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To analyse the association between sleep duration and quality with food intake, chrononutrition patterns, and weight gain during pregnancy. A prospective cohort study was conducted with 100 pregnant women. Data collection occurred once during each gestational trimester. The assessment of sleep quality and duration was performed using the Pittsburgh Sleep Quality Index. Food intake was assessed using three 24-h recalls in each trimester. Body weight was measured during the three trimesters, and height was measured only once to calculate the BMI. Linear regression analyses were performed to associate sleep duration and quality with food consumption and weight gain variables. Longer sleep duration was associated with a later dinner in the first trimester (β = 0·228, P = 0·025) and earlier in the third trimester (β = –0·223, P = 0·026), in addition to a later morning snack in the second trimester (β = 0·315, P = 0·026). Worse sleep quality was associated with higher total energy intake (β = 0·243, P = 0·044), total fat (β = 0·291, P = 0·015) and the chrononutrition variables such as a higher number of meals (β = 0·252, P = 0·037), higher energetic midpoint (β = 0·243, P = 0·044) and shorter fasting time (β = –0·255, P = 0·034) in the third trimester. Sleep quality was also associated with a higher BMI in the first trimester of pregnancy (β = 0·420, P = < 0·001). Most of the associations found in the present study show that poor sleep is associated with higher energy and fat intake and higher BMI. Longer sleep duration was associated with a later dinner in early pregnancy and an earlier dinner in late pregnancy, as well as with a later morning snack in the second trimester of pregnancy.
We study the capillary rise of viscous liquids into sharp corners formed by two surfaces whose geometry is described by power laws $h_i(x) = c_i x^n$, $i = 1,2$, where $c_2 > c_1$ for $n \geq 1$. Prior investigations of capillary rise in sharp corners have shown that the meniscus altitude increases with time as $t^{1/3}$, a result that is universal, i.e. applies to all corner geometries. The universality of the phenomenon of capillary rise in sharp corners is revisited in this work through the analysis of a partial differential equation for the evolution of a liquid column rising into power-law-shaped corners, which is derived using lubrication theory. Despite the lack of geometric similarity of the liquid column cross-section for $n>1$, there exist a scaling and a similarity transformation that are independent of $c_i$ and $n$, which gives rise to the universal $t^{1/3}$ power law for capillary rise. However, the prefactor, which corresponds to the tip altitude of the self-similar solution, is a function of $n$, and it is shown to be bounded and monotonically decreasing as $n\to \infty$. Accordingly, the profile of the interface radius as a function of altitude is also independent of $c_i$ and exhibits slight variations with $n$. Theoretical results are compared against experimental measurements of the time evolution of the tip altitude and of profiles of the interface radius as a function of altitude.
This study examined the relationship between childhood diet quality and arterial stiffness and thickness during adolescence/early adulthood. Participants were from the Avon Longitudinal Study of Parents and Children (ALSPAC) with dietary data at ages 7, 10 and 13 years and pulse wave velocity (PWV) and carotid intima-media thickness (cIMT) at ages 17 and/or 24 years. Diet quality (DQ) was assessed using five scores: a children’s Mediterranean-style diet (C-rMED) Z-score, a children’s Dietary Inflammatory Z-score (C-DIS), a DASH diet Z-score, a children’s Eatwell Guide (C-EWG) Z-score reflecting UK dietary guidelines and a data-driven obesogenic Z-score. Adjusted regression models examined the associations between DQ scores at 7–13 years and PWV and cIMT at 17 and 24 years. In adjusted models, a high v. low Obesogenic Z-score at 7 and 10 years was associated with higher PWV at 17: β 0.07 (95 % CI 0.01, 0.13) and β 0.10 (95 % CI 0.04, 0.16), respectively. A high v. low C-rMED Z-score at 7 years was associated with lower PWV at 17 (β −0.07; 95 % CI −0.14, −0.01). A high (more anti-inflammatory) vs low C-DIS Z-score at 10 years was associated with a lower PWV at 17 years: β −0.06 (95 % CI −0.12, −0.01). No other associations were observed. In conclusion, an Obesogenic dietary pattern in childhood (7–10 years) was related to increased arterial stiffness, while Mediterranean-style and anti-inflammatory diets were related to decreased arterial stiffness in adolescence. This highlights the importance of establishing healthy dietary habits early in life to protect against vascular damage.
Optic nerve hypoplasia (ONH) and septo-optic-pituitary dysplasia (SOD) are neurodevelopmental disorders associated with congenital visual impairment. Our aim was to investigate associations between several ophthalmic and neuroimaging features in patients with ONH/SOD.
Methods:
A retrospective chart and neuroimaging review was performed in patients with ONH/SOD. Ophthalmic signs (e.g., monocular best-corrected visual acuity [BCVA], nystagmus, and strabismus) and neuroimaging data were extracted and their associations were investigated.
Results:
There were 128 patients (70 males) with ONH/SOD who had neuroimaging. Their mean age at the end of the study was 13.2 (SD: 7.5) years. Ophthalmic data were available on 102 patients (58 males). BCVA varied from normal to no light perception. There were statistically significant associations between: (A) Reduced optic nerve or chiasm size on neuroimaging and more severely impaired BCVA and (B) laterality of the reduced optic nerve or chiasm size on neuroimaging and laterality of: (1) The eye with reduced BCVA, (2) small optic disc size, and (3) RAPD, if present (p ≤ 0.0002 each). The presence of symmetrically small optic nerves on MRI was significantly more common in patients with nystagmus than when nystagmus was absent (N = 96, 75% vs. 38.6%, p < 0.0001). The presence of neuronal migration disorders, their type and laterality were not associated with BCVA and laterality of the reduced BCVA.
Conclusion:
The functional and structural associations in ONH are consistent with the impaired visual function that results from the hypoplastic anterior visual pathways. However, these associations were not perfectly concordant making prediction of adult BCVA challenging in these patients.
Aphis spiraecola Patch is one of the most economically important tree fruit pests worldwide. The pyrethroid insecticide lambda-cyhalothrin is commonly used to control A. spiraecola. In this 2-year study, we quantified the resistance level of A. spiraecola to lambda-cyhalothrin in different regions of the Shaanxi province, China. The results showed that A. spiraecola had reached extremely high resistance levels with a 174-fold resistance ratio (RR) found in the Xunyi region. In addition, we compared the enzymatic activity and expression level of P450 genes among eight A. spiraecola populations. The P450 activity of A. spiraecola was significantly increased in five regions (Xunyi, Liquan, Fengxiang, Luochuan, and Xinping) compared to susceptible strain (SS). The expression levels of CYP6CY7, CYP6CY14, CYP6CY22, P4504C1-like, P4506a13, CYP4CZ1, CYP380C47, and CYP4CJ2 genes were significantly increased under lambda-cyhalothrin treatment and in the resistant field populations. A L1014F mutation in the sodium channel gene was found and the mutation rate was positively correlated with the LC50 of lambda-cyhalothrin. In conclusion, the levels of lambda-cyhalothrin resistance of A. spiraecola field populations were associated with P450s and L1014F mutations. Our combined findings provide evidence on the resistance mechanism of A. spiraecola to lambda-cyhalothrin and give a theoretical basis for rational and effective control of this pest species.
The goal of this paper is to go further in the analysis of the behavior of the number of descents in a random permutation. Via two different approaches relying on a suitable martingale decomposition or on the Irwin–Hall distribution, we prove that the number of descents satisfies a sharp large-deviation principle. A very precise concentration inequality involving the rate function in the large-deviation principle is also provided.
These volumes conclude a series initiated in 1974, marking almost fifty years of effort by a huge cohort of scholars. This review is thus a valedictory for the whole series as well as an account of what we have learned from the most recent volumes about Darwin's final years (1879–82). The project was begun by Frederick Burckhardt, who shared the editorial role for the early volumes with Sydney Smith and a rolling sequence of assistant editors and advisers who eventually comprised a significant fraction of the leading members of what used to be called the ‘Darwin industry’. Smith passed away in 1988 (volume 7 notes his legacy). Burkardt too left this world in 2007 – volume 16, part 1 includes an obituary, but his name has been retained and Cambridge University Press still ask that the series be cited as ‘Burkhardt et al.’ Duncan Porter took over for volumes 8–15, again with a sequence of fellow editors and assistants, after which James Secord became head of the project through its final years. The dedications of successive volumes record the efforts of individual scholars who have aided the teams and the involvement of the many institutions and foundations that have leant moral and material support over the years. For those of us with Cambridge connections, the University Library will not seem the same without the presence of the team it supported.
Childhood maltreatment is an established risk factor for psychopathology. However, it remains unclear how childhood traumatic events relate to mental health problems and how the brain is involved. This study examined the serial mediation effect of brain morphological alterations and emotion-/reward-related functions on linking the relationship from maltreatment to depression. We recruited 156 healthy adolescents and young adults and an additional sample of 31 adolescents with major depressive disorder for assessment of childhood maltreatment, depressive symptoms, cognitive reappraisal and anticipatory/consummatory pleasure. Structural MRI data were acquired to identify maltreatment-related cortical and subcortical morphological differences. The mediation models suggested that emotional maltreatment of abuse and neglect, was respectively associated with increased gray matter volume in the ventral striatum and greater thickness in the middle cingulate cortex. These structural alterations were further related to reduced anticipatory pleasure and disrupted cognitive reappraisal, which contributed to more severe depressive symptoms among healthy individuals. The above mediating effects were not replicated in our clinical group partly due to the small sample size. Preventative interventions can target emotional and reward systems to foster resilience and reduce the likelihood of future psychiatric disorders among individuals with a history of maltreatment.
In this article, we establish the Grothendieck–Serre conjecture over valuation rings: for a reductive group scheme $G$ over a valuation ring $V$ with fraction field $K$, a $G$-torsor over $V$ is trivial if it is trivial over $K$. This result is predicted by the original Grothendieck–Serre conjecture and the resolution of singularities. The novelty of our proof lies in overcoming subtleties brought by general nondiscrete valuation rings. By using flasque resolutions and inducting with local cohomology, we prove a non-Noetherian counterpart of Colliot-Thélène–Sansuc's case of tori. Then, taking advantage of techniques in algebraization, we obtain the passage to the Henselian rank-one case. Finally, we induct on Levi subgroups and use the integrality of rational points of anisotropic groups to reduce to the semisimple anisotropic case, in which we appeal to properties of parahoric subgroups in Bruhat–Tits theory to conclude. In the last section, by using extension properties of reflexive sheaves on formal power series over valuation rings and patching of torsors, we prove a variant of Nisnevich's purity conjecture.
This paper introduces a viscous vortex model for predicting the optimal drag reduction of riblet surfaces, eliminating the need for expensive direct numerical simulations (DNSs) or experiments. The footprint of a typical quasi-streamwise vortex, in terms of the spanwise and wall-normal velocities, is extracted from smooth-wall DNS flow fields in close proximity to the surface. The extracted velocities are then averaged and used as boundary conditions in a Stokes-flow problem, wherein riblets with various cross-sectional shapes are embedded. Here, the same smooth-wall-based boundary conditions can be used for riblets, as we observe from the DNSs that the quasi-streamwise vortices remain unmodified apart from an offset. In particular, the position of these vortices remain unpinned above small riblets. The present approach is compared with the protrusion-height model of Luchini et al. (J. Fluid Mech., vol. 228, 1991, pp. 87–109), which is also based on a Stokes calculation, but represents the vortex with only a uniform spanwise velocity boundary condition. The key novelty of the present model is the introduction of a wall-normal velocity component into the boundary condition, thus inducing transpiration at the riblet crests, which becomes relevant as the riblet size increases. Consequently, the present model allows for the drag-reduction prediction of riblets up to the optimal size. The present approach does not rely on the scale separation formally required by homogenisation techniques, which are only applicable for vanishingly small riblets.
We present necessary and sufficient conditions for an operator of the type sum of squares to be globally hypoelliptic on $T \times G$, where T is a compact Riemannian manifold and G is a compact Lie group. These conditions involve the global hypoellipticity of a system of vector fields on G and are weaker than Hörmander’s condition, while generalizing the well known Diophantine conditions on the torus. Examples of operators satisfying these conditions in the general setting are provided.
This study compared the concentrations, types and distributions of sialic acid (SA) in human milk at different stages of the postnatal period with those in a range of infant formulas. Breast milk from mothers of healthy, full-term and exclusively breastfed infants was collected on the 2nd (n 246), 7th (n 135), 30th (n 85) and 90th (n 48) day after birth. The SA profiles of human milk, including their distribution, were analysed and compared with twenty-four different infant formulas. Outcome of this observational study was the result of natural exposure. Only SA of type Neu5Ac was detected in human milk. Total SA concentrations were highest in colostrum and reduced significantly over the next 3 months. Approximately 68·7–76·1 % of all SA in human milk were bound to oligosaccharides. Two types of SA, Neu5Ac and Neu5Gc, have been detected in infant formulas. Most SA was present in infant formulas combined with protein. Breastfed infants could receive more SA than formula-fed infants with the same energy intake. Overall, human milk is a preferable source of SA than infant formulas in terms of total SA content, dynamics, distribution and type. These SA profiles in the natural state are worth to be considered by the production of formulas because they may have a great effect on infant nutrition and development.
Ageing-in-place has become an internationally favoured policy and practice response to population ageing. However, limited literature has sought to understand this concept from Chinese older adults' perspectives, especially in rural China. The purpose of this study is to explore how older adults in rural China conceptualise ageing-in-place. This study took a qualitative approach by carrying out in-depth interviews with snowball-sampled older adults from a rural village in Shandong Province, China (N = 30). Participants conceptualised their ageing-in-place as consisting of two phases: first, when they felt self-reliant, these older adults preferred to live independently in the village; and second, when their capability declined, they would expect care-giving from their children. Autonomy was essential to participants' decision to age in place. The village offered both a physical and social environment in which participants could sustain their self-identity. This decision to age in place independently also related to participants' proactive adaptation to their children's evolving practices of filial piety. Still, had their capabilities declined, they reported they would expect their children's care-giving and move in with their children. Our findings suggest that older adults in rural China conceptualise ageing-in-place as a dynamic process that evolves as they age and experience changes in their needs and capabilities. This perception expands critical notions of ageing-in-place by highlighting rural older adults' flexible conceptualisation of the ‘place’ in which they plan to age. This study sheds light on socioculturally nuanced understandings of ageing-in-place while providing evidence to inform tailored policy and practice development in rural China.
We present a systematic study to investigate the fluid–structure interaction (FSI) of subaqueous spherical pendulums with several solid-to-fluid mass ratios $m^*\in [1.14, 14.95]$ and corresponding Reynolds numbers of up to $\textit {Re}\sim 10^4$. A digital object tracking (DOT) method was employed to track the oscillating pendulum spheres whereas the time-resolved 3-D particle tracking velocimetry (tr-3D-PTV) was used to measure the flow field around the spheres. The data obtained from the coupling of the two measuring techniques provide novel insights into the dynamics of pendulum sphere oscillations, instantaneous pressure fluctuations related to vortex shedding around the spheres and the way they are influenced by the vortex and wake interactions. Namely, we show that during the downward motion of the pendulum spheres, vortex rings are shed off the spheres which, in turn, induce short-lived propulsion and, subsequently, distinct deceleration. Further, we used the measured data to improve an existing basic model of pendulum motion, which has significant discrepancies for the period and peak amplitude predictions. We did this by incorporating a vortex-induced drag term and a wake interaction term into the equation. Finally, the improved equations are shown to be capable of predicting the subaqueous pendulum dynamics with high accuracy, for the investigated range of $m^*$. The study thus extends the current understanding of basic fluid dynamic mechanisms such as added mass, nonlinear drag, vortex and pressure dynamics.