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Purpose Surface mount technology (SMT) is widely used and plays an important role in electronic equipment. The purpose of this paper is to reveal the effects of interface cracks on the fatigue life of SMT solder joint under service load and to provide some valuable reference information for improving service reliability of SMT packages. Design/methodology/approach A 3D geometric model of SMT package is established. The mechanical properties of SMT solder joint under thermal cycling load and random vibration load were solved by 3D finite element analysis. The fatigue life of SMT solder joint under different loads can be calculated by using the modified Coffin–Manson model and high-cycle fatigue model. Findings The results revealed that cracks at different locations and propagation directions have different effect on the fatigue life of the SMT solder joint. From the location of the cracks, Crack 1 has the most significant impact on the thermal fatigue life of the solder joint. Under the same thermal cycling conditions, its life has decreased by 46.98%, followed by Crack 2, Crack 4 and Crack 3. On the other hand, under the same random vibration load, Crack 4 has the most significant impact on the solder joint fatigue life, reducing its life by 81.39%, followed by Crack 1, Crack 3 and Crack 2. From the crack propagation direction, with the increase of crack depth, the thermal fatigue life of the SMT solder joint decreases sharply at first and then continues to decline almost linearly. The random vibration fatigue life of the solder joint decreases continuously with the increase of crack depth. From the crack depth of 0.01 mm to 0.05 mm, the random vibration fatigue life decreases by 86.75%. When the crack width increases, the thermal and random vibration fatigue life of the solder joint decreases almost linearly. Originality/value This paper investigates the effects of interface cracks on the fatigue life and provides useful information on the reliability of SMT packages.

OBJECTIVE To determine the effect of metformin on marrow adiposity in postmenopausal women with newly diagnosed type 2 diabetes mellitus (T2DM). METHODS We enrolled 25 postmenopausal T2DM women who satisfied the requirement of having been on 1 year of metformin therapy and 26 age-matched healthy women receiving a placebo. All participants were analyzed for marrow fat fraction (FF) by magnetic resonance spectroscopy, vertebral volumetric bone mineral density (vBMD) by quantitative computed tomography, blood glucose, lipid profiles, and bone biomarkers to compare values before and after the interventions. Differences between groups were assessed using a Student's t test and chi-square test or an analysis of covariance adjusted for covariates. Twelve-month change in within-group difference was assessed using paired t tests. Correlations were determined by Pearson's correlation. RESULTS Vertebral vBMD was lower in T2DM than in nondiabetic controls (105.6 ± 13.8 vs 112.8 ± 15.2 mg/cm; P = 0.029). T2DM women had a higher marrow FF than those without diabetes (66.3 ± 7.2% vs 58.9 ± 7.5%; P

Objective To explore the role of miR-223 and miR-126 in predicting treatment responses to dual antiplatelet therapy (DAPT) in patients with ST-elevation myocardial infarction (STEMI). Methods Plasma miR-223 and miR-126 levels were measured before treatment. Treatment responses and 2-year survival were determined. In vitro experiments were performed to explore the mechanism of action. Results Patients with resistance to DAPT had a lower level of miR-223 and miR-126. Cardiac-event-free survival was shorter in patients with lower miR-223 or miR-126 levels. MiR-223 and miR-126 independently predicted DAPT resistance. Modulating miR-223 or miR-126 in platelets in vitro significantly changed the response to clopidogrel by regulating platelet aggregation. Conclusion MiR-223 and miR-126 play a role in DAPT resistance and may provide potential biomarkers in patients with STEMI.

Early diagnosis and noninvasive detection of liver fibrosis and its heterogeneity remain as major unmet medical needs for stopping further disease progression toward severe clinical consequences. Here we report a collagen type I targeting protein-based contrast agent (ProCA32.collagen1) with strong collagen I affinity. ProCA32.collagen1 possesses high relaxivities per particle (r1 and r2) at both 1.4 and 7.0 T, which enables the robust detection of early-stage (Ishak stage 3 of 6) liver fibrosis and nonalcoholic steatohepatitis (Ishak stage 1 of 6 or 1 A Mild) in animal models via dual contrast modes. ProCA32.collagen1 also demonstrates vasculature changes associated with intrahepatic angiogenesis and portal hypertension during late-stage fibrosis, and heterogeneity via serial molecular imaging. ProCA32.collagen1 mitigates metal toxicity due to lower dosage and strong resistance to transmetallation and unprecedented metal selectivity for Gd3+ over physiological metal ions with strong translational potential in facilitating effective treatment to halt further chronic liver disease progression. Non-invasive early diagnosis of liver fibrosis is important to prevent disease progression and direct treatment strategies. Here the authors developed a collagen-targeting contrast agent for the detection of early stage fibrosis and non-alcoholic steatohepatitis by magnetic resonance and tested it in animal models.

Detecting bursts in water distribution systems, as anomalies from normal daily usage, is of critical importance for urban infrastructure maintenance. Existing methods based on conventional statistical process control fall short of accurate estimations of burst magnitude and starting time. This research combines a functional basis expansion of water flow data stream and a penalized decomposition to parameterize and estimate the normal water usage profile and detect spars burst with a comparatively small magnitude. The effectiveness of the proposed method is demonstrated by a high-fidelity simulation case study.

Summary Cancer cells alter their nutrition metabolism to cope the stressful environment. One important metabolism adjustment is that cancer cells activate glutaminolysis in response to the reduced carbon from glucose entering into the TCA cycle due to inactivation of several enzymes in glycolysis. An important question is how the cancer cells coordinate the changes of glycolysis and glutaminolysis. In this report, we demonstrate that the pyruvate kinase inactive dimer PKM2 facilitates activation of glutaminolysis. Our experiments show that growth stimulations promote PKM2 dimer. The dimer PKM2 plays a role in regulation of glutaminolysis by upregulation of mitochondrial glutaminase I (GLS-1). PKM2 dimer regulates the GLS-1 expression by controlling internal ribosome entry site (IRES)-dependent c-myc translation. Growth stimulations promote PKM2 interacting with c-myc IRES-RNA, thus facilitating c-myc IRES-dependent translation. Our study reveals an important linker that coordinates the metabolism adjustment in cancer cells., Graphical Abstract, Highlights • PKM2 coordinates cancer cell glucose and glutamine metabolism under growth stimulations • PKM2 controls cancer cell metabolism by regulating GLS and c-myc expression • PKM2 regulates c-Myc IRES-dependent translation • PKM2 dimer facilitates assembly of hnRNP K/L into c-Myc IRES complex, Biological Sciences; Cell Biology; Cancer

Neutrophils infiltration/activation following wound induction marks the early inflammatory response in wound repair. However, the role of the infiltrated/activated neutrophils in tissue regeneration/proliferation during wound repair is not well understood. Here, we report that infiltrated/activated neutrophils at wound site release pyruvate kinase M2 (PKM2) by its secretive mechanisms during early stages of wound repair. The released extracellular PKM2 facilitates early wound healing by promoting angiogenesis at wound site. Our studies reveal a new and important molecular linker between the early inflammatory response and proliferation phase in tissue repair process.

1-(3,5-Dimethoxyphenyl)-4-[(6-fluoro-2-methoxyquinoxalin-3-yl)aminocarbonyl] piperazine (RX-5902) exhibits strong growth inhibition in various human cancer cell lines with IC50 values ranging between 10 and 20 nM. In this study, we demonstrate that p68 RNA helicase is a cellular target of RX-5902 by the drug affinity responsive target stability (DARTS) method, and confirmed the direct binding of 3H-labeled RX-5902 to Y593 phospho-p68 RNA helicase. We further demonstrated RX-5902 inhibited the β-catenin dependent ATPase activity of p68 RNA helicase in an in vitro system. Furthermore, we showed that treatment of cancer cells with RX-5902 resulted in the downregulation of the expression of certain genes, which are known to be regulated by the β-catenin pathway, such as c-Myc, cyclin D1 and p-c-Jun. Therefore, our study indicates that the inhibition of Y593 phospho-p68 helicase - β-catenin interaction by direct binding of RX-5902 to Y593 phospho-p68 RNA helicase may contribute to the anti-cancer activity of this compound. J. Cell. Biochem. 116: 1595–1601, 2015. © 2015 Wiley Periodicals, Inc.

It is long known that pyruvate kinase isoform M2 (PKM2) is released into the circulation of cancer patients. The PKM2 levels in patients have been suggested as a diagnostic marker for many types of cancers. However, it is not known how PKM2 is released in the blood, and whether the circulating PKM2 has any physiological function(s) in tumor progression. In this report, we demonstrate that PKM2 in the blood facilitates tumor growth by promoting tumor angiogenesis. Our experiments show that PKM2 promotes tumor angiogenesis by increasing endothelial cell proliferation, migration, and cell-ECM adhesion. Only the dimeric PKM2 possess the activity in promoting tumor angiogenesis, which is consistent with the observations that PKM2 in circulation of cancer patients is a dimer form.

To explore the clinical manifestations, antimicrobial therapy, and risk factors of mortality in patients with Acinetobacter baumannii bloodstream infection.Clinical data of 153 patients with Acinetobacter baumannii bloodstream infection hospitalized in First Affiliated Hospital of Zhejiang University from January 2013 to September 2014 were analyzed retrospectively.According to the 28-day survival after diagnosis, the patients were divided into death group (n=76) and survival group (n=77). Data related to demographic and clinical characteristics, underlying diseases, treatment, invasive procedures, bacterial resistance to antibiotics, acute physiology and chronic health evaluation Ⅱ(APACHEⅡ )scores at onset, and antimicrobial therapy were collected.The index as an independent risk factor of mortality was demonstrated by multivariate logistic regression analysis.This study included 153 patients with Acinetobacter baumannii bloodstream infection. The 28-day mortality was 49.7%. The independent risk factors of mortality were APACHE Ⅱ score ≥ 22 at onset (OR=15.7, 95%CI 5.1-48.1, P0.001), septic shock(OR=6.3, 95%CI 1.9-21.3, P=0.003), and administration of steroids(OR=3.6, 95%CI 1.0-12.3, P=0.043). Compared with subjects treated with non-cefoperazone-sulbactam-based regimen , those treated with cefoperazone-sulbactam for multidrug-resistant Acinetobacter baumannii(MDR-AB) had significantly lower mortality on day7, day14 and day28(8.9% vs 59.2%, 31.1% vs 65.8%, 44.4% vs 72.4% respectively).The patients with Acinetobacter baumannii bloodstream infection have high mortality within one month. Administration of steroids and septic shock are associated with poor prognosis. APACHEⅡ score ≥ 22 at onset predicts adverse outcome. Cefoperazone-sulbactam-based antimicrobial therapy improves patients' survival.

1-(3,5-Dimethoxyphenyl)-4-[(6-fluoro-2-methoxyquinoxalin-3-yl)aminocarbonyl] piperazine (RX-5902) exhibits strong growth inhibition in various human cancer cell lines with IC50 values ranging between 10 and 20 nM. In this study, we demonstrate that p68 RNA helicase is a cellular target of RX-5902 by the drug affinity responsive target stability (DARTS) method, and confirmed the direct binding of (3) H-labeled RX-5902 to Y593 phospho-p68 RNA helicase. We further demonstrated RX-5902 inhibited the β-catenin dependent ATPase activity of p68 RNA helicase in an in vitro system. Furthermore, we showed that treatment of cancer cells with RX-5902 resulted in the downregulation of the expression of certain genes, which are known to be regulated by the β-catenin pathway, such as c-Myc, cyclin D1 and p-c-Jun. Therefore, our study indicates that the inhibition of Y593 phospho-p68 helicase - β-catenin interaction by direct binding of RX-5902 to Y593 phospho-p68 RNA helicase may contribute to the anti-cancer activity of this compound.