Helium-3 and Helium-4 acceleration by high power laser pulses for hadron therapy

The laser driven acceleration of ions is considered a promising candidate for an ion source for hadron therapy of oncological diseases. Though proton and carbon ion sources are conventionally used for therapy, other light ions can also be utilized. Whereas carbon ions require 400 MeV per nucleon to reach the same penetration depth as 250 MeV protons, helium ions require only 250 MeV per nucleon, which is the lowest energy per nucleon among the light ions. This fact along with the larger biological damage to cancer cells achieved by helium ions, than that by protons, makes this species an interesting candidate for the laser driven ion source. Two mechanisms (Magnetic Vortex Acceleration and hole-boring Radiation Pressure Acceleration) of PW-class laser driven ion acceleration from liquid and gaseous helium targets are studied with the goal of producing 250 MeV per nucleon helium ion beams that meet the hadron therapy requirements. We show that He3 ions, having almost the same penetration depth as He4 with the same energy per nucleon, require less laser power to be accelerated to the required energy for the hadron therapy.Comment: 8 pages, 3 figures, 1 tabl

Surgical treatment versus medical treatment in hypertrophic obstructive cardiomyopathy

Sixty-three patients operated upon for HOCM and 49 patients selected for non-surgical treatment have been followed-up for 15 years. Pre-operatively, surgical patients had a higher left ventricular outflow tract gradient at rest and, on the average, more severe symptoms than non-surgical patients. Septal myectomy relieved the pressure gradient and symptoms more consistently than long-term treatment with β-blockers or verapamil. Within an average observation time of 7½ years, there was late deterioration or death in almost half of the non-surgical patients but in less than one-quarter in the operated patients. The 10 year mortality rate was 80% in the surgical series and 71% in the non-surgical series. In operated patients, pre-operative symptomatic status was significantly related to early and late mortality. In medically treated patients, mortality was unrelated to symptoms; however, it was significantly lower in patients receiving long term treatment with β-blockers or verapamil. In conclusion, a high basal pressure gradient associated to limiting symptoms is a clear-cut indication for surgery. Other indications are more debatable. In medically treated patients, long-term administration of β-blockers or verapamil is beneficial even without symptoms as it appears to improve prognosi

Enhanced ozone strongly reduces carbon sink strength of adult beech (Fagus sylvatica) – Resume from the free-air fumigation study at Kranzberg Forest

Ground-level ozone (O3) has gained awareness as an agent of climate change. In this respect, key results are comprehended from a unique 8-year free-air O3-fumigation experiment, conducted on adult beech (Fagus sylvatica) at Kranzberg Forest (Germany). A novel canopy O3 exposure methodology was employed that allowed whole-tree assessment in situ under twice-ambient O3 levels. Elevated O3 significantly weakened the C sink strength of the tree–soil system as evidenced by lowered photosynthesis and 44% reduction in whole-stem growth, but increased soil respiration. Associated effects in leaves and roots at the gene, cell and organ level varied from year to year, with drought being a crucial determinant of O3 responsiveness. Regarding adult individuals of a late-successional tree species, empirical proof is provided first time in relation to recent modelling predictions that enhanced ground-level O3 can substantially mitigate the C sequestration of forests in view of climate change

Who will use pre-exposure prophylaxis (PrEP) and why?: Understanding PrEP awareness and acceptability amongst men who have sex with men in the UK – a mixed methods study

Background: Recent clinical trials suggest that pre-exposure prophylaxis (PrEP) may reduce HIV transmission by up to 86% for men who have sex with men (MSM), whilst relatively high levels of PrEP acceptability have been reported to date. This study examines PrEP awareness amongst sub-groups of MSM communities and acceptability amongst MSM in a low prevalence region (Scotland, UK), using a mixed methods design. Methods: Quantitative surveys of n = 690 MSM recruited online via social and sociosexual media were analysed using descriptive statistics and multivariate logistic regression. In addition, n = 10 in-depth qualitative interviews with MSM were analysed thematically. Results: Under one third (29.7%) of MSM had heard of PrEP, with awareness related to living in large cities, degree level education, commercial gay scene use and reporting an HIV test in the last year. Just under half of participants (47.8%) were likely to use PrEP if it were available but there was no relationship between PrEP acceptability and previous PrEP awareness. Younger men (18–25 years) and those who report higher risk UAI were significantly more likely to say they would use PrEP. Qualitative data described specific PrEP scenarios, illustrating how risk, patterns of sexual practice and social relationships could affect motivation for and nature of PrEP use. Conclusion: These findings suggest substantial interest PrEP amongst MSM reporting HIV risk behaviours in Scotland. Given the Proud results, there is a strong case to investigate PrEP implementation within the UK. However, it appears that disparities in awareness have already emerged along traditional indicators of inequality. Our research identifies the need for comprehensive support when PrEP is introduced, including a key online component, to ensure equity of awareness across diverse MSM communities (e.g. by geography, education, gay scene use and HIV proximity), as well as to responding to the diverse informational and sexual health needs of all MSM communities

Multiple Measures Reveal Antiretroviral Adherence Successes and Challenges in HIV-Infected Ugandan Children

Background: Adherence to HIV antiretroviral therapy (ART) among children in developing settings is poorly understood. Methodology/Principal Findings: To understand the level, distribution, and correlates of ART adherence behavior, we prospectively determined monthly ART adherence through multiple measures and six-monthly HIV RNA levels among 121 Ugandan children aged 2–10 years for one year. Median adherence levels were 100% by three-day recall, 97.4% by 30-day visual analog scale, 97.3% by unannounced pill count/liquid formulation weights, and 96.3% by medication event monitors (MEMS). Interruptions in MEMS adherence of $\geq$48 hours were seen in 57.0% of children; 36.3% had detectable HIV RNA at one year. Only MEMS correlated significantly with HIV RNA levels (r = −0.25, p = 0.04). Multivariable regression found the following to be associated with <90% MEMS adherence: hospitalization of child (adjusted odds ratio [AOR] 3.0, 95% confidence interval [CI] 1.6–5.5; p = 0.001), liquid formulation use (AOR 1.4, 95%CI 1.0–2.0; p = 0.04), and caregiver’s alcohol use (AOR 3.1, 95%CI 1.8–5.2; p<0.0001). Child’s use of co-trimoxazole (AOR 0.5, 95%CI 0.4–0.9; p = 0.009), caregiver’s use of ART (AOR 0.6, 95%CI 0.4–0.9; p = 0.03), possible caregiver depression (AOR 0.6, 95%CI 0.4–0.8; p = 0.001), and caregiver feeling ashamed of child’s HIV status (AOR 0.5, 95%CI 0.3–0.6; p<0.0001) were protective against <90% MEMS adherence. Change in drug manufacturer (AOR 4.1, 95%CI 1.5–11.5; p = 0.009) and caregiver’s alcohol use (AOR 5.5, 95%CI 2.8–10.7; p<0.0001) were associated with $\geq$48-hour interruptions by MEMS, while second-line ART (AOR 0.3, 95%CI 0.1–0.99; p = 0.049) and increasing assets (AOR 0.7, 95%CI 0.6–0.9; p = 0.0007) were protective against these interruptions. Conclusions/Significance: Adherence success depends on a well-established medication taking routine, including caregiver support and adequate education on medication changes. Caregiver-reported depression and shame may reflect fear of poor outcomes, functioning as motivation for the child to adhere. Further research is needed to better understand and build on these key influential factors for adherence intervention development

Structure and expression analysis of rice paleo duplications

Having a well-known history of genome duplication, rice is a good model for studying structural and functional evolution of paleo duplications. Improved sequence alignment criteria were used to characterize 10 major chromosome-to-chromosome duplication relationships associated with 1440 paralogous pairs, covering 47.8% of the rice genome, with 12.6% of genes that are conserved within sister blocks. Using a micro-array experiment, a genome-wide expression map has been produced, in which 2382 genes show significant differences of expression in root, leaf and grain. By integrating both structural (1440 paralogous pairs) and functional information (2382 differentially expressed genes), we identified 115 paralogous gene pairs for which at least one copy is differentially expressed in one of the three tissues. A vast majority of the 115 paralogous gene pairs have been neofunctionalized or subfunctionalized as 88%, 89% and 96% of duplicates, respectively, expressed in grain, leaf and root show distinct expression patterns. On the basis of a Gene Ontology analysis, we have identified and characterized the gene families that have been structurally and functionally preferentially retained in the duplication showing that the vast majority (>85%) of duplicated have been either lost or have been subfunctionalized or neofunctionalized during 50–70 million years of evolution

Nitrogen-Functionalized Graphene Nanoflakes (GNFs:N): Tunable Photoluminescence and Electronic Structures

This study investigates the strong photoluminescence (PL) and X-ray excited optical luminescence observed in nitrogen-functionalized 2D graphene nanoflakes (GNFs:N), which arise from the significantly enhanced density of states in the region of {\pi} states and the gap between {\pi} and {\pi}* states. The increase in the number of the sp2 clusters in the form of pyridine-like N-C, graphite-N-like, and the C=O bonding and the resonant energy transfer from the N and O atoms to the sp2 clusters were found to be responsible for the blue shift and the enhancement of the main PL emission feature. The enhanced PL is strongly related to the induced changes of the electronic structures and bonding properties, which were revealed by the X-ray absorption near-edge structure, X-ray emission spectroscopy, and resonance inelastic X-ray scattering. The study demonstrates that PL emission can be tailored through appropriate tuning of the nitrogen and oxygen contents in GNFs and pave the way for new optoelectronic devices.Comment: 8 pages, 6 figures (including toc figure