Effect of human telomerase reverse transcriptase transfection on differentiation in BeWo choriocarcinoma cells

Arrest of proliferation is one of the prerequisites for differentiation of cytotrophoblasts into syncytiotrophoblasts, and thus during differentiation telomerase activity, as well as human telomerase reverse transcriptase (hTERT) expression, is down-regulated. Considering this, it is of interest to investigate whether syncytium formation can be delayed by prolonging the expression of telomerase in cytotrophoblasts. BeWo cells were transfected with pLPC-hTERT retroviral vector and the reverse transcription-polymerase chain reaction analysis for hTERT mRNA concentrations in the transfected cells revealed a several-fold increase in hTERT mRNA compared with the cells transfected with empty vector, and this confirmed that the transfection was successful. An increase in the proliferation, as assessed by bromodeoxyuridine incorporation assay, as well as an increase in mRNA and protein concentration of various cyclins and proliferating cell nuclear antigen, was noticed. The effect of hTERT transfection was also assessed after the addition of forskolin to induce differentiation and it was observed that cell–cell fusion was delayed and differentiation did not occur in hTERT-transfected cells. However, the effects seen were only transient as stable transfection was not possible and the cells were undergoing apoptosis after 72 h, which suggested that apart from hTERT other factors might be important for immortalization of BeWo cells.

The effect of light on cognitive performance of partially sleep-deprived young drivers

Sleepiness remains a primary cause of road crashes, the major cause of death in young adults. Light is known to produce a direct alerting effect, but little is known about its effects on sleepy drivers. This study aimed to compare the effect of blue-green light and caffeine on young drivers’ cognitive performance after chronic-partial sleep loss.

The effect of endophyte on the performance of irrigated perennial ryegrasses in subtropical Australia

The effect of fungal endophyte (Neotyphodium lolii) infection on the performance of perennial ryegrass (Lolium perenne) growing under irrigation in a subtropical environment was investigated. Seed of 4 cultivars, infected with standard (common toxic or wild-type) endophyte or the novel endophyte AR1, or free of endophyte (Nil), was sown in pure swards, which were fertilised with 50 kg N/ha.month. Seasonal and total yield, persistence, and rust susceptibility were assessed over 3 years, along with details of the presence of endophyte and alkaloids in plant shoots. Endophyte occurrence in tillers in both the standard and AR1 treatments was above 95% for Bronsyn and Impact throughout and rose to that level in Samson by the end of the second year. Meridian AR1 only reached 93% while, in the standard treatment, the endophyte had mostly died before sowing. Nil Zendophyte treatments carried an average of ?0.6% infection throughout. Infection of the standard endophyte was associated with increased dry matter (DM) yields in all 3 years compared with no endophyte. AR1 also significantly increased yields in the second and third years. Over the full 3 years, standard and AR1 increased yields by 18% and 11%, respectively. Infection with both endophytes was associated with increased yields in all 4 seasons, the effects increasing in intensity over time. There was 27% better persistence in standard infected plants compared with Nil at the end of the first year, increasing to 198% by the end of the experiment, while for AR1 the improvements were 20 and 134%, respectively. The effect of endophyte on crown rust (Puccinia coronata) infection was inconsistent, with endophyte increasing rust damage on one occasion and reducing it on another. Cultivar differences in rust infection were greater than endophyte effects. Plants infected with the AR1 endophyte had no detectable ergovaline or lolitrem B in leaf, pseudostem, or dead tissue. In standard infected plants, ergovaline and lolitrem B were highest in pseudostem and considerably lower in leaf. Dead tissue had very low or no detectable ergovaline but high lolitrem B concentrations. Peramine concentration was high and at similar levels in leaf and pseudostem, but not detectable in dead material. Concentration was similar in both AR1 and standard infected plants. Endophyte presence appeared to have a similar effect in the subtropics as has been demonstrated in temperate areas, in terms of improving yields and persistence and increasing tolerance of plants to stress factors.

Effect of feeding sorghum ergot (Claviceps africana) to sows during mid-lactation on plasma prolactin and litter performance

Diets containing 3% sorghum ergot (16 mg alkaloids/kg, including 14 mg dihydroergosine/kg) were fed to 12 sows from 14 days post-farrowing until weaning 14 days later, and their performance was compared with that of 10 control sows. Ergot-fed sows displayed a smaller weight loss during lactation of 24 kg/head vs. 29 kg/head in control sows (p > 0.05) despite feed consumption being less (61 kg/head total feed intake vs. 73 kg/head by control sows; p < 0.05). Ergot-fed sows had poorer weight gain of litters over the 14-day period (16.6 kg/litter vs. 28.3 kg/litter for controls; p < 0.05) despite an increase in consumption of creep feed by the piglets from the ergot-fed sows (1.9 kg/litter compared with 1.1 kg/litter by the control; p > 0.05). Sow plasma prolactin was reduced with ergot feeding after 7 days to 4.8 μg/l compared with 15.1 μg/l in the control sows (p < 0.01) and then at weaning was 4.9 μg/l compared with 8.0 μg/l (p < 0.01) in the control sows. Two sows fed ergot ceased lactation early, and the above sow feed intakes, body weight losses with litter weight gains and creep consumption indirectly indicate an ergot effect on milk production.

Effect of substrate temperature on the physical properties of dc magnetron sputtered CuAlO2 films

Copper aluminum oxide films were prepared by direct current (dc) reactive magnetron sputtering under various substrate temperatures in the range of 303–648 K and systematically studied their physical properties. The physical properties of the films were strongly affected by the substrate temperature. The films formed at substrate temperatures <373 K were amorphous while those deposited at higher substrate temperatures (≥373 K) were polycrystalline in nature. The electrical properties of the films enhanced with substrate temperature due to the improved crystallinity. The Hall mobility of 9.4 cm2/V s and carrier concentration of 3.5 × 1017 cm−3 were obtained at the substrate temperature of 573 K. The optical band gap of the films decreased from 3.87 to 3.46 eV with the increase of substrate temperature from 373 to 573 K.

Effect of changes in hook pattern and size on catch rate, hooking location, injury and bleeding for a number of tropical reef fish species

The Queensland Great Barrier Reef line fishery in Australia is regulated via a range of input and output controls including minimum size limits, daily catch limits and commercial catch quotas. As a result of these measures a substantial proportion of the catch is released or discarded. The fate of these released fish is uncertain, but hook-related mortality can potentially be decreased by using hooks that reduce the rates of injury, bleeding and deep hooking. There is also the potential to reduce the capture of non-target species though gear selectivity. A total of 1053 individual fish representing five target species and three non-target species were caught using six hook types including three hook patterns (non-offset circle, J and offset circle), each in two sizes (small 4/0 or 5/0 and large 8/0). Catch rates for each of the hook patterns and sizes varied between species with no consistent results for target or non-target species. When data for all of the fish species were aggregated there was a trend for larger hooks, J hooks and offset circle hooks to cause a greater number of injuries. Using larger hooks was more likely to result in bleeding, although this trend was not statistically significant. Larger hooks were also more likely to foul-hook fish or hook fish in the eye. There was a reduction in the rates of injuries and bleeding for both target and non-target species when using the smaller hook sizes. For a number of species included in our study the incidence of deep hooking decreased when using non-offset circle hooks, however, these results were not consistent for all species. Our results highlight the variability in hook performance across a range of tropical demersal finfish species. The most obvious conservation benefits for both target and non-target species arise from using smaller sized hooks and non-offset circle hooks. Fishers should be encouraged to use these hook configurations to reduce the potential for post-release mortality of released fish.

The effect of habitat and environmental history on otolith chemistry of barramundi Lates calcarifer in estuarine populations of a regulated tropical river

We examine the microchemistry of otoliths of cohorts of a fished shed population of the large catadromous fish, barramundi Lates calcarifer from the estuary of a large tropical river. Barramundi from the estuary of the large, heavily regulated Fitzroy River, north eastern Australia were analysed by making transects of 87Sr/86Sr isotope and trace metal/Ca ratios from the core to the outer edge. Firstly, we examined the Sr/Ca, Ba/Ca, Mg/Ca and Mn/Ca and 87Sr/86Sr isotope ratios in otoliths of barramundi tagged in either freshwater or estuarine habitats that were caught by the commercial fishery in the estuary. We used 87Sr/86Sr isotope ratios to identify periods of freshwater residency and assess whether trace metal/Ca ratios varied between habitats. Only Sr/Ca consistently varied between known periods of estuarine or freshwater residency. The relationships between trace metal/Ca and river flow, salinity, temperature were examined in fish tagged and recaptured in the estuary. We found weak and inconsistent patterns in relationships between these variables in the majority of fish. These results suggest that both individual movement history within the estuary and the scale of environmental monitoring were reducing our ability to detect any patterns. Finally, we examined fish in the estuary from two dominant age cohorts (4 and 7 yr old) before and after a large flood in 2003 to ascertain if the flood had enabled fish from freshwater habitats to migrate to the estuary. There was no difference in the proportion of fish in the estuary that had accessed freshwater after the flood. Instead, we found that larger individuals with each age cohort were more likely to have spent a period in freshwater. This highlights the need to maintain freshwater flows in rivers. About half the fish examined had accessed freshwater habitats before capture. Of these, all had spent at least their first two months in marine salinity waters before entering freshwater and some did not enter freshwater until four years of age. This contrasts with the results of several previous studies in other parts of the range that found that access to freshwater swamps by larval barramundi was important for enhanced population productivity and recruitment.

Effect of Structural Modification on the Quantum-Size Effect in II-VI Semiconducting Nanocrystals

The electronic structure of group II-VI semiconductors in the stable wurtzite form is analyzed using state-of-the-art ab initio approaches to extract a simple and chemically transparent tight-binding model. This model can be used to understand the variation in the bandgap with size, for nanoclusters of these compounds. Results complement similar information already available for same systems in the zinc blende structure. A comparison with all available experimental data on quantum size effects in group II-VI semiconductor nanoclusters establishes a remarkable agreement between theory and experiment in both structure types, thereby verifying the predictive ability of our approach. The significant dependence of the quantum size effect on the structure type suggests that the experimental bandgap change at a given size compared to the bulk bandgap, may be used to indicate the structural form of the nanoclusters, particularly in the small size limit, where broadening of diffraction features often make it difficult to unambiguously determine the structure.

Amide-Based Glutathione Peroxidase Mimics: Effect of Secondary and Tertiary Amide Substituents on Antioxidant Activity

A series of secondary and tertiary amide-substituted diselenides were synthesized and studied for their GPx-like antioxidant activities using H2O2 Cum-OOH, and tBuOOH as substrates and PhSH as thiol co-substrate.The effect of substitution at the free -NH group of the amide moiety in the sec-amide-based diselenides on GPx activity was analyzed by detailed experimental and theoretical methods. It is observed that substitution at the free -NH group significantly enhances the GPx-like activities of the sec-amide-based diselenides, mainly by reducing the Se center dot center dot center dot O nonbonded interactions. The reduction in strength of the Se center dot center dot center dot O interaction upon introduction of N,N-dialkyl substituents not only prevents the undesired thiol exchange reactions, but also reduces the stability of selenenyl sulfide intermediates. This leads to a facile disproportionation of the selenenyl sulfide to the corresponding diselenide, which enhances the catalytic activity. The mechanistic investigations indicate that the reactivity of diselenides having sec-or tert-amide moieties with PhSH is extremely slow; indicating that the first step of the catalytic cycle involves the reaction between the diselenides and peroxide to produce the corresponding selenenic and seleninic acids.

Effect of Pressure on Polymer Ignition

Auto-ignition temperature of polystyrene, poly(vinyl chloride) and carboxy terminated polybutadiene has been measured at various oxygen pressures (1-28 atm) in a high pressure differential thermal analysis assembly at a heating rate of 10°C/min. The exothermic peak appears between 250-350°C in polystyrene and poly(vinyl chloride) and between 150-200°C for carboxy terminated polybutadiene. Ignition appears to be controlled by in situ forma tion and degradation of polymeric peroxides. Inverse dependence of ignition temperature on oxygen pressure is explained by the rate equation which con siders that ignition of a particular sample, of a fixed geometry, occurs when gasification rate reaches a unique critical value.

Public trust in Australian charities: Accounting for cause and effect

This paper reports on a study of the key determinants of public trust in charitable organisations, using survey data commissioned by the Australian Charities and Not-for-profits Commission. Data analysis used partial least squares structural equation modelling to examine both antecedents of trust and the influence of trust on charitable donative intentions. We found that people tend to trust charities with which they are familiar, and which are transparent in their reporting. Organisational size, importance, reputation and national significant were also antecedents of trust. People are more likely to volunteer or donate to charities they trust. The practical implications of this are that charities seeking to enhance their volunteer and donation base should pay attention to their marketing, reputation and disclosure activities, as well as to doing good work on an ongoing basis in the community. Theoretically, the implications are that transparency and reputation do not result directly in donations and volunteering, but they do create trust, and it is trust which then leads to donations and volunteering.

The ACA effect: Examining how current affairs programs shape victim understandings and responses to online fraud

In recent years, numerous current affairs stories on online fraud victimisation have been broadcast on Australian television. These stories typically feature highly organised, international ‘sting’ operations, in which alleged offenders are arrested and investigated by law enforcement. These portrayals of police responses influence the expectations that some online fraud victims have about how their individual cases will be handled by law enforcement. Based on interviews with 80 online fraud victims, this article argues that a narrow media portrayal of online fraud by television current affairs programs — termed the ‘ACA effect’ — informs victims’ understandings of online fraud and their responses to it. In particular, current affairs programs influence what victims of online fraud expect from police. The article further demonstrates that current affairs programs present themselves as de facto law enforcement agencies, to which victims who receive an unsatisfactory response from police might turn. Overall, the article highlights the importance of current affairs programs portraying a more realistic image of official responses to online fraud.

Effect of DNA extraction on ageing success in coral trout (Plectropomus leopardus) otoliths

To maximize the information commonly collected from otoliths, the effect of DNA extraction on the estimation of age with otoliths was evaluated by comparing sagittal otolith samples from common coral trout (Plectropomus leopardus) for clarity and ageing discrepancies in DNA-extracted and untreated control otoliths. The DNA extraction process had no significant effect, indicating that archived otoliths can be used as a source of DNA while retaining their utility for age estimation.