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From a conditional adaptation vantage point, early life caregiving adversity likely enhances aspects of cognition needed to manage interpersonal threats. Yet, research examining early life care and offspring cognition predominantly relies upon experiments including affectively neutral stimuli, with findings generally interpreted as “early-life caregiving adversity is, de facto, ‘bad’ for cognitive performance.” Here, in a Southeast Asian sample, we examined observed maternal sensitivity in infancy and cognitive performance 3 years later as preschoolers took part in three tasks, each involving both a socioemotional (SE) and non-socioemotional (NSE) version: relational memory (n = 236), cognitive flexibility (n = 203), and inhibitory control (n = 255). Results indicate the relation between early life caregiving adversity and memory performance significantly differs (Wald test = 7.67, (1), P = 0.006) depending on the SE versus NSE context, with maternal sensitivity in infancy highly predictive of worse memory for SE stimuli, and amongst girls, also predictive of better memory when NSE stimuli are used. Results concerning inhibitory control, as well as cognitive flexibility in girls, also tentatively suggest the importance of considering the SE nature of stimuli when assessing relations between the caregiving environment and cognitive performance. As not all approaches to missing data yielded similar results, implications for statistical approaches are elaborated. We conclude by considering how an adaptation-to-context framework approach may aid in designing pedagogical strategies and well-being interventions that harness pre-existing cognitive strengths.
Data on average iodine requirements for the Chinese population are limited following implementation of long-term universal salt iodisation. We explored the minimum iodine requirements of young adults in China using a balance experiment and the ‘iodine overflow’ hypothesis proposed by our team. Sixty healthy young adults were enrolled to consume a sequential experimental diet containing low, medium and high levels of iodine (about 20, 40 and 60 μg/d, respectively). Each dose was consumed for 4 d, and daily iodine intake, excretion and retention were assessed. All participants were in negative iodine balance throughout the study. Iodine intake, excretion and retention differed among the three iodine levels (P < 0·01 for all groups). The zero-iodine balance derived from a random effect model indicated a mean iodine intake of 102 μg/d, but poor correlation coefficients between observed and predicted iodine excretion (r 0·538 for μg/d data) and retention (r 0·304 for μg/d data). As iodine intake increased from medium to high, all of the increased iodine was excreted (‘overflow’) through urine and faeces by males, and 89·5 % was excreted by females. Although the high iodine level (63·4 μg/d) might be adequate in males, the corresponding level of 61·6 μg/d in females did not meet optimal requirements. Our findings indicate that a daily iodine intake of approximately half the current recommended nutrient intake (120 μg/d) may satisfy the minimum iodine requirements of young male adults in China, while a similar level is insufficient for females based on the ‘iodine overflow’ hypothesis.
Pro-vitamin A carotenoids namely α-, β-carotene and β-cryptoxanthin have potential roles in neurocognitive development, but current literature on these carotenoids mainly focused on preventing cognitive decline in the elderly. This study examined the associations of maternal plasma pro-vitamin A carotenoids concentrations with offspring cognitive development up to 54 months in the GUSTO mother-offspring cohort study.
Materials and Methods
Maternal plasma pro-vitamin A carotenoids concentrations at delivery were determined by ultra-performance liquid chromatography. At age 24 months, the Bayley Scales of Infant and Toddler Development (BSID-III) was used to assess children's development for the following domains: cognitive, receptive and expressive language, and fine and gross motor. At age 54 months, the Kaufman Brief Intelligence Test (KBIT-2) was used to assess children's verbal and non-verbal intelligence. Associations of maternal pro-vitamin A carotenoids with offspring cognitive development at each time point were examined in 419 mother-offspring pairs using linear regressions adjusted for confounders (e.g. maternal demographics, antenatal mental health and breastfeeding duration).
Median (IQR) maternal plasma concentrations (mg/L) were: α-carotene 0.052 (0.032–0.081), β-carotene 0.189 (0.134–0.286), and β-cryptoxanthin 0.199 (0.123–0.304). In 24 months old infants, higher maternal β-cryptoxanthin (per SD increment) were associated with higher scores in most of BSID-III domains: cognitive [β 0.18, (0.08, 0.28) SD], receptive language [β 0.17 (0.07, 0.27) SD], fine motor [β 0.16 (0.06, 0.27) SD], and gross motor [β 0.16 (0.06, 0.27) SD]. Additionally, a 1-SD increment in maternal β-carotene concentrations were associated with 0.16 SD higher scores in BSID-III cognitive domain (95%: 0.04, 0.28), which was attenuated after adjusting for breastfeeding duration. No significant associations were observed between maternal α-carotene concentrations and BSID-III in children at 24 months of age, or between maternal pro-vitamin A carotenoids and KBIT-2 in children at 54 months of age.
Our study provides novel data suggesting a role of maternal pro-vitamin A carotenoids, especially β-cryptoxanthin, in offspring early cognitive development. This adds support to the importance of consuming sufficient amounts of red- and orange-coloured fruit and vegetables (rich sources of β-cryptoxanthin and β-carotene) during pregnancy. Further studies are required in other mother-offspring cohort with larger sample sizes, and intervention trials to confirm an effect of pro-vitamin A carotenoids on neurocognitive development.
Iodine intake and excretion vary widely; however, these variations remain a large source of geometric uncertainty. The present study aims to analyse variations in iodine intake and excretion and provide implications for sampling in studies of individuals or populations. Twenty-four healthy women volunteers were recruited for a 12-d sampling period during the 4-week experiment. The duplicate-portion technique was used to measure iodine intake, while 24-h urine was collected to estimate iodine excretion. The mean intra-individual variations in iodine intake, 24-h UIE (24-h urinary iodine excretion) and 24-h UIC (24-h urinary iodine concentration) were 63, 48 and 55 %, respectively, while the inter-individual variations for these parameters were 14, 24 and 32 %, respectively. For 95 % confidence, approximately 500 diet samples or 24-h urine samples should be taken from an individual to estimate their iodine intake or iodine status at a precision range of ±5%. Obtaining a precision range of ±5% in a population would require twenty-five diet samples or 150 24-h urine samples. The intra-individual variations in iodine intake and excretion were higher than the inter-individual variations, which indicates the need for more samples in a study on individual participants.
Evidence on long-term influences of maternal vitamin B12 deficiency or concentrations on infant cognition is limited. We examined associations between maternal plasma vitamin B12 and cognitive development in 24-month-old infants. Maternal plasma vitamin B12 concentrations were measured at 26–28 weeks’ gestation; infant cognitive development was assessed with the Bayley Scales of Infant and Toddler Development-III at 24 months, for 443 mother–infant pairs from the Growing Up in Singapore Towards Healthy Outcomes cohort. Linear regressions adjusted for key confounders examined associations of maternal vitamin B12 with cognitive, receptive and expressive language, fine and gross motor subscales. Co-occurrence of maternal vitamin B12 with folate or vitamin B6 insufficiencies on child’s cognition was explored. Average maternal plasma vitamin B12 concentrations was 220·5 ± 80·5 pmol/l; 15 % and 41 % of mothers were vitamin B12 deficient (<148 pmol/l) and insufficient (148–220·9 pmol/l), respectively. Infants of mothers with vitamin B12 deficiency had 0·42 (95 % CI −0·70, −0·14) sd lower cognitive scores, compared with infants of mothers with sufficient vitamin B12. Co-occurrence of maternal vitamins B12 and B6 insufficiencies was associated with 0·37 (95 % CI −0·69, −0·06) sd lower cognitive scores in infants compared with infants of mothers sufficient in both vitamins. No significant associations were observed with other subscales. Study findings suggest the possible need to ensure adequate vitamin B12 during pregnancy. The impact of co-occurrence of maternal B-vitamins insufficiencies on early cognitive development warrants further investigation.
Underground Nuclear Astrophysics in China (JUNA) will take the advantage of the ultra-low background in Jinping underground lab. High current accelerator with an ECR source and detectors were commissioned. JUNA plans to study directly a number of nuclear reactions important to hydrostatic stellar evolution at their relevant stellar energies. At the first period, JUNA aims at the direct measurements of 25Mg(p,γ)26 Al, 19F(p,α) 16 O, 13C(α, n) 16O and 12C(α,γ) 16O near the Gamow window. The current progress of JUNA will be given.
Recent research has found that a specific manipulation of body postures can influence psychological states associated with power, including an individual’s feeling of power and risk-taking tendency, but the results vary. The purpose of this study is to replicate previous studies. A pilot experiment examined the validity of 10 postures extracted from multiple former studies. Only 4 postures were consistent with former studies. Experiment 1 replicates the study conducted by Carney, Cuddy, and Yap (2010). The results revealed that posture manipulations did not affect the participants’ risk-taking tendency. Experiment 2 is a preregistered experiment to replicate the study of Carney et al. (2010). Different from Experiment 1, data were analyzed with a Bayesian approach. The results of the former study again failed to be replicated, which indicates that the posture manipulations could not yield any effect on both power feelings and individuals’ risk-taking tendency. Thus, we concluded that (a) holding a specific series of body posture perceived as high or low power does not affect individuals’ feeling of power, and (b) holding a specific series of body posture perceived as high or low power does not affect individuals’ risk-taking tendency.
There is a dearth of data on the iodine balance studies of Chinese population. In the present study, we aimed to explore the appropriate recommended nutrient intake (RNI) of iodine based on healthy Chinese women. A 4-week study was conducted in twenty-five Chinese euthyroid women. Uniform diets with different iodine contents were provided in two different periods, in which non-iodised salt was given in the first 3 weeks, followed by 1 week of iodised salt administration. The total iodine intake from diet, water and air as well as the total iodine excretion through urine, faeces and respiration were monitored and determined. The sweat iodine loss was also considered. Moreover, the regression curve model was established between the 24 h iodine intake and 24 h iodine excretion. The 24 h iodine intake in the two periods was 194·8 (sd 62·9) and 487·1 (sd 177·3) μg/d, respectively. The 24 h iodine excretion was 130·9 (sd 39·5) and 265·4 (sd 71·8) μg/d, respectively. Both 24 h iodine intake and 24 h iodine excretion of the two periods were significantly different (all P<0·05). The iodised salt contributed approximately 62·7 % of the total daily iodine intake. Moreover, 92·3 % (277/300) of samples were in positive balance, while twenty-three cases were in negative balance. Our data show that the estimated average requirement for iodine was 110·5 μg/d. Therefore, the RNI for iodine to non-pregnant, non-lactating Chinese women was 154·7 μg/d.
Zr–Co–Al alloys possess prospects of wide applications in the field of nuclear reactor cladding materials and biomedical materials. (Zr0.5Co0.5)100−xAlx (x = 1, 2, 3 at.%) alloys were prepared by the water-cooling copper mold suction casting technique, and the microstructure and compression mechanical properties of the alloys were investigated. The results showed that the as-cast Zr–Co–Al alloys mainly consisted of the B2 ZrCo phase with columnar or equiaxed grains and a small quantity of intermetallic compounds, i.e., Co2Zr and Zr2Co. The yield strength of Zr–Co–Al alloys increased with increasing Al content, but the plasticity decreased at the same time. The as-cast Zr49.5Co49.5Al1 alloy attained the highest ultimate compression strength up to 2.57 ± 0.02 GPa and the largest compression strain up to ∼54.7%. The B2 to B33 martensitic transformation that occurred during the deformation process was investigated using high resolution transmission electron microscopy. It was concluded that the enhanced plasticity of Zr49.5Co49.5Al1 alloy can be attributed to the transformation induced plasticity associated with the deformation-induced martensitic transformation.
Faster eating rates are associated with increased energy intake, but little is known about the relationship between children’s eating rate, food intake and adiposity. We examined whether children who eat faster consume more energy and whether this is associated with higher weight status and adiposity. We hypothesised that eating rate mediates the relationship between child weight and ad libitum energy intake. Children (n 386) from the Growing Up in Singapore Towards Healthy Outcomes cohort participated in a video-recorded ad libitum lunch at 4·5 years to measure acute energy intake. Videos were coded for three eating-behaviours (bites, chews and swallows) to derive a measure of eating rate (g/min). BMI and anthropometric indices of adiposity were measured. A subset of children underwent MRI scanning (n 153) to measure abdominal subcutaneous and visceral adiposity. Children above/below the median eating rate were categorised as slower and faster eaters, and compared across body composition measures. There was a strong positive relationship between eating rate and energy intake (r 0·61, P<0·001) and a positive linear relationship between eating rate and children’s BMI status. Faster eaters consumed 75 % more energy content than slower eating children (Δ548 kJ (Δ131 kcal); 95 % CI 107·6, 154·4, P<0·001), and had higher whole-body (P<0·05) and subcutaneous abdominal adiposity (Δ118·3 cc; 95 % CI 24·0, 212·7, P=0·014). Mediation analysis showed that eating rate mediates the link between child weight and energy intake during a meal (b 13·59; 95 % CI 7·48, 21·83). Children who ate faster had higher energy intake, and this was associated with increased BMI z-score and adiposity.
By using high purity aluminum powders and multi-walled carbon nanotubes (MWCNTs) as raw materials, MWCNTs/Al composites were fabricated with ball milling, followed by cold pressing, vacuum sintering, and hot extrusion. It was found that when the sintering temperature was 863 K, MWCNTs/Al composite sintered for 4 h showed good comprehensive properties, and its tensile strength and elongation reached to 156 MPa and 21%, respectively. The comprehensive mechanical properties of the composites became better with raising sintering temperature when the sintering time was 4 h. When the sintering temperature raised to 923 K, the tensile strength of the composite reached to 167 MPa which is three times more than that of annealed high purity aluminum, mainly due to the higher density and better interface bonding resulted from higher sintering temperature. CNTs' pulling out were observed obviously in the fractured surfaces, and load transfer may be the main strengthening mechanism.
The ground state properties of Fe3−xCrxO4 (x = 0–3) compounds were studied using first principles calculation. Stress–strain methods were used to evaluate elastic constants of these compounds. These compounds are mechanically stable structures, because they satisfy the mechanical stability criteria. The mechanical moduli were estimated using the Voigt–Reuss–Hill approximation. The calculated bulk moduli of Fe3O4, Fe2CrO4, FeCr2O4, and Cr3O4 are 190.9 GPa, 135.5 GPa, 180.1 GPa, and 235.6 GPa, respectively. Both of anisotropic indexes and 3-D surface contour were used to illustrate the elastic anisotropy. Debye temperature and anisotropy of acoustic velocity of Fe3−xCrxO4 compounds were also investigated. The maximum Debye temperature is attributing to Cr3O4 with 507.6 K among Fe3−xCrxO4 compounds. The minimum thermal conductivity of Fe3−xCrxO4 compounds was estimated by both Clarke's model and Cahill's model. Moreover, 3-D surface contour of the anisotropic thermal conductivity of Fe3−xCrxO4 compounds was obtained based on the Clarke's model and anisotropic Young's modulus.
As electronic devices are indispensable in many aspects of our lives today, their integration with unconventional surfaces is increasingly essential. Electronic devices which maintain their electrical properties upon stretching are desirable for various wearable applications. Stretchable devices demonstrated are conventionally fabricated using semiconductor processing techniques. In this study, we demonstrate stretchable electrodes, which are basic components of electrical circuits, using screen printing, a large area printing method. It provides a low cost and scalable method to fabricate large area stretchable devices. Despite the larger width and thickness of the electrodes which increases the stiffness of the material, stretchability beyond 40% is demonstrated, which is suitable for certain wearable applications. The stretchable electrodes are integrated with light emitting diodes (LEDs) to demonstrate a stretchable LED matrix. The large area LED matrices exhibit variable stretchability, depending on the LED areal coverage. This technique is expected to be applicable in the fabrication of other stretchable, large area, and more complex electronic systems.
Introduction: The mortality of Parkinson’s disease (PD) and its associated risk factors among clinically definite PD patients in China has been rarely investigated. Our study aimed to identify the mortality rates and predictors of death in PD patients in China. Methods: 157 consecutive, clinically definite PD patients from the urban area of Shanghai were recruited from a central hospital based movement disorder clinic in 2006. All patients were regularly followed up at the clinic until December 31, 2011, or death. Mortality and associations with baseline demographics, health and medical factors were then determined within the cohort. Results: After 5 years, 11(7%) patients had died. The standardised mortality ratio was 0.62 (95% CI 0.32 to 1.07, P=0.104). The main causes of death were pneumonia (54.5%, 6/11) and digestive disorders (18.2%, 2/11), respectively. Age at onset, independent living, the mini mental state examination score, the Parkinson’s disease sleep scale score and the Epworth sleepiness scale score at baseline were statistically significantly different between the survival group and the deceased group (P<0.05). Across all participants, risk factors for death included low mini mental state examination score, and high Epworth sleepiness scale score according to a binary variable logistic regression analysis. Conclusions: This study confirms the similar survival of patients with PD to the control population up to a follow-up of 5 years. Interventions tailored to potential risk factors associated with death may offer further benefits.
To explore (i) the prevalence of thyroid dysfunction in populations with adequate and excessive iodine intakes and (ii) the effect of iodine exposure on the prevalence of thyroid dysfunction.
Cross-sectional study was conducted in Hebei in 2010. The population was classified as having adequate or excessive iodine intake according to the iodine concentration in drinking water. Demographic information was collected by questionnaire. Levels of serum thyroid hormones, thyroid autoantibodies and iodine in drinking water and urine were measured.
Villages with adequate or excessive drinking water iodine in Hebei Province, People’s Republic of China.
A total of 854 men and women aged 20–50 years who had lived in the surveyed areas for over 5 years, including 348 from the adequate iodine area (AIA) and 506 from the excessive iodine area (EIA).
Median urinary iodine concentration was 185 μg/l in AIA and 1152 μg/l in EIA. The prevalence of thyroid dysfunction in AIA was 10·3 %, which included 1·1 % with hypothyroidism and 8·1 % with subclinical hypothyroidism; and 20·6 % in EIA, which included 3·6 % with hypothyroidism and 13·6 % with subclinical hypothyroidism. The positive rates of thyroglobulin antibody were 16·1 % in AIA and 11·9 % in EIA; the positive rates of thyroperoxidase antibody were 20·7 % in AIA and 16·4 % in EIA.
Excessive iodine intake may lead to increased prevalence of biochemical thyroid dysfunction, especially biochemical hypothyroidism. This is not related to an increase in prevalence of thyroid antibodies. Women are more susceptible to iodine excess.
Tungsten carbide (WC) particle–reinforced iron matrix surface composites with different content of Cr were fabricated using vacuum evaporative pattern casting technique. It was found that the morphology of carbides changed from continuous net-shape to isolated block-shape patterns. The amount of carbides increase with the increasing Cr content in the matrices. Composites with different Cr content show better abrasive wear resistance than those without Cr. With the increase of Cr content in the matrices, the three-body abrasive wear resistance of the composites increased, while the impact abrasive wear resistance of the composites increased under 1 J impact load, but first increased and then decreased under 3 J impact load. The influences of the addition of Cr in the matrices on the abrasive wear resistance were the synergistic effects of two protecting effects and two supporting effects. The results might provide significant references for the design and practical application of WC particle–reinforced iron matrix surface composites.
The transformation of state-owned enterprises (SOEs) into efficient entities has been an important approach in transition economies. However, the transition literature reveals little about how control structure affects firm performance of transformed SOEs. Drawing on agency theory, we distinguish three modes of control in transformed SOEs: state-controlled, dispersedly controlled, and privately controlled modes and argue that actual control after transformation plays a critical role in determining performance. Examining the impact of different control modes in China, we find that the key is who controls the transformed firm. Non-state-controlled (dispersedly controlled and privately controlled) firms are more likely to have enhanced post-transformation performance and reduced agency costs than state-controlled firms.
Ceria has been aggressively explored for applications as a fuel cell electrolyte or in catalytic converter due to its high oxygen ion conductivity, or as a UV absorption material. It is proven that the properties and applications of ceria nanoparticles are related to their morphologies and sizes. This ability to control the shape and morphology of CeO2 nanoparticles allows the corresponding tuning of their chemical and physical properties. Most of the applications require the use of non-agglomerated nanoparticles, as aggregated nano-particles lead to inhomogeneous mixing, poor sinterability and compromised properties. However, nano-crystals with a primary particle size < 5 nm have a strong tendency to agglomerate. In this work, nano-crystalline particles of CeO2 have been synthesized by a low temperature hydrothermal and solvent thermal synthesis process. Using the precursors of Ce(NO3)3.6H2O:NaOH in different mixing ratio, using polyvinylpyrrolidone (PVP) as the surfactant, the CeO2 particles were synthesized via 24 h hydrothermal and solvent thermal process treatment at reaction temperature of 100 °C and 180 °C using Teflon-lined hydrothermal autoclave. We have optimized the conditions for the two synthesized methods, hydrothermal and solvent thermal, to yield highly crystallized particle with controllable shape, sizes and morphology. X-ray diffraction (XRD) and high-resolution transmission electron microscope (HR-TEM) analysis were used to characterize the crystalline and morphology of the synthesized CeO2 nanoparticles. The optimal reaction condition to prepare the CeO2 of the desired octahedron shaped fluorite structure was established. Based on the results, the hydrothermal synthesis method yields nanocrystalline CeO2 sizes of ∼6 nm, while the solvent synthesis method yields nanocrystalline CeO2 sizes of 2-3 nm at the optimal conditions. The hydrothermal synthesis method produced better particles in terms of crystallinity and morphology under HR-TEM. Temperature also plays a part in crystallinity and sizes of the CeO2 nanoparticles. The crystallinity and size of the CeO2 nanoparticles increases when using higher treatment temperature for both hydrothermal and solvent thermal methods. The growth mechanism of the shape and morphology of the CeO2 will also be discussed.
Recent studies indicate that bipolar disorder is associated with mitochondrial dysfunction and oxidative stress. Previous studies in our laboratory have shown that the mood stabilizer lithium inhibits oxidative stress. The α,β-unsaturated aldehyde 4-hydroxy-2-nonenal (4-HNE), a major product of lipid peroxidation, is able to exert cytotoxicity and disturb cellular function by forming protein adducts. The purpose of this study is to determine whether chronic lithium treatment prevents 4-HNE-protein adduction in an amphetamine-induced hyperactive mania-like model. We found that repeated amphetamine stimulation significantly induced hyperactive behaviour, decreased activities of mitochondrial complexes I and III, and increased 4-HNE-protein adducts in rat frontal cortex, and that chronic lithium treatment inhibited both amphetamine-induced hyperactivity and 4-HNE-protein adduction. Monoamine neurotransmitters are involved in the aetiology and pathology of bipolar disorder and other psychiatric diseases, and also contribute significantly to amphetamine-induced behavioural effects. Vesicular monoamine transporter 2 (VMAT2) is critical in packaging monoamine neurotransmitters. We found that 4-HNE can form protein adducts with VMAT2. Repeated amphetamine stimulation significantly increased 4-HNE-VMAT2 adducts, while chronic lithium treatment reduced amphetamine-increased 4-HNE-VMAT2 adducts in rat frontal cortex. Our findings suggest that chronic lithium treatment may inhibit amphetamine-induced hyperactive mania-like behaviour by preventing 4-HNE-VMAT2 adduction. This finding also indicates that prevention of 4-HNE-VMAT2 adduction may contribute in part to the pharmacological action of lithium for the treatment of bipolar disorder.