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Objectives/hypothesis: To determine the mode of inheritance of familial nonsyndromic Mondini dysplasia.Study Design: Correlative clinical genetic analysis of a single kindred.Methods: Clinical history, physical examination, audiologic analysis, computed tomography of the temporal bones, and cytogenetic analysis.Results: The male proband, three affected sisters, and an affected brother are offspring of unaffected parents. The mother and an unaffected brother have audiologic findings suggestive of heterozygous carrier status for a recessive hearing loss gene.Conclusions: Pedigree analysis indicates autosomal recessive inheritance in this family. The observed inheritance and clinical, audiologic, and radiologic findings are different from those previously described for another family with nonsyndromic Mondini dysplasia. The phenotype in this study family therefore represents a distinct subtype, indicating clinical and genetic heterogeneity of this disorder. This information should facilitate future molecular linkage analyses and genetic counselling of patients with inner ear malformations. [ABSTRACT FROM AUTHOR]

The article focuses on the systemic insecticide fipronil and those which belong to the neonicotinoid family. The increasing global dependance on the prophylactic use of these potent neurotoxic systemic insecticides has raised concerns about their effects on biodiversity and ecosystem services provided by a wide range of affected species and environments.

Since their discovery in the late 1980s, neonicotinoid pesticides have become the most widely used class of insecticides worldwide, with large-scale applications ranging from plant protection (crops, vegetables, fruits), veterinary products, and biocides to invertebrate pest control in fish farming. In this review, we address the phenyl-pyrazole fipronil together with neonicotinoids because of similarities in their toxicity, physicochemical profiles, and presence in the environment. Neonicotinoids and fipronil currently account for approximately one third of the world insecticide market; the annual world production of the archetype neonicotinoid, imidacloprid, was estimated to be ca. 20,000 tonnes active substance in 2010. There were several reasons for the initial success of neonicotinoids and fipronil: (1) there was no known pesticide resistance in target pests, mainly because of their recent development, (2) their physicochemical properties included many advantages over previous generations of insecticides (i.e., organophosphates, carbamates, pyrethroids, etc.), and (3) they shared an assumed reduced operator and consumer risk. Due to their systemic nature, they are taken up by the roots or leaves and translocated to all parts of the plant, which, in turn, makes them effectively toxic to herbivorous insects. The toxicity persists for a variable period of time-depending on the plant, its growth stage, and the amount of pesticide applied. A wide variety of applications are available, including the most common prophylactic non-Good Agricultural Practices (GAP) application by seed coating. As a result of their extensive use and physicochemical properties, these substances can be found in all environmental compartments including soil, water, and air. Neonicotinoids and fipronil operate by disrupting neural transmission in the central nervous system of invertebrates. Neonicotinoids mimic the action of neurotransmitters, while fipronil inhibits neuronal receptors. In doing so, they continuously stimulate neurons leading ultimately to death of target invertebrates. Like virtually all insecticides, they can also have lethal and sublethal impacts on non-target organisms, including insect predators and vertebrates. Furthermore, a range of synergistic effects with other stressors have been documented. Here, we review extensively their metabolic pathways, showing how they form both compound-specific and common metabolites which can themselves be toxic. These may result in prolonged toxicity. Considering their wide commercial expansion, mode of action, the systemic properties in plants, persistence and environmental fate, coupled with limited information about the toxicity profiles of these compounds and their metabolites, neonicotinoids and fipronil may entail significant risks to the environment. A global evaluation of the potential collateral effects of their use is therefore timely. The present paper and subsequent chapters in this review of the global literature explore these risks and show a growing body of evidence that persistent, low concentrations of these insecticides pose serious risks of undesirable environmental impacts. [ABSTRACT FROM AUTHOR]

We assessed the state of knowledge regarding the effects of large-scale pollution with neonicotinoid insecticides and fipronil on non-target invertebrate species of terrestrial, freshwater and marine environments. A large section of the assessment is dedicated to the state of knowledge on sublethal effects on honeybees ( Apis mellifera) because this important pollinator is the most studied non-target invertebrate species. Lepidoptera (butterflies and moths), Lumbricidae (earthworms), Apoidae sensu lato (bumblebees, solitary bees) and the section 'other invertebrates' review available studies on the other terrestrial species. The sections on freshwater and marine species are rather short as little is known so far about the impact of neonicotinoid insecticides and fipronil on the diverse invertebrate fauna of these widely exposed habitats. For terrestrial and aquatic invertebrate species, the known effects of neonicotinoid pesticides and fipronil are described ranging from organismal toxicology and behavioural effects to population-level effects. For earthworms, freshwater and marine species, the relation of findings to regulatory risk assessment is described. Neonicotinoid insecticides exhibit very high toxicity to a wide range of invertebrates, particularly insects, and field-realistic exposure is likely to result in both lethal and a broad range of important sublethal impacts. There is a major knowledge gap regarding impacts on the grand majority of invertebrates, many of which perform essential roles enabling healthy ecosystem functioning. The data on the few non-target species on which field tests have been performed are limited by major flaws in the outdated test protocols. Despite large knowledge gaps and uncertainties, enough knowledge exists to conclude that existing levels of pollution with neonicotinoids and fipronil resulting from presently authorized uses frequently exceed the lowest observed adverse effect concentrations and are thus likely to have large-scale and wide ranging negative biological and ecological impacts on a wide range of non-target invertebrates in terrestrial, aquatic, marine and benthic habitats. [ABSTRACT FROM AUTHOR]

Huddling is a behavioural energy conservation mechanism that is widely used by many small endotherms at low ambient temperatures. Huddling has many benefits, including decreasing the metabolic cost of maintaining body temperature (Tb), reducing the amount of heat lost to the environment, and increasing the local temperature of the nest. To test the effects of huddling on Tb, 10 rock hyrax, Procavia capensis, were housed in outside cages in four groups, varying from one to four individuals. iButtons® were surgically implanted into each rock hyrax to record their Tb every 15 min from August to November. Despite considerable variations in ambient temperatures, the rock hyrax were found to display some degree of heterothermy by varying their mean Tb from 36.70 to 37.72°C (n = 10) but not allowing it to drop below 33.60°C or rise above 39.67°C. Contrary to what was predicted, rock hyrax did not display any significant effects of huddling on Tb, irrespective of group size. [ABSTRACT FROM AUTHOR]

The leopard tortoise (Stigmochelys pardalis) is the largest of southern Africa's 13 tortoise species, and occurs in a variety of habitats from arid and semi-arid areas to mesic grassveld, savanna and bushveld. Seasonal activity patterns of S. pardalis were investigated as a function of rainfall, sex, time of day, temperature and time after sunrise on farmland in the semi-arid Nama-Karoo, South Africa. We predicted that because of seasonal rainfall, and subsequent increase in the food available, activity patterns of leopard tortoises would vary greatly among seasons, but that the primary constraint on activity levels within a season would be ambient temperature. Type of activity, time of day that the activity was performed, and the frequency that each activity was performed, differed among seasons. There was no overall seasonal difference in the level of activity with sex, but in certain seasons and with regard to specific activities, there were significant differences between the sexes. Diel activity was primarily bimodal in summer and autumn, and unimodal in winter and spring, with nonthermoregulatory activities being performed primarily in the afternoon. There was a positive correlation between number of tortoises caught and rainfall per season, but activity levels and number of tortoises walking and feeding was not correlated with seasonal rainfall. Leopard tortoise activity behaviours responded to ambient temperature, but results indicate that activity is also initiated by the time since sunrise. [ABSTRACT FROM AUTHOR]

Idiopathic ventricular tachycardias, which occur in patients without structural heart disease, are a common entity, representing up to 10% of all ventricular tachycardias evaluated by cardiac electrophysiology services. Pregnancy can increase the incidence of various cardiac arrhythmias. Factors that can potentially promote arrhythmias in pregnancy include the effects of hormones, changes in autonomic tone, hemodynamic perturbations, hypokalemia, and underlying heart disease. Ventricular arrhythmias in pregnancy are repetitive monomorphic ventricular premature complexes and couplets that frequently originate at the right ventricular outflow tract. New onset symptomatic repetitive right ventricular outflow tract ventricular tachycardia during pregnancy has been inadequately reported in the literature. We present a case of symptomatic repetitive right ventricular outflow tract tachycardia that started during pregnancy and continued in the postpartum period, requiring curative treatment with electrophysiology study and radiofrequency ablation. [ABSTRACT FROM AUTHOR]

Sugar preferences and digestion of sugars in artificial fruit of different sugar types and concentrations were investigated in a South African facultative frugivore, the Cape white-eye (Zosterops virens). We studied sugar preferences, daily food and energy intake, and digestive efficiencies and transit times with birds that were fed artificial fruit diets comprising 6.6, 12.4 and 22% glucose and sucrose, respectively. Digestive transit rates of birds fed artificial fruit diets were faster for glucose compared with sucrose diets, irrespective of concentration. Birds showed increased food intake with decreasing glucose concentration, but showed no significant differences in these intake amounts with differing sucrose concentrations. Apparent assimilation efficiencies were lower than most nectar studies, and were generally higher for glucose fruit (79.3-85.6%) compared with sucrose fruit (69.0-78.4%). In choice tests, birds preferred sucrose over glucose of equivalent weight, irrespective of concentration. It appears likely that the Cape white-eye has high levels of sucrase activity, although further study is needed to verify this. [ABSTRACT FROM AUTHOR]

1. How body mass and body temperature influence metabolic rate has been of interest for decades. Today that interest can be seen in the form of debates over the proper scaling coefficients, and the mechanistic underpinnings of allometric models for metabolic rate in relation to body mass and body temperature. We tested explicit assumptions built into what we term the Arrhenius fractal supply (AFS) model of these relationships. This model, and its assumptions, is foundational to the controversial Metabolic Theory of Ecology. 2. In addition to predicting that the scaling exponent for body mass is 3/4, the AFS model originally predicted that metabolic responses to body temperature, measured as activation energies, should fall between 0·2 and 1·2 eV. More recently, the latter range was narrowed to 0·6 and 0·7 eV. 3. To test the AFS's predictions, we used multiple regression of ln(metabolic rate) as a function of ln(body mass) and 1/(body temperature) to fit the best scaling exponent for body mass to nine data sets of many diverse species. 4. For the majority of the data sets, in addition to not supporting a scaling exponent of 3/4, the analyses indicated that effects of body temperature sometimes fell outside the range of 0·6–0·7 eV, indicating that the predictions of the AFS model do not hold universally. 5. Effects of body temperature, however, did fall within the range of 0·2–1·2 eV. To aid interpretation of these results, we transformed activation energies into Q10s. At ecologically realistic temperatures, the values of Q10 that approximate activation energies of 0·2–1·2 eV ranged from c. 1·4 to 6·1 (where 6·1 is clearly unreasonably high). Hence, any model that predicts activation energies between 0·2 and 1·2 eV does not appear to be an informative scaling model at the organismal level. 6. The AFS model is foundational for the Metabolic Theory of Ecology. While we commend the attempt to incorporate scaling of metabolism into ecological theory, and the research it has inspired, we caution against using untested, and likely incorrect, assumptions as a foundation to a general theory of ecology. We recommend that scientists allow the data to determine the best model for incorporating energetics into ecological theory. [ABSTRACT FROM AUTHOR]

Irgarol 1051 is an s-triazine herbicide formulated with Cu2O in antifouling paints. Recent studies have shown that Irgarol 1051 inhibits coral photosynthesis at environmentally relevant concentrations, consistent with its mode of action as a photosystem II inhibitor. Related toxicologic effects of this herbicide on coral cellular physiology have not yet been investigated. We used cellular diagnostics to measure changes in 18 toxicologic cellular parameters in endosymbiotic algal (dinoflagellate) and cnidarian (host) fractions of the common branching coral Madracis mirabilis associated with in vivo 8- and 24-hour exposures to a nominal initial Irgarol 1051 concentration of 10 μg L−1. Responses measured were (1) xenobiotic response, which includes total and dinoflagellate multixenobiotic resistance (MXR), cnidarian cytochrome (CYP) P450−3 and P450-6 classes, cnidarian, and dinoflagellate glutathione-s-transferase (GST); (b) oxidative damage and response, which includes cnidarian and dinoflagellate Cu/Zn and Mn superoxide dismutase (SOD), cnidarian and dinoflagellate glutathione peroxidase (GPx), cnidarian catalase, and total protein carbonyl); (3) metabolic homeostasis, which includes chloroplast and invertebrate small heat-shock proteins (sHsp), cnidarian protoporphyrinogen oxidase IX (PPO), cnidarian ferrochelatase, and cnidarian heme oxygenase; and (4 ) protein metabolic condition, which includes cnidarian and dinoflagellate heat shock proteins (hsp70 and hsp60), total ubiquitin, and cnidarian ubiquitin ligase. Acute responses to Irgarol 1051 exposure included significant increases in total and dinoflagellate MXR, dinoflagellate Cu/Zn SOD, dinoflagellate chloroplast sHsp, and cnidarian PPO. Irgarol 1051 exposure resulted in decreases in cnidarian GPx, cnidarian ferrochelatase, cnidarian catalase, and cnidarian CYP 450-3 and -6 classes. Related implications of Irgarol 1051 exposure to coral cellular condition are discussed. [ABSTRACT FROM AUTHOR]

Habitat availability and use by bushbuck were investigated to assist with the compilation of a species-specific management plan. Eight bushbuck were fitted with radio-collars and tracked in their natural valley thicket and coastal bushveld-grassland habitat during summer. Bushbuck preferred short thicket habitat types which provided shelter and favoured forage plant species. Preference or avoidance of tall closed woodlands and high reedbeds by bushbuck was unclear and needs to be investigated further. Low closed grasslands were generally avoided, but they were still considered to be important as bushbuck feed on the fringes. [ABSTRACT FROM AUTHOR]

Geographic variation among four Common Fiscal subpopulations along an altitudinal gradient in South Africa demonstrated significant variation of 13 morphological features and 38 skeletal characters. Common Fiscals were largest in cooler, less humid, more arid areas and smallest in warmer, wetter, more humid localities, supporting Bergmann's Rule. Patterns of variation in morphology, anatomy and skeletal trends were significantly correlated with 11 climatic trends. Cardiopulmonary organ mass and blood haematocrit increased with altitude and reflected adaptations to low ambient temperatures and decreased oxygen pressures associated with high altitudes. These trends are concordant with those reported in various other avian species. [ABSTRACT FROM AUTHOR]

An electrophoretic allozyme study of the fiscal shrike Lanius collaris, a widely distributed sub-Saharan passerine, was undertaken to investigate altitudinal variation in genetic structure within this species. It is a sedentary bird with limited dispersal so that subpopulations may be expected to show genetic isolation by distance, which may have been enhanced by Pleistocene glaciation effects. The study area was a linear altitudinal transect of four localities in the eastern half of South Africa, which ranged from sea level to an altitude of 1800 m, with the geographic distance between the furthest subpopulations being 300 km. Fourteen (40%) of the 35 electrophoretic loci examined were polymorphic. The mean percentage of polymorphic loci within populations, mean heterozygosity and mean number of alleles per locus were 0.519, 0.272 and 1.60, respectively. These values were much higher than those reported for most other avian species. The negative FIS and FIT values indicated a small excess of heterozygotes. The populations are only weakly differentiated genetically (Fg^ = 0.076). Rogers' (1972) mean genetic distance (D) was 0.094, and Nei's (1978) mean unbiased genetic distance was 0.019. A phenogram (unweighted pair group method) and a phylogenetic tree (distance Wagner network), both based on Rogers' (1972) distance, showed some degree of geographical subgrouping. The high mean value for the effective number of migrants (Nm) among demes indicated that 3.04 individuals were exchanged among demes per generation. The mean value for local genetic differentiation iFgj) and Nm indicated levels of gene flow between the different localities of fiscal shrike subpopulations. The Mantel test indicated that there was no significant relationship between the F^f values and the geographical distances between sample pairs. This study showed that the isolation-by-distance model of subpopulation structure is inappropriate for these birds. Juvenile natal dispersal distances, female divorce rates (every three years) and the distance of travel of females (although low) appear to be sufficient to maintain high levels of polymorphism and heterozygosity. These levels of polymorphism and heterozygosity, together with large amounts of gene fiow and the general lack of spatial autocorrelation imply that the populations of L. collaris may be subject to high rates of random drift. High values of sample heterozygosity suggest that fiscal shrike subpopulations have been stable for a long period and that genetic diversity has accumulated within populations. The rates of migration suggest that the 'subpopulations' of fiscal shrike act more or less as a single population extending over at least 300 km. [ABSTRACT FROM AUTHOR]

There has been increased demand to widen access to university study. The Science Foundation Programme (SFP) at the University of KwaZulu-Natal (UKZN) (formerly Natal), Pietermaritzburg, is a year-long access course specifically for previously disadvantaged block students. Students in the SFP take five courses and performance in these is reflected in final marks. This determines whether they proceed into the faculty. However, little is known about whether or not this guarantees their success. One of the subjects SFP students take is biology. In the present study the performance of these students in their SFP biology course was assessed across years (1995-2000), as well as in the first year bioscience course. Assessment marks were also analysed to determine if they showed trends in the mastery of the skills and knowledge tested. The use of different forms of assessment as monitoring instruments appears to improve the reliability and validity of the final mark awarded to a student. It seems that passing their biology SFP does not necessarily mean that these students will perform well in their first year Biology course. This is a consequence of a myriad of academic and non-academic factors. However, in terms of ongoing curriculum development, the types of teaching and assessment used to award a final grade need to be examinationined. Development of language and higher order thinking skills need to be examinationined at both SFP biology and bioscience levels. [ABSTRACT FROM AUTHOR]

Little is known about snags in South African indigenous forests. Because of their value to wildlife, we initiated this study to quantify snag characteristics and dynamics. We also investigated forest structure (woody component and snags) and forest use by avian species of conservation concern. We examined tree species composition, abundance and tree size in eight Afromontane mixed Podocarpus forests in KwaZulu-Natal, South Africa. In addition, we investigated the succession of snags at the level of individual trees. Large Podocarpus species were less abundant in forests of the Dargle district than forests in the Creighton district. Mean diameter at breast height (dbh) of trees in the forests in these two districts differed significantly. Emergent and upper canopy trees (trees >50% of estimated 100% canopy height) were smaller in the Dargle district than those in the Creighton district. Although frequency of smaller trees (dbh = 10-60cm) compared with larger trees was high in both districts, forests in the Creighton district had more large trees. Snags were rare in all forests, but were larger (dbh) in forests of the Creighton district. The availability of large snags in these forests has implications for the conservation of secondary cavity nesting bird species including the Endangered Cape Parrot, Poicephalus robustus, as they are necessary for reproduction and recruitment of these birds. [ABSTRACT FROM AUTHOR]

Four populations of fiscal shrike Lanius collaris from South Africa were compared in respect of territory characteristics, territorial behaviour and time budgets. Shrikes held territories of the same size throughout the year. visual and vocal signals were used to maintain boundaries. Larger birds maintained larger territories, and were more involved in overt territorial behaviour and vigilance. They also spent less time foraging. Agonistic interactions were displayed on average 2-3 times an hour. Birds from larger territories had more interspecific encounters, while birds from smaller territories had more intraspecific encounters. The number of encounters in each territory was independent of season. Fiscal shrikes were >90% successful in territorial encounters against both conspecific and heterospecific intruders. Territory size was inversely proportional to perch density and was positively correlated with decreasing precipitation. Fiscal shrikes adapt to human-induced changes, increasing their use of artificial perches when natural perches were less common. [ABSTRACT FROM AUTHOR]

Foraging and territorial behaviour of Cape and Gurney's sugarbirds were studied in the Western Cape and eastern Free State of South Africa, respectively. Cape sugarbirds spent most of their time in territory defence and resting at all times of the day -- both at mid breeding season and at the end of the breeding season -- and only about ten percent of their time foraging. Cape sugarbirds may feed in the morning to replenish energy deficits and water imbalances experienced at night, and then maintain a high feeding rate at midday to maximize energy gain when nectar energy availability is greatest. Gurney's sugarbirds, by contrast, showed little variation in the amount of time spent feeding on nectar throughout the day. More dispersed or lower availability of food may have constrained vocal activity in Gurney's sugarbirds, which spent most of their time throughout the day perching silently on the tops of trees. In Cape sugarbirds, feeding preferences for particular Protea species changed in relation to their flowering seasons, and reduced inflorescence availability during the breeding season is related to increased perching and decreased territory defence at midday. [ABSTRACT FROM AUTHOR]

Explores the behavioral and electrophysiological central auditory process abilities of several aphasic individuals using a set of divided attention tasks. Areas associated with auditory processing involved in lesions resulting in aphasia; Evaluation of late auditory evoked potentials with and without distraction using an oddball paradigm.

Discusses the novels 'Barren Ground,' by Ellen Glasgow and 'O Pioneers!' by Willa Cather. Similarities of the novels; Way Glasgow shows the poverty of any link between marriage and religion; Analysis of the end of Cather's story.

The large vestibular aqueduct syndrome (LVAS) is a distinct clinical entity characterized by stepwise progressive sensorineural hearing loss associated with isolated enlargement of the vestibular aqueduct. A correlative clinical, audiologic, vestibular, cytogenetic, and radiographic analysis of a family with inherited LVAS was performed. The male proband and his affected brother are offspring of unaffected parents, and have no other abnormalities. Pedigree analysis suggests autosomal recessive or X-linked inheritance with variable expressivity of LVAS in this family. This study is the first description of familial inheritance of LVAS. LVAS may account for a significant number of patients with nonsyndromal, genetic sensorineural hearing loss. Future molecular analyses of this study family may identify the causative gene(s) in LVAS. [ABSTRACT FROM AUTHOR]

Hairy roots of Brassica napus (rape cv. Giant) were produced by cocultivating leaf and cotyledon explants with Agrobacterium rhizogenes strain A4T. The hairy roots grew prolifically on solid and in liquid media. Incorporation of ammonium sulphate or phosphinothricin (PPT) into the media reduced growth. PPT treatment reduced glutamine synthetase (GS) activity and increased the ammonia content of the hairy roots. We have found that PPT treatment also induces a loss of glutamine from the roots and this may influence root growth. To test this we grew hairy roots in a liquid medium containing 10 mM glutamine. This glutamine treatment overcame the PPT induced suppression of growth but also significantly increased GS activity, reduced ammonia accumulation and increased the levels of glutamate and asparagine. [ABSTRACT FROM AUTHOR]