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Al2O3 and honeycomb skeleton-Al2O3 composite coatings on Titanium alloy (Ti–6Al–4V) were prepared by atmospheric plasma spraying. A laser ablation experiment on as-sprayed coatings was performed. In this paper, the laser damage resistance, microstructure, phase composition of Al2O3 coatings were examined. 3D Dimensional Confocal Microscopy, Scanning Electron Microscopy (SEM), X-ray Diffraction (XRD), and Energy Dispersive Spectrometry (EDS) characterized the laser damage morphology, microstructure, phase composition, and element analysis, respectively. The influence of the honeycomb skeleton on the laser ablation damage on as-sprayed coatings was investigated by a comparative analysis of the laser damage morphology with different laser ablation times and gas flow. The results show that the honeycomb skeleton raises thermal conductivity and thermal diffusivity. Moreover, a “tower”-like dendrite was generated during the laser irradiation of the composite coating. The honeycomb skeleton refined the structure, suppressed crack propagation, and reduced the influence of gas flow on cracks. Under the same experimental laser ablation parameters, the laser damage area of the honeycomb skeleton-Al2O3 composite coating was smaller than that of the Al2O3 coating. It was demonstrated that the laser damage resistance of the honeycomb skeleton-Al2O3 composite coating was superior to that of the Al2O3 coating.

To explore the genetic basis for a Chinese patient with congenital disorders of glycosylation-If (CDG-If).Whole exome sequencing (WES) was carried out for the patient.The patient, a 5-year-old girl, has featured severe mental retardation. She had learned to walk at 4 years old and was only able to make sounds like "ma ma" occasionally. She was found to harbor compound heterozygous variants of the MPDU1 gene, namely c.389GA and c.470TC, both of which were unreported previously.Above finding has enriched the mutational spectrum of CDG-If among the Chinese population, with c.218GA being the commonest mutation, along with a more severe phenotype.

To uncover the chewing mechanism of Cyrtotrachelus buqueti Guer, a mathematical model was created and a kinematic analysis of its rostrum mouthparts was conducted for, to our knowledge, the first time. To reduce noise and improve the quality of scanning electron micrographs of the weevil's mouthparts, nonlocal means and integral nonlocal means algorithms were proposed. Additionally, based on a comparison and analysis of five classical edge detection algorithms, a multiscale edge detection algorithm based on the B-spline wavelet was used to obtain the boundaries of structural features. The least squares method was used to analyze the data of the mouthparts to fit the mathematical model and fitted curves were obtained using Gaussian equations. The results show that curvature and concave–convex variations of the weevil's mouthparts can highlight fluctuations in friction effects when it chews bamboo shoots, which is helpful in preventing debris from bamboo shoots or other debris from sticking to the mouthpart surfaces. Moreover, this paper highlights the utility of micro-computed tomography (microCT) for three-dimensional (3D) reconstruction and a flowchart is suggested. The reconstructed slices were 9.0 μm thick and an accurate 3D rendered model was obtained from a series of microCT slices. Finally, a real model of the rostrum mouthparts was analyzed using finite-element analysis. The results provide a biological template for the design of a novel bionic drilling mechanism.

A magnesium alloy was subjected to strengthening treatment by coupling cavitation bubbles with Al2O3 nanoparticles. The samples were strengthened by embedding Al2O3 nanoparticles with the energy generated by cavitation-bubble collapse, following which a strengthening model was established to perform test verification. The result showed that, after experiencing the combined effect for 5 min, nanoparticles appear on the sample surface, observed under the scanning electron microscope (SEM); by applying the X-ray diffractometer (XRD) and X-ray photoelectron spectrometer (XPS), it is found that the Al2O3 content increases, implying that Al2O3 particles have been embedded in the sample surface. The microhardness of the samples improves by 36 %. In terms of the strengthening mechanism under the combined effect, the energy generated due to cavitation-bubble collapse is transferred to the Al2O3 particles to enable them to strike the sample surface. Thus, the samples have a more gentle impact, and the transition zone with pits formed on the sample surface is significantly smoother and more continuous. Moreover, the samples are further strengthened after Al2O3 nanoparticles are embedded within the sample surface, as these nanoparticles present high strength and microhardness. However, with the increasing duration of the strengthening process, the failure characteristics of surface morphologies of the samples gradually develop; after experiencing the combined effect for 10 min, a large area of the surface is damaged. XRD and XPS results indicate that Al2O3 particles induce a decrease in the binding capacity with the surface layer of the samples and thus gradually separate from the samples. Therefore, the properties of the samples are adversely affected.

To uncover the chewing mechanism of Cyrtotrachelus buqueti Guer, a mathematical model was created and a kinematic analysis of its rostrum mouthparts was conducted for, to our knowledge, the first time. To reduce noise and improve the quality of scanning electron micrographs of the weevil's mouthparts, nonlocal means and integral nonlocal means algorithms were proposed. Additionally, based on a comparison and analysis of five classical edge detection algorithms, a multiscale edge detection algorithm based on the B-spline wavelet was used to obtain the boundaries of structural features. The least squares method was used to analyze the data of the mouthparts to fit the mathematical model and fitted curves were obtained using Gaussian equations. The results show that curvature and concave-convex variations of the weevil's mouthparts can highlight fluctuations in friction effects when it chews bamboo shoots, which is helpful in preventing debris from bamboo shoots or other debris from sticking to the mouthpart surfaces. Moreover, this paper highlights the utility of micro-computed tomography (microCT) for three-dimensional (3D) reconstruction and a flowchart is suggested. The reconstructed slices were 9.0 μm thick and an accurate 3D rendered model was obtained from a series of microCT slices. Finally, a real model of the rostrum mouthparts was analyzed using finite-element analysis. The results provide a biological template for the design of a novel bionic drilling mechanism.

To determine the carrier rate of deafness-related genetic variants among 53 873 newborns from Zhengzhou.Heel blood samples of the newborns were collected with informed consent from the parents, and 15 loci of 4 genes related to congenital deafness were detected by microarray.In total 2770 newborns were found to carry deafness-related variants, with a carrier rate of 5.142%. 1325 newborns (2.459%) were found to carry heterozygous variants of the GJB2 gene, 1071 (1.988%) were found with SLC26A4 gene variants, 205 were found with GJB3 gene variants (0.381%), and 120 were found with 12S rRNA variants (0.223%). Five newborns have carried homozygous GJB2 variants, two have carried homozygous SLC26A4 variants, five have carried compound heterozygous GJB2 variants, and four have carried compound heterozygous SLC26A4 variants. 33 neonates have carried heterozygous variants of two genes at the same time.The carrier rate of deafness-related variants in Zhengzhou, in a declining order, is for GJB2, SLC26A4, GJB3 and 12S rRNA. The common variants included GJB2 235delC and SLC26A4 IVS7-2AG, which are similar to other regions in China. To carry out genetic screening of neonatal deafness can help to identify congenital, delayed and drug-induced deafness, and initiate treatment and follow-up as early as possible.

Microstructural response of AISI 316L stainless steel to laser peening (LP) was examined by means of optical microscopy (OM) and transmission electron microscopy (TEM) in order to analyze the effects of LP on hydrogen-induced cracking (HIC) resistance. Depth profiles of near-surface microhardness and surface compressive residual stress (CRS) of LP treated specimens were presented respectively. Slow strain rate tensile tests were performed on the hydrogen-charged samples and their corresponding stress-strain curves as well as fracture morphologies were finally investigated in detail. The results demonstrated that LP induced a grain refinement effect on the treated surface while a maximum refining rate of 56.18% was achieved at the laser power density of 10 GW/cm2. The near-surface microhardness also exhibited an attenuation trend with the increasing depth. The surface CRS positively correlated with power density before it reached a threshold value. A special U-shaped dislocation tangle band was observed in the LP treated specimen which served as hydrogen trapping sites. The LP treated samples exhibited better toughness after hydrogen charging from both macro mechanical properties and micro fracture morphologies. LP-induced grain refinement and CRS are believed to be the main contributing factors towards inhibiting the diffusion of hydrogen atoms which ultimately leads to the reduction of the hydrogen embrittlement sensitivity of AISI 316L stainless steel.

To solve the dynamic problem of different activities in human activity recognition research, an activity recognition method based on a multiplex limited penetrable visibility graph is proposed. The 21 pressure values for each sampling are mapped to nodes in the first-layer network; then the average path length of nodes in the asynchronous periodic network is obtained, and the second-layer network used to explore different activities is built. Finally, the characteristic parameters and dynamic characteristics of different activities are explored and analyzed. The experimental results demonstrate that through the joint distribution of the average clustering coefficient and the maximum degree parameter of the node, the discrimination problems of different postures can be better realized, and it has good adaptability. It provides a new approach to gait recognition research that can be used in medical clinical diagnosis, rehabilitation training, and public health.

Laser cladding technologies has received wide attention since its low dilution and high deposition efficiency. However, the high cooling rate and the temperature gradient due to the rapid heating and cooling characteristic could cause excessive thermal stress and even crack in the coating. In this paper, a dynamic preheating method, in which an additional heat source is applied to heat the localized region ahead of the moving molten pool, was proposed with the intent of solving these problems. A three-dimensional finite element model was established to explore the effect of the dynamic preheating on the thermal behavior of the multi-track and multi-layer laser cladding. The laser cladding experiment was performed to verify the accuracy of the heat transfer model. The simulated thermal cycle curves are in agreement with the experimental thermal history. The calculated results show that the temperature gradient in the depth direction and the cooling rate decrease with the increasing layers. The appropriate process parameter, such as thermal flux density, interaction time, and preheating distance leads to the decrease of the cooling rate and the maximum temperature gradient. Thus it is illustrated that dynamic preheating is contributed to the reduction of the thermal stress and the cracking probability.

Ni-based WC coatings were successfully fabricated on Ti6Al4V titanium alloy substrate by the air plasma spraying (APS) process. The as-sprayed coatings were remelted with a continuous wave CO2 laser. The coatings were characterized using a scanning electron microscope (SEM), an energy dispersive spectrometer (EDS), an X-ray diffractometer (XRD), a Vickers microhardness tester, a ball-on-disc friction and wear tester, and a 3D measuring laser microscope. The results indicated that the laser-remelted coatings possessed a more homogeneous microstructure and lower porosity, were more dense, and bonded well with the substrate. The lamellar structure and microcracks of the as-sprayed coatings were eliminated after laser remelting. The average porosity markedly decreased to 1.3% from 9.7% of the as-sprayed coating. Many needle dendrites grew outward from the dissolution surface of the WC, while massive precipitates abundantly appeared around and away from the WC particles. The microhardness of the laser-remelted coating was enhanced to 884.7–1363.3 HV0.3, which was much higher than that of the as-sprayed coatings and nearly three times higher than that of the substrate. Under the same load, the wear volume of the substrate was nearly 13 times higher than that of the laser-remelted coating and five times higher than that of the as-sprayed coating. The wear mechanism of the laser-remelted coating and the as-sprayed coating was mainly abrasive wear; however, the wear mechanisms of the substrate were a combination of adhesive wear, micro-cutting, and delamination wear.

Objective To investigate the risk factors for early miscarriage among Chinese women. Design Hospital-based matched case-control study. Setting Academic medical center and maternal health hospital. Patient(s) 620 women with early miscarriage (less than 13 weeks of gestation) and 1,240 normal pregnant women. Intervention(s) Face-to-face questionnaire. Main Outcome Measure(s) Multivariable conditional odds ratio (OR) and 95% confidence interval (CI) to measure risk factors. Result(s) After adjustment for confounding factors, the following were independently associated with increased risk: history of miscarriage, repeated induced abortion, working night shifts, and frequent staying up late. Vitamin supplementation and regular physical activity reduced the risk of miscarriage. We did not find paternal age, alcohol consumption, or smoking status to be linked with early miscarriage. Conclusion(s) Our findings suggest that a healthy diet, regular physical activity, and planned pregnancy may be advantageous for women in pre-pregnancy or early pregnancy. Induced abortion, working night shifts, and frequent staying up late were associated with an increased risk of miscarriage. Further work in larger populations is warranted.

To investigate the effect and safety of dexmedetomidine applied for patient-controlled sedation under combined spinal anesthesia. 150 cases who would be implemented lower limbs operations were randomly divided into patient-controlled sedation group (Group PCS) and control group (Group C) and 75 cases for each group. The ages of patients were between 18 and 65 years old and patients were with American Society of Anesthesiologists (ASA) or level. After being implemented combined spinal anesthesia, patients of Group PCS were undergone patient-controlled sedation by using dexmedetomidine (4μg/mL) with 2mL of load quantity, 1.5ml of background infusion quantity, 0.5mL of single dose and 20s of locking time; patients of Group C were constantly infused the normal saline at the rate of 10ml/h by pump injection. HR, MAP, SpO2, Ramsay sedation scores and airway scores before the pump injection (T0), 10 min (T1), 3 min (T2), 5 min (T3), 7min (T4) and 10min (T5) after the pump injection, at the beginning of operations (T6), 10min(T7) after the operations and in the end of operations (T8) of patients of two groups were respectively recorded. At the same time, the pressing numbers and doses of dexmedetomidine of patients of Group PCS were observed. Compared with the HR at T0, HR in Group PCS obviously decreased between T1 and T8 (P0.05). Compared with HR in Group C, HR in Group PCS obviously slowered between T1 and T8 (P0.05). Compared with the MAP at T0, MAP in Group PCS gradually increased between T1 and T3 and gradually reduced between T5 and T8 (P0.05). MAP between T5 and T8 in Group PCS were significantly lower than those in Group C (P0.05). Between T3 and T7, there were 51, 72, 74, 73, 72 patients in Group PCS whose Ramsay scores were from 3 to 4 points respectively. During the process of patient-controlled sedation of patients in Group PCS, the pressing times were 112.10±65. 79 times. The effective pressing numbers were 21.00±9. 07times. The patient-controlled dosages were (15.12±3.19) ml; The dosages were 11.29±2.16ml when the level of sedation achieved 3 to 4 scores in Ramsay sedation scores; And the required time to achieve 3 to 4 scores in Ramsay sedation scores was 7.55±1.53 min. In the lower limbs operations, the usage of dexmedetomidine applied for patient-controlled sedation under combined spinal anesthesia can effectively approach to the personalized medicine and is effective in clinical application.

To investigate if women with subclinical hypothyroidism (SCH), positive thyroid gland peroxidase antibody (TPOAb) in early pregnancy accepted treatment or not had effect on perinatal outcomes.15 000 pregnant women who delivered in Women and Infants Hospital of Zhengzhou from January 1, 2013 to June 30, 2014 were recruited retrospectively. Among them, 2 042 women had SCH in early pregnancy. The diagnostic standard of SCH was serum free thyroxine (FT4) between 12.91-22.35 pmol/L and TSH level between 5.22-10.00 mU/L. TPOAb level ≥ 34 U/L was defined as positive result. The 2 042 patients with SCH were divided into the treated group (1 236 cases) and the untreated group (806 cases), according to whether or not women accepted the levothyroxine treatment. Meanwhile, the 2 042 patients with SCH were divided into the TPOAb (+) treated group (1 021 cases), the TPOAb (+) untreated group (201 cases), the TPOAb (-) treated group (215 cases) and the TPOAb (-) untreated group (605 cases), according to the TPOAb result and acceptance the levothyroxine treatment. 2 000 pregnant women with normal thyroid function who delivered in the same period were selected as the control group. Perinatal outcomes were analyzed.(1) The incidence of SCH in early pregnancy was 13.61% (2 042/15 000). 60.53% (1 236/2 042) accepted levothyroxine treatment and 39.47% (806/2 042) did not. (2) The incidence of abortion (5.71%, 46/806), premature delivery (6.20%, 50/806), gestational hypertension disease (13.90%, 112/806), gestational diabetes mellitus (GDM; 6.58%, 53/806), fetal growth restriction (FGR; 12.28%, 99/806) and low birth weight infants (10.17%, 82/806) in the untreated group were higher than those in the treated group [3.96% (49/1 236), 4.21% (52/1 236), 10.76% (133/1 236), 4.13% (51/1 236), 8.90% (110/1 236), 7.52% (93/1 236), respectively] and the control group [3.60% (72/2 000), 4.00% (80/2 000), 10.70% (214/2 000), 3.80% (76/2 000), 9.60% (192/2 000), 7.50% (150/2 000), respectively]. The differences were statistically significant (P0.05). While there was no statistically significant difference in the incidence of placental abruption, anemia in pregnant women, or fetal distress among the three groups (P0.05). (3)The incidences of abortion (11.44%, 23/201), premature delivery (12.44%, 25/201), gestational hypertension disease (22.89%, 46/201), GDM (8.46%, 17/201), FGR (19.90%, 40/201) and low birth weight infants (16.42%, 33/201) in the TPOAb (+) untreated group were higher than those in TPOAb (+) treated group [4.02% (41/1 021), 4.21% (43/1 021), 10.77% (110/1 021), 4.11% (42/1 021), 8.72% (89/1 021), 7.35% (75/1 021), respectively] and the control group, with statistically significant differences (P0.05). The incidence of the pregnancy complications in the TPOAb (+) treated group was higher than those in the control group, but the differences were not statistically significant (P0.05). (4) There were no statistically significant difference (P0.05) in the incidence of abortion (3.72%, 8/215), premature delivery (4.19%, 9/215), gestational hypertension disease (10.70%, 23/215), GDM (4.19%, 9/215), FGR (9.77%, 21/215) or low birth weight infants (8.37%, 18/215) among the TPOAb (-) treated group, the TPOAb (-) untreated group [3.80% (23/605), 4.13% (25/605), 10.91% (66/605), 5.95% (36/605), 9.75% (59/605), 8.10% (49/605), respectively] and the control group.(1) The incidence of abortion, premature delivery, gestational hypertension disease, GDM, FGR and low birth weight infants could be increased in women with SCH in early pregnancy. (2) Thyroxine treatment could reduce the incidence of pregnancy complications in women with SCH in early pregnancy.

An adjustable foaming machine that consisted of air feeding system, liquid feeding system, foaming device, and control system was designed to satisfy various demands on foam density and foam diameter in the preparation of foam concrete. The air-liquid ratio was adjusted by controlling the foaming liquid flow, and the adjustment of foam density was achieved. An adjustable single-foam tube structure was adopted to realize the controls of foam density and pore size by adjusting the packing density of the foaming medium in the foaming tube. By using the single chip as the digital processing core, the communication between single chip and frequency converter was established through the RS485 interface, thereby realizing the automatic control in the working process of the adjustable foaming machine. The experimental result indicated that the foaming process of this machine was stable and highly efficient, and foam density and foam diameter were easy to adjust and control, which improved the usability.

Aiming at the measurement of cement rotary kiln’s axis, the paper presents the design method of a wireless dynamic measurement system for rotary kiln’s axis. A wireless sensor network monitoring system that can collect multiple parameters was designed, which integrates the detection functions for kiln shell axis deviation, kiln tire axis deviation and drive gear synchronizing signal, and has the advantages of wireless transmission, low power consumption, and easy to install. ZigBee tree network was developed, which is beneficial to expand the capacity of wireless network, improve the efficiency of data transmission, reduce the cost, and shorten the development cycle. The sever measurement software was designed, which has the functions of data wireless acquisition and analysis for rotary kiln axis. The related prototypes of the monitoring device were developed, which verified the effectiveness of the system on the cement rotary kiln．