Draft Genome Sequence of the Iron-Oxidizing, Acidophilic, and Halotolerant “Thiobacillus prosperus” Type Strain DSM 5130

“Thiobacillus prosperus” is a halotolerant mesophilic acidophile that gains energy through iron and sulfur oxidation. Its physiology is poorly understood. Here, we describe the principal genomic features of the type strain of T. prosperus, DSM 5130. This is the first public genome sequence of an acidophilic halotolerant bacterium

High temporal stability of supercurrents in MgB(2) materials

Fine grained polycrystalline samples of MgB(2) superconductor were synthesized from the elements to contain < 5 % of impurity phases, according to X-ray powder diffractometry. The superconductive transition was sharp with a midpoint Tc = 38.5 K. The magnetization in the vortex state was studied as a function of applied field H, temperature T, and time t. From the equilibrium magnetization, the London penetration depth was obtained. The supercurrent density J(T,H,t) in the vortex state (derived from the irreversible magnetization) decreases approximately linearly with T, in contrast to the quasi-exponential falloff in high-Tc superconductors. The current is highly stable in time, with normalized decay rates S = -d ln(J)/d ln(t) well below those in high-Tc materials. These results are compared with those of other superconductors.Comment: PDF file containing text and 6 figures, 12 pages tota

Effect of neutron irradiation on the London penetration depth for polycrystalline Bi(1.8)Pb(0.3)Sr2Ca2Cu3O10 superconductor

Magnetization studies of polycrystalline Bi(1.8)Pb(0.3)Sr2Ca2Cu3O10 superconductor, prior to and after neutron irradiation, showed an increase in J(sub c) due to irradiation damage. Analysis of the equilibrium magnetization revealed significant increases in other more fundamental properties. In particular, the London penetration depth increased by approximately 15 percent following irradiation with 8 x 10(exp 16) neutrons/sq cm. Corresponding changes were observed in the upper critical magnetic field H(sub c2). However, the most fundamental thermodynamic property, the superconductive condensation energy F(sub c), was unaffected by the moderate level of neutron-induced damage

Ergodic versus nonergodic behavior in oxygen deficient high-T_c superconductors

The oxygen defects induced phase transition from nonergodic to ergodic state in superconductors with intragrain granularity is considered within the superconductive glass model. The model predictions are found to be in a qualitative agreement with some experimental observations in deoxygenated high-T_c single crystals

Higher harmonics of ac voltage response in narrow strips of YBa2Cu3O7 thin films: Evidence for strong thermal fluctuations

We report on measurements of higher harmonics of the ac voltage response in strips of YBa2Cu3O7 thin films as a function of temperature, frequency and ac current amplitude. The third (fifth) harmonic of the local voltage is found to exhibit a negative (positive) peak at the superconducting transition temperature and their amplitudes are closely related to the slope (derivative) of the first (Ohmic) harmonic. The peaks practically do not depend on frequency and no even (second or fourth) harmonics are detected. The observed data can be interpreted in terms of ac current induced thermal modulation of the sample temperature added to strong thermally activated fluctuations in the transition region.Comment: 9 pages, 4 figures (PDF file

A Non-Gas-Based Cryotherapy System for the Treatment of Cervical Intraepithelial Neoplasia: A Mixed-Methods Approach for Initial Development and Testing.

BACKGROUND: Gas-based cryotherapy is the most widely used treatment strategy for cervical intraepithelial neoplasia (CIN) in low-resource settings, but reliance on gas presents challenges in low- and middle-income countries (LMICs). Our team adapted the original CryoPen Cryosurgical System, a cryotherapy device that does not require compressed gas and is powered by electricity, for use in LMICs. METHODS: A mixed-methods approach was used involving both qualitative and quantitative methods. First, we used a user-centered design approach to identify priority features of the adapted device. U.S.-based and global potential users of the adapted CryoPen participated in discussion groups and a card sorting activity to rank 7 features of the adapted CryoPen: cost, durability, efficacy and safety, maintenance, no need for electricity, patient throughput, and portability. Mean and median rankings, overall rankings, and summary rankings by discussion group were generated. In addition, results of several quantitative tests were analyzed including bench testing to determine tip temperature and heat extraction capabilities; a pathology review of CIN grade 3 cases (N=107) to determine target depth of necrosis needed to achieve high efficacy; and a pilot study (N=5) investigating depth of necrosis achieved with the adapted device to assess efficacy. RESULTS: Discussion groups revealed 4 priority themes for device development in addition to the need to ensure high efficacy and safety and low cost: improved portability, durability, ease of use, and potential for cure. Adaptions to the original CryoPen system included a single-core, single-tip model; rugged carrying case; custom circuit to allow car battery charging; and sterilization by high-level disinfection. In bench testing, there were no significant differences in tip temperature or heat extraction capability between the adapted CryoPen and the standard cryotherapy device. In 80% of the cases in the pilot study, the adapted CryoPen achieved the target depth of necrosis 3.5 mm established in the pathology review. CONCLUSION: The LMIC-adapted CryoPen overcomes barriers to standard gas-based cryotherapy by eliminating dependency on gas, increasing portability, and ensuring consistent freeze temperatures. Further testing and evaluation of the adapted CryoPen will be pursued to assess scalability and potential impact of this device in decreasing the cervical cancer burden in LMICs