University of Vermont

About: University of Vermont is a education organization based out in Burlington, Vermont, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 17592 authors who have published 38251 publications receiving 1609874 citations. The organization is also known as: UVM & University of Vermont and State Agricultural College.

Water‐stress‐induced xylem embolism in three species of conifers

Abstract: . The mechanism of water-stress-induced xylem embolism was studied in three species of conifers: Abies balsamea (L.) Mill., Picca rubens Sarg, and Juniperus virginiana L. Each species showed a characteristic relationship between xylem tension and the loss of hydraulic conductivity by air embolism. Abics balsamea and Picca rubens began to embolize at tensions between 2 and 3 MPa and were completely non-conducting between 3 and 4 MPa. Juniperus virginiana was least vulnerable, beginning to embolize at 4 and still retaining approximately 10% conductivity at 10 MPa. As with a previous study of the vessel-bearing Accr saccharum Marsh., a brief perfusion of branch segments with an oxalic acid and calcium solution (10 and 0.1 mol m−3. respectively) increased the vulnerability of the xylem to embolism; this was especially pronounced in Abies balsamea. In order to test whether embolism was caused by aspiration of air into functional tracheids from neighbouring embolized, ones (the ‘air-seeding’hypothesis), hydrated branch segments were injected with air at various pressures and measured for embolism. Results supported the air-seeding hypothesis because the relationship between injection pressure and embolism for both native and oxalic-calcium-treated segments was essentially the same as for embolism induced by xylem tension. Structural and experimental evidence suggested the air seeding occurred through inter-tracheid pit membranes when the thickened torus region of the membrane became displaced from its normal sealing position over the pit aperture. Thus, the embolism-inducing tension may be a function of pit membrane flexibility. This tension is of ecological significance because it reflects to some extent the range of xylem tensions to which a species is adapted.

Effects of obesity and bariatric surgery on airway hyperresponsiveness, asthma control, and inflammation

Abstract: Background Asthma in obese subjects is poorly understood, and these patients are often refractory to standard therapy. Objectives We sought to gain insights into the pathogenesis and treatment of asthma in obese subjects by determining how obesity and bariatric surgery affect asthma control, airway hyperresponsiveness (AHR), and markers of asthmatic inflammation. Methods We performed a prospective study of (1) asthmatic and nonasthmatic patients undergoing bariatric surgery compared at baseline and (2) asthmatic patients followed for 12 months after bariatric surgery. Results We studied 23 asthmatic and 21 nonasthmatic patients undergoing bariatric surgery. At baseline, asthmatic patients had lower FEV 1 and forced vital capacity and lower numbers of lymphocytes in bronchoalveolar lavage fluid. After surgery, asthmatic participants experienced significant improvements in asthma control (asthma control score, 1.55 to 0.74; P P 20 , 3.9 to 7.28, P = .03). There was a statistically significant interaction between IgE status and change in airways responsiveness ( P for interaction = .01). The proportion of lymphocytes in bronchoalveolar lavage fluid and the production of cytokines from activated peripheral blood CD4 + T cells increased significantly. Conclusions Bariatric surgery improves AHR in obese asthmatic patients with normal serum IgE levels. Weight loss has dichotomous effects on airway physiology and T-cell function typically involved in the pathogenesis of asthma, suggesting that obesity produces a unique phenotype of asthma that will require a distinct therapeutic approach.

Helping or Hovering? Effects of Instructional Assistant Proximity on Students with Disabilities:

Abstract: This study presents data on the effects of the proximity of instructional assistants on students with multiple disabilities who are placed in general education classrooms. Based on extensive observations and interviews, analyses of the data highlighted eight major findings of educational significance, all related to proximity of instructional assistants. Categories of findings and discussion include (a) interference with ownership and responsibility by general educators, (b) separation from classmates, (c) dependence on adults, (d) impact on peer interactions, (e) limitations on receiving competent instruction, (f) loss of personal control, (g) loss of gender identity, and (h) interference with instruction of other students. The article concludes with implications for practice related to policy development, training, classroom practices, and research.

A unique point mutation in the fibroblast growth factor receptor 3 gene (FGFR3) defines a new craniosynostosis syndrome.

Abstract: The underlying basis of many forms of syndromic craniosynostosis has been defined on a molecular level However, many patients with familial or sporadic craniosynostosis do not have the classical findings of those craniosynostosis syndromes Here we present 61 individuals from 20 unrelated families where coronal synostosis is due to an amino acid substitution (Pro250Arg) that results from a single point mutation in the fibroblast growth factor receptor 3 gene on chromosome 4p In this instance, a new clinical syndrome is being defined on the basis of the molecular finding In addition to the skull findings, some patients had abnormalities on radiographs of hands and feet, including thimble-like middle phalanges, coned epiphyses, and carpal and tarsal fusions Brachydactyly was seen in some cases; none had clinically significant syndactyly or deviation of the great toe Sensorineural hearing loss was present in some, and developmental delay was seen in a minority While the radiological findings of hands and feet can be very helpful in diagnosing this syndrome, it is not in all cases clearly distinguishable on a clinical basis from other craniosynostosis syndromes Therefore, this mutation should be tested for in patients with coronal synostosis