Real-time observations of TRIP-induced ultrahigh strain hardening in a dual-phase CrMnFeCoNi high-entropy alloy.

Strategies involving metastable phases have been the basis of the design of numerous alloys, yet research on metastable high-entropy alloys is still in its infancy. In dual-phase high-entropy alloys, the combination of local chemical environments and loading-induced crystal structure changes suggests a relationship between deformation mechanisms and chemical atomic distribution, which we examine in here in a Cantor-like Cr20Mn6Fe34Co34Ni6 alloy, comprising both face-centered cubic (fcc) and hexagonal closed packed (hcp) phases. We observe that partial dislocation activities result in stable three-dimensional stacking-fault networks. Additionally, the fraction of the stronger hcp phase progressively increases during plastic deformation by forming at the stacking-fault network boundaries in the fcc phase, serving as the major source of strain hardening. In this context, variations in local chemical composition promote a high density of Lomer-Cottrell locks, which facilitate the construction of the stacking-fault networks to provide nucleation sites for the hcp phase transformation

Accelerated Ulcer Healing and Resistance to Ulcer Recurrence with Gastroprotectants in Rat Model of Acetic Acid-induced Gastric Ulcer

Quality of ulcer healing (QOUH) is defined as ideal ulcer healing featuring with the fine granular ulcer scar, high functional restoration and the resistance to recurrence. This study was designed to compare the rates of QOUH achievement in rat gastric ulcer model between acid suppressant treated group and gastroprotectant treated group accompanied with elucidations of molecular mechanisms. Serosal injection of acetic acids for generating gastric ulcer and intraperitoneal (ip) injection of recombinant interleukin 1-beta (IL-1β) for recurring healed ulcer was done in SD rats. The 72 rats were divided into three groups according to treatment as follows; Group I, no further treatment, Group II, 8 weeks treatment of omeprazole, and Group III, 8 weeks of gastroprotectant treatment. IL-1β was administered for ulcer recurrence after 28 weeks of acetic acid injection. At four weeks after gastric ulcerogenesis, 58.3% (7/12) of active gastric ulcer were converted to healing stage in Group III, but 16.7% (2/12) in Group II and none in Group I, for which significant levels of epidermal growth factor, mucin, and pS2/trefoil peptide1 were contributive to these accelerated healings of Group III. ip injections of rIL-1β (200 µg/kg) at 28 weeks after acetic acid injection led to 100% of ulcer recurrence in Group I and 75.0% in Group II, but only 16.7% of Group III rats showed ulcer recurrence. Significantly attenuated levels of inflammatory cytokines including IL-2, transforming growth factor-alpha (TNF-α), cyclooxygenase-2 (COX-2), nitrotyrosine were responsible for the resistance to ulcer recurrence in Group III. Conclusively, gastroprotectant might be prerequisite in order to achieve ideal QOUH through significant inductions of remodeling

Surgical castration efficiently delays the time of starting a systemic chemotherapy in castration-resistant prostate cancer patients refractory to initial androgen-deprivation therapy

AbstractBackgroundThe aim of this study was to investigate the effects of surgical castration, particularly delaying the time to entrance of systemic chemotherapy, in castration-resistant prostate cancer (CRPC) patients who were refractory to initial combination androgen deprivation therapy.Materials and methodsWe analyzed the clinical data of 14 CRPC patients diagnosed at Seoul National University Bundang Hospital (SNUBH) from November 2008 through May 2015. After exclusion of three patients, we finally analyzed the baseline characteristics of 11 CRPC patients. We also assessed the delaying time of docetaxel administration, which was defined as response duration, after surgical castration.ResultsAfter bilateral orchiectomy, the treatment response rate was 45.4% and the median duration of response was 9 months (range 4–48 mo). Responders had less aggressive biopsy Gleason scores compared to nonresponders. Notably, responders showed the reducing pattern of serum prostate specific antigen levels, while nonresponders demonstrated increasing tendency after surgical castration. Moreover, responders also presented with a reduction pattern of serum testosterone levels, whereas nonresponders showed an increasing pattern of testosterone levels after bilateral orchiectomy.ConclusionsIn summary, despite the limited number of cases for convincing evidence, our results shed light again on the clinical benefits of surgical castration prior to the systemic chemotherapy in some CRPC patients after initial hormone therapy

A first-order differential double subordination with applications

Let $q_1$ and $q_2$ belong to a certain class of normalized analytic univalent functions in the open unit disk of the complex plane. Sufficient conditions are obtained for normalized analytic functions $p$ to satisfy the double subordination chain $q_1(z)\prec p(z)\prec q_2(z)$. The differential sandwich-type result obtained is applied to normalized univalent functions and to $\Phi$-like functions

Effects on Growth and Osteogenic Differentiation of Mesenchymal Stem Cells by the Zinc-Added Sol-Gel Bioactive Glass Granules

Responses of mesenchymal stem cells (MSCs) cultured with zinc-added (2 and 5%) bioactive glass granules were evaluated in terms of cell growth and osteogenic differentiation. MSCs were cultured with different quantities (3, 10 and 30) of glass granules for up to 21 days in the osteogenic medium. Cell growth was stimulated by a small quantity of glasses, particularly those that contained zinc. Osteogenic differentiation, as assessed by alkaline phosphatase activity (ALP) activity, was significantly enhanced by the glasses, particularly with large quantities of glass and for prolonged culturing. Expression of bone-sialo protein (BSP) was significantly up-regulated around the bioactive glass granules. Moreover, the zinc addition significantly altered the ALP and BSP depending on the culture time and glass quantity. Cellular mineralization was improved in all glass samples, and particularly in the 2% zinc-glass. Taken together, the zinc addition to bioactive glass induced the MSCs growth and their osteogenic differentiation, at least to the level of zinc-free glass, and with even higher level observed depending on the quantity and culture time. These findings indicate that the zinc addition to bioactive glass may be useful in development of biomaterials for the stimulation of adult stem cell in bone tissue engineering

Duplexer using microwave photonic band gap structure

We propose a frequency selective duplexer using microwave photonic band gap (PBG) structures. It uses two different PBGs to control the propagation of electromagnetic waves in the microwave region. In this structure, an additional narrow reflection band appears in the transmission spectrum when the PBG structure is not properly located relative to the T junction. By considering multiple reflections, it is proved that this additional reflection band in each PBG structure results from the interference between the input wave and the reflected wave from the other PBG structure. An effective way to prevent this interference effect is also discussed