Effects of soluble dietary cellulose on specific growth rate, survival and digestive enzyme activities in three freshwater crayfish (Cherax) species

Three native freshwater crayfish Cherax species are farmed in Australia namely; Redclaw (Cherax quadricarinatus), Marron (C. tenuimanus), and Yabby (C. destructor). Lack of appropriate data on specific nutrient requirements for each of these species, however, has constrained development of specific formulated diets and hence current use of over-formulated feeds or expensive marine shrimp feeds, limit their profitability. A number of studies have investigated nutritional requirements in redclaw that have focused on replacing expensive fish meal in formulated feeds with non-protein, less expensive substitutes including plant based ingredients. Confirmation that freshwater crayfish possess endogenous cellulase genes, suggests their potential ability to utilize complex carbohydrates like cellulose as nutrient sources in their diet. To date, studies have been limited to only C. quadricarinatus and C. destructor and no studies have compared the relative ability of each species to utilize soluble cellulose in their diets. Individual feeding trials of late-juveniles of each species were conducted separately in an automated recirculating culture system over 12 week cycles. Animals were fed either a test diet (TD) that contained 20% soluble cellulose or a reference diet (RD) substituted with the same amount of corn starch. Water temperature, conductivity and pH were maintained at constant and optimum levels for each species. Animals were fed at 3% of their body weight twice daily and wet body weight was recorded bi-weekly. At the end of experiment, all animals were harvested, measured and midgut gland extracts assayed for alpha-amylase, total protease and cellulase activity levels. After the trial period, redclaw fed with RD showed significantly higher (p<0.05) specific growth rate (SGR) compare with animals fed the TD while SGR of marron and yabby fed the two diets were not significantly different (p<0.05). Cellulase expression levels in redclaw were not significantly different between diets. Marron and yabby showed significantly higher cellulase activity when fed the RD. Amylase and protease activity in all three species were significantly higher in the animals fed with RD (Table 1). These results indicate that test animals of all species can utilize starch better than dietary soluble cellulose in their diet and inclusion of 20% soluble cellulose in diets does not appear to have any significant negative effect on their growth rate but survival was impacted in C. quadricarinatus while not in C. tenuimanus or C. destructor.

Effects of soluble dietary cellulose on specific growth rate, survival and digestive enzyme activities in three freshwater crayfish (Cherax) species

The current study evaluated the effect of soluble dietary cellulose on growth, survival and digestive enzyme activity in three endemic, Australian freshwater crayfish species (redclaw: Cherax quadricarinatus, marron: C. tenuimanus, yabby: C. destructor). Separate individual feeding trials were conducted for late-stage juveniles from each species in an automated recirculating freshwater, culture system. Animals were fed either a test diet (TD) that contained 20% soluble cellulose or a reference diet (RD) substituted with the same amount of corn starch, over a 12 week period. Redclaw fed with RD showed significantly higher (p<0.05) specific growth rates (SGR) compared with animals fed the TD, while SGR of marron and yabby fed the two diets were not significantly different. Expressed cellulase activity levels in redclaw were not significantly different between diets. Marron and yabby showed significantly higher cellulase activity when fed the RD (p<0.05). Amylase and protease activity in all three species were significantly higher in the animals fed with RD (p<0.05). These results indicate that test animals of all three species appear to utilize starch more efficiently than soluble dietary cellulose in their diet. The inclusion of 20% soluble cellulose in diets did not appear, however, to have a significant negative effect on growth rates.

Feeding attitudes, practices and traditional dietary beliefs of Chinese mothers with young children in Australia : a mixed methods study

Background and Objectives Obesity and some dietary related diseases are emerging health problems among Chinese immigrants and their children in developed countries. These health problems are closely linked to eating habits, which are established in the early years of life. Young children’s eating habits are likely to persist into later childhood and youth. Family environment and parental feeding practices have a strong effect on young children’s eating habits. Little information is available on the early feeding practices of Chinese mothers in Australia. The aim of this study was to understand the dietary beliefs, feeding attitudes and practices of Chinese mothers with young children who were recent immigrants to Australia. Methods Using a sequential explanatory design, this mixed methods study consisted of two distinct phases. Phase 1 (quantitative): 254 Chinese immigrant mothers of children aged 12 to 59 months completed a cross-sectional survey. The psychometric properties and factor structure of a Chinese version of the Child Feeding Questionnaire (CFQ, by Birch et al. 2001) were assessed and used to measure specific maternal feeding attitudes and controlling feeding practices. Other questions were developed from the literature and used to explore maternal traditional dietary beliefs and feeding practices related to their beliefs, perceptions of picky eating in children and a range of socioeconomic and acculturation factors. Phase 2 (qualitative): 21 mothers took part in a follow-up telephone interview to assist in explaining and interpreting some significant findings obtained in the first phase. Results Chinese mothers held strong traditional dietary beliefs and fed their children according to these beliefs. However, children’s consumption of non-core foods was high. Both traditional Chinese and Australian style foods were consumed by their children. Confirmatory factor analysis revealed that the original 7-factor model of the CFQ provided an acceptable fit to the data with minor modification. However, an alternative model with eight constructs in which two items related to using food rewards were separated from the original restriction construct, not only provided an acceptable fit to the data, but also improved the conceptual clarity of the constructs. The latter model included 24 items loading onto the following eight constructs: restriction, pressure to eat, monitoring, use of food rewards, perceived responsibility, perception of own weight, perception of child’s weight, and concern about child becoming overweight. The internal consistency of the constructs was acceptable or desirable (Cronbach’s α = .60 - .93). Mothers reported low levels of concern about their child overeating or becoming overweight, but high levels of controlling feeding practices: restriction, monitoring, pressure to eat and use of food rewards. More than one quarter of mothers misinterpreted their child’s weight status (based on mothers’ self-reported data). In addition, mothers’ controlling feeding practices independently predicted half of the variance and explained 16% of the variance in child weight status: pressuring the child to eat was negatively associated with child weight status (β = -0.30, p < .01) and using food rewards was positively associated with child weight status (β = 0.20, p < .05) after adjusting for maternal and child covariates. Monitoring and restriction were not associated with child weight status. Mothers’ perceptions of their child’s weight were positively associated with child weight status (β = 0.33, p < .01). Moreover, mothers reported that they mostly decided what (65%) and how much (80%) food their child ate. Mothers who decided what food their child ate were more likely to monitor (β = -0.17, p < .05) and restrict (β = -0.17, p < .05) their child’s food consumption. Mothers who let their child decide how much food their child ate were less likely to pressure their child to eat (β = -0.38, p < .01) and use food rewards (β = -0.24, p < .01). Mothers’ perceptions of picky eating behaviour were positively associated with their use of pressure (β = 0.21, p < .01) and negatively associated with monitoring (β = -0.16, p < .05) and perceptions of their child’s weight status (β = -0.13, p < .05). Qualitative data showed that pressuring to eat, monitoring and restriction of the child’s food consumption were common practices among these mothers. However, mothers stated that their motivation for monitoring and restricting was to ensure the child’s general health. Mothers’ understandings of picky eating behaviour in their children were consistent with the literature and they reported multiple feeding strategies to deal with it. Conclusion Chinese immigrant mothers demonstrated strong traditional dietary beliefs, a low level of concern for child weight, misperceptions of child weight status, and a high overall level of control in child feeding in this study. The Chinese version of the CFQ, which consists of eight constructs and distinguishes between the constructs using food rewards and restriction, is an appropriate instrument to assess feeding attitudes and controlling feeding practices among Chinese immigrant mothers of young children in Australia. Mothers’ feeding attitudes and practices were associated with children’s weight status and mothers’ perceptions of picky eating behaviour in children after adjusting for a range of socio-demographic maternal and child characteristics. Monitoring and restriction of children’s food consumption according to food selection may be positive feeding practices, whereas pressuring to eat and using food rewards appeared to be negative feeding practices in this study. In addition, the results suggest that these young children have high exposure to energy-dense, nutrient-poor food. There is a need to develop and implement nutrition interventions to improve maternal feeding practices and the dietary quality among children of Chinese immigrant mothers in Australia.

Population structure and patterns of genetic variation in a pearl oyster (Pinctada radiata) native to the Arabian Gulf

The study assessed natural levels and patterns of genetic variation in Arabian Gulf populations of a native pearl oyster to define wild population structure considering potential intrinsic and extrinsic factors that could influence any wild structure detected. The study was also the first attempt to develop microsatellite markers and to generate a genome survey sequence (GSS) dataset for the target species using next generation sequencing technology. The partial genome dataset generated has potential biotechnological applications and for pearl oyster farming in the future.

Sharing news, making sense, saying thanks : patterns of talk on twitter during the Queensland floods

This paper examines the discursive aspects of Twitter communication during the floods in the summer of 2010–2011 in Queensland, Australia. Using a representative sample of communication associated with the #qldfloods hashtag on Twitter, we coded and analysed the patterns of communication. We focus on key phenomena in the use of social media in crisis communication: communal sense- making practices, the negotiation of participant roles, and digital convergence around shared events. Social media is used both as a crisis communication and emergency management tool, as well as a space for participants to engage in emotional exchanges and communication of distress.

Quantitative and qualitative changes in gene expression patterns characterize the activity of plaques in multiple sclerosis

Multiple sclerosis (MS) is a complex autoimmune disorder of the CNS with both genetic and environmental contributing factors. Clinical symptoms are broadly characterized by initial onset, and progressive debilitating neurological impairment. In this study, RNA from MS chronic active and MS acute lesions was extracted, and compared with patient matched normal white matter by fluorescent cDNA microarray hybridization analysis. This resulted in the identification of 139 genes that were differentially regulated in MS plaque tissue compared to normal tissue. Of these, 69 genes showed a common pattern of expression in the chronic active and acute plaque tissues investigated (Pvalue<0.0001, ρ=0.73, by Spearman's ρ analysis); while 70 transcripts were uniquely differentially expressed (≥1.5-fold) in either acute or chronic active tissues. These results included known markers of MS such as the myelin basic protein (MBP) and glutathione S-transferase (GST) M1, nerve growth factors, such as nerve injury-induced protein 1 (NINJ1), X-ray and excision DNA repair factors (XRCC9 and ERCC5) and X-linked genes such as the ribosomal protein, RPS4X. Primers were then designed for seven array-selected genes, including transferrin (TF), superoxide dismutase 1 (SOD1), glutathione peroxidase 1 (GPX1), GSTP1, crystallin, alpha-B (CRYAB), phosphomannomutase 1 (PMM1) and tubulin β-5 (TBB5), and real time quantitative (Q)-PCR analysis was performed. The results of comparative Q-PCR analysis correlated significantly with those obtained by array analysis (r=0.75, Pvalue<0.01, by Pearson's bivariate correlation). Both chronic active and acute plaques shared the majority of factors identified suggesting that quantitative, rather than gross qualitative differences in gene expression pattern may define the progression from acute to chronic active plaques in MS.

Isoenergetic replacement of dietary saturated with monounsaturated fat via macadamia nuts enhances endothelial function in overweight subjects

Background & aims: - Excess adiposity (overweight) is one of numerous risk factors for cardiometabolic disease. Most risk reduction strategies for overweight rely on weight loss through dietary energy restriction. However, since the evidence base for long-term successful weight loss interventions is scant, it is important to identify strategies for risk reduction independent of weight loss. The aim of this study was to compare the effects of isoenergetic substitution of dietary saturated fat (SFA) with monounsaturated fat (MUFA) via macadamia nuts on coronary risk compared to usual diet in overweight adults. Methods: - A randomised controlled trial design, maintaining usual energy intake, but manipulating dietary lipid profile in a group of 64 (54 female, 10 male) overweight (BMI > 25), otherwise healthy, subjects. For the intervention group, energy intakes of usual (baseline) diets were calculated from multiple 3 day diet diaries, and SFA was replaced with MUFA (target: 50%E from fat as MUFA) by altering dietary SFA sources and adding macadamia nuts to the diet. Both control and intervention groups received advice on national guidelines for physical activity and adhered to the same protocol for diet diary record keeping and trial consultations. Anthropometric and clinical measures were taken at baseline and at 10 weeks. Results: A significant increase in brachial artery flow-mediated dilation (p < 0.05) was seen in the monounsaturated diet group at week 10 compared to baseline. This corresponded to significant decreases in waist circumference, total cholesterol (p < 0.05), plasma leptin and ICAM-1 (p < 0.01). Conclusions: - In patient subgroups where adherence to dietary energy-reduction is poor, isoenergetic interventions may improve endothelial function and other coronary risk factors without changes in body weight. This trial was registered with the Australia New Zealand Clinical Trial Registry (ACTRN12607000106437).

A systematic review of baseline psychosocial characterisation in dietary randomised controlled trials for weight loss

BACKGROUND/OBJECTIVE: To investigate the extent of baseline psychosocial characterisation of subjects in published dietary randomised controlled trials (RCTs) for weight loss. SUBJECTS/METHODS: Systematic review of adequately sized (nX10) RCTs comprising X1 diet-alone arm for weight loss were included for this systematic review. More specifically, trials included overweight (body mass index 425 kg/m2) adults, were of duration X8 weeks and had body weight as the primary outcome. Exclusion criteria included specific psychological intervention (for example, Cognitive Behaviour Therapy (CBT)), use of web-based tools, use of supplements, liquid diets, replacement meals and very-low calorie diets. Physical activity intervention was restricted to general exercise only (not supervised or prescribed, for example, VO2 maximum level). RESULTS: Of 176 weight-loss RCTs published during 2008–2010, 15 met selection criteria and were assessed for reported psychological characterisation of subjects. All studies reported standard characterisation of clinical and biochemical characteristics of subjects. Eleven studies reported no psychological attributes of subjects (three of these did exclude those taking psychoactive medication). Three studies collected data on particular aspects of psychology related to specific research objectives (figure scale rating, satiety and quality-of-life). Only one study provided a comprehensive background on psychological attributes of subjects. CONCLUSION: Better characterisation in behaviour-change interventions will reduce potential confounding and enhance generalisability of such studies.

Animated Kolam Patterns

The brief for the creative work was to produce a digital backdrop that would be projected behind and enhance a dance performance. The animation needed to display a static kolam pattern that would then dissolve at a choreographed point in the performance. The dissolving mimics the fragmentation that occurs to physical kolam patterns throughout the day as people interact with the drawings. The final animated work was incorporated into Vanessa Mafe-Keane’s performance titled “Paired Back” performed at the Judith Wright Centre, Brisbane 2013 as part of “Dance. Indie Dance. Through the use of motion capture technology the process of dissolving the pattern is a direct result of the performer’s movements allowing visual and temporal connection between motion of performer and digital graphic to be observed. This creative work presented an opportunity to expand upon experiments conducted in the production of experimental visual forms undertaken at QUT using the Xsens MVN Inertial Motion Capture System. The project took on the form of an investigation into practice with a focus on the additional complexities of capturing, then applying multiple data sources into the production of animated visuals along with bringing to light the considerations taken into account when producing this type of generative art work for live performance. The reported outcomes from this investigation have contributed to a larger study on the use of motion capture in the generative arts, furthering the understanding of and generating theories on practice.

Personal exposure to ultrafine particles : the influence of time-activity patterns

Exposure to ultrafine particles (UFPs) is deemed to be a major risk affecting human health. Therefore, airborne particle studies were performed in the recent years to evaluate the most critical micro-environments, as well as identifying the main UFP sources. Nonetheless, in order to properly evaluate the UFP exposure, personal monitoring is required as the only way to relate particle exposure levels to the activities performed and micro-environments visited. To this purpose, in the present work, the results of experimental analysis aimed at showing the effect of the time-activity patterns on UFP personal exposure are reported. In particular, 24 non-smoking couples (12 during winter and summer time, respectively), comprised of a man who worked full-time and a woman who was a homemaker, were analyzed using personal particle counter and GPS monitors. Each couple was investigated for a 48-h period, during which they also filled out a diary reporting the daily activities performed. Time activity patterns, particle number concentration exposure and the related dose received by the participants, in terms of particle alveolar-deposited surface area, were measured. The average exposure to particle number concentration was higher for women during both summer and winter (Summer: women 1.8×104 part. cm-3; men 9.2×103 part. cm-3; Winter: women 2.9×104 part. cm-3; men 1.3×104 part. cm-3), which was likely due to the time spent undertaking cooking activities. Staying indoors after cooking also led to higher alveolar-deposited surface area dose for both women and men during the winter time (9.12×102 and 6.33×102 mm2, respectively), when indoor ventilation was greatly reduced. The effect of cooking activities was also detected in terms of women’s dose intensity (dose per unit time), being 8.6 and 6.6 in winter and summer, respectively. On the contrary, the highest dose intensity activity for men was time spent using transportation (2.8 in both winter and summer).

Accurate pattern prediction of very closely spaced mismatched antennas using measured active element patterns

A method for prediction of the radiation pattern of N strongly coupled antennas with mismatched sources is presented. The method facilitates fast and accurate design of compact arrays. The prediction is based on the measured N-port S parameters of the coupled antennas and the N active element patterns measured in a 50 ω environment. By introducing equivalent power sources, the radiation pattern with excitation by sources with arbitrary impedances and various decoupling and matching networks (DMN) can be accurately predicted without the need for additional measurements. Two experiments were carried out for verification: pattern prediction for parasitic antennas with different loads and for antennas with DMN. The difference between measured and predicted patterns was within 1 to 2 dB.

Capping them off! Exploring and explaining the patterns in undergraduate capstone subjects in Australian business schools

Universities are increasingly offering capstone subjects as part of curricula to prepare final year undergraduates for employment through consolidating and integrating their knowledge and skills while bridging the gap between academic learning and professional work. This study investigates capstone subjects offered by Australian business schools, drawing on national survey data collected in 2010-2011, complemented by interviews with associate deans teaching and learning instrumental in course and curricula design. Findings indicate the sector-wide use of capstone subjects in business disciplines, diversity in the patterns of offerings, and instances where subjects labelled as capstones do not meet the definition of capstones. We argue that these features are explained by a range of historic and strategic factors, such as the ad hoc development of subjects and a lack of understanding of the features of capstones. The findings of this paper inform the debate on the design, development, value and use of capstone subjects identifying the implications for staff development and knowledge management in higher education.

Quantitative Approaches to Comparing Communication Patterns on Twitter

To date, available literature mainly discusses Twitter activity patterns in the context of individual case studies, while comparative research on a large number of communicative events, their dynamics and patterns is missing. By conducting a comparative study of more than forty different cases (covering topics such as elections, natural disasters, corporate crises, and televised events) we identify a number of distinct types of discussion which can be observed on Twitter. Drawing on a range of communicative metrics, we show that thematic and contextual factors influence the usage of different communicative tools available to Twitter users, such as original tweets, @replies, retweets, and URLs. Based on this first analysis of the overall metrics of Twitter discussions, we also demonstrate stable patterns in the use of Twitter in the context of major topics and events.

An exploratory study to evaluate whether medical nutrition therapy can improve dietary intake in hospital patients who eat poorly

Background and aims The Australasian Nutrition Care Day Survey (ANCDS) reported two-in-five patients consume ≤50% of the offered food in Australian and New Zealand hospitals. After controlling for confounders (nutritional status, age, disease type and severity), the ANCDS also established an independent association between poor food intake and increased in-hospital mortality. This study aimed to evaluate if medical nutrition therapy (MNT) could improve dietary intake in hospital patients eating poorly. Methods An exploratory pilot study was conducted in the respiratory, neurology and orthopaedic wards of an Australian hospital. At baseline, percentage food intake (0%, 25%, 50%, 75%, and 100%) was evaluated for each main meal and snack for a 24-hour period in patients hospitalised for ≥2 days and not under dietetic review. Patients consuming ≤50% of offered meals due to nutrition-impact symptoms were referred to ward dietitians for MNT. Food intake was re-evaluated on the seventh day following recruitment (post-MNT). Results 184 patients were observed over four weeks; 32 patients were referred for MNT. Although baseline and post-MNT data for 20 participants (68±17years, 65% females) indicated a significant increase in median energy and protein intake post-MNT (3600kJ/day, 40g/day) versus baseline (2250kJ/day, 25g/day) (p<0.05), the increased intake met only 50% of dietary requirements. Persistent nutrition impact symptoms affected intake. Conclusion In this pilot study whilst dietary intake improved, it remained inadequate to meet participants’ estimated requirements due to ongoing nutrition-impact symptoms. Appropriate medical management and early enteral feeding could be a possible solution for such patients.