Incorporación de la gestión del riesgo de desastres a la educación gerencial: el caso de Mona School of Business & Management

The purpose of this paper is to provide a background to and guide for mainstreaming Disaster Risk Management (DRM) into higher education and training institutions in Small Island Developing States (SIDS), with the aim of increasing awareness and understanding of the complexity of DRM issues in business and management, based on their general and specific vulnerabilities. SIDS are considered a special category within the discussion on DRM, given a number of vulnerabilities generally and specifically. Furthermore, little attention has been paid to the business impact of disasters in such settings. It is proposed that one major route to improving this situation is through the educational and training institutions, which play a major role in shaping thinking and practices in such settings.El propósito de este artículo es proveer un contexto y guiar en la incorporación de la Gestión del Riesgo de Desastres (GRD) en las instituciones de educación superior y de formación en los Pequeños Estados Insulares en Desarrollo (PEID) con el propósito de aumentar el nivel de consciencia y comprensión sobre la complejidad de los asuntos relacionados con GRD en los negocios y la administración, teniendo como base vulnerabilidades generales y específicas. LOS PEID son considerados una categoría especial dentro de la discusión sobre GRD debido a la cantidad de vulnerabilidades generales y específicas con las que cuentan. Se propone que una de las principales rutas para mejorar esta situación es a través de las instituciones educativas y de formación, quienes desempeñan un papel importante en la conformación del pensamiento y las prácticas de aquellos entornos

Models of in vitro spermatogenesis

Understanding the mechanisms that lead to the differentiation of male germ cells from their spermatogonial stem cells through meiosis to give rise to mature haploid spermatozoa has been a major quest for many decades. Unlike most other cell types this differentiation process is more or less completely dependent upon the cells being located within the strongly structured niche provided by mature Sertoli cells within an intact seminiferous epithelium. While much new information is currently being obtained through the application and description of relevant gene mutations, there is still a considerable need for in vitro models with which to explore the mechanisms involved. Not only are systems of in vitro spermatogenesis important for understanding the basic science, they have marked pragmatic value in offering ex vivo systems for the artificial maturation of immature germ cells from male infertility patients, as well as providing opportunities for the transgenic manipulation of male germ cells. In this review, we have summarized literature relating to simplistic culturing of germ cells, co-cultures of germ cells with other cell types, especially with Sertoli cells, cultures of seminiferous tubule fragments, and briefly mention the opportunities of xenografting larger testicular pieces. The majority of methods are successful in allowing the differentiation of small steps in the progress of spermatogonia to spermatozoa; few tolerate the chromosomal reduction division through meiosis, and even fewer seem able to complete the complex morphogenesis which results in freely swimming spermatozoa. However, recent progress with complex culture environments, such as 3-d matrices, suggest that possibly success is now not too far away

Towards a Big Data system disaster recovery in a Private Cloud

Disaster recovery (DR) plays a vital role in restoring the organization's data in the case of emergency and hazardous accidents. While many papers in security focus on privacy and security technologies, few address the DR process, particularly for a Big Data system. However, all these studies that have investigated DR methods belong to the “single-basket” approach, which means there is only one destination from which to secure the restored data, and mostly use only one type of technology implementation. We propose a “multi-purpose” approach, which allows data to be restored to multiple sites with multiple methods to ensure the organization recovers a very high percentage of data close to 100%, with all sites in London, Southampton and Leeds data recovered. The traditional TCP/IP baseline, snapshot and replication are used with their system design and development explained. We compare performance between different approaches and multi-purpose approach stands out in the event of emergency. Data at all sites in London, Southampton and Leeds can be restored and updated simultaneously. Results show that optimize command can recover 1 TB of data within 650 s and command for three sites can recover 1 TB of data within 1360 s. All data backup and recovery has failure rate of 1.6% and below. All the data centers should adopt multi-purpose approaches to ensure all the data in the Big Data system can be recovered and retrieved without experiencing a prolong downtime and complex recovery processes. We make recommendations for adopting “multi-purpose” approach for data centers, and demonstrate that 100% of data is fully recovered with low execution time at all sites during a hazardous event as described in the paper

Rapid Microwave Preparation of Thermoelectric TiNiSn and TiCoSb Half-Heusler Compounds

The 18-electron ternary intermetallic systems TiNiSn and TiCoSb are promising for applications as high-temperature thermoelectrics and comprise earth-abundant, and relatively nontoxic elements. Heusler and half-Heusler compounds are usually prepared by conventional solid state methods involving arc-melting and annealing at high temperatures for an extended period of time. Here, we report an energy-saving preparation route using a domestic microwave oven, reducing the reaction time significantly from more than a week to one minute. A microwave susceptor material rapidly heats the elemental starting materials inside an evacuated quartz tube resulting in near single phase compounds. The initial preparation is followed by a densification step involving hot-pressing, which reduces the amount of secondary phases, as verified by synchrotron X-ray diffraction, leading to the desired half-Heusler compounds, demonstrating that hot-pressing should be treated as part of the preparative process. For TiNiSn, high thermoelectric power factors of 2 mW/mK^2 at temperatures in the 700 to 800 K range, and zT values of around 0.4 are found, with the microwave-prepared sample displaying somewhat superior properties to conventionally prepared half-Heuslers due to lower thermal conductivity. The TiCoSb sample shows a lower thermoelectric figure of merit when prepared using microwave methods because of a metallic second phase

Surfactant-Free Synthesis of Bi_(2)Te_(3)-Te Micro-Nano Heterostructure with Enhanced Thermoelectric Figure of Merit

An ideal thermoelectric material would be a semiconductor with high electrical conductivity and relatively low thermal conductivity: an “electron crystal, phonon glass”. Introducing nanoscale heterostructures into the bulk TE matrix is one way of achieving this intuitively anomalous electron/phonon transport behavior. The heterostructured interfaces are expected to play a significant role in phonon scattering to reduce thermal conductivity and in the energy-dependent scattering of electrical carriers to improve the Seebeck coefficient. A nanoparticle building block assembly approach is plausible to fabricate three-dimensional heterostructured materials on a bulk commercial scale. However, a key problem in applying this strategy is the possible negative impact on TE performance of organic residue from the nanoparticle capping ligands. Herein, we report a wet chemical, surfactant-free, low-temperature, and easily up-scalable strategy for the synthesis of nanoscale heterophase Bi_(2)Te_(3)-Te via a galvanic replacement reaction. The micro-nano heterostructured material is fabricated bottom-up, by mixing the heterophase with commercial Bi_(2)Te_3. This unique structure shows an enhanced zT value of ~0.4 at room temperature. This heterostructure has one of the highest figures of merit among bismuth telluride systems yet achieved by a wet chemical bottom-up assembly. In addition, it shows a 40% enhancement of the figure of merit over our lab-made material without nanoscale heterostructures. This enhancement is mainly due to the decrease in the thermal conductivity while maintaining the power factor. Overall, this cost-efficient and room temperature synthesis methodology provides the potential for further improvement and large-scale thermoelectric applications

Silicon-Based Thermoelectrics Made from a Boron-Doped Silicon Dioxide Nanocomposite

We report a method for preparing p-type silicon germanium bulk alloys directly from a boron-doped silica germania nanocomposite. This is the first successful attempt to produce and characterize the thermoelectric properties of SiGe-based thermoelectric materials prepared at temperatures below the alloy’s melting point through a magnesiothermic reduction of the silica-germania nanocomposite. We observe a thermoelectric power factor that is competitive with the literature record obtained for high energy ball milled nanocomposites. The large grain size in our hot pressed samples limits the thermoelectric figure of merit to 0.5 at 800 °C for an optimally doped Si_(80)Ge_(20) alloy