Optimal generation of spatially coherent soft X-ray isolated attosecond pulses in a gas-filled waveguide using two-color synthesized laser pulses

We numerically demonstrate the generation of intense, low-divergence soft X-ray isolated attosecond pulses in a gas-filled hollow waveguide using synthesized few-cycle two-color laser waveforms. The waveform is a superposition of a fundamental and its second harmonic optimized such that highest harmonic yields are emitted from each atom. We then optimize the gas pressure and the length and radius of the waveguide such that bright coherent high-order harmonics with angular divergence smaller than 1 mrad are generated, for photon energy from the extreme ultraviolet to soft X-rays. By selecting a proper spectral range enhanced isolated attosecond pulses are generated. We study how dynamic phase matching caused by the interplay among waveguide mode, neutral atomic dispersion, and plasma effect is achieved at the optimal macroscopic conditions, by performing time-frequency analysis and by analyzing the evolution of the driving laser’s electric field during the propagation. Our results, when combined with the on-going push of high-repetition-rate lasers (sub- to few MHz’s) may eventually lead to the generation of high-flux, low-divergence soft X-ray tabletop isolated attosecond pulses for applications.Fundamental Research Funds for the Central Universities of China (Grant No. 30916011207)United States. Department of Energy. Office of Science (Grant No. DE-FG02-86ER13491)United States. Air Force Office of Scientific Research (Grant No. FA9550- 14-1-0255

Enzyme Attached on Polymeric Micelles as a Nanoscale Reactor

Similar to what lipase does, a surface-active enzyme was developed by attaching peroxidase on combshaped polymaleic anhydride-alt-1-tetradecene (PMA-TD) in a microemulsion system composed of n-butyl acetate and buffer solution, and its catalytic characteristics of polyphenol synthesis were investigated in an aqueous solution. The modified peroxidase with PMA-TD tended to form self-assembled aggregates like micelles in the aqueous solution and could be concentrated at solvent/water interfaces without unfolding of the enzyme. The efficiency of conversion of 2,4-dichlorophenol to phenolic oligomers was approximately 2-fold improved with the modified peroxidase compared to native peroxidase. The K m and V max values for the modified peroxidase were 1.5-fold lower and 2-fold higher, respectively. The hydrodynamic diameter of the micelle on the modified peroxidase increased with the reaction time, indicating that phenolic products were accumulated in the hydrophobic interior of micelles. In addition, the molecular weight (MW) of phenolic polymers was much larger in the system with the modified peroxidase. These observations implied that the modified peroxidase with hydrophobic side chains formed micellar structures by solubilization of phenolic products and further polymerization reaction could occur in the hydrophobic interior of the micelles

Enzyme Attached on Polymeric Micelles as a Nanoscale Reactor

Similar to what lipase does, a surface-active enzyme was developed by attaching peroxidase on combshaped polymaleic anhydride-alt-1-tetradecene (PMA-TD) in a microemulsion system composed of n-butyl acetate and buffer solution, and its catalytic characteristics of polyphenol synthesis were investigated in an aqueous solution. The modified peroxidase with PMA-TD tended to form self-assembled aggregates like micelles in the aqueous solution and could be concentrated at solvent/water interfaces without unfolding of the enzyme. The efficiency of conversion of 2,4-dichlorophenol to phenolic oligomers was approximately 2-fold improved with the modified peroxidase compared to native peroxidase. The K m and V max values for the modified peroxidase were 1.5-fold lower and 2-fold higher, respectively. The hydrodynamic diameter of the micelle on the modified peroxidase increased with the reaction time, indicating that phenolic products were accumulated in the hydrophobic interior of micelles. In addition, the molecular weight (MW) of phenolic polymers was much larger in the system with the modified peroxidase. These observations implied that the modified peroxidase with hydrophobic side chains formed micellar structures by solubilization of phenolic products and further polymerization reaction could occur in the hydrophobic interior of the micelles

Estimation of hospital-based HIV seroprevalence as a nationwide scale by novel method; 2002-2008 in Korea

<p>Abstract</p> <p>Background</p> <p>In Korea, approximately 70% of HIV-positive individuals are currently diagnosed in hospitals, while most HIV-positive patients were diagnosed at public health centers in 1980 s and 1990 s. However, there are no reporting systems to identify how many HIV tests are performed in the Korean hospitals different from public health centers and Blood centers. We estimated how many HIV tests were performed in hospitals and analyzed the nationwide hospital-based HIV seroprevalence in the present study.</p> <p>Methods</p> <p>Between 2002 and 2008, data included HIV tests on insurance claims in hospitals and the proportion of computerized insurance claims from the Health Insurance Review and Assessment Services. The number of HIV tests from the survey in the External Quality Assurance Scheme for hospital laboratories was collected to calculate the insurance claim proportion. HIV seroprevalence was estimated using data of tested individuals, including infected individuals. Statistical analysis was confirmed with the 95% confidence interval. Statistical significance was defined at p-values < 0.05.</p> <p>Results</p> <p>The number of HIV tests in hospitals increased from 2.7 million in 2002 to 5.0 million in 2008. The trend of HIV seroprevalence was decrease (1.5-1.3 per 10,000 individuals, P < 0.0028), except in 2002. The number of women tested was greater than men, and the proportion increased in older individuals and in small towns. Men had a higher annual HIV seroprevalence than women (P < 0.0001). The annual seroprevalence decreased in men (P = 0.0037), but was stable in women. The seroprevalence in the 30-39 year age group demonstrated higher than other age groups except 2008.</p> <p>Conclusions</p> <p>The nationwide hospital-based number of HIV tests and seroprevalence were estimated using a new method and seroprevalence trends were identified. This information will facilitate improvement in national HIV prevention strategies.</p

Importance of remission and residual somatic symptoms in health-related quality of life among outpatients with major depressive disorder: a cross-sectional study

Background: Major depressive disorder (MDD) is strongly associated with an impaired quality of life (QoL), which is itself affected by various factors. Symptom-oriented ratings poorly reflect the impact of disease on the QoL and level of functioning of the mental health of subjects. The purpose of this study was to assess health-related QoL (HRQoL) using preference-based measures in outpatients with MDD with regard to their remission achievement and clinical factors affecting the HRQoL. Methods: This was a cross-sectional observational study. We recruited 811 patients with MDD from 14 psychiatric outpatient clinics in Korea. They were divided into three groups as follows: a new visit group (n = 287), a remitted group (n = 235), and a non-remitted group (n = 289). The 17-item Hamilton Depression Rating Scale was used to assign patients to the remitted or non-remitted group. The general HRQoL was assessed with the EuroQol 5D (EQ-5D), using both the EQ-5D index score and the EuroQol Visual Analog Scale (EQ-VAS). The disease-specific HRQoL was assessed with the Quality of Life Enjoyment and Satisfaction Questionnaire Short Form (Q-LES-Q-SF). Results: The non-remitted group showed a significant impairment of HRQoL in view of the subscales of EQ-5D index scores, EQ-VAS, and Q-LES-Q-SF. The EQ-5D index score in the remitted group was 0.77 ± 0.10, while it was 0.57 ± 0.23 in the non-remitted group and 0.58 ± 0.24 in the new visit group (p < 0.0001). The EQ-VAS scores for the remitted and non-remitted groups were 72.5 ± 16.6 and 50.9 ± 20.3, respectively (p < 0.0001). Likewise, patients with remission had the Q-LES-Q-SF total score of 46.5 ± 8.8, whereas those with non-remission reported 36.7 ± 7.7 (p < 0.0001). The symptom severity measured by the Depression and Somatic Symptoms Scale was significantly correlated with the HRQoL. Furthermore, patients with severe somatic symptoms showed a significantly lower EQ-5D index score (0.54 ± 0.24) than those with mild/moderate somatic symptoms (0.75 ± 0.12; p = 0.002). Conclusion: Non-remitted MDD patients, especially those with more severe somatic symptoms, show a distinct impairment of HRQoL and more clinical symptoms, suggesting the importance of achieving remission in the treatment of MDD

Technological Progress in Generation of Induced Pluripotent Stem Cells for Clinical Applications

Reprogramming of somatic cells into induced pluripotent stem cells (iPSCs) is achieved by viral-mediated transduction of defined transcription factors. Generation of iPSCs is of great medical interest as they have the potential to be a source of patient-specific cells. For the eventual goal of clinical application, it is necessary to overcome the limitations of low reprogramming efficiency and chromosomal abnormalities due to viral DNA integration. In this paper, we summarize the current state of reprogramming technology for generation of iPSCs and also discuss potential approaches to the development of safe iPSCs for personalized cell-based replacement therapy