4,439 research outputs found
INFLUENCE OF MIDSOLE CONSTRUCTION AND UPPER VAMP DESIGN IN THE PRONATION MOVEMENT WHILE RUNNING
The relationship between the excessive rearfoot pronation and some injuries has been widely described in the literature (Bates, Cavanagh, Nigg, Stacoff). The influence of midsole design and material in the amount of pronation has also been analyzed by different authors. Nevertheless the relative influence of midsole and upper vamp design and their interactions have not been studied enough. The aim of the study presented was to investigate the relative effect of midsole material and thickness as well as upper vamp systems in controlling pronation. Twelve prototypes of running shoes were specially designed and constructed for this study. The prototypes corresponded to a factorial experiment design of the following factors: two midsole thicknesses, three midsole materials, and the presence or absence of an external heel counter and post. The materials selection was based on a previous study of the mechanical characteristics of a group of different Poliurethanes with different densities. The stiffness and energy absorbing capacity of the materials were previously studied by simulating impact loads of running by means of a dynamic testing machine. The external heel counter and post was selected as a representative of a very effective rearfoot control feature based in a previous study where it appeared to be the most effective system of the studied (heel counters, bondings for the lacing and internal posts). Three runners participated in the study. All of them were rearfoot strikers and hiperpronators. The experiences consisted of filming three right foot supports with two high speed cameras. Velocity of running was fixed at 12.8 Km per hour while velocity of filmation was fixed at 150 images per second. After digitizing the images obtained, a three dimensional study of the rearfoot movement was done. The results obtained can be summarized as follows: - Midsole thickness, midsole material and the presence of the heel counter showed significant influence on maximum rearfoot pronation with the most important being the midsole material in the range of variations of the study. - The material presenting low rigidity and low shock absorbing capacity was the one that showed higher pronation angles. - Higher pronation angles were found for the thicker midsoles. - The heel counter and post was found to have less influence on maximum pronation angles than the midsole thickness and material
Hallazgos neurorradiológicos de la Acidosis Glutárica tipo I
Glutaric aciduria type I is a rare disorder of organic acid metabolism caused by
deficiency of glutaryl-CoA dehydrogenase, a mitochondrial enzyme. Improper
degeneration of amino acids: tryptophan, lysine, and hydroxylysine, results in
increased levels of glutaric acid, which typically becomes clinically manifest as
an acute dystonic crisis in young children. Accumulation of glutaric acid causes
neurotoxicity in the basal ganglia and fronto-temporal cortex which can lead to
progressive dystonia, hypotonia, permanently impaired speech and seizures.
Because dietary and drug therapy may alter the natural history of the disease,
early diagnosis of such patients is critical. We report the magnetic resonance
(MR) imaging findings in a 16 year-old girl with this disorder who presented with
a chronic dystonic syndrome and previously diagnosed of brain paralysis. MR
imaging demonstrated bilateral involvement of the putamina and periventricular
white matter, and bilateral temporal atrophy and widened Silvian fissure
Agricultural productivity in past societies: toward an empirically informed model for testing cultural evolutionary hypotheses
Agricultural productivity, and its variation in space and time, plays a fundamental role in many theories of human social evolution. However, we often lack systematic information about the productivity of past agricultural systems on a scale large enough to test these theories properly. The effect of climate on crop yields has received a great deal of attention resulting in a range of empirical and process-based models, yet the focus has primarily been on current or future conditions. In this paper, we argue for a “bottom-up” approach that estimates potential productivity based on information about the agricultural practices and technologies used in past societies. Of key theoretical interest is using this information to estimate the carrying high quality historical and archaeological information about past societies in order to infer the temporal and geographic patterns of change in agricultural productivity and potential. We discuss information we need to collect about past agricultural techniques and practices, and introduce a new databank initiative that we have developed for collating the best available historical and archaeological evidence. A key benefit of our approach lies in making explicit the steps in the estimation of past productivities and carrying capacities, and in being able to assess the effects of different modelling assumptions. This is undoubtedly an ambitious task, yet promises to provide important insights into fundamental aspects of past societies, enabling us to test more rigorously key hypotheses about human socio-cultural evolution
Atypical carcinoid tumours of the lung: prognostic factors and patterns of recurrence
Background: Atypical carcinoids (AC) of the lung are rare intermediate-grade neuroendocrine neoplasms. Prognostic factors for these tumours are undefined. Methods: Our cooperative group retrieved data on 127 patients operated between 1980 and 2009 because of an AC. Several clinical and pathological features were studied. Results: In a univariable analysis, T-status (p=0.005), N-status (p=0.021), preoperative M-status (previously treated) (p=0.04), and distant recurrence developed during the outcome (p<0.001) presented statistically significant differences related to survival of these patients. In a multivariable analysis, only distant recurrence was demonstrated to be an independent risk factor for survival (p<0.001; HR: 13.1). During the monitoring, 25.2% of the patients presented some kind of recurrence. When we studied recurrence factors in a univariable manner, sublobar resections presented significant relationship with locoregional recurrence (p<0.001). In the case of distant recurrence, T and N status presented significant differences. Patients with preoperative M1 status presented higher frequencies of locoregional and distant recurrence (p=0.004 and p<0.001, respectively). In a multivariable analysis, sublobar resection was an independent prognostic factor to predict locoregional recurrence (p=0.002; HR: 18.1). Conclusions: Complete standard surgical resection with radical lymphadenectomy is essential for AC. Sublobar resections are related to locoregional recurrence, so they should be avoided except for carefully selected patients. Nodal status is an important prognostic factor to predict survival and recurrence. Distant recurrence is related to poor outcome
New symmetrical quinazoline derivatives selectively induce apoptosis in human cancer cells
In the search of new symmetrical derivatives with anticancer activity, we have looked for novel compounds able to induce a selective proapoptotic mechanism in cancer cells. The potential antitumoral activity of several quinazoline derivatives was evaluated in vitro examining their cytotoxic effects against human breast, colon and bladder cancer cell lines. The IC(50) value of the compounds that showed cytotoxic activity was calculated. These compounds were tested for their ability to induce caspase-3 activation and nuclear chromatin degradation. Non-tumoral human cell lines were used to test the selectivity of the cytotoxic compounds against cancer cells. Several compounds showed no cytotoxicity in these cell lines. Finally, JRF12 (2,4-dibenzylaminoquinazoline) was chosen as the best candidate and its mechanism of action was studied in more detail. A time dependent evaluation of apoptosis was performed in the three cancer cell lines, followed by an evaluation of the cell cycle regulation involvement that showed a decrease of cells in G(1) phase and increase of cells in G(2) phase before cell death. 2,4-dibenzylaminoquinazoline treatment produces few changes in the expression of genes as evaluated by using oligonucleotide microarrays and Q-RT-PCR assays. In conclusion, 2,4-dibenzylaminoquinazoline is a promising anticancer drug showing cytostatic and apoptotic effects mainly in a transcription independent manner
Pseudopotential study of binding properties of solids within generalized gradient approximations: The role of core-valence exchange-correlation
In ab initio pseudopotential calculations within density-functional theory
the nonlinear exchange-correlation interaction between valence and core
electrons is often treated linearly through the pseudopotential. We discuss the
accuracy and limitations of this approximation regarding a comparison of the
local density approximation (LDA) and generalized gradient approximations
(GGA), which we find to describe core-valence exchange-correlation markedly
different. (1) Evaluating the binding properties of a number of typical solids
we demonstrate that the pseudopotential approach and namely the linearization
of core-valence exchange-correlation are both accurate and limited in the same
way in GGA as in LDA. (2) Examining the practice to carry out GGA calculations
using pseudopotentials derived within LDA we show that the ensuing results
differ significantly from those obtained using pseudopotentials derived within
GGA. As principal source of these differences we identify the distinct behavior
of core-valence exchange-correlation in LDA and GGA which, accordingly,
contributes substantially to the GGA induced changes of calculated binding
properties.Comment: 13 pages, 6 figures, submitted to Phys. Rev. B, other related
publications can be found at http://www.rz-berlin.mpg.de/th/paper.htm
Impact of renal retransplantation on graft and recipient survival
The aim of this study was to evaluate the influence of
retransplantation in graft and recipient survival. METHODS: We carried out a
retrospective study in 419 renal transplants and studied the influence of
retransplantation in graft and patient survival. A homogeneity study was
performed between the two groups with a Student`s T and a chi-square tests. Graft
survival analysis was performed with Kaplan-Meyer and log rank tests. RESULTS: Of
419 transplants, 370 (88.3%) were first transplantations, 45 (10.7%) second
transplantations and 4(1%) third ones. Mean follow-up of the whole group was 72.5
months (+/-54.1 SD). There were no differences in follow-up between groups (Mean
Follow-up 73.1 months +/-54.4 SD in first transplantations vs. 61.6 months
+/-51.2 SD in repeat transplantation. p >0.05). The actuarial graft survival
showed no differences between patients with first transplantation and those with
a repeat one. [3 and 5 year SV of 89% (95% CI: 87-91%) and 84%(95% CI: 82-86%) Vs
88% (95% CI; 83-93%) and 85% (95% CI:i; 80-90%) respectively]. After adjusting
for all the heterogeneity variables we still did not find differences on graft
survival. The actuarial recipient survival showed no differences between patients
with first transplantation and those with a repeat one. [3 and 5 year SV of 98%
and 96% Vs.97%]. CONCLUSIONS: There are no differences of graft and recipient
survival between patients with a first transplantation and those with a repeat
one
Towards Inflation in String Theory
We investigate the embedding of brane inflation into stable compactifications
of string theory. At first sight a warped compactification geometry seems to
produce a naturally flat inflaton potential, evading one well-known difficulty
of brane-antibrane scenarios. Careful consideration of the closed string moduli
reveals a further obstacle: superpotential stabilization of the
compactification volume typically modifies the inflaton potential and renders
it too steep for inflation. We discuss the non-generic conditions under which
this problem does not arise. We conclude that brane inflation models can only
work if restrictive assumptions about the method of volume stabilization, the
warping of the internal space, and the source of inflationary energy are
satisfied. We argue that this may not be a real problem, given the large range
of available fluxes and background geometries in string theory.Comment: 41 pages, harvmac; v2: results of appendix A extended to include
branes at angles, typos corrected, refs adde
Grade V small bowel injury after blunt abdominal trauma: a case report
Injury of the small intestine or mesentery that requires surgical intervention is relatively uncommon, presenting less than 1% of all trauma. Unstable hemodynamically patients with peritoneal irritation signs and stable hemodynamically patients with radiological signs of intestine or mesentery lesions need an exploratory laparotomy. A 33-year-old male patient, suffered a car accident in which he had a frontal impact collision and was between two structures for 30 minutes, and rescued by the fire department. Physical examination of the abdomen presents generalized pain on palpation of moderate intensity and rebound sign. An exploratory laparotomy was performed, the findings were: hemoperitoneum of 1500 ml was found, lesion in the bucket loop of 1.2 meters, 1.8 meters from the Treitz angle and 70 cm from the ileocecal valve. We managed with drainage, vascular control, resection of the devascularized intestinal loop and small bowel shotgun stoma were. The patient was transferred to the intensive care unit for hemodynamic management and a second look was performed 5 days after surgery where cavity lavage, stoma dismantling and end-to-end anastomosis of the small intestine in two planes were performed. On post-operative day 7 drains were removed, and the patient was discharged from the surgical service due to improvement, without complications. We recommend a multidisciplinary approach to patients with polytrauma, since they lead to a better and faster recovery, in the same way it allows us to detect and treat any abnormality that impacts the quality of life of patients early
Oncologist’s knowledge and implementation of guidelines for breakthrough cancer pain in Spain: CONOCE study
[Purpose]: Breakthrough cancer pain (BTcP) has been shown to be a prevalent and poor prognostic factor for oncologic patients, which remain under diagnosed and undertreated. In 2012, the Spanish Society of Medical Oncology (SEOM) published a clinical practice guideline (CPG) for the treatment of cancer pain which specifically addressed the management of BTcP.[Methods]: Fundación ECO designed a qualitative study using an Internet-based survey to investigate the attitudes toward, compliance with, and use of SEOM Guideline.[Results]: A total of 83 oncologists with a mean experience of 13 years responded. Overall, 82% were aware of different guidelines to manage BTcP. Notably, attitudes toward guidelines were highly positive and there was nearly unanimous agreement that CPG provided the best scientific evidence available (99%), on the minimum information to be gathered for the medical history (100%), on the need for a specific treatment for BTcP (100%), and fentanyl as the first-choice drug (99%). Interestingly, there were discrepancies between what oncologists agreed with and what they do in clinical practice. In fact, 87.6% declare full compliance with SEOM guideline, although adherence to registration of BTcP data in medical records ranged from 30.1 to 91.6% (mean 64.5%); therapeutic management compliance was higher ranging from 75.9 to 91.6%. Main barriers identified were time pressure together with vague statements and limited dissemination of the guidelines.[Conclusion]: Despite oncologist’s clinical practice is increasingly guided by GPC, it suffers from limited compliance, at least in part due to suboptimal statements. Improved dissemination and education are needed to enhance guideline implementation.This study was funded by Kyowa Kirin Farmacéutica S. L.U. through Fundación ECO
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