Thermal pairing and giant dipole resonance in highly excited nuclei

Recent results are reported showing the effects of thermal pairing in highly excited nuclei. It is demonstrated that thermal pairing included in the phonon damping model (PDM) is responsible for the nearly constant width of the giant dipole resonance (GDR) at low temperature $T <$ 1 MeV. It is also shown that the enhancement observed in the recent experimentally extracted nuclear level densities in $^{104}$Pd at low excitation energy and various angular momenta is the first experimental evidence of the pairing reentrance in finite (hot rotating) nuclei. In the study of GDR in highly excited nuclei, the PDM has been extended to include finite angular momentum. The results of calculations within the PDM are found in excellent agreement with the latest experimental data of GDR in the compound nucleus $^{88}$Mo. Finally, an exact expression is derived to calculate the shear viscosity $\eta$ as a function of $T$ in finite nuclei directly from the GDR width and energy at zero and finite $T$. Based on this result, the values $\eta/s$ of specific shear viscosity in several medium and heavy nuclei were calculated and found to decrease with increasing $T$ to reach $(1.3 - 4)\times\hbar/(4\pi k_B)$ at $T =$ 5 MeV, that is almost the same value obtained for quark-gluon-plasma at $T >$ 170 MeV.Comment: 6 pages, 4 figures, invited lecture at the 11th Spring Seminar on Nuclear Physics, Ischia May 12 - 16, 201

Comparison of a new multiplex real-time PCR with the Kato Katz thick smear and copro-antigen ELISA for the detection and differentiation of Taenia spp. in human stools

Background : Taenia solium, the cause of neurocysticercosis (NCC), has significant socioeconomic impacts on communities in developing countries. This disease, along with taeniasis is estimated to infect 2.5 to 5 million people globally. Control of T. solium NCC necessitates accurate diagnosis and treatment of T. solium taeniasis carriers. In areas where all three species of Taenia tapeworms (T. solium, Taenia saginata and Taenia asiatica) occur sympatrically, conventional microscope-and copro-antigen based diagnostic methods are unable to distinguish between these three Taenia species. Molecular diagnostic tools have been developed to overcome this limitation; however, conventional PCR-based techniques remain unsuitable for large-scale deployment in community-based surveys. Moreover, a real-time PCR (qPCR) for the discrimination of all three species of Taenia in human stool does not exist. This study describes the development and validation of a new triplex Taq-Man probe-based qPCR for the detection and discrimination of all three Taenia human tapeworms in human stools collected from communities in the Central Highlands of Vietnam. The diagnostic characteristics of the test are compared with conventional Kato Katz (KK) thick smear and copro-antigen ELISA (cAgELISA) method utilizing fecal samples from a community based cross-sectional study. Using this new multiplex real-time PCR we provide an estimate of the true prevalence of taeniasis in the source population for the community based cross-sectional study. Methodology/Principal findings : Primers and TaqMan probes for the specific amplification of T. solium, T. saginata and T. asiatica were designed and successfully optimized to target the internal transcribed spacer I (ITS-1) gene of T. solium and the cytochrome oxidase subunit I (COX-1) gene of T. saginata and T. asiatica. The newly designed triplex qPCR (T3qPCR) was compared to KK and cAgELISA for the detection of Taenia eggs in stool samples collected from 342 individuals in Dak Lak province, Central Highlands of Vietnam. The overall apparent prevalence of taeniasis in Dak Lak province was 6.72% (95% confidence interval (CI) [3.94-9.50]) in which T. solium accounted for 1.17% (95% CI [0.37-3.17]), according to the T3qPCR. There was sympatric presence of T. solium, T. saginata and T. asiatica. The T3qPCR proved superior to KK and cAgELISA for the detection and differentiation of Taenia species in human feces. Diagnostic sensitivities of 0.94 (95% credible interval (CrI) [0.88-0.98]), 0.82 (95% CrI [0.58-0.95]) and 0.52 (95% CrI [0.07-0.94]), and diagnostic specificities of 0.98 (95% CrI [0.94-1.00]), 0.91 (95% CrI [0.85-0.96]) and 0.99 (95% CrI [0.96-1.00]) were estimated for the diagnosis of taeniasis for the T3qPCR, cAgELISA and KK thick smear in this study, respectively. Conclusions : T3qPCR is not only superior to the KK thick smear and cAgELISA in terms of diagnostic sensitivity and specificity, but it also has the advantage of discriminating between species of Taenia eggs in stools. Application of this newly developed T3qPCR has identified the existence of all three human Taenia tapeworms in Dak Lak province and proves for the first time, the existence of T. asiatica in the Central Highlands and the south of Vietnam

Advanced Air Conditioning Systems Developed from NASA Heat-Pipe Technology

This project exemplifies how NASA technology can be transferred to the market place in the scope of a Technology Utilization contract. In 1983, Dinh Company, a small R~D business, was trying to develop a S~lar Air Conditioner. Dinh Company conceived a Heat-Pipe system to increase the dehumidification of air conditioners therefore increasing their efficiency in providing comfort in humid climates. This l\u27esearch work attracted the attention of the TU officers at NASA/KSC who contacted Khanh Dinh, President of Dinh Company and started negotiations which resulted in a research contract whereas Dinh Company received from NASA technical support in the fields of Heat Pipes, Photovoltaics and Power Electronics. With this infusion of new technology, Dinh Company developed in a record time: a_High Efficiency air conditioner with one of the highest EER ratings today (EER; 15), an air conditioning system which removes twice more moisture out of the air, a Solar Powered Heat Pump, a Photovoltaic Tracking Generator, a line of low cost Digital Inverters. All of these products becoming commercially available in less than three year\u27s time

Coccidioidomycosis Complement Fixation Titer Trends in the Age of Antifungals.

Coccidioidomycosis is associated with a broad spectrum of illness severity, ranging from asymptomatic or self-limited pulmonary infection to life-threatening manifestations of disseminated disease. Serologic studies before the widespread availability of antifungals established current understanding of serologic kinetics and dynamics. Chart histories and complement fixation (CF) titer trends were analyzed for 434 antifungal-treated coccidioidomycosis patients, who were classified by three infectious disease physicians as having either pulmonary uncomplicated coccidioidomycosis (PUC) (n = 248), pulmonary chronic coccidioidomycosis (PCC) (n = 64), disseminated coccidioidomycosis (DC) not including meningitis (n = 86), or coccidioidal meningitis (CM) (n = 36). The median maximal CF titers were 1:4 for PUC patients, 1:24 for PCC patients, 1:128 for DC patients, and 1:32 for CM patients. Approximately 25.4% of PUC patients, 6.2% of PCC patients, 2.3% of DC patients, and 8.3% of CM patients did not develop detectable titers during the study period. Maximal titers developed a mean of 31 days (95% confidence interval [CI], 13 to 50 days) after initial serologic positivity, with no significant differences between groups. Serologic recurrence occurred in 9% of PUC patients, 36% of PCC patients, 50% of DC patients, and 52% of CM patients. Median titer improvement rates were 91 days/dilution for PUC patients, 112 days/dilution for PCC patients, 136 days/dilution for DC patients, and 146 days/dilution for CM patients. Receiver operating characteristic (ROC) analysis revealed that CF testing retains moderate classification value for disseminated infections (area under the curve [AUC], 0.82 [95% CI, 0.78 to 0.87]) and complicated infections (AUC, 0.82 [95% CI, 0.77 to 0.86]). A suitable cutoff value for complicated infections is ≥1:32. Findings update serologic parameters that are relevant for clinical assessment of coccidioidomycosis patients in the triazole era

Detection of the Central Star of the Planetary Nebula NGC 6302

NGC 6302 is one of the highest ionization planetary nebulae known and shows emission from species with ionization potential >300eV. The temperature of the central star must be >200,000K to photoionize the nebula, and has been suggested to be up to ~ 400,000K. On account of the dense dust and molecular disc, the central star has not convincingly been directly imaged until now. NGC 6302 was imaged in six narrow band filters by Wide Field Camera 3 on HST as part of the Servicing Mission 4 Early Release Observations. The central star is directly detected for the first time, and is situated at the nebula centre on the foreground side of the tilted equatorial disc. The magnitudes of the central star have been reliably measured in two filters(F469N and F673N). Assuming a hot black body, the reddening has been measured from the (4688-6766\AA) colour and a value of c=3.1, A_v=6.6 mag determined. A G-K main sequence binary companion can be excluded. The position of the star on the HR diagram suggests a fairly massive PN central star of about 0.64,M_sun close to the white dwarf cooling track. A fit to the evolutionary tracks for (T,L,t)=(200,000K, 2000L_sun, 2200yr), where t is the nebular age, is obtained; however the luminosity and temperature remain uncertain. The model tracks predict that the star is rapidly evolving, and fading at a rate of almost 1 % per year. Future observations could test this prediction.Comment: 13 pages, 5 figures, submitted to ApJ Letters on 25.09.2009 accepted on 19.10.200