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81.
Jorge Barrios-Muriel Francisco Romero Sánchez Francisco Javier Alonso Sánchez David Rodríguez Salgado 《Computer methods in biomechanics and biomedical engineering》2013,16(15):1219-1228
AbstractWhen designing any rehabilitation, sportswear or exoskeleton device the mechanical behaviour of the body segment must be known, specifically the skin, because an excessive tissue strain may lead to ulceration and bedsores. To date, it is not known if the kinematic variability between subjects have an effect on the skin strain field, and therefore, in the design and manufacturing of rehabilitation products, such as orthoses. Several studies have analysed the skin deformation during human motion, nevertheless, the comparison between the skin strain field in different subjects during normal or pathological gait has not been reported yet. This work presents a comparison of skin strain analysis for different gait patterns to study the differences between people and, specifically, if it is possible to standardize the orthotic design between subjects with the same gait disorder. Moreover, the areas with relatively minimum strain during the ankle-foot motion are compared to improve the design of structural parts of rehabilitation devices. In this case, a validated 3D digital image correlation system has been used for this purpose combined with strain ellipse theory. The results demonstrate variations in the skin strain field between subjects with the same pathology and similarities between subjects with normal gait. However, more studies and experiments are necessaries to validate this hypothesis and also to test it between different gait pathologies. 相似文献
82.
Robert de Bruijn L. Michael Romero 《Comparative biochemistry and physiology. Part A, Molecular & integrative physiology》2013,164(3):512-519
Free-roaming animals continually cope with changes in their environment. One of the most unpredictable environmental phenomena is weather. Being able to respond to weather appropriately is crucial as it can be a threat to survival. The stress response, consisting of increases in heart rate and release of glucocorticoids, is an important mechanism by which animals cope with stressors. This study examined behavioral, heart rate, and corticosterone responses of captive European starlings (Sturnus vulgaris) to two aspects of weather mimicked under controlled conditions, a subtle (3 °C) decrease in temperature and a short, mild bout of rain. Both decreased temperature and exposure to rain elicited increases in heart rate and corticosterone in non-molting starlings. Molt is an important life history stage in birds that affects feather cover and may require a different response to weather-related stressors. We repeated the experiment in molting starlings and found increases in heart rate in response to rain and cold wind. However, the hypothalamic–pituitary–adrenal (HPA)-axis was suppressed during molt, as molting starlings did not increase corticosterone release in response to either stimulus. These data suggest these stimuli induce increased allostatic load in starlings, and that animals may adjust their response depending on the life-history stage. 相似文献
83.
Jaime Gomez-Millan Jesús Romero Fernández Jose Antonio Medina Carmona 《Reports of Practical Oncology and Radiotherapy》2013,18(6):371-375
Background
IMRT provides highly conformal dose distributions creating non uniform spatial intensity using different segments in the beam.Material & Methods and Results
Different retrospective studies have shown a high capability of IMRT to treat tumours close to the base of skull. Prospective studies have shown a decrease in xerostomia compared with conventional 3D conformal treatment (3DCRT). Modulation of intensity is performed by the movement of the multileaf collimator (MLC) that can deliver the radiation in different ways, such as static field segments, dynamic field segments and rotational delivery (arc therapy and tomotherapy). There are slight differences among the different techniques in terms of homogeneity, dose conformity and treatment delivery time.Conclusions
The best method to deliver IMRT will depend on multiple factors such as deliverability, practicality, user training and plan quality. 相似文献84.
Andrew E. Schuh Thomas Lauvaux Tristram O. West A. Scott Denning Kenneth J. Davis Natasha Miles Scott Richardson Marek Uliasz Erandathie Lokupitiya Daniel Cooley Arlyn Andrews Stephen Ogle 《Global Change Biology》2013,19(5):1424-1439
An intensive regional research campaign was conducted by the North American Carbon Program (NACP) in 2007 to study the carbon cycle of the highly productive agricultural regions of the Midwestern United States. Forty‐five different associated projects were conducted across five US agencies over the course of nearly a decade involving hundreds of researchers. One of the primary objectives of the intensive campaign was to investigate the ability of atmospheric inversion techniques to use highly calibrated CO2 mixing ratio data to estimate CO2 flux over the major croplands of the United States by comparing the results to an inventory of CO2 fluxes. Statistics from densely monitored crop production, consisting primarily of corn and soybeans, provided the backbone of a well studied bottom‐up inventory flux estimate that was used to evaluate the atmospheric inversion results. Estimates were compared to the inventory from three different inversion systems, representing spatial scales varying from high resolution mesoscale (PSU), to continental (CSU) and global (CarbonTracker), coupled to different transport models and optimization techniques. The inversion‐based mean CO2‐C sink estimates were generally slightly larger, 8–20% for PSU, 10–20% for CSU, and 21% for CarbonTracker, but statistically indistinguishable, from the inventory estimate of 135 TgC. While the comparisons show that the MCI region‐wide C sink is robust across inversion system and spatial scale, only the continental and mesoscale inversions were able to reproduce the spatial patterns within the region. In general, the results demonstrate that inversions can recover CO2 fluxes at sub‐regional scales with a relatively high density of CO2 observations and adequate information on atmospheric transport in the region. 相似文献
85.
R. Albajes C. Cantero-Martínez T. Capell P. Christou A. Farre J. Galceran F. López-Gatius S. Marin O. Martín-Belloso Ma.-J. Motilva C. Nogareda J. Peman J. Puy J. Recasens I. Romagosa Ma.-P. Romero V. Sanchis R. Savin G. A. Slafer R. Soliva-Fortuny I. Viñas J. Voltas 《Molecular breeding : new strategies in plant improvement》2013,32(4):743-770
The food production and processing value chain is under pressure from all sides—increasing demand driven by a growing and more affluent population; dwindling resources caused by urbanization, land erosion, pollution and competing agriculture such as biofuels; and increasing constraints on production methods driven by consumers and regulators demanding higher quality, reduced chemical use, and most of all environmentally beneficial practices ‘from farm to fork’. This pressure can only be addressed by developing efficient and sustainable agricultural practices that are harmonized throughout the value chain, so that renewable resources can be exploited without damaging the environment. Bridges must, therefore, be built between the diverse areas within the food production and processing value chain, including bridges between different stages of production, between currently unlinked agronomic practices, and between the different levels and areas of research to achieve joined-up thinking within the industry, so that the wider impact of different technologies, practices and materials on productivity and sustainability is understood at the local, regional, national and global scales. In this article, we consider the challenges at different stages and levels of the value chain and how new technologies and strategies could be used to build bridges and achieve more sustainable food/feed production in the future. 相似文献
86.
87.
Physicochemical Characterization of a Thermostable Alcohol Dehydrogenase from Pyrobaculum aerophilum
Annalisa Vitale Natasha Thorne Scott Lovell Kevin P. Battaile Xin Hu Min Shen Sabato D'Auria Douglas S. Auld 《PloS one》2013,8(6)
In this work we characterize an alcohol dehydrogenase (ADH) from the hyperthermophilic archaeon Pyrobaculum aerophilum (PyAeADHII). We have previously found that PyAeADHII has no activity when standard ADH substrates are used but is active when α-tetralone is used as substrate. Here, to gain insights into enzyme function, we screened several chemical libraries for enzymatic modulators using an assay employing α-tetralone. The results indicate that PyAeADHII activity in the presence of α-tetralone was inhibited by compounds such as flunarizine. We also examined metal coordination of the enzyme in solution by performing metal substitution of the enzyme-bound zinc (Zn2+) with cobalt. The solution-based absorption spectra for cobalt substituted PyAeADHII supports substitution at the structural Zn2+ site. To gain structural insight, we obtained the crystal structure of both wild-type and cobalt-substituted PyAeADHII at 1.75 Å and 2.20 Å resolution, respectively. The X-ray data confirmed one metal ion per monomer present only at the structural site with otherwise close conservation to other ADH enzymes. We next determined the co-crystal structure of the NADPH-bound form of the enzyme at 2.35 Å resolution to help define the active site region of the enzyme and this data shows close structural conservation with horse ADH, despite the lack of a catalytic Zn2+ ion in PyAeADHII. Modeling of α-tetralone into the NADPH bound structure suggests an arginine as a possible catalytic residue. The data presented here can yield a better understanding of alcohol dehydrogenases lacking the catalytic zinc as well as the structural features inherent to thermostable enzymes. 相似文献
88.
Julio Plaza-Diaz Carolina Gomez-Llorente Laura Campa?a-Martin Esther Matencio Inmaculada Ortu?o Rosario Martínez-Silla Carlos Gomez-Gallego Maria Jesús Periago Gaspar Ros Empar Chenoll Salvador Genovés Beatriz Casinos ángela Silva Dolores Corella Olga Portolés Fernando Romero Daniel Ramón Antonio Perez de la Cruz Angel Gil Luis Fontana 《PloS one》2013,8(10)
We previously described the isolation and characterization of three probiotic strains from the feces of exclusively breast-fed newborn infants: Lactobacillus paracasei CNCM I-4034, Bifidobacterium breve CNCM I-4035 and Lactobacillus rhamnosus CNCM I-4036. These strains were shown to adhere to intestinal mucus in vitro, to be sensitive to antibiotics and to resist biliary salts and low pH. In the present study, a multicenter, randomized, double-blind, placebo-controlled trial with 100 healthy volunteers in three Spanish cities was carried out to evaluate the tolerance, safety, gut colonization and immunomodulatory effects of these three probiotics. Volunteers underwent a 15-day washout period, after which they were randomly divided into 5 groups that received daily a placebo, a capsule containing one of the 3 strains or a capsule containing a mixture of two strains for 30 days. The intervention was followed by another 15-day washout period. Patients did not consume fermented milk for the entire duration of the study. Gastrointestinal symptoms, defecation frequency and stool consistency were not altered by probiotic intake. No relevant changes in blood and serum, as well as no adverse events occurred during or after treatment. Probiotic administration slightly modified bacterial populations in the volunteers’ feces. Intestinal persistence occurred in volunteers who received L. rhamnosus CNCM I-4036. Administration of B. breve CNCM I-4035 resulted in a significant increase in fecal secretory IgA content. IL-4 and IL-10 increased, whereas IL-12 decreased in the serum of volunteers treated with any of the three strains. These results demonstrate that the consumption of these three bacterial strains was safe and exerted varying degrees of immunomodulatory effects.
Trial Registration
ClinicalTrials.gov NCT01479543 相似文献89.
90.