Leading logarithm calculation of the e^+ e^- -> e^+ \nu_e \bar{u} d cross section

We analytically evaluate in the leading logarithm approximation the differential cross section for e^+ e^- -> e^+ \nu_e \bar{u} d. We compare our order \alpha^4 \alpha_s^0 leading-log result to the order \alpha^4 \alpha_s^0 exact result obtained from the GRC4F Monte Carlo program. Finally we use the Gluck, Reya, Schienbien distribution of partons in a virtual photon, which incorporates both evolution and nonperturbative strong interaction contributions, to obtain better estimates of the differential cross section.Comment: 10 pages including 9 figure

Prospects of pulsed amperometric detection in flow-based analytical systems: a review

Electrochemical (EC) detection techniques in flow-based analytical systems such as flow injection analysis (FIA), capillary electrophoresis (CE), and liquid chromatography (LC) have attracted continuous interest over the last three decades, leading to significant advances in EC detection of a wide range of analytes in the liquid phase. In this context, the unique advantages of pulsed amperometric detection (PAD) in terms of high sensitivity and selectivity, and electrode cleaning through the application of pulsed potential for noble metal electrodes (e.g. Au, Pt), have established PAD as an important detection technique for a variety of electrochemically active compounds. PAD is especially valuable for analytes not detectable by ultraviolet (UV) photometric detection, such as organic aliphatic compounds and carbohydrates, especially when used with miniaturised capillary and chip-based separation methods. These applications have been accomplished through advances in PAD potential waveform design, as well as through the incorporation of nanomaterials (NMs) employed as microelectrodes in PAD. PAD allows on-line pulsed potential cleaning and coupling with capillary or standard separation techniques. The NMs are largely employed in microelectrodes to speed up mass and electron transfer between electrode surfaces and to perform as reactants in EC analysis. These advances in PAD have improved the sensitive and selective EC detection of analytes, especially in biological samples with complex sample matrices, and detection of electro-inactive compounds such as aliphatic organic compounds (i.e., formic acid, acetic acid, maleic acids, and β-cyclodextrin complexes). This review addresses the fundamentals of PAD, the role of pulsed sequences in AD, the utilization of different EC detectors for PAD, technological advancements in PAD waveforms, utilisation of microelectrodes in PAD techniques, advances in the use of NMs in PAD, the applications of PAD, and prospects for EC detection, with emphasis on PAD in flow-based systems

Multivariate analysis of the effects of age, particle size and landfill depth on heavy metals pollution content of closed and active landfill precursors

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Multivariate analysis of a heavy metal pollution survey of closed and active landfill precursors was carried out in order to compare environmental risk levels in relation to age, particle size and depth of the precursors. Landfill precursors (77) were collected and analyzed for 15 USEPA toxic heavy metals using ICP-MS. Heavy metals concentrations in closed landfill precursors were significantly higher than those in the active landfill for 11 of 15 heavy metals investigated (closed landfill order: Fe > Al > Mn > Cu > Pb > Ba> Co > Cr > Ni > Cd > As > Se > Ti). Cluster analysis and correlation studies indicated the distribution of the metals was more influenced by landfill precursor size than by depth of the sample. Principal component analysis (PCA) showed that 10 of 15 of heavy metals of both landfill precursors were from similar anthropogenic sources. Heavy metals pollution indices (Igeo > 5, EF > 40 and CF > 7) of both active and closed landfill precursors exceeded limits in the order of Zn > Cd > Pb > Cu > Ag, indicating a major potential health risk influenced by age and particle size of precursor. Zn, Cd, Cu and Pb of both landfill precursors exceeded the USEPA set standard for assessment of human health risk for each of the metals (1×10 -4 to 1× 10-3). This study highlights the need for the integration of a clean-up process for precursors from both types of landfill to reduce possible environmental pollution during a reuse process

Conversion of solid waste to activated carbon to improve landfill sustainability

The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Landfills’ heterogeneous composites waste were evaluated as precursors for generation of activated carbon (AC). A single step chemical activation process was applied involving irradiation with microwave energy and impregnation with KOH. The average percentage yield of AC from active landfill precursor was higher than that from closed landfill for all depths sampled. Increase in impregnation ratio and irradiation power decreased the average percentage yield for both landfill precursors (Active: 38.1 to 33.1%) (Closed 42.1: to 33.3%). The optimum pH range for adsorption of methylene blue was pH 6-7, while adsorption increased with increase in temperature over the range 30 to 50oC. Carbonyl and hydroxyl groups were the major functional groups on the surface of AC. The properties of the AC are potentially suitable for the removal of cationic dyes and pollutants. AC generated from the landfill composite were comparable to that from some other biomass being managed through AC generation. This is the first report to demonstrate the possible reuse of landfill composite as AC. The reuse option of landfill composite could provide a means of sustainable management of landfilled municipal waste

A Sweet Recipe for Consolidated Vulnerabilities: Attacking a Live Website by Harnessing a Killer Combination of Vulnerabilities

The recent emergence of new vulnerabilities is an epoch-making problem in the complex world of website security. Most of the websites are failing to keep updating to tackle their websites from these new vulnerabilities leaving without realizing the weakness of the websites. As a result, when cyber-criminals scour such vulnerable old version websites, the scanner will represent a set of vulnerabilities. Once found, these vulnerabilities are then exploited to steal data, distribute malicious content, or inject defacement and spam content into the vulnerable websites. Furthermore, a combination of different vulnerabilities is able to cause more damages than anticipation. Therefore, in this paper, we endeavor to find connections among various vulnerabilities such as cross-site scripting, local file inclusion, remote file inclusion, buffer overflow CSRF, etc. To do so, we develop a Finite State Machine (FSM) attacking model, which analyzes a set of vulnerabilities towards the road to finding connections. We demonstrate the efficacy of our model by applying it to the set of vulnerabilities found on two live websites.Comment: Accepted at 5th International Conference on Networking, Systems and Security (5th NSysS 2018

A new 3D printed radial flow-cell for chemiluminescence detection: Application in ion chromatographic determination of hydrogen peroxide in urine and coffee extracts

A new polymer flow-cell for chemiluminescence detection (CLD) has been designed and developed by diverging multiple linear channels from a common centre port in a radial arrangement. The fabrication of radial flow-cell by 3D PolyJet printing and fused deposition modeling (FDM) has been evaluated, and compared with a similarly prepared spiral flow-cell design commonly used in chemiluminescence detectors. The radial flow-cell required only 10 h of post-PolyJet print processing time as compared to ca. 360 h long post-PolyJet print processing time required for the spiral flow-cell. Using flow injection analysis, the PolyJet 3D printed radial flow-cell provided an increase in both the signal magnitude and duration, with an average increase in the peak height of 63% and 58%, peak area of 89% and 90%, and peak base width of 41% and 42%, as compared to a coiled-tubing spiral flow-cell and the PolyJet 3D printed spiral flow-cell, respectively. Computational fluid dynamic (CFD) simulations were applied to understand the origin of the higher CLD signal obtained with the radial flow-cell design, indicating higher spatial coverage near the inlet and lower linear velocities in the radial flow-cell. The developed PolyJet 3D printed radial flow-cell was applied in a new ion chromatography chemiluminescence based assay for the detection of H2O2 in urine and coffee extracts

Role of vacuum assisted closure therapy in chronic wounds: for some cases in Navi Mumbai

Background: This study was performed to evaluate the results of vacuum assisted wound therapy in patients with chronic non healing ulcer.Methods: The study was conducted in the department of General Surgery at a tertiary care hospital. It was an observational study with prospective design. The role of NPWT in various wounds was studied in 10 patients.Results: Out of 10 wounds taken in the study, 7 wounds  reduced  in  area  & were  resurfaced with Split thickness skin  grafting and 3 wounds  showed  reduction in area & were subjected to secondary closure.Conclusions: Vacuum assisted closure (VAC) therapy provides sterile and controlled environment to large, exudating wound  surfaces and is  treatment  of  choice  in  infected / non – healing wounds,  not  responding  to  standard  treatment

Electrochemical characterisation of nanoparticulate zirconium dioxide-on-gold electrode for electrochemical detection in flow-based analytical systems

The modification of gold (Au) electrode using zirconium dioxide nanoparticles (ZrO2 NPs) has been investigated for enhanced electrochemical (EC) detection in flow-based analytical systems. The average size of ZrO2 NPs deposited in a facile procedure on the Au electrode surface was calculated as 22.5 ± 7 nm. Redox behaviour of a test solute, ferrocyanide [Fe(CN)6]4-, on the bare- and ZrO2-Au electrodes was initially investigated using cyclic voltammetry. From the voltammograms of bare- and ZrO2-Au electrodes, the EC reversibility values and effective surface area were experimentally determined for the first-time in this study. Further, EC reversibility and 100% increase in effective electrode surface area were confirmed in ZrO2-Au electrode through investigating the detection response (current). The EC performance of the ZrO2-Au electrode was then investigated in amperometric detection of selected electroactive solutes separated by reversed-phase HPLC. The limits of detection (LODs), based upon an injection volume of 10 μL for ascorbic acid, 2,3-dihydroxybenzoic acid and pyrocatechol were 0.09 μM, 0.04 μM, and 0.10 μM, respectively (RSD 2.5%, n = 9, r2 = 0.99 for concentration range 1-100 μM). These LODs for the ZrO2-Au electrode were 2-times lower for 2,3-DHBA, and pyrocatechol than the lowest LODs reported in the literature for EC detection in HPLC. The ZrO2-Au electrode demonstrated satisfactory repeatability of preparation, detection reproducibility and high stability (8.5 h) during continuous-flow in FIA and 45 days during intermittent use with HPLC, at flow rate of 0.6 mL min-1. This work has demonstrated a comprehensive EC characterisation of Au electrode with nanoparticulate ZrO2 for flow-based analytical systems

Lower bounds on the dilation of plane spanners

(I) We exhibit a set of 23 points in the plane that has dilation at least $1.4308$, improving the previously best lower bound of $1.4161$ for the worst-case dilation of plane spanners. (II) For every integer $n\geq13$, there exists an $n$-element point set $S$ such that the degree 3 dilation of $S$ denoted by $\delta_0(S,3) \text{ equals } 1+\sqrt{3}=2.7321\ldots$ in the domain of plane geometric spanners. In the same domain, we show that for every integer $n\geq6$, there exists a an $n$-element point set $S$ such that the degree 4 dilation of $S$ denoted by $\delta_0(S,4) \text{ equals } 1 + \sqrt{(5-\sqrt{5})/2}=2.1755\ldots$ The previous best lower bound of $1.4161$ holds for any degree. (III) For every integer $n\geq6$, there exists an $n$-element point set $S$ such that the stretch factor of the greedy triangulation of $S$ is at least $2.0268$.Comment: Revised definitions in the introduction; 23 pages, 15 figures; 2 table

The effects of yogurt supplementation and nutritional education on malnourished infants : a pilot RCT in Dhaka's slums

Our objective was to quantify the effects of yogurt supplementation and nutrition education over three months on the linear growth of infants at risk of stunting. We conducted a three-arm pilot randomized controlled trial: (1) nutrition education for mothers; (2) nutrition education plus a daily yogurt supplement (50 g) for the index child; and (3) usual care (control). Dyads of children aged 4–6 months and at risk of stunting [length-for-age z-score (LAZ) ≤ −1 SD and >−2 SD] and their mothers with ≤10 years of education were eligible for the study. Participants were recruited from five slum areas in Dhaka, Bangladesh. Intention-to-treat (N = 162) and complete-case analyses (N = 127) showed no between-group statistically significant differences in LAZ or weight-for-age (WAZ). However, the yogurt group showed greater change in linear growth compared to the control (LAZ: mean difference 0.20, 95% CI: −0.06, 0.47, p-value 0.13), which was also slightly greater than the education-only group. Children in the yogurt plus group were five times (95% CI: 0.80, 31.80, p-value 0.09) more likely to meet the minimum dietary diversity (MDD) score compared to the control. A 3-month follow-up of this pilot study did not demonstrate that yogurt was beneficial to linear growth. However, there were encouraging trends that merit replication of the intervention with larger samples and longer follow-ups