486 research outputs found
The Effects of Prescribed Fire on the Herbaceous Layer in the Southern Appalachian Mountains.
Prescribed fire in the southern Appalachians is a frequently used and controversial forest management practice. Research is limited on the effects of prescribed fire in the mesic southern Appalachians, where many of Tennessee\u27s rare and regionally endemic plant species occur. This study examined the effects of prescribed fire on the herbaceous layer. Field work was conducted on six previously burned sites within the Cherokee National Forest in northeast Tennessee. Complimentary non-burned sites were selected based on similarity of physical characteristics and forest structure. The numbers of herbaceous species and individuals and the total numbers of species and individuals were determined and used to compare burned and unburned forest. Following prescribed fires there were significant reductions in the number of herbaceous species and individuals. Species with myrmecochorous (ant-dispersed) seeds were markedly reduced on burned sites. Despite considerable variation among sites, the negative impact of fire on forest herbs was clearly evident
A Review of 105 Consecutive Uniport Endoscopic Plantar Fascial Release Procedures for the Treatment of Chronic Plantar Fasciitis
Plantar fasciitis is a common cause of heel pain in the U.S. Army soldier, resulting in a significant loss of man hours. Given the heavy operations tempo of the U.S. military, successful treatment options need to be considered and used as quickly as possible. Plantar fasciitis can be successfully treated in up to 90% of patients using conservative measures. Operative intervention might need to be considered for those in whom conservative measures have failed. The present report is a review of 105 consecutive uniport endoscopic plantar fascial release procedures performed by the principal investigator during a 9-year period. The following data were collected and analyzed: gender, age, weight, height, body mass index, medical treatment facility, procedure laterality, preoperative pain levels, postoperative pain levels at 3 months, first ambulatory day in the controlled ankle motion boot, return to activity as tolerated, and complications. Three major points were of interest: evidence of improvement in chronic plantar fasciitis when treated with uniport endoscopic procedures; the patient attributes associated with self-reported pain levels 90 days postoperatively; and the patient attributes associated with the average time until patients were able to return to activities as tolerated in a controlled ankle motion boot. It was noted that 44.5% of those with a body mass index of 29.80 kg/m2 or greater reported a postoperative pain level of 0; and 96.3% of those with a body mass index of 25.53 kg/m2 or less reported postoperative pain levels of 0. The analyzed data were used to characterize the clinical outcomes of the procedure, identify changes in outcome with surgeon experience, and identify whether certain patient subgroups have better outcomes, allowing surgeons to identify which patient might be the best candidates for an endoscopic release procedure
A Review of 105 Consecutive Uniport Endoscopic Plantar Fascial Release Procedures for the Treatment of Chronic Plantar Fasciitis
Plantar fasciitis is a common cause of heel pain in the U.S. Army soldier, resulting in a significant loss of man hours. Given the heavy operations tempo of the U.S. military, successful treatment options need to be considered and used as quickly as possible. Plantar fasciitis can be successfully treated in up to 90% of patients using conservative measures. Operative intervention might need to be considered for those in whom conservative measures have failed. The present report is a review of 105 consecutive uniport endoscopic plantar fascial release procedures performed by the principal investigator during a 9-year period. The following data were collected and analyzed: gender, age, weight, height, body mass index, medical treatment facility, procedure laterality, preoperative pain levels, postoperative pain levels at 3 months, first ambulatory day in the controlled ankle motion boot, return to activity as tolerated, and complications. Three major points were of interest: evidence of improvement in chronic plantar fasciitis when treated with uniport endoscopic procedures; the patient attributes associated with self-reported pain levels 90 days postoperatively; and the patient attributes associated with the average time until patients were able to return to activities as tolerated in a controlled ankle motion boot. It was noted that 44.5% of those with a body mass index of 29.80 kg/m2 or greater reported a postoperative pain level of 0; and 96.3% of those with a body mass index of 25.53 kg/m2 or less reported postoperative pain levels of 0. The analyzed data were used to characterize the clinical outcomes of the procedure, identify changes in outcome with surgeon experience, and identify whether certain patient subgroups have better outcomes, allowing surgeons to identify which patient might be the best candidates for an endoscopic release procedure
Endocrine Dysfunction Criteria in Critically Ill Children: The PODIUM Consensus Conference
CONTEXT
Endocrine dysfunction is common in critically ill children and is manifested by abnormalities in glucose, thyroid hormone, and cortisol metabolism.
OBJECTIVE
To develop consensus criteria for endocrine dysfunction in critically ill children by assessing the association of various biomarkers with clinical and functional outcomes.
DATA SOURCES
PubMed and Embase were searched from January 1992 to January 2020.
STUDY SELECTION
We included studies in which researchers evaluated critically ill children with abnormalities in glucose homeostasis, thyroid function and adrenal function, performance characteristics of assessment and/or scoring tools to screen for endocrine dysfunction, and outcomes related to mortality, organ-specific status, and patient-centered outcomes. Studies of adults, premature infants or animals, reviews and/or commentaries, case series with sample size ≤10, and non-English-language studies were excluded.
DATA EXTRACTION
Data extraction and risk-of-bias assessment for each eligible study were performed by 2 independent reviewers.
RESULTS
The systematic review supports the following criteria for abnormal glucose homeostasis (blood glucose [BG] concentrations >150 mg/dL [>8.3 mmol/L] and BG concentrations <50 mg/dL [<2.8 mmol/L]), abnormal thyroid function (serum total thyroxine [T4] <4.2 μg/dL [<54 nmol/L]), and abnormal adrenal function (peak serum cortisol concentration <18 μg/dL [500 nmol/L]) and/or an increment in serum cortisol concentration of <9 μg/dL (250 nmol/L) after adrenocorticotropic hormone stimulation.
LIMITATIONS
These included variable sampling for BG measurements, limited reporting of free T4 levels, and inconsistent interpretation of adrenal axis testing.
CONCLUSIONS
We present consensus criteria for endocrine dysfunction in critically ill children that include specific measures of BG, T4, and adrenal axis testing
Viscosity and Diffusion: Crowding and Salt Effects in Protein Solutions
We report on a joint experimental-theoretical study of collective diffusion
in, and static shear viscosity of solutions of bovine serum albumin (BSA)
proteins, focusing on the dependence on protein and salt concentration. Data
obtained from dynamic light scattering and rheometric measurements are compared
to theoretical calculations based on an analytically treatable spheroid model
of BSA with isotropic screened Coulomb plus hard-sphere interactions. The only
input to the dynamics calculations is the static structure factor obtained from
a consistent theoretical fit to a concentration series of small-angle X-ray
scattering (SAXS) data. This fit is based on an integral equation scheme that
combines high accuracy with low computational cost. All experimentally probed
dynamic and static properties are reproduced theoretically with an at least
semi-quantitative accuracy. For lower protein concentration and low salinity,
both theory and experiment show a maximum in the reduced viscosity, caused by
the electrostatic repulsion of proteins. The validity range of a generalized
Stokes-Einstein (GSE) relation connecting viscosity, collective diffusion
coefficient, and osmotic compressibility, proposed by Kholodenko and Douglas
[PRE 51, 1081 (1995)] is examined. Significant violation of the GSE relation is
found, both in experimental data and in theoretical models, in semi-dilute
systems at physiological salinity, and under low-salt conditions for arbitrary
protein concentrations
PER-TIM Interactions with the Photoreceptor Cryptochrome Mediate Circadian Temperature Responses in Drosophila
Drosophila cryptochrome (CRY) is a key circadian photoreceptor that interacts with the period and timeless proteins (PER and TIM) in a light-dependent manner. We show here that a heat pulse also mediates this interaction, and heat-induced phase shifts are severely reduced in the cryptochrome loss-of-function mutant cryb. The period mutant perL manifests a comparable CRY dependence and dramatically enhanced temperature sensitivity of biochemical interactions and behavioral phase shifting. Remarkably, CRY is also critical for most of the abnormal temperature compensation of perL flies, because a perL; cryb strain manifests nearly normal temperature compensation. Finally, light and temperature act together to affect rhythms in wild-type flies. The results indicate a role for CRY in circadian temperature as well as light regulation and suggest that these two features of the external 24-h cycle normally act together to dictate circadian phase
Olefin cross metathesis and ring-closing metathesis in polymer chemistry
The use of olefin cross metathesis in preparing functional polymers, through either pre-functionalisation of monomers or post-polymerisation functionalisation is growing in both scope and breadth. The broad functional group tolerance of olefin metathesis offers a wealth of opportunities for introducing a broad range of functional groups into the polymer backbone, tuning polymer properties and expanding potential applications. Similarly, ring-closing metathesis offers the ability to tune the polymer macrostructure and microstructure to similar effect. In this review, we explore the importance of understanding selectivity in olefin cross metathesis in designing functional polymers, the manipulation of this reactivity to prepare (multi)functional polymers, and show how polymer systems can be constructed to favour ring closing and change backbone structure and properties
The future of interpretive accounting research:A Polyphonic Debate
In 1997-99 the three of us organised a series of European Commission funded
conferences aimed at building a network of young researchers in the area of
accounting. At the time “young” was defined by the Commission as researchers
under 35 years of age (allowing for maternity leave or national service). Over the
intervening years our network had grown and we wanted to try and take stock of the
field in which we had now been working for a surprising number of years. To that
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Accepted Manuscript
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end we put together the above email and a broad invitation list of people who had
been at those first meetings, and others of the same generation (or even younger)
whom we had met since.
About half of those originally contacted managed to make the meeting where we
spent a stimulating couple of hours of debate on the topics raised below—so
stimulating that we developed a collective desire to leave a trace of the discussion.
Writing a traditional paper with so many, so widely dispersed authors was not going
to work. Instead we came up with a different form of collective writing that mirrored
the original debate, and that might contribute to ongoing debates in this journal
concerning the nature and status of our research (e.g. Arrington, 2004; Inanga &
Schneider, 2005; Macintosh, 2004). We agreed a process in which each of us in turn
would have one week to add a target of 300 words to a rolling document, going
through the contributors alphabetically. After two rounds we would see what we had
got
The Long-Baseline Neutrino Experiment: Exploring Fundamental Symmetries of the Universe
The preponderance of matter over antimatter in the early Universe, the
dynamics of the supernova bursts that produced the heavy elements necessary for
life and whether protons eventually decay --- these mysteries at the forefront
of particle physics and astrophysics are key to understanding the early
evolution of our Universe, its current state and its eventual fate. The
Long-Baseline Neutrino Experiment (LBNE) represents an extensively developed
plan for a world-class experiment dedicated to addressing these questions. LBNE
is conceived around three central components: (1) a new, high-intensity
neutrino source generated from a megawatt-class proton accelerator at Fermi
National Accelerator Laboratory, (2) a near neutrino detector just downstream
of the source, and (3) a massive liquid argon time-projection chamber deployed
as a far detector deep underground at the Sanford Underground Research
Facility. This facility, located at the site of the former Homestake Mine in
Lead, South Dakota, is approximately 1,300 km from the neutrino source at
Fermilab -- a distance (baseline) that delivers optimal sensitivity to neutrino
charge-parity symmetry violation and mass ordering effects. This ambitious yet
cost-effective design incorporates scalability and flexibility and can
accommodate a variety of upgrades and contributions. With its exceptional
combination of experimental configuration, technical capabilities, and
potential for transformative discoveries, LBNE promises to be a vital facility
for the field of particle physics worldwide, providing physicists from around
the globe with opportunities to collaborate in a twenty to thirty year program
of exciting science. In this document we provide a comprehensive overview of
LBNE's scientific objectives, its place in the landscape of neutrino physics
worldwide, the technologies it will incorporate and the capabilities it will
possess.Comment: Major update of previous version. This is the reference document for
LBNE science program and current status. Chapters 1, 3, and 9 provide a
comprehensive overview of LBNE's scientific objectives, its place in the
landscape of neutrino physics worldwide, the technologies it will incorporate
and the capabilities it will possess. 288 pages, 116 figure
The growth and evolution of cardiovascular magnetic resonance: a 20-year history of the Society for Cardiovascular Magnetic Resonance (SCMR) annual scientific sessions
Background and purpose: The purpose of this work is to summarize cardiovascular magnetic resonance (CMR) research trends and highlights presented at the annual Society for Cardiovascular Magnetic Resonance (SCMR) scientific sessions over the past 20 years. Methods: Scientific programs from all SCMR Annual Scientific Sessions from 1998 to 2017 were obtained. SCMR Headquarters also provided data for the number and the country of origin of attendees and the number of accepted abstracts according to type. Data analysis included text analysis (key word extraction) and visualization by ‘word clouds’ representing the most frequently used words in session titles for 5-year intervals. In addition, session titles were sorted into 17 major subject categories to further evaluate research and clinical CMR trends over time. Results: Analysis of SCMR annual scientific sessions locations, attendance, and number of accepted abstracts demonstrated substantial growth of CMR research and clinical applications. As an international field of study, significant growth of CMR was documented by a strong increase in SCMR scientific session attendance (> 500%, 270 to 1406 from 1998 to 2017, number of accepted abstracts (> 700%, 98 to 701 from 1998 to 2018) and number of international participants (42–415% increase for participants from Asia, Central and South America, Middle East and Africa in 2004–2017). ‘Word clouds’ based evaluation of research trends illustrated a shift from early focus on ‘MRI technique feasibility’ to new established techniques (e.g. late gadolinium enhancement) and their clinical applications and translation (key words ‘patient’, ‘disease’) and more recently novel techniques and quantitative CMR imaging (key words ‘mapping’, ‘T1’, ‘flow’, ‘function’). Nearly every topic category demonstrated an increase in the number of sessions over the 20-year period with ‘Clinical Practice’ leading all categories. Our analysis identified three growth areas ‘Congenital’, ‘Clinical Practice’, and ‘Structure/function/flow’. Conclusion: The analysis of the SCMR historical archives demonstrates a healthy and internationally active field of study which continues to undergo substantial growth and expansion into new and emerging CMR topics and clinical application areas
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