Study on Erosion Behavior of Laser Wire Feeding Cladding High-Manganese Steel Coatings.

High-manganese steel (HMnS) coating was prepared using laser wire feeding cladding technology. Erosion damage behavior and erosion rate of both the HMnS coating and the HMnS substrate were investigated at room temperature using an erosion testing machine. SEM/EDS, XRD, EPMA, and microhardness analyses were used to characterize the cross sections of the coating and matrix, as well as the morphology, phase composition, and microhardness of the eroded surface. The phase composition, orientation characteristics, and grain size of the eroded surfaces of both the coating and substrate were examined by using the EBSD technique. The erosion mechanism under different erosion angles was revealed. By analyzing the plastic deformation behavior of the subsurface of the HMnS coating, the impact hardening mechanism of the high-manganese steel coating during the erosion process was investigated. The results demonstrated that the HMnS coating, prepared through laser wire feeding cladding, exhibited excellent metallurgical bonding with the substrate, featuring a dense microstructure without any cracks. The erosion rate of the coatings was lower than that of the substrate at different erosion angles, with the maximum erosion rate occurring at 35° and 50°. The damage to the coating and substrate under low-angle erosion was primarily attributed to the micro-cutting of erosion particles and a minor amount of hammering. At the 90° angle, the dominant factor was hammering. After erosion, the microhardness of both the coating and substrate sublayer increased to 380HV0.3 and 359HV0.3, respectively. Dendrite segregation, refined grains, low-angle grain boundaries, and localized dislocations, generated by laser wire feeding cladding, contributed to the deformation process of HMnS. These factors collectively enhance the hardening behavior of HMnS coatings, thereby providing excellent erosion resistance.

The impact of baseline calcified plaque volume on coronary rapid plaque progression by serial coronary computed tomography angiography in patients with type 2 diabetes.

OBJECTIVES: Patients with type 2 diabetes mellitus (T2DM) are susceptible to coronary artery disease (CAD), and coronary outcomes in these patients are heterogeneous. However, the impact of coronary plaque compositions on rapid plaque progression (RPP) in patients with T2DM has rarely been reported. This study aimed to investigate the association of coronary plaque compositions with rapid lesion volume progression in patients with T2DM. MATERIALS AND METHODS: A total of 159 subjects (aged 62.51 ± 10.3 years, 68.6% were male) who underwent serial coronary computed tomography angiography (CCTA) with type 2 diabetic status were enrolled. Annual change of plaque volume (PV) (mm3/year) was defined as PV change divided by inter-scan period. RPP was defined as the progression of plaque burden (PV divided by vessel volume multiplied by 100) ≥0.59%/year. Plaque components were compared between RPP and no RPP groups. Then all patients were divided into 3 groups according to the baseline calcified plaque volume tertiles. The outcome was whether RPP occurred. RESULTS: The median inter-scan period was 2.09 (range 1.41-3.33) years. The overall incidence of RPP was 61.0%. The calcified plaque volume decreased significantly in the RPP group as compared to the no RPP group. The risk of RPP (odds ratio [OR] 0.39; 95% confidence interval [CI]: 0.17-0.88; p = 0.024) was reduced in tertiles III as compared to that in tertiles I even after adjustment for baseline variables (OR 0.21; 95% CI: 0.07-0.63; p = 0.005). Moreover, adding the calcified plaque volume significantly raised the predictive value for the RPP (0.370, p = 0.030, and 0.059, p = 0.025, NRI, and IDI respectively) as compared to traditional factors. CONCLUSION: The baseline calcified plaque volume is an independent protective factor for the rapid progression of coronary atherosclerosis in patients with T2DM.

The calcified plaque volume of the coronary was significantly lower in T2DM subjects with RPP than in those without RPP.Higher levels of atherosclerotic calcification may have a protective value on plaque stabilization in patients with T2DM.Calcified plaque volume of the coronary should be considered when proposing risk stratification in T2DM patients.

[Genetic analysis of a Chinese patient with congenital disorders of glycosylation-If].

OBJECTIVE: To explore the genetic basis for a Chinese patient with congenital disorders of glycosylation-If (CDG-If). METHODS: Whole exome sequencing (WES) was carried out for the patient. RESULTS: 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.389G>A and c.470T>C, both of which were unreported previously. CONCLUSION: Above finding has enriched the mutational spectrum of CDG-If among the Chinese population, with c.218G>A being the commonest mutation, along with a more severe phenotype.

Mathematical model and nanoindentation properties of the claws of Cyrtotrachelus buqueti Guer (Coleoptera: Curculionidae).

Scanning electron microscopy (SEM) was used to observe the macroscopic, microscopic, and cross-sectional structures of the claws of Cyrtotrachelus buqueti Guer (Coleoptera: Curculionidae), and a mathematical model of a claw was used to investigate the structure-function relationships. To improve the quality of the SEM images, a non-local means (NLM) algorithm and an improved NLM algorithm were applied. After comparison and analysis of five classical edge-detection algorithms, the boundaries of the structural features of the claw were extracted based on a B-spline wavelet algorithm, and the results showed that the variable curvature of the beetle claw enhances its adhesion force and improves its strength. Adhesion models of the claw were established, and the mechanical properties of its biomaterials were measured using nanoindentation. Considering that the presence of water can affect the hardness and Young's modulus, both 'dry' and 'wet' samples were examined. For the dry samples, the hardness and Young's modulus were 0.197 ± 0.074 GPa and 1.105 ± 0.197 GPa, respectively, whereas the respective values for the wet samples were both lower at 0.071 ± 0.030 GPa and 0.693 ± 0.163 GPa. This study provides data that can inform the design of climbing robots.

Activity recognition using multiplex limited penetrable visibility graph.

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.

Mathematical Model and microCT-Based Kinematic Analysis of the Rostrum Mouthparts in Cyrtotrachelus buqueti Guer (Coleoptera: Curculionidae).

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.

[Analysis of prenatal phenotype and pathogenetic variant in a fetus with Papillorenal syndrome].

OBJECTIVE: To determine the carrier rate of deafness-related genetic variants among 53 873 newborns from Zhengzhou. METHODS: 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. RESULTS: 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. CONCLUSION: 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 IVS7-2A>G, 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.

Clinical research on the dexmedetomidine applied for patient-controlled sedation during the lower limbs operation under combined spinal-epidural anesthesia.

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 (P<0.05). Compared with HR in Group C, HR in Group PCS obviously slowered between T1 and T8 (P<0.05). Compared with the MAP at T0, MAP in Group PCS gradually increased between T1 and T3 and gradually reduced between T5 and T8 (P<0.05). MAP between T5 and T8 in Group PCS were significantly lower than those in Group C (P<0.05). 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.

[Effect of the treatment acceptance on the perinatal outcomes in women with subclinical hypothyroidism, positive thyroid gland peroxidase antibody in early pregnancy].

OBJECTIVE: 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. METHODS: 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. RESULTS: (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 (P < 0.05). While there was no statistically significant difference in the incidence of placental abruption, anemia in pregnant women, or fetal distress among the three groups (P > 0.05). (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 (P < 0.05). 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 (P > 0.05). (4) There were no statistically significant difference (P > 0.05) 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. CONCLUSIONS: (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.

Risk factors for early miscarriage among Chinese: a hospital-based case-control study.

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.

[Prevalence trend of neural tube defect in Zhengzhou city, 1996-2005].

OBJECTIVE: To describe the prevalence trend and epidemiological characteristics of neural tube defects (NTDs) in perinatal in Zhengzhou city from 1996 to 2005. METHODS: Data collected from hospital were used to depict the epidemiology of NTDs in Zhengzhou. All perinatal fetuses born in hospitals had an access within 7 days after delivery. The prevalence were calculated by perinatal'year, sex, birth area (urban versus rural) and maternal age. All monitored perinatal (162,074) accounted for 32.66% from totals (496,203). RESULTS: All 238 cases were found NTDs, and the overall prevalence rate was 14.68/10,000. The annual prevalence rate presented a decreasing trend during that period. The rates in rural and urban area, in male and female birth were 29.28/10,000 and 9.63/10,000, 11.42/10,000 and 17.74/10,000 respectively. There were significant differences among maternal-age-specific prevalence rates (chi2 = 22.952, P = 0.000). The rates of <20 years group(53.76/10,000) and >35 years group(21.74/10,000) were higher than others. CONCLUSION: The prevalence rates of NTDs in rural area is higher than that in urban, female's is higher than male's in Zhengzhou. The annual prevalence rates of NTDs presents a decreasing trend in the past ten years.