153 research outputs found
Reproductive biology of the common torpedo, Torpedo torpedo (Linnaeus, 1758) (Pisces, Torpedinidae) from the coast of Senegal (Eastern Tropical Atlantic)
Among the five species of genus Torpedo recorded from the coast of Senegal, the common torpedo, Torpedo torpedo is that most cornrnonly caught in the area. Adult males and fernales studied were over 300 mm and 310 mm total length (TL), respectively, with the largest male and the largest female recorded being 445 mm and 550 mm TL respectively. Size at birth was between 102 and 125 mm TL (mean 112.12 mm; s.e.m. 5.58). Weight of eggs ranged frorn 6.2 to 8.0 g (rnean: 7.07; s.e.m. 0.5). Gestation lasts longer, from 6 to 8 rnonths, than in the Mediterranean specimens. A calculated chernical balance of development based on rnean dry weights of the fully developed fetuses and ripe oocytes was 1.58 for T. torpedo. This value shows that this torpedinid is not a pure lecithotrophic species, and the role of the rnother during gestation is not negligible. The fecundity (s.1.) of T. torpedo ranges from 5 to 28 in Senegalese specimens as cornpared to 1 to 9 in Mediterranean specirnens. Male ernbryos and fully developed fetuses are more nurnerous than fernales. Among the free-living specimens, nurnber of males and fernales is practically the same. The cornrnon torpedos from the coast of Senegal are larger and the eggs are heavier than Mediterranean specirnens.
Key words: Pisces, Torpedinidae, Torpedo torpedo, Reproductive biology, Senegal, Eastern Tropical Atlantic.Among the five species of genus Torpedo recorded from the coast of Senegal, the common torpedo, Torpedo torpedo is that most cornrnonly caught in the area. Adult males and fernales studied were over 300 mm and 310 mm total length (TL), respectively, with the largest male and the largest female recorded being 445 mm and 550 mm TL respectively. Size at birth was between 102 and 125 mm TL (mean 112.12 mm; s.e.m. 5.58). Weight of eggs ranged frorn 6.2 to 8.0 g (rnean: 7.07; s.e.m. 0.5). Gestation lasts longer, from 6 to 8 rnonths, than in the Mediterranean specimens. A calculated chernical balance of development based on rnean dry weights of the fully developed fetuses and ripe oocytes was 1.58 for T. torpedo. This value shows that this torpedinid is not a pure lecithotrophic species, and the role of the rnother during gestation is not negligible. The fecundity (s.1.) of T. torpedo ranges from 5 to 28 in Senegalese specimens as cornpared to 1 to 9 in Mediterranean specirnens. Male ernbryos and fully developed fetuses are more nurnerous than fernales. Among the free-living specimens, nurnber of males and fernales is practically the same. The cornrnon torpedos from the coast of Senegal are larger and the eggs are heavier than Mediterranean specirnens.
Key words: Pisces, Torpedinidae, Torpedo torpedo, Reproductive biology, Senegal, Eastern Tropical Atlantic.Among the five species of genus Torpedo recorded from the coast of Senegal, the common torpedo, Torpedo torpedo is that most cornrnonly caught in the area. Adult males and fernales studied were over 300 mm and 310 mm total length (TL), respectively, with the largest male and the largest female recorded being 445 mm and 550 mm TL respectively. Size at birth was between 102 and 125 mm TL (mean 112.12 mm; s.e.m. 5.58). Weight of eggs ranged frorn 6.2 to 8.0 g (rnean: 7.07; s.e.m. 0.5). Gestation lasts longer, from 6 to 8 rnonths, than in the Mediterranean specimens. A calculated chernical balance of development based on rnean dry weights of the fully developed fetuses and ripe oocytes was 1.58 for T. torpedo. This value shows that this torpedinid is not a pure lecithotrophic species, and the role of the rnother during gestation is not negligible. The fecundity (s.1.) of T. torpedo ranges from 5 to 28 in Senegalese specimens as cornpared to 1 to 9 in Mediterranean specirnens. Male ernbryos and fully developed fetuses are more nurnerous than fernales. Among the free-living specimens, nurnber of males and fernales is practically the same. The cornrnon torpedos from the coast of Senegal are larger and the eggs are heavier than Mediterranean specirnens.
Key words: Pisces, Torpedinidae, Torpedo torpedo, Reproductive biology, Senegal, Eastern Tropical Atlantic
The spread of tick-borne borreliosis in West Africa and its relationship to sub-saharan drought
Zoonotic abbreviata caucasica in wild chimpanzees (Pan troglodytes verus) from Senegal
Abbreviata caucasica (syn. Physaloptera mordens) has been reported in human and various non-human primates including great apes. The identification of this nematode is seldom performed and relies on egg characterization at the coproscopy, in the absence of any molecular tool. Following the recovery of two adult females of A. caucasica from the feces of wild Senegalese chimpanzees, morphometric characteristics were reported and new data on the width of the esophagus (0.268â 0.287 mm) and on the cuticle structure (0.70â0.122 mm) were provided. The molecular characterization of a set of mitochondrial (cox1, 16S rRNA, 12S rRNA) and nuclear (18S rRNA and ITS2) partial genes was performed. Our phylogenetic analysis indicates for the first time that A. caucasica is monophyletic with Physaloptera species. A novel molecular tool was developed for the routine diagnosis of A. caucasica and the surveillance of Nematoda infestations. An A. caucasica-specific qPCR targeting the 12S gene was assessed. The assay was able to detect up to 1.13 Ă 10â3 eggs/g of fecal matter irrespective of its consistency, with an efficiency of 101.8% and a perfect adjustment (R2 = 0.99). The infection rate by A. caucasica in the chimpanzee fecal samples was 52.08%. Only 6.19% of the environmental samples were positive for nematode DNA and any for A. caucasica. Our findings indicate the need for further studies to clarify the epidemiology, circulation, life cycle, and possible pathological effects of this infestation using the molecular tool herein developed
Special symplectic Lie groups and hypersymplectic Lie groups
A special symplectic Lie group is a triple such that
is a finite-dimensional real Lie group and is a left invariant
symplectic form on which is parallel with respect to a left invariant
affine structure . In this paper starting from a special symplectic Lie
group we show how to ``deform" the standard Lie group structure on the
(co)tangent bundle through the left invariant affine structure such
that the resulting Lie group admits families of left invariant hypersymplectic
structures and thus becomes a hypersymplectic Lie group. We consider the affine
cotangent extension problem and then introduce notions of post-affine structure
and post-left-symmetric algebra which is the underlying algebraic structure of
a special symplectic Lie algebra. Furthermore, we give a kind of double
extensions of special symplectic Lie groups in terms of post-left-symmetric
algebras.Comment: 32 page
Ethnobotanical study of cowpea (Vigna unguiculata (L.) Walp.) in Senegal
Open Access Article; Published online: 05 Feb 2022Cowpea (Vigna unguiculata) plays a key role in family farming systems in Senegal. It makes an essential contribution to economic, nutritional and food security. Although it is crucial, little is known about how farmers classify the diversity of local varieties or about the social practices associated with them. The aim of this study is to characterize the farming practices associated with growing cowpea in Senegal. Surveys were conducted involving 335 rural farmers living in 37 villages, spread across seven regions that produce cowpea. An average of ten farmers were randomly selected in each village. The results reveal that cowpea is a key feature of cropping systems in the studied area. Our findings highlight the high diversity of local cowpea varieties with 59 local names inventoried. In 75% of cases, the name refers to the seedâs morphology or color. Cowpea production is more diverse in Diourbel and Louga and less diverse in the south. More than half the farmers (57%) acquired their cowpea seeds (early, semi-early and late maturity varieties) outside their village, either from markets, seed suppliers or NGOs. This new understanding of farmersâ expertize in the management of cowpea and its local variability will help to valorize local diversity in breeding programs
Racial Disparities in Surgical Outcomes after Mastectomy in 223,000 Female Breast Cancer Patients - A Retrospective Cohort Study
BACKGROUND: Breast cancer mortality and treatment differ across racial groups. It remains unclear whether such disparities are also reflected in perioperative outcomes of breast cancer patients undergoing mastectomy.
STUDY DESIGN: We reviewed the American College of Surgeons National Surgical Quality Improvement Program (ACS-NSQIP) database (2008-2021) to identify female patients who underwent mastectomy for oncological purposes. The outcomes were stratified by five racial groups (white, Black/African American, Asian, American Indian/Alaska Native, and Native Hawaiian/Pacific Islander) and included 30-day mortality, reoperation, readmission, surgical and medical complications, and non-home discharge.
RESULTS: The study population included 222,947 patients, 68% (n=151,522) of whom were white, 11% (n=23,987) Black/African American, 5% (n=11,217) Asian, 0.5% (n=1,198) American Indian/Alaska Native, and 0.5% (n=1,018) Native Hawaiian/Pacific Islander. While 136,690 (61%) patients underwent partial mastectomy, 54,490 (24%) and 31,767 (14%) women received simple and radical mastectomy, respectively. Overall, adverse events occurred in 17, 222 (7.7%) patients, the largest portion of which were surgical complications (n=7,246; 3.3%). Multivariable analysis revealed that being of Asian race was protective against perioperative complications (OR=0.71; P<0.001), whereas American Indian/Alaska Native women were most vulnerable to the complication occurrence (OR=1.41; P<0.001). Black/African American patients had a significantly lower risk of medical (OR=0.59; P<0.001) and surgical complications (OR=0.60; P<0.001) after partial and radical mastectomy, respectively, their likelihood of readmission (OR=1.14; P=0.045) following partial mastectomy was significantly increased.
CONCLUSION: We identified American Indian/Alaska Native women as particularly vulnerable to complications following mastectomy. Asian patients experienced the lowest rate of complications in the perioperative period. Our analyses revealed comparable confounder-adjusted outcomes following partial and complete mastectomy between Black and white races. Our findings call for care equalization in the field of breast cancer surgery
The role of tolerant genotypes and plant nutrients in the management of iron toxicity in lowland rice
Iron toxicity is a nutrient disorder associated with high concentrations of iron in soil solutions. Deficiencies of other nutrients, such as P, K, Ca, Mg and Zn, have been implicated in its occurrence in rice plants. Field experiments were carried out in 1992 and 1993 in Ivory Coast to evaluate the iron toxicity tolerance of promising rice cultivars available in West Africa, and to provide additional information for selecting breeding materials. Two sites, differing in their potential to cause iron toxicity, were used. Glasshouse and field studies were also conducted to test the role of other nutrients in the occurrence of iron toxicity. The results showed that genetic tolerance to iron toxicity can significantly improve rice production in iron-toxic soils, with some cultivars producing yields in excess of 5 t/ha. The application of N, P, K and Zn in the field decreased the uptake of iron in rice tops, and this can be a significant factor in the iron-toxicity tolerance of the cultivars
COMBINING ABILITY AND HETEROTIC PATTERN IN WEST AFRICAN SORGHUM LANDRACES
Heterotic grouping based on combining ability for traits of interest,
in addition to plant performance and genetic relationship among
germplasm, would be useful in planning crosses in breeding programmes.
This study aimed at determining the combining abilities of selected
landraces for morphological and physiological traits under contrasted
environments and identifying the suitable heterotic grouping method for
superior hybrid production. For this purpose, nineteen accessions
representing different origins and population structure among West
African Sorghum Accessions Panel (WASAP) and two female lines, were
used in \uab\ua0Line x tester\ua0\ubb mating design to produce
thirty-eight (38) hybrids. Analysis of variance showed significant
general combining ability and specific combining ability effects for
grain weight, plant height, days to flowering, panicle length and
chlorophyll content implying existence of heterotic responses for these
traits. Both additive and non-additive gene effects were important in
controlling the inheritance of the traits. Parents K31.3, K37 and Ni331
were the best combiners for grain weight, providing the opportunity for
breeders to improve grain yield under diverse environments. AVG-1 x
K31.3 and AVG-1 x Tg148 were the superior hybrids. Combining ability
based heterotic grouping methods classified sorghum accessions into
four groups. The heterotic group\u2019s specific and general combining
ability (HSGCA) method was the suitable in predicting hybrid
superiority. This combining abilities based heterotic grouping study is
an additional tool that breeders could use to identify the best parents
for superior hybrids development in West Africa.La d\ue9termination des groupes h\ue9t\ue9rotiques bas\ue9e sur
les aptitudes \ue0 la combinaison des traits
d\u2019int\ue9r\ueat en plus des performances et des relations
g\ue9n\ue9tiques dans une collection est importante pour planifier
les croisements en s\ue9lection. Cette visait la d\ue9termination
des aptitudes \ue0 la combinaison des accessions locales pour
certains traits morphologiques sous environnements contrast\ue9s et
l\u2019identification de la meilleure m\ue9thode dans la
pr\ue9diction de la vigueur hybride. Dans cette perspective, dix-neuf
accessions repr\ue9sentant diff\ue9rentes origines et la structure
de la population d\u2019un panel ouest africain de sorgho (WASAP) et
deux m\ue2les st\ue9riles ont \ue9t\ue9 utilis\ue9s dans un
croisement \uab\ua0Line x tester\ua0\ubb pour produire
trente-huit hybrides F1, objet de cette \ue9tude. L\u2019analyse de
variance a indiqu\ue9 des effets significatifs de l\u2019aptitude
g\ue9n\ue9rale et sp\ue9cifique \ue0 la combinaison pour le
poids grain, la hauteur plante, la dur\ue9e semis floraison et la
concentration en chlorophylle traduisant l\u2019existence des
r\ue9ponses h\ue9t\ue9rotiques pour ces traits. Les effets
g\ue9niques additif et non-additif ont \ue9t\ue9 importants dans
le contr\uf4le de ces caract\ue8res. K31.3, K37 et Ni331
pr\ue9sentent les meilleures aptitudes g\ue9n\ue9rales \ue0 la
combinaison puis AVG-1 x K31.3 et AVG-1 x Tg148 ont \ue9t\ue9 les
meilleurs hybrides pour le poids grains. Ils constituent une
opportunit\ue9 pour l\u2019am\ue9lioration dans divers
environnements. Les diff\ue9rentes m\ue9thodes ont class\ue9 les
accessions de sorgho en quatre groupes. Le groupage bas\ue9 sur la
m\ue9thode HSGCA accroit l\u2019efficience en s\ue9lection de 15
%. Cette \ue9tude offre un outil d\u2019aide pour les
s\ue9lectionneurs dans le choix des meilleurs parents \ue0 croiser
pour la production des hybrides sup\ue9rieurs en Afrique de
l\u2019Ouest
The effects of zooprophylaxis and other mosquito control measures against malaria in Nouna, Burkina Faso
<p>Abstract</p> <p>Background</p> <p>In the absence of large scale, organized vector control programmes, individual protective measures against mosquitoes are essential for reducing the transmission of diseases like malaria. Knowledge of the types and effectiveness of mosquito control methods used by households can aid in the development and promotion of preventive measures.</p> <p>Methods</p> <p>A matched, population-based case control study was carried out in the semi-urban region of Nouna, Burkina Faso. Surveys and mosquito captures were conducted for each participating household. Data were analysed using conditional logistic regression and Pearson's product-moment correlations.</p> <p>Results</p> <p>In Nouna, Burkina Faso, the main types of reported mosquito control measures used included sleeping under bed nets (insecticide-treated and untreated) and burning mosquito coils. Most of the study households kept animals within the compound or house at night. Insecticide house sprays, donkeys, rabbits and pigs were significantly associated with a reduced risk of malaria only in univariate analyses.</p> <p>Conclusion</p> <p>Given the conflicting results of the effects of zooprophylaxis from previous studies, other community-based preventive measures, such as bed nets, coils and insecticide house-spraying, may be of more benefit.</p
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