. Biomass yield was measured on 14 cultivars that were present in 28 replicated field experiments representing seven regions, ranging from 75 to 100° W and spanning USDA Hardiness Zones 4 through 7. Region was the most important environmental factor interacting with cultivars, supporting the idea that the north-central and northeastern United States should have independent switchgrass breeding programs. Cultivars interacted with soil phosphorus concentration in New Jersey and with depth of the A and B horizons in New York and showed mild interactions with rate of nitrogen fertilizer at several locations. Cultivar rank correlation coefficients between the two rates of nitrogen fertilization (100 vs. 0 kg N ha−1) ranged from 0.23 to 0.88, suggesting a possible benefit to breeding and selection without applied nitrogen fertilizer

    A paleoecological context for forest distribution and restoration in Grootbos Nature Reserve, Agulhas Plain, South Africa

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    Grootbos Nature Reserve falls within the Cape Floristic Region of South Africa and comprises fynbos and forest vegetation elements, which exist as alternate stable states and are naturally maintained by feedbacks between vegetation, fire, topography and climate. The objective of this study was to investigate changes in forest extent in the Baviaansfontein valley in Grootbos Nature Reserve in order to understand whether current forest coverage was greater or lesser prior to colonial settlement. Incorporating paleoecology has the potential to define historical ranges of landscape variability that can guide forest restoration programs that are aligned to historical forest occurrence. Not all landscapes are suited for tree planting initiatives as they harbor indigenous open vegetation, which is of conservation value. Historical and palaeoecological information is especially valuable as tree planting initiatives and reforestation programs are becoming more popular. Here we present a combined palynological (pollen, spores, charcoal) and geochemical approach (X-ray fluorescence elemental ratios, Loss-on-ignition), to evaluate the historic extent and distribution of forest and fynbos vegetation for the past ~250 years at Baviaansfontein in the Grootbos Nature Reserve. The start of the record was dominated by pollen typical of asteraceous fynbos, with evidence of forest elements also present, though in low abundance. After 200 years (c.1750 CE–1950 CE) of increased input of micro- and macrocharcoal, the subsequent decline in charcoal indicates a decrease in fire occurrence. This decline coincides with increased input of forest pollen taxa, suggesting that fire suppression most likely triggered forest expansion and perhaps initiated the beginning of a biome boundary shift. The continued decline in fire promoted the development of the present-day proteoid fynbos type around ~1980 CE and was responsible for the replacement of the previously more asteraceous-dominated fynbos type. The results show that changes in fire occurrence have driven compositional changes over time within fynbos but also contributed to the expansion of forest at the expense of fynbos. Considering the palaeoecological record and the expected warmer climate with more fires, forest expansion at Baviaansfontein is not recommended. The proteoid-dominated fynbos biome might be similarly negatively affected by warmer climate and a shift to an asteraceous fynbos community could occur in the future

    The Grizzly, February 6, 2003

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    Fallen Heroes: Space Shuttle Columbia Disaster • Best Buddies Goes Under da Sea • A New Semester Means New Members for Ursinus Greeks • The World Beyond Ursinus: Study Abroad Experience • Plans in Progress: Contemporary Design Class Visits NYC • The Hunt for J.D. Salinger: Ursinus\u27 Most Mysterious Alumnus • Spring Break from Winter Fashions • Beat of a Different Drummer • D.C. Demonstration: First Hand Account • Fallen Angels: East Asian Film Introduction • Pledging in the Past • Bridget Hussey Scores 1,000 • Strong Season for Men\u27s Basketball • Women\u27s Basketball Having Ups and Downs • Nolan Named Honorable Mentionhttps://digitalcommons.ursinus.edu/grizzlynews/1528/thumbnail.jp

    Promoting Diversity and Combatting Discrimination in Research Organizations: A Practitioner’s Guide

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    The essay is addressed to practitioners in research management and from academic leadership. It describes which measures can contribute to creating an inclusive climate for research teams and preventing and effectively dealing with discrimination. The practical recommendations consider the policy and organizational levels, as well as the individual perspective of research managers. Following a series of basic recommendations, six lessons learned are formulated, derived from the contributions to the edited collection on "Diversity and Discrimination in Research Organizations.

    Clinical, radiologic, pathologic, and molecular characteristics of long-term survivors of diffuse intrinsic pontine glioma (DIPG): a collaborative report from the International and European Society for Pediatric Oncology DIPG registries

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    Purpose Diffuse intrinsic pontine glioma (DIPG) is a brainstem malignancy with a median survival of < 1 year. The International and European Society for Pediatric Oncology DIPG Registries collaborated to compare clinical, radiologic, and histomolecular characteristics between short-term survivors (STSs) and long-term survivors (LTSs). Materials and Methods Data abstracted from registry databases included patients from North America, Australia, Germany, Austria, Switzerland, the Netherlands, Italy, France, the United Kingdom, and Croatia. Results Among 1,130 pediatric and young adults with radiographically confirmed DIPG, 122 (11%) were excluded. Of the 1,008 remaining patients, 101 (10%) were LTSs (survival ≥ 2 years). Median survival time was 11 months (interquartile range, 7.5 to 16 months), and 1-, 2-, 3-, 4-, and 5-year survival rates were 42.3% (95% CI, 38.1% to 44.1%), 9.6% (95% CI, 7.8% to 11.3%), 4.3% (95% CI, 3.2% to 5.8%), 3.2% (95% CI, 2.4% to 4.6%), and 2.2% (95% CI, 1.4% to 3.4%), respectively. LTSs, compared with STSs, more commonly presented at age < 3 or > 10 years (11% v 3% and 33% v 23%, respectively; P < .001) and with longer symptom duration ( P < .001). STSs, compared with LTSs, more commonly presented with cranial nerve palsy (83% v 73%, respectively; P = .008), ring enhancement (38% v 23%, respectively; P = .007), necrosis (42% v 26%, respectively; P = .009), and extrapontine extension (92% v 86%, respectively; P = .04). LTSs more commonly received systemic therapy at diagnosis (88% v 75% for STSs; P = .005). Biopsies and autopsies were performed in 299 patients (30%) and 77 patients (10%), respectively; 181 tumors (48%) were molecularly characterized. LTSs were more likely to harbor a HIST1H3B mutation (odds ratio, 1.28; 95% CI, 1.1 to 1.5; P = .002). Conclusion We report clinical, radiologic, and molecular factors that correlate with survival in children and young adults with DIPG, which are important for risk stratification in future clinical trials

    Reduced blood flow through intrapulmonary arteriovenous anastomoses at rest and during exercise in lowlanders during acclimatization to high altitude

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    Blood flow through intrapulmonary arteriovenous anastomoses (QIPAVA ) is elevated during exercise at sea level (SL) and at rest in acute normobaric hypoxia. Following high altitude (HA) acclimatization, resting QIPAVA is similar to SL, but it is unknown if this is true during exercise at HA. We reasoned that exercise at HA (5,050 m) would exacerbate QIPAVA due to heightened pulmonary arterial pressure. Using a supine cycle ergometer, seven healthy adults free from intracardiac shunts underwent an incremental exercise test at SL (25, 50, 75% of SL VO2peak ) and at HA (25, 50% of SL VO2peak ). Echocardiography was used to determine cardiac output (Q) and pulmonary artery systolic pressure (PASP) and agitated saline contrast was used to determine QIPAVA (bubble score; 0-5). The principal findings were: (1) Q was similar at SL-rest (3.9 +/- 0.47 l min-1 ) compared with HA-rest (4.5 +/- 0.49 l min-1 ; P = 0.382), but increased from rest during both SL and HA exercise (P < 0.001); (2) PASP increased from SL-rest (19.2 +/- 0.7 mmHg) to HA-rest (33.7 +/- 2.8 mmHg; P = 0.001) and, compared with SL, PASP was further elevated during HA exercise (P = 0.003); (3) QIPAVA was increased from SL-rest (0) to HA-rest (median = 1; P = 0.04) and increased from resting values during SL exercise (P < 0.05), but were unchanged during HA exercise (P = 0.91), despite significant increases in Q and PASP. Theoretical modeling of microbubble dissolution suggests that the lack of QIPAVA in response to exercise at HA is unlikely caused by saline contrast instability

    Evaluation of the safety of C-spine clearance by paramedics: design and methodology

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    <p>Abstract</p> <p>Background</p> <p>Canadian Emergency Medical Services annually transport 1.3 million patients with potential neck injuries to local emergency departments. Less than 1% of those patients have a c-spine fracture and even less (0.5%) have a spinal cord injury. Most injuries occur before the arrival of paramedics, not during transport to the hospital, yet most patients are transported in ambulances immobilized. They stay fully immobilized until a bed is available, or until physician assessment and/or X-rays are complete. The prolonged immobilization is often unnecessary and adds to the burden of already overtaxed emergency medical services systems and crowded emergency departments.</p> <p>Methods/Design</p> <p>The goal of this study is to evaluate the safety and potential impact of an active strategy that allows paramedics to assess very low-risk trauma patients using a validated clinical decision rule, the Canadian C-Spine Rule, in order to determine the need for immobilization during transport to the emergency department.</p> <p>This cohort study will be conducted in Ottawa, Canada with one emergency medical service. Paramedics with this service participated in an earlier validation study of the Canadian C-Spine Rule. Three thousand consecutive, alert, stable adult trauma patients with a potential c-spine injury will be enrolled in the study and evaluated using the Canadian C-Spine Rule to determine the need for immobilization. The outcomes that will be assessed include measures of safety (numbers of missed fractures and serious adverse outcomes), measures of clinical impact (proportion of patients transported without immobilization, key time intervals) and performance of the Rule.</p> <p>Discussion</p> <p>Approximately 40% of all very low-risk trauma patients could be transported safely, without c-spine immobilization, if paramedics were empowered to make clinical decisions using the Canadian C-Spine Rule. This safety study is an essential step before allowing all paramedics across Canada to selectively immobilize trauma victims before transport. Once safety and potential impact are established, we intend to implement a multi-centre study to study actual impact.</p> <p>Trial Registration</p> <p>ClinicalTrials.gov <a href="http://www.clinicaltrials.gov/ct2/show/NCT01188447">NCT01188447</a></p
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