414 research outputs found

    Strategic motivators and expected benefits from e-Commerce in traditional organisations

    Get PDF
    This paper aims to identify the strategic motivators and expected benefits related to the implementation of e-commerce infrastructures in traditional “brick and mortar” organisations. Despite the fact that the clearest benefit from e-commerce might be expected to come from contribution to corporate profits, either from an increase of sales or reduction of costs, but this may not be the case. The literature suggests that there are different ways in which the potential benefits can be assessed. These ways are directly related to the evolution of e-commerce. This research has chosen six representative organisations from different sectors to explore their rationales for their e-commerce strategies. One of the main benefits reported is to increase the focus on the customer and improving internal communications. Additionally, obtaining competitive advantage was found to be a powerful motivator, despite the fact that the recent academic literature suggests that this is very difficult to achieve

    Induced seismicity in pressurised single fractures: a numerical approach

    Get PDF
    The exploration and exploitation of deep geothermal reservoirs has significantly increased during the last years. These reservoirs use heat exchange to produce heat or electricity. The so-called Enhanced Geothermal Systems (EGS) are characterized by a stimulation phase that aims to increase fluid flow and heat transfer between wells by increasing the permeability and transitivity of the reservoir. This is achieved by injecting high-pressure fluids (normally water) in order to increase the apertures of existing fractures, enhancing their sliding and/or generating new ones. However, this technique induces low-magnitude seismicity that occasionally results in damage at the Earth's surface. Numerical simulations able to reproduce the hydro-thermo-mechanical behaviour of geological reservoirs are an essential tool for the evaluation and forecasting of induced seismicity in such systems. In this study, the numerical code CFRAC is used to systematically evaluate how the orientation of faults with respect to the stress field influences seismicity, the injection rate and the fracture sliding behaviour

    3DHIP-Calculator A New Tool to Stochastically Assess Deep Geothermal Potential Using the Heat-In-Place Method from Voxel-Based 3D Geological Models

    Get PDF
    The assessment of the deep geothermal potential is an essential task during the early phases of any geothermal project. The well-known 'Heat-In-Place' volumetric method is the most widely used technique to estimate the available stored heat and the recoverable heat fraction of deep geothermal reservoirs at the regional scale. Different commercial and open-source software packages have been used to date to estimate these parameters. However, these tools are either not freely available, can only consider the entire reservoir volume or a specific part as a single-voxel model, or are restricted to certain geographical areas. The 3DHIP-Calculator tool presented in this contribution is an open-source software designed for the assessment of the deep geothermal potential at the regional scale using the volumetric method based on a stochastic approach. The tool estimates the Heat-In-Place and recoverable thermal energy using 3D geological and 3D thermal voxel models as input data. The 3DHIP-Calculator includes an easy-to-use graphical user interface (GUI) for visualizing and exporting the results to files for further postprocessing, including GIS-based map generation. The use and functionalities of the 3DHIP-Calculator are demonstrated through a case study of the Reus-Valls sedimentary basin (NE, Spain)

    Fluid pressure drops during stimulation of segmented faults in deep geothermal reservoirs

    Get PDF
    Hydraulic stimulation treatments required to produce deep geothermal reservoirs present the risk of generating induced seismicity. Understanding the processes that operate during the stimulation phase is critical for minimising and preventing the uncertainties associated with the exploitation of these reservoirs. It is especially important to understand how the phenomenon of induced seismicity is related to the pressurisation of networks of discrete fractures. In this study, we use the numerical simulator CFRAC to analyse pressure drops commonly observed during stimulation of deep geothermal wells. We develop a conceptual model of a fractured geothermal reservoir to analyse the conditions required to produce pressure drops and their consequences on the evolution of seismicity, fluid pressure, and fracture permeability throughout the system. For this, we combine two fracture sets, one able to be stimulated by shear-mode fracturing and another one able to be stimulated by opening-mode fracturing. With this combination, the pressure drop can be triggered by a seismic event in the shear-stimulated fracture that is hydraulically connected with an opening-mode fracture. Our results indicate that pressure drops are not produced by the new volume created by shear dilatancy, but by the opening of the conjugated tensile fractures. Finally, our results reveal that natural fracture/splay fracture interaction can potentially explain the observed pressure drops at the Rittershoffen geothermal site

    Identifying benefits and barriers for IS adoption : a sociotechnical framework applied to health care

    Get PDF
    The aim of this research is to propose a sociotechnical framework to identify stakeholders involved in information systems and the benefit and barriers to the adoption of such systems. The proposed framework (BEBAF) would help to acknowledge the potential problematic areas for the implementation and adoption of information systems for each actor or social group and to be able to offer solutions based on the potential benefits for each of them. Precursors of BEBAF are social construction of technology (SCOT) and stakeholder identification process. Two case studies in the healthcare contexts, one in the UK and one in Spain, have been conducted in this dissertation using a qualitative approach to provide a rich picture of the influences on e-Health, and the users and organisational response to those influences. Both case studies aimed to support chronically ill patients at home or in nursing homes. BEBAF was then applied to both case studies. Among the most important implications are that those systems hold the promise for improving the quality of life of patients with chronic conditions, providing a better control over the disease. However, their impact on the organisational structures, the lack of funding and the difficulties of alignment of all the actors involved are relevant constraints to their adoption into the mainstream healthcare services. The main contributions of this thesis are: first, the definition and evaluation of a socio-technical framework to investigate IS adoption. Apart from the two closure mechanisms proposed by SCOT, BEBAF proposes a new closure mechanism by reinterpretation of benefits. In turn, the application of the framework has led to identify an extensive list of barriers and benefits for the adoption of e-Health systems with some suggested solutions. Another outcome is a comprehensive list of stakeholders involved in the adoption of such systems.EThOS - Electronic Theses Online ServiceGBUnited Kingdo

    Tamizaje de salud mental mediante el test M.I.N.I. en estudiantes del ciclo básico de medicina de la Universidad Nacional de Asunción

    Get PDF
    INTRODUCCIÓN: Los estudiantes de medicina están expuestos a un mayor número de trastornos mentales que los de la población general por las exigencias propias de la carrera, resaltan entre estos trastornos los de ansiedad y depresión cuyos valores son superiores a los encontrados en la población general. La Mini International Neuropsychiatric Interview (MINI) es una entrevista breve y altamente estructurada de los principales trastornos psiquiátricos del CIE-10. MATERIALES Y MÉTODOS: Fue un estudio observacional analítico con corte transversal realizado en la Facultad de Ciencias Médicas de la Universidad Nacional de Asunción (UNA). Las variables epidemiológicas y sociodemográficas fueron recolectadas con un formulario previamente validado. Se evaluó la frecuencia de trastornos de salud mental en los alumnos utilizando el test MINI, validado en español, como método de tamizaje. RESULTADOS: Se evaluó 91 estudiantes, 58 del sexo femenino (63,7%) y 33 de sexo masculino (36,3%); la media de la edad fue de 21 ± 1 años; 35 alumnos (58,2%) tuvieron al menos un trastorno mental. Los diagnósticos más frecuentes fueron: episodio hipomaniaco pasado (21 alumnos; 23,1%), trastorno depresivo actual (21; 23,1%), trastorno de ansiedad generalizada (15; 16,5%) y agorafobia (14; 15,4%). DISCUSIÓN: los problemas de salud mental fueron frecuentes en la población universitaria que estudiamos siendo el episodio hipomaniaco pasado, el episodio depresivo mayor actual, el trastorno de ansiedad generalizada y la agorafobia, los problemas más frecuentes

    Overlap at the molecular and immunohistochemical levels between angioimmunoblastic T-cell lymphoma and a subgroup of peripheral T-cell lymphomas without specific morphological features

    Get PDF
    The overlap of morphology and immunophenotype between angioimmunoblastic T-cell lymphoma (AITL) and other nodal peripheral T-cell lymphomas (n-PTCLs) is a matter of current interest whose clinical relevance and pathogenic background have not been fully established. We studied a series of 98 n-PTCL samples (comprising 57 AITL and 41 PTCL-NOS) with five TFH antibodies (CD10, BCL-6, PD-1, CXCL13, ICOS), looked for mutations in five of the genes most frequently mutated in AITL (TET2, DNMT3A, IDH2, RHOA and PLCG1) using the Next-Generation-Sequencing Ion Torrent platform, and measured the correlations of these characteristics with morphology and clinical features. The percentage of mutations in the RHOA and TET2 genes was similar (23.5% of cases). PLCG1 was mutated in 14.3%, IDH2 in 11.2% and DNMT3A in 7.1% of cases, respectively. In the complete series, mutations in RHOA gene were associated with the presence of mutations in IDH2, TET2 and DNMT3A (p < 0.001, p = 0.043, and p = 0.029, respectively). Fourteen cases featured RHOA mutations without TET2 mutations. A close relationship was found between the presence of these mutations and a TFH-phenotype in AITL and PTCL-NOS patients. Interestingly, BCL-6 expression was the only TFH marker differentially expressed between AITL and PTCL-NOS cases. There were many fewer mutated cases than there were cases with a TFH phenotype. Overall, these data suggest alternative ways by which neoplastic T-cells overexpress these proteins. On the other hand, no clinical or survival differences were found between any of the recognized subgroups of patients with respect to their immunohistochemistry or mutational profile.This work was supported by grants from the Instituto de Salud Carlos III, from the Ministerio de Economía, Industria y Competitividad (RTICC RD06/0020/0107, RD12/0036/0060, PI 12/1682, PT13/0010/0007, PI16/ 01294, SAF2013-47416-R, CIBERONC-ISCIII, PIE15/ 0081, ISCIII-MINECO AES-FEDER (Plan Estatal I+D+I 2013–2016): PI14/00221, PIE14/0064, PIE15/0081 and PIE16/01294)) and the Asociación Española Contra el Cáncer, Spain. JG-R is a recipient of an iPFIS predoctoral fellowship (IFI14/00003) from ISCIII-MINECO-AESFEDER (Plan Estatal I+D+I 2013–2016). MSB was supported by a Miguel Servet contract (CP11/00018) from the ISCIII-MINECO-AES-FEDER (Plan Nacional I+D+I 2008–2011), and currently holds a Miguel Servet II contract (CPII16/00024), supported by ISCIII-MINECOAES- FEDER (Plan Estatal I+D+I 2013–2016) and the Fundación de Investigación Biomédica Puerta de Hierro.S

    Testing one-body density functionals on a solvable model

    Full text link
    There are several physically motivated density matrix functionals in the literature, built from the knowledge of the natural orbitals and the occupation numbers of the one-body reduced density matrix. With the help of the equivalent phase-space formalism, we thoroughly test some of the most popular of those functionals on a completely solvable model.Comment: Latex, 16 pages, 4 figure

    Detection and dynamics of circulating tumor cells in patients with high-risk prostate cancer treated with radiotherapy and hormones: a prospective phase II study

    Get PDF
    BACKGROUND: Circulating tumor cells (CTCs) are an established prognostic marker in castration-resistant prostate cancer but have received little attention in localized high-risk disease. We studied the detection rate of CTCs in patients with high-risk prostate cancer before and after androgen deprivation therapy and radiotherapy to assess its value as a prognostic and monitoring marker. PATIENTS AND METHODS: We performed a prospective analysis of CTCs in the peripheral blood of 65 treatment-naive patients with high-risk prostate cancer. EpCAM-positive CTCs were enumerated using the CELLSEARCH system at 4 timepoints. A cut off of 0 vs >/= 1 CTC/7.5 ml blood was defined as a threshold for negative versus positive CTCs status. RESULTS: CTCs were detected in 5/65 patients (7.5%) at diagnosis, 8/62 (12.9%) following neoadjuvant androgen deprivation and 11/59 (18.6%) at the end of radiotherapy, with a median CTC count/7.5 ml of 1 (range, 1-136). Only 1 patient presented a positive CTC result 9 months after radiotherapy. Positive CTC status (at any timepoint) was not significantly associated with any clinical or pathologic factors. However, when we analyzed variations in CTC patterns following treatment, we observed a significant association between conversion of CTCs and stages T3 (P = 0.044) and N1 (P = 0.002). Detection of CTCs was not significantly associated with overall survival (P > 0.40). CONCLUSIONS: Our study showed a low detection rate for CTCs in patients with locally advanced high-risk prostate cancer. The finding of a de novo positive CTC count after androgen deprivation therapy is probably due to a passive mechanism associated with the destruction of the tumor. Further studies with larger samples and based on more accurate detection of CTCs are needed to determine the potential prognostic and therapeutic value of this approach in non-metastatic prostate cancer. TRIAL REGISTRATION: ClinicalTrials.gov ID: NCT01800058
    corecore