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Although alienation toward parents is important for children (for current mental health status or later interpersonal relationships in adulthood), it is undervalued and even lacks a standardized tool of assessment. Moreover, the large number of left-behind children in China is a cause of public concern. However, their experienced alienation toward their parents remains unclear, which may be important for early detection or intervention for behavioral problems in this population. Hence, the current study aimed to develop an alienation inventory for children and then use it to investigate the experienced alienation toward parents in Chinese left-behind children.
Two studies were carried out. Study 1 was designed to develop a standard inventory of alienation toward parents (IAP). In study 2, 8361 children and adolescents (6704 of them were left-behind status) of the Chongqing area, aged between 8 and 19 years old, were recruited for investigation. All participants were surveyed with a standard sociodemographic questionnaire, children's cognitive style questionnaire, children's depression inventory, adolescent self-rating life events checklist, and newly built IAP in study 1.
In study 1, we developed a two-component (communication and emotional distance) and 18-item (9 items for maternal or paternal form, respectively) IAP questionnaire. In study 2, exploratory factor analysis indicated an expected two-factor structure of IAP, which was confirmed by confirmatory factor analysis. The Cronbach's alpha coefficients showed a good reliability (0.887 and 0.821 for maternal and paternal form, respectively). Children with absent mother experienced the highest alienation toward parents. Boys as well as children aged 8–10 years old experienced higher alienation toward parents. Poor communication with parents (sparse or no connection), level of left-behind condition (parents divorced, been far away from parents), and psychosocial vulnerability (stressful life events, negative cognitive style) were risk factors of alienation toward parents.
The current study develops a two-factor (communication and emotional distance) IAP, which offers a reliable tool to assess experienced alienation of affection toward parents in children aged between 8 and 19 years old. Our result is the first investigation of experienced alienation and potential influential factors in Chinese left-behind children. The findings that children with absent mother experience higher alienation toward parents, as well as three recognized risk factors for alienation of affection toward parents (poor communication with absent parents, worse left-behind condition, and psychosocial vulnerability), give valuable guidance for parents who intend to leave or who are already leaving as well as for government policymaking.
Losing one's only child is a major traumatic life event that may lead to post-traumatic stress disorder (PTSD); however, the underlying mechanisms of its psychological consequences remain poorly understood. Here, we investigated subregional hippocampal functional connectivity (FC) networks based on resting-state functional magnetic resonance imaging and the deoxyribonucleic acid methylation of the human glucocorticoid receptor gene (NR3C1) in adults who had lost their only child.
A total of 144 Han Chinese adults who had lost their only child (51 adults with PTSD and 93 non-PTSD adults [trauma-exposed controls]) and 50 controls without trauma exposure were included in this fMRI study (age: 40–67 years). FCs between hippocampal subdivisions (four regions in each hemisphere: cornu ammonis1 [CA1], CA2, CA3, and dentate gyrus [DG]) and methylation levels of the NR3C1 gene were compared among the three groups.
Trauma-exposed adults, regardless of PTSD diagnosis, had weaker positive FC between the left hippocampal CA1, left DG, and the posterior cingulate cortex, and weaker negative FC between the right CA1, right DG, and several frontal gyri, relative to healthy controls. Compared to non-PTSD adults, PTSD adults showed decreased negative FC between the right CA1 region and the right middle/inferior frontal gyri (MFG/IFG), and decreased negative FC between the right DG and the right superior frontal gyrus and left MFG. Both trauma-exposed groups showed lower methylation levels of the NR3C1 gene.
Adults who had lost their only child may experience disrupted hippocampal network connectivity and NR3C1 methylation status, regardless of whether they have developed PTSD.
Pilophyllia Ge and Yu, 1974 represents a major group of distinctive amplexoid corals in the Silurian, whose taxonomic relationships, species composition, and evolutionary trends remain contentious. A critical revision of type material and new specimens of several species (and subspecies) assigned to Pilophyllia, including the type species P. involuta Ge and Yu, 1974, provides solutions to some of these problems. Pilophyllia is revised to include only those forms characterized by a distinct peripheral stereozone and amplexoid major septa with club-shaped rhabdacanths set in thick lamellar stereomes. Other species, previously referred to Pilophyllia but having generally short septa with wedge-shaped rhabdacanths, are transferred herein to the new genus Neopilophyllia Wang. Both genera, together with other Silurian amplexoid rugosan genera such as Amplexoides, are referred to the new family Amplexoididae Wang, which is thought to be evolutionarily unrelated to the much younger (Devonian to early Carboniferous) amplexoid rugosan family Amplexidae Chapman, 1893. The first appearance of Neopilophyllia n. gen. in the middle Telychian, much later than that of Pilophyllia in the late Rhuddanian, probably marks a significant stage during the evolution of Silurian amplexoid corals.
In the present study, direct numerical simulation (DNS) is carried out in a minimal channel at
to sustain healthy turbulence below
. Turbulence intensities are compared with those of the motions at the same scales as the minimal channel in the full-sized channel at
(Hoyas & Jiménez, Phys. Fluids, vol. 20 (10), 2008, article 101511). They show good agreement in
. The universal signals for the three velocity components similar to that in the predictive model of Marusic et al. (Science, vol. 329 (5988), 2010, pp. 193–196) are extracted from the DNS data of the full-sized channel. They correspond well to the near-wall velocity fluctuations in the minimal flow unit (MFU). The predictive models for the three components of near-wall velocity fluctuations are proposed based on the MFU data. The predicted turbulence intensities as well as the joint probability density functions of velocity fluctuations agree well with the DNS results of the full-sized channel turbulence.
The pathophysiology of cognitive impairment in patients with the major depressive disorder (MDD) may involve neuroinflammation mediated by cytokines.
The aim of this study was to examine the serum interleukin-6 (IL-6) levels, sustained attention, and their association in patients with MDD.
Thirty patients with MDD and 30 healthy controls were enrolled in this case-control study. Sustained attention was measured using the Rapid Visual Information Processing (RVP) task in the Cambridge Neuropsychological Tests Automated Battery. The serum IL-6 levels of all subjects were assessed by sandwich enzyme-linked immunosorbent assays.
There were significant differences in the log10RVP total hits, log10RVP total misses, and log10RVP mean latency between patients with MDD and healthy controls (F = 6.04, p = 0.017; F = 19.77, p < 0.0001; F = 14.42, p < 0.0001, respectively). The serum levels of Log10IL-6 were significantly higher in patients with MDD than in healthy controls (F = 192.27, p < 0.0001). The log10IL-6 levels were also positively correlated with the log10RVP mean latency in patients with MDD (r = 0.45, p = 0.013). A further stepwise multivariate regression analysis indicated that the log10IL-6 levels were significantly associated with the log10RVP mean latency in patients with MDD (β = 0.31, t = 2.41, p = 0.025).
Our data suggested that increased IL-6 levels were associated with the psychopathology of MDD, and that abnormal IL-6 levels were implicated in the impairment of sustained attention in patients with MDD.
In this paper, we review the status of the multifunctional experimental platform at the National Laboratory of High Power Laser and Physics (NLHPLP). The platform, including the SG-II laser facility, SG-II 9th beam, SG-II upgrade (SG-II UP) facility, and SG-II 5 PW facility, is operational and available for interested scientists studying inertial confinement fusion (ICF) and a broad range of high-energy-density physics. These facilities can provide important experimental capabilities by combining different pulse widths of nanosecond, picosecond, and femtosecond scales. In addition, the SG-II UP facility, consisting of a single petawatt system and an eight-beam nanosecond system, is introduced including several laser technologies that have been developed to ensure the performance of the facility. Recent developments of the SG-II 5 PW facility are also presented.
We examined the in vitro developmental competence of parthenogenetic activation (PA) oocytes activated by an electric pulse (EP) and treated with various concentrations of AZD5438 for 4 h. Treatment with 10 µM AZD5438 for 4 h significantly improved the blastocyst formation rate of PA oocytes in comparison with 0, 20, or 50 µM AZD5438 treatment (46.4% vs. 34.5%, 32.3%, and 24.0%, respectively; P < 0.05). The blastocyst formation rate was higher in the group treated with AZD5438 for 4 h than in the groups treated with AZD5438 for 2 or 6 h (42.8% vs. 38.6% and 37.2%, respectively; P > 0.05). Furthermore, 66.67% of blastocysts derived from these AZD5438-treated PA oocytes had a diploid karyotype. The blastocyst formation rate of PA and somatic cell nuclear transfer (SCNT) embryos was similar between oocytes activated by an EP and treated with 2 mM 6-dimethylaminopurine for 4 h and those activated by an EP and treated with 10 µM AZD5438 for 4 h (11.11% vs. 13.40%, P > 0.05). In addition, the level of maturation-promoting factor (MPF) was significantly decreased in oocytes activated by an EP and treated with 10 µM AZD5438 for 4 h. Finally, the mRNA expression levels of apoptosis-related genes (Bax and Bcl-2) and pluripotency-related genes (Oct4, Nanog, and Sox2) were checked by RT-PCR; however, there were no differences between the AZD5438-treated and non-treated control groups. Our results demonstrate that porcine oocyte activation via an EP in combination with AZD5438 treatment can lead to a high blastocyst formation rate in PA and SCNT experiments.
The female and nymph of Ixodes (Pholeoixodes) kangdingensis n. sp. are described based on both morphology and analysis of 16S rRNA gene sequences. Specimens of this new tick species were collected from a Siberian weasel (Mustela sibirica) in Kangding County, Sichuan Province, China. The morphological features of the female and nymph are unique to distinguish I. kangdingensis n. sp. from other members of the subgenus Pholeoixodes, including the presence of distinctly shaped cornua, anterior and posterior processes on palpal article I and a large angular projection on each side of the hypostome. Partial sequence of 16S rRNA gene grouped this species with Ixodes arboricola and Ixodes lividus with sequence divergence of new species from I. arboricola 4·16% and from I. lividus 8·49%. Data on the phylogenetic position, hosts, geographic distribution and key to females of closely related species are also provided.
Watermelon [Citrullus lanatus (Thunb.) Matsum. & Nakai var. lanatus] is an economically important vegetable belonging to the Cucurbitaceae family. Genotypes that exhibit agronomically important traits are selected for the development of elite cultivars. Understanding the genetic diversity and the genotype population structure based on molecular markers at the genome level can speed up the utilization of diverse genetic resources for varietal improvement. In the present study, we carried out an analysis of genetic diversity based on 3882 SNP markers across 37 core watermelon genotypes, including the most widely used watermelon varieties and wild watermelon. Based on the SNP genotyping data of the 37 watermelon genotypes screened, gene diversity and polymorphism information content values across chromosomes varied between 0.03–0.5 and 0.02–0.38, with averages of 0.14 and 0.13, respectively. The two wild watermelon genotypes were distinct from cultivated varieties and the remaining 35 cultivated genotypes were differentiated into three major clusters: 20 genotypes were grouped in cluster I; 11 genotypes were grouped in cluster II; three advanced breeding lines of yellow fruit flesh and genotype SW043 were grouped in cluster III. The results from neighbour-joining dendrogram, principal coordinate analysis and STRUCTURE analysis approaches were consistent, and the grouping of genotypes was generally in agreement with their origins. Here we reveal the genetic relationships among the core watermelon genotypes maintained at the Jiangsu Academy of Agricultural Sciences, China. The molecular and phenotypic characterization of the existing core watermelon genotypes, together with specific agronomic characteristics, can be utilized by researchers and breeders for future watermelon improvement.
Monotonic and cyclic tension–tension tests with an upper stress in the GPa regime have been performed on Cu–Si nanowires. The results show that the exceptional high strength of these nanomaterials is maintained or even improved upon cyclic loading. Post-mortem transmission electron microscopy gives insight in the microstructural evolution. Fatigue-induced grain growth correlates with an observed increase in compliance, the formation of dislocation networks, and an increase in tensile strength.
The recent development of in-situ liquid stages for (scanning) transmission electron microscopes now makes it possible for us to study the details of electrochemical processes under operando conditions. As electrochemical processes are complex, care must be taken to calibrate the system before any in-situ/operando observations. In addition, as the electron beam can cause effects that look similar to electrochemical processes at the electrolyte/electrode interface, an understanding of the role of the electron beam in modifying the operando observations must also be understood. In this paper we describe the design, assembly, and operation of an in-situ electrochemical cell, paying particular attention to the method for controlling and quantifying the experimental parameters. The use of this system is then demonstrated for the lithiation/delithiation of silicon nanowires.
In this study, we present a new numerical model for crystal growth in a vertical solidification system. This model takes into account the buoyancy induced convective flow and its effect on the crystal growth process. The evolution of the crystal growth interface is simulated using the phase-field method. A semi-implicit lattice kinetics solver based on the Boltzmann equation is employed to model the unsteady incompressible flow. This model is used to investigate the effect of furnace operational conditions on crystal growth interface profiles and growth velocities. For a simple case of macroscopic radial growth, the phase-field model is validated against an analytical solution. The numerical simulations reveal that for a certain set of temperature boundary conditions, the heat transport in the melt near the phase interface is diffusion dominant and advection is suppressed.
The organic light-emitting (OLE) materials have attracted great interest due to their potential applications in sensors, biodetectors and OLE devices. However, highly efficient emission from organic solids is still a great challenge because of the aggregation-caused quenching effect. In this article, a three-dimensional (3D) organic-inorganic hybrid nanoparticle, based on polyhedral oligomeric silsesquioxane (POSS), was precisely fabricated via click chemistry with high yield, and its structure was characterized by Fourier transform infrared spectroscopy, 1H, and 29Si nuclear magnetic resonance spectroscopies, and Matrix-Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry, respectively. The resultant 3D organic-inorganic nanohybrid showed significantly enhanced emission in solid film (Φfilm 80%) with a slight red-shift as compared with its organic counterpart, (Φfilm 14%), which exhibits a large red-shift in solid film, due to the deaggregation effect of POSS. Simultaneously, the resultant nanohybrid also exhibited good film formability, excellent spectrum and thermal stability (>250 °C) due to the introduction of POSS.
It has been systematically investigated about the magnetic properties of the composite and single-phase SrFe12O19 prepared with the precursor of different Fe3+/Sr2+ molar ratios of 12:1, 11:1 and 10:1, respectively. With increasing the calcinations temperature, the coercivity of all samples decreases which can be determined by the stress model. The δm(H) results indicate that the intergrain exchangecoupling interaction exists both in composite and in single-phase SrFe12O19, resulting in the remanence magnetization enhancement, and the magnetostatic interaction become dominant in the samples with higher calcinations temperatures. The irreversible susceptibilities χirr(H) curves show that there may exhibit the exchange-spring behavior in the composite SrFe12O19 with more soft magnetic γ-Fe2O3, and the irreversible switching field may be qualitatively used to determine the coercivity magnitude.
To replace ternary polymer with binary polymer, a novel bifunctional comonomer β-methylhydrogen itaconate (MHI) was synthesized to prepare poly(acrylonitrile-co-β-methylhydrogen itaconate) [P(AN-co-MHI)] copolymer used for carbon fiber precursor. The structural evolution and stabilization mechanism of P(AN-co-MHI) and polyacrylonitrile (PAN) during stabilization were studied by Fourier transform infrared spectroscopy, x-ray diffraction, differential scanning calorimetry, thermogravimetry, and kinetic investigation. The activation energy (Ea) of the stabilization reactions were calculated by Kissinger method and Ozawa method. The results show that the P(AN-co-MHI) exhibits a lower stabilization temperature than terpolymers containing similar chemistry component and a significantly improved stabilization performance compared with PAN homopolymer, such as lower cyclization temperature, lower Ea (85.36 kJ/mol), and larger extent of stabilization under the same condition, which is mainly attributed to the initiation of MHI comonomer through an ionic cyclization mechanism. The dehydrogenation of P(AN-co-MHI) is also promoted by the incorporation of comonomer MHI into PAN chains. Simultaneously, the rheological analysis shows that P(AN-co-MHI) possesses better spinnability than PAN, which is beneficial for preparation of high performance carbon fiber.