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We study the convective and absolute forms of azimuthal magnetorotational instability (AMRI) in a cylindrical Taylor–Couette (TC) flow with an imposed azimuthal magnetic field. We show that the domain of the convective AMRI is wider than that of the absolute AMRI. Actually, it is the absolute instability which is the most relevant and important for magnetic TC flow experiments. The absolute AMRI, unlike the convective one, stays in the device, displaying a sustained growth that can be experimentally detected. We also study the global AMRI in a TC flow of finite height using direct numerical simulation and find that its emerging butterfly-type structure – a spatio-temporal variation in the form of axially upward and downward travelling waves – is in a very good agreement with the linear analysis, which indicates the presence of two dominant absolute AMRI modes in the flow giving rise to this global butterfly pattern.
Current evidence indicates that maternal diets before and during pregnancy could influence rates of preterm birth, low birth weight (LBW) and small for gestational age (SGA) births. However, findings have been inconsistent. This review summarised evidence concerning the effects of maternal diets before and during pregnancy on preterm birth, LBW and SGA. Systematic electronic database searches were carried out using PubMed, Embase, Scopus and Cochrane library using the preferred reporting items for systematic reviews and meta-analyses guidelines. The review included forty eligible articles, comprising mostly of prospective cohort studies, with five randomised controlled trials. The dietary patterns during pregnancy associated with a lower risk of preterm birth were commonly characterised by high consumption of vegetables, fruits, whole grains, fish and dairy products. Those associated with a lower risk of SGA also had similar characteristics, including high consumption of vegetables, fruits, legumes, seafood/fish and milk products. Results from a limited number of studies suggested there was a beneficial effect on the risk of preterm birth of pre-pregnancy diet quality characterised by a high intake of fruits and proteins and less intake of added sugars, saturated fats and fast foods. The evidence was mixed for the relationship between maternal dietary patterns during pregnancy and LBW. These findings indicate that better maternal diet quality during pregnancy, characterised by a high intake of vegetables, fruits, whole grains, dairy products and protein diets, may have a synergistic effect on reducing the risk of preterm birth and SGA.
While birthweight of offspring is associated with pre-pregnancy body mass index (BMI) and later risk of obesity, its mediating effect between the association of maternal pre-pregnancy BMI and offspring’s childhood anthropometrics has rarely been investigated. This study aimed to examine whether offspring birthweight is a mediator in the association between pre-pregnancy BMI and offspring’s childhood anthropometrics. The study included 1,618 mother–child pairs from the Australian Longitudinal Study on Women’s Health and Mothers and their Children’s Health Study. Children’s anthropometrics [mean age 8.6 (s.d. =3.0) years] were calculated from the mothers’ self-reported child weight and height measures. G-computation was used to estimate the natural direct and indirect (via birthweight) effects of pre-pregnancy BMI. In the fully adjusted model for maternal sociodemographic and lifestyle factors, the natural direct effects of pre-pregnancy obesity on child BMI-for-age, height-for-age, weight-for-age and weight-for-height outcomes were, β (95% confidence interval, CI), 0.75 (0.55, 0.95), 0.13 (−0.07, 0.32), 0.62 (0.44, 0.80) and 0.57 (0.24, 0.90), respectively. The corresponding natural indirect effects were 0.04 (−0.04, 0.12), −0.01 (−0.09, 0.07), −0.01 (−0.08, 0.07) and 0.09 (−0.05, 0.23). Similar results were observed for pre-pregnancy overweight and pre-pregnancy BMI as a continuous scale. Most of the effect of pre-pregnancy obesity on childhood weight-related anthropometric outcomes appears to be via a direct effect, not mediated through offspring’s birthweight.
Perimenopausal disorders (PDs) are prevalent and importantly affect quality of life among middle-aged women. Yet, very little is known about the developmental origins of these disorders. The objective of this study was to investigate the associations of birth characteristics with PDs. This cohort study is based on archived birth records for birth weight and gestational age, and followed prospectively in Swedish inpatient and outpatient registers for 8 years (n=3212). The main outcomes were menopausal and climacteric states (e.g. flushing, sleeplessness), perimenopausal bleeding and other PDs (e.g. atrophic vaginitis). Cox proportional hazards regression models were used to estimate the hazard ratios (HRs) for three subtypes of PDs separately. During the follow-up, 218 women had PDs, among whom 125 had menopausal and climacteric states, 61 had perimenopausal bleeding and 58 had other PDs as first recorded disorder. Birth weight was linearly associated with incidence rate of menopausal and climacteric states [HR=1.66 per 1 kg increase, 95% confidence interval (95% CI)=1.14–2.41]. Gestational age (rather than birth weight) was associated with incidence rate of other PDs (HR=0.87 per 1 week increase, 95% CI=0.79–0.95). Neither birth weight nor gestational age was associated with perimenopausal bleeding. Similar results were found after adjustment for other early-life and adult socio-demographic characteristics. This observational study provides, for the first time, evidence regarding the developmental origins of PDs. Future research is required to investigate the underlying causal mechanisms, which may shed further light on the etiology of this class of disorders.
There is limited evidence on the association between maternal preconception body mass index (BMI) trajectories and pregnancy complications and child development. This study examined the relationships of maternal BMI trajectories, diabetes and hypertensive disorders during pregnancy and offspring’s childhood physical and cognitive development. Data were from the Australian Longitudinal Study on Women’s Health and the Mothers and their Children’s Health study (n=771). Women’s preconception BMI trajectories were identified using group-based trajectory modelling. Children’s physical and cognitive development (up to the average age of 5 years) were obtained from the Ages and Stages Questionnaire (suspected gross motor delay) and the Australian Early Development Census (AEDC). Generalized estimating equation models, adjusted for maternal sociodemographic and lifestyle factors, were used for analyses. Three distinct BMI trajectories were identified (normative, chronically overweight and chronically obese). Children born to chronically obese women were more likely to be classified as developmentally vulnerable/at-risk on AEDC domains; gross and fine motor skills [risk ratio (RR)=1.64, 95% confidence interval (CI): 1.04, 2.61] and communication skills and general knowledge (RR=1.71, 95% CI: 1.09, 2.68). They also had an elevated risk of suspected gross motor delay (RR=2.62, 95% CI: 1.26, 5.44) compared with children born to women with a normative BMI trajectory. Maternal diabetes or hypertensive disorders during pregnancy were not associated with child outcomes. Maternal preconception BMI trajectories were associated with poorer childhood development. This study finding underscores the importance of excessive weight gain prevention throughout the reproductive stage of life.
A recent study on ladybird, Menochilus sexmaculatus (Fabricius) demonstrates that males perform post-copulatory mate guarding in the form of prolonged mating durations. We investigated whether food resource fluctuation affects pre- and post-copulatory behaviour of M. sexmaculatus. It has not been studied before in ladybirds. For this, adults were subjected to prey resource fluctuations sequentially at three levels: post-emergence (Poe; 10 days), pre-mating (Prm; 24 h) and post-mating (Pom; 5 days; only female). The food resource conditions at each level could be any one of scarce, optimal or abundant. Pre-copulatory and post-copulatory behaviour, and reproductive output were assessed. Post-emergence and pre-mating nutrient conditions significantly influenced the pre-copulatory behaviour. Males reared on scarce post-emergence conditions were found to require significantly higher number of mating attempts to establish mating unlike males in the other two food conditions. Under scarce post-emergence and pre-mating conditions, time to commencement of mating and latent period were high but opposite result was obtained for mate-guarding duration. Fecundity and per cent egg viability were more influenced by post-mating conditions, with scarce conditions stopping oviposition regardless of pre-mating and post-emergence conditions. Present results indicate that pre- and post-copulatory behaviour of ladybird is plastic in nature in response to food resource fluctuations.
Background: Traditional neurosurgical techniques and/or stereotactic radiotherapy, although effective for solid tumors, can be associated with high morbidity and be relatively ineffective for long-term control of cystic sellar/parasellar tumors. The rationale of our study was to examine the efficacy and safety of stereotactic intracavitary instillation of 90yttrium colloid for the primary treatment of cystic tumors. Methods: As part of a Health Canada approved clinical trial, we have enrolled nine patients (6 females, 3 males; mean age 64, range 43 to 83 years) for treatment of symptomatic and/or enlarging cysts. Ten cystic sellar/parasellar lesions underwent right frontal stereotactic insertion of 90yttrium colloid to deliver a radiation dose of 200 Gy to the cyst wall. Results: Compared with pre-treatment cyst volumes (mean 4.6 cc; range 0.8-16.1 cc), the cysts decreased in size at 3 months (2.6 cc; 0.2-10 cc) with further shrinkage (n=5) at 9 months (1 cc; 0.1-2.7 cc). Of 9 patients with pre-operation visual field defects, 6 showed improvement. The single complication was a delayed (1 month) incomplete CNIII palsy. Conclusions: Our early experience indicates that 90yttrium colloid delivered to a cystic craniopharyngioma provides an efficacious alternative to open surgery for primary treatment of these cystic lesions.
We propose here a class of numerical schemes for the approximation of weak solutions to nonlinear hyperbolic systems in nonconservative form—the notion of solution being understood in the sense of Dal Maso, LeFloch, and Murat (DLM). The proposed numerical method falls within LeFloch-Mishra's framework of schemes with well-controlled dissipation (WCD), recently introduced for dealing with small-scale dependent shocks. We design WCD schemes which are consistent with a given nonconservative system at arbitrarily high-order and then analyze their linear stability. We then investigate several nonconservative hyperbolic models arising in complex fluid dynamics, and we numerically demonstrate the convergence of our schemes toward physically meaningful weak solutions.
There is limited longitudinal research that has looked at the longer term incidence of depressive symptoms, comparing women with a hysterectomy to women without a hysterectomy. We aimed to investigate the association between hysterectomy status and the 12-year incidence of depressive symptoms in a mid-aged cohort of Australian women, and whether these relationships were modified by use of exogenous hormones.
We used generalised estimating equation models for binary outcome data to assess the associations of the incidence of depressive symptoms (measured by the 10-item Centre for Epidemiologic Studies Depression Scale) across five surveys over a 12-year period, in women with a hysterectomy with ovarian conservation, or a hysterectomy with bilateral oophorectomy compared with women without a hysterectomy. We further stratified women with hysterectomy by their current use of menopausal hormone therapy (MHT). Women who reported prior treatment for depression were excluded from the analysis.
Compared with women without a hysterectomy (n = 4002), both women with a hysterectomy with ovarian conservation (n = 884) and women with a hysterectomy and bilateral oophorectomy (n = 450) had a higher risk of depressive symptoms (relative risk (RR) 1.20; 95% confidence interval (CI) 1.06–1.36 and RR 1.44; 95% CI 1.22–1.68, respectively). There were differences in the strength of the risk for women with a hysterectomy with ovarian conservation, compared with those without, when we stratified by current MHT use. Compared with women without a hysterectomy who did not use MHT, women with a hysterectomy with ovarian conservation who were also MHT users had a higher risk of depressive symptoms (RR 1.57; 95% CI 1.31–1.88) than women with a hysterectomy with ovarian conservation but did not use MHT (RR 1.17; 95% CI 1.02–1.35). For women with a hysterectomy and bilateral oophorectomy, MHT use did not attenuate the risk. We could not rule out, however, that the higher risk seen among MHT users may be due to confounding by indication, i.e. MHT was prescribed to treat depressive symptoms, but their depressive symptoms persisted.
Women with a hysterectomy (with and without bilateral oophorectomy) have a higher risk of new incidence of depressive symptoms in the longer term that was not explained by lifestyle or socio-economic factors.
Developmental rates are highly variable, both within and between genotypes and populations. But the rationale for two differential (slow and fast) developmental rates within same cohort under varying prey supply has yet not been explored. For this purpose, we investigated the effect of scarce and abundant prey supply on slow and fast development at 27°C in two aphidophagous ladybirds, Menochilus sexmaculatus (Fabricius) and Propylea dissecta (Mulsant) and its effect on their body mass and reproductive attributes. The ladybirds were provided with scarce and abundant supply of Aphis craccivora Koch under standardized abiotic conditions in the laboratory. A clear bimodal (two peaks, where the first peak represented the fast developing individuals and the second peak slow developing individuals) pattern of distribution for both prey supplies was obtained, which got skewed with change in prey supply. On abundant prey supply, more fast developing individuals (139 M. sexmaculatus and 123 P. dissecta) were found and less (46 M. sexmaculatus and 36 P. dissecta) on scarce prey supply. Slow developing individuals had female biased sex ratio, higher longevity and lower body mass. Fast developing females laid higher number of eggs with higher egg viability. Results of the study are indicative of occurrence and constancy of the slow and fast developing individuals in the egg batch.
A review is presented of Synchrotron X-ray Topography and KOH etching studies carried out on n type 4H-SiC offcut substrates before and after homo-epitaxial growth to study defect replication and strain relaxation processes and identify the nucleation sources of both interfacial dislocations (IDs) and half-loop arrays (HLAs) which are known to have a deleterious effect on device performance. We show that these types of defects can nucleate during epilayer growth from: (1) short segments of edge oriented basal plane dislocations (BPDs) in the substrate which are drawn by glide into the epilayer; and (2) segments of half loops of BPD that are attached to the substrate surface prior to growth which also glide into the epilayer. It is shown that the initial motion of the short edge oriented BPD segments that are drawn from the substrate into the epilayer is caused by thermal stress resulting from radial temperature gradients experienced by the wafer whilst in the epi-chamber. This same stress also causes the initial glide of the surface half-loop into the epilayer and through the advancing epilayer surface. These mobile BPD segments provide screw oriented segments that pierce the advancing epilayer surface that initially replicate as the crystal grows. Once critical thickness is reached, according to the Mathews-Blakeslee model , these screw segments glide sideways under the action of the mismatch stress leaving IDs and HLAs in their wake. The origin of the mismatch stress is shown to be associated with lattice parameter differences at the growth temperature, arising from the differences in doping concentration between substrate and epilayer.
In the present study, resource partitioning by natural conspecific size variants (small and large) of ladybird, Menochilus sexmaculatus (Fabricius) females, in response to varying prey densities was assessed using functional and numerical responses as measures of prey density. The prey provided was small (second) and large (fourth) instars of Aphis craccivora Koch. Results revealed that under choice condition, small and large females of M. sexmaculatus consumed higher number of small and large instars, respectively. Small females exhibited a modified Type II functional response on small aphid instars and a Type II functional response on fourth aphid instars. Large females exhibited a Type II functional response when provided either second or fourth aphid instars. Numerical response in terms of numbers of eggs laid by both the females increased with increase in the density of either of the aphid instars. However, in small females, oviposition had a positive correlation with the numbers of small and large aphid instars consumed; being strong for the small aphid instars. While in large females, oviposition was positively correlated with the numbers of large aphid instars consumed and not small aphid instars. It therefore seems that intraspecific resource partitioning in M. sexmaculatus occurs prominently in large females than the small females.
In the present study predation parameters, i.e. consumption rate, conversion efficiency and growth rate, and total developmental duration of immature stages of two congeneric ladybirds, Coccinella septempunctata (L.) and Coccinella transversalis F., have been evaluated in presence of conspecific and heterospecific fourth instar larval and adult female tracks. We hypothesized that the semiochemicals within larval/adult female tracks might act as foraging/feeding deterrent pheromones (FDPs) and would reduce the predation parameters; and would prolong total developmental duration of ladybird predators. Results of the study positively affirmed our hypothesis. The deterrence in prey consumption and reduction in conversion efficiency and growth rate was density dependent with species-specific variations. Consumption rate, conversion efficiency, and growth rate of larval instars decreased and the total developmental duration of immature stages increased when exposed to an increasing density of zero, two, three, and four conspecific/heterospecific larval/adult female tracks. Between ladybird species, C. septempunctata had higher consumption rate, growth rate, and total developmental durations, whereas conversion efficiency was higher in C. transversalis. Despite the presence of semiochemical tracks as foraging barriers, early instars showed higher conversion efficiencies and growth rates, whereas fourth instars had highest consumption rate in all experimental treatments. The present study, therefore, suggests that semiochemical tracks significantly reduce the predation potential and prolong developmental duration of conspecifics and heterospecifics. They, thus behave as FDP.
We provide a ‘user guide’ to the literature of the past twenty years concerning the modelling and approximation of discontinuous solutions to nonlinear hyperbolic systems that admit small-scale dependent shock waves. We cover several classes of problems and solutions: nonclassical undercompressive shocks, hyperbolic systems in nonconservative form, and boundary layer problems. We review the relevant models arising in continuum physics and describe the numerical methods that have been proposed to capture small-scale dependent solutions. In agreement with general well-posedness theory, small-scale dependent solutions are characterized by a kinetic relation, a family of paths, or an admissible boundary set. We provide a review of numerical methods (front-tracking schemes, finite difference schemes, finite volume schemes), which, at the discrete level, reproduce the effect of the physically meaningful dissipation mechanisms of interest in the applications. An essential role is played by the equivalent equation associated with discrete schemes, which is found to be relevant even for solutions containing shock waves.
Maternal filarial infection influences the risk of acquiring infection and development of immunity in children. Here we have analysed the blood samples of 60 mothers (24 infected and 36 uninfected) and their corresponding cord bloods to assess the impact of maternal infection on the anti-sheath antibodies and cytokine production in neonates born from them. About 69·4% of non-infected mothers and their cord bloods showed the presence of anti-sheath antibodies, while only 16·6% of the cord bloods from infected mothers were positive for it. The IL-10 level was significantly high in cord bloods of infected mothers compared with non-infected mothers. At the same time the IL-10 level was also observed to be remarkably high in cord bloods of both infected and non-infected mothers negative for anti-sheath antibody. In contrast, IFN-γ levels were significantly high in cord bloods of non-infected mothers compared with infected mothers and the increment was prominent in cord bloods of both infected and non-infected mothers positive for anti-sheath antibody. The study reveals that the presence or absence of anti-sheath antibodies in association with cytokines skews the filarial specific immunity to either Th1 or Th2 responses in neonates. This may affect the natural history of filarial infection in early childhood.
Long-term tillage and fertilizer experiments were conducted in rice in kharif followed by lentil in dry subhumid Inceptisols at Varanasi and Faizabad; horse gram at Phulbani and linseed at Ranchi in moist subhumid Alfisols in rabi during 2001 to 2010. The study was conducted to assess the effect of conventional tillage (CT), low tillage + interculture (LT1) and low tillage + herbicide (LT2) together with 100% N (organic) (F1), 50% N (organic) + 50% N (inorganic) (F2) and 100% N (inorganic) (F3) on productivity, profitability, rainwater and energy use efficiencies. The results at Varanasi revealed that CT was superior with mean yield of 2389 kg ha−1, while F1 was superior with 2378 kg ha−1 in rice. At Faizabad, CT was superior with mean rice yield of 1851 kg ha−1 and lentil yield of 977 kg ha−1, while F1 was superior with 1704 and 993 kg ha−1 of rice and lentil, respectively. At Phulbani, F2 was superior with rice yield of 1170 kg ha−1. At Ranchi, F2 with rice yield of 986 kg ha−1 and F3 with linseed yield of 224 kg ha−1 were superior. The regression model of crop seasonal rainfall and yield deviations indicated an increasing trend in rice yield over mean (positive deviation) with increase in rainfall at all locations; while a decreasing trend (negative deviation) was found for lentil at Faizabad, horse gram at Phulbani and linseed at Ranchi. Based on economic analysis, CTF1 at Varanasi and Faizabad, CTF2 at Phulbani and LT2F2 at Ranchi were superior.