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On the Extra Anomalous Gyromagnetic Ratio of the Electron and Other General Spin-1/2 Particles
No full textThis is an articleAs is well known, amongst the greatest successes of the Dirac equation at its birth
where its ability to naturally account for spin as a relativistic phenomenon and its almost arcane prediction of the correct gyromagnetic ratio of the Electron. The Dirac equation forms the most fundamental basis of Quantum Field Theory (QFT). QFT is one of the most successful fields of human endeavour. The Dirac equation gives an accurate account of the Electron so much that since its birth, it has always has been thought of as an equation for the Electron. However, in its bare and natural form, it is widely believed that the same can not be said of the Dirac equation when it comes to the Proton and Neutron, which ? as the Electron; are both spin-1/2 particles. For example, the Dirac equation has never in its natural form been
used to explain the gyromagnetic ratio of the Proton and Neutron. Much to the contrary to
this prevalent wisdom, here we show that one might account for the gyromagnetic ratio of any general spin-1/2 particle such as that of the Proton, Neutron, together with the Electron?s extra anomalous gyromagnetic ratio as second order effects within the minimally coupled Dirac theory that i.e., from the same theory that unveiled spin as a relativistic phenomenon and at the same time predicted the correct gyromagnetic ratio of the Electron.National University of Science & Technology (NUST)?s Research & Innovation Department and Research Board
Within-plant variation in defences in response to simulated herbivory in a semi-arid Southern African Savannah
No full textThis is an articleWithin-plant spatial variation in herbivore pressure can induce localized antiherbivory defence responses. We tested this hypothesis by studying branch-specific responses of Acacia robusta, Dichrostachys cinerea and
Ziziphus mucronata to simulated mammalian herbivory. Herbivory was simulated by clipping the terminal shoots(3 cm from tip) of tree branchlets, allowing them one year
of regrowth and then comparing their spine length and density and condensed tannins with those of adjacen tunclipped branchlets. Condensed tannin concentrations were higher in clipped branchlets than in unclipped
branchlets in all three woody species (P < 0.05). Spine length was higher in clipped branchlets than in unclipped branchlets in A. robusta (P < 0.05) but was similar in both
D. cinerea and Z. mucronata (P > 0.05). Spine density was double in clipped branchlets as compared to the unclipped branchlets in Z. mucronata (P < 0.05) but was similar in
both A. robusta and D. cinerea (P > 0.05). We found evidence of within-plant variation in condensed tannins concentration and spine length and density in response to simulated herbivory in the three woody species.International Foundation for Science, Stockholm, Sweden, through research grant D/4149-2
Is Relativity?s Equal Footing Treatment of Space and Time Correct in its Entirety?
No full textThis is an articleBoth the Special and General Theories of Relativity (hereafter: STR and
GTR respectively) put forward by Professor Albert Einstein enjoy an impressive, spectacular,
unparalleled and unprecedented success in explaining physical phenomenon as it
is revealed by experience. So successful are these theories ? so much that ? their very
foundations are no-longer questioned from a pessimist?s standpoint but from that of an
optimist? viewpoint. Any envisioned or proposed (new) experiment or observational measurement
is naturally expected to confirm the STR and GTR. Amongst the foundation
stones of the STR and GTR is the treatment of space and time on an equal footing. While
in-principle this treatment has no problem when dealing with reference frames, we urge
herein that this treat may not be correct when it comes to handling coordinate systems
e-Infrastructure and e-Services for Developing Countries: 6th International Conference, AFRICOMM
No full text6th International Conference, AFRICOMM 2014, Kampala, Uganda, November 24-25, 2014, Revised Selected PapersUnused spectrum in the television band (so-called TV white
space) has the potential to provide new spectrum for access to informa-
tion and communication services in developing countries. This claim has
been subject to a variety of measurement studies. The purpose of this
paper is to survey these studies to better characterize the spectrum that
is provided by TV white space. We discuss some of the challenges to such
studies and characterize the available TV white space spectrum in terms
of the total volume that is available
Removal of Pyrethrin from Aqueous Effluents by Adsorptive Micellar Flocculation
No full textThis is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.The equilibrium adsorption of pyrethrin onto aggregates formed by the flocculation of micelles of the surfactant sodium dodecyl
sulphate (SDS) with aluminium sulphate is reported.The experimental results were analysed using different adsorption isotherms
(Langmuir, Freundlich, Redlich-Peterson, Sips, Radke-Prausnitz, Temkin, linear equilibrium, and the Dubin-Radushkevich
isotherms). The Freundlich and linear equilibrium isotherms best describe the adsorption of pyrethrin onto SDS micellar
flocs, with the Freundlich adsorption constant, ?
?, and the mass distribution coefficient, ?
?, of 64.266 ((mg/g)(L/mg)1/?) and
119.65 L/g, respectively. Applicability of the Freundlich adsorption model suggests that heterogeneous surface adsorption affects
the adsorption. The mean free energy value estimated using the Dubinin-Radushkevich isotherm was 0.136 kJ/mol indicating that
physisorption may be predominant in the adsorption process
Glutathione S-transferase activity in the maize weevil, sitophilus zeamais (Mostch.)
No full textAn article with 4 pages.Glutathione S-transferase activities in field populalions (Fo) of the maize weevil,
Sitophilus zeamais, were compared with their 3rd generation (F,) progeny which
were reared in the laboratory. Two substrates, 1 -chloro-2,4-dinitrobenzene (CDNB)
i and glutathione (GSH) were used in the tests and the Michaelis constant (K,,,) was
determined for both these substrates. Enzyme activity was detected using the
CDNB as the model substrate. The K,, values using CDNB were lower for the field
populations compared to the F, progeny which were reared without any exposure
insecticides. The data indicate that the insects collected from the field were better
able to metabolise xenobiotics than their laboratory reared progeny wl-iich were
not exposed to any insecticides.International Program in the Chemical Sciences (UPPSALA, Sweden) and the Research board, University of Zimbabwe
Cytosolic glutathione s-transferases of ostrich liver.
No full textAn article with 14 pages.Chemicals consummumed by the ostrich are likely to be metabolised by liver detoxifying enzymes such as the cytosolic glutathione Stransferases
(GST). We have studied the affinity purified GST from male and female ostrich livers. 1-chloro-2, 4-dinitrobenzene
(CDNB) proved to be the best of several substrates tested to measme activity. Activity with this substrate was inhibited by
sulphobromoptgnalein and cibamon blue which are well established inhibitors for the m ammalian enzyme. A number of pesticides and
environmentai pollutants were also found to be strong inhibitors of the enzymes. Our data indicates that ostrich liver enzymes behave
similarly to the mammalian liver enzyme in terms of substrate requirements and inhibition characteristics.ZIMBANK, RK Financial from the University of Zimbabwe and International
Programs in the Chemical Sciences (Uppsaia,
Sweden
Lunar Drift Explains Lunar Eccentricity Rate
No full textHerein, we argue that the observed +38mm/yr secular Lunar drift from the Earth does ? to an admirable degree of agreement between theory and observations; explain the observed secular increase in the Lunar eccentricity. At present, the recession of the Moon from the Earth is not any more considered as an anomaly as this is believed to be well explained by conventional physics of Lunar-Earth tides. However, the same is not true when it come to the observed increase in the Lunar eccentricity which is considered to be an anomaly requiring an explanation as to what is the cause behind this phenomenon. We not only demonstrate an intimate connection between these two seemingly unrelated phenomenon, but show that the intimate relationship that we deduce fits so well with observations to a point that ? logic dictates that, the Lunar drift must surely be the cause of the secular increase in the Lunar eccentricity
Social Media Strategies for Dynamic Library Service Development
No full textPublished as part of the a volume in the Advances in Library and
Information Science (ALIS) Book Series.Like in any endeavor, adoption and use of social media requires planning. However, this is not the case
in Zimbabwe. To assess the situation, a study was conducted among different type of libraries in the
country. Purposive sampling technique was adopted. The objectives were to find out the libraries which
had social media strategic plans, and, among those which had none, to establish the extent to which social
media use policies and principles corresponded to the basic strategic plan model. Results indicated
that adopted tools include Facebook, Wikis, YouTube, Blogs, Twitter, Skype, Flicr, Ning, and LinkedIn.
Reasons for adoption included being trendy as well as to enhance the library?s efficiency, and goals
included to continuously avail information in a variety of formats to clients within a short space of time
and to effectively market library services. However, no library had a written social media strategic plan.
The principles and policies for using social media covered strategies for implementation, surveillance,
and monitoring of platforms for accountability