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The low-velocity impact behaviors of DP590/AA6061 self-piercing riveting (SPR) joints are studied at the impact energies of 5 J, 10 J, 20 J, 30 J, and room temperature (25 °C). The lap shear and fatigue tests, and the cross-sectional microscopies of joints are used to assess the mechanical property evolutions of the joints after low-velocity impact. The results show that the absorbed impact energies of SPR joints reach the critical value at an impact energy of 30 J, the exceeded impact energy causes crack failures in the sheets and decreases the interlocking performance of the joints. The static property and the absorbed energy of the SPR joints are reduced by 16% and 36% when the joints are impacted at 30 J, respectively. The low-velocity impacts do not change the failure forms of the joints, but significantly reduce the mechanical interlocking properties of the joints. The fatigue lives of the SPR joints are reduced due to low-velocity impact, and the impacted joints are more sensitive to cyclic loadings.

Osteosarcoma, the most common primary tumor of the bones, causes many deaths due to its rapid proliferation and drug resistance. Recent studies have shown that cyclin D1 plays a key regulatory role during cell proliferation, and non-coding microRNAs (miRNAs) act as crucial modulators of cyclin D1 (CCND1). The aim of the current study was to determine the role of miRNAs in controlling CCND1 expression and inducing cell apoptosis. CCND1 has been found to be a target of miR-15a and miR-16-1 through analysis of complementary sequences between microRNAs and CCND1 mRNA. The upregulation of miR-15a and miR-16-1 in the cell line SOSP-9607 induces apoptosis and cell cycle arrest. Osteosarcoma cells transfected with miR-15a and miR-16-1 show slower proliferation curves. Moreover, the transcription of CCND1 is suppressed by miR-15a and miR-16-1 via direct binding to the CCND1 3′-untranslated region (3′-UTR). The data presented here demonstrate that the CCND1 contributes to osteosarcoma cell proliferation, suggesting that repression of CCND1 by miR-15a and miR-16-1 could be used for osteosarcoma therapy.

Atom-thick two-dimensional materials usually possess unique properties compared to their bulk counterparts. Their properties are significantly affected by defects, which could be uncontrollably introduced by irradiation. The effects of electromagnetic irradiation and particle irradiation on 2H MoS 2 two-dimensional nanolayers are reviewed in this paper, covering heavy ions, protons, electrons, gamma rays, X-rays, ultraviolet light, terahertz, and infrared irradiation. Various defects in MoS 2 layers were created by the defect engineering. Here we focus on their influence on the structural, electronic, catalytic, and magnetic performance of the 2D materials. Additionally, irradiation-induced doping is discussed and involved.

To evaluate the efficacy of ketamine in preventing propofol injection pain in children. Prospective, randomized, double-blinded, placebo-controlled study. University-affiliated hospital. 192 ASA physical status 1 and 2 pediatric patients. Patients were randomly assigned to 4 groups. Group S (control) received normal saline as a placebo; Group K1, Group K3, and Group K5 received 0.1 mg/kg, 0.3 mg/kg, and 0.5 mg/kg of ketamine, respectively. Fifteen seconds after the ketamine injection, patients were injected with propofol at a rate of 12 mL/min until loss-of-eyelash reflex. Pain was evaluated blindly at the time of induction using a 4-point scale: 0 = no pain, 1 = mild pain, 2 = moderate pain, and 3 = severe pain. Adverse effects were recorded. Characteristics of induction of anesthesia, such as dose of propofol and time from propofol injection to loss of consciousness (induction duration), were noted. 39 (84.8%) Group S (control) patients had pain. Pretreatment with ketamine reduced the frequency of pain significantly to 56.5%, 17.0%, and 14.9% in Groups K1, K3, and K5, respectively. Furthermore, the frequency of moderate and severe pain in Group K1 (21.8%), Group K3 (6.4%), and Group K5 (4.3%) was significantly (P < 0.001, respectively) reduced compared with Group S (76.1%). Moreover, the dose of propofol for induction in Group K5 was smaller than in Group S, Group K1, and Group K3 (P < 0.05). One patient in Group K5 had emergence agitation. Pretreatment with a small dose of ketamine (0.3 mg/kg) reduced the frequency and intensity of propofol injection pain without severe adverse effects.

Objective: To compare the hemodynamics after combined spinal-epidural anesthesia (CSEA) between decubitus and sitting positions in aged patients undergoing total hip replacement. Methods: A total of 80 aged patients who underwent CSEA for elective total hip replacement were randomly divided into a decubitus position group (group D) and a sitting position group (group S; each group with 40 patients). In group D, 10 mg of 0.5% bupivacaine were given into the subarachnoid space in decubitus position. In group S, 10 mg of 0.5% bupivacaine were given into the subarachnoid space in the sitting position, which was maintained for 1 min, after which the patients were in decubitus position. In both groups, the sensory block levels and changes in hemodynamics were assessed. Results: The mean arterial blood pressure was significantly higher in group S than in group D at each time point within 30 min after anesthesia. There were no significant differences in heart rate between the two groups at each time point. There was also no significant difference in the level of sensory block between the two groups 20 min after the administration of CSEA. Conclusion: For aged patients undergoing total hip replacement, CSEA is safer and more effective in the sitting position than in decubitus position.

The effects of rare-earth element Y in refining impure copper were investigated in this paper. The composition, microstructures, and corrosion resistance properties of impure copper before and after refinement with Y were investigated using direct-reading spectrometry, inductively coupled plasma atomic emission spectrometry, optical microscopy, scanning electron microscopy, and potentiodynamic polariza- tion measurements. The results show that the concentrations of impurities S, As, Sb, Bi, A1, Cd, and Se are remarkably decreased. Adding an appropriate amount of Y refines the microstructure and enhances the corrosion resistance properties of impure copper in HC1 solution via a purification effect. The formation enthalpies of compounds formed between Y and various impurity elements were calculated on the basis of Miedema＇s theory. The thermodynamic mechanisms of the refinement of impure copper by Y were also discussed.

Background： Despite its high prevalence, morbidity, and mortality, sepsis-associated encephalopathy （SAE） is still poorly understood. The aim of this prospective and observational study was to investigate the clinical significance of calcium-binding protein A8 （S 100AS） in serum and tumor necrosis factor receptor-associated factor 6 （TRAF6） in peripheral blood mononuclear cells （PBMCs） in diagnosing SAE and predicting its prognosis. Methods： Data of septic patients were collected within 24 h after Intensive Care Unit admission fi-om July 2014 to March 2015. Healthy medical personnel served as the control group. SAE was defined as cerebral dysfhnction in the presence of sepsis that fulfilled the exclusion criteria. The biochemical indicators, Glasgow Coma Scale, Acute Physiology and Chronic Health Evaluation score II, TRAF6 in PBMC, serum S 100A8, S 10013, and neuron-specific enolase were evaluated in SAE patients afresh. TRAF6 and S 100A8 were also measured in the control group. Results： Of the 57 enrolled patients, 29 were diagnosed with SAE. The S 100A8 and TRAF6 concentrations in SAE patients were both significantly higher than that in no-encephalopathy （NE） patients, and higher in NE than that in controls （3.74 ± 3.13 vs. 1.08 ± 0.75 vs. 0.37 ± 0.14 ng/ml, P 〈 0.01 ; 3.18 ± 1.55 vs. 1.02 ± 0.63 vs. 0.47 ± 0.10, P 〈 0.01）. S 100A8 levels of 1.93 ng/ml were diagnostic of SAE with 92.90% specificity and 69.00% sensitivity in the receiver operating characteristic （ROC） curve, and the area under the curve was 0.86 （95% confidence interval [CI]： 0.76-0.95）. TRAF6-relative levels of 1.44 were diagnostic of SAE with 85.70% specificity and 86.20% sensitivity, and the area under the curve was 0.94 （95% CI： 0.88-0.99）. In addition, S 100A8 levels of 2.41 ng/ml predicted 28-day mortality of SAE with 90.00% specificity and 73.70% sensitivity in the ROC curve, and the area under the curve was 0.88. TRAF6 relative levels of 2.94 predicted 28-day mortality of SAE with 80.00% specificity and 68.40% sensitivity, and the area under the curve was 0.77. Compared with TRAF6, the specificity of serum S 100A8 in diagnosing SAE and predicting mortality was higher, although the sensitivity was low. In contrast, the TRAF6 had higher sensitivity for diagnosis. Conclusions： Peripheral blood levels of S 100A8 and TRAF6 in SAE patients were elevated and might be related to the severity of SAE and predict the outcome of SAE. The efficacy and specificity of S 100A8 for SAE diagnosis were superior, despite its weak sensitivity. S100A8 might be a better biomarker for diagnosis of SAE and predicting prognosis.

Pituicytoma is a distinct low-grade glioma arising from pituicytes of the neurohypophysis and infundibulum. Due to the rarity of this tumor, most of the reported cases in the literature were originally misdiagnosed as pituitary adenoma, meningiomas, and craniopharyngioma. It is of vital importance to accurately identify this tumor because this tumor, unlike pituitary adenomas, is prone to heavy bleeding during the surgical resection.

The continuous casting process is used for solidifying molten steel into semi-finished steel. The technology of secondary cooling is extremely important for output of the casting machine and billet quality. A dynamic water model was introduced, including solidification model in the secondary cooling, feedforward control strategy based on continuous temperature measurement in tundish, and feedback control strategy based on surface temperature measurement. The mathematical model of solidification process was developed according to the principle of solidification, and the solidification model was validated by measuring billet shell thickness through shooting nail and sulfur print. Primary water distribution was calculated by the solidification model according to procedure parameters, and it was adjusted by the other two control strategies online. The model was applied on some caster and billet quality was obviously improved, indicating that the dynamic water model is better than conventional ones.