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The work is devoted to the study of the dependence of the structure, magnetic properties, and functional properties such as shape memory effect (SME) and magneto caloric effect (MCE) of Heusler alloys of the Ni51 – xMn33.4In15.6Vx family on the degree of vanadium doping x. Studies using scanning electron microscope (SEM), differential scanning calorimetry (DSC) and magnetometry revealed in all studied samples of Heusler Ni51 – xMn33.4In15.6Vx alloys the presence of a Curie point type magnetic phase transition (PT) and a metamagnetostructural phase transition (MMSPT), of the first order which is accompanied by a sharp decrease in magnetization in the low-temperature martensitic phase. The temperature of the magnetic PT is weakly dependent on x, the temperature of the MMSPT decreases with increasing x. The temperature of the MMSPT is very sensitive to the magnetic field. For the Ni50Mn33.4In15.6V1 sample, the sensitivity is—5 K/T. Direct measurements of the MCE in alternating magnetic fields of 0.62 and 1.2 T showed the presence of a direct MCE at the point of magnetic PT and an inverse MCE at the point of MMSPT. There is a strong decrease in the MCE with an increase in the frequency of the alternating magnetic field from 1 to 30 Hz both near the magnetic PT and near the MMSPT. Measurements of the dependence of bending deformation on load and temperature have shown that all studied alloys exhibit SME near MMSPT. It can be concluded that due to the combination of high sensitivity of MMSPT to the field and SME, this family of alloys is promising for the creation of magnetically controlled actuators. [ABSTRACT FROM AUTHOR]

From the viewpoint of precision and reliability of radioisotopic dating, deposits whose quantitative age can be determined through several methods of geochronometry are of special interest. The mutually conforming finite C and Th/U dates of buried Neopleistocene organic deposits, taken from the Tolokonka section by the North Dvina River (100 km downstream from the city of Kotlas), have been obtained for the first time in Russia. The stratigraphical reference of these results to those obtained via the optically induced luminescence for upper and lower bedding layers has been established. The presented geochronometric data have allowed us to consider the age of oxbow lake organic deposits completely reliable and refer the time of their formation to the Tyrbei warming within the MIS-3. The applicability of the new version of the Th/U method for dating of interglacial and interstadial deposits, for the purpose of solving the Middle and Late Neopleistocene chronostratigraphy issues, is confirmed. [ABSTRACT FROM AUTHOR]

Objectives: To report a premarket multicenter trial to test the feasibility of a transvaginal silicone-coated polyester synthetic mesh sling in women with anatomic incontinence., Methods: Fifty-one patients in four centers underwent transvaginal placement of a silicone-coated polyester synthetic mesh sling (American Medical Systems) during an 8-month period. Of the 51 patients, 31 were part of a prospective institutional review board-approved feasibility trial in three centers funded by American Medical Systems (group 1) and 20 underwent implantation by a single surgeon and their data were retrospectively reviewed (group 2). The studies were done concomitantly, and all slings were fixed transvaginally with bone anchors. All patients in group 1 were followed up at 4 weeks, 6 months, and 1 year (as applicable) with repeat questionnaires, physical examinations, and pad tests., Results: In group 1, 20 patients completed 6 months of follow-up. Ten patients (32%) required a second surgical procedure at an average of 183 days (range 68 to 343) postoperatively. Eight patients (26%) had vaginal extrusion of the mesh, one (3%) required sling lysis, and one (3%) required sling removal because of infection. In group 2, 8 patients (40%) underwent sling removal for vaginal extrusion at a mean of 160 days (range 83 to 214)., Conclusions: Transvaginally placed silicone-coated mesh slings used for the treatment of urinary incontinence demonstrated an unacceptably high vaginal extrusion rate in this study. Once identified, this study was immediately terminated, and this product was not marketed for this application in the United States.

The propensity of patients with carcinoma in situ (CIS) of the bladder to progress to invasive and metastatic disease is clearly established. Today, the standard therapy in treating patients with CIS of the bladder is intravesical bacillus Calmette-Guerin (BCG). Nevertheless, patients who fail intravesical BCG have few viable options except to undergo a radical cystectomy. Valrubicin (N-trifluoroacetyladriamycin-14-valerate) is a new semisynthetic derivative of the anthracycline antibiotic doxorubicin that has been shown to benefit patients with BCG-refractory CIS of the bladder. Intravesical instillation of valrubicin is well-tolerated, safe and can be durable. Early non-randomised studies show promise and the current utilisation of this drug is limited to patients with BCG-refractory CIS of the bladder who are not good surgical candidates. Randomised studies of intravesical valrubicin for the treatment of superficial bladder cancer are ongoing.