Rain event properties at the source of the Blue Nile River

In the present study, spatial and temporal patterns of rain event properties are analysed. These event properties are rain event depth, event duration, mean event rain rate, peak rain rate and the time span between two consecutive rain events which is referred to as inter-event time (IET). In addition, we assessed how rain event properties change when the period over which rainfall data is aggregated changes from 1 to 6 min and when the minimum inter-event time (MIT) changes from 30 min to 8 h. Rainfall data is obtained from a field campaign in two wet seasons of June–August (JJA) of 2007 and 2008 in Gilgel Abbay watershed that is situated at the source basin of the Upper Blue Nile River in Ethiopia. The rainfall data was automatically recorded at eight stations. The results revealed that rain event depth is more related to peak rain rate than to event duration. At the start and towards the end of the wet season, the rain events have larger depth with longer duration and longer IET than those in mid-season. Event rain rate and IET are strongly related to terrain elevation. Sekela which is on a mountain area has the shortest IET while Bahir Dar which is at the south shore of Lake Tana has the longest IET. The period over which rainfall data is aggregated significantly affected the values of rain event properties that are estimated using relatively small value (30 min) of MIT but its effect diminished when the MIT is increased to 8 h. It is shown that increasing the value of MIT has the largest effect on rain event properties of mountain stations that are characterised by high rainfall intermittency

The Queue-Number of Posets of Bounded Width or Height

Heath and Pemmaraju conjectured that the queue-number of a poset is bounded by its width and if the poset is planar then also by its height. We show that there are planar posets whose queue-number is larger than their height, refuting the second conjecture. On the other hand, we show that any poset of width $2$ has queue-number at most $2$, thus confirming the first conjecture in the first non-trivial case. Moreover, we improve the previously best known bounds and show that planar posets of width $w$ have queue-number at most $3w-2$ while any planar poset with $0$ and $1$ has queue-number at most its width.Comment: 14 pages, 10 figures, Appears in the Proceedings of the 26th International Symposium on Graph Drawing and Network Visualization (GD 2018

Studies on the Occurrence and Population Distribution of Nematodes with yam (Dioscorea rotundata Poir) tubers in Benue State, Nigeria

Yam (Dioscorea spp) nematodes have been variously reported to reduce tuber yield and quality worldwide. In the present study, a survey was done to estimate types, frequency and population density of nematodes associated with yam tubers at each of the Local Government haedquarters and two villages in Benue state of Nigeria. A total of 250 yam tubers were sampled randomly in the survey markets between April and May, 2017. Each yam sample was processed by peeling the periderm (one inch thick) out of which a 10 g sub-sample tuber was separately put in a blender with some quantity of water and mercerated at low speed for 15 seconds. Plant-parasitic nematodes were recovered from the yam tubers using a modified extraction tray method. Five nematode species were found in association with yam tubers as follows: Scutellonema bradys, Meloidogyne spp, Pratylenchus spp, Rotylenchulus spp and Tylenchus spp. Scutellonema bradys was the most ubiquitous, occuring at a 100% frequency rating in all the samples while Meloidogyne spp, Pratylenchus spp, Rotylenchulus spp and Tylenchus spp. were 29.60%, 16.80%, 8.80% and 4.80% respectively. Though the study revealed that Rotylenchulus spp and Tylenchus spp. were poor parasites of yam tubers, yet there was a widespread distribution of Scutellonema bradys, Meloidogyne spp and Pratylenchus spp on yam tubers in Benue State of Nigeria, thus control of plant-parasitic nematodes is encouraged for improved tuber quality

Stochastic approach to inflation II: classicality, coarse-graining and noises

In this work we generalize a previously developed semiclassical approach to inflation, devoted to the analysis of the effective dynamics of coarse-grained fields, which are essential to the stochastic approach to inflation. We consider general non-trivial momentum distributions when defining these fields. The use of smooth cutoffs in momentum space avoids highly singular quantum noise correlations and allows us to consider the whole quantum noise sector when analyzing the conditions for the validity of an effective classical dynamical description of the coarse-grained field. We show that the weighting of modes has physical consequences, and thus cannot be considered as a mere mathematical artifact. In particular we discuss the exponential inflationary scenario and show that colored noises appear with cutoff dependent amplitudes.Comment: 18 pages, revtex, no figure

Practices and performance outcomes of green supply chain management initiatives in the garment industry

Purpose The garments/textiles industry is the second most polluting industry in the world. However, efforts to understand and curtail its adverse environmental impacts have not been commensurate, and previous works have largely been fragmented and disjointed. This study aims to conduct a comprehensive and systematic green supply chain management (GSCM) investigation on this industry, where a multidimensional framework involving green supply chain practices and performance is developed, validated and applied. Design/methodology/approach A framework consisting of 12 constructs (8 on practices and 4 on performance) and their underlying measures were developed through an extensive literature review. A survey methodology was used to obtain responses from 403 garment-manufacturing firms in Bangladesh, one of the leading garment producers in the world. Confirmatory factor analysis and structural equation modelling were used first to validate the first- and second-order constructs and then test the hypothesized relationships. Findings Internal environmental management and cooperation with stakeholders were identified as necessary precursors for implementing the second-order green supply chain practices comprising green design, green purchasing, green manufacturing, green transportation, green facilities and end-of-life management. The implementation of green supply chain practices was found to have a (direct) positive impact on environmental, economic and operational performance and an indirect positive impact on organizational performance. Similarly, both economic and operational performance was found to impact organizational performance positively. Surprisingly, a negative relationship (albeit low) was observed between environmental and organizational performance. Also, garment-manufacturing firms were found to have been unable to translate their IEM capabilities into strategic and long-term cooperation with stakeholders. Research limitations/implications The study fills a gap in the literature about applying/implementing GSCM in the garment industry. Future studies in the garment industry and elsewhere could utilize the framework to understand further the synergistic impact of green supply chain practices on performance. Practical implications The findings provide practitioners, policymakers and organizations associated with the garment industry with critical insights on the various opportunities and challenges in adopting GSCM. Also, the positive impact of green supply chain practices on performance could provide the impetus for manufacturing firms to adopt GSCM. Originality/value A comprehensive GSCM investigation on the garment industry has not been previously attempted and constitutes the novelty of this work. Also, Bangladesh is the second-largest garment exporter worldwide, making this study contribution even more valuable

Fabrication of integrated planar gunn diode and micro-cooler on GaAs substrate

We demonstrate fabrication of an integrated micro cooler with the planar Gunn diode and characterise its performance. First experimental results have shown a small cooling at the surface of the micro cooler. This is first demonstration of an integrated micro-cooler with a planar Gunn diode

Comment on "Gravitationally Induced Neutrino-Oscillation Phases"

We critically examine the recent claim (gr-qc/9603008) of a ``new effect'' of gravitationally induced quantum mechanical phases in neutrino oscillations. A straightforward exercise in the Schwarzschild coordinates appropriate to a spherically symmetric non-rotating star shows that, although there is a general relativistic effect of the star's gravity on neutrino oscillations, it is not of the form claimed, and is too small to be measured.Comment: Plain LaTeX, 7 pages, no figure