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Bow wave breaking is a common phenomenon during ship navigation, especially at a high speed, involving complex physical mechanism such as interface mixing, air entrainment, and jet splashing. This study uses the delayed detached eddy simulation (DDES) turbulence model on the OpenFOAM platform to simulate flow around a KRISO Container Ship (KCS) model for a Froude number of 0.35, examining trim angles of 0°, 0.5°, 1°. This paper analyzes the statistical and power spectral density (PSD) characteristics of bow wave heights. The analysis shows root mean square (rms) and mean difference between top and bottom views indicate wave breaking. As the trim angle increases, peaks of rms in the bottom view become much higher than that in the top view, reaching 38% at 1°. PSD analysis reveals that resistance and wave height periods differ by no more than 5%, with small-scale structures like jetting and splashing causing non-dominant periodic and high-frequency wave height variations.

By means of their specific interactions with different metal ions, naturally occurring proteins control structures and functions of many biological processes and functions in organisms. In view of natural metallopeptides, scientists have proposed artificial peptides which coordinate with metal ions through their functional groups either for introducing a special reactivity or for constructing various sensors. However, the design of new peptide ligands requires a deep understanding of the structures, assembly properties, and dynamic behaviors of such peptides. This review briefly describes detection strategies of metal ions viacoordination to the binding sites in peptides. The principles and functions of sensing systems are described as well. We also highlight some examples of a metal-induced peptide self-assembly with relevance to biotechnology applications.

In order to increase the utilization rate of vanadium–titanium magnetite in blast furnace smelting, the viscosity and potassium removal capacity of CaO–SiO2–Al2O3–MgO–BaO–TiO2slag (CaO/SiO2= 1.05, 1–5 wt.% BaO, 2–20 wt.% TiO2) were studied for slag optimization using the cylinder method and slag–metal equilibrium technique, respectively. Also, the structural properties of the slag were characterized by Fourier transform infrared spectroscopy. The concept of “a ring structure of Ti–O–Si” was proposed to express the change in the viscosity of the blast furnace slag. The results showed that the viscosity of slag increased with the increase in BaO content while the potassium removal capacity decreased. Furthermore, an increase in TiO2content from 2 to 20 wt.% resulted in a decrease in viscosity and an increase in potassium removal capacity. The Fourier transform infrared spectroscopy results showed that the charge compensation of Ba2+can form complex aluminosilicate structure and increase the viscosity of slag. Meanwhile, with the increase in TiO2content, Ti4+ions replace Si4+in the silicon-oxygen tetrahedral structure, thereby reducing the degree of polymerization of the silicate network and decreasing the viscosity.

The self-reported quality of life (QoL) should be carefully listened to in progressive supranuclear palsy (PSP) from the patient-centered perspective. However, there was still a lack of short QoL measurement tool in atypical parkinsonism. We aimed to test whether the short Parkinson’s Disease Questionnaire-8 (PDQ-8) was effective in assessing QoL in PSP, comparing with Progressive Supranuclear Palsy Quality of Life Scale (PSP-QoL) and Parkinson’s Disease Questionnaire-39 (PDQ-39). 132 patients with clinical diagnosed PSP, including PSP-Richardson syndrome (RS) subtype (n= 71) and PSP-non-RS subtype (n= 61) were recruited for clinical evaluation including QoL assessment. The detailed QoL profiles and possibility of using PDQ-8 were systemically analyzed. The determinants to the QoL were then calculated by multivariate linear regression analysis. The PSP-QoL total score summary index (SI) was 22.8 (10.1, 41.1), while the PDQ-8 and PDQ-39 total SI score were 28.1 (12.5, 46.9) and 29.5 (15.4, 49.4). Mobility, activities of daily life, cognition and communication were the main affected QoL subdomains (median SI: 40.0, 31.3, 25.0 and 25.0 respectively). PSP-RS subtype showed more severe damage physically (p<0.001) and mentally (p= 0.002) compared to other subtypes. More importantly, the strong relevance of PDQ-8 and recommended PSP QoL tools were confirmed (p<0.001). In addition, disease severity, depression and daytime sleepiness were proved to be critical determinants for QoL in PSP. PDQ-8 could be an easy, reliable, and valid tool to evaluate QoL in patients with PSP. Besides motor symptoms, more attention should be paid to non-motor impairment such as depression in PSP.

Objective: To compare survival outcomes between primary radical surgery and primary radiation in early cervical cancer. Methods: Patient information was extracted from the Surveillance, Epidemiology, and Results database. Patients diagnosed with early cervical cancer of stage T1a, T1b, and T2a (American Joint Committee on Cancer, 7th edition) from 1998 to 2015 were included in this study after propensity score matching. Overall survival (OS) was analyzed using the Kaplan-Meier method. Results: Among the 4964 patients included in the study, 1080 patients were identified as having positive lymph nodes (N1), and 3884 patients were identified as having negative lymph nodes (N0). Patients with primary surgery had significantly longer 5-year OS than those with primary radiotherapy in both the N1 group (P&lt;0.001) and N0 group (P&lt;0.001). In the subgroup analysis, similar results were found in patients with positive lymph nodes of stage T1a (100.0% vs.61.1%), T1b (84.1% vs.64.3%), and T2a (74.4% vs.63.8%). In patients with T1b1 and T2a1, primary surgery resulted in longer OS than primary radiation, but not in patients with T1b2 and T2a2. In multivariate analysis, the primary treatment was identified as an independent prognostic factor in both N1 and N0 patients (HRN1=2.522, 95% CI=1.919–3.054, PN1&lt;0.001; HRN0=1.895, 95% CI=1.689–2.126, PN0&lt;0.001). Conclusion: In early cervical cancer stage T1a, T1b1, and T2a1, primary surgery may result in longer OS than primary radiation for patients with and without lymph node metastasis.

A biological nanopore is one of the predominant single-molecule approaches as a result of its controllable single-biomolecule interface, which could reflect the “intrinsic” information on an individual molecule in a label-free way. Because the current blockage is normally treated as the most important parameter for nanopore identification of every single molecule, the fluctuation of current blockage for certain types of molecules, defined as full width at half maximum (fwhm) of current blockage, actually owns a dominant influence on nanopore resolution. Therefore, controlling the fwhm of current blockage of molecules is critical for the sensing capability of the nanopore. Here, taking an aerolysin nanopore as a model, by precisely controlling the functional group in this single-biomolecule interface, we could narrow the fwhm of nanopore current blockage for DNA identification and prolong the duration inside the nanopore. Moreover, a substantial correlation between fwhm of current blockage and duration is established, showing a non-monotonic variation. Besides, the mechanism is also clarified with studying the detailed current blockage events. This proposed correlation is further demonstrated to be applied uniformly across different mutant aerolysins for a certain DNA. This study proposes a new strategy for regulating molecular sensing from the duration of the analyte, which could guide the resolution of heterogeneity analysis using nanopores.

The nectar spur is an important feature of pollination and ecological adaptation in flowering plants, and it is a key innovation to promote species diversity in certain plant lineages. The development mechanism of spurs varies among different plant taxa. As one of the largest angiosperm genera, we have little understanding of the mechanism of spur development in Impatiens. Here, we investigated the initiation and growth process of spurs of Impatiens uliginosabased on histology and hormone levels, and the roles of AUXIN BINDING PROTEIN (ABP) and extensin (EXT) in spur development were explored. Our results indicate that the spur development of I. uliginosais composed of cell division and anisotropic cell elongation. Imbalances in spur proximal-distal cell division lead to the formation of curved structures. Endogenous hormones, such as auxin and cytokinins, were enriched at different developmental stages of spurs. IuABPknockdown led to an increase in spur curves and distortion of morphology. IuEXTknockdown resulted in reduced spur length and loss of curve and inner epidermal papillae structures. This study provides new insights into the mechanism of spur development in core eudicots.

In the process of ceramic stereolithography, the polymerization process of acrylate is exothermic, resulting in changes to temperature of the slurry, which may affect the quality of green parts. In this work, the heat source input in simulation is based on the in-situ measurement of conversion rate and calculated polymerization exotherm. The simulation results showed that the different structures underwent a 1~3°C maximum temperature rise. A thermal infrared detector was used to capture the in-situ temperature changes in entire exposure surface for several structures during the photopolymerization process. The experimental data validated the simulation results and showed that the temperature change and distribution area in the process were related to the exposure structure. The discontinuous structure and the increase of structural boundary length could accelerate the thermal diffusion, thus reducing the heat concentration in the center. Polymerization rate rose marginally with the incident light intensity until at the intensity of 20 milliwatts. Besides, intensity had little effect on the temperature gradient from the center to the boundary of the exposure area. It is inferred that the additional temperature rise after the peak temperature is an indicator of the occurring of secondary photopolymerization during multilayer exposure. And for the same input energy, reducing the exposure intensity and increasing the exposure time to some extent may help improve the degree of secondary photopolymerization. This work provided valuable guidance for the study of the photopolymerization process and structural design of ceramic stereolithography.

•We performed a meta-analysis to evaluate the status of Treg cells in pathogenesis of MS patients and performed subgroup analysis based on different definition methods of Tregs for the first time.•The result of our study was different from previous study. Under random effect model of meta-analysis, the data showed that the results of Tregs were different according to the definition methods; and Tregs defined by “CD4+CD25+FOXP3+” were decreased in MS. That result demonstrated that FOXP3 may be a vital definition of Tregs, and Tregs defined by stricter definition methods may be involved in the pathogenic mechanisms of MS.•As “CD4+CD25+FOXP3+” Tregs is associated with pathogenesis of MS, we hypothesis that Tregs may become a novel diagnostic method and a promising therapeutic target in MS patients.

The aim of the present study was to investigate the effect of lipoxin A4 (LXA4) pretreatment on cognitive function of aged rats after global cerebral ischemia reperfusion, and to explore its possible mechanism. Thirty-six aged male Sprague-Dawley rats were randomly divided into three groups (n=2 each): sham-operation group (S group), global cerebral ischemia reperfusion group (I/R group) and LXA4-pretreatment group (L group). The rat model of global cerebral ischemia reperfüsion was established by occlusion of the bilateral common carotid artery with hypotension. The cognitive function of rats was determined by a step-down type passive avoidance test and Morris Water Maze test on the third day after reperfUsion. Rats were sacrificed after Water Maze test and the pathological changes of hippocampal CAI region were observed and the related inflammatory mediators were determined. As compared with S group, the escape latency in I/R group was prolonged from the first day to the fifth day, while that in L group was prolonged from the first day to the third day. The retention time in I/R group and L group in the first quadrant was shortened. The reaction time, frequency of reaction mistake and frequency of escape mistake in I/R group increased, and the latent period shortened. The frequency of escape mistake in L group increased, and the damage in the hippocampal CAI region of I/R group and L group was obvious. The levels of S-100β, TNP-α, IL-lβ, IL-10 and NF-κB in I/R group and L group increased. As compared with I/R group, the escape latency in L group was shortened from the first day to the fifth day, and the retention time in the first quadrant prolonged. The reaction time, frequency of reaction mistake and frequency of escape mistake in L group decreased, and the latent period prolonged. The damage in the hippocampal CAI region of L group was alleviated as well. The levels of S-100β, TNP-α, IL-lβ and NF-κB in L group decreased, and those of IL-10 increased. It can be concluded that LXA4 pretreatment can improve the cognitive function in aged rats after global cerebral ischemia reperfusion probably by inhibiting the inflammatory reaction.

ABSTRACTWith high speed and broad view, airborne radar has a great advantage in moving vehicle tracing, recognition and strike. The high speed also causes complexity in feature extraction of radar echo. In view of this situation, point scatterer models are presented to depicting micro-Doppler effect of vehicle targets, and micro-Doppler signatures are analyzed in time and frequency domain. Also, eigenvalue spectrum is extracted as a feature distinguishing between wheeled vehicles and tracked vehicles, and classification experiments are performed using support vector machine. Experimental results validate the models, and show that the feature extraction method is robust and the classifier is effective.

Multiple reports have described the proportion of Th17 cells in peripheral blood and serum levels of Th17-related cytokines in patients with multiple sclerosis (MS). To clarify the status of Th17 cells and Th17-related cytokines in MS patients, we did a meta-analysis of the results published previously to assess the levels of peripheral Th17 cells and serum Th17-related cytokines in patients with MS.

A new dioscin-bonded silica gel stationary phase with natural active ingredient for high performance liquid chromatography was prepared by one-pot reaction method, using 1,6-diisocyanate as the spacer arm. The structure of new stationary phase was characterized by solid-state NMR techniques, infrared spectroscopy, elemental analysis, thermogravimetric analysis and scanning electron microscope. These results show that the dioscin has been bonded to the silicia gel. The resulting stationary phase containes 127.6 μmol/g dioscin ligand. The chromatographic performance of this new stationary phase was evaluated by different kinds of solute probes. The results illustrate that the new stationary phase has a typical reversed phase chromatographic property, meanwhile it could present various interactions with solutes. The HPLC fingerprint of PNS(Panax Notoginseng saponins) API(active pharmaceutical ingredient) on the dioscin-bonded silica gel stationary phase was established. The mobile phase was consisted of gradient acetonitrile and water. The detection wavelength was 203 nm, the column temperature was maintained at 35 degrees Celsius, the flow rate was 0.8ml/min and the injection volumn was 15 μL. The contents of the 5 co-possessing components were determined simultaneously. A new material for HPLC was made by natural product. The using of dioscin-bonded silica gel stationary phase provides a new idea in natural products research.

The local equilibrium in the kinetic process of dissolution is addressed. The measured dissolution kinetic data of Ag on Cu(111) surface are well fitted by the modified Darken model. Using the obtained fitting parameters, the discontinuous transition of Ag surface concentration against the bulk concentration of the neighboring layers deduced from the local equilibrium model is quantitatively interpreted.

The discontinuous transition of surface concentration due to the change of bulk concentration in isosteric/isothermal surface segregation has been discussed quantitatively according to the modified Darken model. The criteria for observing the discontinuous transition in surface segregation has been derived on the basis of the Bragg-William expression.

The character of COD release in the sediment of Tang He Reservoir was studied under the condition of different concentrations, temperatures, pHs, disturbances, and dissolved oxygen through indoor simulation experiment. It was concluded that sediment could adsorb more organic pollutants when the river was at a higher concentration; whether the temperature was raised or lowered, the COD emission all increased, so the maintenance of temperature could inhibit the release of COD in water; the water stable at the pH of 8; disturbance significantly increased the released quantity of COD; low dissolved oxygen could promote release of COD. The study can provide scientific basis for comprehensive treatment of Tang He Reservoir.

In this paper Yuan River was taken as an example of the southern river, and Taizi River was an example of the northern river. Based on the contents of ammonia nitrogen, total nitrogen, total phosphorus and COD in the sediments, the distribution of pollutants in the sediments along the Yuan River and Taizi River were analyzed; When the pollutant contents of individual sections were particularly higher, the pollution sources were studied; Through the contrast of pollutants contents in sediments between Yuan River and Taizi River, the contents of Taizi River were higher 2-5 times than Yuan River. Then the causes were summarized from temperature,hydrological condition, discharge of industrial and domestic wastewater and sand contents.

CZTS thin films are fabricated by sulfurizing co-sputtered metallic precursor CuZnSn layers under H2S atmosphere. The precursor layers are Cu-poor, Zn-rich deposited and the fabricated films are about 2 µm in thickness. A closed-tube process is preferred with regard to its producing large closely pack grains with smooth surface. XRD and Raman confirm the CZTS structure and the impurities on the surface are removed after suitable chemistry treatments. The band gap of the CZTS is determined to be 1.48 eV by extrapolation. Some more CZTS films are product with slightly changed parameters, sulfurization time, temperature and concentration of H2S, respectively. It is supposed that beside sulfurization time, the temperature could be more significant than concentration of H2S in the closed system.

BACKGROUND: A large number of sudden cardiac arrests occur annually, but the worldwide survival rate is less than 1%. Early initiation of bystander Cardiopulmonary resuscitation (CPR) would improve the survival rate of out-of-hospital sudden cardiac arrests. Students play an important role as bystanders on and off campus both now and in the future. So we wanted to investigate the awareness and attitudes towards CPR of Chinese students, in order to improve the dissemination of bystander CPR in China. METHODS: The survey was conducted by questionnaire in November 2007. We had chosen 3500 students from the city of Wuhan in China randomly according to the stratified cluster sampling technique. RESULTS: There were 3248 questionnaires answered, and 2763 questionnaires were considered valid. Few respondents reported that they had heard (28%) and studied (27%) of CPR, and only 3% of the respondents had attended a CPR course. The two major sources of information about CPR for Chinese students were television and books. Most respondents expressed a desire to learn CPR (77%), and were willing to disseminate CPR (73%). CONCLUSION: Dissemination of CPR among Chinese students has not been executed satisfactorily. The finding highlights the importance of CPR dissemination and efforts should be made to provide more convenient, effective and attractive ways for the Chinese public, especially students, to learn CPR.

C−C linked fused triazolo-triazine with vicinal C−NH2/C−NO2groups (4) and that with C−NH2/C−CN groups (2) were synthesized through the diazotization and cyclization of 3,3′-diamino-5,5′-bis(1H-1,2,4-triazole) with nitroacetonitrile and malononitrile, respectively. The [3 + 2] cycloaddition of the cyano group in compound 2using sodium azide resulted in bis-triazolo-triazine with vicinal C−NH2/C−tetrazole group (3). Compounds 2–4were characterized through infrared spectroscopy, NMR spectroscopy, and elemental analysis. Moreover, the structures of compounds 2and 4were confirmed through single-crystal X-ray diffraction. Remarkably, compound 4had a density of 1.84 g·cm−3and very high thermal decomposition temperature (349 °C, onset) and was insensitive to impact and friction (IS > 40 J, FS > 360 N). The detonation velocity and pressure of compound 4were calculated to be 8.125 km s−1and 26.1 GPa, respectively using EXPLO5. These results indicate that compound 4is an excellent candidate for heat-resistant explosives.

Objectives. To review the evidence of acupuncture for acute and preventive treatment of migraine for further awareness of the effect of acupuncture for migraine. Design. An overview of systematic reviews and meta-analyses (SR/MAs) for randomized controlled trials. Material and Methods. We searched PubMed, Embase, the Cochrane Library, China Knowledge Resource Integrated Database, VIP Chinese Journal Full Text Database, WANFANG Data, and China Biology Medicine disc from their establishment to May 27, 2018. SR/MAs of randomized controlled trials comparing the effect of the acupuncture intervention with another treatment control in migraine patients were included. Results. 428 SRs were identified, and 15 of them were included. Only 4 SR/MAs were assessed by GRADE, which showed certainty of most evidence being low or very low. Assessed by AMSTAR-2, fourteen was critically low rating overall confidence in the results, and 1 was low rating overall confidence in the results. Evidence suggested that acupuncture has a significant advantage of pain improvement, efficacy, and safety relative to blank control, sham acupuncture, or drug treatment, but some of these results are contradictory. Conclusions. We found that acupuncture on treating migraine has the advantage for pain improvement and safety, but the quality of SR/MAs of acupuncture for migraine remains to be improved.

Thin-film piezoelectric-on-silicon acoustic wave resonators are promising for the development of system-on-chip integrated circuits with micro/nano-engineered timing reference. However, in order to realize their large potentials, a further enhancement of the quality factor (Q) is required. In this study, a novel approach, based on a multi-stage phononic crystal (PnC) structure, was proposed to achieve an ultra-high Q. A systematical study revealed that the multi-stage PnC structure formed a frequency-selective band-gap to effectively prohibit the dissipation of acoustic waves through tethers, which significantly reduced the anchor loss, leading to an insertion-loss reduction and enhancement of Q. The maximum unloaded Quof the fabricated resonators reached the value of ?10,000 at 109.85 MHz, indicating an enhancement by 19.4 times.