Nectar secretion dynamics of : A melliferous species of dry land ecosystems.

Nectar is used as raw material for the production of honey and as significant reward in the relationship between bees and plants during pollination. Therefore, it is important to investigate its abundance, dynamics and associated governing factors. Weather conditions are known to influence nectar production, and predicted climate changes may be responsible for future declining in total yield from beekeeping activities.

Vulnerability in speed of visuomotor ability.

The aim of this report is to illustrate the utility of neurocognitive testing as an investigative method to establish the presence of persistent effects of concussive brain injury amongst players of a contact sport with high risk of such injury. The report reviews the outcomes of three previously published neuropsychological studies on South African Rugby Union (hereafter 'rugby') from school through to the national adult level. The diagnostic utility of differential effects per se, as well as differential practice effects on visuomotor function, as a means of distinguishing poorer neurocognitive outcome for rugby versus demographically equivalent noncontact sports players, is described.

Practice effects reveal visuomotor vulnerability in school and university rugby players.

This article reports on three pre- versus post-season prospective studies in which male university and high school contact sport players predominantly of Rugby Union (hereafter rugby) were compared with age, education, and IQ equivalent non-contact sport controls on the ImPACT (Immediate Postconcussion Assessment and Cognitive Testing) test. All analyses revealed a relative absence of practice effects on the Visual Motor Speed (VMS) composite for contact sport groups compared with controls. The VMS data for rugby players from each study were pooled and subjected to additional analysis (Rugby, n = 145; Controls, n = 106).

An experiment on comb orientation by honey bees (Hymenoptera: Apidae) in traditional hives.

The orientation of combs in traditional beehives is extremely important for obtaining a marketable honey product. However, the factors that could determine comb orientation in traditional hives and the possibilities of inducing honey bees, Apis mellifera (L.), to construct more desirable combs have not been investigated.

Lime pretreatment of sugar beet pulp and evaluation of synergy between ArfA, ManA and XynA from Clostridium cellulovorans on the pretreated substrate.

Sugar beet pulp (SBP) is a waste product from the sugar beet industry and could be used as a potential biomass feedstock for second generation biofuel technology. Pretreatment of SBP with 'slake lime' (calcium hydroxide) was investigated using a 2(3) factorial design and the factors examined included lime loading, temperature and time. The pretreatment was evaluated for its ability to enhance enzymatic degradation using a combination of three hemicellulases, namely ArfA (an arabinofuranosidase), ManA (an endo-mannanase) and XynA (an endo-xylanase) from C.

Reproductive biology of the Cape honeybee: a critique of Beekman et al.

Laying workers of the Cape honeybee parthenogenetically produce female offspring, whereas queens typically produce males. Beekman et al. confirm this observation, which has repeatedly been reported over the last 100 years including the notion that natural selection should favor asexual reproduction in Apis mellifera capensis.

The pheromones of laying workers in two honeybee sister species: Apis cerana and Apis mellifera.

When a honeybee colony loses its queen, workers activate their ovaries and begin to lay eggs. This is accompanied by a shift in their pheromonal bouquet, which becomes more queen like. Workers of the Asian hive bee Apis cerana show unusually high levels of ovary activation and this can be interpreted as evidence for a recent evolutionary arms race between queens and workers over worker reproduction in this species.

Economics of comb wax salvage by the red dwarf honeybee, Apis florea.

Colonies of Apis florea, which only abscond a short distance, usually return to salvage old nest wax; but, those colonies, and all other honeybee species which go considerably further, do not. Wax salvage would clearly be counter-productive unless the energy input/energy yield threshold was a profitable one. There are two possible trade-offs in this scenario, the trade-off between the energy expended to recover the wax (recovering hypothesis) as against that of replacing the wax by new secretion (replacing hypothesis).

Responses of queenright and queenless workers of Apis cerana to 9-keto-2(E)-decenoic acid, a pheromonal constituent of the mandibular gland.

In dequeened honeybee colonies ovarian activation occurs in some workers, and the pheromonal bouquets of these laying workers become more queen-like. In the Asiatic honeybee, Apis cerana, we compared the amount of 9-keto-2(E)-decenoic acid (9-ODA), a mandibular gland pheromone component, between non-laying workers from queenright colonies and laying workers from queenless colonies, and further, applied synthetic 9-ODA to workers to determine whether they discriminate workers with activated ovaries based on the level of this compound. Levels of 9-ODA were higher in laying workers from dequeened colonies than in non-laying workers from queenright colonies.

Comb construction in mixed-species colonies of honeybees, Apis cerana and Apis mellifera.

Comb building in mixed-species colonies of Apis cerana and Apis mellifera was studied. Two types of cell-size foundation were made from the waxes of these species and inserted into mixed colonies headed either by an A. cerana or an A.

Computerized neuropsychological profiles of South African versus US athletes: a basis for commentary on cross-cultural norming issues in the sports concussion arena.

Computerized programs are widely used as part of the overall medical management of concussion in order to monitor recovery and facilitate safe return-to-play decisions. Typically, neurocognitive profiles of concussed athletes are compared with baseline and/or normative data in the absence of baseline scores. However, the cultural equivalence of performance on neuropsychological tests cannot be assumed and has not been sufficiently researched.

Thermoregulation in mixed-species colonies of honeybees (Apis cerana and Apis mellifera).

Apis cerana and Apis mellifera normally display different strategies in cooling hive temperature, raising the question whether they would coordinate their efforts in to achieve stable thermoregulation in mixed colonies. The results show that the normal temperatures in the brood area in mixed colonies are more similar to those of pure A. cerana colonies than pure A.

Sun angle time windows for absconding by the dwarf honeybee, Apis florea.

In Asia, the red dwarf honeybee, Apis florea, is notorious for its absconding habit. Interestingly, such colonies show a bimodal frequency distribution about a noonday lull throughout the year. Because slight errors in reading the relative position of the sun near its zenith results in very large orientation errors in the waggle dances of other honeybees in the tropics, we postulated that the frequency distribution of absconding in the red dwarf honeybee relative to local clock time could be explained in similar fashion.

Interspecific utilisation of wax in comb building by honeybees.

Beeswaxes of honeybee species share some homologous neutral lipids; but species-specific differences remain. We analysed behavioural variation for wax choice in honeybees, calculated the Euclidean distances for different beeswaxes and assessed the relationship of Euclidean distances to wax choice. We tested the beeswaxes of Apis mellifera capensis, Apis florea, Apis cerana and Apis dorsata and the plant and mineral waxes Japan, candelilla, bayberry and ozokerite as sheets placed in colonies of A.

The comparative incidence of reported concussions presenting for follow-up management in South African Rugby Union.

Objective: The objective of this study was to compare the seasonal concussion incidence for school, university, club and provincial level Rugby Union players in South Africa.

Design: The study presents a retrospective statistical analysis of the number of reported concussions documented annually for groups of Rugby Union players as a proportion of those who received preseason neurocognitive assessment.

Setting: Between 2002 and 2006, concussion management programs using computerized neuropsychological assessment were implemented for clinical and research purposes by psychologists in selected South African institutions involved in Rugby Union from school through to the professional level.

Neurocognitive vulnerability amongst university rugby players versus noncontact sport controls.

University rugby players were compared with IQ-equivalent noncontact sports controls on memory and attentional tasks at the pre- and postseason intervals. Results revealed significant lowering for rugby players relative to controls at the postseason interval for attentional tasks with a speeded visuomotor component (ImPACT Visual Motor Speed; Trail Making Test, TMT, A and B). There was a practice effect for controls only between the pre- and postseason intervals for attentional tasks that commonly reveal improvements after a long retest interval (TMT A and B; Digits Backwards).

Compromised visuomotor processing speed in players of Rugby Union from school through to the national adult level.

The aim of this study was to investigate the residual effects of concussion amongst players of Rugby Union from school through to the national adult level, with pre-season testing on tests of visuomotor processing speed (Digit Symbol; Trail Making Test A and B). Comparison groups included 124 male rugby players versus 102 non-contact sport controls; 71 forward versus 53 backline players. Across groups there was equivalence for age, education, estimated IQ, and hand motor dexterity.

Self assessment in insects: honeybee queens know their own strength.

Contests mediate access to reproductive opportunities in almost all species of animals. An important aspect of the evolution of contests is the reduction of the costs incurred during intra-specific encounters to a minimum. However, escalated fights are commonly lethal in some species like the honeybee, Apis mellifera.

The role of insight into and beliefs about medicines of hypertensive patients.

Objectives: One aim of this study was to determine the level of knowledge and understanding of selected individuals about hypertension, as well as their beliefs and perceptions about medicines. The other purpose was to determine the medicines information provision system that these participants were exposed to.

Methods: Participants filled in the Beliefs about Medicines questionnaire and one-on-one interviews were conducted.

Rare royal families in honeybees, Apis mellifera.

The queen is the dominant female in the honeybee colony, Apis mellifera, and controls reproduction. Queen larvae are selected by the workers and are fed a special diet (royal jelly), which determines caste. Because queens mate with many males a large number of subfamilies coexist in the colony.

A cross-cultural study with culture fair normative indications on WAIS-III Digit Symbol-Incidental Learning.

The WAIS-III Digit Symbol-Incidental Learning optional procedure, including Pairing and Free Recall, was administered to a southern African sample (N=68, age range 19-30), which was stratified for ethnicity in association with language of origin (white English first language versus black African first language), educational level (Grade 12 and Graduate), and quality of education (advantaged and disadvantaged). ('African language' is the term used to denote the indigenous languages of black populations in southern Africa). Results yielded no significant differences for ethnicity/language of origin, level or quality of education, indicating that Digit Symbol-Incidental Learning may be a relatively culture independent task with utility as a neuropsychological screening instrument.

Cross-cultural effects on IQ test performance: a review and preliminary normative indications on WAIS-III test performance.

This article presents a review of cross-cultural influences on Wechsler IQ tests, together with a preliminary investigation into WAIS-III test performance (English administration) for a southern African sample (age range 19-30) stratified for white English first language and black African first language, level and quality of education. ('African language' is the term used to denote the indigenous languages of black populations in southern Africa). A two-way ANOVA revealed highly significant effects for both level and quality of education within the black African first language group.

Genetic variation in natural honeybee populations, Apis mellifera capensis.

Genetic variation in honeybee, Apis mellifera, populations can be considerably influenced by breeding and commercial introductions, especially in areas with abundant beekeeping. However, in southern Africa apiculture is based on the capture of wild swarms, and queen rearing is virtually absent. Moreover, the introduction of European subspecies constantly failed in the Cape region.