Willingness to establish private forest plantation among dwellers in some selected Local Government Area of Osun State, Nigeria

This study was carried out to investigate the willingness to establish private forest plantations among dwellers in Ife North, Ede South and Osogbo Local Government Areas of Osun State. One hundred and seventeen (117) questionnaires were administered randomly to selected respondents from nine (9) selected communities in the study areas, while ninety-three (93) copies of questionnaire were retrieved. Multi-stage sampling technique was used to select respondents from the study area. The willingness of the respondents to private forest plantation establishment showed that 64.5% of the respondents agreed on establishment of private forest plantation. Chi-square analysis indicated that a significant relationship exist between respondents’ sex, level of education, source of labour and secondary occupation on willingness to establish private forest plantation. Many of the dwellers faced some problems which influenced their willingness in establishing private forest plantations such as poor extension service, land tenure system, small land holding, non-availability of seed/seedlings, lack of technical know-how, Government policies, trees casting shadow on crops, etc. More dwellers can be encouraged in willingness to participate in private forest plantation through extension service to farmers, government institutions’ involvement at various levels of activities that will encourage individuals and organizations to establish private forest plantations. Government policies on land tenure system should be reviewed to encourage individual or private organisations to invest and actively participate more in forest plantation establishment.Keywords: Willingness, Private Forests, Plantation Establishmen

A geometric discretisation scheme applied to the Abelian Chern-Simons theory

We give a detailed general description of a recent geometrical discretisation scheme and illustrate, by explicit numerical calculation, the scheme's ability to capture topological features. The scheme is applied to the Abelian Chern-Simons theory and leads, after a necessary field doubling, to an expression for the discrete partition function in terms of untwisted Reidemeister torsion and of various triangulation dependent factors. The discrete partition function is evaluated computationally for various triangulations of $S^3$ and of lens spaces. The results confirm that the discretisation scheme is triangulation independent and coincides with the continuum partition functionComment: 27 pages, 5 figures, 6 tables. in late

Large deviations for many Brownian bridges with symmetrised initial-terminal condition

Consider a large system of $N$ Brownian motions in $\mathbb{R}^d$ with some non-degenerate initial measure on some fixed time interval $[0,\beta]$ with symmetrised initial-terminal condition. That is, for any $i$, the terminal location of the $i$-th motion is affixed to the initial point of the $\sigma(i)$-th motion, where $\sigma$ is a uniformly distributed random permutation of $1,...,N$. Such systems play an important role in quantum physics in the description of Boson systems at positive temperature $1/\beta$. In this paper, we describe the large-N behaviour of the empirical path measure (the mean of the Dirac measures in the $N$ paths) and of the mean of the normalised occupation measures of the $N$ motions in terms of large deviations principles. The rate functions are given as variational formulas involving certain entropies and Fenchel-Legendre transforms. Consequences are drawn for asymptotic independence statements and laws of large numbers. In the special case related to quantum physics, our rate function for the occupation measures turns out to be equal to the well-known Donsker-Varadhan rate function for the occupation measures of one motion in the limit of diverging time. This enables us to prove a simple formula for the large-N asymptotic of the symmetrised trace of ${\rm e}^{-\beta \mathcal{H}_N}$, where $\mathcal{H}_N$ is an $N$-particle Hamilton operator in a trap

Investigating the Potential for Unanticipated Consequences of Teaching the Tentative Nature of Science

If you are reading information supportive of climate science, you may well read that climate science is “settled science.” If you are reading something from a climate science skeptic, you may well read that climate science is “just a theory.” Given that the science education community strongly supports teaching the tentative nature of scientific knowledge, one might think that the skeptic has a legitimate argument. Experts will quickly object that such a deduction is quite wrong, and we agree. Nevertheless, we can’t help but wonder to what extent teaching the tentative nature of scientific knowledge might undermine confidence in science, especially for those who have not grasped important epistemological nuances. Our paper reports the findings from an initial exploration of this possibility

Quantum-mechanical tunnelling and the renormalization group

We explore the applicability of the exact renormalization group to the study of tunnelling phenomena. We investigate quantum-mechanical systems whose energy eigenstates are affected significantly by tunnelling through a barrier in the potential. Within the approximation of the derivative expansion, we find that the exact renormalization group predicts the correct qualitative behaviour for the lowest energy eigenvalues. However, quantitative accuracy is achieved only for potentials with small barriers. For large barriers, the use of alternative methods, such as saddle-point expansions, can provide quantitative accuracy.Comment: 9 pages, 5 figures, to appear in Phys. Lett.

Duality properties of indicatrices of knots

The bridge index and superbridge index of a knot are important invariants in knot theory. We define the bridge map of a knot conformation, which is closely related to these two invariants, and interpret it in terms of the tangent indicatrix of the knot conformation. Using the concepts of dual and derivative curves of spherical curves as introduced by Arnold, we show that the graph of the bridge map is the union of the binormal indicatrix, its antipodal curve, and some number of great circles. Similarly, we define the inflection map of a knot conformation, interpret it in terms of the binormal indicatrix, and express its graph in terms of the tangent indicatrix. This duality relationship is also studied for another dual pair of curves, the normal and Darboux indicatrices of a knot conformation. The analogous concepts are defined and results are derived for stick knots.Comment: 22 pages, 9 figure

Genetic Interactions between Doublecortin and Doublecortin-like Kinase in Neuronal Migration and Axon Outgrowth

SummaryAlthough mutations in the human doublecortin gene (DCX) cause profound defects in cortical neuronal migration, a genetic deletion of Dcx in mice produces a milder defect. A second locus, doublecortin-like kinase (Dclk), encodes a protein with similar “doublecortin domains” and microtubule stabilization properties that may compensate for Dcx. Here, we generate a mouse with a Dclk mutation that causes no obvious migrational abnormalities but show that mice mutant for both Dcx and Dclk demonstrate perinatal lethality, disorganized neocortical layering, and profound hippocampal cytoarchitectural disorganization. Surprisingly, Dcx−/y;Dclk−/− mutants have widespread axonal defects, affecting the corpus callosum, anterior commissure, subcortical fiber tracts, and internal capsule. Dcx/Dclk-deficient dissociated neurons show abnormal axon outgrowth and dendritic structure, with defects in axonal transport of synaptic vesicle proteins. Dcx and Dclk may directly or indirectly regulate microtubule-based vesicle transport, a process critical to both neuronal migration and axon outgrowth

Mental health in UK Biobank: development, implementation and results from an online questionnaire completed by 157 366 participants

Background UK Biobank is a well-characterised cohort of over 500 000 participants that offers unique opportunities to investigate multiple diseases and risk factors. Aims An online mental health questionnaire completed by UK Biobank participants was expected to expand the potential for research into mental disorders. Method An expert working group designed the questionnaire, using established measures where possible, and consulting with a patient group regarding acceptability. Case definitions were defined using operational criteria for lifetime depression, mania, anxiety disorder, psychotic-like experiences and self-harm, as well as current post-traumatic stress and alcohol use disorders. Results 157 366 completed online questionnaires were available by August 2017. Comparison of self-reported diagnosed mental disorder with a contemporary study shows a similar prevalence, despite respondents being of higher average socioeconomic status than the general population across a range of indicators. Thirty-five per cent (55 750) of participants had at least one defined syndrome, of which lifetime depression was the most common at 24% (37 434). There was extensive comorbidity among the syndromes. Mental disorders were associated with high neuroticism score, adverse life events and long-term illness; addiction and bipolar affective disorder in particular were associated with measures of deprivation. Conclusions The questionnaire represents a very large mental health survey in itself, and the results presented here show high face validity, although caution is needed owing to selection bias. Built into UK Biobank, these data intersect with other health data to offer unparalleled potential for crosscutting biomedical research involving mental health

Huge metastability in high-T_c superconductors induced by parallel magnetic field

We present a study of the temperature-magnetic field phase diagram of homogeneous and inhomogeneous superconductivity in the case of a quasi-two-dimensional superconductor with an extended saddle point in the energy dispersion under a parallel magnetic field. At low temperature, a huge metastability region appears, limited above by a steep superheating critical field (H_sh) and below by a strongly reentrant supercooling field (H_sc). We show that the Pauli limit (H_p) for the upper critical magnetic field is strongly enhanced due to the presence of the Van Hove singularity in the density of states. The formation of a non-uniform superconducting state is predicted to be very unlikely.Comment: 5 pages, 2 figures; to appear in Phys. Rev.

Effects of varenicline and cognitive bias modification on neural response to smoking-related cues:Study protocol for a randomized controlled study

BACKGROUND: Smoking-related cues can trigger drug-seeking behaviors, and computer-based interventions that reduce cognitive biases towards such cues may be efficacious and cost-effective cessation aids. In order to optimize such interventions, there needs to be better understanding of the mechanisms underlying the effects of cognitive bias modification (CBM). Here we present a protocol for an investigation of the neural effects of CBM and varenicline in non-quitting daily smokers. METHODS/DESIGN: We will recruit 72 daily smokers who report smoking at least 10 manufactured cigarettes or 15 roll-ups per day and who smoke within one hour of waking. Participants will attend two sessions approximately one week apart. At the first session participants will be screened for eligibility and randomized to receive either varenicline or a placebo over a seven-day period. On the final drug-taking day (day seven) participants will attend a second session and be further randomized to one of three CBM conditions (training towards smoking cues, training away from smoking cues, or control training). Participants will then undergo a functional magnetic resonance imaging scan during which they will view smoking-related pictorial cues. Primary outcome measures are changes in cognitive bias as measured by the visual dot-probe task, and neural responses to smoking-related cues. Secondary outcome measures will be cognitive bias as measured by a transfer task (modified Stroop test of smoking-related cognitive bias) and subjective mood and cigarette craving. DISCUSSION: This study will add to the relatively small literature examining the effects of CBM in addictions. It will address novel questions regarding the neural effects of CBM. It will also investigate whether varenicline treatment alters neural response to smoking-related cues. These findings will inform future research that can develop behavioral treatments that target relapse prevention. TRIAL REGISTRATION: Registered with Current Controlled Trials: ISRCTN65690030. Registered on 30 January 2014