Meiotic behaviour of Eragrostis tef and,i> Eragrostis Pilosa

Tef (Eragrostis tef (Zucc.) Trotter) is major cereal crop cultivated in Ethiopia. It occupies approximately two million hectares of land each year. However, little has been done on meiotic chromosome study of the interspes hybrid. So, studies were conducted to examine meiotic behavior and pollen fertility of the F1-hybrid (E. tef x E. pilosa) and parental lines at Addis Ababa, Ethiopia in 200 7/08. The F1-hybrid plant showed regular meiotic cell division and high level of pollen fertility (94.3%). It also produced better seed and biomass yield and number of tillers than the parental lines which are the manifestation of meiotic stability in the hybrid and the subsequent generations. Pollen fertility test of the parental lines and selected recombinant inbred lines of E. tef and E. pilosa cross was also high (90 - 95%), which are an indication of regular meiotic chromosome division. The resultdemonstrated chromosome stability of the hybrid plant, which is important for widening the genetic pool of tef germplasm through conventional crossing with E. pilosa. The study further strengthen the view that the two species are very closely related

The OmegaWhite Survey for Short-Period Variable Stars IV: Discovery of the warm DQ white dwarf OW J175358.85-310728.9

We present the discovery and follow-up observations of the second known variable warm DQ white dwarf OW J175358.85-310728.9 (OW J1753-3107). OW J1753-3107 is the brightest of any of the currently known warm or hot DQ and was discovered in the OmegaWhite Survey as exhibiting optical variations on a period of 35.5452 (2) mins, with no evidence for other periods in its light curves. This period has remained constant over the last two years and a single-period sinusoidal model provides a good fit for all follow-up light curves. The spectrum consists of a very blue continuum with strong absorption lines of neutral and ionised carbon, a broad He I 4471 A line, and possibly weaker hydrogen lines. The C I lines are Zeeman split, and indicate the presence of a strong magnetic field. Using spectral Paschen-Back model descriptions, we determine that OW J1753-3107 exhibits the following physical parameters: T_eff = 15430 K, log(g) = 9.0, log(N(C)/N(He)) = -1.2, and the mean magnetic field strength is B_z =2.1 MG. This relatively low temperature and carbon abundance (compared to the expected properties of hot DQs) is similar to that seen in the other warm DQ SDSS J1036+6522. Although OW J1753-3107 appears to be a twin of SDSS J1036+6522, it exhibits a modulation on a period slightly longer than the dominant period in SDSS J1036+6522 and has a higher carbon abundance. The source of variations is uncertain, but they are believed to originate from the rotation of the magnetic white dwarf.Comment: 11 pages, 8 figures, 7 tables. Accepted for publication by MNRA

Integrating phenotypic evaluations with a molecular diversity assessment of an Ethiopian collection of common bean landraces

Understanding the organisation of genetic diversity in a crop species is a key element for both the conservation and utilisation of its genetic resources. In the case of common bean ( Phaseolus vulgaris L.), Ethiopia is one of the secondary centers of diversity of this species. Hence, this study sought to improve our understanding of genetic diversity of common bean by integrating morphological and agronomic evaluations with prior molecular diversity data from a collection of landrace accessions from different common bean growing regions of Ethiopia. The samples studied included 115 landraces, four standard varieties, and two control genotypes. Twenty agronomic traits and morphological descriptors were used to evaluate the accessions under field conditions. A Principal Component Analysis clearly separated the accessions into the Andean and Mesoamerican gene pools, with the first two axes explaining most of the variation. Step-wise discriminant and canonical correlation analyses, with all variables or only the morphological variables, enabled the identification of characters distinguishing accessions from the Andean/Mesoamerican gene pools, and their respective ecogeographic races. Data distinguishing racial and morphological traits were used to clarify the identities of five cluster groups, identified at STRUCTURE preset K = 5, in a preceding study. The three Andean cluster groups were shown to belong to two of the races in the gene pool, \u2018Nueva Granada\u2019 and \u2018Peru\u2019; while the two Mesoamerican groups were from the race \u2018Mesoamerica\u2019. By integrating the morphological and agronomic evaluation of an Ethiopian germplasm collection of common bean, initially performed just based on molecular characterisation, we were able to improve our understanding of the organisation of this diversity. Our results suggest extensive hybridisation between the Andean and Mesoamerican gene pools after introduction of common bean germplasm in Ethiopia.Connaitre l\u2019organisation de la diversit\ue9 g\ue9n\ue9tique sur une culture est un \ue9l\ue9ment important \ue0 la fois pour la conservation et l\u2019utilisation de ses ressources g\ue9n\ue9tiques. Dans le cas du haricot commun ( Phaseolus vulgaris L), l\u2019Ethiopie est l\u2019un des centres secondaires de la diversit\ue9 de l\u2019esp\ue8ce. Par cons\ue9quent, cette \ue9tude cherche \ue0 am\ue9liorer notre compr\ue9hension de la diversit\ue9 g\ue9n\ue9tique du haricot commun en int\ue9grant les \ue9valuations morphologique et agronomiques avec une \ue9valuation pr\ue9alable de la diversit\ue9 mol\ue9culaire d\u2019une collection de cultivars traditionnels venus de diff\ue9rentes r\ue9gions productrices du haricot commun de l\u2019Ethiopie. Les \ue9chantillons utilis\ue9s comprennent 115 cultivars traditionnels, quatre vari\ue9t\ue9s standards, et deux g\ue9notypes contr\uf4les. Vingt traits descripteurs agronomiques et morphologiques \ue9taientutilis\ue9s pour \ue9valuer les accessions dans des conditions de champ. Une analyse en composante principale a clairement s\ue9par\ue9 les accessions en des pools de g\ue8nes Andins et M\ue9soam\ue9ricains avec les deux premiers axes expliquant la plus grande variation. Les analyses discriminante par \ue9tapes la corr\ue9lation canonique, avec toutes les variables ou seule avec les variables morphologiques, ont permis l\u2019identification des caract\ue8res discriminant les accessions des pools de g\ue8nes Andins et M\ue9soam\ue9ricains, et leurs races Eco g\ue9ographiques respectives. Les donn\ue9es discriminant les traits raciaux et morphologiques \ue9taient utilis\ue9s pour clarifier les identit\ue9s des cinq classes, identifi\ue9es \ue0 la configuration pr\ue9finie K= 5, dans l\u2019\ue9tude pr\ue9c\ue9dente. Les trois groupes de classes Andines appartiennent \ue0 deux races dans le pool de g\ue8nes, \u2018Nueva Granada\u2019 et \u2018Peru\u2019\ua0; alors que les groupes M\ue9soam\ue9ricains \ue9taient de la race \u2018M\ue9soam\ue9rica\u2019. En int\ue9grant l\u2019\ue9valuation morphologique et agronomique de la collection du germoplasm du haricot commun Ethiopien, initialement conduit juste sur la base de la caract\ue9risation mol\ue9culaire, nous avions pu am\ue9liorer notrecompr\ue9hension de l\u2019organisation de cette diversit\ue9. Nos r\ue9sultats sugg\ue8rent une hybridation extensive entre les pools de g\ue8nes Andins et M\ue9soam\ue9ricains apr\ue8s une introduction du germoplasm du haricot commun de l\u2019Ethiopie

Phytochemical investigations of three Rhodocodon (Hyacinthaceae Sensu APG II) species

The genus Rhodocodon (Hyacinthaceae sensu APG II) is endemic to Madagascar and its phytochemistry has not been described previously. The phytochemistry of three species in this genus has been investigated and eight compounds, including three bufadienolides (compounds 1, 4, and 5), a norlignan (2), and four homoisoflavonoids (compounds 3 and 6-8) have been isolated and identified. Compounds 1-3 and 6-8 have not been described previously. The COX-2 inhibitory activity of compound 6 and compound 7 acetate (compound 7A) were investigated on isolated colorectal cancer cells. Compounds 6 and 7A inhibited COX-2 by 10% and 8%, respectively, at a concentration of 12.5 M compared to 12% for 1 mM aspirin (the positive control)

Global, regional, and national burden of diabetes from 1990 to 2021, with projections of prevalence to 2050:a systematic analysis for the Global Burden of Disease Study 2021

Background: Diabetes is one of the leading causes of death and disability worldwide, and affects people regardless of country, age group, or sex. Using the most recent evidentiary and analytical framework from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD), we produced location-specific, age-specific, and sex-specific estimates of diabetes prevalence and burden from 1990 to 2021, the proportion of type 1 and type 2 diabetes in 2021, the proportion of the type 2 diabetes burden attributable to selected risk factors, and projections of diabetes prevalence through 2050. Methods: Estimates of diabetes prevalence and burden were computed in 204 countries and territories, across 25 age groups, for males and females separately and combined; these estimates comprised lost years of healthy life, measured in disability-adjusted life-years (DALYs; defined as the sum of years of life lost [YLLs] and years lived with disability [YLDs]). We used the Cause of Death Ensemble model (CODEm) approach to estimate deaths due to diabetes, incorporating 25 666 location-years of data from vital registration and verbal autopsy reports in separate total (including both type 1 and type 2 diabetes) and type-specific models. Other forms of diabetes, including gestational and monogenic diabetes, were not explicitly modelled. Total and type 1 diabetes prevalence was estimated by use of a Bayesian meta-regression modelling tool, DisMod-MR 2.1, to analyse 1527 location-years of data from the scientific literature, survey microdata, and insurance claims; type 2 diabetes estimates were computed by subtracting type 1 diabetes from total estimates. Mortality and prevalence estimates, along with standard life expectancy and disability weights, were used to calculate YLLs, YLDs, and DALYs. When appropriate, we extrapolated estimates to a hypothetical population with a standardised age structure to allow comparison in populations with different age structures. We used the comparative risk assessment framework to estimate the risk-attributable type 2 diabetes burden for 16 risk factors falling under risk categories including environmental and occupational factors, tobacco use, high alcohol use, high body-mass index (BMI), dietary factors, and low physical activity. Using a regression framework, we forecast type 1 and type 2 diabetes prevalence through 2050 with Socio-demographic Index (SDI) and high BMI as predictors, respectively. Findings: In 2021, there were 529 million (95% uncertainty interval [UI] 500–564) people living with diabetes worldwide, and the global age-standardised total diabetes prevalence was 6·1% (5·8–6·5). At the super-region level, the highest age-standardised rates were observed in north Africa and the Middle East (9·3% [8·7–9·9]) and, at the regional level, in Oceania (12·3% [11·5–13·0]). Nationally, Qatar had the world's highest age-specific prevalence of diabetes, at 76·1% (73·1–79·5) in individuals aged 75–79 years. Total diabetes prevalence—especially among older adults—primarily reflects type 2 diabetes, which in 2021 accounted for 96·0% (95·1–96·8) of diabetes cases and 95·4% (94·9–95·9) of diabetes DALYs worldwide. In 2021, 52·2% (25·5–71·8) of global type 2 diabetes DALYs were attributable to high BMI. The contribution of high BMI to type 2 diabetes DALYs rose by 24·3% (18·5–30·4) worldwide between 1990 and 2021. By 2050, more than 1·31 billion (1·22–1·39) people are projected to have diabetes, with expected age-standardised total diabetes prevalence rates greater than 10% in two super-regions: 16·8% (16·1–17·6) in north Africa and the Middle East and 11·3% (10·8–11·9) in Latin America and Caribbean. By 2050, 89 (43·6%) of 204 countries and territories will have an age-standardised rate greater than 10%. Interpretation: Diabetes remains a substantial public health issue. Type 2 diabetes, which makes up the bulk of diabetes cases, is largely preventable and, in some cases, potentially reversible if identified and managed early in the disease course. However, all evidence indicates that diabetes prevalence is increasing worldwide, primarily due to a rise in obesity caused by multiple factors. Preventing and controlling type 2 diabetes remains an ongoing challenge. It is essential to better understand disparities in risk factor profiles and diabetes burden across populations, to inform strategies to successfully control diabetes risk factors within the context of multiple and complex drivers. Funding: Bill &amp; Melinda Gates Foundation.</p

The state of the Martian climate

60°N was +2.0°C, relative to the 1981–2010 average value (Fig. 5.1). This marks a new high for the record. The average annual surface air temperature (SAT) anomaly for 2016 for land stations north of starting in 1900, and is a significant increase over the previous highest value of +1.2°C, which was observed in 2007, 2011, and 2015. Average global annual temperatures also showed record values in 2015 and 2016. Currently, the Arctic is warming at more than twice the rate of lower latitudes

Factors that transformed maize productivity in Ethiopia

Published online: 26 July 2015Maize became increasingly important in the food security of Ethiopia following the major drought and famine that occurred in 1984. More than 9 million smallholder house- holds, more than for any other crop in the country, grow maize in Ethiopia at present. Ethiopia has doubled its maize produc- tivity and production in less than two decades. The yield, currently estimated at >3 metric tons/ha, is the second highest in Sub-Saharan Africa, after South Africa; yield gains for Ethiopia grew at an annual rate of 68 kg/ha between 1990 and 2013, only second to South Africa and greater than Mexico, China, or India. The maize area covered by improved varieties in Ethiopia grew from 14 % in 2004 to 40 % in 2013, and the application rate of mineral fertilizers from 16 to 34 kg/ ha during the same period. Ethiopia ’ s extension worker to farmer ratio is 1:476, compared to 1:1000 for Kenya, 1:1603 for Malawi and 1:2500 for Tanzania. Increased use of im- proved maize varieties and mineral fertilizers, coupled with increased extension services and the absence of devastating droughts are the key factors promoting the accelerated growth in maize productivity in Ethiopia. Ethiopia took a homegrown solutions approach to the research and development of its maize and other commodities. The lesson from Ethiopia ’ s experience with maize is that sustained investment in agricul- tural research and development and policy support by the national government are crucial for continued growth of agricultur