4,459 research outputs found
Performance of nine cassava (Manihot esculanta Crantz) clones across three environments
The study was carried out to quantify the genotype Ă— environment interaction (G Ă— E) and to estimate the phenotypic stability by genotype genotype Ă— environment (GGE) biplot of nine cassava clones comprising 5 hybrids, 3 parent checks and 1 improved variety. The study was planted across three different environments; Fumesua, Pokuase and Ejura representing forest, coastal savanna and forest transition zones, respectively. Genotype main effect was significant (P < 0.001) for fresh root yield and dry matter content, G Ă— E interaction effect was significant (P < 0.001) for fresh root yield only and environment main effect was significant (P < 0.01) for only fresh root yield. The most stable clone for fresh root yield with above average performance was La02/026 (hybrid). The high genotype and low environment effects, and the relatively low interaction on dry matter content imply that evaluation and selection can be effectively done in fewer environments to select clones with high performance for the trait whiles fresh root yield requires multiple environments to identify clones with broad and specific adaptation
Genetic variability of three cassava traits across three locations in Ghana
A study was conducted to assess the extent of genetic variability, broad-sense heritability and correlations for fresh root weight, root number and top weight of five cassava genotypes across three locations in 2 years. Combined analysis of variance revealed highly significant genotypic effect for all the traits. Genotype x environment interaction was also significant for all the traits studied indicating considerable but, varying response of the genotypes to the environments. High broad-sense heritability and genetic advance as percent of the mean were observed for fresh root weight, suggesting that the trait is primarily under genetic control and that a simple recurrent phenotypic selection scheme would be rewarding. Phenotypic coefficients of variation values were larger than their corresponding genotypic coefficient of variation values for all traits. Correlations between the three traits were highly significant and positive indicating that simultaneous progress for the three traits is feasible
A selected ion flow tube study of the ion-molecule reactions of monochloroethene, trichloroethene and tetrachloroethene
Data for the rate coefficients and product cations of the reactions of a large number of atomic and small molecular cations with monochloroethene, trichloroethene and tetrachloroethene in a selected ion flow tube at 298 K are reported. The recombination energy of the ions range from 6.27 eV (HO) through to 21.56 eV (Ne). Collisional rate coefficients are calculated by modified average dipole orientation theory and compared with experimental values. Thermochemistry and mass balance predict the most feasible neutral products. Together with previously reported results for the three isomers of dichloroethene (J. Phys. Chem. A., 2006, 110, 5760), the fragment ion branching ratios have been compared with those from threshold photoelectron photoion coincidence spectroscopy over the photon energy range 9-22 eV to determine the importance or otherwise of long-range charge transfer. For ions with recombination energy in excess of the ionisation energy of the chloroethene, charge transfer is energetically allowed. The similarity of the branching ratios from the two experiments suggest that long-range charge transfer is dominant. For ions with recombination energy less than the ionisation energy, charge transfer is not allowed; chemical reaction can only occur following formation of an ion-molecule complex, where steric effects are more significant. The products that are now formed and their percentage yield is a complex interplay between the number and position of the chlorine atoms with respect to the C=C bond, where inductive and conjugation effects can be important
Referral of sexual violence against children: How do children and caregivers use a formal child protection mechanism in Harare, Zimbabwe?
Despite widespread expansion of policies to prevent and respond to violence over the past three decades, sexual violence against children remains common globally. Zimbabwe has expansive legal and policy frameworks to prevent, and formal services to respond to, sexual violence. Yet evidence is lacking about how children and caregivers use formal referral mechanisms. This study conducted secondary qualitative analysis of sexual violence cases [N=74] processed in Harare Magistrates Court and referred to Childline Zimbabwe, in October-November 2020, to examine which experiences children and/or their caregivers formally refer as sexual violence; how they perceive and manage these experiences; and how this relates to national policy contexts. Caregivers, particularly female, were central to reporting sexual violence. Data suggested that some forms of sexual violence were formally referred, including community sexual assault and abuse within families, however some adolescent girls faced blame and shame. There were gaps in reporting of sexual violence against boys, and sexual violence from dating partners or authority figures, with data suggesting that gendered stigma, shame, and fears of institutional authority, were barriers for reporting. Caregivers also reported consensual adolescent sexual relationships to police. These findings contribute to the limited evidence on forms of sexual violence that are and are not formally referred globally, and in sub-Saharan African settings. Existing policy frameworks in Zimbabwe can be strengthened around age of maturity, adolescent sexuality, sidelining of boy survivors, and the role of schools in child protection. Interventions should support caregivers’ efforts to report violence, while also addressing gendered blame and stigma, and stigmatisation of adolescent sexuality
Ambiguous loss and incomplete abduction narratives in Kosovo
Ten mothers of men and boys who were abducted and listed as missing during the war in Kosovo in 1998/1999 were interviewed in Kosovo in the spring of 2012. Although the missing are presumed dead by the authorities, the mothers continue to live in a state of emotional ambiguity where a presumption of death is balanced with the hope of being reunited. In the absence of absolute proof, finding the remains of their loved ones becomes a major preoccupation. Using a social phenomenological approach, this study explored the social and political complexities existing within the life-world of these women. The findings suggest that they live in a continual state of psychological distress, and even when remains are returned, the unknown elements of the narrative of their abduction and murder only add to their distress and force many into self-imposed emotional exile away from community and close family
Report of the Working Group on `W Mass and QCD' (Phenomenology Workshop on LEP2 Physics, Oxford, April 1997)
The W Mass and QCD Working Group discussed a wide variety of topics relating
to present and future measurements of M(W) at LEP2, including QCD backgrounds
to W+W- production. Particular attention was focused on experimental issues
concerning the direct reconstruction and threshold mass measurements, and on
theoretical and experimental issues concerning the four jet final state. This
report summarises the main conclusions.Comment: 43 pages LaTeX and 15 encapsulated postscript figures. Uses epsfig
and ioplppt macros. Full Proceedings to be published in Journal of Physics
CP Violation for Leptons at Higher Energy Scales
The phase convention independent measure of CP violation for three
generations of leptons is evaluated at different energy scales. Unlike in the
quark sector, this quantity does not vary much between the weak and the grand
unification scales. The behavior of the measure of CP violation in the Standard
Model is found to be different from that in the extensions of the Standard
Model.Comment: 10 pages, 2 figures, references added, typos correcte
Tracking crop varieties using genotypingbysequencing markers: a case study using cassava (Manihot esculenta Crantz)
GUTs in Curved Spacetime: Running Gravitational Constants, Newtonian Potential and the Quantum Corrected Gravitational Equations
The running coupling constants (in particular, the gravitational one) are
studied in asymptotically free GUTs and in finite GUTs in curved spacetime,
with explicit examples. The running gravitational coupling is used to calculate
the leading quantum GUT corrections to the Newtonian potential, which turn out
to be of logarithmic form in asymptotically free GUTs. A comparison with the
effective theory for the conformal factor ---where leading quantum corrections
to the Newtonian potential are again logarithmic--- is made. A totally
asymptotically free GUT with quantum higher derivative gravity is then
constructed, using the technique of introducing renormalization group (RG)
potentials in the space of couplings. RG equations for the cosmological and
gravitational couplings in this theory are derived, and solved numerically,
showing the influence of higher-derivative quantum gravity on the Newtonian
potential. The RG-improved effective gravitational Lagrangian for
asymptotically free massive GUTs is calculated in the strong (almost constant)
curvature regime, and the non-singular De Sitter solution to the quantum
corrected gravitational equations is subsequently discussed. Finally, possible
extensions of the results here obtained are briefly outlined.Comment: LaTeX, 27 pages, 2 uu-figure
Uncertainties in Coupling Constant Unification
The status of coupling constant unification in the standard model and its
supersymmetric extension are discussed. Uncertainties associated with the input
coupling constants, , threshold corrections at the low and high scales,
and possible nonrenormalizable operators are parametrized and estimated. A
simple parametrization of a general supersymmetric new particle spectrum is
given. It is shown that an effective scale can be defined, but for a
realistic spectrum it may differ considerably from the typical new particle
masses. The implications of the lower (higher) values of
suggested by low-energy (-pole) experiments are discussed.Comment: LaTex, 51 pages, 6 figures (available upon request), UPR-0513
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