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[Display omitted] • UNSM repairs the corroded surface and induces compressive residual stresses. • UNSM is effective in rejuvenating the fatigue life of corroded aluminum alloy. • The fatigue life of the rejuvenated samples is comparable to the untreated ones. In this study, ultrasonic nanocrystal surface modification (UNSM) was used to rejuvenate the fatigue performance of pre-corroded 7075-T651 aluminum alloy. The fatigue life of specimens subjected to pre-corrosion and burnishing was found to be only slightly higher than that of corroded specimens, while the fatigue life of the specimens subjected to pre-corrosion and UNSM treatment was twenty times higher than that of the corroded specimens. The findings of this study demonstrate that the repair of the corroded surface layer, surface work-hardening, and beneficial compressive residual stress induced by UNSM are responsible for the fatigue performance rejuvenation of the pre-corroded alloy. [ABSTRACT FROM AUTHOR]

Abstract: The aim of the present study was to investigate the therapeutic effect and mechanism of 3,4-oxo-isopropylidene-shikimic acid (ISA) on 2,4,6-trinitrobenzenesulfonic acid (TNBS)-induced colitis in rats. (50, 100, 200mg/kg) was administered for 14days, 1day after the induction of colitis by TNBS. The colonic injury and inflammation were assessed by macroscopic damage scores and myeloperoxidase (MPO) activity. Malondialdehyde (MDA) and nitric oxide (NO) levels, and superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activities in plasma were measured with biochemical methods. Prostaglandin E2 (PGE2) level in colon was determined by radioimmunoassay. Expressions of inducible nitric oxide synthase (iNOS), cyclo-oxygenase-2 (COX-2), inhibitor kappa B-alpha (IκBα) and nuclear factor kappa B (NF-κB) p65 proteins in the colonic tissue were detected with immunohistochemistry. Enhanced colonic mucosal injury, inflammatory response and oxidative stress were observed in the animals clystered with TNBS, which was manifested as the significant increase in colon mucosal damage index, MPO activity, levels of MDA, NO and PGE2, as well as the expressions of iNOS, COX-2 and NF-κB p65 proteins in the colonic mucosa, and the significant decrease in expressions of IκBα proteins in the colonic mucosa. However, these parameters were found to be significantly ameliorated in rats treated with ISA at given doses, especially at 100mg/kg and 200mg/kg. Administration of ISA may have significant therapeutic effects on experimental colitis in rats, probably due to its mechanism of antioxidation, its inhibition of arachidonic acid metabolism and its modulation of the IκBα/NF-κB p65 expression. [Copyright &y& Elsevier]

The present work was done to investigate the possible effects of 3,4-oxo-isopropylidene-shikimic acid (ISA) on acetic acid (AA)-induced colitis in rats. Colitis was induced by intracolonic injection of 6 % AA. Several parameters, including macroscopic score and biochemical parameters, were determined to assess the degree of protection. Biochemical parameters such as myeloperoxidase (MPO) activity, malondialdehyde (MDA) and nitric oxide (NO) levels, and superoxide dismutase (SOD) and inducible NO synthase (NOS) activities were measured following standard assay procedures. The study showed that treatment of rats for 6 days with ISA (100 and 200 mg/kg) was able to give complete protection against AA-induced colitis. Moreover, biochemical changes were reversed and brought toward control. These results suggest a beneficial effect of ISA against experimental colitis and the possible mechanism of the protective effects may be partly due to an antioxidant action. [ABSTRACT FROM AUTHOR]

After publication of the original article [1], the authors have reported that the software developers had used a new amended version of the software called "v0.9.5.10" instead of "v0.9.5.5", which is referred to in the original article. [ABSTRACT FROM AUTHOR]

[Display omitted] • UNSM refined the martensite laths and formed a plastically deformed layer on A100 steel. • Higher surface hardness and higher fretting wear resistance were observed. • High magnitude compressive residual stresses were generated in the near surface region. • Both the plain fatigue and fretting fatigue resistance of A100 steel were improved. In this study, ultrasonic nanocrystal surface modification (UNSM) was used to improve plain and fretting fatigue properties of A100 steel. Results showed that an obvious plastic deformation layer was induced in A100 steel, and the martensite microstructure was remarkably refined. In addition, surface compressive residual stress after UNSM treatment was enhanced to 1700 MPa due to the severe lattice distortion. The increased surface hardness and the presence of beneficial compressive residual stresses after UNSM treatment significantly enhanced the plain/fretting fatigue resistance of A100 steel by retarding fatigue crack nucleation and propagation. [ABSTRACT FROM AUTHOR]

Gradient nanocrystalline (GNC) metals exhibit an unprecedented combination of high strength and high ductility. In this study, GNC copper was obtained using ultrasonic nanocrystalline surface modification (UNSM), and its plasticity mechanism was investigated using tensile tests. It was found that UNSM treatment can grant copper superior yield strength and ductility which is beyond the capacity of conventional cold-working. Moreover, the UNSM-treated copper has a reduced strain-hardening capacity which does not lead to early necking and deteriorated ductility. The strain energy analysis shows that the yield strength of GNC material can be estimated using the root mean square of yield strengths of the coarse-grained (CG) layer and the gradient structure (GS) layer. The strain energy analysis also predicted a strong interaction between GS layer and CG layer during tensile deformation. Furthermore, a dislocation-based constitutive model was applied to understand the interaction between CG layer and GS layer. The migration of dislocations from the CG layer to the GS layer was proposed to explain the interaction. The migration of dislocations induces strain softening and, thus, releases internal strain energy. The proposed mechanism is supported by our experimental observations: the reduction in strain-hardening capacity is positive-related to the depression in strain localization in UNSM-treated GNC copper. The improved ductility is attributed to the depressed strain localization and the refreshed capacity for dislocation accumulation, both resulted from dislocation migration from the CG layer to the GS layer. • A constitutive model based on dislocation dynamics to study the plasticity of gradient nanocrystalline metals. • Dislocation kinetics drives dislocation migration from the coarse-grained layer and the gradient structure layer. • Strain softening induced by dislocation migration prevented early necking of the gradient structured materials. • A design criterion to achieve both high strength and ductility for gradient nanocrystalline materials. [ABSTRACT FROM AUTHOR]

• An UNSM system is used to fabricate hierarchical surface structures on metals. • The formation of nano-scale structure originates from pile-up produced by dynamic indentation. • Dynamic indentation produces higher pile-up as compared with quasi-static indentation. • Dynamic indentation induces high resistance to dislocation motion, forcing material to pile up. Ultrasonic-assisted surface texturing can produce surface textures with hierarchical micro/nano-scale structures on metal components. In this work, we prove that the formation of nano-scale structure originates from pile-up produced by ultrasonic dynamic indentation. Both quasi-static and dynamic indentations are performed on pure copper, 316 stainless steel, and pure titanium using an ultrasonic nanocrystal surface modification system. For the first time, it is revealed that ultrasonic dynamic indentation produces significant higher pile-up as compared with that of quasi-static indentation, making nanoscale structure possible. Finite element simulations demonstrate that dynamic indentation produces larger equivalent plastic strain, an indicator for work hardening, in the region close to the edge of the contact interface. It is conjectured that higher degrees of work hardening and dislocation density result in a higher dislocation resistance as compared with quasi-static indentation. The plastic deformation is confined at the contact interface and is then forced to move upward, leading to a significant pile-up. [ABSTRACT FROM AUTHOR]

Background: Squamous cell carcinoma (SCC) is a main pathological type of non-small cell lung cancer. It is common among elderly patients with poor prognosis. We aimed to establish an accurate nomogram to predict survival for elderly patients (≥ 60 years old) with SCC based on the Surveillance, Epidemiology, and End Results (SEER) database.Methods: The gerontal patients diagnosed with SCC from 2010 to 2015 were collected from the Surveillance, Epidemiology, and End Results (SEER) database. The independent prognostic factors were identified using multivariate Cox proportional hazards regression analysis, which were utilized to conduct a nomogram for predicting survival. The novel nomogram was evaluated by Concordance index (C-index), calibration curves, net reclassification improvement (NRI), integrated discrimination improvement (IDI), and decision curve analysis (DCA).Results: 32,474 elderly SCC patients were included in the analysis, who were randomly assigned to training cohort (n = 22,732) and validation cohort (n = 9742). The following factors were contained in the final prognostic model: age, sex, race, marital status, tumor site, AJCC stage, surgery, radiation and chemotherapy. Compared to AJCC stage, the novel nomogram exhibited better performance: C-index (training group: 0.789 vs. 0.730, validation group: 0.791 vs. 0.733), the areas under the receiver operating characteristic curve of the training set (1-year AUC: 0.846 vs. 0.791, 3-year AUC: 0.860 vs. 0.801, 5-year AUC: 0.859 vs. 0.794) and the validation set (1-year AUC: 0.846 vs. 0.793, 3-year AUC: 0.863 vs. 0.806, 5-year AUC: 0.866 vs. 0.801), and the 1-, 3- and 5-year calibration plots. Additionally, the NRI and IDI and 1-, 3- and 5-year DCA curves all confirmed that the nomogram was a great prognosis tool.Conclusions: We constructed a novel nomogram that could be practical and helpful for precise evaluation of elderly SCC patient prognosis, thus helping clinicians in determining the appropriate therapy strategies for individual SCC patients. [ABSTRACT FROM AUTHOR]

• A refined and distorted lath martensite structure was generated on the surface of 300M steels through UNSM. • UNSM significantly induced high surface hardness and compressive residual stresses. • UNSM treated 300M steels exhibited higher wear resistance by forming a surface plastic deformation layer. In this study, the effects of ultrasonic nanocrystal surface modification (UNSM) treatment on the surface integrity, microstructures and wear resistance of 300M ultra-high strength steel (300M steel) were investigated. The results showed that surface roughness of 300M steels after UNSM processing was significantly decreased with a lower scanning speed even though the surface roughness values were higher than that of mechanically polished control samples. In addition, the surface hardness of 300M steel was significantly enhanced as the static load increased. It was found that using a static load of 50 N and a scanning speed of 250 mm/min in the UNSM process can significantly improve surface hardness (797 HV) while slightly increasing the surface roughness. With these parameters, the resulting microstructure of UNSM-processed samples have three layers: the layer of severe plastic deformation, the layer with gradual plastic deformation, and the unaffected layer. Due to the plastic deformation, greater and deeper compressive residual stresses were induced in the UNSM-processed samples. In addition, the wear resistance of UNSM-processed samples was significantly improved, which was attributed to the refined martensite laths, work hardening and compressive residual stress. [ABSTRACT FROM AUTHOR]

• Low molecular weight heparin-loaded nanoparticles (LMWH-loaded NPs) are prepared. • LMWH-loaded NPs are used for oral therapy of ulcerative colitis (UC). • NPs are designed based on the surface charge characteristics of inflamed mucosa. • SA-TMC-NPs have desirable mucoadhesion and colon-targeting property. • SA-TMC-NPs improve the therapeutic effects of LMWH on UC in colitis mice. Low molecular weight heparin (LMWH) is reported to have therapeutic action on ulcerative colitis (UC). To facilitate its oral administration and improve the colon-targeting property, LMWH-loaded nanoparticles (TMC-NPs and SA-TMC-NPs) are prepared and evaluated by a series of studies, including their stabilities, drug release profiles, mucosal permeation, mucoadhesion, cytotoxicities, cellular uptake profiles, anticoagulant and anti-inflammatory activities, mucosal healing properties, biosafety and ameliorative effects on experimental colitis. Consequently, oral administration of LMWH-loaded NPs for 5 days perform significant therapeutic effects on mice, which are manifested as improved body weight gains, colon length, DAI score, MPO activity and histological characteristics. Besides, SA-TMC-NPs show better colon-targeting property than TMC-NPs that is demonstrated by lower oral absorption (ATPP 38.95 s) and stronger mucoadhesion (kcps reduces 36.46 %) to inflamed colon tissues. Therefore, TMC-based NPs are proved to be as promising oral colon-targeting drug delivery systems of LMWH and has potential application in UC treatment. [ABSTRACT FROM AUTHOR]

The tribological performance of AISI 52100 substrates subjected to several surface treatments have been evaluated in rolling, sliding, and mixed mode contact. The surface treatments include a boron-doped diamond-like carbon (B-DLC) coating deposited by plasma-assisted magnetron sputtering, an ultrasonic nanocrystal surface modification (UNSM) technique used to generate severe plastic deformation in the near surface of the steel specimens, and a B-DLC coating applied to a UNSM pretreated surface. In general, the tribological performance of the duplex surface treatment was superior to that of the untreated specimens and of the specimens with the other surface treatments in rolling, sliding, and mixed mode contact. The improved tribological performance of the duplex process was attributed to the combination of increased wear resistance provided by the B-DLC coating and the grain refinement of the martensitic structure of the AISI 52100 imparted by the UNSM process that created a beneficial substrate/coating interface. • UNSM treatment was carried out on the 52,100 substrates before B-DLC coating. • The reduction of hardness/modulus mismatch through UNSM resulted in higher adhesion between the substrate and the B-DLC coating. • B-DLC coating resulted in improved tribological performance in rolling, sliding and mixed mode contact. • The combination of UNSM treatment and B-DLC coating results in best rolling contact fatigue performance. • Grain refinement and compressive residual stresses contributed to rolling contact fatigue performance improvement. [ABSTRACT FROM AUTHOR]

In this study, electropulsing-assisted ultrasonic nanocrystal surface modification (EP-UNSM) was used to process 300M steel. It has been demonstrated that pulsed current can more effectively improve the plasticity of 300M steel as compared to continuous current having the same effective current density, even though the bulk temperature (around 150 °C) and thus the thermal effect is the same. It is believed that a pulsed current, which has a much higher peak current density, can more effectively activate pinned dislocations and can better assist the deformation-based surface modification process. EP-UNSM treatment of the steel resulted in much higher surface hardness and greater plastically affected depth as compared to both UNSM and continuous current-assisted UNSM (CC-UNSM). As a result, EP-UNSM treatment imparted much higher wear resistance to the steel than either UNSM or CC-UNSM treatment. It has been demonstrated that pulsed current can effectively improve the process effectiveness of the selected deformation-based surface engineering process (UNSM) without significantly increasing the temperature. Unlabelled Image • EP-UNSM resulted in much higher surface hardness and thicker hardened layer compared with UNSM and CC-UNSM. • Pulsed current can more effectively improve the plasticity of 300M steel compared with continuous current. • Pulsed current can improve the process efficiency of UNSM without a significant temperature increase. [ABSTRACT FROM AUTHOR]

Teeter Bed Separators (TBS) are liquid–solid fluidized beds that are widely used in separation of coarse particles in coal mining industry. The coal particles settle in the self-generating medium bed resulting in separation according to density. Due to the existence of self-generating medium beds, it is difficult to study the sedimentation of particles in TBS through experiments and detection methods. In the present research, a model was built to investigate the bed expansion characteristics with water velocity based on the Euler–Euler approach, and to investigate the settling of foreign particles through bed based on the Euler–Lagrange approach in TBS. Results show that the separation of in TBS should be carried out at low water velocity under the condition of stable fluidized bed. Large particles have a high slip velocity, and they are easily flowing through the bed into the light product leading to a mismatch. The importance of self-generating bed on separation of particle with narrow size ranges are clarified. The model provides a way for investigating the separation of particles in a liquid–solid fluidized bed and provides suggestions for the selection of operation conditions in TBS application. [ABSTRACT FROM AUTHOR]

Background: Infections due to methicillin-resistant Staphylococcus aureus (MRSA) cause serious health risks and significant economic burdens and the preferred drugs are still controversial. Methods: We performed a network meta-analysis (NMA) to compare the efficacy and safety of antibiotics used to treat inpatients with complicated skin and soft structure infections (cSSSI) or hospital-acquired or ventilator-associated pneumonia (HAP/VAP). We also developed a decision tree model to assess the cost-effectiveness of antibiotics. Results: Forty-nine randomized controlled trials met the inclusion criteria (34 for cSSSI, 15 for HAP/VAP) and compared the efficacy and safety of 16 antibiotics. For cSSSI, NMA indicated that for clinical cure, linezolid was superior than vancomycin (odds ratio (OR) 1.55, 95% confidence interval (CI) 1.19–2.02), while tedizolid (OR 1.39, CI 0.70–2.76) was similar to vancomycin. In terms of safety, there were no significant differences between any two interventions on total adverse events. Based on drug and hospital costs in America, the incremental cost-effectiveness ratios (ICERs) per life-year saved for linezolid and tedizolid compared with vancomycin were US$2833 and US$5523. For HAP/VAP, there were no significant effects either for clinical cure or for safety endpoints between linezolid and vancomycin in NMA. ICERs per life-year saved for linezolid compared with vancomycin were US$2185. Conclusion: In these clinical trials, considering efficacy, safety, and cost-effectivenes, linezolid and tedizolid showed their superiority in MRSA cSSSI; while linezolid might be recommended to treat MRSA pneumonia. Although vancomycin was not cost-effective in pharmacoeconomic evaluation, it is still the first-line treatment for MRSA infection in the clinical practice. This study might provide new insights of therapeutic choices for patients with MRSA infections whilst awaiting the arrival of higher quality evidence. [ABSTRACT FROM AUTHOR]

Abstract Using either electropulsing (EP) or surface severe plastic deformation (SSPD) to process metallic glasses can improve their plasticity, however, the moderate improvement in plasticity does not warrant a commercial usage. This work, for the first time, demonstrates the integration of electropulsing and surface severe plastic deformation is much more effective in improving the plasticity of metallic glasses than EP or SSPD treatment alone, opening a new avenue towards an unprecedented combination of strength and plasticity in metallic glasses. It is found that SSPD can generate microstructure heterogeneity featured by a mixture of matrix and plastically displaced regions with increased atomic volume. When applying EP and SSPD simultaneously, a synergistic effect occurs to produce a hybrid network with excess free volume and nanocrystals uniformly embedded in amorphous matrix. Molecular dynamics simulation and fracture surface analysis further reveal that the hybrid network is able to effectively reduce shear band localization, and therefore delay the fracture of metallic glasses. Graphical abstract Unlabelled Image Highlights • Electropulsing-assisted surface severe plastic deformation (EP-SSPD) treatment increased plasticity from 0% to 2.03% ± 0.29%. • EP-SSPD generated a hybrid structure of 4.1% uniformly-distributed nanocrystals and 0.009% averaged extra free volume. • Free volume alleviates localized strain at nanocrystal/matrix interface and nanocrystals retard shear band propagation. [ABSTRACT FROM AUTHOR]

Background: China launched a 3-year rectification scheme for the clinical use of antibiotics in 2011, and a specific scheme for carbapenem use in 2017. The aim of this study was to investigate the effects of government policies on carbapenem use, and their correlation with carbapenem-resistant Pseudomonas aeruginosa (CRPA). Methods: The study was divided into four stages: preintervention (2010), antimicrobial programme (2011–2013), post-antimicrobial programme (2014–2016) and carbapenem programme (2017). A point-score system was proposed for evaluating the rationality of carbapenem use, and evaluated based on the indications, microbial culture, single dose, interval, and duration. Any prescription without a global score of 10 points was judged as irrational. The trend was analyzed by regression analysis, and Spearman correlation analysis was used for testing the correlation. Findings: The rate of rational use of carbapenems was 29.7% in 2010, and increased by 55.5, 45.2, and 51.5% during the subsequent three stages. The rationality declined slightly during the post-antimicrobial programme (2014–2016) while the consumption of carbapenems was markedly increased. These two parameters improved slightly in 2017. Moreover, the prevalence of CRPA was significantly negatively correlated with the rate of rational carbapenem use (Coefficient = − 0.553, P < 0.05), and not with the consumption of carbapenems (P > 0.05). Conclusions: The rational application of carbapenems was related to government policies in this study, with irrational carbapenem use possibly related to the development of CRPA. The current point-score system could be a useful tool for performing assessments. [ABSTRACT FROM AUTHOR]

Background: Invasive pulmonary aspergillosis (IPA) is a life-threatening disease in immunosuppressed patients. Voriconazole is commonly used to prevent and treat IPA in the clinic, but the optimal prophylactic antifungal regimen is unknown. The objective of this study was to clarify the mechanism underlying how voriconazole prevents IPA based on a target cellular pharmacokinetics/pharmacodynamics model, with the aim of identifying a way to design an optimal prophylactic antifungal regimen.Methods: A nystatin assay was used to establish a target-cells model for A. fumigatus infection. An inhibitory effect sigmoid Emax model was developed to explore the cellular PK/PD breakpoint, and Monte Carlo simulation was used to design the prophylactic antifungal regimen.Results: The intracellular activity of voriconazole in the target cells varied with its concentration, with the minimum inhibitory concentration (MIC) being an important determinant. For A. fumigatus strains AF293 and AF26, voriconazole decreased the intracellular inoculum by 0.79 and 0.84 lg cfu, respectively. The inhibitory effect sigmoid Emax model showed that 84.01% of the intracellular inoculum was suppressed by voriconazole within 24 h, and that a PK/PD value of 35.53 for the extracellular voriconazole concentration divided by MIC was associated with a 50% suppression of intracellular A. fumigatus. The Monte Carlo simulation results showed that the oral administration of at least 200 mg of voriconazole twice daily was yielded estimated the cumulative fraction of response value of 91.48%. Concentration of voriconazole in the pulmonary epithelial lining fluid and the plasma of > 17.77 and > 1.55 mg/L, respectively, would ensure the PK/PD > 35.53 for voriconazole against most isolates of A. fumigatus and may will be benefit to prevent IPA in clinical applications.Conclusions: This study used a target cellular pharmacokinetics/pharmacodynamics model to reveal a potential mechanism underlying how voriconazole prevents IPA and has provided a method for designing voriconazole prophylactic antifungal regimen in immunosuppressed patients. [ABSTRACT FROM AUTHOR]