Genotype by Environment Interaction (G x E) and Grain Yield Stability Analysis of Ethiopian Linseed and Niger Seed Varieties

General Background: Niger seed [(Guizotia abyssinica (L.F.) Cass.), 2n = 30] and Linseed [(Linum usitatissimum L.), n=15] are indigenous oil crops of Ethiopia. Over many years, there are a few Linseed and Niger seed varieties developed and released through intensive breeding and genetics research program in Ethiopia. However, whether these varieties are stable, adaptable to the environments of Western Ethiopia and similar agro-ecologies are not clear.Objectives: The objectives of the study were to (i) assess genotype by environment interaction (G x E) and (ii) identify stable and adaptable Linseed and Niger seed varieties for specific and wide adaptions.Materials and methods: All Niger seed and Linseed released varieties of Ethiopia between the years 1984 and 2008 were tested for multi-locations and years. Independent experiments of linseed and Niger seed varieties were evaluated in Randomized Complete Block Design replicated three times. Eight varieties of Linseed with one local variety were evaluated at Arjo, Gute and Shambu locations. In addition, five Niger seed varieties including one local variety were tested at Bako, Gute and Shambu locations.Summary of the result and application of the findings: The seed yields ranged between 0.898 tons ha-1 and 1.575 tons/ha for Linseed and between 0.600 tons ha-1 and 0.690 tons ha-1 for Niger seed. Analysis of variance using additive main effects and multiplicative interactions (AMMI) model revealed significant differences (pG0.01) for genotype, environment, genotype x environment interaction and interaction principal component (IPCA1) for Linseed, while only environment was found to be significantly different for Niger seed. Based on AMMI analysis, Kulumsa-1 was the best yielding, stable and widely adapted, while CI-1525 and Berene were high yielding but unstable and specifically adapted Linseed varieties to high yielding environments. Belay 96, Chilalo, Tole and CI-1652 were moderately stable and adapted to high yielding environments. Among Niger seed varieties, Shambu-1 and Esete-1 had comparable seed yield with moderately stable for the tested environments whereas Kuyu and local variety were unstable and not adopted to the testing environments.Key words/phrases: Adapted variety, Additive main effect and multiplicative interaction (AMMI), Genotype x environment (G x E) interaction, Stable variet

Comparison of ophthalmic training in 6 English-speaking countries

OBJECTIVE: To compare key characteristics of ophthalmology training programs in 6 different English-speaking countries: Australia, New Zealand, Canada, Ireland, the United Kingdom, and the United States. PARTICIPANTS: Seven ophthalmologists with personal knowledge of all 6 systems contributed. METHODS: The main features examined were career pathway, duration of training, surgical training, governing bodies, and examination structure. Data were collected from the literature, online resources, and personal experience. RESULTS: Several differences were highlighted, including length of training (ranging from 4 to 9 years after medical school), number of surgical procedures such as cataracts (ranging from minimum 86 to approximately 600), and structure of fellowship training. CONCLUSIONS: As trainees increasingly seek international experience to enhance their knowledge and skills, the similarities and differences between training programs in different countries have become more relevant. Some of these differences may reflect differing needs of different patient populations and different healthcare delivery systems across the globe. However, these differences should also prompt educators to more carefully scrutinize their own training system and search for potential improvements

Label-Free Density Measurements of Radial Peripapillary Capillaries in the Human Retina

Radial peripapillary capillaries (RPCs) comprise a unique network of capillary beds within the retinal nerve fibre layer (RNFL) and play a critical role in satisfying the nutritional requirements of retinal ganglion cell (RGC) axons. Understanding the topographical and morphological characteristics of these networks through in vivo techniques may improve our understanding about the role of RPCs in RGC axonal health and disease. This study utilizes a novel, non-invasive and label-free optical imaging technique, speckle variance optical coherence tomography (svOCT), for quantitatively studying RPC networks in the human retina. Six different retinal eccentricities from 16 healthy eyes were imaged using svOCT. The same eccentricities were histologically imaged in 9 healthy donor eyes with a confocal scanning laser microscope. Donor eyes were subject to perfusion-based labeling techniques prior to retinal dissection, flat mounting and visualization with the microscope. Capillary density and diameter measurements from each eccentricity in svOCT and histological images were compared. Data from svOCT images were also analysed to determine if there was a correlation between RNFL thickness and RPC density. The results are as follows: (1) The morphological characteristics of RPC networks on svOCT images are comparable to histological images; (2) With the exception of the nasal peripapillary region, there were no significant differences in RPC density measurements between svOCT and histological images; (3) Capillary diameter measurements were significantly greater in svOCT images compared to histology; (4) There is a positive correlation between RPC density and RNFL thickness. The findings in this study suggest that svOCT is a reliable modality for analyzing RPC networks in the human retina. It may therefore be a valuable tool for aiding our understanding about vasculogenic mechanisms that are involved in RGC axonopathies. Further work is required to explore the reason for some of the quantitative differences between svOCT and histology

A novel absorptive/reflective solar concentrator for heat and electricity generation: an optical and thermal analysis.

The crossed compound parabolic concentrator (CCPC) is one of the most efficient non-imaging solar concentrators used as a stationary solar concentrator or as a second stage solar concentrator. In this study, the CCPC is modified to demonstrate for the first time a new generation of solar concentrators working simultaneously as an electricity generator and thermal collector. The CCPC is designed to have two complementary surfaces, one reflective and one absorptive, and is named as an absorptive/reflective CCPC (AR-CCPC). Usually, the height of the CCPC is truncated with a minor sacrifice of the geometric concentration. These truncated surfaces rather than being eliminated are instead replaced with absorbent surfaces to collect heat from solar radiation. The optical efficiency including absorptive/reflective part of the AR-CCPC was simulated and compared for different geometric concentration ratios varying from 3.6× to 4×. It was found that the combined optical efficiency of the AR-CCPC 3.6×/4× remained constant and high all day long and that it had the highest total optical efficiency compared to other concentrators. In addition, the temperature distributions of AR-CCPC surfaces and the assembled solar cell were simulated based on those heat flux boundary conditions. It was shown that the addition of a thermal absorbent surface can increase the wall temperature. The maximum value reached 321.5 K at the front wall under 50° incidence. The experimental verification was also adopted to show the benefits of using absorbent surfaces. The initial results are very promising and significant for the enhancement of solar concentrator systems with lower concentrations

Influence of Nano-/Microfiller Addition on Mechanical and Morphological Performance of Kenaf/Glass Fibre-Reinforced Hybrid Composites

Natural-based composite’s progress as carriers has revealed many benefits in biomedicine, notably in the construction field, synthetic biology, and genetic engineering. Compared to analogous composites without nanoparticles, incorporating nanoparticles into polymeric materials improved architectural performance, physiological connections, and ecological features. The major goal of the current investigation is to determine the impact of nano-/micro-TiO2 on the mechanical characteristics of kenaf/glass/epoxy hybrids. The samples have been created using a hand layup method and a variety of filler loading and stacking sequences. The addition of nano-/microfiller significantly improved the mechanical performance of the epoxy/hybrid composite material. It was discovered that nanofiller-added composite materials fared better when composites were compared to and without microfilter-added composites. SEM was used to investigate the microstructure of the interfaces to ensure a good understanding of interfacial adherence between the reinforcement and their matrix. Compared to pure epoxy resin, the 15 wt% of microfiller additions of glass-kenaf-kenaf-glass type composites exhibit a 39.48% improvement in tensile and a 42.88% improvement in flexural. Similarly, 5 wt% nanofiller addition reveals a 44.214% improvement in tensile and a 50.50% improvement in flexural

In situ, broadband measurement of the radio frequency attenuation length at Summit Station, Greenland

Over the last 25 years, radiowave detection of neutrino-generated signals, using cold polar ice as the neutrino target, has emerged as perhaps the most promising technique for detection of extragalactic ultra-high energy neutrinos (corresponding to neutrino energies in excess of 0.01 Joules, or $10^{17}$ electron volts). During the summer of 2021 and in tandem with the initial deployment of the Radio Neutrino Observatory in Greenland (RNO-G), we conducted radioglaciological measurements at Summit Station, Greenland to refine our understanding of the ice target. We report the result of one such measurement, the radio-frequency electric field attenuation length $L_\alpha$. We find an approximately linear dependence of $L_\alpha$ on frequency with the best fit of the average field attenuation for the upper 1500 m of ice: $\langle L_\alpha \rangle = \big( (1154 \pm 121) - (0.81 \pm 0.14) (\nu/$MHz$)\big)$ m for frequencies $\nu \in [145 - 350]$ MHz.Comment: 13 pages, 8 figures, Accepted to Journal of Glaciolog

Precision measurement of the index of refraction of deep glacial ice at radio frequencies at Summit Station, Greenland

Glacial ice is used as a target material for the detection of ultra-high energy neutrinos, by measuring the radio signals that are emitted when those neutrinos interact in the ice. Thanks to the large attenuation length at radio frequencies, these signals can be detected over distances of several kilometers. One experiment taking advantage of this is the Radio Neutrino Observatory Greenland (RNO-G), currently under construction at Summit Station, near the apex of the Greenland ice sheet. These experiments require a thorough understanding of the dielectric properties of ice at radio frequencies. Towards this goal, calibration campaigns have been undertaken at Summit, during which we recorded radio reflections off internal layers in the ice sheet. Using data from the nearby GISP2 and GRIP ice cores, we show that these reflectors can be associated with features in the ice conductivity profiles; we use this connection to determine the index of refraction of the bulk ice as n=1.778 +/- 0.006

Search for low-mass dark matter via bremsstrahlung radiation and the Migdal effect in SuperCDMS

We present a new analysis of previously published SuperCDMS data using a profile likelihood framework to search for sub-GeV dark matter (DM) particles through two inelastic scattering channels: bremsstrahlung radiation and the Migdal effect. By considering these possible inelastic scattering channels, experimental sensitivity can be extended to DM masses that are undetectable through the DM-nucleon elastic scattering channel, given the energy threshold of current experiments. We exclude DM masses down to 220  MeV/c2 at 2.7×10−30  cm2 via the bremsstrahlung channel. The Migdal channel search provides overall considerably more stringent limits and excludes DM masses down to 30  MeV/c2 at 5.0×10−30  cm2

Pesticide Risk Reduction Programme : Feasibility Study of the Proposed Pesticide Registration and Post-Registration Processes

Report on developing guidelines and procedures for the pesticide registration in Ethiopia in a scientifically underpinned way and as specific as possible for Ethiopian conditions. It covers the aspects of efficacy assessment, human health risk assessment as well as environmental risk assessment. It aims to develop the capacity at the APHRD to apply these guidelines and procedures. The Work package will result in an evaluation manual plus software tool for the Animal and Plant Health Regulatory Directorate (APHRD) of the Ministry of Agriculture of Ethiopia. The user-friendly software tool operationalises the guidelines and procedures for human health risk assessment and environmental risk assessment; all basic pesticide data can be entered in it and these will be used for the risk estimates