132 research outputs found
Using Heavy Quark Spin Symmetry in Semileptonic Decays
The form factors parameterizing the B_c semileptonic matrix elements can be
related to a few invariant functions if the decoupling of the spin of the heavy
quarks in B_c and in the mesons produced in the semileptonic decays is
exploited. We compute the form factors as overlap integral of the meson
wave-functions obtained using a QCD relativistic potential model, and give
predictions for semileptonic and non-leptonic B_c decay modes. We also discuss
possible experimental tests of the heavy quark spin symmetry in B_c decays.Comment: RevTex, 22 pages, 2 figure
An internet-based intervention for depression in primary care in Spain: A randomized controlled trial
Background: Depression is the most prevalent cause of illness-induced disability worldwide. Face-to-face psychotherapeutic interventions for depression can be challenging, so there is a need for other alternatives that allow these interventions to be offered. One feasible alternative is Internet-based psychological interventions. This is the first randomized controlled trial (RCT) on the effectiveness of an Internet-based intervention on depression in primary health care in Spain. Objective: Our aim was to compare the effectiveness of a low-intensity therapist-guided (LITG) Internet-based program and a completely self-guided (CSG) Internet-based program with improved treatment as usual (iTAU) care for depression. Methods: Multicenter, three-arm, parallel, RCT design, carried out between November 2012 and January 2014, with a follow-up of 15 months. In total, 296 adults from primary care settings in four Spanish regions, with mild or moderate major depression, were randomized to LITG (n=96), CSG (n=98), or iTAU (n=102). Research completers at follow-up were 63.5%. The intervention was Smiling is Fun, an Internet program based on cognitive behavioral therapy. All patients received iTAU by their general practitioners. Moreover, LITG received Smiling is Fun and the possibility of psychotherapeutic support on request by email, whereas CSG received only Smiling is Fun. The main outcome was the Beck Depression Inventory-II at 3 months from baseline. Mixed-effects multilevel analysis for repeated measures were undertaken. Results: There was no benefit for either CSG (B coefficient=-1.15; P=.444)] or LITG (B=-0.71; P=.634)] compared to iTAU, at 3 months. There were differences at 6 months iTAU vs CSG (B=-4.22; P=.007); iTAU vs LITG (B=-4.34; P=.005)] and 15 months iTAU vs CSG (B=-5.10; P=.001); iTAU vs LITG (B=-4.62; P=.002)]. There were no differences between CSG and LITG at any time. Adjusted and intention-to-treat models confirmed these findings. Conclusions: An Internet-based intervention for depression combined with iTAU conferred a benefit over iTAU alone in the Spanish primary health care system
Radioprotectors and Mitigators of Radiation-Induced Normal Tissue Injury
The article reviews agents in clinical use or in development as radioprotectors and mitigators of radiation-induced normal tissue injury
Bone Marrow-Derived Cells Implanted into Radiation-Injured Urinary Bladders Reconstruct Functional Bladder Tissues in Rats
The purpose of this study was to determine whether bone marrow-derived cells implanted into radiation-injured urinary bladders could reconstruct functional bladder tissues. The pelvic region of anesthetized female Sprague-Dawley (SD) rats was irradiated with 2 Gy once a week for 5 weeks. After the last irradiation, the rats were maintained for 2 weeks. Bone marrow cells were harvested from the femurs of donor male green fluorescence protein (GFP)-transfected SD rats and cultured for 7 days. Two weeks after the last radiation exposure, the cultured adherent, proliferating bone marrow-derived cells were implanted into the walls of irradiated urinary bladders. For controls, cell-free solutions were similarly injected. Four weeks after donor cell or control implantations, cystometric, histological, and immunohistochemical investigations were performed. Two weeks after the last irradiation, the smooth muscle layers and nerve fibers of the irradiated urinary bladders were disorganized. The proportions of smooth muscle layer and nerve fiber areas were significantly decreased compared with sham-irradiated urinary bladders. In addition, the remaining smooth muscle cells within the irradiated urinary bladders expressed P4HB, an indicator of collagen synthesis. In the cystometric investigations, the voiding interval of irradiated rats was irregularly prolonged, 7.92 +/- 1.09 min, and the residual volume, 0.13 +/- 0.03 mL, was significantly higher compared with the sham-irradiated rats (5.50 +/- 0.43mL and 0.05 +/- 0.01 mL). After 4 weeks, the smooth muscle layers and nerve fibers in the cell-free control urinary bladders remained similar to the pre-implanted irradiated urinary bladders; however, the cell-implanted urinary bladders contained reconstructed smooth muscle layers and nerve fibers, the proportions of each were significantly higher than those in the cell-free injected controls. The expression of P4HB within the cell-implanted urinary bladders decreased. Some GFP-positive implanted cells differentiated into smooth muscle-and nerve-like cells and became organized into the reconstructed tissues. The voiding interval of the cell-implanted rats, 5.46 +/- 0.33 min, was regular and similar to that of the sham-irradiated rats, and significantly less than that of the cell-free injected controls, 7.39 +/- 0.54 min. The residual volume, 0.04 +/- 0.01 mL, was similar to that of the sham-irradiated rats and significantly decreased compared with that of the cell-free injected controls, 0.15 +/- 0.05 mL. Therefore, the implantation of bone marrow-derived cells is a potentially useful treatment for radiotherapy-induced urinary dysfunctions.ArticleTISSUE ENGINEERING PART A. 18(15-16):1698-1709 (2012)journal articl
A meta-analysis of hyperfractionated and accelerated radiotherapy and combined chemotherapy and radiotherapy regimens in unresected locally advanced squamous cell carcinoma of the head and neck
BACKGROUND: Former meta-analyses have shown a survival benefit for the addition of chemotherapy (CHX) to radiotherapy (RT) and to some extent also for the use of hyperfractionated radiation therapy (HFRT) and accelerated radiation therapy (AFRT) in locally advanced squamous cell carcinoma (SCC) of the head and neck. However, the publication of new studies and the fact that many older studies that were included in these former meta-analyses used obsolete radiation doses, CHX schedules or study designs prompted us to carry out a new analysis using strict inclusion criteria. METHODS: Randomised trials testing curatively intended RT (≥60 Gy in >4 weeks/>50 Gy in <4 weeks) on SCC of the oral cavity, oropharynx, hypopharynx, and larynx published as full paper or in abstract form between 1975 and 2003 were eligible. Trials comparing RT alone with concurrent or alternating chemoradiation (5-fluorouracil (5-FU), cisplatin, carboplatin, mitomycin C) were analyzed according to the employed radiation schedule and the used CHX regimen. Studies comparing conventionally fractionated radiotherapy (CFRT) with either HFRT or AFRT without CHX were separately examined. End point of the meta-analysis was overall survival. RESULTS: Thirty-two trials with a total of 10 225 patients were included into the meta-analysis. An overall survival benefit of 12.0 months was observed for the addition of simultaneous CHX to either CFRT or HFRT/AFRT (p < 0.001). Separate analyses by cytostatic drug indicate a prolongation of survival of 24.0 months, 16.8 months, 6.7 months, and 4.0 months, respectively, for the simultaneous administration of 5-FU, cisplatin-based, carboplatin-based, and mitomycin C-based CHX to RT (each p < 0.01). Whereas no significant gain in overall survival was observed for AFRT in comparison to CFRT, a substantial prolongation of median survival (14.2 months, p < 0.001) was seen for HFRT compared to CFRT (both without CHX). CONCLUSION: RT combined with simultaneous 5-FU, cisplatin, carboplatin, and mitomycin C as single drug or combinations of 5-FU with one of the other drugs results in a large survival advantage irrespective the employed radiation schedule. If radiation therapy is used as single modality, hyperfractionation leads to a significant improvement of overall survival. Accelerated radiation therapy alone, especially when given as split course radiation schedule or extremely accelerated treatments with decreased total dose, does not increase overall survival
Late Pleistocene fossils and the future distribution of Rana temporaria (Amphibia, Anura) along the Apennine Peninsula (Italy)
Feature correspondence and motion recovery in vehicle planar navigation
Abstract This paper describes a strategy to feature point correspondence and motion recovery in vehicle navigation. A transformation of the image plane is proposed that keeps the motion of the vehicle on a plane parallel to the transformed image plane. This permits to de"ne linear tracking "lters to estimate the real-world positions of the features, and allows us to select the matches that accomplish the rigidity of the scene by a Hough transform. Candidate correspondences are selected by similarity, taking into account the smoothness of motion. Further processing brings out the "nal matching. The methods have been tested in a real application
Un Nou discoglòssid "(Amphibia: Anura)" de l'Holocè de Menorca
Some fossil remains of a new discolglossid species, Baleaphryne talaioticus, from the Holocene site Rafal Rubi (Minorca), are described in this article. This species is quite similar to the only other known in the genus (B. Muletensis, from Majorca). The B. Talaioticus humeri are somewhat shorter and more robust than those of B. Muletensis, representing
this incipient digging adaptation either a parallel trend with respect to the Alytes one, or else an evolutionary reversal in Baleaphryne towards less specialized morphologies. Other Minorcan remains from the 11 Century b.C. are referred to B. Talaioticus, suggesting that the species might still be alive.Se describen los restos de una nueva especie de discoglósido, Baleaphryne talaioticus, procedente del yacimiento holocénico de Rafal Rubà (Menorca), forma muy similar a la única otra conocida del género (B. Muletensis, de Mallorca). Los húmeros de B. Talaioticus son algo más cortos y robustos que los de
B. Muletensis, representando esta incipiente adaptaciĂłn cavadora bien un paralelismo con respecto a la tendencia de Alytes, o bien una reversiĂłn evolutiva de Baleaphryne hacia morfologias menos especializadas. Se atribuyen restos menorquines del siglo II aC a B. Talaioticus, lo que sugiere que esta especie pueda no haberse extinguido
Do graphic and textual interactive content organizers have the same impact on hypertext processing and learning outcome?
International audienc
- …