425 research outputs found
Probing High Reheating Temperature Scenarios at the LHC with Long-Lived Staus
We investigate the possibility of probing high reheating temperature
scenarios at the LHC, in supersymmetric models where the gravitino is the
lightest supersymmetric particle, and the stau is the next-to-lightest
supersymmetric particle. In such scenarios, the big-bang nucleosynthesis and
the gravitino abundance give a severe upper bound on the gluino mass. We find
that, if the reheating temperature is \sim 10^8 GeV or higher, the scenarios
can be tested at the LHC with an integrated luminosity of O(1 fb^{-1}) at
\sqrt{s}=7 TeV in most of the parameter space.Comment: 17 pages, 5 figures, minor modification
Body Temperature Patterns and Rhythmicity in Free-Ranging Subterranean Damaraland Mole-Rats, Fukomys damarensis
Body temperature (Tb) is an important physiological component that affects endotherms from the cellular to whole organism level, but measurements of Tb in the field have been noticeably skewed towards heterothermic species and seasonal comparisons are largely lacking. Thus, we investigated patterns of Tb patterns in a homeothermic, free-ranging small mammal, the Damaraland mole-rat (Fukomys damarensis) during both the summer and winter. Variation in Tb was significantly greater during winter than summer, and greater among males than females. Interestingly, body mass had only a small effect on variation in Tb and there was no consistent pattern relating ambient temperature to variation in Tb. Generally speaking, it appears that variation in Tb patterns varies between seasons in much the same way as in heterothermic species, just to a lesser degree. Both cosinor analysis and Fast Fourier Transform analysis revealed substantial individual variation in Tb rhythms, even within a single colony. Some individuals had no Tb rhythms, while others appeared to exhibit multiple rhythms. These data corroborate previous laboratory work showing multiplicity of rhythms in mole-rats and suggest the variation seen in the laboratory is a true indicator of the variation seen in the wild
First experience with a new negative pressure incision management system on surgical incisions after cardiac surgery in high risk patients
<p>Abstract</p> <p>Background</p> <p>Sternal wound infection remains a serious potential complication after cardiac surgery. A recent development for preventing wound complications after surgery is the adjunctive treatment of closed incisions with negative pressure wound therapy. Suggested mechanisms of preventive action are improving the local blood flow, removing fluids and components in these fluids, helping keep the incision edges together, protecting the wound from external contamination and promoting incision healing. This work reports on our initial evaluation and clinical experience with the Prevena™Incision Management System, a recently introduced new negative pressure wound therapy system specifically developed for treating closed surgical incisions and helping prevent potential complications. We evaluated the new treatment on sternal surgical incisions in patients with multiple co-morbidities and consequently a high risk for wound complications.</p> <p>Methods</p> <p>The Prevena™incision management system was used in 10 patients with a mean Fowler risk score of 15.1 [Range 8-30]. The negative pressure dressing was applied immediately after surgery and left in place for 5 days with a continuous application of -125 mmHg negative pressure. Wounds and surrounding skin were inspected immediately after removal of the Prevena™ incision management system and at day 30 after surgery.</p> <p>Results</p> <p>Wounds and surrounding skin showed complete wound healing with the absence of skin lesions due to the negative pressure after removal of the Prevena™ dressing. No device-related complications were observed. No wound complications occurred in this high risk group of patients until at least 30 days after surgery.</p> <p>Conclusions</p> <p>The Prevena™system appears to be safe, easy to use and may help achieve uncomplicated wound healing in patients at risk of developing wound complications after cardiothoracic surgery.</p
Brain perfusion imaging with voxel-based analysis in secondary progressive multiple sclerosis patients with a moderate to severe stage of disease: a boon for the workforce
Background: The present study was carried out to evaluate cerebral perfusion in multiple sclerosis (MS) patients
with a moderate to severe stage of disease. Some patients underwent hyperbaric oxygen therapy (HBOT) and brain
perfusion between before and after that was compared.
Methods: We retrospectively reviewed 25 secondary progressive (SP)-MS patients from the hospital database.
Neurological disability evaluated by Expanded Disability Status Scale Score (EDSS). Brain perfusion was performed
by (99 m) Tc-labeled bicisate (ECD) brain SPECT and the data were compared using statistical parametric mapping
(SPM). In total, 16 patients underwent HBOT. Before HBOT and at the end of 20 sessions of oxygen treatment,
99mTc-ECD brain perfusion single photon emission computed tomography (SPECT) was performed again then
the results were evaluated and compared. Brain perfusion was performed by (99 m) Tc-labeled bicisate (ECD) brain
SPECT and the data were compared using statistical parametric mapping (SPM).
Results: A total of 25 SP-MS patients, 14 females (56 %) and 11 males (44 %) with a mean age of 38.92 ± 11.
28 years included in the study. The mean disease duration was 8.70 ± 5.30 years. Of the 25 patients, 2 (8 %) had
a normal SPECT and 23 (92 %) had abnormal brain perfusion SPECT studies. The study showed a significant
association between severity of perfusion impairment with disease duration and also with EDSS (P <0.05). There
was a significant improvement in pre- and post-treatment perfusion scans (P <0.05), but this did not demonstrate
a significant improvement in the clinical subjective and objective evaluation of patients (P >0.05).
Conclusions: This study depicted decreased cerebral perfusion in SP-MS patients with a moderate to severe
disability score and its association with clinical parameters. Because of its accessibility, rather low price, practical
ease, and being objective quantitative information, brain perfusion SPECT can be complementing to other
diagnostic modalities such as MRI and clinical examinations in disease surveillance and monitoring. The literature
on this important issue is extremely scarce, and follow up studies are required to assess these preliminary results
Physics, Astrophysics and Cosmology with Gravitational Waves
Gravitational wave detectors are already operating at interesting sensitivity
levels, and they have an upgrade path that should result in secure detections
by 2014. We review the physics of gravitational waves, how they interact with
detectors (bars and interferometers), and how these detectors operate. We study
the most likely sources of gravitational waves and review the data analysis
methods that are used to extract their signals from detector noise. Then we
consider the consequences of gravitational wave detections and observations for
physics, astrophysics, and cosmology.Comment: 137 pages, 16 figures, Published version
<http://www.livingreviews.org/lrr-2009-2
Networked learning, stepping beyond the net generation and digital natives
This chapter critically examines the idea that young people have undergone a change in which exposure to digital and networked technologies has caused a step change in the character of a whole generation. The empirical and theoretical basis for this argument is reviewed and critical theoretical perspectives are assessed. Evidence from earlier research is compared and contrasted with evidence gathered from students who are said to be part of the new generation. The chapter explores the consequences of these ideas from the standpoint of networked learning. One aim of the chapter is to suggest ways in which the changes that have taken can be more adequately theorized in relation to the idea of networked learning. Arguments used to support generational change rely on a technological determinism and alternative accounts understand young people as active agents. I suggest ex-panding the notion of the agent to include persons enacting roles in collective or-ganizations. Overall the importance of the debate is that determinist arguments can close down debate and networked learning would be impoverished if this occurs
Ocorrência de Trichospilus diatraeae (Hym.: Eulophidae) em broca-das-cucurbitáceas, no Brasil
Altered intercellular communication in lung fibroblast cultures from patients with idiopathic pulmonary fibrosis
RATIONALE: Gap junctions are membrane channels formed by an array of connexins which links adjacent cells realizing an electro- metabolic synapse. Connexin-mediated communication is crucial in the regulation of cell growth, differentiation, and development. The activation and proliferation of phenotypically altered fibroblasts are central events in the pathogenesis of idiopathic pulmonary fibrosis. We sought to evaluate the role of connexin-43, the most abundant gap-junction subunit in the human lung, in the pathogenesis of this condition. METHODS: We investigated the transcription and protein expression of connexin-43 and the gap-junctional intercellular communication (GJIC) in 5 primary lung fibroblast lines derived from normal subjects (NF) and from 3 histologically proven IPF patients (FF). RESULTS: Here we show that connexin-43 mRNA was significantly reduced in FF as demonstrated by standard and quantitative RT-PCR. GJIC was functionally evaluated by means of flow-cytometry. In order to demonstrate that dye spreading was taking place through gap junctions, we used carbenoxolone as a pharmacological gap-junction blocker. Carbenoxolone specifically blocked GJIC in our system in a concentration dependent manner. FF showed a significantly reduced homologous GJIC compared to NF. Similarly, GJIC was significantly impaired in FF when a heterologous NF line was used as dye donor, suggesting a complete defect in GJIC of FF. CONCLUSION: These results suggest a novel alteration in primary lung fibroblasts from IPF patients. The reduced Cx43 expression and the associated alteration in cell-to-cell communication may justify some of the known pathological characteristic of this devastating disease that still represents a challenge to the medical practice
Validity and reliability of the Foot Function Index (FFI) questionnaire Brazilian-Portuguese version
- …