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Although aberrant brain regional responses are reported in social anxiety disorder (SAD), little is known about resting-state functional connectivity at the macroscale network level. This study aims to identify functional network abnormalities using a multivariate data-driven method in a relatively large and homogenous sample of SAD patients, and assess their potential diagnostic value.
Forty-six SAD patients and 52 demographically-matched healthy controls (HC) were recruited to undergo clinical evaluation and resting-state functional MRI scanning. We used group independent component analysis to characterize the functional architecture of brain resting-state networks (RSNs) and investigate between-group differences in intra-/inter-network functional network connectivity (FNC). Furtherly, we explored the associations of FNC abnormalities with clinical characteristics, and assessed their ability to discriminate SAD from HC using support vector machine analyses.
SAD patients showed widespread intra-network FNC abnormalities in the default mode network, the subcortical network and the perceptual system (i.e. sensorimotor, auditory and visual networks), and large-scale inter-network FNC abnormalities among those high-order and primary RSNs. Some aberrant FNC signatures were correlated to disease severity and duration, suggesting pathophysiological relevance. Furthermore, intrinsic FNC anomalies allowed individual classification of SAD v. HC with significant accuracy, indicating potential diagnostic efficacy.
SAD patients show distinct patterns of functional synchronization abnormalities both within and across large-scale RSNs, reflecting or causing a network imbalance of bottom-up response and top-down regulation in cognitive, emotional and sensory domains. Therefore, this could offer insights into the neurofunctional substrates of SAD.
This research communication investigated the role and the underlying mechanism of sn-1-acylglycerol-3-phosphate O-acyltransferase 6 (AGPAT6) in acetate-induced mTORC1 signaling activation and milk fat synthesis in dairy cow mammary epithelial cells. The data showed AGPAT6 knockdown significantly decreased acetate-induced phosphorylation of mTORC1 signaling molecules and intracellular triacylglycerol (TAG) content, whereas this inhibition effect was reversed after the addition of 16:0,18:1 phosphatidic acid (PA), suggesting that AGPAT6 could generate PA in response to acetate simulation, that in turn activates mTORC1 signaling. PPARγ is the upstream regulator of AGPAT6 upon acetate stimulation. Luciferase assay with clones containing various deletions and mutation in AGPAT6 promoter showed that there is a RXRα binding sequence located at −96 bp of AGPAT6 promoter. Acetate stimulation significantly increased the interaction between PPARγ and AGPAT6 via this RXRα binding site. Taken together, our data indicated that AGPAT6 could activate mTORC1 signaling by producing PA during acetate-induced milk fat synthesis, and PPARγ acts as a transcription factor to mediate the effect of acetate on AGPAT6 via RXRα.
Parenting practices and relationships with peers are crucial aspects of youth socialization. Although theoretically expected reciprocal associations between changes in maladaptive parenting and adolescent peer victimization exist, there is a lack of studies that examine this link and address the mediating mechanisms at the within-person level. This longitudinal study examined reciprocal relations between peer victimization and two types of maladaptive parenting including harsh punishment and psychological control, and the potential mediating roles of internalizing and externalizing problems within these relations, by disentangling between- and within-person effects. A total of 4,731 Chinese early adolescents (44.9% girls; Mage = 10.91 years, SD = 0.72) participated in a four-wave longitudinal study with 6-month intervals. The results of random intercept cross-lagged panel modeling showed: (a) harsh punishment did not directly predict peer victimization, and vice versa; (b) psychological control directly predicted peer victimization, and vice versa; (c) psychological control indirectly predicted peer victimization via internalizing problems, and peer victimization also indirectly predicted psychological control via internalizing problems. These findings provide evidence of a bidirectional spillover effect between psychological control and peer victimization at the within-person level, suggesting Chinese early adolescents may become caught in a vicious cycle directly or indirectly via their internalizing problems.
The role of dietary factors in osteoporotic fractures (OFs) in women is not fully elucidated. We investigated the associations between incidence of OF and dietary calcium, magnesium and soy isoflavone intake in a longitudinal study of 48 584 postmenopausal women. Multivariable Cox regression was applied to derive hazard ratios (HRs) and 95 % confidence intervals (CIs) to evaluate associations between dietary intake, based on the averages of two assessments that took place with a median interval of 2⋅4 years, and fracture risk. The average age of study participants is 61⋅4 years (range 43⋅3–76⋅7 years) at study entry. During a median follow-up of 10⋅1 years, 4⋅3 % participants experienced OF. Compared with daily calcium intake ≤400 mg/d, higher calcium intake (>400 mg/d) was significantly associated with about a 40–50 % reduction of OF risk among women with a calcium/magnesium (Ca/Mg) intake ratio ≥1⋅7. Among women with prior fracture history, high soy isoflavone intake was associated with reduced OF risk; the HR was 0⋅72 (95 % CI 0⋅55, 0⋅93) for the highest (>42⋅0 mg/d) v. lowest (<18⋅7 mg/d) quartile intake. This inverse association was more evident among recently menopausal women (<10 years). No significant association between magnesium intake and OF risk was observed. Our findings provide novel information suggesting that the association of OF risk with dietary calcium intake was modified by Ca/Mg ratio, and soy isoflavone intake was modified by history of fractures and time since menopause. Our findings, if confirmed, can help to guide further dietary intervention strategies for OF prevention.
Recognition of obstacle type based on visual sensors is important for navigation by unmanned surface vehicles (USV), including path planning, obstacle avoidance, and reactive control. Conventional detection techniques may fail to distinguish obstacles that are similar in visual appearance in a cluttered environment. This work proposes a novel obstacle type recognition approach that combines a dilated operator with the deep-level features map of ResNet50 for autonomous navigation. First, visual images are collected and annotated from various different scenarios for USV test navigation. Second, the deep learning model, based on a dilated convolutional neural network, is set and trained. Dilated convolution allows the whole network to learn deep features with increased receptive field and further improves the performance of obstacle type recognition. Third, a series of evaluation parameters are utilised to evaluate the obtained model, such as the mean average precision (mAP), missing rate and detection speed. Finally, some experiments are designed to verify the accuracy of the proposed approach using visual images in a cluttered environment. Experimental results demonstrate that the dilated convolutional neural network obtains better recognition performance than the other methods, with an mAP of 88%.
Though schizophrenia (SZ) and obsessive-compulsive disorder (OCD) are conceptualized as distinct clinical entities, they do have notable symptom overlap and a tight association. Graph-theoretical analysis of the brain connectome provides more indicators to describe the functional organization of the brain, which may help us understand the shared and disorder-specific neural basis of the two disorders.
To explore the static and dynamic topological organization of OCD and SZ as well as the relationship between topological metrics and clinical variables.
Resting state functional magnetic resonance imaging data of 31 OCD patients, 49 SZ patients, and 45 healthy controls (HC) were involved in this study (Table 1). Using independent component analysis to obtain independent components (ICs) (Figure 1), which were defined as nodes for static and dynamic topological analysis.
Static analysis showed the global efficiency of SZ was higher than HC. For nodal degree centrality, OCD exhibited decreased degree centrality in IC59 (located in visiual network) (P = 0.03) and increased degree centrality in IC38 (located in salience network) (P = 0.002) compared with HC. Dynamic analysis showed OCD exhibited decreased dynamics of degree centrality in IC38 (P = 0.003) compared with HC, which showed a negative correlation with clinical scores in OCD. While SZ showed decreased dynamics of degree centrality in IC76 (located in sensory motor network) compared with OCD (P=0.009), which showed a positive correlation with clinical scores in SZ (Figure 2).
These changes are suggestive of disorder-specific alternation of static and dynamic brain topological organization in OCD and SZ.
Obsessive-compulsive disorder (OCD) and schizophrenia (SZ) are both severe psychiatric disorders. Though these two disorders have distinct typical symptoms, there are partial polygenic overlap and comorbidity between the two disorders. However, few studies have explored the shared and disorder-specific brain function underlying the neural pathophysiology of the two disorders, especially in the aspect of dynamics.
To explore the abnormal characteristics of the dynamic functional connectivity (dFC) in OCD and SZ as well as the association between dFC metrics and symptom severity.
The resting state functional magnetic resonance imaging data of 31 patients with OCD, 49 patients with SZ, and 45 healthy controls were analyzed using independent component analysis to obtain independent components (ICs) and assigned them into eight brain networks (Figure 1), then used the sliding-window approach to generate dFC matrices. Using k-means clustering, we obtained three reoccurring dFC states (Figure 2), and state transition metrics were obtained
In a sparsely connected state (state 1), SZ showed both increased fractional time and mean dwell time than controls (P=0.047 and P=0.033) and OCD (P=0.001 and P=0.003). In a state characterized by negative FC between networks (state 2), OCD showed both increased fractional time and mean dwell time than controls (P=0.032 and P=0.013) and SZ (P=0.005 and P=0.003). Moreover, the fractional time of state 2 was positively correlated with anxiety scores in OCD (r=0.535, P=0.021, FDR corrected) (Figure 3).
OCD and SZ patients showed distinct alternations of brain functional dynamics.
Environmental hypoxia exposure causes fertility problems in human and animals. Compelling evidence suggests that chronic hypoxia impairs spermatogenesis and reduces sperm motility. However, it is unclear whether paternal hypoxic exposure affects fertilization and early embryo development. In the present study, we exposed male mice to high altitude (3200 m above sea level) for 7 or 60 days to evaluate the effects of hypoxia on sperm quality, zygotic DNA methylation and blastocyst formation. Compared with age-matched controls, hypoxia-treated males exhibited reduced fertility after mating with normoxic females as a result of defects in sperm motility and function. Results of in vitro fertilization (IVF) experiments revealed that 60 days’ exposure significantly reduced cleavage and blastocyst rates by 30% and 70%, respectively. Immunohistochemical staining of pronuclear formation indicated that the pronuclear formation process was disturbed and expression of imprinted genes was reduced in early embryos after paternal hypoxia. Overall, the findings of this study suggested that exposing male mice to hypoxia impaired sperm function and affected key events during early embryo development in mammals.
Alligatorweed [Alternanthera philoxeroides (Mart.) Griseb.] is an invasive semiaquatic weed that poses a serious threat to agricultural production and ecological balance worldwide. However, information about genetic factors associated with the adaptation and invasion mechanisms of this species is limited. Screening for appropriate reference genes is important for gene expression and functional analysis research in A. philoxeroides. In this study, 30 candidate genes that showed stable expression in different A. philoxeroides tissues under various treatments in RNA-seq data were chosen to design quantitative real-time PCR (qRT-PCR) primers. After the amplification specificity validation, 25 candidates were selected and further evaluated in a diverse set of A. philoxeroides samples, including leaf, stem, and root tissues under drought, salinity, heat, chilling, five herbicides, and corresponding untreated controls using qRT-PCR. The delta-CT method, geNorm, NormFinder, BestKeeper, and RefFinder algorithms were used to identify stable reference genes from A. philoxeroides samples. Overall, CoA, RFI2, Tubby, SRP19, and V-ATPase were the top five ideal reference genes in all organs and conditions. Tubby and CoA were the most stable reference genes in the leaf/stem; and RFI2, ERprr, and SPR19 were suitable reference genes for the roots. This work provided a foundation for exploring gene expression profiling of A. philoxeroides, especially those adaptation- and invasion-related genes, which may help in management of this invasive weed.
Understanding people’s perception of community resilience to disaster is important. This study explores the correlations of household livelihood assets, the adopted household disaster preparedness activities, and individuals’ assessment of community resilience.
The data was collected in 2018 by surveying a group of survivors affected by the 2008 Wenchuan earthquake in China. The CART (Community Advancing Resilience Toolkit) was used to measure individuals’ perception of community resilience, while the livelihood assets included financial, physical, natural, human, and social capitals owned by the family, and the preparedness contained 13 activities. Ordinary least squares (OLS) regression models were used to test our hypotheses.
Social capital is consistently and positively associated with the overall individuals’ perceived community resilience, while the natural, human, and financial capitals’ effects are not significant. The awareness and participation preparedness activities are positively correlated with the perceived community resilience, but the material preparedness activities are not.
Social capital and disaster preparedness activities are critical in building community resilience. Community resilience can be achieved by making the community more connected and by providing disaster preparedness interventions.
There is increasing evidence that blood oxygenation level-dependent signaling in white matter (WM) reflects WM functional activity. Whether this activity is altered in schizophrenia remains uncertain, as does whether it is related to established alterations of gray matter (GM) or the microstructure of WM tracts.
A total of 153 antipsychotic-naïve schizophrenia patients and 153 healthy comparison subjects were assessed by resting-state functional magnetic resonance imaging, diffusion tensor imaging, and high-resolution T1-weighted imaging. We tested for case–control differences in the functional activity of WM, and examined their relation to the functional activity of GM and WM microstructure. The relations between fractional anisotropy (FA) in WM and GM–WM functional synchrony were investigated as well. Then, we examined the associations of identified abnormalities to age, duration of untreated psychosis (DUP), and symptom severity.
Schizophrenia patients displayed reductions of the amplitude of low-frequency fluctuations (ALFF), GM–WM functional synchrony, and FA in widespread regions. Specifically, the genu of corpus callosum not only had weakening in the synchrony of functional activity but also had reduced ALFF and FA. Positive associations were found between FA and functional synchrony in the genu of corpus callosum as well. No significant association was found between identified abnormalities and DUP, and symptom severity.
The widespread weakening in the synchrony of functional activity of GM and WM provided novel evidence for functional alterations in schizophrenia. Regarding the WM function as a component of brain systems and investigating its alternation represent a promising direction for future research.
A series of new synthetic armored cables were developed and tested to ensure that they were suitable for use with the RECoverable Autonomous Sonde (RECAS), which is a newly designed freezing-in thermal ice probe. The final version of the cable consists of two concentric conductors that can be used as the power and signal lines. Two polyfluoroalkoxy jackets are used for electrical insulation (one for insulation between conductors, and the other for insulation of the outer conductor). The outer insulation layer is coated by polyurethane jacket to seal the connections between the cable and electrical units. The 0.65 mm thick strength member is made from aramid fibers woven together. To hold these aramid fibers in place, a sheathing layer was produced from a polyamide fabric cover net. The outer diameter of the final version of the cable is ~6.1 mm. The permissible bending radius is as low as 17–20 mm. The maximal breaking force under straight tension is ~12.2 kN. The cable weight is only ~0.061 kg m−1. The mechanical and electrical properties and environmental suitability of the cable were determined through laboratory testing and joint testing with the probe.
To investigate the effects of dietary fibre on follicular atresia in pigs fed a high-fat diet, we fed thirty-two prepubescent gilts a basal diet (CON) or a CON diet supplemented with 300 g/d dietary fibre (fibre), 240 g/d soya oil (SO) or both (fibre + SO). At the 19th day of the 4th oestrus cycle, gilts fed the SO diet showed 112 % more atretic follicles and greater expression of the apoptotic markers, Bax and caspase-3, and these effects were reversed by the fibre diet. The abundance of SCFA-producing microbes was decreased by the SO diet, but this effect was reversed by fibre treatment. Concentrations of serotonin and melatonin in the serum and follicular fluid were increased by the fibre diet. Overall, dietary fibre protected against high fat feeding-induced follicular atresia at least partly via gut microbiota-related serotonin–melatonin synthesis. These results provide insight into preventing negative effects on fertility in humans consuming a high-energy diet.
The Antarctic subglacial drilling rig (ASDR) is designed to recover 105 mm-diameter ice cores up to 1400 m depth and 41.5 mm-diameter bedrock cores up to 2 m in length. In order to ensure safe and convenient drilling, drilling auxiliaries are designed to support fieldwork and servicing. These auxiliaries are subdivided into several systems for power supply, drill tripping in the borehole, ice core and chip processing, and drill servicing and maintenance. The required equipment also includes two generators, a drilling winch with a cable, logging winch with a cable, control desk, pipe handler with a fixed clamp, chip chamber vibrator, centrifuge, emergency devices and fitting and electrical tools. Additionally, several environmental protective measures such as a new liquid-tight casing with a thermal casing shoe and a bailing device for recovering drilling fluid from the borehole were designed. Most of the auxiliaries were tested during the summer of 2018–2019 near Zhongshan Station, East Antarctica while drilling to the bedrock to a depth of 198 m.
Drilling to the bedrock of ice sheets and glaciers offers unique opportunities for examining the processes occurring in the bed. Basal and subglacial materials contain important paleoclimatic and paleoenvironmental records and provide a unique habitat for life; they offer significant information regarding the sediment deformation beneath glaciers and its effects on the subglacial hydraulic system and geology. The newly developed and tested Antarctic subglacial drilling rig (ASDR) is designed to recover ice and bedrock core samples from depths of up to 1400 m. All of the drilling equipment is installed inside a movable, sledge-mounted, temperature-controlled and wind-protected drilling shelter and workshop. To facilitate helicopter unloading of the research vessel, the shelter and workshop can be disassembled, with individual parts weighing <2–3 tons. The entire ASDR system weighs ~55 tons, including transport packaging. The ASDR is designed to be transported to the chosen site via snow vehicles and would be ready for drilling operations within 2–3 d after arrival. The ASDR was tested during the 2018–2019 summer season near Zhongshan Station, East Antarctica. At the test site, 2-week drilling operations resulted in a borehole that reached bedrock at a depth of 198 m.
A new, modified version of the cable-suspended Ice and Bedrock Electromechanical Drill (IBED) was designed for drilling in firn, ice, debris-rich ice and rock. The upper part of the drill is almost the same for all drill variants and comprises four sections: cable termination, a slip-ring section, an antitorque system and an electronic pressure chamber. The lower part of the IBED comprises an auger core barrel, reamers, a core barrel for ice/debris-ice drilling and a conventional geological single-tube core barrel or custom-made double-tube core barrel. First, the short and full-scale field versions of the IBED were tested at an outdoor testing stand and a testing facility with a 12.5 m-deep ice well. Then, in the 2018–2019 summer season, the IBED was tested in the field at a site ~12 km south of Zhongshan Station, East Antarctica, and a ~6 cm bedrock core was recovered from a 198 m-deep borehole. A total of 18 d was required to penetrate the ice sheet. The retrieved core samples of blue ice, basal ice and bedrock provided valuable information regarding the Earth's paleo-environment.
Major depressive disorder (MDD) is a prevalent mental disorder characterized by impairments in affect, behaviour and cognition. Previous studies have indicated that the anterior cingulate cortex (ACC) may play an essential role in the pathophysiology of depression. In this study, we systematically identified changes in functional connectivity (FC) for ACC subdivisions that manifest in MDD and further investigated the relationship between these changes and the clinical symptoms of depression.
Sub-regional ACC FC was estimated in 41 first-episode medication-naïve MDD patients compared to 43 healthy controls. The relationships between depressive symptom severity and aberrant FC of ACC subdivisions were investigated. In addition, we conducted a meta-analysis to generate the distributions of MDD-related abnormal regions from previously reported results and compared them to FC deficits revealed in this study.
In MDD patients, the subgenual and perigenual ACC demonstrated decreased FC with the posterior regions of the default network (DN), including the posterior inferior parietal lobule and posterior cingulate cortex. FC of these regions was negatively associated with the Automatic Thoughts Questionnaire scores and largely overlapped with previously reported abnormal regions. In addition, reduced FC between the caudal ACC and precuneus was negatively correlated with the Hamilton Anxiety Scale scores. We also found increased FC between the rostral ACC and dorsal medial prefrontal cortex.
Our findings confirmed that functional interaction changes in different ACC sub-regions are specific and associated with distinct symptoms of depression. Our findings provide new insights into the role of ACC sub-regions and DN in the pathophysiology of MDD.
This review involved 60 articles chosen from 336 empirical studies identified in five leading journals on the learning and teaching of Chinese as a second or foreign language in mainland China during the period 2014–2018. The selected studies document Chinese researchers' efforts to improve the teaching and learning of the Chinese language in terms of language pedagogy, language learning and teacher development. We contend that these studies on the teaching and learning of Chinese as a second or foreign language (CSL/CFL) can contribute to the advancement of second/foreign language education theories even though they were largely conducted to address local needs and interests in the Chinese context. Unfortunately, the impact of these studies on international language education research and pedagogical development remains limited and peripheral. For this reason, this review concludes with recommendations for Chinese researchers and journal editors in the field of Chinese language teaching and learning research on how to promote quality empirical research and enhance their contributions to second/foreign language education research.
An oral starch administration trial was used to evaluate glucose homoeostasis in grass carp (Ctenopharyngodon idella) and Chinese longsnout catfish (Leiocassis longirostris Günther). Fish were administered with 3 g of a water and starch mixture (with 3:2 ratio) per 100 g body weight after fasting for 48 h. Fish were sampled at 0, 1, 3, 6, 12, 24 and 48 h after oral starch administration. In grass carp, plasma levels of glucose peaked at 3 h but returned to baseline at 6 h. However, in Chinese longsnout catfish, plasma glucose levels peaked at 6 h and returned to baseline at 48 h. The activity of intestinal amylase was increased in grass carp at 1 and 3 h, but no significant change in Chinese longsnout catfish was observed. The activity of hepatic glucose-6-phosphatase fell significantly in grass carp but change was not evident in Chinese longsnout catfish. The expression levels and enzymic activity of hepatic pyruvate kinase increased in grass carp, but no significant changes were observed in the Chinese longsnout catfish. Glycogen synthase (gys) and glycogen phosphorylase (gp) were induced in grass carp. However, there was no significant change in gys and a clear down-regulation of gp in Chinese longsnout catfish. In brief, compared with Chinese longsnout catfish, grass carp exhibited a rapid increase and faster clearance rate of plasma glucose. This effect was closely related to significantly enhanced levels of digestion, glycolysis, glycogen metabolism and glucose-induced lipogenesis in grass carp, as well as the inhibition of gluconeogenesis.