Equivalent layered models for functionally graded plates

Functionally graded plates whose material properties vary continuously through the thickness are modelled as exactly equivalent plates composed of up to four isotropic layers. Separate models are derived for analysis using classical plate theory, first-order and higher-order shear deformation theory. For cases where Poisson’s ratio varies through the thickness, the integrations required to obtain the membrane, coupling and out-of-plane stiffness matrices are performed accurately using a series solution. The model is verified by comparison with well converged solutions from approximate models in which the plate is divided into many isotropic layers. Critical buckling loads and undamped natural frequencies are found for a range of illustrative examples

The impact of resources on decision making

Decision making is a significant activity within industry and although much attention has been paid to the manner in which goals impact on how decision making is executed, there has been less focus on the impact decision making resources can have. This article describes an experiment that sought to provide greater insight into the impact that resources can have on how decision making is executed. Investigated variables included the experience levels of decision makers and the quality and availability of information resources. The experiment provided insights into the variety of impacts that resources can have upon decision making, manifested through the evolution of the approaches, methods, and processes used within it. The findings illustrated that there could be an impact on the decision-making process but not on the method or approach, the method and process but not the approach, or the approach, method, and process. In addition, resources were observed to have multiple impacts, which can emerge in different timescales. Given these findings, research is suggested into the development of resource-impact models that would describe the relationships existing between the decision-making activity and resources, together with the development of techniques for reasoning using these models. This would enhance the development of systems that could offer improved levels of decision support through managing the impact of resources on decision making

A pivotal year for Bolivian conservation policy

Non peer reviewe

Three-dimensional power Doppler angiography in endometrial cancer: correlation with tumor characteristics

To assess the correlation between intratumoral vascularization using three-dimensional power Doppler angiography (3D-PDA) and several histological tumor characteristics in a series of patients with endometrial carcinoma. METHODS: Ninety-nine women (mean age, 61.7 (range, 31-84) years) diagnosed as having endometrial cancer were assessed by transvaginal 3D-PDA before surgical staging. Endometrial volume (EV) and 3D-PDA vascular indices (vascularization index (VI), flow index (FI) and vascularization flow index (VFI)) were calculated using the Virtual Organ Computer-aided AnaLysis (VOCAL) method. All patients were surgically staged. Individual tumor features such as histological type, tumor grade, myometrial infiltration depth, lymph-vascular space involvement, cervical involvement, lymph node metastases and tumor stage were considered for analysis. Multivariate logistic regression (MLR) analysis was used to determine which 3D-PDA parameters were independently associated with each histological characteristic. RESULTS: MLR analysis showed that only EV and VI were independently associated with myometrial infiltration (EV: odds ratio (OR), 1.119 (95% CI, 1.025-1.221), P = 0.012; VI: OR, 1.127 (95% CI, 1.063-1.195), P = 0.001) and tumor stage (EV: OR, 1.103 (95% CI, 1.012-1.202), P = 0.025; VI: OR, 1.120 (95% CI, 1.057-1.187), P = 0.001), only VI was independently associated with tumor grade (OR, 1.056 (95% CI, 1.023-1.091), P = 0.001) and only EV was independently associated with lymph node metastases (OR, 1.086 (95% CI, 1.017-1.161), P = 0.001). CONCLUSION: 3D-PDA analysis of tumor vascularization in endometrial cancer correlates with some prognostic histological characteristics

Estudios térmicos sobre minerales de interés metalúrgico. V. Cinética de la descomposición térmica de crisocola y brocantita, y estudio mineralógico

The thermal decomposition process of chrysocoUa mineral and a copper hidroxysulfate is studied in this work by TGA, DTA and powder X-ray diffraction. Several data on reaction orders and activation energies valúes, as well as X-ray data are reported.Se ha estudiado el proceso de descomposición térmica de dos oxisales de cobre, una natural, crisocola, y otra sintética, brocantita, mediante termogravimetría, análisis térmico diferencial y difracción de rayos X. Se ofrecen datos sobre los valores de orden de reacción y energía de activación correspondiente a los procesos de deshidratación, así como de difractometría de polvo

DNA double-strand breaks cooperate with loss of Ink4 and Arf tumor suppressors to generate glioblastomas with frequent Met amplification

Glioblastomas (GBM) are highly radioresistant and lethal brain tumors. Ionizing radiation (IR)- induced DNA double-strand breaks (DSBs) are a risk factor for the development of GBM. In this study, we systematically examined the contribution of IR-induced DSBs to GBM development using transgenic mouse models harboring brain-targeted deletions of key tumor suppressors frequently lost in GBM, namely Ink4a, Ink4b, Arf, and/or PTEN. Using low linear energy transfer (LET) X-rays to generate simple breaks or high LET Fe ions to generate complex breaks, we found that DSBs induce high-grade gliomas in these mice which, otherwise, do not develop gliomas spontaneously. Loss of Ink4a and Arf was sufficient to trigger IR-induced glioma development but additional loss of Ink4b significantly increased tumor incidence. We analyzed IR-induced tumors for copy number alterations (CNAs) to identify oncogenic changes that were generated and selected for as a consequence of stochastic DSB events. We found Met amplification to be the most significant oncogenic event in these radiation-induced gliomas. Importantly, Met activation resulted in expression of Sox2, a GBM cancer stem cell (CSC) marker, and was obligatory for tumor formation. In sum, these results indicate that radiation-induced DSBs cooperate with loss of Ink4 and Arf tumor suppressors to generate high-grade gliomas that are commonly driven by Met amplification and activation

Surgical checklist: seeking the involvement of professionals and patients

Objetivos: Los objetivos fueron mejorar la adherencia al listado de verificación quirúrgica (LVQ), identificar barreras y reclamar el apoyo de profesionales y pacientes. Material y Métodos: Se registró la participación en el proyecto PaSQ-WP5/ LVQ entre 2013 y 2015: Plan de Acción con dos líneas de trabajo, dirigidas a profesionales y pacientes, que contemplaban rondas de evaluación, análisis de barreras, evaluación de percepción del listado mediante cuestionarios de la Hauté Autorité de Santé, formación en seguridad y diseño del folleto Cirugía Segura Salva Vidas. Resultados: Los datos de presencia del LVQ en la historia clínica reflejaron una mejora estadísticamente significativa respecto a los iniciales. En 68,2% de las rondas se cumplimentó el listado correctamente. La opinión del profesional sobre la utilidad del listado fue positiva en 79,8% y consideró que había ayudado a identificar e interceptar incidentes de seguridad en 25,6%. Sin embargo, resultó difícil de aplicar durante urgencias quirúrgicas (51,8%), al enfermero le costó gestionar el listado (59,5%) y el intercambio de información en voz alta se interrumpió con frecuencia (51,2%). Del análisis de barreras destacaron el sobre-registro, falta de liderazgo del gestor del listado, escasa implicación de facultativos y ausencia de trabajo en equipo. Conclusiones: La implantación del LVQ fue laboriosa pero la implicación de profesionales y pacientes ayudó a avanzar en la cultura de seguridad. La actitud general de los sanitarios es positiva y por tanto no se trata de imponer el uso obligatorio del LVQ, sino de convencer de que su cumplimiento reduce los eventos adversos evitables.Objectives: To improve the adhesion to the surgical safety checklist (SSC), identify barriers and claim the support of professionals and patients. Methods: The experience includes our participation in the Pasq-WP5 / SSC project, directed to surgical professionals and patients. An Action Plan was developed from 2013 to 2015 with two lines of work, one for professionals and other for patients; whose activities are: evaluation rounds, barrier analysis, evaluation SSC perception (using Hauté Autorité de Santé questionnaires), safety training and brochure design Safe Surgery Saves Lives. Results: Data of SSC in the medical record reflect a statistically significant improvement. In 68.2% of the rounds, SSC was filled in correctly. Professional opinion on the usefulness of SSC is positive in 79.8%; consider that it is difficult to apply in emergency in 51.8%, it is difficult for a nurse to manage the SSC in 59.5%, the exchange of information aloud is difficult to obtain in 51.2% and the SSC has helped identify and intercept security incidents 25.6%. Analysis of barriers includes the over-registration, lack of leadership SSC manager, limited involvement of doctors and lack of teamwork. Conclusions: The involvement of professionals and patients will help further progress in safety culture. The goal is not to impose the SSC, but convinced that compliance reduce preventable adverse events

Management of a ruptured epidural catheter, an anesthesiologist's dilemma: a case report

Epidural anesthesia is a widely used anesthetic technique in lower extremity surgeries although it is a relatively safe procedure, it can have complications, such as rupture of the epidural catheter. This is a 69-year-old male patient with a diagnosis of Wagner IV diabetic foot is presented, which was scheduled for left supracondylar amputation in which after epidural block, retention of the catheter tip in the epidural space at level L2-L3 was seen, so hemi laminectomy was performed in a second surgical stage in L2 and removal of the epidural catheter. Ideally a broken needle should be removed as soon as possible