1,944 research outputs found

    El hombre y el derecho viven en la tradición.

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    Negative pressures in CaWO4 nanocrystals

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    Tetragonal scheelite-type CaWO4 nanocrystals recently prepared by a hydrothermal method show an enhancement of its structural symmetry with the decrease in nanocrystal size. The analysis of the volume dependence of the structural parameters in CaWO4 nanocrystals with the help of ab initio total-energy calculations shows that the enhancement of the symmetry in the scheelite-type nanocrystals is a consequence of the negative pressure exerted on the nanocrystals; i.e., the nanocrystals are under tension. Besides, the behavior of the structural parameters in CaWO4 nanocrystals for sizes below 10 nm suggests an onset of a scheelite-to-zircon phase transformation in good agreement with the predictions from our ab initio calculations. CaWO4 nanocrystals exhibit a reconstructive-type mechanism for the scheelite-to-zircon phase transition that seems to follow the tetragonal path that links both structures. This result is in contrast with the mechanism recently proposed for this transition in bulk ZrSiO4 where the transition goes through an intermediate monoclinic [email protected]

    A theropod trackway providing evidence of a pathological foot from the exceptional locality of Las Hoyas (upper Barremian, Serranía de Cuenca, Spain)

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    We describe a trackway (LH-Mg-10-16) occurring in laminated carbonated limestones of the Las Hoyas locality, Serranía de Cuenca, Spain. It is unmistakably a large theropod dinosaur trackway encompassing two unusual aspects, namely, wide-steps, and a set of equally deformed left footprints (with a dislocated digit). The layer also preserves other vertebrate trails (fish Undichna) and different impressions in the sediment. To address these complex settings, we devised a multidisciplinary approach, including the ichnological and taphonomical descriptions, characterisation of the rock lithofacies using thin-sections, 3D structured-light digitalisation with a high precision of 200-400 μm, and a geometric morphometric comparison with a large sample of bipedal dinosaur trackways. Sedimentary analyses showed that the trackway was produced in a humid, benthonic microbial mat, the consistency and plasticity of which enabled the preservation of the details of the movement of the animal. The results of the geometric analysis indicate that the 'wide-steps' of the trackway is not unusual compared to other trackways, providing evidence that it was made by a single individual with an estimated hip height approximately 2 m. Analogous pathologies in extant archosaurs that yield the combination of wide steps and deformed digits in the same trackway were considered. All results mutually support the hypothesis that a large theropod dinosaur, with a pathological foot, generated the trackway as it crossed an area of shallow water while slowly walking towards the main water source, thus stepping steadily over the benthonic mat over which multiple fish were swimming

    Accelerating to Zero: Strategies to Eliminate Malaria in the Peruvian Amazon.

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    AbstractIn February 2014, the Malaria Elimination Working Group, in partnership with the Peruvian Ministry of Health (MoH), hosted its first international conference on malaria elimination in Iquitos, Peru. The 2-day meeting gathered 85 malaria experts, including 18 international panelists, 23 stakeholders from different malaria-endemic regions of Peru, and 11 MoH authorities. The main outcome was consensus that implementing a malaria elimination project in the Amazon region is achievable, but would require: 1) a comprehensive strategic plan, 2) the altering of current programmatic guidelines from control toward elimination by including symptomatic as well as asymptomatic individuals for antimalarial therapy and transmission-blocking interventions, and 3) the prioritization of community-based active case detection with proper rapid diagnostic tests to interrupt transmission. Elimination efforts must involve key stakeholders and experts at every level of government and include integrated research activities to evaluate, implement, and tailor sustainable interventions appropriate to the region

    Sternal plate fixation for sternal wound reconstruction: initial experience (Retrospective study)

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    <p>Abstract</p> <p>Background</p> <p>Median sternotomy infection and bony nonunion are two commonly described complications which occur in 0.4 - 5.1% of cardiac procedures. Although relatively infrequent, these complications can lead to significant morbidity and mortality. The aim of this retrospective study is to evaluate the initial experience of a transverse plate fixation system following wound complications associated with sternal dehiscence with or without infection following cardiac surgery.</p> <p>Methods</p> <p>A retrospective chart review of 40 consecutive patients who required sternal wound reconstruction post sternotomy was performed. Soft tissue debridement with removal of all compromised tissue was performed. Sternal debridement was carried using ronguers to healthy bleeding bone. All patients underwent sternal fixation using three rib plates combined with a single manubrial plate (Titanium Sternal Fixation System<sup>®</sup>, Synthes). Incisions were closed in a layered fashion with the pectoral muscles being advanced to the midline. Data were expressed as mean ± SD, Median (range) or number (%). Statistical analyses were made by using Excel 2003 for Windows (Microsoft, Redmond, WA, USA).</p> <p>Results</p> <p>There were 40 consecutive patients, 31 males and 9 females. Twenty two patients (55%) were diagnosed with sternal dehiscence alone and 18 patients (45%) with associated wound discharge. Thirty eight patients went on to heal their wounds. Two patients developed recurrent wound infection and required VAC therapy. Both were immunocompromised. Median post-op ICU stay was one day with the median hospital stay of 18 days after plating.</p> <p>Conclusion</p> <p>Sternal plating appears to be an effective option for the treatment of sternal wound dehiscence associated with sternal instability. Long-term follow-up and further larger studies are needed to address the indications, benefits and complications of sternal plating.</p

    A framework to assess the resilience of farming systems

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    Agricultural systems in Europe face accumulating economic, ecological and societal challenges, raising concerns about their resilience to shocks and stresses. These resilience issues need to be addressed with a focus on the regional context in which farming systems operate because farms, farmers’ organizations, service suppliers and supply chain actors are embedded in local environments and functions of agriculture. We define resilience of a farming system as its ability to ensure the provision of the system functions in the face of increasingly complex and accumulating economic, social, environmental and institutional shocks and stresses, through capacities of robustness, adaptability and transformability. We (i) develop a framework to assess the resilience of farming systems, and (ii) present a methodology to operationalize the framework with a view to Europe’s diverse farming systems. The framework is designed to assess resilience to specific challenges (specified resilience) as well as a farming system’s capacity to deal with the unknown, uncertainty and surprise (general resilience). The framework provides a heuristic to analyze system properties, challenges (shocks, long-term stresses), indicators to measure the performance of system functions, resilience capacities and resilience-enhancing attributes. Capacities and attributes refer to adaptive cycle processes of agricultural practices, farm demographics, governance and risk management. The novelty of the framework pertains to the focal scale of analysis, i.e. the farming system level, the consideration of accumulating challenges and various agricultural processes, and the consideration that farming systems provide multiple functions that can change over time. Furthermore, the distinction between three resilience capacities (robustness, adaptability, transformability) ensures that the framework goes beyond narrow definitions that limit resilience to robustness. The methodology deploys a mixed-methods approach: quantitative methods, such as statistics, econometrics and modelling, are used to identify underlying patterns, causal explanations and likely contributing factors; while qualitative methods, such as interviews, participatory approaches and stakeholder workshops, access experiential and contextual knowledge and provide more nuanced insights. More specifically, analysis along the framework explores multiple nested levels of farming systems (e.g. farm, farm household, supply chain, farming system) over a time horizon of 1-2 generations, thereby enabling reflection on potential temporal and scalar trade-offs across resilience attributes. The richness of the framework is illustrated for the arable farming system in Veenkoloniën, the Netherlands. The analysis reveals a relatively low capacity of this farming system to transform and farmers feeling distressed about transformation, while other members of their households have experienced many examples of transformation

    Statins but Not Aspirin Reduce Thrombotic Risk Assessed by Thrombin Generation in Diabetic Patients without Cardiovascular Events: The RATIONAL Trial

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    The systematic use of aspirin and statins in patients with diabetes and no previous cardiovascular events is controversial. We sought to assess the effects of aspirin and statins on the thrombotic risk assessed by thrombin generation (TG) among patients with type II diabetes mellitus and no previous cardiovascular events.Prospective, randomized, open, blinded to events evaluation, controlled, 2×2 factorial clinical trial including 30 patients randomly allocated to aspirin 100 mg/d, atorvastatin 40 mg/d, both or none. Outcome measurements included changes in TG levels after treatment (8 to 10 weeks), assessed by a calibrated automated thrombogram. At baseline all groups had similar clinical and biochemical profiles, including TG levels. There was no interaction between aspirin and atorvastatin. Atorvastatin significantly reduced TG measured as peak TG with saline (85.09±55.34 nmol vs 153.26±75.55 nmol for atorvastatin and control groups, respectively; p = 0.018). On the other hand, aspirin had no effect on TG (121.51±81.83 nmol vs 116.85±67.66 nmol, for aspirin and control groups, respectively; p = 0.716). The effects of treatments on measurements of TG using other agonists were consistent.While waiting for data from ongoing large clinical randomized trials to definitively outline the role of aspirin in primary prevention, our study shows that among diabetic patients without previous vascular events, statins but not aspirin reduce thrombotic risk assessed by TG.ClinicalTrials.gov NCT00793754

    Electrochemical study of gold recovery from ammoniacal thiosulfate, simulating the PCBs leaching of mobile phones

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    [EN] The high volume of sales and the high degree of obsolescence of mobile phones, together with the reduction of the natural reserves of the metals used in the composition of their printed circuit boards (PCBs), makes the recycling of these devices economically and environmentally attractive. Moreover, the search for the reduction of toxicity levels inherent to the gold leaching processes with alternatives to cyanide, such as thiosulfate is a priority. Thus, it is necessary to search for efficient alternatives for the recovery of gold from solutions containing thiosulfate, in the presence of copper, used in the leaching of PCBs of mobile phones. One of these alternatives could be the electrochemical recovery of the metals present in solution. Thus, this study aimed to verify some variables involved in the process of recovery of gold and copper and to determine the electrochemical yield obtained for these solutions. Initially, cyclic scanning voltammetry with a rotating disk electrode (RDE) was performed to verify the electrochemical behavior of gold and copper in solution. Then, electrowinning tests were used to determine the recovery rates of these metals and to calculate the yield obtained in the process. The results showed that this electrochemical reaction is mass transport controlled, which allowed the calculation of the diffusion coefficients of the metal in solution. In real solutions, the gold fraction recovered reached a 94%, and the copper fraction recovered was 95%, applying electrode potential values of -500 mV(Ag/AgCl) and -700 mV(Ag/AgCl), respectively. The current efficiency for the gold electrowinning achieved in the experiments was lower than 3%. (c) 2017 Elsevier Ltd. All rights reserved.The authors would like to thank the Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES) and Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq) from Brazil for financial support.Kasper, AC.; Veit, HM.; García Gabaldón, M.; Pérez-Herranz, V. (2018). Electrochemical study of gold recovery from ammoniacal thiosulfate, simulating the PCBs leaching of mobile phones. Electrochimica Acta. 259:500-509. https://doi.org/10.1016/j.electacta.2017.10.161S50050925

    Safety and preliminary efficacy data of a novel Casein Kinase 2 (CK2) peptide inhibitor administered intralesionally at four dose levels in patients with cervical malignancies

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    <p>Abstract</p> <p>Background</p> <p>Cervical cancer is now considered the second leading cause of death among women worldwide, and its incidence has reached alarming levels, especially in developing countries. Similarly, high grade squamous intraepithelial lesion (HSIL), the precursor stage for cervical cancer, represents a growing health problem among younger women as the HSIL management regimes that have been developed are not fully effective. From the etiological point of view, the presence of Human Papillomavirus (HPV) has been demonstrated to play a crucial role for developing cervical malignancies, and viral DNA has been detected in 99.7% of cervical tumors at the later stages. CIGB-300 is a novel cyclic synthetic peptide that induces apoptosis in malignant cells and elicits antitumor activity in cancer animal models. CIGB-300 impairs the Casein Kinase (CK2) phosphorylation, by targeting the substrate's phosphoaceptor domain. Based on the perspectives of CIGB-300 to treat cancer, this "first-in-human" study investigated its safety and tolerability in patients with cervical malignancies.</p> <p>Methods</p> <p>Thirty-one women with colposcopically and histologically diagnosed microinvasive or pre-invasive cervical cancer were enrolled in a dose escalating study. CIGB-300 was administered sequentially at 14, 70, 245 and 490 mg by intralesional injections during 5 consecutive days to groups of 7 – 10 patients. Toxicity was monitored daily until fifteen days after the end of treatment, when patients underwent conization. Digital colposcopy, histology, and HPV status were also evaluated.</p> <p>Results</p> <p>No maximum-tolerated dose or dose-limiting toxicity was achieved. The most frequent local events were pain, bleeding, hematoma and erythema at the injection site. The systemic adverse events were rash, facial edema, itching, hot flashes, and localized cramps. 75% of the patients experienced a significant lesion reduction at colposcopy and 19% exhibited full histological regression. HPV DNA was negative in 48% of the previously positive patients. Long term follow-up did not reveal recurrences or adverse events.</p> <p>Conclusion</p> <p>CIGB 300 was safe and well tolerated. This is the first clinical trial where a drug has been used to target the CK2 phosphoaceptor domain providing an early proof-of-principle of a possible clinical benefit.</p

    CIGB-300, a synthetic peptide-based drug that targets the CK2 phosphoaceptor domain. Translational and clinical research

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    CK2 represents an oncology target scientifically validated. However, clinical research with inhibitors of the CK2-mediated phosphorylation event is still insufficient to recognize it as a clinically validated target. CIGB-300, an investigational peptide-based drug that targets the phosphoaceptor site, binds to a CK2 substrate array in vitro but mainly to B23/nucleophosmin in vivo. The CIGB-300 proapoptotic effect is preceded by its nucleolar localization, inhibition of the CK2-mediated phosphorylation on B23/nucleophosmin and nucleolar disassembly. Importantly, CIGB-300 shifted a protein array linked to apoptosis, ribosome biogenesis, cell proliferation, glycolisis, and cell motility in proteomic studies which helped to understand its mechanism of action. In the clinical ground, CIGB-300 has proved to be safe and well tolerated in a First-in-Human trial in women with cervical malignancies who also experienced signs of clinical benefit. In a second Phase 1 clinical trial in women with cervical cancer stage IB2/II, the MTD and DLT have been also identified in the clinical setting. Interestingly, in cervical tumors the B23/nucleophosmin protein levels were significantly reduced after CIGB-300 treatment at the nucleus compartment. In addition, expanded use of CIGB-300 in case studies has evidenced antitumor activity when administered as compassional option. Collectively, our data outline important clues on translational and clinical research from this novel peptide-based drug reinforcing its perspectives to treat cancer and paving the way to validate CK2 as a promising target in oncology.Fil: Perea, Silvio E.. Center for Genetic Engineering and Biotechnology; CubaFil: Baladron, Idania. Center for Genetic Engineering and Biotechnology; CubaFil: Garcia, Yanelda. Center for Genetic Engineering and Biotechnology; CubaFil: Perera, Yasser. Center for Genetic Engineering and Biotechnology; CubaFil: Lopez, Adlin. Center for Genetic Engineering and Biotechnology; CubaFil: Soriano, Jorge L.. Center for Genetic Engineering and Biotechnology; Cuba. General Hospital ‘‘Hermanos Ameijeiras’; CubaFil: Batista, Noyde. Center for Genetic Engineering and Biotechnology; Cuba. General Hospital ‘‘Hermanos Ameijeiras’; CubaFil: Palau, Aley. Center for Genetic Engineering and Biotechnology; Cuba. General Hospital ‘‘Hermanos Ameijeiras’; CubaFil: Hernández, Ignacio. Center for Genetic Engineering and Biotechnology; CubaFil: Farina, Hernán Gabriel. Universidad Nacional de Quilmes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Garcia, Idrian. Center for Genetic Engineering and Biotechnology; CubaFil: Gonzalez, Lidia. Center for Genetic Engineering and Biotechnology; CubaFil: Gil, Jeovanis. Center for Genetic Engineering and Biotechnology; CubaFil: Rodriguez, Arielis. Center for Genetic Engineering and Biotechnology; CubaFil: Solares, Margarita. Center for Genetic Engineering and Biotechnology; CubaFil: Santana, Agueda. Center for Genetic Engineering and Biotechnology; CubaFil: Cruz, Marisol. Center for Genetic Engineering and Biotechnology; CubaFil: Lopez, Matilde. Center for Genetic Engineering and Biotechnology; CubaFil: Valenzuela, Carmen. Center for Genetic Engineering and Biotechnology; CubaFil: Reyes, Osvaldo. Center for Genetic Engineering and Biotechnology; CubaFil: López Saura, Pedro A.. Center for Genetic Engineering and Biotechnology; CubaFil: González, Carlos A.. Center for Genetic Engineering and Biotechnology; CubaFil: Diaz, Alina. Center for Genetic Engineering and Biotechnology; CubaFil: Castellanos, Lila. Center for Genetic Engineering and Biotechnology; CubaFil: Sanchez, Aniel. Center for Genetic Engineering and Biotechnology; CubaFil: Betancourt, Lazaro. Center for Genetic Engineering and Biotechnology; CubaFil: Besada, Vladimir. Center for Genetic Engineering and Biotechnology; CubaFil: González, Luis J.. Center for Genetic Engineering and Biotechnology; CubaFil: Garay, Hilda. Center for Genetic Engineering and Biotechnology; CubaFil: Gómez, Roberto. Center for Genetic Engineering and Biotechnology; CubaFil: Gomez, Daniel Eduardo. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Nacional de Quilmes; ArgentinaFil: Alonso, Daniel Fernando. Universidad Nacional de Quilmes; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas; ArgentinaFil: Perrin, Phillipe. No especifíca;Fil: Renualt, Jean Yves. No especifíca;Fil: Sigman, Hugo. No especifíca;Fil: Herrera, Luis. Center for Genetic Engineering and Biotechnology; CubaFil: Acevedo, Boris. Center for Genetic Engineering and Biotechnology; Cub
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