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1.
BMC Public Health ; 24(1): 994, 2024 Apr 09.
Article En | MEDLINE | ID: mdl-38594654

BACKGROUND: The situation of mental health and discipline behaviors of left-behind children's caregivers were not optimistic in rural China. Caregivers' depression might increase the risk of using violent discipline. However, the specific ways in which depressive symptoms impact violent discipline have rarely been explored in rural areas. This study aims to assess the prevalence of violent discipline among left-behind children under 6 years of age in rural China and explore the potential mechanisms of how caregivers' depressive symptoms affect violent discipline. METHODS: We enrolled a total of 396 pairs of left-behind children and their caregivers in our study, which was conducted in 5 counties of Hebei, Henan, Jiangxi, Guizhou, and Sichuan provinces in China. The depressive symptoms of caregivers were measured by using Zung Self-rating Depression Scale (ZSDS) and violent discipline was assessed by the Child Discipline Module of Multiple Indicator Cluster Surveys (MICS). A self-designed questionnaire was utilized to measure caregiver's parenting attitude. Based on the cross-sectional data, controlling for potential confounders, structural equation modeling (SEM) was used to assess the direct and indirect effects of the mediation models by applying the weighted least squares with mean and variance adjusted (WLSMV) estimate. RESULTS: The prevalence of violent discipline, psychological aggression, and physical punishment was 72.7%, 59.3%, and 60.4% respectively of left-behind children under 6 years of age. According to the results of SEM, parenting attitude acted as a suppressor, suppressing the association between caregivers' depressive symptoms and physical punishment/psychological aggression/violent discipline. The caregivers' depressive symptoms positively influenced all the outcome variables by affecting parenting attitudes (p = 0.002, p = 0.013, p = 0.002). CONCLUSIONS: The presence of depressive symptoms in caregivers increases the use of violent discipline through negative parenting attitudes. The mental health status of primary caregivers of left-behind children in rural China needed emphasis and improvement.


Caregivers , Parenting , Child , Humans , Child, Preschool , Cross-Sectional Studies , Caregivers/psychology , Depression/epidemiology , Aggression , China/epidemiology
2.
J Youth Adolesc ; 53(6): 1383-1395, 2024 Jun.
Article En | MEDLINE | ID: mdl-38564098

It is estimated that there are about 23% of all children in China experiencing parental migration and being left behind at hometown. Existing research indicated a significant association between parental migration and children development but overlooked the dynamic changes in family structure caused by parental migration. In this study, data was derived from a nationally representative longitudinal survey-the China Family Panel Studies. The main analyses employed four waves of data (2012, 2014, 2016, and 2018) and included 1401 adolescents aged 10-15 years (Mean:12.35, SD:1.67; 54.2% female). Six typical trajectories of parental migration capturing both migration status at each timepoint and changes in the status across six years were created. Children's depression and internalizing problems and externalizing problems were concerned outcomes. The mediating roles of the caregiver-child interaction and caregiver's depression were examined. Adolescents in the trajectory group described as experiencing transitions between being left behind by both parents and non had a higher risk of depression and internalizing and externalizing problems. Caregivers' depression was a significant mediator between parental migration and adolescent depression.


Depression , Adolescent , Child , Female , Humans , Male , Adolescent Behavior/psychology , Caregivers/psychology , Caregivers/statistics & numerical data , China , Depression/psychology , Depression/epidemiology , East Asian People , Longitudinal Studies , Parent-Child Relations , Parents/psychology , Problem Behavior/psychology , Human Migration
3.
Eur J Med Chem ; 269: 116296, 2024 Apr 05.
Article En | MEDLINE | ID: mdl-38467086

Steroid hybrids have emerged as a type of advantageous compound as they could offer improved pharmacological and pharmaceutical properties. Here, we report a series of novel peptide-dehydroepiandrosterone hybrids, which would effectively induce endoplasmic reticulum stress (ERS) and lead to apoptosis with outstanding in vitro and in vivo anti-melanoma effects. The lead compound IId among various steroids conjugated with peptides and pyridines showed effective in vivo activity in B16 xenograft mice: in medium- and high-dose treatment groups (60 and 80 mg/kg), compound IId would significantly inhibit the growth of tumours by 98%-99% compared to the control group, with the highest survival rate as well. Further mechanism studies showed that compound IId would damage the endoplasmic reticulum and upregulate the ERS markers C/EBP homologous protein (CHOP) and glucose-regulated protein 78 (GRP78), which could further regulate caspase and Bcl-2 family proteins and lead to cell apoptosis. The compound IId was also proven to be effective in inhibiting B16 cell migration and invasion.


Apoptosis , Endoplasmic Reticulum , Humans , Mice , Animals , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum Stress , Peptides/pharmacology , Dehydroepiandrosterone/metabolism , Dehydroepiandrosterone/pharmacology
4.
Sensors (Basel) ; 24(2)2024 Jan 17.
Article En | MEDLINE | ID: mdl-38257683

High-precision positioning systems play a crucial role in various industrial applications. This study focuses on improving the performance of a high-precision multi-degrees-of-freedom (DOF) stage. In terms of the controller design, the following two key challenges must be addressed: the cross-decoupling of different DOFs and the impact of external disturbances. To address these problems, a self-tuning approach is proposed for simultaneous decoupling and disturbance suppression. Initially, the stage undergoes static decoupling using a data-based approach, facilitating feedback control for each DOF through single-input, single-output controllers. Addressing dynamic coupling and external disturbance challenges, we introduced a comprehensive evaluation index and a self-tuning multi-input, multi-output disturbance observer. This approach enabled the evaluation and optimization of the disturbance compensation for all DOFs, ensuring optimal positioning accuracy. Finally, we tested the proposed method using a high-precision multi-DOF stage with a real-time control platform. The results demonstrated a significant reduction in the standard deviations of positioning errors in the rx, ry, and z directions by 46%, 58%, and 6%, respectively. The approach used in this study opens avenues for advancements in the design and control of complex multi-DOF systems.

5.
Child Care Health Dev ; 50(1): e13226, 2024 01.
Article En | MEDLINE | ID: mdl-38265138

BACKGROUND: The early development of left-behind children requires great concern and improvement. Yet, current interventions for left-behind children are mainly focussed on children older than 3. This study aims to assess the effectiveness of a home visiting programme on family responsive care and early development of rural left-behind children and examine whether family responsive care mediates the effects of intervention on child development. METHODS: A quasi-experimental study design was utilized in this study. A stratified clustered sampling was employed to choose villages in programme towns into intervention group. A control village was matched with every intervention village. All of the left-behind children and their caregivers meeting the inclusion criteria in the chosen villages were enrolled in the survey. The outcomes included child development, caregiver's early stimulation, parent-child communication, and learning materials. Baseline assessments were conducted in 2018, and endline assessments were conducted in 2020. RESULTS: In the endline survey, we enrolled 608 children with 258 in the intervention group and 350 in the control group. Left-behind children in the intervention group were less likely to have development delay compared with the control group (odds ratio [OR] = 0.59, 95% confidence interval [CI]: 0.36, 0.96). Migrant parents of children in the intervention group showed higher proportion of expressing emotional support to their children when communicating (OR = 1.69, 95% CI: 1.05, 2.72). Children who received home visits more than once per 2 months had lower level of suspected development delay than children in the control group (OR = 0.34, 95% CI: 0.18, 0.68). Caregiver's early stimulation and migrant parents' emotional support to left-behind children mediated the intervention dose and left-behind children's development. CONCLUSION: Caregiver's early stimulation mediates the intervention and child's development. The findings suggest a promising future for scaling similar early childhood development interventions for left-behind children in rural settings.


House Calls , Research Design , Humans , Child, Preschool , Child Development , China , Communication
6.
Environ Toxicol ; 39(3): 1175-1186, 2024 Mar.
Article En | MEDLINE | ID: mdl-37860912

Magnetite nanoparticles (MNPs) have been extensively detected in the atmospheric environment and implicated as a prominent threat to atherosclerosis, a chronic vascular inflammatory disease. Due to globalization and economic development, the dramatic shift in diet from traditional to high-fat dietary patterns aggravated atherosclerosis progression induced by environmental factors. However, limited knowledge is available regarding vascular risks and underlying mechanisms of airborne MNPs in high-risk populations with high-fat dietary habits. Herein, we demonstrated that MNPs exerted a proatherogenic effect under high-fat dietary patterns, leading to aortic wall thickening, elastic fiber disorganization, macrophage infiltration, and local inflammation. Based on the correlation analysis between MNPs and PM group, we identified that MNPs might be a key PM component in atherogenic toxicity. MNPs exposure disturbed the dynamic process of lipid metabolism, manifested as aortic lipid accumulation, dyslipidemia, and hepatic lipid metabolism disorder, which was modulated by the JAK-STAT pathway. Overall, these findings provide new insight into understanding the cardiovascular risks and mechanisms of MNPs among high-risk populations.


Atherosclerosis , Magnetite Nanoparticles , Humans , Lipid Metabolism , Magnetite Nanoparticles/toxicity , Dietary Patterns , Janus Kinases , Signal Transduction , STAT Transcription Factors
7.
J Affect Disord ; 341: 88-95, 2023 11 15.
Article En | MEDLINE | ID: mdl-37633525

BACKGROUND: Due to multiple factors, left-behind children in rural areas suffer from neurodevelopment delay and their caregivers suffer from depressive symptoms. This study aimed to analyze the effect of caregivers' depressive symptoms on left-behind children's neurodevelopment, with early stimulation and responsive care mediating. METHODS: We conducted a cross-sectional survey in five counties in China. A total of 904 left-behind children aged 0-3 and their primary caregivers were enrolled. The Zung Self-rating Depression Scale (ZSDS) was used to measure caregivers' depressive symptoms. The Ages and Stages questionnaires-third edition (ASQ-3), which contains five domains: communication (CM), gross motor (GM), fine motor (FM), problem-solving (CG), and personal social (PS), was used to screen children for suspected developmental delay (SDD). RESULTS: 31.4 % of left-behind children suffered from SDD, while 39.7 % of left-behind children's caregivers experienced depressive symptoms. Caregivers' ZSDS scores were positively correlated with the SDD on four domains (FM, GM, CG, and PS), while Early stimulation and responsive care was negatively correlated with the SDD on four domains (CM, FM, CG, and PS). LIMITATIONS: The cross-sectional design limited the ability to ascertain causal relations. Besides, the findings may not be generalized to all regions of China due to the heterogeneity of the study population. CONCLUSIONS: Left-behind children under three years old in rural China were at high risk of SDD, while a substantial proportion of their caregivers had depressive symptoms. Caregivers' depressive symptoms may negatively affect the SDD of left-behind children through caregivers providing less early stimulation and responsive care.


Caregivers , Depression , Humans , Child , Child, Preschool , Cross-Sectional Studies , China , Communication
8.
Pest Manag Sci ; 79(8): 2725-2736, 2023 Aug.
Article En | MEDLINE | ID: mdl-36914944

BACKGROUND: Echinochloa glabrescens Munro ex Hook. f. is one of the main Echinochloa spp. seriously invading Chinese rice fields and has evolved resistance to commonly used herbicides. Previously, an E. glabrescens population (LJ-02) with suspected resistance to the acetyl-CoA carboxylase (ACCase)-inhibiting herbicide metamifop was collected. This study aimed to determine its resistance status to metamifop and investigate the internal molecular mechanisms of resistance. RESULTS: Single-dose testing confirmed that the LJ-02 population had evolved resistance to metamifop. Gene sequencing and a relative expression assay of ACCase ruled out target-site based resistance to metamifop in LJ-02. Whole-plant bioassays revealed that, compared with the susceptible population XZ-01, LJ-02 was highly resistant to metamifop and exhibited cross-resistance to fenoxaprop-P-ethyl. Pretreatment with the known glutathione S-transferase (GST) inhibitor, 4-chloro-7-nitrobenzoxadiazole (NBD-Cl), largely reversed the resistance to metamifop by approximately 81%. Liquid chromatography-tandem mass spectrometry analysis indicated that the metabolic rates of one of the major metabolites of metamifop, N-(2-fluorophenyl)-2-hydroxy-N-methylpropionamide (HPFMA), were up to 383-fold faster in LJ-02 plants than in XZ-01 plants. There were higher basal and metamifop-inducible GST activities toward 1-chloro-2,4-dinitrobenzene (CDNB) in LJ-02 than in XZ-01. Six GST genes were metamifop-induced and overexpressed in the resistant LJ-02 population. CONCLUSION: This study reports, for the first time, the occurrence of metabolic metamifop resistance in E. glabrescens worldwide. The high-level metamifop resistance in the LJ-02 population may mainly involve specific isoforms of GSTs that endow high catalytic activity and strong substrate specificity. © 2023 Society of Chemical Industry.


Echinochloa , Herbicides , Echinochloa/genetics , Herbicide Resistance/genetics , Herbicides/pharmacology , Acetyl-CoA Carboxylase/genetics , Acetyl-CoA Carboxylase/metabolism , Glutathione , Transferases
9.
Infant Behav Dev ; 71: 101829, 2023 May.
Article En | MEDLINE | ID: mdl-36842295

BACKGROUND: Home environment provides stimulation and learning opportunities required for children's early development. However, few studies have focused on the effects of home environment on left-behind children's development in rural China. The study aimed to investigate the relationship between home environment and early childhood development of left-behind children under 3 years old in rural China. METHODS: Information about sociodemographic characteristics, caregivers' mental health, home environment and children's development was collected. Infant/Toddler Home Observation for Measurement of the Environment Inventory (IT-HOME) was used to assess home environment. Child's development was evaluated with the Chinese version of the Ages & Stages Questionnaire - third edition. RESULTS: Elevated caregivers' depressive symptoms were associated with a higher risk of total suspected development delay. An increase of one score in the IT-HOME resulted in a 7% decrease in total suspected development delay. Higher scores in the dimensions of involvement and variety were associated with a lower risk of suspected development delay adjusting for covariates. CONCLUSIONS: Our results have implications for home-based intervention aiming at promoting nurturing care as well as caregivers' mental health, which is required for early development of young left-behind children in rural areas of China.


Child Development , Home Environment , Infant , Humans , Child, Preschool , China/epidemiology , Rural Population , Surveys and Questionnaires , Caregivers
10.
Pestic Biochem Physiol ; 186: 105165, 2022 Aug.
Article En | MEDLINE | ID: mdl-35973761

Chinese sprangletop (Leptochloa chinensis (L.) Nees) is a common grass species that severely threatens rice (Oryza sativa L.) cropping systems globally. Cyhalofop-butyl is a highly efficient acetyl-CoA carboxylase (ACCase)-inhibiting herbicide widely used for control of this species in China. However, some L. chinensis populations have gradually evolved resistance to this herbicide in recent years. To better understand the cyhalofop-butyl resistance status of L. chinensis in the major rice planting area of the middle-lower Yangtze River basin, 73 populations collected from the rice fields across Anhui Province were investigated for cyhalofop-butyl susceptibility and potential herbicide resistance-conferring mutations. Single-dose testing indicated that of the 73 populations, 25 had evolved resistance to cyhalofop-butyl and were separately classified as "RRR" and "RR" populations according to their fresh weight reductions, 8 had a high risk of evolving cyhalofop-butyl resistance and were classified as "R?" populations, and 40 were susceptible and classified as "S" populations. Whole-plant dose-response experiments showed that the resistance index (RI) of these R?, RR, and RRR populations to cyhalofop-butyl ranged from 2.47 to 36.94. Target gene sequencing identified seven ACCase resistance mutations (I1781L, W1999C, W2027S, W2027L, W2027C, I2041N, and D2078G), with W1999C and W2027C the two most common detected in about three quarters of all the resistant populations. Seven populations including LASC3, BBHY1, AQQS1, HFFD3, HFFD4, AQWJ1, and HFLJ6 each carrying a specific ACCase mutation were tested for their cross- and multiple-resistance patterns. Compared with a standard susceptible population HFLY1, the seven resistant populations showed distinct cross-resistance. All had low- to high-level cross-resistance to metamifop (RIs ranging from 6.16 to 17.65), fenoxaprop-P-ethyl (RIs ranging from 6.39 to 24.08), and quizalofop-P-ethyl (RIs ranging from 2.20 to 10.25), but responded differently to clodinafop-propargyl and clethodim. Multiple-resistance testing suggested that the seven resistant populations were all susceptible to the 4-hydroxyphenylpyruvate dioxygenase inhibitor tripyrasulfone, the protoporphyrinogen oxidase inhibitor oxyfluorfen, and the auxin mimic herbicide florpyrauxifen. In conclusion, this study has shown that cyhalofop-butyl resistance was prevalent in L. chinensis in Anhui Province, China, and target site mutation was one of the most common resistance mechanisms.


Herbicides , Oryza , Acetyl-CoA Carboxylase/genetics , Butanes , Herbicide Resistance/genetics , Herbicides/pharmacology , Nitriles , Plant Proteins/genetics , Poaceae/genetics
11.
Toxicol Sci ; 189(2): 287-300, 2022 09 24.
Article En | MEDLINE | ID: mdl-35913497

Fine particulate matter (PM) is a leading environmental cause for the increased morbidity and mortality of atherosclerosis (AS) worldwide, but little is known about the toxic component and disturbance of PM exposure on foam cell formation, a crucial pathological process in AS. Airborne magnetite nanoparticles (NPs) have been reported to be detected in human serum, which inevitably encounter with macrophages in atherosclerotic plaques, thus throwing potential disturbance on the formation of macrophage-derived foam cells. Here we comprehensively unveiled that the environmental concentrations of PM exposure triggered and potentiated the formation of macrophage-derived foam cells using both real-ambient PM-exposed mice and AS mice models, including high-fat diet-fed mice and apolipoprotein E-deficient mice. The in vitro model further defined the dose-dependent response of PM treatment on foam cell formation. Interestingly, airborne magnetite NPs rather than nonmagnetic NPs at the same concentration were demonstrated to be the key toxic component of PM in the promoted foam cell formation. Furthermore, magnetite NPs exposure led to abnormal cholesterol accumulation in macrophages, which was attributed to the attenuation of cholesterol efflux and enhancement of lipoprotein uptake, but independent of cholesterol esterification. The in-depth data revealed that magnetite NPs accelerated the protein ubiquitination and subsequent degradation of SR-B1, a crucial transporter of cholesterol efflux. Collectively, these findings for the first time identified magnetite NPs as one key toxic component of PM-promoted foam cell formation, and provided new insight of abnormal cholesterol metabolism into the pathogenesis of PM-induced AS.


Atherosclerosis , Magnetite Nanoparticles , ATP Binding Cassette Transporter 1/metabolism , Animals , Atherosclerosis/chemically induced , Atherosclerosis/metabolism , Cholesterol/metabolism , Ferrosoferric Oxide/metabolism , Foam Cells/pathology , Homeostasis , Humans , Lipoproteins, LDL/metabolism , Magnetite Nanoparticles/toxicity , Mice , Particulate Matter/metabolism , Particulate Matter/toxicity
12.
Environ Sci Technol ; 56(3): 1854-1863, 2022 02 01.
Article En | MEDLINE | ID: mdl-35049283

Virus receptors are highly involved in mediating the entrance of infectious viruses into host cells. Here, we found that typical chemical exposure caused the upregulation of virus receptor mRNA levels. Chemicals with the same structural characteristics can affect the transcription of angiotensin-converting enzyme 2 (ACE2), a dominant receptor of SARS-CoV-2. Some chemicals can also regulate the transcription of ACE2 by similar regulatory mechanisms, such as multilayer biological responses and the crucial role of TATA-box binding protein associated factor 6. The abovementioned finding suggested that chemical mixtures may have a joint effect on the ACE2 mRNA level in the real scenario, where humans are exposed to numerous chemicals simultaneously in daily life. Chemically regulated virus receptor transcription was in a tissue-dependent manner, with the highest sensitivity in pulmonary epithelial cells. Therefore, in addition to genetic factors, exogenous chemical exposure can be an emerging nongenetic factor that stimulates the transcription of virus receptor abundance and may elevate the protein expression. These alterations could ultimately give rise to the susceptibility to virus infection and disease severity. This finding highlights new requirements for sufficient epidemiological data about exposomes on pathogen receptors in the host.


COVID-19 , Receptors, Virus , Angiotensin-Converting Enzyme 2 , Environmental Pollutants , Humans , RNA, Messenger , SARS-CoV-2
13.
Pest Manag Sci ; 78(3): 1176-1186, 2022 Mar.
Article En | MEDLINE | ID: mdl-34822218

BACKGROUND: Chinese sprangletop (Leptochloa chinensis (L.) Nees) is an invasive grass weed severely infesting rice fields across China. In October 2020, a suspected resistant Leptochloa chinensis population HFFD3 that survived the acetyl-CoA carboxylase (ACCase)-inhibiting herbicide cyhalofop-butyl applied at its field-recommended rate was collected from a rice field in Feidong County, Anhui Province, China. This study aimed to determine the resistance profile of HFFD3 to ACCase inhibitors and to investigate its mechanisms of resistance to cyhalofop-butyl. RESULTS: Single-dose testing confirmed that HFFD3 had evolved resistance to cyhalofop-butyl. Two loci encoding plastidic ACCase were each amplified from the susceptible (S) and resistant (R, HFFD3) individual plants. Target gene sequencing and derived cleaved amplified polymorphic sequence assay revealed all the R plants carried a Trp-2027-Leu substitution in their ACCase1,2 copies. Dose-response bioassays revealed that HFFD3 was highly resistant to cyhalofop-butyl and exhibited cross-resistance to metamifop, fenoxaprop-P-ethyl, quizalofop-P-ethyl, and clethodim. Pre-treatment with piperonyl butoxide and 4-chloro-7-nitrobenzoxadiazole considerably reversed the resistance of the R plants to cyhalofop-butyl, by 23% and 43%, respectively. Liquid chromatography-tandem mass spectrometry analysis suggested the metabolic rates of cyhalofop-butyl were significantly faster in the R than in the S plants. CONCLUSION: This study confirmed the first case of an arable weed species featuring cross-resistance to ACCase-inhibiting herbicides due to a novel Trp-2027-Leu mutation of ACCase. Target gene mutation and cytochrome P450s- and glutathione-S-transferases-involved enhanced metabolism may have simultaneously participated in the resistance of HFFD3 population to cyhalofop-butyl.


Acetyl-CoA Carboxylase , Herbicide Resistance , Plant Proteins , Poaceae , Acetyl-CoA Carboxylase/genetics , Butanes , Herbicide Resistance/genetics , Mutation , Nitriles , Plant Proteins/genetics , Plant Weeds/enzymology , Plant Weeds/genetics , Poaceae/embryology , Poaceae/genetics
14.
BMC Public Health ; 21(1): 823, 2021 04 29.
Article En | MEDLINE | ID: mdl-33926397

BACKGROUND: Parent-child separation is a considerable adversity for left-behind children (LBC), but there is little evidence on the association between detailed characteristics of parent-child separation and social-emotional development among LBC. This study examined the characteristics of parent-child separation and its impacts on developmental delay among under-3 LBC in poor rural China. METHODS: We used data from 811 LBC surveyed in five poor counties in rural China in 2018. Detailed characteristics of their parental migration were recalled by their primary caregivers in face-to-face interviews. The children's social-emotional development was measured by using the Ages and Stages Questionnaire: Social-Emotional. Logistic regression was employed to examine the association of detailed characteristics of parent-child separation with early social-emotional problems after adjusting for the children's and primary caregivers' sociodemographic characteristics. RESULTS: 287 (35.4%) children were left behind by fathers and cared for by mothers (FM-MC), while 524 (64.6%) were left behind by both parents and cared for by grandparents (PM-GC). The rate of social-emotional problems among LBC was 36.8% (PM-GC vs FM-MC: 40.6% vs 29.5%; aOR 1.51, 95% CI: 1.06 to 2.16). For paternal migration, the medians of the child's age at the first migration and average duration per migration were 3 months (IQR: 1 to 9 months) and 4.48 months (IQR: 2.38 to 7.54 months), respectively. For maternal migration, the corresponding values were 9 months (IQR: 6 to 13 months) and 4.65 months (IQR: 2.71 to 7.62 months), respectively. On average, LBC had been separated from fathers for 72% of their life due to paternal migration and from mothers for 52% of their life due to maternal migration. No significant association was found between the detailed characteristics of paternal migration and social-emotional development among LBC, while social-emotional problems among LBC were significantly associated with the proportion of cumulative duration of maternal migration in the child's lifetime (aOR 2.83; 95% CI: 1.13 to 7.10). CONCLUSIONS: LBC under 3 years had a high risk of social-emotional problems in poor rural China. Cumulative exposure to maternal migration may be detrimental to LBC's early social-emotional development. Programs are necessary to support these children as well as their families.


Transients and Migrants , Child , China/epidemiology , Cross-Sectional Studies , Divorce , Humans , Parent-Child Relations , Rural Population , Surveys and Questionnaires
15.
Appl Opt ; 60(10): 2861-2869, 2021 Apr 01.
Article En | MEDLINE | ID: mdl-33798165

For passive support of large aperture telescopes, geometric layout optimization of the support structure is one of the most critical tasks because it determines the deformation of the mirror under gravity, which affects the wavefront aberration and image quality of the system. Due to a lack of symmetry, the optimization of an elliptical mirror support can be much more complex compared with circular mirrors. We optimize the geometric layout of axial and lateral support for the tertiary mirror of the Thirty Meter Telescope (TMT). Based on a theoretical analysis of the whiffletree principle, a parametric model of axial support is established based on the multi-point constraint equation. The mirror deformation SlopeRMS of the tertiary mirror under vertical gravity is used as the optimization target of the support points. The axial support point position is optimized by means of a simulated annealing algorithm and a mirror-deformed post-processing script written in Python. The TMT tertiary mirror lateral support also uses the whiffletree structure, and its in-plane layout affects the system's resonant modal frequency and the maximum load at each point. According to the dynamic equation and the static principle, the lateral support optimization model is established. The first-order resonant frequency and maximum load of the support point are the objective function. Through optimization of the axial and lateral support, the overall mirror distortion of the system is improved.

16.
Matern Child Nutr ; 17(1): e13073, 2021 01.
Article En | MEDLINE | ID: mdl-32902154

The period from birth to 2years of age is highly sensitive with respect to the relationship between nutrition and neurodevelopment, but data regarding the association between dietary diversity and early childhood neurodevelopment are limited. We sought to examine the association of two feeding indicators-minimum dietary diversity (MDD) and minimum meal frequency (MMF)-with the neurodevelopment of children aged 6-23 months, using data from a cross-sectional survey conducted in six rural counties in China. Data on 1,534 children were analysed using logistic regression to explore the associations between dietary diversity and early neurodevelopment, with adjustments for the age, sex and prematurity of the child; the age, sex and educational level of the caregiver; and family size, income and simulative care practices and resources. We found that 32.4% of children had suspected developmental delays based on the Chinese version of the Ages and Stages Questionnaires Version 3, whereas 77.0% and 39.2% failed to meet the MDD and MMF, respectively. Meeting the MDD was associated with a 39% lower risk of developmental delays (AOR = 0.61, 95% CI [0.43, 0.86]). There was a significant association between MDD and reduced likelihood of developmental delays in gross motor, fine motor, problem-solving and personal social subscales, whereas MMF was only associated with a lower risk of developmental delays in the gross motor subscale (AOR = 0.63, 95% CI [0.42, 0.94]). We observed an inverse dose-response relationship between the number of food groups consumed and the risk of developmental delays (P < .001).


Diet , Infant Nutritional Physiological Phenomena , Child , Child, Preschool , China/epidemiology , Cross-Sectional Studies , Humans , Infant , Meals
17.
Sci Total Environ ; 762: 143106, 2021 Mar 25.
Article En | MEDLINE | ID: mdl-33143924

The adverse health effects of rare earth elements (REEs) on reproductive health remain a subject of debate, and few clinical observations are available. This study investigated the association between light REEs (LREEs) exposure and the outcome of in vitro fertilization-embryo transfer (IVF-ET). We recruited a total of 305 women undergoing IVF-ET in Beijing City and Shandong Province of northern China. Their demographic information and lifestyle characteristics were collected using questionnaires at enrollment. Fasting blood samples were collected on the day before the IVF-ET treatment cycle began. Serum concentrations of the LREEs of concern were analyzed using inductively coupled plasma-mass spectrometry, and four LREEs were measured with a high detection rate, including lanthanum (La), cerium (Ce), praseodymium (Pr), and neodymium (Nd). We found that a higher serum La concentration was associated with a 30% increased likelihood of clinical pregnancy failure [relative risk (RR) = 1.30, 95% confidence interval (CI): 1.00-1.67] and a 230% increased likelihood of preclinical spontaneous abortion (RR = 3.30, 95% CI: 1.57-6.94). There was a negative correlation between serum La concentration and the number of good-quality oocytes. For the other LREEs, no statistically significant associations were observed. We concluded that a high serum La concentration may have an adverse effect on IVF-ET outcomes.


Metals, Rare Earth , China/epidemiology , Cities , Embryo Transfer , Female , Fertilization in Vitro , Humans , Metals, Rare Earth/analysis , Pregnancy
18.
Opt Express ; 28(26): 40176-40187, 2020 Dec 21.
Article En | MEDLINE | ID: mdl-33379549

Fine alignment of large, segmented telescopes is critical for achieving high angular resolution. Building an instrument with an equally large monolithic aperture is difficult because of the increasing mass and volume. Sparse aperture testing is a lower-cost solution to alignment and metrology, both in the optics shop and at the observatory. We combined sparse aperture testing and curvature sensing to process the highly segmented system's final alignment. First, the stitching error, including tip/tilt/piston and shifting errors, is analyzed theoretically and numerically. These errors are then evaluated by normalized point source sensitivity (PSSn), and the change of PSSn during alignment, which specifies the residual alignment error, is calculated by the defocused donuts. Simulations and experiments demonstrate that the system performance improved by more than 35%. In this paper, we have described the incorporation of sparse aperture testing and curvature sensing algorithms, which can easily cover the tipping and shifting error affecting the traditional methodology.

19.
Int J Public Health ; 65(9): 1807-1809, 2020 Dec.
Article En | MEDLINE | ID: mdl-33184682

The authors would like to correct errors in the publication of the original article. The errors described below and correct details provided.

20.
Int J Public Health ; 65(9): 1711-1721, 2020 Dec.
Article En | MEDLINE | ID: mdl-33057795

OBJECTIVES: This study assessed the early social-emotional development of left-behind children (LBC) in rural China and determined the mediating factors linking parental migration to LBC's developmental outcome. METHODS: We used cross-sectional data of 845 LBC under 3 years old from five counties in rural China in 2018. Social-emotional problems were assessed by the ages and stages questionnaires: social-emotional. Family structure, function, and child nurturing care practices were measured to explore their roles in potential pathways of parental migration affecting early social-emotional development. RESULTS: 36.4% of LBC were identified with social-emotional problems; the rate was higher among LBC with migrant parents than those with migrant fathers (39.9% vs. 30.5%, adjusted OR: 1.40 [95% CI 1.01, 1.93]). Results of structural equation modeling reveal that caregivers' low education and depressive symptoms, poor migrant-caregiver communication, family poverty, and no assistant caregiving weakened home parenting environment, and then contributed to LBC's social-emotional problems. CONCLUSIONS: LBC in early childhood may be at a high risk of social-emotional problems, which are primarily caused by the transition of family structure and function and consequently weakened home environment.


Child Development , Emotions , Parents , Social Behavior , Transients and Migrants/statistics & numerical data , Caregivers/statistics & numerical data , Child Behavior , Child, Preschool , China/epidemiology , Communication , Cross-Sectional Studies , Family Characteristics , Female , Humans , Infant , Latent Class Analysis , Male , Parenting , Rural Population/statistics & numerical data , Socioeconomic Factors
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