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There is an increasing incidence of overweight/obesity and mental health disorders in young adults and the two conditions often coexist. We aimed to investigate the influence of antenatal and postnatal factors that may underlie this association with a focus on maternal prenatal smoking, socio-economic status and gender. Data from the Western Australian Pregnancy Cohort (Raine) Study (women enrolled 1989–1991) including 1056 offspring aged 20 years (cohort recalled 2010–2012) were analyzed (2015–2016) using multivariable models for associations between offspring depression scores (DASS-21 Depression-scale) and body mass index (BMI), adjusting for pregnancy and early life factors and offspring behaviours. There was a significant positive relationship between offspring depression-score and BMI independent of gender and other psychosocial covariates. There was a significant interaction between maternal prenatal smoking and depression-score (interaction coefficient=0.096; 95% CI: 0.006, 0.19, P=0.037), indicating the relationship between depression-score and BMI differed according to maternal prenatal smoking status. In offspring of maternal prenatal smokers, a positive association between BMI and depression-score (coefficient=0.133; 95% CI: 0.05, 0.21, P=0.001) equated to 1.1 kg/m2 increase in BMI for every 1standard deviation (8 units) increase in depression-score. Substituting low family income during pregnancy for maternal prenatal smoking in the interaction (interaction coefficient=0.091; 95% CI: 0.01, 0.17, P=0.027) showed a positive association between BMI and depression score only among offspring of mothers with a low family income during pregnancy (coefficient=0.118; 95% CI: 0.06, 0.18, P<0.001). There were no significant effects of gender on these associations. Whilst further studies are needed to determine whether these associations are supported in other populations, they suggest potentially important maternal behavioural and socio-economic factors that identify individuals vulnerable to the coexistence of obesity and depression in early adulthood.
Cellulose and hemicellulose are the major structural polysaccharides of plant cell wall. The efficient utilization of these polysaccharides by ruminants is often restricted by the presence of lignin. Cellulose and hemicellulose are hydrolysed by a group of enzymes called cellulases and hemicellulases. The present paper describes the cellulase and hemicellulase assay methods and their potential applications.
Carboxymethyl (CM)-cellulose, Avicel, cellobiose, xylobiose, p-nitrophenyl-p β-D-glucoside (pNPG), p-nitrophenyl-β-D-cellobioside (pNPC), p-nitrophenyl-β-D-xyloside (pNPX) and p-nitrophenyl- α-L-arabinofuranoside (pNPAf) were from Sigma. Birchwood xylan and filter paper are from Carl Roth GmbH and Co., Germany and Whatman International Ltd, UK, respectively. H3P04-Swollen cellulose and 4-O-methyl-α-D-glucuronyl-xylotriose (mGpA-Xyl3) were prepared as described (Wood, 1988; Khandke et al., 1989a).
The genus Acacia Miller is species-rich, and species discrimination is challenging owing to morphological similarities between closely related species. Naming of specimens is particularly difficult in the Middle East, where confusion in taxonomic identification exists within the context of a wider international debate on the generic systematics of Acacia sensu lato. At least five segregate genera for Acacia s.l. have been advocated: Acacia sensu stricto, Vachellia, Senegalia, Acaciella and Mariosousa. Furthermore, identification to species of the only remaining native Acacia s.l. tree in Kuwait is still a matter of controversy. The present study used multilocus chloroplast DNA sequence data analyses following maximum likelihood (ML) and Bayesian approaches to: 1) test the species concepts of Vachellia pachyceras (≡ Acacia pachyceras O.Schwartz) from the Middle East, and Vachellia tortilis (Forssk.) Galasso & Banfi (≡ Acacia tortilis (Forssk.) Hayne) and Vachellia gerrardii (Benth.) P.J.H.Hurter (≡ Acacia gerrardii Benth.) from Kenya, as well as to investigate species divergence times; and 2) identify the only remaining native Acacia s.l. tree in Kuwait (known as the Lonely Tree), as well as other unidentified Acacia s.l. specimens in cultivation. The Bayesian and ML topologies clearly differentiated Vachellia pachyceras, V. tortilis and V. gerrardii, and demonstrated that the three species are distinct. Divergence time estimates using the ML topology suggested that Vachellia gerrardii diverged from a common ancestor no later than the early Pliocene (3.3 Mya), whereas V. pachyceras originated at least 2.0 Mya (Pliocene). The unknown remaining native Acacia s.l. tree in Kuwait and other specimens collected from the nursery were identified as Vachellia pachyceras. These results stress the need to use plastid DNA barcodes complemented by population genetics approaches to address systematic issues in this complex of Acacia s.l. species in the Middle East and the Arabian Peninsula.
Several techniques involving enzymes as alternatives to rumen fluid in in vitro studies have been proposed. However, high cost, ill-defined characterisation and high variation among enzyme preparations and batches have discouraged their use. In addition, most studies have aimed at determining dry matter degradability (DMD) at a fixed time, commonly 48 h. Consequently little information has been published concerning the DM degradation dynamics of forages incubated with enzymes. Therefore the objective of the present study was to compare the ability of a commercial enzyme mixture to describe the fermentation dynamics of two contrasting forages, using the ANKOM in vitro fermentation system (Daisy II, ANKOM Co, USA).
Cellulose and hemicellulose are the major structural carbohydrates present in forages and form between 30 and 60% of the forage component of ruminant diets. The complex network of structural carbohydrates and lignin generally leads to low digestibility and limits the efficient utilisation of forages by ruminants. This situation occurs in both developed and developing countries, and in the latter it is particularly pronounced as much of the forage component is based around the use of crop residues (Owen and Jayasuria, 1989). Because forage costs are significantly lower than those of other dietary ingredients, improving forage quality has been a major objective for many research programmes in both the developed and developing world. Improvements in forage quality have been sort through a number of different strategies. These have included conventional breeding techniques, which have included the integration of mutant genes, leading to the development of Brown Midrib varieties of maize and the use of chemical and biological additives. Enzyme supplements are commonly used to improve the nutritive value of feeds for non ruminants and as silage additives where they have been shown to improve silage fermentation, feed intake and performance. Recent work with ruminants has however focused on the use of enzyme supplements to improve feed efficiency by the use of “direct-fed” fibrolytic enzymes. This strategy involves the application of enzymes to feed at or only hours before feeding. These studies have yielded very variable production responses. For any new technology to be implemented widely, the responses achieved must provide an acceptable level of consistency and predictability. The current paper reviews developments in enzymology, production responses achieved and the effects on nutrient digestion.
A number of fibrolytic enzyme preparations have been shown to increase the rate and extent of fermentation of alfalfa fractions (Colombatto et al., 2000a). However, responses to enzyme addition have been mixed and several factors are believed to be involved. Among these, specific enzyme activities and application rates are very important. The present study examined a commercial enzyme preparation already established as effective, for its ability to increase the rate and extent of in vitro fermentation of alfalfa stems, when applied at different levels.
Treatment of forage with enzyme mixtures can increase rate of degradation in vitro (Colombatto et al., 2000a). However, the complexity of natural forage makes it difficult to determine what fractions are most affected by enzyme treatment. The use of pure substrates (e.g. cellulose and xylan), provides a way of evaluating enzyme mode of action. Therefore, the present study examined the effects of pre-treating avicel and xylan with an enzyme mixture (EM) on a) the reducing sugars produced during treatment before rumen fermentation and b) the gas production profiles during in vitro rumen fermentation using the Reading Pressure Technique (RPT) (Mauricio et al., 1999).
Modern feeding practices often lead to ruminal conditions being sub-optimal for fibre digestion. It has been speculated that fibrolytic enzymes, which usually show optimum activity at pH values below 6.0, may be of benefit when applied to diets of high producing animals. This study used a commercial enzyme mixture (EM), already identified as effective; to investigate its optimum pH range with respect to activity and its impact on the fermentation profiles of pure substrates, under differing pH conditions.
Feed enzymes for ruminants have received considerable attention recently, because of their potential to improve animal performance. However, the commercial preparations available are generally mixtures and are poorly characterised. Furthermore, their role in improving the nutritive value of ruminant feeds is not well understood. Previous work with a commercial enzyme applied at ensiling of maize stover showed a significant decrease in cell wall contents (Altaf et al., 1997). The present study evaluated the enzyme used by Altaf et al. (1997) in terms of a) main enzyme activities; b) ability to hydrolyse feeds at three different pHs and c) HPLC analysis of the products released.
Selected fibrolytic enzyme preparations applied at ensiling have been shown to reduce the fibre contents and to increase the initial rate of in vitro organic matter degradation (OMD) of maize silage (Colombatto et al., 2001). However, there is little information on changes in the fibre content of maize forage during the ensiling process, as affected by enzyme addition. The present study examined the effects of characterised enzyme preparations (Colombatto et al., 2000), derived from mesophilic and thermophilic fungal sources applied at ensiling, on the quality and in vitro rumen degradation characteristics of maize silage, as assessed using the Reading Pressure Technique (RPT, Mauricio et al., 1999).
Considerable research efforts have been directed towards the use of cell wall degrading enzymes as feed additives. However, the factors affecting the response to a certain enzyme preparation are not well understood. A better knowledge of the enzymatic activities present in the preparations and their interaction with a substrate in presence of rumen fluid is needed. The objectives of this study were to characterise the main enzymatic activities of six enzyme preparations and to evaluate them in the presence of rumen fluid, using the in vitro Reading Pressure Technique (RPT).
Epitaxial Ge films are useful as a substrate for high-efficiency solar cell applications. It is possible to grow epitaxial Ge films on low cost, cube textured Ni(001) sheets using CaF2(001) as a buffer layer. Transmission electron microscopy (TEM) analysis indicates that the CaF2(001) lattice has a 45o in-plane rotation relative to the Ni(001) lattice. The in-plane epitaxy relationships are CaF2//Ni and CaF2[
10]//Ni. Energy dispersive spectroscopy (EDS) shows a sharp interface between Ge/CaF2 as well as between CaF2/Ni. Electron backscatter diffraction (EBSD) shows that the Ge(001) film has a large grain size (∼50 μm) with small angle grain boundaries (< 8o). The epitaxial Ge thin film has the potential to be used as a substrate to grow high quality III-V and II-VI semiconductors for optoelectronic applications.
Introduction: The suboptimal management of children’s pain in the emergency department (ED) is well described. Although surveys of physicians show improvements in providing analgesia, institutional audits suggest otherwise. One reason may be patient refusal. Our objectives were to determine the proportion of caregivers that offered analgesia prior to arrival to the ED, accept analgesia in the ED, and identify reasons for withholding analgesia. Our results will inform knowledge translation initiatives to improve analgesic provision to children. Methods: A novel survey was designed to test the hypothesis that a large proportion of caregivers withhold and refuse analgesia. Over a 16-week period across two Canadian paediatric EDs, we surveyed caregivers of children aged 4-17 years with an acutely painful condition (headache, otalgia, sore throat, abdominal pain, or musculoskeletal injury). The primary outcome was the proportion of caregivers who offered analgesia up to 24 hours prior to ED arrival and accepted analgesia in the ED. Results: The response rate was 568/707 (80.3%). The majority of caregivers were female (426/568, 75%), aged 36 years or older (434/568, 76.4%), and had a post-secondary education (448/561, 79.9%). Their children included 320 males and 248 females with a mean age of 10.6 years. Most (514/564, 91.1%) reported being “able to tell when their child was in pain”. On average, children rated their maximal pain at 7.4/10. A total of 382/561 (68.1%) caregivers did not offer any form of analgesia prior to arrival. Common reasons included lack of time (124/561, 22.1%), fear of masking signs and symptoms (74/561, 13.2%) or the seriousness of their child’s condition (72/561, 12.8%), and lack of analgesia at home (71/561, 12.7%). Analgesia was offered to 328/560 (58.6%) children in the ED and 283/328 (72.6%) caregivers accepted. The most common reason for not accepting analgesia was child refusal (20/45, 44.4%). Conclusion: Most caregivers do not offer analgesia to their child prior to arriving in the ED despite high levels of pain and an awareness of it. Despite high rates of acceptance of analgesia in the ED, misconceptions are common. Knowledge translation strategies should dispel caregiver misconceptions, and highlight the impact of pain on children and the importance of analgesia at home.
We compare first-order (refractive) ionospheric effects seen by the MWA with the ionosphere as inferred from GPS data. The first-order ionosphere manifests itself as a bulk position shift of the observed sources across an MWA field of view. These effects can be computed from global ionosphere maps provided by GPS analysis centres, namely the CODE. However, for precision radio astronomy applications, data from local GPS networks needs to be incorporated into ionospheric modelling. For GPS observations, the ionospheric parameters are biased by GPS receiver instrument delays, among other effects, also known as receiver DCBs. The receiver DCBs need to be estimated for any non-CODE GPS station used for ionosphere modelling. In this work, single GPS station-based ionospheric modelling is performed at a time resolution of 10 min. Also the receiver DCBs are estimated for selected Geoscience Australia GPS receivers, located at Murchison Radio Observatory, Yarragadee, Mount Magnet and Wiluna. The ionospheric gradients estimated from GPS are compared with that inferred from MWA. The ionospheric gradients at all the GPS stations show a correlation with the gradients observed with the MWA. The ionosphere estimates obtained using GPS measurements show promise in terms of providing calibration information for the MWA.
The Murchison Widefield Array is a Square Kilometre Array Precursor. The telescope is located at the Murchison Radio–astronomy Observatory in Western Australia. The MWA consists of 4 096 dipoles arranged into 128 dual polarisation aperture arrays forming a connected element interferometer that cross-correlates signals from all 256 inputs. A hybrid approach to the correlation task is employed, with some processing stages being performed by bespoke hardware, based on Field Programmable Gate Arrays, and others by Graphics Processing Units housed in general purpose rack mounted servers. The correlation capability required is approximately 8 tera floating point operations per second. The MWA has commenced operations and the correlator is generating 8.3 TB day−1 of correlation products, that are subsequently transferred 700 km from the MRO to Perth (WA) in real-time for storage and offline processing. In this paper, we outline the correlator design, signal path, and processing elements and present the data format for the internal and external interfaces.
The science cases for incorporating high time resolution capabilities into modern radio telescopes are as numerous as they are compelling. Science targets range from exotic sources such as pulsars, to our Sun, to recently detected possible extragalactic bursts of radio emission, the so-called fast radio bursts (FRBs). Originally conceived purely as an imaging telescope, the initial design of the Murchison Widefield Array (MWA) did not include the ability to access high time and frequency resolution voltage data. However, the flexibility of the MWA’s software correlator allowed an off-the-shelf solution for adding this capability. This paper describes the system that records the 100 μs and 10 kHz resolution voltage data from the MWA. Example science applications, where this capability is critical, are presented, as well as accompanying commissioning results from this mode to demonstrate verification.
We present the results of an approximately 6 100 deg2 104–196 MHz radio sky survey performed with the Murchison Widefield Array during instrument commissioning between 2012 September and 2012 December: the MWACS. The data were taken as meridian drift scans with two different 32-antenna sub-arrays that were available during the commissioning period. The survey covers approximately 20.5 h < RA < 8.5 h, − 58° < Dec < −14°over three frequency bands centred on 119, 150 and 180 MHz, with image resolutions of 6–3 arcmin. The catalogue has 3 arcmin angular resolution and a typical noise level of 40 mJy beam− 1, with reduced sensitivity near the field boundaries and bright sources. We describe the data reduction strategy, based upon mosaicked snapshots, flux density calibration, and source-finding method. We present a catalogue of flux density and spectral index measurements for 14 110 sources, extracted from the mosaic, 1 247 of which are sub-components of complexes of sources.
In the present study, inter- and intrapopulation diversity of five named rice landraces from parts of Odisha state of India representing static and dynamic management was examined using 14 sequence-tagged microsatellite site primer pairs. A total of 64 alleles were detected in ten populations of the five named landraces. The number of alleles ranged from 2 to 7, with an average of 4.57 alleles per locus. Of the 64 alleles, 60 were common and four were rare. Moderate-to-low diversity was observed in the landrace populations, with the number of alleles per population ranging from 16 to 25 and the percentage of polymorphism ranging from 14.29 to 64.29, respectively. The analysis of molecular variance indicated a highest variation of 75.7% among populations within groups (static vs. dynamic). The pairwise estimates of FST revealed very high significant population differentiation, which ranged from 0.68 to 0.89, indicating that the populations share limited genetic diversity among them. However, not many variations were observed in the phenotypes of populations representing static and dynamic management. This shows that adaptations of a population apparently persist over generations, but the underlying genotypes change and new alleles or combinations may arise and increase in frequency at the expense of other alleles that have disappeared. The importance of population biology research for in situ conservation requires both descriptive and hypothesis testing to guide technical improvement and management of landrace populations.
The first direct detection of gravitational waves may be made through observations of pulsars. The principal aim of pulsar timing-array projects being carried out worldwide is to detect ultra-low frequency gravitational waves (f ∼ 10−9–10−8 Hz). Such waves are expected to be caused by coalescing supermassive binary black holes in the cores of merged galaxies. It is also possible that a detectable signal could have been produced in the inflationary era or by cosmic strings. In this paper, we review the current status of the Parkes Pulsar Timing Array project (the only such project in the Southern hemisphere) and compare the pulsar timing technique with other forms of gravitational-wave detection such as ground- and space-based interferometer systems.