Genetic sex determination systems are generally based on the presence of differentiated sex chromosomes. Birds have a ZZ/ZW sex chromosome system in which males are ZZ and females ZW, whereas mammals have an XX/XY system with males being XY and females XX. Monotremes have an extraordinary sex chromosome system that consists of multiple sex chromosomes: 5X5Y in platypus and 5X4Y in echidna. Intriguingly, the monotreme sex chromosomes show extensive homology to the bird ZW and not to the therian XY. However, sex determination in monotremes is still a mystery; the Y-specific Sry gene that triggers male sex determination in therian mammals is absent and so far very few genes have been identified on Y chromosomes in monotremes. To gain more insights into the gene content of Y-chromosomes and to identify potential sex determination genes in the platypus a collaborative large scale transcriptomic approach led to the identification of new male specific genes including the anti-Muellerian hormone AMH that I mapped to Y₅, this makes Amhy an exciting new candidate for sex determination in monotremes. Platypus chromosome 6 is largely homologous to the therian X and therefore it represents the therian proto sex chromosome. In addition, this autosome features a large heteromorphic nucleolus organizer region (NOR) and associates with the sex chromosomes during male meiosis (Casey and Daish personal communication). I investigated chromosome 6 heteromorphism in both sexes and found a number of sex-specific characteristics related to the extent of the NOR heteromorphism...

In this thesis, we investigate the optimal experimental design of some common biological experiments. The theory of optimal experimental design is a statistical tool that allows us to determine the optimal experimental protocol to gain the most information about a particular process, given constraints on resources. We focus on determining the optimal design for experiments where the underlying model is a Markov chain | a particularly useful stochastic model. Markov chains are commonly used to represent a range of biological systems, for example: the evolution and spread of populations and disease, competition between species, and evolutionary genetics. There has been little research into the optimal experimental design of systems where the underlying process is modelled as a Markov chain, which is surprising given their suitability for representing the random behaviour of many natural processes. While the first paper to consider the optimal experimental design of a system where the underlying process was modelled as a Markov chain was published in the mid 1980's, this research area has only recently started to receive significant attention. Current methods of evaluating the optimal experimental design within a Bayesian framework can be computationally inefficient...

In recent years, implant dentistry has become a routine part of many general dental practices in Australia. However, there is little information regarding its prevalence as well as the extent and nature of its practice. This investigation aims to address the paucity of information in this area. Additionally, data concerning general dental practitioners (GDPs) will be compared with that for dental specialists to reveal the degree of conformity between the two groups in their practice of implant dentistry. The results of this research may also be of assistance in the development of educational programs in this field. Electronic surveys on the practice of implant dentistry were designed using SurveyMonkey™ and delivered along with a participation invitation to the following professional bodies: all seven State/Territory branches of the Australian Dental Association (ADA), the Australian and New Zealand Academy of Periodontists (ANZAP), the Australian and New Zealand Academy of Oral and Maxillofacial Surgeons (ANZAOMS), and prosthodontist members of the Australian Prosthodontic Society (APS). After examining the surveys for approval, all above professional organisations agreed to participate by inviting their respective members to complete the surveys online via SurveyMonkey™. The same program was used to analyse the responses while preserving the anonymity of the respondents. The initial response rates were 7.61% (n = 801) for GDPs...

Disparities in access to dental services have been reported for particular groups of Australians. Consequently, these groups suffer a greater burden of oral disease when compared with the general population. The reasons why dentists do not undertake and/or sustain working with disadvantaged patients are well known but not so well known is what drives those who do. This project aims to better understand the characteristics of dentists whose practice orientation is focused on care for disadvantaged groups. This will supplement existing knowledge of dentists’ career decision making, allow more targeted recruitment of dental applicants, and inform admissions committees and dental educators about how best to prepare students with the skills, attributes and experiences necessary to serve all Australians. The aim of this research project was to explore the characteristics, values, beliefs, and motivations of dentists who work with disadvantaged patients and compare the findings with those who treat mainly general patients. A sequential mixed-method study design was undertaken. Dentists who worked with underserved groups were purposefully recruited using the ‘snowballing’ technique and interviewed. Thematic analysis of the transcripts followed; the findings of which formed the basis of the questionnaire sent to a random sample of registered dentists in Australia. Univariate...

Microalgae are generally considered as a promising biomass source for applications including production of advanced biofuels, chemicals, wastewater treatments, various organic substances or a combination of any of the above. The advantages of microalgae includes faster growth rates than terrestrial plants, ability to use non-arable land for mass production, and their ability to grow in poor quality water, as well as their ability to remove pollutants from wastewater streams. However, one of the major challenges of microalgae for commercialisation to is its economic downstream production and conversion to biofuels and chemicals. When harvested, microalgae contains up to ~90% water content, thus economic conversion of high moisture content biomass to valuable products such as biofuels remains a challenge. Hydrothermal liquefaction (HTL) involves processing of high moisture content biomass in hot compressed water, avoiding the drying step for biomass feedstocks. Therefore HTL is advantageous as it avoids the energy intensive drying process in contrast to processes that involve drying of biomass prior to processing into biofuels. HTL products comprise biocrude, solid residues, aqueous and gas phases. The primary product biocrude is upgradable to liquid transportation fuels. The aqueous phase contains essential nutrients that could be recycled to microalgae cultivation ponds. The gas phase contains about 98mol% carbon dioxide (CO₂) and 2mol% hydrocarbon gases. The gas phase can also be directly recycled to the microalgae cultivation ponds for pH control and supply of CO₂...

Loredana G. Marcu, Eva Bezak, Iuliana Toma-Dasu, and Alexandru Dasu; Editorial, abstract not included.

BACKGROUND: Wine fermentation is a harsh ecological niche to which wine yeast are well adapted. The initial high osmotic pressure and acidity of grape juice is followed by nutrient depletion and increasing concentrations of ethanol as the fermentation progresses. Yeast's adaptation to these and many other environmental stresses, enables successful completion of high-sugar fermentations. Earlier transcriptomic and growth studies have tentatively identified genes important for high-sugar fermentation. Whilst useful, such studies did not consider extended growth (>5 days) in a temporally dynamic multi-stressor environment such as that found in many industrial fermentation processes. Here, we identify genes whose deletion has minimal or no effect on growth, but results in failure to achieve timely completion of the fermentation of a chemically defined grape juice with 200 g L-1 total sugar. RESULTS: Micro- and laboratory-scale experimental fermentations were conducted to identify 72 clones from ~5,100 homozygous diploid single-gene yeast deletants, which exhibited protracted fermentation in a high-sugar medium. Another 21 clones (related by gene function, but initially eliminated from the screen because of possible growth defects) were also included. Clustering and numerical enrichment of genes annotated to specific Gene Ontology (GO) terms highlighted the vacuole's role in ion homeostasis and pH regulation...

Martin L Ashdown, Brendon J Coventry, Derek Abbott

Precipitation and seasonal water level fluctuations mostly add to the problem of soil and groundwater contamination and lead to pollution of capillary fringe layer and exacerbation of groundwater contamination. At the Tehran Oil Refining Company (TORC), with critical problem of soil and groundwater pollution, finding a suitable remediation method has been a big concern. As bioremediation is one of the most economically and technically attractive decontamination methods, it was chosen for preliminary study to solve this problem. For simulation of the region, soil column treatment method by using oil habituated indigenous microorganisms of the area was selected. The main purpose was assessing the suitability of bioremediation method in the target area for treatment of capillary fringe layer. Two columns (one as treatment column and the other as a control) were designed and the variation of different parameters including dissolved oxygen (DO), pH, the number of viable and active microorganisms (CFU/mL), and biodegradation rate during 30 working days were recorded. The experiments showed that a major part of degrading microorganisms were facultative anaerobic. pH was not an inhibiting factor and the number of active microorganisms was increasing during aeration time. The results of solvent extraction method also revealed that during 30 days...

The incidence of severe postpartum hemorrhage (PPH) is increasing. Regional variation may be attributed to variation in provision of care, and as such contribute to this increasing incidence. We assessed reasons for regional variation in severe PPH in the Netherlands.We used the Netherlands Perinatal Registry and the Dutch Maternal Mortality Committee to study severe PPH incidences (defined as blood loss ≥ 1000 mL) across both regions and neighborhoods of cities among all deliveries between 2000 and 2008. We first calculated crude incidences. We then used logistic multilevel regression analyses, with hospital or midwife practice as second level to explore further reasons for the regional variation.We analyzed 1599867 deliveries in which the incidence of severe PPH was 4.5%. Crude incidences of severe PPH varied with factor three between regions while between neighborhoods variation was even larger. We could not explain regional variation by maternal characteristics (age, parity, ethnicity, socioeconomic status), pregnancy characteristics (singleton, gestational age, birth weight, pre-eclampsia, perinatal death), medical interventions (induction of labor, mode of delivery, perineal laceration, placental removal) and health care setting.In a nationwide study in The Netherlands...

This paper proposes a new image signature, called Compass Rose, which is particularly suited to optical flow computation. It is differentiable, fast to compute, and robust to additive illumination changes, translation, and fast rotation. We design a sparse flow computation system based on the invariance of the Compass Rose signatures. This is then extended to dense motion estimation by the addition of an optional diffusion step. Quantitative testing on several benchmark sequences shows the Compass Rose attains higher accuracy than the traditional flow signatures under a range of conditions. Finally, we demonstrate its application to human motion estimation, which is challenging for optical flow methods due to fast limb rotation.; Yan Niu, Anthony Dick, and Michael Brooks

INTRODUCTION: In this study, we aimed to evaluate whether fasting plasma citrulline concentration predicts subsequent glucose absorption in critically ill patients. METHODS: In a prospective observational study involving 15 healthy and 20 critically ill subjects, fasting plasma citrulline concentrations were assayed in blood samples immediately prior to the administration of a liquid test meal (1 kcal/ml; containing 3 g of 3-O-methylglucose (3-OMG)) that was infused directly into the small intestine. Serum 3-OMG concentrations were measured over the following 4 hours, with the area under the 3-OMG concentration curve (AUC) calculated as an index of glucose absorption. RESULTS: The groups were well matched in terms of age, sex and body mass index (BMI) (healthy subjects versus patients, mean (range) values: age, 47 (18 to 88) versus 49 (21 to 77) years; sex ratio, 60% versus 80% male; BMI, 25.2 (18.8 to 30.0) versus 25.5 (19.4 to 32.2) kg/m(2)). Compared to the healthy subjects, patients who were critically ill had reduced fasting citrulline concentration (26.5 (13.9 to 43.0) versus 15.2 (5.7 to 28.6) μmol/L; P < 0.01) and glucose absorption (3-OMG AUC, 79.7 (28.6 to 117.8) versus 61.0 (4.5 to 97.1) mmol/L/240 min; P = 0.05). There was no relationship between fasting citrulline concentration and subsequent glucose absorption (r = 0.28; P = 0.12). CONCLUSIONS: Whereas both plasma citrulline concentrations and glucose absorption were reduced in critical illness...

The contemporary default materials for multi-storey buildings – namely concrete and steel – are all significant generators of carbon and the use of timber products provides a technically, economically and environmentally viable alternative. In particular, timber's sustainability can drive increased use and subsequent evolution of the Blue economy as a new economic model. National research to date, however, indicates a resistance to the uptake of timber technologies in Australia. To investigate this further, a preliminary study involving a convenience sample of 15 experts was conducted to identify the main barriers involved in the use of timber frames in multi-storey buildings. A closed-ended questionnaire survey involving 74 experienced construction industry participants was then undertaken to rate the relative importance of the barriers. The survey confirmed the most significant barriers to be a perceived increase in maintenance costs and fire risk, together with a limited awareness of the emerging timber technologies available. It is expected that the results will benefit government and the timber industry, contributing to environmental improvement by developing strategies to increase the use of timber technologies in multi-storey buildings by countering perceived barriers in the Australian context.; Bo Xia...

Frederik J. Hermans, Brenda M. Kazemier, Ben W. Mol; Letter to the Editor

Abstract not available; Gunther G. Andersson, Vladimir B. Golovko, Jason F. Alvino, Trystan Bennett, Oliver Wrede, Sol M. Mejia, Hassan S. Al Qahtani, Rohul Adnan, Nathaniel Gunby, David P. Anderson, and Gregory F. Metha

Abstract not available; S. M. S. Liem, G. J. van Baaren, F. M. C. Delemarre, I. M. Evers, G. Kleiverda, A. J. van Loon, J. Langenveld, N. Schuitemaker, J. M. Sikkema, B. C. Opmeer, M. G. van Pampus, B. W. J. Mol and D. J. Bekedam; Article first published online: 7 AUG 2014

INTRODUCTION: In the developed world, preterm birth is in quantity and in severity the most important issue in obstetric care. Adverse neonatal outcome is strongly related to gestational age at delivery. Since the pathophysiological mechanism of preterm birth is not yet completely unraveled, the development of successful preventive strategies is hampered. When preterm labor is actually threatening, current pharmacological therapies focus on inhibition of preterm contractions. This allows for transportation of the mother to a center with a neonatal intensive care unit and administration of corticosteroids to enhance fetal lung maturation. Globally, however, large practice variation exists. AREAS COVERED: The aim of this review is to provide an overview of current pharmacological therapies for preterm labor. EXPERT OPINION: For the initial tocolysis, the use of atosiban or nifedipine for 48 h is recommended based on the largest effectiveness and most favorable side effect profile. However, since data that convincingly indicate the beneficial effect of tocolytics on neonatal outcome are lacking, it might well be that tocolytics are ineffective. The role of progesterone in treatment of acute tocolysis is limited, but it might play a role in the prevention of preterm labor or as sensitizer for other tocolytic agents.; Elvira OG van Vliet...

A rainbow-ladder truncation of QCD’s Dyson-Schwinger equations is used to calculate ρ- and ϕ-meson valence-quark (twist-two parton) distribution amplitudes (PDAs) via a light-front projection of their Bethe-Salpeter wave functions, which possess S- and D-wave components of comparable size in the meson rest frame. All computed PDAs are broad concave functions, whose dilation with respect to the asymptotic distribution is an expression of dynamical chiral symmetry breaking. The PDAs can be used to define an ordering of valence-quark light-front spatial extent within mesons: this size is smallest within the pion and increases through the ⊥ polarization to the ∥ polarization of the vector mesons; effects associated with the breaking of SU(3)-flavor symmetry are significantly smaller than those associated with altering the polarization of vector mesons. Notably, the predicted pointwise behavior of the ρ-meson PDAs is in quantitative agreement with that inferred recently via an analysis of diffractive vector-meson photoproduction experiments.; Fei Gao, Lei Chang, Yu-Xin Liu, Craig D. Roberts, and Sebastian M. Schmidt

OBJECTIVE: In an unselected group of women with signs of preterm labour, maintenance tocolysis is not effective in the prevention of preterm birth and does not improve neonatal outcome. Among women with signs of preterm labour, those who are fetal fibronectin positive have an increased risk of preterm birth. We investigated whether maintenance tocolysis with nifedipine would delay delivery and improve neonatal outcome in women with threatened preterm labour and a positive fetal fibronectin status. STUDY DESIGN: Women with a singleton pregnancy in threatened preterm labour (24(+0) to 33(+6)  weeks) with a positive fetal fibronectin test were randomised to nifedipine or placebo. Study medication was continued until 36 completed weeks' gestation. The primary endpoint was prolongation of pregnancy of seven days. Secondary endpoints were gestational age at delivery and length of NICU admission. RESULTS: Of the 60 participants, 29 received nifedipine and 31 placebo. Prolongation of pregnancy by >7 days occurred in 22/29 (76%) in the nifedipine group and 25/31 (81%) in the placebo group (relative risks, RR 0.94 [0.72-1.2]). Gestational age at delivery was 36.1 ± 5.1 weeks for nifedipine and 36.8 ± 3.6 weeks for placebo (P = 0.027). Length of NICU admission [median (interquartile ranges...

The geotechnical conditions at Coghlan Road, Outer Harbor, SA comprise dredged fill over estuarine clays, sands and peat of the St. Kilda Formation. All these soil layers are soft, saturated, and have the property of undergoing large settlements under load. The development of the site into a large export facility involving heavy container handling and storage for the Hardy Wine Company therefore required special earthworks procedures. This paper outlines the nature of the soil conditions at the site, the method of ground treatment used to preconsolidate the soft soils, and the results of settlement readings extending over time periods up to 9 months. The results of predictions of the settlement over a 15-year time period are outlined. Pavement configurations for the heavy container and truck areas are described. The paper describes how the extent of ground improvement was shown to be sufficient to permit the construction of pavements for heavy container traffic and a slab-on-ground and shallow spread footings for the 20,000 m2 warehouse structure.; Peter W. Mitchell and Brendan Scott