Adaptive high-order finite element solution of transient elastohydrodynamic lubrication problems

This article presents a new numerical method to solve transient line contact elastohydrodynamic lubrication (EHL) problems. A high-order discontinuous Galerkin (DG) finite element method is used for the spatial discretization, and the standard Crank-Nicolson method is employed to approximate the time derivative. An h-adaptivity method is used for grid adaptation with the time-stepping, and the penalty method is employed to handle the cavitation condition. The roughness model employed here is a simple indentation, which is located on the upper surface. Numerical results are presented comparing the DG method to standard finite difference (FD) techniques. It is shown that micro-EHL features are captured with far fewer degrees of freedom than when using low-order FD methods

High voltage planar multijunction solar cell

A high voltage multijunction solar cell is provided wherein a plurality of discrete voltage generating regions or unit cells are formed in a single generally planar semiconductor body. The unit cells are comprised of doped regions of opposite conductivity type separated by a gap or undiffused region. Metal contacts connect adjacent cells together in series so that the output voltages of the individual cells are additive. In some embodiments, doped field regions separated by a overlie the unit cells but the cells may be formed in both faces of the wafer

Method of making a high voltage V-groove solar cell

A method is provided for making a high voltage multijunction solar cell. The cell comprises a plurality of discrete voltage generating regions, or unit cells, which are formed in a single semiconductor wafer and are connected together so that the voltages of the individual cells are additive. The unit cells comprise doped regions of opposite conductivity types separated by a gap. The method includes forming V-shaped grooves in the wafer and thereafter orienting the wafer so that ions of one conductivity type can be implanted in one face of the groove while the other face is shielded. A metallization layer is applied and selectively etched away to provide connections between the unit cells

High voltage v-groove solar cell

A high voltage multijunction solar cell comprises a number of discrete voltage generating regions, or unit cells, which are formed in a single semiconductor wafer and are connected together so that the voltages of the individual cells are additive. The unit cells comprise doped regions of opposite conductivity types separated by a gap. The method includes forming V-shaped grooves in the wafer and orienting the wafer so that ions of one conductivity type can be implanted in one face of the groove while the other face is shielded. A metallization layer is applied and selectively etched away to provide connections between the unit cells

Nutritional and Post-Transplantation Outcomes of Enteral versus Parenteral Nutrition in Pediatric Hematopoietic Stem Cell Transplantation: A Systematic Review of Randomized and Nonrandomized Studies

Hematopoietic stem cell transplantation (HSCT) involves the administration of chemotherapy followed by the infusion of donor stem cells. After treatment, children can consequently experience nausea, vomiting, diarrhea, anorexia, and mucositis, which negatively impact oral intake, leading to rapid deterioration in nutritional status and risk of malnutrition. Nutrition support therefore becomes necessary to circumvent these adverse effects. This has traditionally been provided via parenteral nutrition (PN), but pediatric evidence is increasingly advocating enteral nutrition (EN) as a preferential alternative. The objective of this review is to determine the efficacy of any forms of EN versus PN provided during admission to children aged ≤ 18 years undergoing HSCT. Primary outcomes considered efficacy in relation to various nutritional parameters, and secondary outcomes included a range of post-transplantation parameters. Data sources included English and non-English articles from the start date of MEDLINE, EMBASE, AMED, CINAHL and Cochrane Controlled Trials register, up to July 2018. Key journals were also hand searched, reference lists scanned, clinical experts contacted, and gray literature searched using EThOS and Open Grey. Randomized and observational studies comparing any forms of EN versus PN in children aged ≤ 18 years undergoing HSCT investigating nutritional or post-transplantation outcomes were eligible. Data were extracted from included studies using a custom extraction form that had previously been piloted. Because included studies were observational, risk of bias was assessed using Risk of Bias in Non-randomised Studies of Interventions. Because only a small number of heterogenous studies reporting a wide range of differently defined outcomes were included, meta-analyses were not performed and data were presented in narrative form. Conflicting results in favor of either method of nutrition support or no difference between methods were seen for duration of interventions, nutritional intakes, biochemical and anthropometric changes, mortality, infections, length of admission, and neutrophil engraftment. EN may provide favorable benefits over PN regarding acute graft-versus-host-disease (aGVHD) and platelet engraftment. A paucity of studies was found investigating the question posed by this review. Included studies were clinically heterogenous regarding populations, interventions, and outcomes, at moderate to serious risk of bias due to the absence of randomization, confounding parameters, statistical control, retrospective designs, and participant selection. Some studies were more than 15 years old. Despite the limited number and poor quality of identified studies, results support the growing body of pediatric evidence that EN is feasible during HSCT. Similar differences regarding many nutritional and post-transplantation outcomes were seen in both forms of nutrition support, but EN could provide benefits above PN including reduced incidence of aGVHD and faster platelet engraftment

Secondary prevention of stroke: Using the experiences of patients and carers to inform the development of an educational resource

Copyright @ The Author 2008. This article is available open access through the publisher’s website at the link below.Background. Patients who have had one stroke are at increased risk of another. Secondary prevention strategies that address medical risk factors and promote healthy lifestyles can reduce the risk. However, concordance with secondary prevention strategies is poor and there has been little research into patient and carer views. Objectives. To explore the experiences of patients and carers of receiving secondary prevention advice and use these to inform the development of an educational resource. Methods. A total of 38 participants (25 patients and 13 carers) took part in the study which used an action research approach. Focus groups and interviews were undertaken with patients and carers who had been discharged from hospital after stroke (between 3 and 24 months previously). Framework analysis was used to examine the data and elicit action points to develop an educational resource. Results. Participants’ main concern was their desire for early access to information. They commented on their priorities for what information or support they needed, the difficulty of absorbing complex information whilst still an in-patient and how health professionals’ use of language was often a barrier to understanding. They discussed the facilitators and barriers to making lifestyle changes. The educational resource was developed to include specific advice for medical and lifestyle risk factors and an individual action plan. Conclusion. An educational resource for secondary prevention of stroke was developed using a participatory methodology. Our findings suggest that this resource is best delivered in a one-to-one manner, but further work is needed to identify its potential utility.Peninsula Primary Care Research Networ

Superintegrable models of Winternitz type

A general procedure is outlined which allows one to construct superintegrable models of Winternitz type. Some examples are presented.Comment: 6 pages, LaTeX; To appear in Phys. Lett.