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Contains fulltext : 306425.pdf (Publisher’s version ) (Closed access), Electrodiagnostic studies (EDx) are frequently performed in the diagnostic evaluation of peripheral nerve disorders. There is increasing interest in the use of newer, alternative diagnostic modalities, in particular imaging, either to complement or replace established EDx protocols. However, the evidence to support this approach has not been expansively reviewed. In this paper, diagnostic performance data from studies of EDx and other diagnostic modalities in common peripheral nerve disorders have been analyzed and described, with a focus on radiculopathy, plexopathy, compressive neuropathies, and the important neuropathy subtypes of Guillain-Barré syndrome, chronic inflammatory demyelinating polyradiculoneuropathy (CIDP), vasculitic neuropathy and diabetic neuropathy. Overall EDx retains its place as a primary diagnostic modality in the evaluated peripheral nerve disorders. Magnetic resonance imaging and ultrasound have developed important complementary diagnostic roles in compressive and traumatic neuropathies and atypical CIDP, but their value is more limited in other neuropathy subtypes. Identification of hourglass constriction in nerves of patients with neuralgic amyotrophy may have therapeutic implications. Investigation of radiculopathy is confounded by poor correlation between clinical features and imaging findings and the lack of a diagnostic gold standard. There is a need to enhance the literature on the utility of these newer diagnostic modalities., 01 juni 2024

[Objective]: The aim of this study was to describe growth during puberty in young people with vertically acquired HIV. [Design]: Pooled data from 12 paediatric HIV cohorts in Europe and Thailand. [Methods]: One thousand and ninety-four children initiating a nonnucleoside reverse transcriptase inhibitor or boosted protease inhibitor based regimen aged 1–10 years were included. Super Imposition by Translation And Rotation (SITAR) models described growth from age 8 years using three parameters (average height, timing and shape of the growth spurt), dependent on age and height-for-age z-score (HAZ) (WHO references) at antiretroviral therapy (ART) initiation. Multivariate regression explored characteristics associated with these three parameters. [Results]: At ART initiation, median age and HAZ was 6.4 [interquartile range (IQR): 2.8, 9.0] years and −1.2 (IQR: −2.3 to −0.2), respectively. Median follow-up was 9.1 (IQR: 6.9, 11.4) years. In girls, older age and lower HAZ at ART initiation were independently associated with a growth spurt which occurred 0.41 (95% confidence interval 0.20–0.62) years later in children starting ART age 6 to 10 years compared with 1 to 2 years and 1.50 (1.21–1.78) years later in those starting with HAZ less than −3 compared with HAZ at least −1. Later growth spurts in girls resulted in continued height growth into later adolescence. In boys starting ART with HAZ less than −1, growth spurts were later in children starting ART in the oldest age group, but for HAZ at least −1, there was no association with age. Girls and boys who initiated ART with HAZ at least −1 maintained a similar height to the WHO reference mean. [Conclusion]: Stunting at ART initiation was associated with later growth spurts in girls. Children with HAZ at least −1 at ART initiation grew in height at the level expected in HIV negative children of a comparable age.

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Sea urchins can have a significant influence upon the ecological structure of coral reefs through bioerosion of substrata and also by affecting competition for space. They are important grazers in many marine systems and can cause major ecosystem changes when their populations reach high levels (generally after a decline in the numbers of their fish predators). However, the relative importance of the role of sea urchins in influencing the composition and structure of coral reef habitats has rarely been explored. This study is linked to the CSIRO Wealth from Oceans Ningaloo Collaboration Cluster, Component 1: Habitat Mapping and Biodiversity. It has so far examined coral reef habitats and macroinvertebrate (particularly urchins) distribution and abundance within Ningaloo Marine Park. Field sampling has been undertaken at over 100 sites within the Park, focussing on near shore, lagoonal and back reef areas within Sanctuary zones and adjacent Recreation zones. Data analyses so far indicate that the distribution of urchins is not affected by the management zones of the park (i.e. no significant evidence has been found of indirect effects from fishing of urchin predators). However, habitat type has a major influence on urchin distribution, e.g. urchin populations were higher on nearshore intertidal and sub-tidal reef platforms, lagoonal patch reefs and shallow backreef platforms than other habitats. In coral reefs in other parts of the world, unusually high urchin populations can indicate overfishing. So far, this study has found no indication of fishing pressure indirectly affecting urchin densities, which suggests that the current zoning may be effective. However, further analyses of the data, particularly those from the nearshore sanctuary areas where shore based fishing activities are allowed, are yet to be completed. If fishing pressure is having an effect, it is likely to be seen in those areas where urchin abundance is predicted to be highest.

Conventional regulation relies on the modelling of physical systems to connect changes in human activity to the metric of system performance. Management of complex natural systems also requires models that link patterns of human impact to changes in the relevant metric of system performance. Unfortunately however, the determination of all but the most simple cause and effect pathways regarding biological systems, including mangroves, remains largely incomplete. Present research outcomes now allow us to gain some idea of the pathways often associated with mangrove habitat degradation or loss. Conceptual modelling illustrates that, while a number of natural factors affect mangroves, anthropogenic impacts can be fairly easily defined. This allows us to focus our attention when considering activities that may impact upon these ecosystems. This paper will describe cause/effect pathways applicable to all mangrove systems and the impacts associated with them.

A Carbon nano tube (CNT)–Ferrihydrite nanocomposite was synthesized through precipitation in ethyl alcohol media. Its detailed characterization was carried out using XRD, SEM, FTIR and EDAX. The adsorption characteristics of the composite for As(V) removal were carried out as function of pH, adsorbent dose, As(V) concentration and contact time. Although pure CNT did not show any significant adsorption, CNT-Ferrihydrite proved to be a good adsorbent for arsenic. With increase in pH, the As(V) adsorption on the composite first decreased up to pH 5.0, thereafter it remained nearly constant. The adsorption followed the Langmuir isotherm model and from the data its monolayer adsorption capacity was estimated to be 44.1 mg/g. The adsorption data were best described by the pseudo-second order kinetic model.

The dwarf sawfish, Pristis clavata, was captured in marine waters of King Sound and estuarine waters of the Fitzroy, May and Robinson Rivers, in the Kimberley region of Western Australia. Observations of sexual maturity and annuli present on vertebrae suggest that the estuarine waters of at least the Fitzroy River act as a nursery for the species, where immature individuals may remain for at least 3 years. The capture of immature individuals in excess of 2,330 mm TL during the current study in addition to Peverell's (Peverell in Environ Biol Fishes 73:391-402, 2005) record of a mature male measuring 3,060 mm TL implies that the species may attain far greater lengths than previously reported and that the common name may not be entirely appropriate. In contrast to the sympatric freshwater sawfish Pristis microdon, the number of rostral teeth of individual P. clavata can not be used to differentiate males from females, with both sexes possessing an average of 42 rostral teeth.

We assessed natural rates of floral abortion in four common mangrove species from nor-them Australia and subsequently manipulated pollination experimentally. Sonneratia alba J. Smith exhibited the highest rate of fruit set of the four species (23%), indicating this mangrove was best able to utilise the natural pollination opportunities provided. Fruit set in S. alba appeared, however, to be pollinator limited, as large increases in fruit set occurred after manual cross-pollination of flowers. Avicennia marina (Forsk.) Vierh. had the highest rate of natural pollination, but fruit set was lower (15%) and appeared to be impeded by resource limitations. Although a range of insects visited Ceriops australis (C.T. White) Ballment, T.J. Sur & Stoddart, the rate of fruit set was low (3%) and the capacity for flower fertilisation limited. despite evidence of autogamy in this species. There was an indication of both resource and pollinator limitation in C. australis. Rhizophora stylosa Griff. exhibited limited fruit set (0.5%), possibly due to limiting maternal resources and the lack of adaptation of flowers to either animal or wind pollination. Large increases in fruit set were recorded after manual cross-pollination of R. stylosa flowers. R. stylosa and C. australis, characterised by resource rich propagules with long periods of development, both aborted a large proportion of propagules during the fruit maturation process.

Mangrove communities in the tropical north of Australia are some of the most species rich in the world, yet surprisingly little is known of their reproductive and vegetative phenology. This study investigated the phenology of four mangrove species: Avicennia marina (Forsk.) Vierh., Ceriops australis ( C. T. White) Ballment, T. J. Sm M Stoddart, Rhizophora stylosa Griff. and Sonneratia alba J. Smith, in Darwin Harbour over 24 months. Investigations included documenting the flowering and fruiting phenology, periods of leaf flush and leaf longevity. Flowering in these mangroves generally occurred during the dry season (June-October), with the exception of R. stylosa in which flowering occurred in the middle of the wet (December-February). Fruits and propagules were released in the dry and 'build up' periods (August-November), with the exception of A. marina, which released propagules in the middle of the wet season. Fruit and/or propagule maturation took less than 2 months in A. marina and S. alba, whereas in C. australis and R. stylosa maturation took 12 and 11 months, respectively. Timing of new leaf production generally coincided with the wet season, after the flowering and fruiting periods of each of the four species. Periods of leaf flush and leaf fall were often closely linked, and species with longer-lived leaves produced fewer leaves at each period of leaf flush. Maximum leaf longevity varied considerably among mangroves, ranging from 8 months in the lower canopy of S. alba to more than 24 months in C. australis. There was also large variability in leaf longevity among different regions of the canopy, with shade leaves generally living longer than sun leaves, and leaves in the upper canopy (3-7 m) longer than those in the lower regions (0-3 m).

The aquatic flora of Leschenault Inlet is similar to that in other southern estuaries, except that Leschenault Inlet has a relatively high diversity of red algae, and Hormophysa triquetra is the dominant brown alga. Total plant biomass was generally 3 000-5 000 t dry weight, with a maximum in spring. There were large differences in the biomass of seagrass and macroalgae between individual surveys, but in general seagrass biomass and total macroalgal biomass appear relatively stable in the long term. Total plant biomass per unit area in Leschenault Inlet was similar to that in the Peel-Harvey estuarine system. The major difference was the relative proportions of total biomass accounted for by seagrass, brown algae and green algae. Macrophyte biomass in Peel-Harvey is dominated by green algae, whereas in Leschenault Inlet seagrass and brown algae are dominant. The inlet appears to have been in an acceptable state under the nutrient loading regime and hydrodynamic conditions of the years when the surveys were carried out.

The influence of salinity on Typha orientalis and Juncus kraussii was documented in experiments on germination of seeds and on growth of seedlings and adult, rhizome-bearing plants. Juncus was more salt-tolerant than Typha at all three life-history stages, but salt tolerance increased with plant age for both species. Although seeds of both species germinated at 0 and 5 ppt, the germination data overestimated salt tolerance for Typha. Only the newly emerged seedlings of Juncus were capable of growth after removal from the 5 ppt NaCl solution to fresh water. Typha seedlings that initiated growth at 0 ppt grew well at 5 ppt but not at 10 ppt, while Juncus seedlings were tolerant of 10 ppt. Although the 20 ppt treatment caused high mortality of Juncus seedlings, the 10 ppt treatment mainly reduced growth. Adult plants of Typha, which were collected from the field, survived the 20 ppt treatment, while adult Juncus survived the 40 ppt treatment. The presence of salt (10–40 ppt) shortened the growing season for adult, rhizome-bearing plants of both Juncus and Typha, with a lower maximum and earlier peak in total leaf length and maximum leaf number. Thus, the greater biomass in fresh water was achieved primarily through a longer growth period, rather than a greatly accelerated growth rate. Interactions between the two species were explored in mixed-species culture of both seedlings and adult rhizome-bearing plants. Interspecific interactions were present at low salinity, but results differed for seedlings and adult plants. Typha seedlings failed to outgrow Juncus seedlings (at 5 ppt) but adult plants of Typha outgrew Juncus (at 0 ppt). Relative yields (biomass in mixed/pure pots) for Juncus and Typha seedlings were 0.85 and 0.26 at 5 ppt. Relative yields of adult plants were 0.24 for Juncus and 1.20 for Typha at 0 ppt. For both seedlings and adults, the species that ultimately dominated the mixed-species pots produced just as much total biomass as in pure-species pots, even

Natural iron ores were tested as adsorbents for the removal of arsenic from contaminated water at varying pH, adsorbent dose, contact time, arsenic concentration, and presence of interfering species. Iron ore containing mostly haematite at pH 4.5 to 6.5 was most effective. The experimental data fitted the modelling used. The presence of silicate and phosphate reduced arsenic adsorption, sulphate and chloride slightly improved it; phosphate interference would necessitate relatively high doses of adsorbent to reduce arsenic levels to drinking water standards., Natural iron ores were tested as adsorbents for the removal of arsenic from contaminated water at varying pH, adsorbent dose, contact time, arsenic concentration, and presence of interfering species. Iron ore containing mostly haematite at pH 4.5 to 6.5 was most effective. The experimental data fitted the modelling used. The presence of silicate and phosphate reduced arsenic adsorption, sulphate and chloride slightly improved it; phosphate interference would necessitate relatively high doses of adsorbent to reduce arsenic levels to drinking water standards.