Analysis of seed yam varieties, sources and quantity demanded by farmers in major yam producing districts in Ghana

The study analysed the varieties, sources and quantities of seed yam demanded by farmers for cultivation in order to inform policies aimed at ensuring adequate supply of quality seed yam of desirable varieties at an affordable price to boost yam productivity for improved income and livelihoods. A structured questionnaire was administered to 380 randomly selected yam farmers in three major yam producing districts in Ghana in 2015. The data analysis was done using STATA statistical software. The study identified Pona/Punjo, Lariboko, Asana, Afebetuye, Dente, Olondo and Kparinjo as the yam varieties mainly cultivated by farmers in a reducing order with high market demands by consumers. Own production remains the major source of seed yam for farmers. The estimated monetary value of quantity of seed yam used by farmers for cultivation in 2014 farming season was GH¢ 198, 552,841.0 (USD 51,706,469.0) in the study locations. About GH¢ 5,679,979.0 (USD 1,479,161.2) worth of quantities of seed yam was obtained from the market and other sources. The results demonstrate the existence of market potential for commercial seed yam production and supply in Ghana. Commercial seed yam certification system and yam breeding activities should target the identified yam varieties

High-powEr Phosphorous-based DFB Lasers for Cold Atom Systems (HELCATS)

No abstract available

Combining Effects and Coeffects via Grading

This is the author accepted manuscript. It is currently under an indefinite embargo pending publication by the Association for Computing Machinery.$\textit{Effects}$ and $\textit{coeffects}$ are two general, complementary aspects of program behaviour. They roughly correspond to computations which change the execution context (effects) versus computations which make demands on the context (coeffects). Effectful features include partiality, non-determinism, input-output, state, and exceptions. Coeffectful features include resource demands, variable access, notions of linearity, and data input requirements. The effectful or coeffectful behaviour of a program can be captured and described via type-based analyses, with fine grained information provided by monoidal effect annotations and semiring coeffects. Various recent work has proposed models for such typed calculi in terms of $\textit{graded (strong) monads}$ for effects and $\textit{graded (monoidal) comonads}$ for coeffects. Effects and coeffects have been studied separately so far, but in practice many computations are both effectful and coeffectful, e.g., possibly throwing exceptions but with resource requirements. To remedy this, we introduce a new general calculus with a combined $\textit{effect-coeffect system}$. This can describe both the $\textit{changes}$ and $\textit{requirements}$ that a program has on its context, as well as interactions between these effectful and coeffectful features of computation. The effect-coeffect system has a denotational model in terms of effect-graded monads and coeffect-graded comonads where interaction is expressed via the novel concept of $\textit{graded distributive laws}$. This graded semantics unifies the syntactic type theory with the denotational model. We show that our calculus can be instantiated to describe in a natural way various different kinds of interaction between a program and its evaluation context.Orchard was supported by EPSRC grant EP/M026124/1 and EP/K011715/1 (whilst previously at Imperial College London), Katsumata by JSPS KAKENHI grant JP15K00014, Uustalu by Estonian Min. of Educ. and Res. grant IUT33-13 and Estonian Sci. Found. grant 9475. Gaboardi’s work was done in part while at the University of Dundee, UK supported by EPSRC grant EP/M022358/1

Model combustion-generated particulate matter containing persistent free radicals redox cycle to produce reactive oxygen species

Particulate matter (PM) is emitted during thermal decomposition of waste. During this process, aromatic compounds chemisorb to the surface of metal-oxide-containing PM, forming a surface-stabilized environmentally persistent free radical (EPFR). We hypothesized that EPFR-containing PM redox cycle to produce ROS and that this redox cycle is maintained in biological environments. To test our hypothesis, we incubated model EPFRs with the fluorescent probe dihydrorhodamine (DHR). Marked increases in DHR fluorescence were observed. Using a more specific assay, hydroxyl radicals ( •OH) were also detected, and their level was further increased by cotreatment with thiols or ascorbic acid (AA), known components of epithelial lining fluid. Next, we incubated our model EPFR in bronchoalveolar lavage fluid (BALF) or serum. Detection of EPFRs and •OH verified that PM generate ROS in biological fluids. Moreover, incubation of pulmonary epithelial cells with EPFR-containing PM increased •OH levels compared to those in PM lacking EPFRs. Finally, measurements of oxidant injury in neonatal rats exposed to EPFRs by inhalation suggested that EPFRs induce an oxidant injury within the lung lining fluid and that the lung responds by increasing antioxidant levels. In summary, our EPFR-containing PM redox cycle to produce ROS, and these ROS are maintained in biological fluids and environments. Moreover, these ROS may modulate toxic responses of PM in biological tissues such as the lung. © 2013 American Chemical Society

Catechol-TiO₂ hybrids for photocatalytic H₂ production and photocathode assembly

Visible-light driven H₂ evolution in water is achieved using catechol-photosensitised TiO₂ nanoparticles with a molecular nickel catalyst. Layer-by-layer immobilisation of catechol-TiO₂ onto tin-doped indium oxide electrodes generates photocathodic currents in the presence of an electron acceptor. This approach represents a new strategy for controlling photocurrent direction in dye-sensitised photoelectrochemical applications.We gratefully acknowledge financial support by the EPSRC and World Premier International Research Center Initiative, MEXT, Japan

Low back pain status in elite and semi-elite Australian football codes: a cross-sectional survey of football (soccer), Australian rules, rugby league, rugby union and non-athletic controls

<p>Abstract</p> <p>Background</p> <p>Our understanding of the effects of football code participation on low back pain (LBP) is limited. It is unclear whether LBP is more prevalent in athletic populations or differs between levels of competition. Thus it was the aim of this study to document and compare the prevalence, intensity, quality and frequency of LBP between elite and semi-elite male Australian football code participants and a non-athletic group.</p> <p>Methods</p> <p>A cross-sectional survey of elite and semi-elite male Australian football code participants and a non-athletic group was performed. Participants completed a self-reported questionnaire incorporating the Quadruple Visual Analogue Scale (QVAS) and McGill Pain Questionnaire (short form) (MPQ-SF), along with additional questions adapted from an Australian epidemiological study. Respondents were 271 elite players (mean age 23.3, range 17–39), 360 semi-elite players (mean age 23.8, range 16–46) and 148 non-athletic controls (mean age 23.9, range 18–39).</p> <p>Results</p> <p>Groups were matched for age (p = 0.42) and experienced the same age of first onset LBP (p = 0.40). A significant linear increase in LBP from the non-athletic group, to the semi-elite and elite groups for the QVAS and the MPQ-SF was evident (p < 0.001). Elite subjects were more likely to experience more frequent (daily or weekly OR 1.77, 95% CI 1.29–2.42) and severe LBP (discomforting and greater OR 1.75, 95% CI 1.29–2.38).</p> <p>Conclusion</p> <p>Foolers in Australia have significantly more severe and frequent LBP than a non-athletic group and this escalates with level of competition.</p