Gravitational shocks as a key ingredient of Gamma-Ray Bursts

We identify a novel physical mechanism that may be responsible for energy release in $\gamma$-ray bursts. Radial perturbations in the neutron core, induced by its collision with collapsing outer layers during the early stages of supernova explosions, can trigger a gravitational shock, which can readily eject a small but significant fraction of the collapsing material at ultra-relativistic speeds. The development of such shocks is a strong-field effect arising in near-critical collapse in General Relativity and has been observed in numerical simulations in various contexts, including in particular radially perturbed neutron star collapse, albeit for a tiny range of initial conditions. Therefore, this effect can be easily missed in numerical simulations if the relevant parameter space is not exhaustively investigated. In the proposed picture, the observed rarity of $\gamma$-ray bursts would be explained if the relevant conditions for this mechanism appear in only about one in every $10^4-10^5$ core collapse supernovae. We also mention the possibility that near-critical collapse could play a role in powering the central engines of Active Galactic Nuclei.Comment: 9 pages, 3 figure

Endoscopic diagnosis of gastric peptic ulcer penetrating into the liver

A 61-year-old man was admitted with upper gastrointestinal bleeding. Endoscopy showed a large gastric peptic ulcer with a pseudotumoral mass protruding from the ulcer bed. Histological examination of biopsies taken from the mass revealed distorted hepatic tissue and inflammatory changes. Hepatic penetration was diagnosed as the cause of bleeding. Surgery findings confirmed the endoscopic diagnosis

Cost-effectiveness analysis of tropisetron vs. chlorpromazine-dexamethasone in the control of acute emesis induced by highly emetogenic chemotherapy in children

To perform a cost-effectiveness analysis (CEA) between a standard antiemetic regimen-chlorpromazine + dexamethasone (CPM-DEX)- and a 5-HT3 receptor antagonist-tropisetron (TROP)--in the control of acute emesis induced by highly emetogenic chemotherapy in children, considering two analytic perspectives: hospital and patients. METHODS: The CEA was performed by constructing a decision tree, for both analytic perspectives, of the possible outcomes of treatment with TROP (single 0.2 mg/kg i.v.) or CPM (5-15 mg i.v. infusion for 3 doses) plus DEX (2 mg/m2 i.v. bolus i.v. x2). The patients were stratified by age in two groups (2-12 and 13-17). To estimate the probability of each endpoint at the decision tree we have taken as a base a trial developed in the Department of Pediatrics. Direct medical cost of primary therapy, failure, complications and side effects were included in the cost calculations. RESULTS: From patients' analytic perspective, TROP was more cost-effective than CPM-DEX for both groups of patients. Discrepancy between both analytic perspectives in 13-17 year-old patient's group was resolved in favour of the option chosen from the patients' analytic perspective (TROP). Sensitivity analysis showed the reliability of the results. CONCLUSIONS: 1. TROP was more cost-effective than CPM-DEX. 2. Taking into account the patients' analytic perspective is essential when we compare antiemetics pharmacoeconomically. 3. It seems necessary to increase the effectiveness of TROP in pediatric patients receiving highly emetogenic chemotherapy with strategies such as the addition of a steroid

Recombinant Human Erythropoietin for the Treatment of Anemia in Children With Solid Malignant Tumors

Cancer is often associated with chronic anemia which frequently requires blood transfusions. This study was performed to assess the efficacy and safety of r-HuEPO therapy in children with cancer. PATIENTS AND METHODS: Twenty-five patients under 18 years of age with solid malignant tumors were treated with 150 U/kg/day of r-HuEPO 5 times weekly for 12 weeks. Response was defined as an increase of the baseline hemoglobin level by at least 2 g/dl. r-HuEPO patients were compared to 25 matched historical controls. RESULTS: Response was achieved in 72% of r-HuEPO patients. Hemoglobin level increased from 9.8 +/- 0.6 g/dl at baseline to 12.4 +/- 1.7 g/dl at the end of treatment in the r-HuEPO group and increased from 9.5 +/- 0.7 g/dl to 9.6 +/- 1.4 g/dl in the control group (P < .001, Student's t-test). Only 16% of patients receiving r-HuEPO required blood transfusions vs 96% of control patients (P < .001, Student's t-test), with mean units of blood transfused per patient being 0.35 in the r-HuEPO group and 3.56 in controls (P < .001, Student's t-test). There was a statistically significance improvement in Karnofsky's index in r-HuEPO patients. No adverse reaction related to r-HuEPO therapy was observed. CONCLUSIONS: r-HuEPO is a safe and effective means of increasing hemoglobin level and reducing blood requirements in children with solid malignant tumors receiving chemotherapy

Microorganisms present in artisanal fermented food from South America

Artisanal fermented products (foods and beverages) are produced in an artisanal way in many countries around the world. The main purpose of fermentation is to preserve the food, improve its safety, increase the nutritional and health-promoting value and add specific flavours. In South America, there is a great variety of fermented food produced in an artisanal way. Different raw materials are used such as potatoes, sweet potato, cassava, maize, rice, milk (cow, ewe, goat) and meat (beef, goat, lamb, llama and guanaco). Some of these fermented foods are typical of the region and are part of the culture of native communities, e.g. tocosh, masa agria, puba flour, charqui, chicha, champu and cauim among others (indigenous foods). However, other fermented foods produced in South America introduced by mainly European immigration, such as cheeses and dry sausages, and they are also produced in many different parts of the world. In this work, the microbial composition of the different artisanal fermented products produced in South America is reviewed, taking into consideration the associated raw materials, fermentation conditions and methodologies used for their production.Fil: Jimenez, María Eugenia. Teagasc - Irish Agriculture And Food Development Authority; Irlanda. Apc Microbiome Ireland; Irlanda. Universidad Nacional de Jujuy. Centro Interdisciplinario de Investigaciones en Tecnologías y Desarrollo Social para el Noa. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Salta-Jujuy. Centro Interdisciplinario de Investigaciones en Tecnologías y Desarrollo Social para el Noa; ArgentinaFil: O'Donovan, Ciara M.. Apc Microbiome Ireland; Irlanda. Teagasc - Irish Agriculture And Food Development Authority; IrlandaFil: Fernandez de Ullivarri, Miguel. Apc Microbiome Ireland; IrlandaFil: Cotter, Paul D.. Apc Microbiome Ireland; Irlanda. Teagasc - Irish Agriculture And Food Development Authority; Irland

Photoluminescent properties of electrochemically synthetized ZnO nanotubes

ZnO nanotubes were prepared by a sequential combination of electrochemical deposition, chemical attack and regeneration. ZnO nanocolumns were initially electrodeposited on conductive substrates and then converted into nanotubes by a process involving chemical etching and subsequent regrowth. The morphology of these ZnO nanocolumns and derived nanotubes was monitored by Scanning Electron Microscopy and their optical properties was studied by photoluminescence spectroscopy. Photoluminescence were measured as a function of temperature, from 6 to 300 K, for both nanocolumns and nanotubes. In order to study the behaviour of induced intrinsic defect all ZnO films were annealed in air at 400 °C and their photoluminescent properties were also registered before and after annealing. The behaviour of photoluminescence is explained taking into account the contribution of different point defects. A band energy diagram related to intrinsic defects was proposed to describe the behaviour of photoluminescence spectraThis work was supported by Ministerio de Economia y Competitividad (ENE2013-46624-C4-4-R) and Generalitat Valenciana (Prometeus 2014/044).Gracia Jimenez, JM.; Cembrero Cil, J.; Mollar García, MA.; Marí Soucase, B. (2016). Photoluminescent properties of electrochemically synthetized ZnO nanotubes. Materials Characterization. 119:152-158. https://doi.org/10.1016/j.matchar.2016.07.022S15215811

Sensitivity of polyamine metabolism to glucose deprivation is increased in neuroblastoma cells with N-myc amplification

Ornithine-derived polyamines are essential for cell proliferation, and their levels are elevated in many human tumors. Neuroblastoma, the most frequent extra-cranial solid tumor in children, harbors amplification of n-myc oncogene (which enhances polyamine metabolism) in 25% of the cases. In the present communication, the relevance of n-myc amplification in several metabolic features of human neuroblastoma cell lines is studied. A previously unknown linkage between glycolysis impairment and polyamine reduction, related to n-myc amplification, is unveiled. Results show that glycolysis inhibition is able to trigger signaling events leading to the reduction of N-Myc protein levels and subsequent decrease of both ornithine decarboxylase expression and polyamine levels, accompanied by cell cycle blockade preceding cell death. Metabolism-targeted therapies are emerging as new approaches for cancer treatment. New anti-tumor strategies could take advantage of the direct relationship between glucose deprivation and PA metabolism impairment leading to cell death described in the present work, and its apparent dependence on n-myc amplification in the case of neuroblastoma. Combined therapies targeting glucose metabolism and polyamine synthesis could be effective in the treatment of n-myc amplified tumors.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech. This work has been funded by Grants SAF2011-26518 (Ministerio de Economía y Competitividad, Spain), Excellence Projects CTS-1507 and CVI-06585 (Junta de Andalucía, Spain) and BIO-267 (fondos PAIDI, Junta de Andalucía, Spain). MVRP was the recipient of a FPU long-term fellowship (Ministerio de Educación, Cultura y Deporte, Spain) and a “III Plan Propio de Investigación” short-term fellowship (University of Málaga). CIBERER is an initiative of Instituto de Salud Carlos III. This communication has the support of a travel grant "Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech"

Silver-enriched ZnO:Ag thin films deposited by magnetron co-sputtering: Post annealing effects on structural and physical properties

The ZnO semiconductor is probably among the most mentioned compounds in the scientific literature during the last decade, which is mainly due to its wide spectrum of applications. Compounds based on ZnO (in doped or composite form) are of great relevance for the development of high-tech devices. In this work, we present the growth and characterization of samples deposited by DC Magnetron co-sputtering from two pure Zn and Ag targets in an O2 / Ar atmosphere. The samples were characterized as deposited and after an annealing treatment in a reducing atmosphere. We have used XRD, RBS, ellipsometry, UV visible photoluminescence, and electrical measurements for sample characterization. The results revealed the amorphization of ZnO when the Ag content increases and, after annealing, a mixture of crystalline phases was detected for the samples with higher Ag content. It is also demonstrated the strong effect of the presence of Ag atoms in the stimulated optical and electrical responses from ZnO:Ag compounds obtained in this wor

Crowdsourcing the corpasome

The suffix -ome conveys “comprehensiveness” in some way. The idea of the Corpasome started half-jokingly, acknowledging the efforts to sequence five members of my family. After the unexpected response from many scientists from around the world, it has become clear how useful this approach could be for understanding the genomic information contained in our personal genomics tests