998 research outputs found
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
Lower bounds on the dilation of plane spanners
(I) We exhibit a set of 23 points in the plane that has dilation at least
, improving the previously best lower bound of for the
worst-case dilation of plane spanners.
(II) For every integer , there exists an -element point set
such that the degree 3 dilation of denoted by in the domain of plane geometric spanners. In the
same domain, we show that for every integer , there exists a an
-element point set such that the degree 4 dilation of denoted by
The
previous best lower bound of holds for any degree.
(III) For every integer , there exists an -element point set
such that the stretch factor of the greedy triangulation of is at least
.Comment: Revised definitions in the introduction; 23 pages, 15 figures; 2
table
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Dairy consumption and cardiometabolic diseases: systematic review and updated meta-analyses of prospective cohort studies
Purpose of Review Dairy products contain both beneficial and harmful nutrients in relation to cardiometabolic diseases. Here, we
provide the latest scientific evidence regarding the relationship between dairy products and cardiometabolic diseases by
reviewing the literature and updating meta-analyses of observational studies.
Recent Findings We updated our previous meta-analyses of cohort studies on type 2 diabetes, coronary heart disease (CHD), and
stroke with nine studies and confirmed previous results. Total dairy and low-fat dairy (per 200 g/d) were inversely associated with
a 3–4% lower risk of diabetes. Yogurt was non-linearly inversely associatedwith diabetes (RR = 0.86, 95%CI: 0.83–0.90 at 80 g/
d). Total dairy and milk were not associated with CHD (RR~1.0). An increment of 200 g of daily milk intake was associated with
an 8% lower risk of stroke.
Summary The latest scientific evidence confirmed neutral or beneficial associations between dairy products and risk of cardiometabolic
diseases
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
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Attitude of NRLM Beneficiaries towards Livelihood Diversification in Baghelkhand Region of Madhya Pradesh, India
In the rural areas, people diversify because of geographical isolation, low quality physical infrastructure, under developing markets, resources scarcity, incidence of some natural disaster and agricultural failure etc. Considering the above statement, find researchable issues were recognize as What are the attitude of NRLM beneficiaries towards livelihood diversification? Livelihood diversification is one of the dynamic solutions that are now occurring in rural regions and acting as a catalyst for economic growth and development. To cope with changing situation, mitigate losses from crop failure, economic and environmental risk rural households are adopting various on-farm and off-farm strategies as drought-tolerant crops and mixed farming, vegetable and fruit production, animal husbandry, eggs and poultry, trade, formally employee, mining, manufacturing, construction, transport, carpentry, petty trade etc. The study was done during 2022-23 in Rewa and Shahdol districts under Baghelkhand region of Madhya Pradesh due to highest number of beneficiaries registered in respective districts under NRLM at state level. In this study Ex-post facto research design, and 3 percent proportionate random sampling technique under multi-stage procedures were adopted. Thus 221 respondents were selected which were personally interviewed by using interview schedule, to analyze the attitude of NRLM beneficiaries towards livelihood diversification. The results of the study revealed that 50.22 percent respondent had medium level of attitude towards livelihood diversification
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Profile of National Rural Livelihood Mission (NRLM) beneficiaries in Madhya Pradesh
The National Rural Livelihoods Mission (NRLM) is a poverty alleviation programme implemented by The Ministry of Rural Development, GOI. The programme aims to promote self-employment and the organization of rural poor. The study was done during 2022-23 in Rewa and Shahdol districts in Baghelkhand region of Madhya Pradesh based on highest number of beneficiaries registered in selected districts under NRLM in the state of Madhya Pradesh. In this study Ex-post facto research design, and proportionate random sampling technique was adopted at 3 percent under multi-stage sampling procedures. Thus 221 respondents were selected which were personally interviewed to known the profile of beneficiaries. The results revealed that 65.60 percent of beneficiaries belong to young age, 24.00 percent have high school level of education, 47.07 percent have medium size of family, 55.20 percent have low level of farming experience, 50.20 percent have medium level of income, 53.86 percent have medium level credit accessible, 47.52 percent have marginal land holding, 38.00 percent had low level of information seeking behaviour, 41.17 percent have high level of mass media exposures, 39.82 percent have medium level of risk preference, 43.43 percent have medium level of awareness towards diversification, 51.58 percent have medium level of economic motivation, 46.15 percent have medium level of innovative, 41.65 percent have medium decision-making ability and 39.80 percent of beneficiaries have low level of management efficiency
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
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