781 research outputs found
Extracellular Hsp72 concentration relates to a minimum endogenous criteria during acute exercise-heat exposure
Extracellular heat-shock protein 72 (eHsp72) concentration increases during exercise-heat stress when conditions elicit physiological strain. Differences in severity of environmental and exercise stimuli have elicited varied response to stress. The present study aimed to quantify the extent of increased eHsp72 with increased exogenous heat stress, and determine related endogenous markers of strain in an exercise-heat model. Ten males cycled for 90 min at 50% O2peak in three conditions (TEMP, 20°C/63% RH; HOT, 30.2°C/51%RH; VHOT, 40.0°C/37%RH). Plasma was analysed for eHsp72 pre, immediately post and 24-h post each trial utilising a commercially available ELISA. Increased eHsp72 concentration was observed post VHOT trial (+172.4%) (P<0.05), but not TEMP (-1.9%) or HOT (+25.7%) conditions. eHsp72 returned to baseline values within 24hrs in all conditions. Changes were observed in rectal temperature (Trec), rate of Trec increase, area under the curve for Trec of 38.5°C and 39.0°C, duration Trec ≥ 38.5°C and ≥ 39.0°C, and change in muscle temperature, between VHOT, and TEMP and HOT, but not between TEMP and HOT. Each condition also elicited significantly increasing physiological strain, described by sweat rate, heart rate, physiological strain index, rating of perceived exertion and thermal sensation. Stepwise multiple regression reported rate of Trec increase and change in Trec to be predictors of increased eHsp72 concentration. Data suggests eHsp72 concentration increases once systemic temperature and sympathetic activity exceeds a minimum endogenous criteria elicited during VHOT conditions and is likely to be modulated by large, rapid changes in core temperature
Pure endoscopic endonasal odontoidectomy: anatomical study
Different disorders may produce irreducible atlanto-axial dislocation with compression of the ventral spinal cord. Among the surgical approaches available for a such condition, the transoral resection of the odontoid process is the most often used. The aim of this anatomical study is to demonstrate the possibility of an anterior cervico-medullary decompression through an endoscopic endonasal approach. Three fresh cadaver heads were used. A modified endonasal endoscopic approach was made in all cases. Endoscopic dissections were performed using a rigid endoscope, 4 mm in diameter, 18 cm in length, with 0 degree lenses. Access to the cranio-vertebral junction was possible using a lower trajectory, when compared to that necessary for the sellar region. The choana is entered and the mucosa of the rhinopharynx is dissected and transposed in the oral cavity in order to expose the cranio-vertebral junction and to obtain a mucosal flap useful for the closure. The anterior arch of the atlas and the odontoid process of C2 are removed, thus exposing the dura mater. The endoscopic endonasal approach could be a valid alternative to the transoral approach for anterior odontoidectomy
How to diagnose plantaris tendon involvement in midportion Achilles tendinopathy - clinical and imaging findings
Background: The purpose of this investigation was to evaluate if clinical assessment, Ultrasound + Colour Doppler (US + CD) and Ultrasound Tissue Characterisation (UTC) can be useful in detecting plantaris tendon involvement in patients with midportion Achilles tendinopathy. Methods: Twenty-three tendons in 18 patients (14 men, mean age: 37 years and 4 women: 44 years) (5 patients with bilateral tendons) with midportion Achilles tendinopathy were surgically treated with a scraping procedure and plantaris tendon removal. For all tendons, clinical assessment, Ultrasound + Colour Doppler (US + CD) examination and Ultrasound Tissue Characterisation (UTC) were performed. Results: At surgery, all 23 cases had a plantaris tendon located close to the medial side of the Achilles tendon. There was vascularised fat tissue in the interface between the Achilles and plantaris tendons. Clinical assessment revealed localised medial activity-related pain in 20/23 tendons and focal medial tendon tenderness in 20/23 tendons. For US + CD, 20/23 tendons had a tendon-like structure interpreted to be the plantaris tendon and localised high blood flow in close relation to the medial side of the Achilles. For UTC, 19/23 tendons had disorganised (type 3 and 4) echopixels located only in the medial part of the Achilles tendon indicating possible plantaris tendon involvement. Conclusions: US + CD directly, and clinical assessment indirectly, can detect a close by located plantaris tendon in a high proportion of patients with midportion Achilles tendinopathy. UTC could complement US + CD and clinical assessment by demonstrating disorganised focal medial Achilles tendon structure indicative of possible plantaris involvement
Auxin pretreatment promotes regeneration of sugarcane (Saccharum spp. hybrids) midrib segment explants
We have developed a new, simple,
quick and genotype-independent method for direct
regeneration of sugarcane using novel midrib
segment explants. Our protocol involves two
steps: the pretreatment of starting material on MS
(Murashige and Skoog (1962) Physiol Plant
15:473–497) medium containing 3.0 mg/l 2,4-
dichlorophenoxyacetic acid (2,4-D) for 8 days
under continuous dark and subsequent transfer of
the explants to MS medium augmented with
0.1 mg/l benzyladenine (BA) and 0.1 mg/l naphthaleneacetic
acid (NAA) under light-dark conditions.
On the regeneration medium, numerous
globular structures appeared from the explants
and subsequently differentiated into shoots.
Regenerated shoots attained 2–5 cm height
within 30 days of culture initiation and readily
rooted on MS basal medium. Hardened plants
were successfully established in the greenhouse.
The regulation of sugarcane morphogenesis by
auxin pretreatment is discussed
Changes in Present and Future Circulation Types Frequency in Northwest Iberian Peninsula
The aim of the work described herein was to study projection scenarios in order to find changes in the synoptic variability of the northwest Iberian Peninsula in the 21st century. To this end, we investigated the changes in the frequency of the different circulation types computed for the study area using three different models used in the IPCC 4th assessment report. The circulation types were computed using the procedure known as Lamb circulation types. The control simulation for the late 20th century was evaluated objectively from the results obtained using data from the NCEP/NCAR reanalysis, as to evaluate the ability of the model to reproduce the present climate. We have compared not only seasonal mean sea level pressure fields but also the mean seasonal frequency of circulation types. The results for the end of the 21st century show a decrease in the frequency of cyclonic, W, and SW circulation types in the spring and summer months. This trend also appears in the autumn, with a concomitant increase in the anticyclonic types
The search for transient astrophysical neutrino emission with IceCube-DeepCore
We present the results of a search for astrophysical sources of brief transient neutrino emission using IceCube and DeepCore data acquired between 2012 May 15 and 2013 April 30. While the search methods employed in this analysis are similar to those used in previous IceCube point source searches, the data set being examined consists of a sample of predominantly sub-TeV muon-neutrinos from the Northern Sky (-5 degrees < delta < 90 degrees) obtained through a novel event selection method. This search represents a first attempt by IceCube to identify astrophysical neutrino sources in this relatively unexplored energy range. The reconstructed direction and time of arrival of neutrino events are used to search for any significant self-correlation in the data set. The data revealed no significant source of transient neutrino emission. This result has been used to construct limits at timescales ranging from roughly 1 s to 10 days for generic soft-spectra transients. We also present limits on a specific model of neutrino emission from soft jets in core-collapse supernovae
Studying the Underlying Event in Drell-Yan and High Transverse Momentum Jet Production at the Tevatron
We study the underlying event in proton-antiproton collisions by examining
the behavior of charged particles (transverse momentum pT > 0.5 GeV/c,
pseudorapidity |\eta| < 1) produced in association with large transverse
momentum jets (~2.2 fb-1) or with Drell-Yan lepton-pairs (~2.7 fb-1) in the
Z-boson mass region (70 < M(pair) < 110 GeV/c2) as measured by CDF at 1.96 TeV
center-of-mass energy. We use the direction of the lepton-pair (in Drell-Yan
production) or the leading jet (in high-pT jet production) in each event to
define three regions of \eta-\phi space; toward, away, and transverse, where
\phi is the azimuthal scattering angle. For Drell-Yan production (excluding the
leptons) both the toward and transverse regions are very sensitive to the
underlying event. In high-pT jet production the transverse region is very
sensitive to the underlying event and is separated into a MAX and MIN
transverse region, which helps separate the hard component (initial and
final-state radiation) from the beam-beam remnant and multiple parton
interaction components of the scattering. The data are corrected to the
particle level to remove detector effects and are then compared with several
QCD Monte-Carlo models. The goal of this analysis is to provide data that can
be used to test and improve the QCD Monte-Carlo models of the underlying event
that are used to simulate hadron-hadron collisions.Comment: Submitted to Phys.Rev.
Measurement of the Production Cross Section and Search for Anomalous and Couplings in Collisions at TeV
This Letter describes the current most precise measurement of the boson
pair production cross section and most sensitive test of anomalous
and couplings in collisions at a center-of-mass energy of 1.96
TeV. The candidates are reconstructed from decays containing two charged
leptons and two neutrinos, where the charged leptons are either electrons or
muons. Using data collected by the CDF II detector from 3.6 fb of
integrated luminosity, a total of 654 candidate events are observed with an
expected background contribution of events. The measured total
cross section is pb, which is in good agreement
with the standard model prediction. The same data sample is used to place
constraints on anomalous and couplings.Comment: submitted to Phys. Rev. Let
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