Experiential learning of clinical skills by beginning nursing students: "coaching" project by fourth-year student interns

Cutaneous larva migrans is the result of infestation of human skin by helminth larvae, which burrow through the epidermis. This route of infestation makes the foot a typical site for origination of this infection. Children, who frequently play barefoot in locations where the most common of the helminth larvae, the dog and cat hookworms, are endemic, are at particular risk for this disorder. This article reviews the differential diagnosis of cutaneous larva migrans and current concepts in management. Two cases of related children who presented to their pediatricians with this condition are reported.     

Friction-Reducing Surface-Texturing in Reciprocating Automotive Components

A model is presented to study the potential use of micro-surface structure in the form of micro pores to improve tribological properties of reciprocating automotive components. The Reynolds equation and the equation of motion are solved simultaneously for a simplified “piston/cylinder” system with surface texturing. The solution provides the time behavior of both the clearance and the friction force between the “piston ring” and “cylinder liner” surfaces. It is shown that surface texturing can efficiently be used to maintain hydrodynamic effects even with nominally parallel surfaces. It is also shown that optimum surface texturing may substantially reduce the friction losses in reciprocating automotive components.     

CO oxidation over promoted Pt catalysts

A study of CO oxidation by O₂ over Pt catalysts, promoted by MnO_x and CoO_x, is described. The activities of Pt/SiO₂, Pt/MnO_x/SiO₂ and Pt/CoO_x/SiO₂ are compared with commercial Pt/Al₂O₃, Pt/Rh/Al₂O₃ and Pt/CeO_x/Al₂O₃ catalysts. Since these catalysts differ in dispersion and weight loading of platinum, the turnover frequencies are also compared. The following order in activity in CO oxidation after a reductive pretreatment is found: Pt/CoO_x/SiO₂ > Pt/MnO_x/SiO₂, Pt/CeO_x/Al₂O₃ > Pt/Al₂O₃, Pt/Rh/Al₂O₃, Pt/SiO₂. Over Pt/CoO_x/SiO₂ CO is already oxidised at room temperature. Possible models to account for the high activity of Pt/CoO_x/SiO₂ in the CO/O₂ reaction are presented and discussed. Partially reduced metal oxides are necessary to increase the activity of the Pt/CoO_x/SiO₂, Pt/MnO_x/SiO₂ or Pt/CeO_x/Al₂O₃ catalysts. It was shown that mild ageing treatments did not affect the activity of the Pt/CoO_x/SiO₂ catalyst in CO oxidation.     

Digital Control of a Front-End Loader Linkage

A control system for a front-end loader linkage is specified and developed. Using a microcomputer, the controller is capable of positioning the linkage in either Cartesian or angular motion with the ability to store and recall trajectories. The hardware and software used in a scale model, and the typical response of the linkage are shown.     

Further Monte Carlo studies of the rotation-libration transition in solid H2 under pressure

The pressure-induced transition in solid para-H₂ from free rotation of molecules to libration around the three-fold axes of the fcc structure is calculated using a completely anisotropic interaction potential of the form % MathType!MTEF!2!1!+-% feaafiart1ev1aaatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLn% hiov2DGi1BTfMBaeXatLxBI9gBaerbd9wDYLwzYbItLDharqqtubsr% 4rNCHbGeaGqiVu0Je9sqqrpepC0xbbL8F4rqqrFfpeea0xe9Lq-Jc9% vqaqpepm0xbba9pwe9Q8fs0-yqaqpepae9pg0FirpepeKkFr0xfr-x% fr-xb9adbaqaaeGaciGaaiaabeqaamaabaabaaGcbaGaaeOvamaaBa% aaleaacaqGPbGaaeOAaaqabaGccqGH9aqpdaaeqaqaaiaaboeaaSqa% aiaab2gaaeqaniabggHiLdGcdaWgaaWcbaGaaeyBaaqabaGccaGGOa% GaaeOCamaaBaaaleaacaqGPbGaaeOAaaqabaGccaGGPaGaaeywamaa% BaaaleaacaqGYaGaaeyBaaqabaGccaGGOaGaeuyQdC1aaSbaaSqaai% aabMgaaeqaaOGaaiykaiaabMfadaWgaaWcbaGaaeOmaiaab2cacaqG% TbaabeaakiaacIcacqqHPoWvdaWgaaWcbaGaaeOAaaqabaGccaGGPa% aaaa!5132!\[{\text{V}}_{{\text{ij}}} = \sum\nolimits_{\text{m}} {\text{C}} _{\text{m}} ({\text{r}}_{{\text{ij}}} ){\text{Y}}_{{\text{2m}}} (\Omega _{\text{i}} ){\text{Y}}_{{\text{2 - m}}} (\Omega _{\text{j}} )\] including quadrupole-quadrupole and repulsive valence interactions. The rotational part of the Hamiltonian is assumed to be operating on a Jastrow-type wave function, including two variational parameters. The variational integrals are evaluated by a Monte Carlo procedure. The orientational order parameter in the low-density region increases very gradually with increasing density, until a sharp jump (indicating first-order) is observed at the transition density corresponding to R/R ₀ = 0.5775, where R ₀ is the nearest neighbor distance at zero pressure. This is 60% higher than the density obtained in previous work.     

Information processing in low- and high-test-anxious children as a function of grade level and verbal labeling.

Reports results of an investigation of 2nd, 4th, and 6th graders under either game or test conditions. Several implications of attentional theories of test anxiety are reported. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Incorporating agglomeration economies in transport cost-benefit analysis: The case of the proposed light-rail transit in the Tel-Aviv metropolitan area

Abstract.  The economic evaluation of transport projects relies primarily on the impact of the project on road users. Economic benefits are calculated from a reduction in the aggregate value of time saved by the users, as well as from savings on vehicle-operation and maintenance costs, reducion in traffic accidents, and more recently the negative environmental impacts that ensued. Most often the analysis assumes fixed demand. Major mass-transit systems, like the new Light Rail Transit (LRT) currently proposed for the Tel-Aviv Metropolitan Area (TAMA) in Israel, are expected to generate substantial new (induced) traffic. This development will most likely enhance the agglomeration forces at work in major urban concentrations. Agglomeration economies could lead to an upward shift in the production function of the metropolitan area, thus generating substantial additional benefits for the transport project. This article presents the methodology used to estimate the benefits derived from agglomeration economies induced by the aforementioned proposed new LRT in the TAMA. An estimate is made of the increase in the number of employees in the CBD owing to the proposed LRT and their potential contribution to the total annual production of the CBD. Agglomeration economies could add a significant amount of additional benefit to the transport project. In our case study the extent of these benefits increased the benefit-cost ratio from 1.15 to 1.40.     

Hypocholesterolemic effect of lycopene and beta-carotene is related to suppression of cholesterol synthesis and augmentation of LDL receptor activity in macrophages

Beta-Carotene and lycopene are derived from plants, and they share similar initial synthetic pathway with cholesterol, which is synthesized in animal but not in plant cells. Thus, we sought to analyze the effect of carotenoids on macrophage cholesterol metabolism, in comparison to the effect of LDL cholesterol and of the cholesterol synthesis inhibitor, fluvastatin. In J-774 A. 1 macrophage cell line, the cellular cholesterol synthesis from [3H]-acetate, but not from [14C] mevalonate, was suppressed by 63% any by 73% following cell incubation with beta-carotene or lycopene (10 microM) respectively, in comparison to a 90% and 91% inhibition by LDL (100 micrograms of cholesterol), or by fluvastatin (10 micrograms/ml) respectively. However, unlike LDL derived cholesterol, which also suppresses macrophage LDL receptor activity, lycopene and beta-carotene augmented the activity of the macrophage LDL receptor, similarly to the effect of fluvasfatin. In agreement with these in vitro observations, dietary supplementation of tomato's lycopene (60 mg/day) to 6 males for a 3 months period resulted in a significant 14% reduction in their plasma LDL cholesterol concentrations. We thus conclude that dietary supplementation of carotenoids may act as moderate hypocholesterolemic agents, secondary to their inhibitory effect on macrophage 3-hydroxy-3-methyl glutaryl coenzyme A (HMGCoA) reductase, the rate limiting enzyme in cholesterol synthesis.     

Microenvironmental factors regulate Ly-6 A/E expression on PyV-transformed BALB/c 3T3 cells

Ouabain-induced changes of the free cytoplasmic Na+ concentration ([Na+]i) were monitored in aggregates of cells prepared from beta-cell-rich pancreatic mouse islets and the results were compared with the total islet content of sodium. The steady-state [Na+]i was lower in 20 mM glucose (11 mM) than in 3 mM glucose (14 mM). In the presence of 3 mM glucose the addition of 1 mM ouabain resulted in a rise in [Na+]i with an initial rate of 1.5 mM/min. However, the increase of total sodium corresponded to 2.8 mM/min, suggesting that rapid binding and/or sequestration of Na+ are prominent features for pancreatic beta-cells. Elevation of the glucose concentration to 20 mM increased the rate of ouabain-dependent rise of [Na+]i. The effect of glucose was mimicked by 1 mM tolbutamide or 100 microM carbachol and was counteracted by 100 nM of the alpha 2-adrenergic agonist clonidine. Glucose also accelerated the lowering of [Na+]i after withdrawal of ouabain. In promoting not only the entry but also the extrusion of Na+, glucose actually enhances the turnover of the ion in pancreatic beta-cells.