Evidence for a Bis(Elongated s)-Dihydrideborate Coordinated to Osmium

The formation and Atoms in Molecules (AIM) analysis of osmium(IV) and osmium(II) complexes containing dihydrideborate groups and primary aminoborane ligands are reported. Complex OsH6(PiPr3)2 (1) loses a hydrogen molecule and the resulting unsaturated OsH4(PiPr3)2 species coordinates 9-borabicycle[3.3.1]nonane (HBbn) and pinacolborane (HBpin) to give the dihydrideborate derivatives OsH3{¿2-H, H-(H2BR2)}(PiPr3)2 (BR2 = Bbn (2), Bpin (3)). The bonding situation in these compounds and in the related osmium(II) derivative Os(Bcat){¿2-H, H-(H2Bcat)}(CO)(PiPr3)2 (4) (HBcat = catecholborane) has been analyzed by the AIM method. The Laplacian distributions in the Os-H-B plane exhibit a four-membered cyclic topology possessing two Os-H and two B-H bond critical points associated with one OsHHB ring critical point, which resembles that found for B2H6. The tetrahydride OsH4(PiPr3)2 also coordinates catecholborane, which initially affords OsH3{¿2-H, H-(H2Bcat)}(PiPr3)2 (5). In contrast to 2 and 3, complex 5 reacts with a second molecule of HBcat to give the elongated s-borane-{bis(elongated s)-dihydrideborate}-osmium(II) derivative OsH(¿3-H2Bcat)(¿2-HBcat)(PiPr3)2 (6). Complexes 5 and 6 have been also analyzed via the AIM method. Complex 5 displays the same topology as complexes 2-4. However, the OsH2B unit of 6 shows, besides the Os-H and B-H bond critical points, an additional Os-B bond critical point, which is associated with a bond path running between these atoms. This double triangular topology is completed with the respective ring critical points. Reactions of 1 with dimethylamine-borane (H3B·NHMe2) and tert-butylamine-borane (H3B·NH2 tBu) give OsH2(¿2:¿2-H2BNR2)(PiPr3)2 (NR2 = NMe2 (7), NHtBu (8)). The AIM analyses of 7 and 8 also reveal the occurrence of an Os-B bond critical point associated with a bond path running between those atoms. However, neither Os-H bond critical points nor bond paths are observed in the latter species

El fracaso de Copenhague desde la teoría de juegos

Los acuerdos medioambientales de carácter supranacional parecen “condenados” a no funcionar debido, fundamentalmente, a la característica del propio medio ambiente como bien público global. Si uno de los agentes implicados toma la iniciativa con movimientos hacia un cambio tecnológico, más respetuoso en términos medioambientales y más eficiente en términos energéticos, podría cambiar los resultados y lograr la buscada reducción en los niveles de contaminación. La UE ha adoptado esa posición pero la cumbre de Copenhague, lejos de corroborar que el resto de países seguirán la estrategia iniciada por la UE, ha sido un fracaso en términos de mayor compromiso por parte de países que, de momento, siguen fuera del protocolo, básicamente EEUU. El objetivo de este trabajo es analizar qué circunstancias han podido propiciar (intencionadamente o no) el fracaso en la búsqueda de apoyos en la cumbre de Copenhague

The Regulatory Effect of National Allocation Plans on CO2 Emissions

En los últimos años la literatura económica ha prestado especial atención a la relación entre emisiones contaminantes y actividad económica. El análisis de esta relación tiene en cuenta tres efectos básicos: escala, estructura y técnico. El interés de este trabajo se centra en un nuevo efecto, el efecto regulador que considera la relación entre determinadas medidas de política económica ambiental y las emisiones de CO2. En concreto, se estudia si los Planes Nacionales de Asignación (PNA) han logrado ser efectivos a la hora de reducir las citadas emisiones. Para ello, se realizan diferentes estimaciones econométricas con datos de seis países de la Unión Europea (UE) y considerando los PNA como variables cualitativas

The regulation factor as a determinant of energy consumption and CO2 emissions

En los últimos a˜nos la literatura económica ha prestado especial atención a la relación entre emisiones contaminantes, consumo de energía y actividad económica. Este trabajo pretende profundizar en dicha relación, prestando especial atención al posible efecto que la aplicación de los planes nacionales de asignación ha tenido sobre el comportamiento emisor y energético de los países analizados. En concreto, se estudia si han logrado ser efectivos a la hora de reducir 2 variables clave como son las emisiones de CO2 y el consumo de energía, incluso cuando se han producido caídas en la actividad económica debido a la crisis de los últimos a˜nos. Los países que se han tenido en cuenta para este trabajo son: Espa˜na, Francia, Alemania, Italia, Portugal y Reino Unido. El periodo considerado es 2000-2010, y se utilizan datos publicados por la Unión Europea relativos a emisiones, asignaciones de derechos, consumo de energía y nivel de producción de los países analizados

Antiangiogenic Therapy in Epithelial Ovarian Cancer

Approximately 75% of women with ovarian cancer are diagnosed at advanced stages (FIGO stage III/IV), with 15-23 months median global survival and 20% 5-year survival. Angiogenesis plays an important role in tumour development and proliferation. Increased angiogenesis is associated with worse clinical outcome in ovarian cancer. Here we review the play of bevacizumab in the treatment of ovarian cancer and also other antiangiogenic drugs. In total, to date there are no promising results for most of the reviewed antiangiogenic agents, except those already known for bevacizumab, trebananib, pazopanib, cediranib and nintedanib. Ongoing research will shed more light on this fascinating tumour process and its control

The antitumor drug vinblastine induces the phosphorylation of annexin A2

Comunicaciones a congreso

Use of metalloproteomics to access environmental stress in the free-living mice mus spretus

Comunicaciones a congreso

Effect of sperm concentration and storage temperature on goat spermatozoa during liquid storage

The use of cooled semen is relatively common in goats. There are a number of advantages of cooled semen doses, including easier handling of artificial insemination (AI) doses, transport, more AI doses per ejaculate, and higher fertility rates in comparison with frozen AI doses. However, cooled semen has a short shelf life. The objective of this study was to examine the effect of temperature and sperm concentration on the in vitro sperm quality during liquid storage for 48 h, including sperm motility and kinetics, response to oxidation, mitochondrial membrane potential (MMP) and DNA fragmentation in goats. Three experiments were performed. In the first, the effects of liquid preservation of semen at different temperatures (5 °C or 17 °C), durations (0, 24 and 48 h) and sperm concentrations (250 × 106 sperm/mL (1:2 dilution rate), 166.7 × 106 sperm/mL (1:3 dilution rate) or 50 × 106 sperm/mL (1:10 dilution rate)) on sperm motility and kinetics were studied. In the second experiment, the effect of temperature, sperm washing and concentration on sperm motility and DNA fragmentation was studied. Finally, the effect of sperm concentration and duration of storage at 5 °C on sperm motility, response to oxidative stress and MMP was examined. We found that refrigerated liquid storage of goat sperm impaired sperm quality, such as motility, MMP and response to oxidation, as storage time increased; however, sperm DNA fragmentation index was not significantly affected. Liquid storage at 5 °C preserved higher total motility than at 17 °C. Moreover, we observed that the reduction of sperm concentration below 500 × 106 sperm/mL did not seem to improve the quality of spermatozoa conserved in milk-based extender in the conditions teste

Utilización inadecuada de un servicio de urgencias hospitalario. Una evaluación con criterios explícitos

ResumenFundamentoExiste un crecimiento del número de visitas en los servicios de urgencias hospitalarios (SUH) con una elevada proporción de utilización inapropiada. Los métodos empleados para identificar el uso inadecuado basados en criterios implícitos limitan las comparaciones entre hospitales. El objetivo de este estudio es conocer la proporción de visitas inadecuadas en un SUH y sus factores asociados, utilizando un método objetivo.Material y métodoSe utilizó un instrumento basado en criterios explícitos e independientes del diagnóstico para identificar las visitas inapropiadas en una muestra aleatoria de 1.845 pacientes mayores de 14 años que acudieron a los servicios médicos de un SUH, y se analizaron los factores asociados a la demanda inadecuada.ResultadosLa proporción de urgencias inadecuadas fue del 26,8% (495/1.845). En el análisis bivariante la menor edad, la ausencia de patología asociada, las visitas espontáneas y determinados grupos diagnósticos (enfermedades de la piel, músculo-esqueléticas, mentales y sintamos mal definidos) se asociaron a una mayor proporción de uso inadecuado del SUH. Al ajustar las variables mediante regresión logística, la edad, la patología asociada, las consultas espontáneas y los grupos diagnósticos, mantuvieron la asociación con el uso inadecuado, pero otras variables como el ser mujer y la llegada al SUH fuera del turno de noche también se asociaron a una mayor utilización inadecuada.ConclusionesAl menos la cuarta parte de las visitas realizadas en los servicios médicos de los SUH no requieren atención urgente. La inadecuación de las visitas se asocia a características del paciente y el proceso asistido.SummaryBackgroundSeveral studies have shown a growth in the number of visits to accident and emergency (A&E) hospital departments with a high proportion of inappropriate utilization. Methods to identify improper use based on implicit criteria limit the comparisons between hospitals. The aim of this study is to know the proportion of inappropriate attendance's in an A&E department and their associated factors, using a method with objective criteria.MethodsAn instrument based on diagnosis-independent explicit criteria was used to identify inappropriate visits in a random sample of 1845 14-year-old greater patients attended to A&E medical services, and the factors associated with improper demand were analysed.ResultsThe proportion of inappropriate attendance's was of the 26,8% (495/1.845). The unadjusted analysis show that the smaller age, absence of comorbidity, spontaneous visit and some diagnostic groups (diseases of the skin, muscle-skeletal, mental, and bad defined symptoms) were associated to a greater proportion of improper use. Upon adjusting the variables through logistics regression, the age, associated pathology, the spontaneous attendance's and diagnostic groups, maintained the association with improper use, but other variables as woman gender, and night hours were also associated to inappropriate utilization.ConclusionsAt least the fourth part of the attendance's in the A&E medical services do not require urgent attention. Inappropriate utilization is associated to characteristic of the patient and the attended process

Electrodes based on nafion and epoxy-graphene composites for improving the performance and durability of open cathode fuel cells, prepared by electrospray deposition

Fabrication of electrodes for polymer electrolyte fuel cells is a intriguing process in which a balance between gas transport, electrical conductivity, proton transport and water managing must be optimized. In this work four different electrodes prepared by electrospray deposition have been studied using different catalytic inks, in which Nafion and epoxy doped with Graphene-Nanoplatelets were used as binders. After studying the behavior of those electrodes in a single open cathode fuel cell proton electrolyte membrane, it is clear that the addition of epoxy as binder doped with graphene, improves the performance of the fuel cell and increase the mechanical stability of the electrode avoiding the loose of catalyst during the electrode manipulation in the fuel cell assembly process and the durability of the fuel cell. To explain this behavior, an ex-situ study was carried out, in which properties such as its surface morphology, hydrophobicity and electrical and thermal conductivity of those electrodes were studied. From the results of this study, such improvement in the performance of the fuel cell was justified on the basis of the increase in the electrical conductivity, a diminution in its thermal conductivity and an enhancement of hydrophobicity (surface morphology) of the deposited catalyst layer, when an optimum quantity of epoxy is added to the catalytic ink that makes to improve the mechanical properties of those electrodesAJN and MAG are actually working on this project with a contract funded by the Comunidad Atonoma de la Región de Murcia, Conserjería de Desarrollo Económico, Turismo y Empleo, and the European Union, through the program RIS3- MUR, grant number 2I20SAE00079. This work has also been funded by the Spanish Ministry of Science and Innovation (AEI, Spain,PID2020-112744GB-I00/AEI/10.13039/501100011033 and RTI2018-095844-B-I00), Fundacion Seneca (Región de Murcia, Spain), grant number: 20985/PI/18 and Agencia estatal española de Investigación, grant number PID2019-104272RBC55/AEI/10.13039/501100011033. The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper