Multivariate differential analyses of adolescents’ experiences of aggression in families

Aggression is part of South African society and has implications for the mental health of persons living in South Africa. If parents are aggressive adolescents are also likely to be aggressive and that will impact negatively on their mental health. In this article the nature and extent of adolescents’ experiences of aggression and aggressive behaviour in the family are investigated. A deductive explorative quantitative approach was followed. Aggression is reasoned to be dependent on aspects such as self-concept, moral reasoning, communication, frustration tolerance and family relationships. To analyse the data from questionnaires of 101 families (95 adolescents, 95 mothers and 91 fathers) Cronbach Alpha, various consecutive first and second order factor analyses, correlations, multiple regression, MANOVA, ANOVA and Scheffè/ Dunnett tests were used. It was found that aggression correlated negatively with the independent variables; and the correlations between adolescents and their parents were significant. Regression analyses indicated that different predictors predicted aggression. Furthermore, differences between adolescents and their parents indicated that the experienced levels of aggression between adolescents and their parents were small. Implications for education are given

The influence of soil particle surfaces and soil porosity on the biodegradation of key refuse leachate organic molecules.

Thesis (Ph.D.)-University of Natal, Pietermaritzburg, 1995.Many studies have been undertaken to determine the effects of soil and soil properties on migrating metal pollutants. Organic pollutants, however, in addition to their interactions with soil components , are also susceptible to degradation (catabolism) by microorganisms. Soil-microorganism-pollutant interactions have, traditionally, been studied in soil columns (microcosms). One of the shortcomings of column and in situ studies is that the identity and specific effect(s) of the soil component(s) affecting or influencing attenuation are not known and cannot readily be determined. Attenuation effects of the soil components are, therefore, difficult to interpret. ("Attenuation" in this context is the combined effects of both soil adsorption and microbial catabolism). Attenuation studies often only consider the physical conditions such as aeration, permeability, flow rate, temperature, etc. This approach assumes the soil to be a homogeneous matrix with no specific physico-chemical properties attributable to different components within the matrix. Soil physical factors suspected of influencing pollutant attenuation could be misleading without consideration of the physico-chemical interactions between soil components, microorganisms and pollutants. Adhesion of pollutants and microorganisms seems to be most important in this regard. The initial phase of this study was undertaken to examine the effects of three different soil materials on attenuation of key landfill leachate molecules. Examination of the effects of soil surface type on attenuation focused on adsorption / desorption of the pollutant molecules and microorganisms. These experiments sought to investigate the physico-chemical effects of soil, microorganism, pollutant interactions and were done as batch slurry experiments as well as in soil columns. Two soil horizons from the Inanda soil form (humic A and red apedal B) and the topsoil (vertic A) from a Rensburg soil form were used. The Inanda topsoil had a high organic matter content and both the topsoil and subsoil had a kaolinitic clay mineralogy; the Rensburg topsoil clay mineralogy was predominantly smectitic with a relatively low organic matter content. From the batch experiments, the adsorption of a hydrophobic molecule (naphthalene) and a heavy metal (cadmium) were found to be influenced to a significant extent by soil characteristics. Adsorption of naphthalene was due to the soil organic matter (SOM) content whereas cadmium adsorption was due to the cation exchange capacity (CEC) of the soil. Soil characteristics did not seem to have a significant influence on the adsorption of a water soluble compound such as phenol at the concentrations used. Attenuation of naphthalene was found to be affected by adsorption of the pollutant molecule (related to SOM) as well as the CEC of the soil. The attenuation of hydrophobic molecules can possibly be ascribed to the influence of CEC on the microbial population responsible for attenuation. This would seem to indicate interaction between the soil surfaces and the catabolizing microbial population. Desorption of the pollutant (and possibly also of the microbial population) was achieved by the addition of acetonitrile and methanol both of which reduced the polarity of the water. These solvents were also found to be toxic to the catabolizing microbial population at high concentrations. The toxicity thresholds of both solvents for catabolizing microorganisms differed significantly between soil- (> 15 %, v/v) and soil free (< 5 %, v/v) treatments. This discrepancy cannot be accounted for by adsorption and is ascribed to physico-chemical interaction between microorganisms and the soil surfaces. This interaction probably affords protection from, otherwise, toxic concentrations of solvents or metals. The important effects of soil surfaces on attenuation processes were thought to be due to the strong adsorption of naphthalene. Surface attachment of microorganisms was, however, also inferred from results obtained with phenol. This seemed to indicate that microbial attachment to soil surfaces was an important aspect in attenuation and did not occur only because of pollutant adsorption. Soil column experiments were made with both naphthalene and phenol. The naphthalene, which was adsorbed to the soil, did not leach from the columns to any appreciable extent. This was despite the addition of acetonitrile to some columns. This was probably due to greater microbial catabolism caused by desorption and, subsequent, increased soluble concentrations of the molecule. After extraction from the soil at the end of the experiment it was clear that the sterile controls held much higher concentrations of naphthalene than the experimental columns. The soil type and treatments showed little difference in the naphthalen concentration extracted from the soil columns. This did not reflect the differences found between soil materials in the batch experiments and was probably due to the masking effect of the soil physical factors on attenuation processes. Unlike naphthalene, phenol, because of its high solubility, was detected in the column leachates at relatively high concentrations. The phenol concentrations were much higher for the Inanda subsoil (approximately 4 mM) than the Inanda topsoil (approximately 2 mM) and Rensburg topsoil (< 1 mM). The Rensburg topsoil produced the lowest phenol concentrations in the leachate and this can probably be ascribed to the larger quantity of micropores in this soil. Thus, it seems that the soil physical features had a pronounced influence on attenuation. Whether this effect was directly on the studied molecule or indirectly, because of the effects on the microbial population, is not known. Inoculation of the columns with a phenol catabolizing population had only a slight increased effect on leachate phenol concentrations from all columns. This increased effect was, however, only prolonged in the case of the Inanda subsoil. The flow rate through the columns affected leachate phenol concentration which was lower with a slower flow rate and, thus, longer retention time. From the column experiments soil physical parameters were suspected of influencing, and possibly overriding, the soil surface effects on microbial activity (capacity to catabolize a organic molecule of interest). Soil porosity, as caused by different soil materials, was suspected of being the most important soil physical parameter influencing microbial activity. To investigate the potential effect of soil porosity, relatively homogeneous porous media i.e. chromatography packing material and acid washed sand were used. These materials had more defined and distinct porosities and were considered to be suitable for investigating the fundamental influence of porosity on microbial activity. Saturated continuous flow columns were used and three types of packing configurations were tested: chromatography packing (CHROM) material (porous particles); acid washed sand (non-porous) (AWS); and a 1: 1 (w/w) mixture of chromatography packing and acid washed sand (MIX). Only a single water soluble molecule, phenol, was used in this phase of the investigation. Bacterial filtration ("filtration" as a component of "attenuation'') was found to be highest for the CHROM and lowest for the AWS materials. This difference in microbial retention affected the phenol catabolism in response to increased column dilution rates. The CHROM and MIX materials had distinctly different porosities than that of the AWS, due to the internal porosity of the chromatography packing. This greater pore size distribution in the MIX and CHROM packing materials created pores with different effective pore dilution rates within the microcosms at similar overall flow rates. The greater pore size distribution in the MIX and CHROM packing materials facilitated pore colonization since some pores did not participate, or conduct, mass flow as occurred in macropores. This led to different microcolonization effects in the macro- vs micropores. Since the MIX and CHROM packing materials had more micropore colonization sites these packing materials showed a greater range of substrate affinities (i.e. Ks values) for the phenol substrate. The extent to which micropore colonization occurred could be detected by the effect it had on phenol breakthrough curves. In the MIX and CHROM materials, microbial colonization caused blocking of micropores with a subsequent effect on the phenol breakthrough curves. The AWS material, however, which had a low inherent microporosity, showed microbially induced microporosity probably due to biofilm development. The fact that the MIX and CHROM packing materials facilitated micropore colonization was also responsible for the greater resistance to, and the recovery from , potentially inhibitory cadmium concentrations. This effect was also apparent in the presence of acetonitrile, although this effect was not identical to that observed with cadmium. Finally, column pressure build up as a function of pore clogging was determined and was found to occur in the order AWS > MIX > CHROM. This was most likely due to fewer potential liquid flow paths with a higher blocking potential in the AWS. Extrapolation of the fundamentals of the above findings led to the conclusion that soil surface- and soil porosity effects are extremely important factors in determining the behavior of soils as bioreactors

The Fontan epidemic: population projections from the Australia and New Zealand Fontan registry

Background: The number and age demographic of the future Fontan population is unknown

Assignment of epidemiological lineages in an emerging pandemic using the pangolin tool.

Funder: Oxford Martin School, University of OxfordThe response of the global virus genomics community to the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic has been unprecedented, with significant advances made towards the 'real-time' generation and sharing of SARS-CoV-2 genomic data. The rapid growth in virus genome data production has necessitated the development of new analytical methods that can deal with orders of magnitude of more genomes than previously available. Here, we present and describe Phylogenetic Assignment of Named Global Outbreak Lineages (pangolin), a computational tool that has been developed to assign the most likely lineage to a given SARS-CoV-2 genome sequence according to the Pango dynamic lineage nomenclature scheme. To date, nearly two million virus genomes have been submitted to the web-application implementation of pangolin, which has facilitated the SARS-CoV-2 genomic epidemiology and provided researchers with access to actionable information about the pandemic's transmission lineages

Re-evaluation of the near infrared spectra of mitochondrial cytochrome c oxidase: Implications for non invasive in vivo monitoring of tissues

We re-determined the near infrared (NIR) spectral signatures (650-980 nm) of the different cytochrome c oxidase redox centres, in the process separating them into their component species. We confirm that the primary contributor to the oxidase NIR spectrum between 700 and 980 nm is cupric CuA, which in the beef heart enzyme has a maximum at 835 nm. The 655 nm band characterises the fully oxidised haem a3/CuBbinuclear centre; it is bleached either when one or more electrons are added to the binuclear centre or when the latter is modified by ligands. The resulting 'perturbed' binuclear centre is also characterised by a previously unreported broad 715-920 nm band. The NIR spectra of certain stable liganded species (formate and CO), and the unstable oxygen reaction compounds P and F, are similar, suggesting that the latter may resemble the stable species electronically. Oxidoreduction of haem a makes no contribution either to the 835 nm maximum or the 715 nm band. Our results confirm the ability of NIRS to monitor the CuAcentre of cytochrome oxidase activity in vivo, although noting some difficulties in precise quantitative interpretations in the presence of perturbations of the haem a3/CuBbinuclear centre

Pediatric Bacterial Meningitis Surveillance in the World Health Organization African Region Using the Invasive Bacterial Vaccine-Preventable Disease Surveillance Network, 2011-2016.

BACKGROUND: Bacterial meningitis is a major cause of morbidity and mortality in sub-Saharan Africa. We analyzed data from the World Health Organization's (WHO) Invasive Bacterial Vaccine-preventable Diseases Surveillance Network (2011-2016) to describe the epidemiology of laboratory-confirmed Streptococcus pneumoniae (Spn), Neisseria meningitidis, and Haemophilus influenzae meningitis within the WHO African Region. We also evaluated declines in vaccine-type pneumococcal meningitis following pneumococcal conjugate vaccine (PCV) introduction. METHODS: Reports of meningitis in children <5 years old from sentinel surveillance hospitals in 26 countries were classified as suspected, probable, or confirmed. Confirmed meningitis cases were analyzed by age group and subregion (South-East and West-Central). We described case fatality ratios (CFRs), pathogen distribution, and annual changes in serotype and serogroup, including changes in vaccine-type Spn meningitis following PCV introduction. RESULTS: Among 49 844 reported meningitis cases, 1670 (3.3%) were laboratory-confirmed. Spn (1007/1670 [60.3%]) was the most commonly detected pathogen; vaccine-type Spn meningitis cases declined over time. CFR was the highest for Spn meningitis: 12.9% (46/357) in the South-East subregion and 30.9% (89/288) in the West-Central subregion. Meningitis caused by N. meningitidis was more common in West-Central than South-East Africa (321/954 [33.6%] vs 110/716 [15.4%]; P < .0001). Haemophilus influenzae (232/1670 [13.9%]) was the least prevalent organism. CONCLUSIONS: Spn was the most common cause of pediatric bacterial meningitis in the African region even after reported cases declined following PCV introduction. Sustaining robust surveillance is essential to monitor changes in pathogen distribution and to inform and guide vaccination policies

Hospital inpatient costs for single ventricle patients surviving the Fontan procedure

We estimated the inpatient resource use for a Fontan patient from birth to adulthood and explored factors that might induce cost differences (2014 US dollar). Inpatient costing records from 4 hospitals with greatest numbers of Fontan patients in Australia and New Zealand were linked with the Fontan registry database. Inpatient records between July 1995 and September 2014 for 420 Fontan patients were linked, and the most frequent primary diagnoses were hypoplastic left heart syndrome (20.7%), tricuspid atresia (19.7%), and double inlet left ventricle (17.1%). The mean hospital cost for a Fontan patient from birth to 18 years of age was estimated to be $390,601 (95$264,703 to $516,499), corresponding to 164 (95$219,482 (95% CI $202,410 to$236,553) and the cost thereafter over 15 years was $146,820 (95$44,409 to $249,231), corresponding to 82 (95% CI 72 to 92) and 65 (95% CI 18 to 112) inpatient days, respectively. Costs were higher in male and hypoplastic left heart syndrome patients in the staged procedures period (

Frontal sinuses and human evolution

The frontal sinuses are cavities inside the frontal bone located at the junction between the face and the cranial vault and close to the brain. Despite a long history of study, understanding of their origin and variation through evolution is limited. This work compares most hominin species’ holotypes and other key individuals with extant hominids. It provides a unique and valuable perspective of the variation in sinuses position, shape, and dimensions based on a simple and reproducible methodology. We also observed a covariation between the size and shape of the sinuses and the underlying frontal lobes in hominin species from at least the appearance of Homo erectus. Our results additionally undermine hypotheses stating that hominin frontal sinuses were directly affected by biomechanical constraints resulting from either chewing or adaptation to climate. Last, we demonstrate their substantial potential for discussions of the evolutionary relationships between hominin species

Effects of antiplatelet therapy on stroke risk by brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases: subgroup analyses of the RESTART randomised, open-label trial

Background Findings from the RESTART trial suggest that starting antiplatelet therapy might reduce the risk of recurrent symptomatic intracerebral haemorrhage compared with avoiding antiplatelet therapy. Brain imaging features of intracerebral haemorrhage and cerebral small vessel diseases (such as cerebral microbleeds) are associated with greater risks of recurrent intracerebral haemorrhage. We did subgroup analyses of the RESTART trial to explore whether these brain imaging features modify the effects of antiplatelet therapy