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An editorial is presented on the current research status of modeling of heterogeneous materials. In order to make up for the shortcomings of homogeneous materials and meet the needs of industry development, heterogeneous materials have been increasingly applied in aviation, automobile, bridge and other fields. Heterogeneous materials refer to advanced materials with non-uniform components.

Objective: To investigate the safety and efficacy of high-intensity focused ultrasound (HIFU) treatment for diffuse uterine leiomyomatosis (DUL). Methods: Eight patients with DUL were admitted to the Department of Gynecology of Shanghai First Maternity and Infant Hospital and underwent HIFU treatment. MRI was performed before and one day after HIFU treatment for the evaluation of lesion ablation. The uterine size was measured at 3- 8 months after HIFU ablation. The menstrual volume score and serum levels of hemoglobin and CA125 were measured pre-HIFU ablation and 12-36 months post-HIFU ablation. Results: After an average of 5.9 months of follow-up after HIFU treatment, an average uterine volume reduction of 67.6% was observed. Menstruation returned to normal in all patients, and their serum HGB and CA-125 levels also returned to normal after an average of 19.1 months of clinical follow-up. The quality of life of all patients improved significantly. Conclusion: HIFU treatment is safe and effective in the treatment of patients with DUL. [ABSTRACT FROM AUTHOR]

Objective: This randomized study aimed to compare the clinical efficacy between the novel dual tracer composed of indocyanine green (ICG) and blue dye (BD) and the conventional dual tracer composed of radioisotope and BD for sentinel lymph node (SLN) mapping in patients with breast cancer. Methods: This study enrolled 471 clinically lymph node-negative patients with primary breast cancer. All patients underwent mastectomy, and those undergoing sentinel lymph node biopsy (SLNB) were randomized to receive blue dye plus radioisotope (RB group) or BD plus ICG (IB group). The detection performances on SLN identification rate, positive SLN counts, detection sensitivity, and false-negative rate were compared between the two groups. Results: In the IB group, 97% (194/200) of the patients who underwent the ICG and BD dual tracer injection showed fluorescentpositive lymphatic vessels within 2-5 min. The identification rate of SLNs was comparable between the IB group (99.0%, 198/200) and the RB group (99.6%, 270/271) (P = 0.79). No significant differences were observed in the identification rate of metastatic SLNs (22.5% vs. 22.9%, P > 0.05, RB group vs. IB group, the same below), positive SLN counts (3.72 ± 2.28 vs. 3.91 ± 2.13, P > 0.05), positive metastatic SLN counts (0.38 ± 0.84 vs. 0.34 ± 0.78, P > 0.05), SLNB detection sensitivity (94.4% vs. 92.5%, P > 0.05), or false-negative rate (5.6% vs. 7.5%, P > 0.05) between the two groups. Conclusions: ICG can be used as a promising alternative tracer for radioisotope in SLN mapping, and when it is combined with BD in lymphangiography, it offers comparable detection sensitivity compared to the conventional lymphatic mapping strategies that are widely used in clinical practice. [ABSTRACT FROM AUTHOR]

Three-point bending fatigue test of 5083 and 5A06 aluminum alloy T-welded joints is carried out, and the fatigue life of the specimens with different influencing factors are obtained. Finite element model of the Twelded joint is established and the nodal force based structural stress is calculated. Neighborhood rough set theory is used for analysis of the factors which influence the fatigue life of the aluminum alloy welded joints. Key influencing factors are studied and the fatigue characteristic domains are determined. The master S-N curve characterized by the nodal force based structural stress range and cycles to failure on bi-logarithmic coordinate as well as S-N curves corresponding to the fatigue characteristic domain are fitted. A case study of fatigue life prediction of 5A06 aluminum alloy welded joint indicates the effectiveness of the fatigue life prediction method based on the fatigue characteristic domain. [ABSTRACT FROM AUTHOR]

The annual distribution and variations in dust weather occurrence (DWO) have been analyzed using monthlyDWO data from 26 stations over the Tarim Basin during the period of 1961 to 2010. The results show that the DWO presents a significant decreasing trend for different parts of the Tarim Basin in recent decades. The monthly DWO has two peaks in the east and west. In the first half of the year, the peak is in April, but in the second half of the year, the peak is in September. According to the concentration period and concentration degree (CD) of DWO, we can find that the maximum DWO occurs in April in the eastern, western, and northern parts of the basin, but it occurs in May in the southern part. The dust weather season is shorter for the northern and eastern parts of the basin than those of the remaining parts. On average, the dust weather season initiates in April in the northeast and in May for the rest of the region. As an indicator for the length of dust weather season, the CD is significantly related to DWO, with a correlation coefficient of -0.51, revealing an interesting feature of regional climate change with declining DWO and declining dust weather season over the Tarim Basin. The correlation analysis exhibits that all the Arctic Oscillation, Antarctic Oscillation, and North Atlantic Oscillation have a negative relation with the DWO but a positive relation with the length of dust weather season. [ABSTRACT FROM AUTHOR]

The mechanical properties of asphalt mixture always exhibit large degrees of variability due to asphalt's random internal structure. A stochastic constitutive model is proposed to describe the random mechanical response of an uniaxially compressed asphalt mixture. In this model, the simplified Schapery's nonlinear viscoelastic model and the modified Swchartz's viscoplastic model are combined to estimate the material average deformation, and a random parameter with lognormal probability distribution is introduced to reflect the specimen dispersion. Based on statistical methods, the model is calibrated by the multiple-stress repeated creep-recovery test and the 1-h creep test, and then validated by the irregular loading test and the uniform repeated creep-recovery test. It is shown that the model can predict not only the average mechanical behavior but also the scattering range of the material responses at a certain probability. [ABSTRACT FROM AUTHOR]

Roller bearings are the most widely used and easily damaged mechanical parts in rotating machinery. Their running state directly affects rotating machinery performance. Empirical mode decomposition (EMD) easily occurs illusive component and mode mixing problem. From the view of feature extraction, a new feature extraction method based on integrating ensemble empirical mode decomposition (EEMD), the correlation coefficient method, and Hilbert transform is proposed to extract fault features and identify fault states for motor bearings in this paper. In the proposed feature extraction method, the EEMD is used to decompose the vibration signal into a series of intrinsic mode functions (IMFs) with different frequency components. Then the correlation coefficient method is used to select the IMF components with the largest correlation coefficient, which are carried out with the Hilbert transform. The obtained corresponding envelope spectra are analyzed to extract the fault feature frequency and identify the fault state by comparing with the theoretical value. Finally, the fault signal transmission performance of vibration signals of the bearing inner ring and outer ring at the drive end and fan end are deeply studied. The experimental results show that the proposed feature extraction method can effectively eliminate the influence of the mode mixing and extract the fault feature frequency, and the energy of the vibration signal in the bearing outer ring at the fan end is lost during the transmission of the vibration signal. It is an effective method to extract the fault feature of the bearing from the noise with interference. [ABSTRACT FROM AUTHOR]

The scatter degree of the fatigue samples is reduced when the nodal force based structural method is used for steel welded joints, while it is still high for aluminum alloy welded joints. Statistical method and rough set theory is used to fatigue analysis so that fatigue characteristic domains are determined and S-N curves are fitted. Experiment results show that fatigue life of the aluminum alloy welded joints is under the influence of some key factors and the fatigue data with the same characteristics distribute in a relatively independent area. Accordingly, a novel S-N curve modeling method of aluminum alloy welded joints based on the fatigue characteristics domain is proposed. In the proposed method, the nodal force based structural stress method is used for stress calculation and neighborhood rough set theory is used for character extraction to obtain the key factors. Then fatigue characteristics domains are divided and S-N curves are fitted on each fatigue characteristics domain instead of on the whole domain so that a set of S-N curves are obtained. Statistical results show that selection of the S-N curve for the aluminum alloy welded joints according to different fatigue characteristic domain is more accurate. [ABSTRACT FROM AUTHOR]

Ultrasonic bonding has an increasing application in the micro assembly of polymeric micro-electro mechanical systems (MEMS) with high requirements for fusion precision. In the ultrasonic bonding process, the propagation of ultrasonic vibration in polymer components is related to the interfacial fusion, which can be used as a monitoring parameter to control ultrasonic energy. To study the vibration propagation in viscoelastic polymer components, finite element analysis on the bonding of poly methyl methacrylate (PMMA) micro connector to substrate for microfluidic system is carried out. Curves of propagated vibration amplitude corresponding to interfacial temperatures are obtained. The ultrasonic vibration propagated in PMMA components are measured through experiments. The theoretical and experimental results are contrasted to analyze the change mechanism of vibration propagation related to temperature. Based on the ultrasonic bonding process controlled by the feedback of vibration propagation, interfacial fusions at different vibration propagation states are obtained through experiments. Interfacial fusion behavior is contrasted to the propagated vibration amplitude in theoretical and experimental studies. The relation between vibration propagation and fusion degree is established with the proper parameter range for the obtained high quality bonding. [ABSTRACT FROM AUTHOR]

An evaluation model of aluminum alloy welded joint low-cycle fatigue data based on information entropy is proposed. Through calculating and analyzing the information entropy of decision attributes, quantitative contribution of stress concentration, plate thickness, and loading mode to the fatigue destruction are researched. Results reveal that the total information entropy of the fatigue data based on nominal stress, structural stress and equivalent structural stress are, respectively, 0.9702, 0.8881, and 0.8294. There is consistency between the reducing trend of the weight-based information entropy and the smaller and smaller standard deviation of the S-N curves. In the structural stress based S-N curve, total stress concentration factor is crucial for the distribution of the fatigue data and the weight based information entropy of membrane stress concentration factor is 0.6754, which illustrates that stress concentration is a key issue of welded structure to which ought to be attached great importance. Subsequently, in the equivalent structural stress-based S-N curve, the weight based information entropy of stress ratio is 0.5759, which plays an important role in the distribution of fatigue data. With the importance level of the attributes on the S-N curves investigated, the correction of R in the equivalent structural stress based master S-N curve method should be carried out to make the welding fatigue prediction much more accurate. [ABSTRACT FROM AUTHOR]

Feature extraction is one of the most important, pivotal, and difficult problems in mechanical fault diagnosis, which directly relates to the accuracy of fault diagnosis and the reliability of early fault prediction. Therefore, a new fault feature extraction method, called the EDOMFE method based on integrating ensemble empirical mode decomposition (EEMD), mode selection, and multi-scale fuzzy entropy is proposed to accurately diagnose fault in this paper. The EEMD method is used to decompose the vibration signal into a series of intrinsic mode functions (IMFs) with a different physical significance. The correlation coefficient analysis method is used to calculate and determine three improved IMFs, which are close to the original signal. The multi-scale fuzzy entropy with the ability of effective distinguishing the complexity of different signals is used to calculate the entropy values of the selected three IMFs in order to form a feature vector with the complexity measure, which is regarded as the inputs of the support vector machine (SVM) model for training and constructing a SVM classifier (EOMSMFD based on EDOMFE and SVM) for fulfilling fault pattern recognition. Finally, the effectiveness of the proposed method is validated by real bearing vibration signals of the motor with different loads and fault severities. The experiment results show that the proposed EDOMFE method can effectively extract fault features from the vibration signal and that the proposed EOMSMFD method can accurately diagnose the fault types and fault severities for the inner race fault, the outer race fault, and rolling element fault of the motor bearing. Therefore, the proposed method provides a new fault diagnosis technology for rotating machinery. [ABSTRACT FROM AUTHOR]

MicroRNAs (miRs) have important roles in the parthenogenesis of malignancies. While it has been suggested that deregulation of miR-101 is involved in bladder cancer, the underlying mechanisms have remained largely elusive. The present study aimed to investigate the roles of miR-101 in the regulation of bladder cancer cell proliferation and invasion. Reverse-transcription quantitative polymerase chain reaction analysis revealed that the expression of miR-101 was significantly reduced in the HT-1376, BIU87, T24 and 5637 several human bladder cancer cell lines compared to that in the SV-HUC-1 normal bladder epithelial cell line. Furthermore, a Targetscan search and a luciferase assay were used to identify c-FOS as a novel target of miR-101, and western blot analysis indicated that the protein expression of c-FOS was shown to be negatively regulated by miR-101 in bladder cancer T24 cells; however, c-FOS mRNA expression was not affected. In addition, plasmid-mediated overexpression of miR-101 and small hairpin RNA-mediated inhibition of c-FOS significantly inhibited the proliferation and invasive capacity of T24 cells, as indicated by an MTT and a Transwell assay, respectively. However, plasmid-mediated overexpression of c-FOS reversed the inhibitory effects of miR-101 overexpression on T24-cell proliferation and invasion. In conclusion, the present study demonstrated that miR-101 inhibits the proliferation and invasion of bladder cancer cells, at least partly via targeting c-FOS, suggesting that miR-101/c-FOS signaling may represent a potential therapeutic target for bladder cancer. [ABSTRACT FROM AUTHOR]

Background: Sentinel lymph node (SLN) mapping is the standard method for axillary lymph node staging in patients with breast cancer. Blue dye and radioisotopes are commonly used agents to localize SLNs, but both have several disadvantages. The purpose of this study was to evaluate magnetic resonance lymphography with a gadolinium-based contrast agent (Gd-MRL) in sentinel lymph node identification and metastasis detection in patients with breast cancer. Methods: Sixty patients (mean age: 46.2 ± 8.8 years) with stage T1- 2 breast cancer and clinically negative axillary lymph nodes participated in this study. After 0.9 ml of contrast material and 0.1 ml of mepivacaine hydrochloride 1% were mixed and injected intradermally into the upper-outer periareolar areas, axillary lymph flow was tracked and sentinel lymph nodes were identified by Gd-MRL. After SLN biopsy and/or surgery, the efficacy of SLN identification and metastasis detection of Gd-MRL were examined. Results: Ninety-six lymph nodes were identified by Gd-MRL as SLNs (M-SLN), and 135 lymph nodes were detected by blue dye-guided methods as SLNs (D-SLN). There was a strong correlation (P < 0.001) between the SLN numbers found by these two methods. Using blue dye-guided methods as the gold standard, the sensitivity of Gd-MRL was 95.65% and the false-negative rate was 4.3% for axillary lymphatic metastasis detection. With heterogeneous enhancement and enhancement defect as the diagnostic criteria, Gd-MRL gave a sensitivity of 89.29% and specificity of 89.66% in discriminating malignant from benign SLNs. Conclusion: Gd-MRL offers a new method for SLN identification and metastasis detection in patients with breast cancer. [ABSTRACT FROM AUTHOR]

In welding techniques, failure is a key problem that is related to the stability and safety of the welded structure. In the commonly used welding fatigue analysis methods, the Master S-N curve method based on Battelle structural stress solves the problem of inconsistencies in stress calculation and S-N curve selection better than the nominal stress method and hot spot stress method. In this paper, rough set theory was employed to study the S-N distribution based on the Battelle equivalent structural stress. Firstly, rough set analyses of the S-N distribution based on the nominal stress, structure stress and Battelle equivalent structure stress were carried out. Then the S-N distributions based on the three stresses were studied. The results indicated that structural stress rearranges the S-N point making it much more concentrated in the region near the mean S-N curve and that equivalent structural stress places the S-N point more uniformly on both sides of the curve. Subsequently, the corrections from the plate thickness and stress ratio in the Master S-N curve method were studied. It was concluded that with two steps of corrections the decision-making degrees of welding factors are weakened and harmonized in the Battelle equivalent structural stress. This made the S-N distribution much more concentrated and uniform, which allows more accurate welding fatigue prediction by the Master S-N curve. [ABSTRACT FROM AUTHOR]

The aim of the present study was to detect the differences in the protein expression between Uyghur females with or without endometriosis (EM). The two dimensional (2D) gel images of proteins extracted from the serum of Uyghur and Han females with EM and the controls were analyzed using Phoretix 2D software, and the differentially expressed proteins were identified primarily by database query. Having compared the reproducible 2D gel images of proteins from the serum of Uihgur and Han females with and without EM, 13 differentially expressed proteins were obtained from Uyghur females and eight differentially expressed proteins were obtained from Han females. The present study demonstrated ethnic differences in gene and protein expression between Uyghur and Han females with EM. [ABSTRACT FROM AUTHOR]

Background: Breast conservation therapy (BCS) after neoadjuvant chemotherapy (NCT) can improve patients' quality of life. Currently used intraoperative examination for negative margins may not be sufficient to detect microresidual foci, which are a risk factor for local recurrence. This study was conducted to investigate the shrinking pattern of breast cancer and residual tumors as a risk factor for BCS after NCT. Methods: Ninety women with stage II or III invasive ductal carcinoma who achieved partial response after NCT with paclitaxel and epirubicin were enrolled. All patients had undergone modified radical mastectomy. One-half of the surgical specimens were subjected to subserial sectioning. Pathological changes of tumor bed and pericancerous tissues were examined with an optical microscope. The levels of estrogen receptors, progesterone receptors and HER2 were analyzed by immnohistochemical staining. Results: The residual tumors were classified into three types according to their microscopic morphology: solitary lesion, multifocal and patchlike lesions, and main residual tumor with satellite lesions. Type I residual tumors were found in 55 patients (61%), type II in 30 patients (33%) and type III in 5 patients (6%). Types II and III were often associated with larger primary tumors. The types of residual tumors were not correlated with the status of hormone receptors or HER2. Conclusion: Three types of residual tumors were observed after NCT. The solitary residual tumor is most common, but main residual tumors with satellite lesions are most likely to cause local recurrence after BCS. Subserial sectioning would improve the identification of microfoci and patient survival after BCS. [ABSTRACT FROM AUTHOR]

Poland's syndrome is a rare congenital development malformation characterized by unilateral chest wall hypoplasia and ipsilateral hand abnormalities. It is also known to be associated with some malignant diseases. We herein report a case of Poland's syndrome associated with invasive ductal carcinoma of breast, and review the literatures to investigate the clinical characteristics of breast cancer with Poland's syndrome. [ABSTRACT FROM AUTHOR]

Asphalt sand is described as a viscoelastoplastic materials. To involve elastic, viscoelastic, and viscoplastic strain components, a modified Schapery’s model is proposed through adding a viscoplastic term to the Schapery’s model with elastic and viscoelastic terms, and a strain-hardening model is used to describe viscoplastic behavior. A set of uniaxial compression tests, repeated and simple creep-recovery tests in different stress levels are performed to determine the stress-dependent parameters in the model. Finally, the model is validated by comparison with the results from the uniaxial creep experiments. Better agreement than the Schapery’s model indicates that the modified model is practicable to describe the mechanical behavior of asphalt sand in uniaxial compression. [ABSTRACT FROM AUTHOR]

The article relates a study on the developmental status of human resource staffing and services functions of community health services (CHS) in China. It was found in the study that large number of physicians and nurses employed in CHS centers have low-level medical training. Also, more than 50% of CHS organization have developed on-the-job training programs, causing cost trends for staff training to increase. The authors also offer recommendations for improving the CHS function.

ALLow Improved Access in the Network via Cooperation and Energy Savings (ALLIANCES) is a recently proposed cooperative random access protocol for wireless networks that capitalizes on the broadcast nature of the wireless channel. When a collision occurs, a set of nodes forms an alliance and retransmits the collision signal that they heard. The initial collision and retransmissions provide the diversity that is exploited to resolve collisions and, thus, attain high throughput. In this paper, we modify the original model to include node location information. We derive pair-wise error probability (PEP) under a Rayleigh flat-fading channel and a power-law attenuation environment. Based on the PEP analysis, we propose a location relay selection scheme that achieves significant bit-error-rate gains as compared to the random relay selection scheme in the original ALLIANCES. [ABSTRACT FROM AUTHOR]

Background: The Medication Adherence Rating Scale (MARS) is a rapid, non-intrusive way of measuring adherence to medication in order to improve management of patients with schizophrenia. The current study evaluated the reliability of the Chinese (Mandarin) version of the MARS and explored clinical and demographic correlates to medication adherence in a large sample of patients with recurrent schizophrenia in China. Methods: 1198 patients with recurrent schizophrenia were recruited from 37 different hospitals in 17 provinces/municipalities of China and evaluated with the Medication Adherence Rating Scale (MARS), Clinical Global Impression-Severity of illness (CGI-S) and Sheehan Disability Scale- Chinese version (SDS-C). Socio-demographic data included gender, age, marital status, education level, employment status and living with others or alone. Clinical data included duration of illness, number of relapses, and medication use, as well as current stage of disease evaluated by SCID. Pearson correlations were used to examine associations between MARS, socio-demographic, and clinical characteristics. Independent sample T-tests were used to compare MARS score between different socio-demographic and clinical characteristics. Finally, a cut-off score of 6 on the MARS (ranged from 1 to 10) was used to divide the sample into two groups (i.e. MARS score≥ 6 identified good adherence and MARS score< 6 indicated poor adherence). Bivariate logistic regression models with the two groups (MARS score<6 and MARS score≥6) as the dependent variable was used to identify influencing factors of medication adherence. Data processing and analyses were conducted on SPSS 22.0 and Mplus 7.4. Results: The MARS showed good internal consistency and psychometric properties. MARS outcomes varied by demographic and clinical characteristics; only 28.5% recurrent schizophrenia patients met the criteria of good adherence to antipsychotic medication. Findings indicated older age (OR=1.04, 95%CI=1.02–1.06), unsteady income (OR=1.79, 95%CI=1.29– 2.49), acute period (OR=4.23, 95%CI=3.21–5.59) and a higher CGI-S score (OR=1.44, 95%CI=1.03–2.01) had significantly predictive effects on poor medication adherence. MARS demonstrated good reliability in our sample (Cronbach’s α =0.83; Spearman-Brown = 0.72). Discussion: This study of the MARS is unique for a few reasons. First, comparative reports on MARS use in mainland China have not been published internationally; similar tests on reliability and correlation have only been reported in Hong Kong and Taiwan (Hui et al., 2006; Kao and Liu, 2010). Second, in considering demographic and clinical correlates of medication adherence in patients with recurrent schizophrenia, our MARS study broadly represents China with 17 of 27 provinces/municipalities reporting data from multiple geographic regions, with the participation of hundreds of psychiatrists across China. Only 28.5% recurrent schizophrenia patients met the criteria of good adherence to antipsychotic medication in this study. Low levels of good medication adherence in schizophrenia patients are found across Asia, with 27% in Korea meeting the criteria of good adherence (Kim et al., 2006) and 26% in Hong Kong (Hui et al., 2006). Overall MARS total score in our study (3.68 ±2.90) is comparably lower to that of developed countries, as MARS total score had a mean of 6.0 to 7.7 in a UK sample (Fialko et al., 2008; Jaeger et al., 2012), and 5.5 for schizophrenia patients in France (Zemmour et al., 2016). Medication adherence of patients affected by recurrent schizophrenia in China was found to be relatively low. Risk factors for non-adherence to medication in recurrent schizophrenia patients include older age, unsteady income, acute period and severity of illness. [ABSTRACT FROM AUTHOR]

The deformation behavior and grain boundary (GB) response of nanocrystalline Ni under cyclic shear loading are investigated by molecular dynamics simulations. The GB migration hysteresis phenomenon, in which the GB migration displacement lags behind the change in nominal shear strain, is observed in the symmetric tilt GBs for the first time. The elementary structure transformation occurring at the two end segments of the observed GB during GB migration produces a disordered and irreversible state, while the transformation in the middle segment is reversible. Both dislocation retraction and nucleation occur during unloading. Relatively large cyclic strain amplitudes lead to disordered GB segments of greater length, such that the residual GB migration displacement increases with increasing cyclic amplitude. GB migration hysteresis vanishes after the GB becomes immobile owing to a cyclic shear induced transition to a disordered state along its entire length. [ABSTRACT FROM AUTHOR]