A control chart procedure for student grade monitoring

This article reports an application of the control chart procedure for monitoring award of grades to students by the teaching staff in a large university. The chart procedure signals the presence of special cause variations if any in the award of grades. Implementation of the grade monitoring procedure saved considerable time and effort while ensuring that the reported special cause situations are justified. The mathematical derivations for the new control chart scheme are also presented

IMPROVED CORROSION RESISTANCE OF FRICTION STIR ZONE OF RARE EARTH MAGNESIUM ALLOY AE42

Corrosion studies on friction stir welded AE42 magnesium alloy were carried out in 0.1 M ammonium carbonate solution. For better understanding, comparative analysis of corrosion rates was carried out before and after welding. Friction stir weld zone was more corrosion resistant than the parent metal under similar experimental conditions. Grain size was refined at weld zone. Second phase intermetallic particles were refined into tiny pieces of 1-2 micron size and evenly distributed throughout the matrix. Local electrochemical imbalance was eliminated due to the grain refinement and elimination of continuous grain boundary. These phenomena improved the corrosion resistance of weld zone. Scanning electron microscopic images confirmed mild and uniform corrosion of weld zone and rigorous inhomogeneous corrosion of parent metal

Slider User Interface with Precise Value Selection Using Gestures

Sliders are user interface elements that enable users to view and select values from a predefined range along a horizontal or vertical bar. Values on a slider are usually incremented with preset multipliers. When a user wants to select a value that requires precision that is not supported by the preset multipliers, the user is not able to achieve the desired accuracy. Such limitations are due to the limited amount of physical space and/or touch sensitivity available for interactions such as tapping or swiping. This disclosure describes a slider user interface that enables users to fine tune value selection using finger interactions (or equivalent) without requiring the use of a keyboard or other auxiliary mechanism. Per the techniques, the user can grab the slider knob (e.g., via touch and hold) and drag it at different angles to access multipliers with different levels of precision. The distance from the initial position is used to determine the selected value

Modelling the Role of Active Biomass on the Fate and Transport of a Heavy Metal in the Presence of Root Exudates

The influence of active biomass in immobilizing heavy metals in the soil rhizosphere is investigated through mechanistic models. The movement of water in the soil is modeled using Richards equation. An advection-dispersion equation, with a sink term for metal uptake by biomass, is used for modeling the fate and transport of lead. This sink term represents the nonlinear kinetics of metal adsorption to the biomass that is partitioned into mobile and stationary fractions within the soil. Transport of the mobile biomass fraction is modeled by an advection-dispersion equation, with a source term that is based on Monod growth kinetics, and a linear sink term for endogenous decay. The movement of metal in association with mobile biomass is also included as a transport mechanism for lead. Root exudates serve as carbon substrate for the biomass growth, and their transport is modeled in a similar way as that of the biomass. A hypothetical one-dimensional vertical soil column containing metal, biomass and a carbon substrate is used for analyzing lead movement. Model simulations demonstrate the influence of water content, growth rate of biomass, partitioning coefficient of biomass between soil and aqueous phase, and partitioning coefficient of metal between biomass and aqueous phase of the soil on fate and transport of lead. The extent of immobilization of lead in soil is found to be dependent on the growth of biomass, which in turn depends on the availability of root exudates in the rhizosphere. Apart from analyzing different scenarios, such a model can be used for designing future experiments

Tension Subdural Hygroma Following Resection of Posterior Fossa Tumour in a Child: A new clinico-radio-pathological entity

Persistent hydrocephalus is common in child after resection of posterior fossa tumours. Occurrence of subdural hygroma, but is very rare, with only few cases reported. We report the rare case of a child who developed a tense subdural hygroma with stable hydrocephalus, in the early postoperative period, following posterior fossa tumour resection. We describe the distinctive clinical, radiological and pathological features associated with the development of a tense subdural hygroma.  We also discuss the management by cerebrospinal fluid diversion, which includes either a ventriculoperitoneal or subduroperitoneal shunt. This unique condition is distinguished from external hydrocephalus by features that are critical to the management strategy.  Keywords: Child, Posterior fossa tumour, Postoperative period, Hydrocephalus, Subdural hygroma, Hygroma, External hydrocephalus

Downer cows: a reanalysis of an old data set.

CAUL Read and Publish Agreement.AIMS: To compare the performance of two predictive models for the survival of downer cows. METHODS: The first model had been developed in 1987 using a dataset containing missing values, while the second, new model was developed on the same dataset but using modern data imputation and analytical methods. Missing data were imputed using multiple imputation by chained equations and a logistic regression model fitted to the imputed data, with survival or not as the outcome variable. The predictive ability of the model built on the imputed data was contrasted with the original prognostic model by testing them both on a second smaller but complete data set, collected contemporaneously with the development of the original model but from a different region of New Zealand. Sensitivity, specificity, accuracy, and cut point for the two models were calculated. RESULTS: The original 1987 model had a slightly higher accuracy than that of the new one with a sensitivity of 0.85 (95% CI = 0.72-0.94) and a specificity of 0.82 (95% CI = 0.7-0.91), using a cut point for the probability of survival = 0.313. CONCLUSIONS: The original prognostic formula published by Clark et al. in 1987 performed as well as a modern model built on an imputed data set. CLINICAL RELEVANCE: The use of a prognostic test based on the Clark model should remain an important part of the clinical examination of downer cows by New Zealand veterinarians.Abbreviations: AUC: Area under the curve; AST: Aspartate transaminase activity; CK: Creatine phosphokinase activity; GAM: Generalised additive model; NSAID: Non-steroidal-anti-inflammatory drugs; PCV: Packed cell volume.Publishe

Anti-Herpes Simplex Virus (HSV-1 and HSV-2) activity of biogenic gold and silver nanoparticles using seaweed Sargassum wightii

1252-1257Biogenic gold (Au) and silver (Ag) nanoparticles were synthesized using seaweed Sargassum wightii (Sw) and their antiviral activity against Herpes Simplex Virus (HSV-1 and HSV-2) was evaluated. Efficacy of Sw-Au and Sw-Ag nanoparticles against HSV was estimated by the reduction of cytopathic effect (CPE) caused by HSV, which was observed in a dose-dependent manner. Sw-Au nanoparticles reduced 70% CPE of HSV-1 and HSV-2 at 10 μL and 25 μL, respectively, whereas 2.5 μL Sw-Ag nanoparticles effectively reduced 70% CPE of HSV-1 and HSV-2. Cytotoxicity was estimated in Vero cells by MTT assay. Sw-Au nanoparticles were significantly non-toxic in all the concentrations tested, whereas Sw-Ag nanoparticles were found to be toxic in higher concentrations. Sw-Au nanoparticles showed cell viability of 93.12-85.18 % in the range of 2.5-25 µL, and Sw-Ag nanoparticles showed cell viability of 97.21-21.91% in the range of 1-10 μL. Sw-Au and Sw-Ag nanoparticles effectively reduce the CPE caused by both HSV-1 and HSV-2 in Vero cells and can be used to treat HSV infections