482 research outputs found
Influence of plant population on fruit and seed yield characters of cayenne pepper (Capsicum frutescens L.) genotypes
This study assessed the influence of three plant populations (18518, 27777 and 40000 plants ha-1) on fruit and seed yield characters in 16 genotypes of Capsicum frutescens in 2010 and 2011 cropping years using a 3 x 16 split plot arrangement fitted into a randomized complete block design. Plant population and genotype formed main and sub-plots, respectively. Data collected on fruit and seed yield characters were subjected to analysis of variance after which means were separated using Fisher’s Least Significant Difference. Correlation analysis was also carried out among the characters. Significant and highest (P < 0.01) number of fruits per plant, single fruit weight, fruit weight per plant, number of seeds per fruit, 100 seed weight, seed weight per plant and seed weight per fruit were obtained under 18518 plants ha-1 while highest (P < 0.05) fruit yield ha-1 (11.3 tons) and seed yield ha-1 (698.7 kg) were obtained under 40000 plants ha-1. Top fruit and seed yielding genotypes across the three plant population were PP9955-15 and Chilli 14, respectively. Number of fruits per plant showed negative and highly significant correlation with single fruit weight, fruit length, fruit width, number of seeds per fruit, 100-seed weight and seed weight per fruit. Significant positive or negative correlations were also observed among other characters. Plant population of 40,000 ha-1 using 50 x 50 cm spacing is recommended for high fruit and seed yield in C. frutescens production.Key words: Cayenne pepper, plant population, seed production efficiency, seed yiel
A comprehensive approach to simulation of cartridge filtration using CFD
Household water treatment (HWT) systems are widely used for the provision of potable water in many countries with their low-cost key to attaining universal and equitable access to safe and affordable drinking water, Sustainable Development Goal 6.1. Removal of suspended particles (turbidity) from water sources via cartridge filters is often the first step of a HWT system, with the primary treatment increasing the efficiency of a subsequent disinfection step. Whilst the performance of cartridge filters (removal efficiency and pressure drop) can be determined experimentally in long experiments with high volumes of water, numerical simulation adds fundamental insight to the influence of fluid dynamics on particle deposition and vice versa. In this study, a novel computational fluid dynamic (CFD) model was developed to simulate the fundamental mechanisms underpinning the removal of particles within the widely used 10 in. cartridge filter, informed by and complemented with laboratory validation. The Eulerian approach was used to simulate fluid flow with the Lagrangian approach adopted for particle tracking. Rosin-Rammler distribution was implemented with respect to the particle size distribution of the diatomaceous earth particles used in the experiments. Given particles were non-spherical (disk shape), Wadell's sphericity was included to account for the effect of particle shape on drag force. A porous domain was implemented to simulate the filter element through addition of a source term to the momentum equations, with the likelihood of particle deposition, detachment and rebound also considered. Laboratory based validation studies confirmed the novel CFD model to accurately model removal of turbidity and predict the pressure drop across the filter with Root Mean Square Percentage Error (RMSPE) of less than 3%. The simulated location of particle deposition on the filter elements closely matched images taken at several stages during filtration experiments with the model aiding understanding of pattern of particle removal along and within the porous filter structure. This novel and comprehensive modelling methodology can be utilized to simulate the filtration process at the macro-scale, permitting evaluation of new filter designs and materials for advanced filtration systems; ultimately improving HWT system performance and reducing costs to users.</p
Family Unification in Five and Six Dimensions
In family unification models, all three families of quarks and leptons are
grouped together into an irreducible representation of a simple gauge group,
thus unifying the Standard Model gauge symmetries and a gauged family symmetry.
Large orthogonal groups, and the exceptional groups and have been
much studied for family unification. The main theoretical difficulty of family
unification is the existence of mirror families at the weak scale. It is shown
here that family unification without mirror families can be realized in simple
five-dimensional and six-dimensional orbifold models similar to those recently
proposed for SU(5) and SO(10) grand unification. It is noted that a family
unification group that survived to near the weak scale and whose coupling
extrapolated to high scales unified with those of the Standard model would be
evidence accessible in principle at low energy of the existence of small
(Planckian or GUT-scale) extra dimensions.Comment: 13 pages, 2 figures, minor corrections, references adde
Unification in 5D SO(10)
Gauge unification in a five dimensional supersymmetric SO(10) model
compactified on an orbifold is studied. One
orbifolding reduces N=2 supersymmetry to N=1, and the other breaks SO(10) to
the Pati-Salam gauge group \ps. Further breaking to the standard model gauge
group is made through the Higgs mechanism on one of the branes. The differences
of the three gauge couplings run logarithmically even in five dimensions and we
can keep the predictability for unification as in four dimensional gauge
theories. We obtain an excellent prediction for gauge coupling unification with
a cutoff scale GeV and a compactification scale
GeV. Finally, although proton decay due to
dimension 5 operators may be completely eliminated, the proton decay rate in
these models is sensitive to the placement of matter multiplets in the 5th
dimension, as well as to the unknown physics above the cutoff scale.Comment: 33 pages, one reference added and fig. 3 caption correcte
Electron-hole bilayer quantum dots: Phase diagram and exciton localization
We studied a vertical ``quantum dot molecule'', where one of the dots is
occupied with electrons and the other with holes. We find that different phases
occur in the ground state, depending on the carrier density and the interdot
distance. When the system is dominated by shell structure, orbital degeneracies
can be removed either by Hund's rule, or by Jahn-Teller deformation. Both
mechanisms can lead to a maximum of the addition energy at mid-shell. At low
densities and large interdot distances, bound electron-hole pairs are formed.Comment: 10 pages, 3 figure
Amplitudes With Different Helicity Configurations Of Noncommutative QED
The amplitudes of purely photonic and photon{2-fermion processes of non-
commutative QED (NCQED) are derived for different helicity configurations of
photons. The basic ingredient is the NCQED counterpart of Yang-Mills recursion
relations by means of Berends and Giele. The explicit solutions of recursion
relations for NCQED photonic processes with special helicity configurations are
presented.Comment: 23 pages, 2 figure
Two-Loop Diagrammatics in a Self-Dual Background
Diagrammatic rules are developed for simplifying two-loop QED diagrams with
propagators in a constant self-dual background field. This diagrammatic
analysis, using dimensional regularization, is used to explain how the fully
renormalized two-loop Euler-Heisenberg effective Lagrangian for QED in a
self-dual background field is naturally expressed in terms of one-loop
diagrams. The connection between the two-loop and one-loop vacuum diagrams in a
background field parallels a corresponding connection for free vacuum diagrams,
without a background field, which can be derived by simple algebraic
manipulations. It also mirrors similar behavior recently found for two-loop
amplitudes in N=4 SUSY Yang-Mills theory.Comment: 16 pp, Latex, Axodra
The reporting of studies conducted using observational routinely collected health data statement for pharmacoepidemiology (RECORD-PE).
In pharmacoepidemiology, routinely
collected data from electronic health
records (including primary care
databases, registries, and
administrative healthcare claims) are a
resource for research evaluating the
real world effectiveness and safety of
medicines. Currently available
guidelines for the reporting of research
using non-randomised, routinely
collected data—specifically the
REporting of studies Conducted using
Observational Routinely collected
health Data (RECORD) and the
Strengthening the Reporting of
OBservational studies in Epidemiology
(STROBE) statements—do not
capture the complexity of
pharmacoepidemiological research.
We have therefore extended the
RECORD statement to include
reporting guidelines specific to
pharmacoepidemiological research
(RECORD-PE). This article includes the
RECORD-PE checklist (also available on
www.record-statement.org) and
explains each checklist item with
examples of good reporting. We
anticipate that increasing use of the
RECORD-PE guidelines by researchers
and endorsement and adherence by
journal editors will improve the
standards of reporting of
pharmacoepidemiological research
undertaken using routinely collected
data. This improved transparency will
benefit the research community,
patient care, and ultimately improve
public health
The Importance of Context in Understanding Homelessness and Mental Illness: Lessons Learned From a Research Demonstration Project
Research reports on the housing outcomes for persons who are homeless and mentally ill have focused on client characteristics, program type, and services as independent variables, with mixed results. From social work practice, evaluation theory, and public policy perspectives, context is an important variable. Yet, it has received scant research attention in studies of the outcomes of persons who are mentally ill and homeless. This article summarizes research results from a demonstration project providing outreach or linkage services to this target population, illustrating the significant impact of context variables (site and recruitment source) on client characteristics, implementation, qualitative and quantitative service assessments, and housing outcomes. The discussion suggests how these contextual factors may operate, and it goes on to make recommendations to improve social work research and practice concerning the important dimensions of context that should be assessed.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/69136/2/10.1177_104973159800800203.pd
SUSY GUT Model Building
I discuss an evolution of SUSY GUT model building, starting with the
construction of 4d GUTs, to orbifold GUTs and finally to orbifold GUTs within
the heterotic string. This evolution is an attempt to obtain realistic string
models, perhaps relevant for the LHC. This review is in memory of the sudden
loss of Julius Wess, a leader in the field, who will be sorely missed.Comment: 24 pages, 14 figures, lectures given at PiTP 2008, Institute for
Advanced Study, Princeton, to be published in the European Physical Journal
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