Diurnal and Interannual Variability of Rainfall in Nigeria Climatic Zones as Seen from In-situ and Satellite Measurements

Rainfall has been considered as a key indicator of changes in the climate and important factor of flood. Its measurements are important for climate change assessment on the water cycle and water balance of the world while her intensities monitoring are necessary for flood predictions. This study investigated the variation of Rainfall Intensity and Rainfall depth in Nigeria climatic zones and to predict the reoccurrence of such type of rainfall for planning purposes. The climatic zones of Nigeria were grouped into four; Coastal, Rain forest, Savannah and Sahel. The Rainfall data used in this study were collected in five minutes average for rainfall intensity for years 2007 to 2015 from Centre for Atmospheric Research (CAR-NASRDA) using Automatic Weather Stations and Tropical Rain Measuring Mission (TRMM) of NASA while monthly rainfall depth of 1980 to 2010 from Nigeria Meteorological Agency (NiMet). The Intensity was converted from mm/5mins to mm/h followed by diurnal values over the months and annual rainfall amounts were derived from the monthly rainfall depth for variability and probability analysis. Statistical analyses were performed using SPSS package to further ascertain the deviations from normal rainfall pattern. The Result shows that short and violent rain (> 50mm/h) are more frequent in the Savannah and Sahel zones compared to Rain forest and Coastal zones where prolonged and light rain (< 2.5mm/h) persist. The Coastal zone experience the highest precipitation of 2823.50 mm while the least precipitation of 925.70 mm occurred in the Sahel during the period considered with some fluctuations within the zones. The decadal wetter trend zone is the Sahel with an increment in rainy of more than 200mm and other zones rainfall increase by nothing less than 50mm of rain since 1980s. The occurrence of yearly rainfall like these could be predicted using the probability curve generated from the annual rainfall values. Keywords: rainfall, climatic zones, intensity, depth, probabilit

Zebrafish macroH2A variants have distinct embryo localization and function

Mouse and cell-based studies have shown that macroH2A histone variants predominantly associate with heterochromatin. Functional studies found that macroH2As are involved in gene repression, inhibiting the acquisition of pluripotency and preserving cell differentiation. However, only a few studies have analysed the role of macroH2A during early embryo development. We report the development of transgenic zebrafish lines expressing macroH2A isoforms (mH2A1 and mH2A2) fusion proteins (with GFP) under identified endogenous promoters. We found that mH2A1 and mH2A2 have different spatial and temporal expression patterns during embryonic development. mH2A1 is expressed mostly in the extraembryonic Yolk Syncytial Layer (YSL) starting before shield stage and decreasing once morphogenesis is completed. mH2A2 expression lags behind mH2A1, becoming evident at 24 hpf, within the whole body of the embryo proper. Our ChIP-seq analysis showed that mH2A1 and mH2A2 bind to different DNA regions, changing dramatically after gastrulation. We further analysed RNA-seq data and showed that there is not a general/unspecific repressing function of mH2A1 or mH2A2 associated with heterochromatin but a fine regulation depending on cell types and stage of development. mH2A1 downregulates DNA expression in specific cells and embryo stages and its effect is independent of heterochromatin formation but it is correlated with nucleus quiescence instead. Whereas mH2A2 DNA association correlates with upregulation of differentially expressed genes between 75% epiboly and 24 hpf stages. Our data provide information for underlying molecules that participate in crucial early developmental events, and open new venues to explore mH2A related mechanisms that involve cell proliferation, differentiation, migration and metabolism

Microfluidic Microcirculation Mimetic as a Tool for the Study of Rheological Characteristics of Red Blood Cells in Patients with Sickle Cell Anemia

Sickle cell disorder (SCD) is a multisystem disease with heterogeneous phenotypes. Al- though all patients have the mutated hemoglobin (Hb) in the SS phenotype, the severity and frequency of complications are variable. When exposed to low oxygen tension, the Hb molecule becomes dense and forms tactoids, which lead to the peculiar sickled shapes of the affected red blood cells, giving the disorder its name. This sickle cell morphology is responsible for the profound and widespread pathologies associated with this disorder, such as vaso-occlusive crisis (VOC). How much of the clinical manifestation is due to sickled erythrocytes and what is due to the relative contributions of other elements in the blood, especially in the microcapillary circulation, is usually not visualized and quantified for each patient during clinical management. Here, we used a microfluidic microcirculation mimetic (MMM), which has 187 capillary-like constrictions, to impose deformations on erythrocytes of 25 SCD patients, visualizing and characterizing the morpho-rheological properties of the cells in normoxic, hypoxic (using sodium meta-bisulfite) and treatment conditions (using hydroxyurea). The MMM enabled a patient-specific quantification of shape descriptors (circularity and roundness) and transit time through the capillary constrictions, which are readouts for morpho-rheological proper- ties implicated in VOC. Transit times varied significantly (p < 0.001) between patients. Our results demonstrate the feasibility of microfluidics-based monitoring of individual patients for personalized care in the context of SCD complications such as VOC, even in resource-constrained setting

Introduction of Mobile Health Tools to Support COVID-19 Training and Surveillance in Ogun State Nigeria

Mobile health (mhealth) tools delivered through wireless technology are emerging as effective strategies for delivering quality training, ensuring rapid clinical decision making, and monitoring implementation of simple and effective interventions in under-resourced settings. We share our early experience of developing and deploying the InStrat COVID-19 health worker training application (App) in Ogun State, Western Nigeria where the country's first COVID-19 case was reported. This App was designed to directly provide frontline health workers with accurate and up-to-date information about COVID-19; enable them to quickly identify, screen and manage COVID-19 suspects; provide guidance on specimen collection techniques and safety measures to observe within wards and quarantine centers dealing with COVID-19. The App was deployed in 271 primary health care facilities in Ogun state and a total of 311 health workers were trained to use it. Of the 123 health workers who completed knowledge pre- and post-tests, their average test score improved from 47.5 (±9.4) to 73.1(±10.0) %, P < 0.0001 after using the tutorial. Rapid adoption and uptake were driven largely by public-private sector involvement as well as certification of health workers with reported satisfaction levels of over 95% among those who completed pre- and post-test surveys. Challenges encountered included a lack of universal availability of android phones for frontline health workers, lack of internet access in remote areas and a need to incentivize the workers. The timely deployment of this App targeting primary health care workers, mostly in hard-to-reach areas, obviated the need for conventional didactic training with potential of savings in training costs and time and could be applied to similar contexts

Effects of gamma irradiation and ethyl methane sulphonate on morphometric traits and prevalence of common viral diseases and whiteflies in cassava

Cassava ( Manihot esculenta Crantz) is an important staple and food security crop for millions of people in Africa. However, its nutritional value is limited; yet its productivity is constrained by several pests and diseases. Induced mutagenesis is one approach with the potential to overcome such biotic stresses. The objective of this study was to assess the variability in morphometric traits and prevalence of common viral diseases and whiteflies in cassava to different doses and concentrations of gamma irradiation and ethyl methane sulphonate (ems) treatments. The effects were assessed on seed germination and growth of stakes, as well as foliar viral disease symptoms and whitefly counts. Radio-sensitivity tests revealed LD50 for sprouting as 37.6Gy for \u3b3-irradiation and 0.08% for EMS treatment. There was notable decrease in sprout, epicotyl length, shoot height, petiole length and number of leaf lobes, with increasing \u3b3-ray doses and EMS concentrations. Contrastingly, total chlorophyll content increased with increasing doses of \u3b3-rays and EMS concentrations. Basing on foliar whitefly counts and disease symptoms, there was a general increase in susceptibility to whitefly infestation and cassava mosaic disease (CMD) incidence. Significantly varying levels of resistance or tolerance to whiteflies and CMD were observed among plantlets derived from irradiated and EMS treated stems, compared to the controls. These findings lay a foundation for more future research on breeding for various traits, including disease resistance in cassava using induced mutagenesis approach.Le manioc ( Manihot esculenta Crantz) est une culture de base et de la s\ue9curit\ue9 alimentaire importante pour des millions de personnes en Afrique. Cependant, sa valeur nutritionnelle est limit\ue9e; pourtant, sa productivit\ue9 est limit\ue9e par plusieurs ravageurs et maladies. La mutagen\ue8se induite est une approche ayant le potentiel de surmonter de tels stress biotiques. L\u2019objectif de cette \ue9tude \ue9tait d\u2019\ue9valuer la variabilit\ue9 des traits morphom\ue9triques et la pr\ue9valence des maladies virales courantes et des aleurodes du manioc en raison de l\u2019exposition \ue0 diff\ue9rentes doses et concentrations des traitements par l\u2018 irradiation gamma et \ue9thyl m\ue9thane sulfonate (EMS). Les effets ont \ue9t\ue9 \ue9valu\ue9s sur la germination des graines et la croissance des tuteurs, ainsi que sur les sympt\uf4mes de la maladie virale foliaire et le nombre des aleurodes. Les tests de radiosensibilit\ue9 ont r\ue9v\ue9l\ue9 que la DL50 pour la germination \ue9tait de 37,6 Gy pour l\u2019irradiation et de 0,08 % pour le traitement EMS. Il y avait une diminution notable de la pousse, de la longueur de l\u2019\ue9picotyle, de la hauteur des pousses, de la longueur du p\ue9tiole et du nombre des lobes foliaires, avec l\u2019augmentation des doses de rayons et des concentrations EMS. En revanche, la teneur totale en chlorophylle augmentait avec l\u2019augmentation des doses de rayons et des concentrations EMS. Sur la base des d\ue9nombrements foliaires des aleurodes et des sympt\uf4mes de la maladie, il y avait une susceptibilit\ue9 g\ue9n\ue9ralement accrue \ue0 l\u2019infestation des aleurodes et \ue0 l\u2019incidence de la maladie de la mosa\uefque du manioc (CMD). Des niveaux significativement variables de r\ue9sistance ou de tol\ue9rance aux aleurodes et \ue0 la CMD ont \ue9t\ue9 observ\ue9s parmi les plantules d\ue9riv\ue9es de tiges irradi\ue9es et trait\ue9es par EMS, par rapport aux t\ue9moins. Ces r\ue9sultats jettent les bases des autres recherches futures sur la s\ue9lection pour les divers caract\ue8res, y compris la r\ue9sistance aux maladies du manioc en utilisant une approche de mutagen\ue8se induite

Evolutionary distances in the twilight zone -- a rational kernel approach

Phylogenetic tree reconstruction is traditionally based on multiple sequence alignments (MSAs) and heavily depends on the validity of this information bottleneck. With increasing sequence divergence, the quality of MSAs decays quickly. Alignment-free methods, on the other hand, are based on abstract string comparisons and avoid potential alignment problems. However, in general they are not biologically motivated and ignore our knowledge about the evolution of sequences. Thus, it is still a major open question how to define an evolutionary distance metric between divergent sequences that makes use of indel information and known substitution models without the need for a multiple alignment. Here we propose a new evolutionary distance metric to close this gap. It uses finite-state transducers to create a biologically motivated similarity score which models substitutions and indels, and does not depend on a multiple sequence alignment. The sequence similarity score is defined in analogy to pairwise alignments and additionally has the positive semi-definite property. We describe its derivation and show in simulation studies and real-world examples that it is more accurate in reconstructing phylogenies than competing methods. The result is a new and accurate way of determining evolutionary distances in and beyond the twilight zone of sequence alignments that is suitable for large datasets.Comment: to appear in PLoS ON

Rohlin Distance and the Evolution of Influenza A virus: Weak Attractors and Precursors

The evolution of the hemagglutinin amino acids sequences of Influenza A virus is studied by a method based on an informational metrics, originally introduced by Rohlin for partitions in abstract probability spaces. This metrics does not require any previous functional or syntactic knowledge about the sequences and it is sensitive to the correlated variations in the characters disposition. Its efficiency is improved by algorithmic tools, designed to enhance the detection of the novelty and to reduce the noise of useless mutations. We focus on the USA data from 1993/94 to 2010/2011 for A/H3N2 and on USA data from 2006/07 to 2010/2011 for A/H1N1 . We show that the clusterization of the distance matrix gives strong evidence to a structure of domains in the sequence space, acting as weak attractors for the evolution, in very good agreement with the epidemiological history of the virus. The structure proves very robust with respect to the variations of the clusterization parameters, and extremely coherent when restricting the observation window. The results suggest an efficient strategy in the vaccine forecast, based on the presence of "precursors" (or "buds") populating the most recent attractor.Comment: 13 pages, 5+4 figure

Reprogrammed Transcriptome in Rhesus-Bovine Interspecies Somatic Cell Nuclear Transfer Embryos

Global activation of the embryonic genome (EGA), one of the most critical steps in early mammalian embryo development, is recognized as the time when interspecies somatic cell nuclear transfer (iSCNT) embryos fail to thrive.In this study, we analyzed the EGA-related transcriptome of rhesus-bovine iSCNT 8- to 16-cell embryos and dissected the reprogramming process in terms of embryonic gene activation, somatic gene silencing, and maternal RNA degradation. Compared with fibroblast donor cells, two thousand and seven genes were activated in iSCNT embryos, one quarter of them reaching expression levels comparable to those found in in vitro fertilized (IVF) rhesus embryos. This suggested that EGA in iSCNT embryos had partially recapitulated rhesus embryonic development. Eight hundred and sixty somatic genes were not silenced properly and continued to be expressed in iSCNT embryos, which indicated incomplete nuclear reprogramming. We compared maternal RNA degradation in bovine oocytes between bovine-bovine SCNT and iSCNT embryos. While maternal RNA degradation occurred in both SCNT and iSCNT embryos, we saw more limited overall degradation of maternal RNA in iSCNT embryos than in SCNT embryos. Several important maternal RNAs, like GPF9, were not properly processed in SCNT embryos.Our data suggested that iSCNT embryos are capable of triggering EGA, while a portion of somatic cell-associated genes maintain their expression. Maternal RNA degradation seems to be impaired in iSCNT embryos. Further understanding of the biological roles of these genes, networks, and pathways revealed by iSCNT may expand our knowledge about cell reprogramming, pluripotency, and differentiation

Mst1/2 signalling to Yap: gatekeeper for liver size and tumour development

The mechanisms controlling mammalian organ size have long been a source of fascination for biologists. These controls are needed to both ensure the integrity of the body plan and to restrict inappropriate proliferation that could lead to cancer. Regulation of liver size is of particular interest inasmuch as this organ maintains the capacity for regeneration throughout life, and is able to regain precisely its original mass after partial surgical resection. Recent studies using genetically engineered mouse strains have shed new light on this problem; the Hippo signalling pathway, first elucidated as a regulator of organ size in Drosophila, has been identified as dominant determinant of liver growth. Defects in this pathway in mouse liver lead to sustained liver overgrowth and the eventual development of both major types of liver cancer, hepatocellular carcinoma and cholangiocarcinoma. In this review, we discuss the role of Hippo signalling in liver biology and the contribution of this pathway to liver cancer in humans

Stable interference of EWS–FLI1 in an Ewing sarcoma cell line impairs IGF-1/IGF-1R signalling and reveals TOPK as a new target

BACKGROUND: Ewing sarcoma is a paradigm of solid tumour -bearing chromosomal translocations resulting in fusion proteins that act as deregulated transcription factors. Ewing sarcoma translocations fuse the EWS gene with an ETS transcription factor, mainly FLI1. Most of the EWS–FLI1 target genes still remain unknown and many have been identified in heterologous model systems