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A molecular dynamics simulation has been conducted in Ni73Co27 and Ni74Co26 alloys during rapid solidification at the cooling rate of 1 × 1012 K/s. It indicates that two phase transitions occur with twice drops, and the number of FCC increases suddenly in Ni73Co27 alloy. And finally, FCC atoms are dominant with the amount of 92.94% at 300 K, which neatly arranges themselves into the crystalline structure. A lot of topologically close-packed clusters are formed in Ni74Co26 alloy, indicating the formation of metallic glass. The differences between the formations in crystalline hexagon and amorphous pentagon are demonstrated by three-dimensional visualization. [ABSTRACT FROM AUTHOR]

Background: This study aimed to investigate whether tumor volume (TV) is better than diameter for predicting the prognosis of patients with early-stage non-small cell lung cancer (NSCLC) after complete resection. Methods: This study retrospectively reviewed the clinicopathologic characteristics of 274 patients with early-stage NSCLC who had received pretreatment computed tomography (CT) scans and complete resection. TV was semi-automatically measured from CT scans using an imaging software program. The optimal cutoff of TV was determined by X-tile software. Disease-free survival (DFS) and overall survival (OS) were assessed by the Kaplan–Meier method. The prognostic significance of TV and other variables was assessed by Cox proportional hazards regression analysis. Results: Using 3.046 cm3 and 8.078 cm3 as optimal cutoff values of TV, the patients were separated into three groups. A larger TV was significantly associated with poor DFS and OS in the multivariable analysis. Kaplan–Meier curves of DFS and OS showed significant differences on the basis of TV among patients with stage 1a disease, greatest tumor diameter (GTD) of 2 cm or smaller, and GTD of 2–3 cm, respectively. Using two TV cutoff points, three categories of TV were created. In 54 cases (19.7%), patients migrated from the GTD categories of 2 cm or smaller, 2–3 cm, and larger than 3 cm into the TV categories of 3.046 cm3 or smaller, 3.046–8.078 cm3, and larger than 8.078 cm3. Conclusion: TV is an independent prognostic factor of DFS and OS for early-stage NSCLC. The findings show that TV is better than GTD for predicting the prognosis of patients with early-stage NSCLC. [ABSTRACT FROM AUTHOR]

Purpose: Dermoscopy and reflectance confocal microscopy (RCM) are non-invasive methods for diagnosis of malignant skin tumours. The aim of this study was to compare the accuracy of dermoscopy and RCM for the diagnosis of malignant skin tumours. Methods: Systematic electronic literature searches were conducted to include PubMed, Medline, Embase, the Cochrane Library database, and Web of Science, up to 26 April 2016. Pooled additional detection rate (ADR), diagnostic accuracy, and 95% confidence intervals (CIs) were calculated using STATA and Meta-Disc analysis. Results: Eight published studies were included in the analysis, involving 1141 skin lesions, which reported a per-lesion analysis of dermoscopy and RCM. Within the same patient group and at the per-lesion level, RCM significantly increased the detection rate of malignant skin tumours by 7.7% (95% CI 0.01-0.14). The pooled sensitivity of dermoscopy was similar to RCM [88.1% (95% CI 0.85-0.91) vs. 93.5% (95% CI 0.91-0.96)]. The specificity of dermoscopy was significantly lower than that of RCM [52.9% (95% CI 0.49-0.57) vs. 80.3% (95% CI 0.77-0.83)]. The pooled ADR of RCM for melanoma detection was 4.3% (95% CI 0.002-0.08). Pooled sensitivity and specificity of dermoscopy for melanoma detection were 88.4% (95% CI 0.84-0.92) and 49.1% (95% CI 0.45-0.53), respectively. The pooled sensitivity and specificity of RCM were 93.5% (95% CI 0.90-0.96) and 78.8% (95% CI 0.75-0.82), respectively. Conclusions: When compared with dermoscopy, RCM has a significantly greater diagnostic specificity for malignant skin tumours and so could improve their detection rate. [ABSTRACT FROM AUTHOR]

In situ external magnetic field was applied during the synthesis of FePt nanoparticles via a chemical solution method. FePt nanoparticle films were prepared on Si by a drop-coating method with and without a magnetic field. Annealing at 700 °C in reductive atmosphere was explored to obtain ferromagnetic FePt L1 phase. The effect of in situ-applied magnetic field on the structure, morphology, and magnetic properties of FePt nanoparticle films was characterized. It is found that the applied magnetic field during the chemical synthesis of FePt nanoparticles plays a key role in the crystallinity and magnetic property of FePt nanoparticle films. As-synthesized FePt nanoparticles under the magnetic field are monodispersed and can be self-assembled over a larger area by a dropping method. The applied magnetic field during the synthesis of FePt nanoparticles not only significantly improves the nanoparticles' c-axis preferred orientation but also benefits the phase transition of FePt nanoparticles from face-centered cubic to face-centered tetragonal structure during the annealing process. The FePt nanoparticle films derived under magnetic field also show some magnetic anisotropy. [ABSTRACT FROM AUTHOR]

Hydrophilic FePt nanoparticles (NPs) have been embedded into the MgO-matrix systems via a sol-gel process to prevent FePt NPs from aggregating and sintering during the heat-treatment process required for the L1 ordering. The chemically ordered L1-phase FePt can be obtained after annealing at 700 °C for 60 min in atmosphere containing H. The effect of the pH value of MgO collosol and FePt nanocrystal loading amount on the structure, morphology, and magnetic properties of FePt/MgO nanocomposites has been investigated. The neutral pH value of 7 in MgO sol is beneficial to stabilize FePt NPs and obtain higher chemical ordering parameter S for the face-centered tetragonal -FePt/MgO nanocomposites with larger coercivity. The FePt NPs loading amount also plays a key role in tuning the microstructure and magnetic properties of the nanocomposites. The relatively higher FePt NPs loading with FePt/MgO molar ratio (R) of 1:2 leads to relatively perfect hexagonal assembly and pure L1 phase. When the R is 1:5 and 1:10, the MgO-matrix in nanocomposites causes the Fe element loss in FePt NPs along with formation of secondary phases such as magnesioferrite or PtFe during the annealing process. Under optimal processing of neutral pH value of 7 and R of 1:2, the presence of MgO matrix produces more homogeneous microstructures and better magnetic properties with higher room-temperature coercivity ( H = 4.65 kOe). [ABSTRACT FROM AUTHOR]

This study examined the individual, class, and school level variability of the students' science achievement. It was hypothesized that there are school or teacher effects which contribute toward explaining achievement differences, besides the student level differences. Owing to the nested structure of the data in Trends in International Mathematics and Science Study, we used the Hierarchical Linear Modeling methodology. Besides the significant effect of engagement, the teachers' teaching certification in science and the topic coverage were both significant factors as were the effect of school SES and availability of remedial and enrichment programs in science. The study makes a contribution to a better understanding of the opportunity to learn variables at classroom and school level in students' science achievement. [ABSTRACT FROM AUTHOR]

Ventricular assist devices may function as a bridge to recovery or heart transplantation, however, little is known about its mechanisms. This study examined the role of matrix metalloproteinases (MMP)-tissue inhibitors of metalloproteinases (TIMP) axis in the process of recovery after unloading in a rat ischemic-induce heart failure (HF) model. Myocardial infarction model was created with the coronary artery ligation. The infarcted rats hearts were unloaded by heterotopic cardiac transplantation ( n = 14). 2 weeks later, the function of normal and infarcted hearts with or without loading was evaluated by Langendorff perfusion model. The hearts were then harvested and prepared for the study of expression of MMPs and TIMPs. Developed pressure in the unloading group was higher than the loading group ( P = 0.0074). Unloading increased the ratio of TIMP-1-MMP-1(1.38 ± 0.11 vs. 0.76 ± 0.09, P < 0.05), TIMP-2-MMP-2 (1.06 ± 0.10 vs. 0.33 ± 0.07, P < 0.01), TIMP-3-MMP-9(1.07 ± 0.08 vs. 0.59 ± 0.06, P < 0.05). Although MMP-1, 2, 9 were downregulated ( P < 0.01, 0.01, 0.05, respectively), TIMP-2 and TIMP-3 upregulated ( P < 0.01, 0.05, respectively), MMP-7 and TIMP-1 was not affected significantly. The infarcted cardiac function could be improved by unloading. It was attributed to downregulation of MMP-1, 2 and 9, and upregulation of TIMP-2 and -3, and furthermore, the ratio of TIMPs to MMPs was increased, which might be more sensitive than sole MMPs or TIMPs for the judgment of myocardial matrix homeostasis. [ABSTRACT FROM AUTHOR]

Salicylic acid (SA) is required for plant systemic acquired resistance (SAR) to viruses. However, SA-deficient plants adapt to RNA virus infections better, which show a lighter symptom and have less reactive oxygen species (ROS) accumulation. The virus replication levels are higher in the SA-deficient plants during the first 10 days, but lower than the wild-type seedlings after 20 dpi. The higher level of glutathione and ascorbic acid (AsA) in SA-deficient plants may contribute to their alleviated symptoms. Solo virus-control method for mortal viruses results in necrosis and chlorosis, no matter what level of virus RNAs would accumulate. Contrastingly, early and high-dose AsA treatment alleviates the symptom, and eventually inhibits virus replication after 20 days. ROS eliminators could not imitate the effect of AsA, and could neither alleviate symptom nor inhibit virus replication. It suggests that both symptom alleviation and virus replication control should be considered for plant virus cures. [ABSTRACT FROM AUTHOR]

Plant viruses cause many diseases that lead to significant economic losses. However, most of the approaches to control plant viruses, including transgenic processes or drugs are plant-species-limited or virus-species-limited, and not very effective. We introduce an application of jasmonic acid (JA) and salicylic acid (SA), a broad-spectrum, efficient and nontransgenic method, to improve plant resistance to RNA viruses. Applying 0.06 mM JA and then 0.1 mM SA 24 h later, enhanced resistance to Cucumber mosaic virus (CMV), Tobacco mosaic virus (TMV) and Turnip crinkle virus (TCV) in Arabidopsis, tobacco, tomato and hot pepper. The inhibition efficiency to virus replication usually achieved up to 80-90%. The putative molecular mechanism was investigated. Some possible factors affecting the synergism of JA and SA have been defined, including WRKY53, WRKY70, PDF1.2, MPK4, MPK2, MPK3, MPK5, MPK12, MPK14, MKK1, MKK2, and MKK6. All genes involving in the synergism of JA and SA were investigated. This approach is safe to human beings and environmentally friendly and shows potential as a strong tool for crop protection against plant viruses. [ABSTRACT FROM AUTHOR]

This study evaluates the erectile function of male patients treated by preoperative radiotherapy followed by surgery and surgery alone for locally advanced rectal cancer. A total of 112 men treated by total mesorectal excision with autonomic nerve preservation were included. Seventy-three patients were treated by preoperative radiotherapy followed by surgery (RTS group), and 39 were treated by surgery alone (surgery group). Patients filled out the five-item version of the international index of erectile function (IIEF-5) questionnaire at least 6 months after initial erectile function assessment. We analyzed the impact of age, surgery type, location, and size of tumor on erectile function. Total score was decreased significantly at follow-up compared to initial assessment in both RTS and surgery group (20.31 ± 4.39 vs. 11.52 ± 4.83, P = 0.012; 19.86 ± 4.61 vs. 14.07 ± 6.37, P = 0.031, respectively). Score difference was statistically higher in RTS group compared with surgery group ( P = 0.028). In terms of surgery type for RTS group, score difference was statistically higher in the patients with abdominoperineal resection (APR) compared with those with lower anterior resection ( P = 0.023). In comparison of score difference according to tumor location, difference was statistically higher in the patients with lower rectal cancer compared with those with upper rectal cancer ( P = 0.017). The erectile functions of patients treated by preoperative radiotherapy followed by surgery are more affected than that of patients treated by surgery alone in locally advanced rectal cancer. Also APR and lower rectal cancer were significantly associated with erectile dysfunction in the patients treated by preoperative radiotherapy followed by surgery. [ABSTRACT FROM AUTHOR]

Micron grade Sn powder, VG32 oil and active pharmaceutical were mixed and the Nanometer Sn lubricant additives were prepared. Nanometer additives with different Sn concentrations were used in Steel-brass Tribo-pair for friction and wear test. The activating method to nano-Sn and surface of brass samples was investigated, and the method to form relatively thick friction coating on samples was discussed. Surface elemental distribution, coating thickness and its surface appearance were analyzed with X-ray photoelectron spectrum (XPS), auger electron spectrum (AES) and scanning electron microscope (SEM) respectively. The result shows that the ultra-thick friction coating (approx 20 μm), with abundant tin and well combined with substrate, has formed on the brass sample. The friction coating revealed superior performance of friction reducing and anti-wear properties. Therefore, the results possess practical significance to self-repair usage on steel-brass tribo-pair in mechanical systems. [ABSTRACT FROM AUTHOR]

Enhancing the mining speed of a working face has become the primary approach to achieve high production and efficiency in coal mines, thereby further improving the production capacity. However, the problem of rock bursts resulting from this approach has become increasingly serious. Therefore, to implement coal mine safety and efficient extraction, the impact of deformation pressure caused by different mining speeds should be considered, and a reasonable mining speed of the working face should be determined. The influence of mining speed on overlying rock breaking in the stope is analyzed by establishing a key layer block rotation and subsidence model. Results show that with the increasing mining speed, the compression amount of gangue in the goaf decreases, and the rotation and subsidence amount of rock block B above goaf decreases, forcing the rotation and subsidence amount of rock block A above roadway to increase. Consequently, the contact mode between rock block A and rock block B changes from line contact to point contact, and the horizontal thrust and shear force between blocks increase. The increase in rotation and subsidence of rock block A intensifies the compression degree of coal and rock mass below the key layer, thereby increasing the stress concentration degree of coal and rock mass as well as the total energy accumulation. In addition, due to the insufficient compression of gangue in the goaf, the bending and subsidence space of the far-field key layer are limited, the length of the suspended roof increases, and the influence range of mining stress and the energy accumulation range expand. Numerical test results and underground microseismic monitoring results verify the correlation between mining speed and stope energy, and high-energy events generally appear 1–2 d after the change in mining speed. On this basis, the statistical principle confirms that the maximum mining speed of the working face at 6 m/d is reasonable. [ABSTRACT FROM AUTHOR]

To investigate the structural evolution and hereditary mechanism of icosahedral nano-clusters formed during rapid solidification, a molecular dynamics (MD) simulation study has been performed for a system consisting of 107 atoms of liquid Mg70Zn30 alloy. Adopting Honeycutt-Anderson (HA) bond-type index method and cluster type index method (CTIM-3) to analyse the microstructures in the system it is found that for all the nano-clusters including 2~8 icosahedral clusters in the system, there are 62 kinds of geometrical structures, and those can be classified, by the configurations of the central atoms of basic clusters they contained, into four types: chain-like, triangle-tailed, quadrilateral-tailed and pyramidal-tailed. The evolution of icosahedral nano-clusters can be conducted by perfect heredity and replacement heredity, and the perfect heredity emerges when temperature is slightly less than Tm then increase rapidly and far exceeds the replacement heredity at Tg; while for the replacement heredity, there are three major modes: replaced by triangle (3-atoms), quadrangle (4-atoms) and pentagonal pyramid (6-atoms), rather than by single atom step by step during rapid solidification processes. [ABSTRACT FROM AUTHOR]