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Background:. Twin pregnancies continue to increase worldwide; however, the current clinical prenatal evaluation for the intrauterine growth of twins still relies on the growth standards of singletons. We attempted to establish a set of fetal biometric references for Chinese twin pregnancies, stratified by chorionicity and conception mode as spontaneously conceived monochorionic diamniotic (SC-MCDA), spontaneously conceived dichorionic diamniotic (SC-DCDA), and assisted reproductive technology dichorionic diamniotic (ART-DCDA) twins. Methods:. From 2016 to 2019, the ultrasonographic fetal biometric measurements were longitudinally collected in pregnant women, including fetal weight, biparietal diameter, head circumference, abdominal circumference, femur length, and humerus length. The linear mixed models were used to test the difference of growth patterns between groups, and the growth curve of each biometric parameter was modeled by a generalized additive model for location scale and shape. Results:. A total of 929 twin pregnant women and 2019 singleton pregnant women, met the inclusion criteria. Among twin pregnancies, 148 were SC-MCDA, 215 were SC-DCDA, and 566 were ART-DCDA twins. Overall, SC-DCDA twins grew faster than SC-MCDA twins, while slower than ART-DCDA twins (all P

In this study, a monochromatic GaN-based micro-light-emitting-diode (µLED) array was fabricated using flip-chip technology. The laser lift-off (LLO) process was employed to decrease the light divergence caused by the differing refractive indexes of sapphire (n = 1.77) and GaN (n = 2.4). The LLO-µLEDs considerably improve light collimation, compared with conventional flip-chip µLEDs containing a sapphire substrate. We highlight, in particular, the importance of the optical characteristics before and after LLO. Collimation of light was discovered to be 12% higher after removal of the sapphire substrate. The results are of high importance for understanding the optical properties of µLED arrays after LLO. Keywords: GaN, Light-emitting diodes, Laser lift-off, Micro-LEDs

ObjectivesTo identify obstetrical subgroups in which (1) the caesarean delivery (CD) rate may be reduced without compromising safety and (2) CD may be associated with better perinatal outcomes.DesignA multicentre cross-sectional study.Setting19 hospitals in the USA that participated in the Consortium on Safe Labor.Participants228 562 pregnant women in 2002–2008.Main outcome measuresMaternal and neonatal safety was measured using the individual Weighted Adverse Outcome Score.MethodsWomen were divided into 10 subgroups according to a modified Robson classification system. Generalised estimated equation model was used to examine the relationships between mode of delivery and Weighted Adverse Outcome Score in each subgroup.ResultsThe overall caesarean rate was 31.2%. Repeat CD contributed 29.5% of all CD, followed by nulliparas with labour induction (15.3%) and non-cephalic presentation (14.3%). The caesarean rates in induced nulliparas with a term singleton cephalic pregnancy and women with previous CD were 31.6% and 82.0%, respectively. CD had no clinically meaningful association with perinatal outcomes in most subgroups. However, in singleton preterm breech presentation and preterm twin gestation with the first twin in non-cephalic presentation, CD was associated with substantially improved maternal and perinatal outcomes.ConclusionsWomen with repeat CD, term non-cephalic presentation, term twins or other multiple gestation and preterm births may be the potential targets for safely reducing prelabour CD rate, while nulliparas or multiparas with spontaneous or induced labour, women with repeat CD, term non-cephalic presentation, term twins or other multiple gestation and preterm births are potential targets for reducing intrapartum CD rate without compromising maternal and neonatal safety in the USA. On the other hand, CD may still be associated with better perinatal outcomes in women with singleton preterm breech presentation or preterm twins with the first twin in non-cephalic presentation.

Aims. The study is aimed at studying the incidence of acute kidney injury (AKI) and exploring the potential predictor for AKI in patients with acute pancreatitis. Methods. A retrospective study adopting a stratified cohort sampling design was performed in a cohort of patients (n=237) diagnosed with acute pancreatitis without any renal injury. The following information including age, gender, serum creatinine, serum urea nitrogen, serum uric acid, serum cystatin C, fasting serum glucose, serum amylase, serum lipase, serum choline esterase, total protein, albumin, globulin, total bilirubin, direct bilirubin, total bile acids, glutamic-pyruvic transaminase, glutamic-oxaloacetic transaminase, gamma glutamyl transpeptidase, and alkaline phosphatase were collected from each patient when they were diagnosed with acute pancreatitis. Student t-test was conducted to figure out the difference between patients with and without AKI. Univariate and multivariate logistic regression analyses were used for investigating the predictors for AKI in patients with acute pancreatitis. Results. 18 (7.6%) patients in total had developed AKI among the study group. Compared with patients without AKI (1.01 ± 0.26 mg/L), the level of baseline serum cystatin C (CYS-C) was significantly higher in patients with AKI (3.64 ± 2.17 mg/L, P<0.001). Baseline serum CYS-C (OR=203.594, P<0.001) was the independent and significant predictor for AKI in patients with acute pancreatitis. AKI in patients with acute pancreatitis could be identified with a sensitivity of 88.9% at specificity of 100% (AUC=0.948, 95% CI 0.879–1.000) by baseline serum CYS-C (cut-off value = 1.865 mg/L). Conclusions. Baseline serum CYS-C shall be adopted to predict the potential risk of AKI in patients with acute pancreatitis.

For the actual situation in Liaoning Power Grid, analyzed the problems the wind power interconnection brought. Involving power quality, power fluctuations, power peaking, power delivery and so on. Proposed related coping strategies. Strengthen wind power connection management, plan the power structure scientifically and rationally, carry out multi-channel consumer of wind power actively, improve the security and stability level of the power grid.

Aim to the traditional acceleration gesture recognition system on PC platform had the problem of high power consumption, hard to carry and low recognition rate, the paper proposes a novel gesture recognition algorithm. The algorithm first sampled the gestures signal acceleration by acceleration sensor, and then segmented and smoothing filtered the collected original signal. After preprocessing, extracted the feature value and segmented the feature value according to segments signal energy. Finally for all the segments used the improved DTW(Dynamic Time Warping) algorithm[1] to match the extracted signal features with the predefined template feature respectively and integrated the matching results of them, then concluded the final recognition results. We apply the proposed algorithm to the smartphone and test the system. Testing result shows that: The novel algorithm can improve the recognition rate and enable the system to real-time and accuracy recognizes gestures.

Endothelial progenitor cells (EPCs) play a key role in tissue repair and regeneration. Previous studies have shown a positive correlation between the number of circulating EPCs and clinical outcomes of patients with traumatic brain injury (TBI). A recent study has further shown that intravenous infusion of human umbilical cord blood-derived endothelial colony-forming cells (ECFCs) improves outcomes of mice subjected to experimental TBI. This follow-up study was designed to determine whether intracerebroventricular (i.c.v.) infusion of ECFCs, which may reduce systemic effects of these cells, could repair the blood–brain barrier (BBB) and promote angiogenesis of mice with TBI. Adult nude mice were exposed to fluid percussion injury and transplanted i.c.v. with ECFCs on day 1 post-TBI. These ECFCs were detected at the TBI zone 3 days after transplantation by SP-DiIC18(3) and fluorescence in situ hybridization. Mice with ECFCs transplant had reduced Evans blue extravasation and brain water content, increased expression of ZO-1 and claudin-5, and showed a higher expression of angiopoietin 1. Consistent with the previous report, mice with ECFCs transplant had also increased microvascular density. Modified neurological severity score and Morris water maze test indicated significant improvements in motor ability, spatial acquisition and reference memory in mice receiving ECFCs, compared to those receiving saline. These data demonstrate the beneficial effects of ECFC transplant on BBB integrity and angiogenesis in mice with TBI.

The expression levels of microRNAs (miRNAs) including miR-21, have been reported to change in response to traumatic brain injury (TBI), suggesting that they may influence the pathophysiological process in brain injury. To analyze the potential effect of miR-21 on neurological function after TBI, we employed the fluid percussion injury rat model and manipulated the expression level of miR-21 in brain using intracerebroventricular infusion of miR-21 agomir or antagomir. We found that upregulation of miR-21 level in brain conferred a better neurological outcome after TBI by improving long-term neurological function, alleviating brain edema and decreasing lesion volume. To further investigate the mechanism underlying this protective effect, we evaluated the impact of miR-21 on apoptosis and angiogenesis in brain after TBI. We found that miR-21 inhibited apoptosis and promoted angiogenesis through regulating the expression of apoptosis- and angiogenesis-related molecules. In addition, the expression of PTEN, a miR-21 target gene, was inhibited and Akt signaling was activated in the procedure. Taken together, these data indicate that miR-21 could be a potential therapeutic target for interventions after TBI.

For cooled 320 × 240 detector with staring focal plane array, a novel middle infrared athermal optical system is presented. The system is composed of 5 spherical lenses. The materials of lenses are silicon and germanium. The optical parameters and modulation transfer function (MTF) are investigated. The system has the diffraction limited image quality and stable image plane from −30 °C to 70 °C. The characteristic parameters of the system are as follows: f/number of 4, cold shield efficiency of 100%, spectrum region of 3.7–4.8 μm and transmissivity of 80%. The system has the merits of simple structure, low price, and it is easy to machining.

Background Endothelial progenitor cells (EPCs) are critical for repairing injured tissue. Endothelial colony-forming cells (ECFCs) are a homogeneous subtype of EPCs. We investigated whether intravenously infused human ECFCs homed to injured brain promoted angiogenesis and ameliorate neurologic disabilities in a mouse model of traumatic brain injury. Materials and methods ECFCs were generated by in vitro propagation of EPCs from human umbilical cord blood. Young female nude mice received intravenously ECFCs from human newborns (1 × 10 6 ) 1 h after they were exposed to lateral fluid percussion injury. Neurologic function was evaluated by a modified neurologic severity score and Morris water maze. ECFC homing and neovascularization at the site of injury were examined by fluorescence in situ hybridization and histochemistry on days 2 and 14 after injury, respectively. Results Donor ECFCs were detected in injured brain 24 h after infusion. The modified neurologic severity score and Morris water maze tests were used to evaluate neurologic disability, and found the rate of neurologic disability was improved in mice that received ECFCs. Microvessel density and expression of the proangiogenic growth factors stromal cell–derived factor-1 and vascular endothelial growth factor were also increased in the region of injured brain from mice that received ECFCs compared with those received vehicle control. Conclusions These data suggest that ECFCs are effective in promoting neovascularization and improving neurologic functions after traumatic brain injury.

Automatic image tagging seeks to assign relevant words to images that describe the actual content found in the images without intermediate manual annotation. One common problem shared by most previous learning approaches for automatic image tagging is that the segmented regions in the image were considered as equally important and were processed equally. The goal of this paper is to develop a novel annotation approach based on regions of interest to take into account the users' real experience and fix a visual weight for each region according to the degree of interest. To do this, we firstly segmented the image into several regions. And then it calculated the degree of interest for each region according to the experiments of human visual attention and cognitive psychology. Each region will be assigned a visual weight at the third step. We can obtain the prior probability of the region given the concept. At the stage of the automatic annotation, we can calculate posterior probability with the Bayesian Theorem to get the most likely concept to tag the unseen image. The proposed methodology is examined in a well-known benchmark image collection and the results demonstrated its competitiveness.

Background and objectives Co-sleeping (bed or room sharing) has potential implications for children's development. Previous studies showed that co-sleeping was more prevalent in non-Western countries than in Western countries, which demonstrated that co-sleeping was marked with ethnic and socio-cultural background characteristics. The purpose of this study was to survey the prevalence of bed and room sharing and to examine related factors among school-aged children in an Asian country – China. Methods A cross-sectional questionnaire survey was conducted in 10 districts of Shanghai, China from November to December 2005. A total of 4108 elementary school children, 49.2% boys and 50.8% girls with a mean age of 8.79 years, participated. Parent-administered questionnaires were used to collect information about children's sleeping arrangements and socio-demographic characteristics. Results The prevalence of routine bed sharing, room sharing and sleeping alone in Chinese school-aged children was 21.0%, 19.1% and 47.7%, respectively. Bed and room sharing didn't show significant gender difference but gradually decreased with increasing age. Multivariate logistic regression identified those factors associated with bed and room sharing: younger age, large family, children without their own bedroom and parents' approval of a co-sleeping arrangement. Conclusion Co-sleeping arrangement was a common practice in Chinese school-aged children. Associated factors were characterized by intrinsic socio-cultural values and socio-economic status in China.

This work proposes a hybrid temporal and spatial error concealment technique. We first present, in the temporal domain, an improved boundary match algorithm to recover lost motion vectors, and it preserves better edge continuity on the boundary of the recovered block. In our spatial error concealment, we reduce the high computational complexity of the method of the weighted Markov random field (MRF) to make it feasible in real applications. Finally we hybridize our temporal and spatial error concealments together. The hybrid criterion is based on the motion fields of the damaged frame and the similarities of two contiguous frames. Experimental results show that our proposed hybrid error concealment algorithm can provide good recovery of missing blocks.