Should subsistence agriculture be supported as a strategy to address rural food insecurity?

At first glance South Africa’s black farming sector appears to contribute rather minimally to overall agricultural output in South Africa. However, despite the complexity involved in this sector and the often marginal conditions in which agriculture is practised it appears to be important to a large number of black households. Furthermore, the significance they attach to subsistence agriculture as means of supplementing household food supplies seems to heavily outweigh other reasons for engaging in agriculture. Some South African researchers have indicated the contribution subsistence production makes to household food security, despite the prevalent complexities and the low input nature of this production. Statistics South Africa’s Labour Force Survey data from 2001 to 2007 and a case study of subsistence farming in Limpopo Province are used to support the argument that, despite the complexity of this sector, the more than 4 million subsistence farmers, need and merit greater support. Such support should be based on the local context, build on and, where appropriate, improve existing local practices, while addressing various existing threats to this type of production. Recommendations are made as to what policy makers need to consider when considering how best to support subsistence production.subsistence production, Labour Force Survey, traditional crops, local agricultural practices, Consumer/Household Economics,

Lower-rim ferrocenyl substituted calixarenes: new electrochemical sensors for anions

New ferrocene substituted calix[4 and 5]arenes have been prepared and the crystal structure of a lower-rim substituted bis ferrocene calix[4]arene (7) has been elucidated. The respective ferrocene/ferrocenium redox-couples of compounds 6 (a calix[4]arene tetra ferrocene amide) and 8 (a calix[5]arene pentaferrocene amide) are shown to be significantly cathodically perturbed in the presence of anions by up to 160 mV in the presence of dihydrogen phosphate

Construction of the Views oN Infant Sleep (VNIS) Questionnaire

Parents' beliefs about infant sleep behaviour vary over time and across cultures. No validated instrument exists to understand parents' pre- and postnatal views on infant sleep behaviours, which may influence their caregiving decisions. The Views oN Infant Sleep Questionnaire (VNIS) will be a tool to assess parents' beliefs in order to facilitate tailored perinatal care, increase the reliability of postnatal self-report measures, allow for cross-cultural comparisons, and provide a baseline for researchers to use in longitudinal studies. We recruited an online sample of 971 female participants who were resident in the United Kingdom, at least 28 weeks pregnant, and at least 18 years of age. The initial questionnaire consisted of 31 questions about infant independence, night-waking, infant feeding, touch, and safety, and items were rated on a 5-point Likert scale. The item pool was reduced to 12 using principal component analysis and a structure was found for the three components “Closeness”, “Independence”, and “Night-waking”. Overall, these results suggest that the VNIS can provide a brief scale to measure different aspects of individuals' beliefs about infant sleep. In further research the VNIS needs to be validated with a confirmatory factor analysis in another sample, and to be tested as a cross-cultural instrument

Intercepted mosquitoes at New Zealand's ports of entry, 2001 to 2018: current status and future concerns

Mosquito vectors are extending their range via international travel and trade. Climate change makes New Zealand an increasingly suitable environment for less tropically adapted exotic mosquito vectors to become established. This shift will add a multiplier effect to existing risks of both the establishment of new species and of resident exotic species extending into new areas. We describe trends in the border interceptions of exotic mosquitoes and evaluate the role of imported goods as a pathway for these introductions. Ae. aegypti and Ae. albopictus, the two most commonly intercepted species, were only intercepted in Auckland. Used tyres and machinery were the main mode of entry for both species. The majority of Ae. albopictus were transported as larvae by sea, while most Ae. aegypti were transported as adults by air. Continuing introductions of these mosquitoes, mainly arriving via Japan or Australia, increase the risk of the local transmission of mosquito-borne diseases in New Zealand in general and in the Auckland region in particular. These findings reinforce the need for a high performing and adequately resourced national biosecurity system, particularly port surveillance and inspection. Recommended biosecurity improvements are described

Microwave-assisted and solvent-free peroxidative oxidation of 1-phenylethanol to acetophenone with a CuII–TEMPO catalytic system

Abstract The water-soluble copper(II) complex [Cu(H2R)(HL)]∙H2O (1) was prepared by reaction of copper(II) nitrate hydrate with (E)-2-(((1-hydroxynaphthalen-2-yl)methylene)amino) benzenesulfonic acid (H2L) and diethanolamine (H3R). It was characterized by IR and ESI-MS spectroscopies, elemental and X-ray crystal structural analyses. 1 shows a high catalytic activity for the solvent-free microwave (MW) assisted oxidation of 1-phenylethanol with tert-butylhydroperoxide, leading, in the presence of TEMPO, to yields up to 85% (TON = 850) in a remarkably short reaction time (15 min, with the corresponding TOF value of 3.40 × 103 h− 1) under low power (25 W) MW irradiation

High-harmonic generation from a confined atom

The order of high harmonics emitted by an atom in an intense laser field is limited by the so-called cutoff frequency. Solving the time-dependent Schr\"odinger equation, we show that this frequency can be increased considerably by a parabolic confining potential, if the confinement parameters are suitably chosen. Furthermore, due to confinement, the radiation intensity remains high throughout the extended emission range. All features observed can be explained with classical arguments.Comment: 4 pages(tex files), 4 figures(eps files); added references and comment

Baryogenesis, Electric Dipole Moments and Dark Matter in the MSSM

We study the implications for electroweak baryogenesis (EWB) within the minimal supersymmetric Standard Model (MSSM) of present and future searches for the permanent electric dipole moment (EDM) of the electron, for neutralino dark matter, and for supersymmetric particles at high energy colliders. We show that there exist regions of the MSSM parameter space that are consistent with both present two-loop EDM limits and the relic density and that allow for successful EWB through resonant chargino and neutralino processes at the electroweak phase transition. We also show that under certain conditions the lightest neutralino may be simultaneously responsible for both the baryon asymmetry and relic density. We give present constraints on chargino/neutralino-induced EWB implied by the flux of energetic neutrinos from the Sun, the prospective constraints from future neutrino telescopes and ton-sized direct detection experiments, and the possible signatures at the Large Hadron Collider and International Linear Collider.Comment: 32 pages, 10 figures; version to appear on JHE

Single hole dynamics in the t-J model on two- and three-leg ladders

The dynamics of a single hole in the t-J model on two- (2LL) and three- (3LL) leg ladders is studied using a recently developed quantum Monte Carlo algorithm. For the 2LL it is shown that in addition to the most pronounced features of the spectral function, well described by the limit of strong coupling along the rungs, a clear shadow band appears in the antibonding channel. Moreover, both the bonding band and its shadow have a finite quasiparticle (QP) weight in the thermodynamic limit. For strong coupling along the rungs of the 3LL, the low-energy spectrum in the antisymmetric channel is similar to a one-dimensional chain, whereas in the two symmetric channels it resembles the 2LL. The QP weight vanishes in the antisymmetric channel, but is finite in the symmetric one

Observation and Assignment of Silent and Higher Order Vibrations in the Infrared Transmission of C60 Crystals

We report the measurement of infrared transmission of large C60 single crystals. The spectra exhibit a very rich structure with over 180 vibrational absorptions visible in the 100 - 4000 cm-1 range. Many silent modes are observed to have become weakly IR-active. We also observe a large number of higher order combination modes. The temperature (77K - 300K) and pressure (0 - 25KBar) dependencies of these modes were measured and are presented. Careful analysis of the IR spectra in conjunction with Raman scattering data showing second order modes and neutron scattering data, allow the selection of the 46 vibrational modes C60. We are able to fit *all* of the first and second order data seen in the present IR spectra and the previously published Raman data (~300 lines total), using these 46 modes and their group theory allowed second order combinations.Comment: REVTEX v3.0 in LaTeX. 12 pages. 8 Figures by request. c60lon