Seasonal habitat selection by eland in arid savanna in southern Africa

The small scale seasonal habitat selection of eland in a semi-arid savanna was investigated. Linear discriminant functions and suitability index curves were calculated to differentiate between 314 m2 plots where eland were present and absent. Biological explanations were sought for the results. In winter eland relied on woody evergreen plants, while in summer they selected patches with good grass cover. Eland were independent of shelter and cover in both seasons. The ability of the discriminant functions to predict the presence and absence of eland was validated by classifying independent habitat samples. The functions were found to be reliable

Future Opportunities for IoT to Support People with Parkinson’s

Recent years have seen an explosion of internet of things (IoT) technologies being released to the market. There has also been an emerging interest in the potentials of IoT devices to support people with chronic health conditions. In this paper, we describe the results of engagements to scope the future potentials of IoT for supporting people with Parkinson’s. We ran a 2-day multi-disciplinary event with professionals with expertise in Parkinson’s and IoT, to explore the opportunities, challenges and benefits. We then ran 4 workshops, engaging 13 people with Parkinson’s and caregivers, to scope out the needs, values and desires that the community has for utilizing IoT to monitor their symptoms. This work contributes a set of considerations for future IoT solutions that might support people with Parkinson’s in better understanding their condition, through the provision of objective measurements that correspond to their, currently unmeasured, subjective experiences

Composition of woody species in a dynamic forest-woodland-savannah mosaic in Uganda: implications for conservation and management

Forest¿woodland¿savannah mosaics are a common feature in the East African landscape. For the conservation of the woody species that occur in such landscapes, the species patterns and the factors that maintain it need to be understood. We studied the woody species distribution in a forest¿woodland¿savannah mosaic in Budongo Forest Reserve, Uganda. The existing vegetation gradients were analyzed using data from a total of 591 plots of 400 or 500 m2 each. Remotely sensed data was used to explore current vegetation cover and the gradients there in for the whole area. A clear species gradient exists in the study area ranging from forest, where there is least disturbance, to wooded grassland, where frequent fire disturbance occurs. Most species are not limited to a specific part of the gradient although many show a maximum abundance at some point along the gradient. Fire and accessibility to the protected area were closely related to variation in species composition along the ordination axis with species like Cynometra alexandri and Uvariopsis congensis occurring at one end of the gradient and Combretum guenzi and Lonchocarpus laxiflorus at the other. The vegetation cover classes identified in the area differed in diversity, density and, especially, basal area. All vegetation cover classes, except open woodland, had indicator species. Diospyros abyssinica, Uvariopsis congensis, Holoptelea grandis and all Celtis species were the indicator species for the forest class, Terminalia velutina and Albizia grandbracteata for closed woodland, Grewia mollis and Combretum mole for very open woodland and Lonchocarpus laxiflorus, Grewia bicolor and Combretum guenzi for the wooded grassland class. Eleven of the species occurred in all cover classes and most of the species that occurred in more than one vegetation cover class showed peak abundance in a specific cover class. Species composition in the study area changes gradually from forest to savannah. Along the gradient, the cover classes are distinguishable in terms of species composition and vegetation structure. These classes are, however, interrelated in species composition. For conservation of the full range of the species within this East African landscape, the mosaic has to be managed as an integrated whole. Burning should be varied over the area with the forest not being burnt at all and the wooded grassland burnt regularly. The different vegetation types that occur between these two extremes should be maintained using a varied fire regim

The global burden of cancer attributable to risk factors, 2010–19: a systematic analysis for the Global Burden of Disease Study 2019

BACKGROUND: Understanding the magnitude of cancer burden attributable to potentially modifiable risk factors is crucial for development of effective prevention and mitigation strategies. We analysed results from the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2019 to inform cancer control planning efforts globally. METHODS: The GBD 2019 comparative risk assessment framework was used to estimate cancer burden attributable to behavioural, environmental and occupational, and metabolic risk factors. A total of 82 risk–outcome pairs were included on the basis of the World Cancer Research Fund criteria. Estimated cancer deaths and disability-adjusted life-years (DALYs) in 2019 and change in these measures between 2010 and 2019 are presented. FINDINGS: Globally, in 2019, the risk factors included in this analysis accounted for 4·45 million (95% uncertainty interval 4·01–4·94) deaths and 105 million (95·0–116) DALYs for both sexes combined, representing 44·4% (41·3–48·4) of all cancer deaths and 42·0% (39·1–45·6) of all DALYs. There were 2·88 million (2·60–3·18) risk-attributable cancer deaths in males (50·6% [47·8–54·1] of all male cancer deaths) and 1·58 million (1·36–1·84) risk-attributable cancer deaths in females (36·3% [32·5–41·3] of all female cancer deaths). The leading risk factors at the most detailed level globally for risk-attributable cancer deaths and DALYs in 2019 for both sexes combined were smoking, followed by alcohol use and high BMI. Risk-attributable cancer burden varied by world region and Socio-demographic Index (SDI), with smoking, unsafe sex, and alcohol use being the three leading risk factors for risk-attributable cancer DALYs in low SDI locations in 2019, whereas DALYs in high SDI locations mirrored the top three global risk factor rankings. From 2010 to 2019, global risk-attributable cancer deaths increased by 20·4% (12·6–28·4) and DALYs by 16·8% (8·8–25·0), with the greatest percentage increase in metabolic risks (34·7% [27·9–42·8] and 33·3% [25·8–42·0]). INTERPRETATION: The leading risk factors contributing to global cancer burden in 2019 were behavioural, whereas metabolic risk factors saw the largest increases between 2010 and 2019. Reducing exposure to these modifiable risk factors would decrease cancer mortality and DALY rates worldwide, and policies should be tailored appropriately to local cancer risk factor burden

The effect of animal size and adaptation on defoliation, selective defoliation, animal production and veld condition.

A conceptual model of the veld-herbivore relationship is presented. Large-sized, largely grazing animals feed relatively unselectively on abundant roughage. The carrying capacity of veld for them is high. They are low producers per animal, but high producers per ha. Per unit of metabolic mass they have a relatively minor effect on veld condition. Browsers and small-sized, largely grazing animals select strongly for concentrated food. The carrying capacity of veld for them is low. They are excellent converters per animal and per unit mass of intake. Their production per ha is low. One-animal-species models have been quantified readily. The complexity of two- or more-species models at present makes them prohibitively expensive and laborious to quantify. Two simplifications, one of which is readily testable, are proposed to circumvent the impasse.Keywords: animal production; browsers; carrying capacity; defoliation; grazing; intake; metabolic mass; modelling; models; production; selective defoliation; south africa; veld conditio

Are multi-paddock grazing systems economically justifiable?

The financial implications of few- and multi-paddock systems were modelled by a discounted cash flow analysis with the (discounted) present value as the dependent variable, and number of paddocks, farm run-down time, time horizon and discount rate as the independent variables. Present values were higher for few- than for multi-paddocks where rundown was slow, time horizon short and discount rate high. Present values were always higher for few- than for multi-paddocks when time horizon was short. At high discounts, present values over all modelled time horizons were higher for few- than multi-paddocks. Even if the conservation ideal of zero or low discounts obtains, there is little financial incentive for multi-paddocks for farmers with short planning horizons. Remedy of this by state aid and tax concessions has been tried. Success is not obvious, perhaps because subsidy has reduced farming costs and thereby prompted faster or greater resource depletion.Language: EnglishKeywords: conservation; Continuous grazing; discount rate; Discount rates; farming; grazing; grazing systems; modelling; planning; present value; Present values; Range deterioration; Rotational grazing; south afric

Evaluation of the wheel-point and step-point methods of veld condition assessment.

A number of aspects of a technique recently developed to assess the agro-ecological condition of veld were evaluated by 4 independent observers. Measuring the veld composition score yielded relatively repeatable results with a 95% confidence limit of (6,43 units for any single estimate which may range from 0 to 100 units. The step-point method yielded results on percentage veld composition and on veld composition score which did not differ in precision or in absolute amount from those obtained using the wheel-point apparatus. Adoption of the step point method in preference to the wheel-point method saves in equipment and manpower, and renders the technique usable by extension officers estimate of basal cover, and perhaps should not be used on uneven terrain or bushy veld. Using a circular-quadrat 3,5 cm in diameter yielded a more precise index of basal cover than did the standard method using a point-quadrat 1 mm in diameter. However, there are disadvantages in using the relatively large quadrat. Possible bias introduced into determining percentage species composition and composition score by using the nearest plant method were negligible.Keywords: basal cover; measuring; precision; quadrat; range; species composition; step-point method; technique; veld condition assessment; wheel-point metho

Management goals for wildlife reserves in grassveld and bushveld.

In South Africa most wildlife reserves are managed. Unambiguously stated goals are required if management is to be successful. The primary biological purpose of a reserve is proposed to be to maintain storehouses of dynamic genetic material. To perpetuate this dynamic resource, species-and communities-diversity must be managed to meet the minimum condition required to preserve soil. Land-units must be identified, and for each, a permissible range in vegetal cover and proportional species composition must be specified. Available data suggest that species-diversity is maximal where an agriculturally derived veld condition rating is fair to good. Fire and the number and proportions of different kinds of hoofed animals affect species-composition, vegetal cover and therefore veld condition, and therefore require control. A means of measuring the success of management is outlined.Keywords: condition; cover; fire; game reserves; genetic diversity; goals; management; management strategy; nature reserves; range; reserves; soil; south africa; species composition; species diversity; veld; veld condition; wildlif

Leaf silicification in grasses - a review.

Silica is absorbed from the soil by many grasses in an active or passive manner depending upon depending upon the species involved. It is carried upwards in the transpiration stream and deposited throughout the plant where it polymerizes to form amorphous silica gel. Deposition appears to be a passive process but some active mechanism may be involved. Deposition follows a set sequence and may be initiated before leaf expansion. Silica benefits most plants but may have adverse effects upon herbivores ingesting this plant silica. A number of possible roles have been suggested for silica deposition in plants such as the "light window" hypothesis or as a defence against large herbivores and these are discussed in the light of the available evidence. It is concluded that leaf silicification evolved in response to invertebrate herbivory and is primarily aimed at reducing tissue loss to these herbivores.Keywords: adaptive significance; benefits; deposition; distribution; functions; grass; grasses; herbivory; hypothesis; large herbivores; leaf; leaves; process; role; silica; silicification; transpiration; uptak