Ultrastrong and ductile steel welds achieved by fine interlocking microstructures with film-like retained austenite.

The degradation of mechanical properties caused by grain coarsening or the formation of brittle phases during welding reduces the longevity of products. Here, we report advances in the weld quality of ultra-high strength steels by utilizing Nb and Cr instead of Ni. Sole addition of Cr, as an alternative to Ni, has limitations in developing fine weld microstructure, while it is revealed that the coupling effects of Nb and Cr additions make a finer interlocking weld microstructures with a higher fraction of retained austenite due to the decrease in austenite to acicular ferrite and bainite transformation temperature and carbon activity. As a result, an alloying design with Nb and Cr creates ultrastrong and ductile steel welds with enhanced tensile properties, impact toughness, and fatigue strength, at 45% lower material costs and lower environmental impact by removing Ni.

Fe-Al-Mn-C lightweight structural alloys: a review on the microstructures and mechanical properties.

Adding a large amount of light elements such as aluminum to steels is not a new concept recalling that several Fe-Al-Mn-C alloys were patented in 1950s for replacement of nickel or chromium in corrosion resistance steels. However, the so-called lightweight steels or low-density steels were revisited recently, which is driven by demands from the industry where steel has served as a major structural material. Strengthening without loss of ductility has been a triumph in steel research, but lowering the density of steel by mixing with light elements will be another prospect that may support the competitiveness against emerging alternatives such as magnesium alloys. In this paper, we review recent studies on lightweight steels, emphasizing the concept of alloy design for microstructures and mechanical properties. The influence of alloying elements on the phase constituents, mechanical properties and the change of density is critically reviewed. Deformation mechanisms of various lightweight steels are discussed as well. This paper provides a reason why the success of lightweight steels is strongly dependent on scientific achievements even though alloy development is closely related to industrial applications. Finally, we summarize some of the main directions for future investigations necessary for vitalizing this field of interest.

A new class of lightweight, stainless steels with ultra-high strength and large ductility.

Steel is the global backbone material of industrialized societies, with more than 1.8 billion tons produced per year. However, steel-containing structures decay due to corrosion, destroying annually 3.4% (2.5 trillion US$) of the global gross domestic product. Besides this huge loss in value, a solution to the corrosion problem at minimum environmental impact would also leverage enhanced product longevity, providing an immense contribution to sustainability. Here, we report a leap forward toward this aim through the development of a new family of low-density stainless steels with ultra-high strength (> 1 GPa) and high ductility (> 35%). The alloys are based on the Fe-(20-30)Mn-(11.5-12.0)Al-1.5C-5Cr (wt%) system and are strengthened by dispersions of nano-sized Fe3AlC-type κ-carbide. The alloying with Cr enhances the ductility without sacrificing strength, by suppressing the precipitation of κ-carbide and thus stabilizing the austenite matrix. The formation of a protective Al-rich oxide film on the surface lends the alloys outstanding resistance to pitting corrosion similar to ferritic stainless steels. The new alloy class has thus the potential to replace commercial stainless steels as it has much higher strength at similar formability, 17% lower mass density and lower environmental impact, qualifying it for demanding lightweight, corrosion resistant, high-strength structural parts.

Positive-thinking and life satisfaction amongst Koreans.

PURPOSE: The present study examined the positive-thinking and life satisfaction of the general Korean population. In particular, we examined the role of positive-thinking on participants' life satisfaction. MATERIALS AND METHODS: We conducted a telephone survey of 409 respondents (194 males, 215 females). The participants provided self-reports on their positive thinking, life satisfaction and demographic information. RESULTS: The results showed that age, education, occupation, and family income had an influence on positive- thinking as well as life satisfaction in Korea. Specifically, younger respondents and persons with high incomes or higher education degrees were more likely to have higher positive scores and thus higher life satisfaction scores. However, after controlling for the demographic variables, positive thinking significantly affected life satisfaction(R(2) Change=0.170, F= 88.56, p < 0.001). CONCLUSION: We provided empirical evidence that positive thinking may indeed play a significant role in life satisfaction. Therefore, positive thinking would offer important direction for the growth of life satisfaction and interventions aiming to remediate the effects of demographic variables on life satisfaction.

Simvastatin/Ezetimibe Therapy for Recalcitrant Alopecia Areata: An Open Prospective Study of 14 Patients.

BACKGROUND: Simvastatin belongs to the statin family, whose members have immunomodulatory activities. Ezetimibe have synergetic effects when co-administered with simvastatin. In several case reports, alopecia totalis and alopecia universalis were successfully treated with simvastatin/ezetimibe, suggesting that this combination could be a new efficient therapy for recalcitrant alopecia areata (AA). OBJECTIVE: To verify the efficacy of the simvastatin/ezetimibe combination therapy for recalcitrant AA and investigate the relationship between various treatment responses and prognostic factors. METHODS: This prospective open study was performed in patients with recalcitrant AA with the bald surface exceeding 75%. All patients took simvastatin (40 mg) and ezetimibe (10 mg) daily. The extent of hair regrowth expressed as percentage of the bald area was used to evaluate the effectiveness of the therapy. RESULTS: Of 14 enrolled patients, 4 patients (28.6%) were judged as responders showing regrowth of 30% to 80% after 3 months of treatment. The mean age of onset in non-responders was significantly lower than in responders. The total score of prognostic factors, calculated as a sum of factors related to poor prognosis, was much lower in responders than in non-responders. CONCLUSION: The remission rate in this study was unsatisfactory. However, since the recruited patients had not responded to any other treatments for AA, simvastatin/ezetimibe can still be considered as an alternative treatment for recalcitrant AA. The total scores of the prognostic factors were statistically different between responders and non-responders. These results can be used to predict the outcome of treatment with simvastatin/ezetimibe and anticipate prognosis.

Syringoid Eccrine Carcinoma of the Thigh.

Syringoid eccrine carcinoma (SEC) is a rare cutaneous malignant tumor thought to be derived from eccrine sweat apparatus. It is usually present in the head, neck and trunk region, and often occurs in the fourth to seventh decades of life. A 94-year-old male patient visited our department with an 80-year history of a lesion showing a 2×2 cm sized well-demarcated round shaped erythematous to pinkish colored nodule with ulcer on his left thigh. Histological findings revealed a tumor consisted mainly of numerous small cords and nests forming luminal or tubular structures and tumor cells showing variable atypia. Some ductal structures showed tadpole appearance. On immunohistochemical staining, epithelial membrane antigen, S-100, cytokeratin 7 and carcinoembryonic antigen were reactive and Ki-67 showed less than 10% positivity. Based on these findings, the final diagnosis was made as SEC. The patient was treated with local wide excision and didn't show any recurrence during the follow-up period of 12 months. Herein, we report a very rare case of SEC which occurred on the left thigh and discuss 10 cases of SEC presented on the extremities, including our case.

Investigations of the efficacy of diphenylcyclopropenone immunotherapy for the treatment of warts.

BACKGROUND: Diphenylcyclopropenone (DPCP) immunotherapy has been used to treat warts, particularly in patients, such as children, who cannot endure treatment-related pain and in patients with large numbers of warts. However, the efficacy of DPCP immunotherapy remains subject to much controversy. Specifically, cure rates and treatment durations have varied across reports, primarily because of the lack of large-scale studies. METHODS: We performed an uncontrolled, open-label study to investigate the efficacy of DPCP immunotherapy for the treatment of cutaneous warts. A total of 170 patients with warts were enrolled in this uncontrolled, open-label study from 2006 to 2012. Each patient was sensitized with 0.1% DPCP. Two weeks after sensitization, DPCP was applied to warts once per week. RESULTS: We achieved high clearance rates in 141 of 170 patients (82.9%) and 434 of 511 lesions (84.9%). Immunotherapy with DPCP was much more effective when the lesions were located on the hands and when the patient was aged < 20 years. The mean ± standard deviation number of applications was 9.02 ± 2.59. At the end of treatment, the most common final concentration was 0.1%, and most (77.0%) patients used a final concentration of > 0.005%. Side effects occurred in 36 patients, but no serious adverse effects occurred, and blistering at the sensitized site was the most common adverse effect. CONCLUSIONS: Immunotherapy with DPCP is an effective and well-tolerated option for the treatment of recalcitrant warts.

Association between TLR1 polymorphisms and alopecia areata.

Toll-like receptors (TLRs) may contribute to the process of autoimmune attacks on hair follicles. To investigate whether the TLR1 gene polymorphisms are associated with the development and clinical features of alopecia areata (AA), a case-control comparison of two single nucleotide polymorphisms (SNPs) (rs4833095, Asn248Ser and rs5743557, -414C > T) of TLR1 were studied in 239 AA patients and 248 controls. Using multiple logistic regression model, odds ratios, 95% confidence intervals and corresponding p values were estimated. Clinical features were analyzed based on the age of onset, family history, type of AA, nail involvement and body hair involvement. The missense SNP rs4833095 was significantly associated with the development of AA (codominant2, p = 0.002; recessive, p = 0.001; log-additive, p = 0.0071; and allele frequency, p = 0.0066). The promoter SNP rs5743557 was weakly associated with the development of AA (codominant2, p = 0.019; recessive, p = 0.032; log-additive, p = 0.020; and allele frequency, p = 0.03). In the clinical features, rs4833095 was only weakly associated with age of onset between 15 and 50 years (codominant2, p = 0.043 and recessive, p = 0.022). The results suggest that rs4833095 of TLR1 may be associated with the susceptibility for AA in the Korean population.

Analysis of transformation plasticity in steel using a finite element method coupled with a phase field model.

An implicit finite element model was developed to analyze the deformation behavior of low carbon steel during phase transformation. The finite element model was coupled hierarchically with a phase field model that could simulate the kinetics and micro-structural evolution during the austenite-to-ferrite transformation of low carbon steel. Thermo-elastic-plastic constitutive equations for each phase were adopted to confirm the transformation plasticity due to the weaker phase yielding that was proposed by Greenwood and Johnson. From the simulations under various possible plastic properties of each phase, a more quantitative understanding of the origin of transformation plasticity was attempted by a comparison with the experimental observation.