Microstructure control in Sn-0.7mass%Cu alloys

Soldering alloys based oft the Sn-Cu alloy system are amongst the most favourable lead-free alternatives due to a range of attractive properties. Trace additions of Ni have been found to significantly improve the soldering characteristics of these alloys (reduced bridging etc.). This paper examines the mechanisms underlying the improvement in soldering properties of Sn-0.7 mass%Cu eutectic alloys modified with concentrations of Ni ranging front 0 to 1000 ppm. The alloys were investigated by thermal analysis during solidification, as well as optical/SEM microanalyses of fully solidified samples anti samples quenched during solidification. It is concluded that Ni additions dramatically alter the nucleation patterns and solidification behaviour of the Sn-Cu6Sn5 eutectic anti that these changes are related to the superior soldering characteristics of the Ni-modified Sn-0.7 mass%Cu alloys

Adenomyoepithelioma of the Breast A with an Immunohistochemical Study

Adenomyoepithelioma is a rare primary tumor of the breast in women. It is characterized by a bicellular pattern consisting of both ductal and myoepithelial elements. We report here an additional case of adenomyoepithelioma in a 57-year-old woman. The aspiration cytology revealed atypical cell clusters, and the simple mastectomy was performed under the diagnosis of ductal carcinoma. Macroscopically, the tumor presented as a well-defined mass. Histologically, the tumor demonstrated the characteristic bicellular growth pattern consisting of ducts and a periductal proliferation of mainly polygonal neoplastic cells. Immunohistochemically, epithelial cells lining the glandular structures were strongly positive for cytokeratin and epithelial membrane antigen (EMA). Polygonal myoepithelial cells gave negative reactions with cytokeratin and EMA. Most polygonal myoepithelial cells were positive for ﾎｱ-smooth muscle actin (SMA) and S-100 protein. Our case was a representative example of a typical adenomyoepithelioma, but the cytological diagnosis needs a deep attention to avoid overdiagnosis

Telephone triage service use is associated with better outcomes among patients with cerebrovascular diseases: a propensity score analysis using population-based data

IntroductionThe telephone triage service is an emergency medical system through which citizens consult telephone triage nurses regarding illness, and the nurses determine the urgency and need for an ambulance. Despite being introduced in several countries, its impact on emergency patients has not been reported. We aimed to determine the effect of the telephone triage service on the outcomes of hospitalized patients diagnosed with cerebrovascular disease upon arrival after being transported by an ambulance.MethodsThis retrospective study included patients with cerebrovascular disease who were transported by ambulance between January 2016 and December 2019. The primary outcome was discharge to home by day 21 of hospitalization. A total of 344 patients who used the telephone triage service were propensity score-matched to 344 patients who directly called for an ambulance.ResultsTelephone triage service use was associated with discharge to home by hospital day 21 (crude odd ratio: 1.8; 95% confidence interval: 1.3–2.4) and was not significantly associated with survival on hospital day 21 in multivariate regression analysis.ConclusionThe prognoses of cerebral infarction, intracerebral hemorrhage, and subarachnoid hemorrhage depend on the time from symptom onset to treatment. Telephone triage services may allow patients to receive treatment more rapidly than traditional ambulance requests, resulting in improved patient outcomes. The findings of this study suggest that the use of telephone triage services is associated with improved outcomes in patients with cerebrovascular disease and indicate that the costs for medical expenses and disability may be greatly reduced in an aging society

Cysteinyl-tRNA synthetase governs cysteine polysulfidation and mitochondrial bioenergetics

Cysteine hydropersulfide (CysSSH) occurs in abundant quantities in various organisms, yet little is known about its biosynthesis and physiological functions. Extensive persulfide formation is apparent in cysteine-containing proteins in Escherichia coli and mammalian cells and is believed to result from post-translational processes involving hydrogen sulfide-related chemistry. Here we demonstrate effective CysSSH synthesis from the substrate l-cysteine, a reaction catalyzed by prokaryotic and mammalian cysteinyl-tRNA synthetases (CARSs). Targeted disruption of the genes encoding mitochondrial CARSs in mice and human cells shows that CARSs have a crucial role in endogenous CysSSH production and suggests that these enzymes serve as the principal cysteine persulfide synthases in vivo. CARSs also catalyze co-translational cysteine polysulfidation and are involved in the regulation of mitochondrial biogenesis and bioenergetics. Investigating CARS-dependent persulfide production may thus clarify aberrant redox signaling in physiological and pathophysiological conditions, and suggest therapeutic targets based on oxidative stress and mitochondrial dysfunction

High-Resolution Submillimeter and Near-Infrared Studies of the Transition Disk around Sz 91

To reveal the structures of a transition disk around a young stellar object in Lupus, Sz 91, we have performed aperture synthesis 345 GHz continuum and CO(3--2) observations with the Submillimeter Array (\sim1\arcsec--3\arcsec resolution), and high-resolution imaging of polarized intensity at the $K_s$-band by using the HiCIAO instrument on the Subaru Telescope (0\farcs25 resolution). Our observations successfully resolved the inner and outer radii of the dust disk to be 65 AU and 170 AU, respectively, which indicates that Sz 91 is a transition disk source with one of the largest known inner holes. The model fitting analysis of the spectral energy distribution reveals an H$_2$ mass of $2.4\times10^{-3}$ M_\sun in the cold ($T<$30 K) outer part at $65<r<170$ AU by assuming a canonical gas-to-dust mass ratio of 100, although a small amount ($>3\times10^{-9}$ M_\sun) of hot ($T\sim$180 K) dust possibly remains inside the inner hole of the disk. The structure of the hot component could be interpreted as either an unresolved self-luminous companion body (not directly detected in our observations) or a narrow ring inside the inner hole. Significant CO(3--2) emission with a velocity gradient along the major axis of the dust disk is concentrated on the Sz 91 position, suggesting a rotating gas disk with a radius of 420 AU. The Sz 91 disk is possibly a rare disk in an evolutionary stage immediately after the formation of protoplanets because of the large inner hole and the lower disk mass than other transition disks studied thus far

Belediye Müzesi

Taha Toros Arşivi, Dosya No: 114-Müzelerİstanbul Kalkınma Ajansı (TR10/14/YEN/0033) İstanbul Development Agency (TR10/14/YEN/0033