The phase diagram of high-Tc's: Influence of anisotropy and disorder

We propose a phase diagram for the vortex structure of high temperature superconductors which incorporates the effects of anisotropy and disorder. It is based on numerical simulations using the three-dimensional Josephson junction array model. We support the results with an estimation of the internal energy and configurational entropy of the system. Our results give a unified picture of the behavior of the vortex lattice, covering from the very anysotropic BiSrCaCuO to the less anisotropic YBaCuO, and from the first order melting ocurring in clean samples to the continuous transitions observed in samples with defects.Comment: 8 pages with 7 figure

Teleoncology in the Department of Defense: A tale of two systems

ABSTRACT Two telemedicine networks were developed for the purpose of conducting multidisciplinary oncology ("teleoncology") conferences. The infrastructure of each system differed: one system was Internet-based; the other was delivered via Integrated Services Digital Network (ISDN) lines. The purpose of this study was to describe the infrastructure and cost, consultative process, technical aspects, and conference format of the two teleoncology programs. The two systems' technical aspects, participant satisfaction with the systems, and conference participation were compared qualitatively. Assessment of the technical aspects of the systems suggested that each had distinct advantages. Survey results indicated that provider satisfaction with the technical and logistical aspects of each type of teleoncology conference was high. The present study may prove helpful for individuals who are considering implementing their own teleoncology programs. T ELEM ED ICIN E H A S BEEN D ESCRIBED as the practice of medicine at a distance. 1 Telemedicine applications have been used in nearly every field of medicine, including radiology, psychiatry, dermatology, and cardiology. One aspect of telemedicine that has become increasingly common is teleoncology, the delivery of oncology services from a distance. 1 Teleoncology programs offer a variety of potential benefits, including enhancing primary care managers' access to referrals, expand opportunities for continuing medical education (CME) credits, reduction of unnecessary referrals, and smooth coordination of patient care. To date, only a handful of studies have examined the topic of teleoncology. Investigators have looked at the use of interactive video to provide psychosocial support, 2 the use of interactive video and proxy examiners to provide direct patient care, 3 and the use of teleoncology to facilitate consultation by cancer specialists to geographically remote primary care providers

Thermal Conversion of Guanylurea Dicyanamide into Graphitic Carbon Nitride via Prototype CNx Precursors

Guanylurea dicyanamide, [(H2N)C(-O)NHC(NH2)2][N(CN)2], has been synthesized by ion exchange reaction in aqueous solution and structurally characterized by single-crystal X-ray diffraction (C2/c, a = 2249.0(5) pm, b = 483.9(1) pm, c = 1382.4(3) pm, β = 99.49(3)°, V = 1483.8(5) × 106 pm3, T = 130 K). The thermal behavior of the molecular salt has been studied by thermal analysis, temperature-programmed X-ray powder diffraction, FTIR spectroscopy, and mass spectrometry between room temperature and 823 K. The results were interpreted on a molecular level in terms of a sequence of thermally induced addition, cyclization, and elimination reactions. As a consequence, melamine (2,4,6-triamino-1,3,5-triazine) is formed with concomitant loss of HNCO. Further condensation of melamine yields the prototypic CNx precursor melem (2,6,10-triamino-s-heptazine, C6N7(NH2)3), which alongside varying amounts of directly formed CNxHy material transforms into layered CNxHy phases without significant integration of oxygen into the core framework owing to the evaporation of HNCO. Thus, further evidence can be added to melamine and its condensation product melem acting as “key intermediates” in the synthetic pathway toward graphitic CNxHy materials, whose exact constitution is still a point at issue. Due to the characteristic formation process and hydrogen content a close relationship with the polymer melon is evident. In particular, the thermal transformation of guanylurea dicyanamide clearly demonstrates that the formation of volatile compounds such as HNCO during thermal decomposition may render a large variety of previously not considered molecular compounds suitable CNx precursors despite the presence of oxygen in the starting material

Treatment of Cryptococcal Meningitis with Combination Amphotericin B and Flucytosine for Four as Compared with Six Weeks

Abstract One hundred ninety-four patients with cryptococcal meningitis were enrolled in a multicenter, prospective, randomized clinical trial to compare the efficacy and toxicity of four as compared with six weeks of combination amphotericin B and flucytosine therapy. Among 91 patients who met preestablished criteria for randomization, cure or improvement was noted in 75 percent of those treated for four weeks and in 85 percent of those treated for six weeks. The estimated relapse rate for the four-week regimen was higher — 27 as compared with 16 percent — whereas the incidence of toxic effects for the two regimens was similar — 44 as compared with 43 percent. Among 23 transplant recipients, 4 of 5 treated for four weeks relapsed, leading to the decision to treat the rest of the group for six weeks. Only 3 of the 18 treated for six weeks relapsed. In a third group of 80 patients, the protocol was not followed during the initial four weeks, and these patients were not randomized. Thirty-eight died or relapsed. Multifactorial analysis of pretreatment factors for all 194 patients identified three significant predictors (P These and other findings in this study are consistent with the view that the four-week regimen should be reserved for patients who have meningitis without neurologic complications, underlying disease, or immunosuppressive therapy; a pretreatment cerebrospinal fluid white-cell count above 20 per cubic millimeter and a serum cryptococcal antigen titer below 1:32; and at four weeks of therapy, a negative cerebrospinal fluid India ink preparation and serum and cerebrospinal fluid cryptococcal-antigen titers below 1:8. Patients who do not meet these criteria should receive at least six weeks of therapy. (N Engl J Med 1987; 317:334–41.

10-Year Outcomes after Monitoring, Surgery, or Radiotherapy for Localized Prostate Cancer

BACKGROUND The comparative effectiveness of treatments for prostate cancer that is detected by prostatespecific antigen (PSA) testing remains uncertain. METHODS We compared active monitoring, radical prostatectomy, and external-beam radiotherapy for the treatment of clinically localized prostate cancer. Between 1999 and 2009, a total of 82,429 men 50 to 69 years of age received a PSA test; 2664 received a diagnosis of localized prostate cancer, and 1643 agreed to undergo randomization to active monitoring (545 men), surgery (553), or radiotherapy (545). The primary outcome was prostate-cancer mortality at a median of 10 years of follow-up. Secondary outcomes included the rates of disease progression, metastases, and all-cause deaths. RESULTS There were 17 prostate-cancer-specific deaths overall: 8 in the active-monitoring group (1.5 deaths per 1000 person-years; 95% confidence interval [CI], 0.7 to 3.0), 5 in the surgery group (0.9 per 1000 person-years; 95% CI, 0.4 to 2.2), and 4 in the radiotherapy group (0.7 per 1000 person-years; 95% CI, 0.3 to 2.0); the difference among the groups was not significant (P = 0.48 for the overall comparison). In addition, no significant difference was seen among the groups in the number of deaths from any cause (169 deaths overall; P = 0.87 for the comparison among the three groups). Metastases developed in more men in the active-monitoring group (33 men; 6.3 events per 1000 person-years; 95% CI, 4.5 to 8.8) than in the surgery group (13 men; 2.4 per 1000 person-years; 95% CI, 1.4 to 4.2) or the radiotherapy group (16 men; 3.0 per 1000 person-years; 95% CI, 1.9 to 4.9) (P = 0.004 for the overall comparison). Higher rates of disease progression were seen in the active-monitoring group (112 men; 22.9 events per 1000 person-years; 95% CI, 19.0 to 27.5) than in the surgery group (46 men; 8.9 events per 1000 person-years; 95% CI, 6.7 to 11.9) or the radiotherapy group (46 men; 9.0 events per 1000 person-years; 95% CI, 6.7 to 12.0) (P<0.001 for the overall comparison). CONCLUSIONS At a median of 10 years, prostate-cancer-specific mortality was low irrespective of the treatment assigned, with no significant difference among treatments. Surgery and radiotherapy were associated with lower incidences of disease progression and metastases than was active monitoring. (Funded by the National Institute for Health Research; ProtecT Current Controlled Trials number, ISRCTN20141297; ClinicalTrials.gov number, NCT02044172.) a bs tr ac

Total Intravenous Anesthesia Including Ketamine versus Volatile Gas Anesthesia for Combat-related Operative Traumatic Brain Injury

Background: Traumatic brain injury is a leading cause of death and severe neurologic disability. The effect of anesthesia techniques on neurologic outcomes in traumatic brain injury and potential benefits of total intravenous anesthesia (TIVA) compared with volatile gas anesthesia (VGA), although proposed, has not been well evaluated. The purpose of this study was to compare TIVA versus VGA in patients with combatrelated traumatic brain injury. Methods: The authors retrospectively reviewed 252 patients who had traumatic brain injury and underwent operative neurosurgical intervention. Statistical analyses, including propensity score and matched analyses, were performed to assess differences between treatment groups (TIVA vs. VGA) and good neurologic outcome. Results: Two hundred fourteen patients met inclusion criteria and were analyzed; 120 received VGA and 94 received TIVA. Good neurologic outcome (Glasgow Outcome Score 4 -5) and decreased mortality were associated with TIVA compared with VGA (75% vs. 54%; P ‫؍‬ 0.002 and 5% vs. 16%; P ‫؍‬ 0.02, respectively). Multivariate logistic regression found admission Glasgow Coma Scale score of 8 or greater (odds ratio, 13.3; P < 0.001) and TIVA use (odds ratio, 2.3; P ‫؍‬ 0.05) to be associated with good neurologic outcomes. After controlling for confounding factors using propensity analysis and repeated one-to-one matching of patients receiving TIVA with those receiving VGA with regard to Injury Severity Score, Glasgow Coma Scale score, base deficit, Head Abbreviated Injury Score, and craniectomy or craniotomy, the authors could not find an association between treatment and neurologic outcome. Conclusion: Total intravenous anesthesia often including ketamine was not associated with improved neurologic outcom