X-ray phase-contrast imaging for laser-induced shock waves

X-ray phase-contrast imaging (XPCI) is a versatile technique with applications in many fields, including fundamental physics, biology and medicine. Where X-ray absorption radiography requires high density ratios for effective imaging, the image contrast for XPCI is a function of the density gradient. In this letter, we apply XPCI to the study of laser-driven shock waves. Our experiment was conducted at the Petawatt High-Energy Laser for Heavy Ion EXperiments (PHELIX) at GSI. Two laser beams were used: one to launch a shock wave and the other to generate an X-ray source for phase-contrast imaging. Our results suggest that this technique is suitable for the study of warm dense matter (WDM), inertial confinement fusion (ICF) and laboratory astrophysics

Propagation-based imaging phase-contrast enhanced imaging setup for single shot acquisition using laser-generated X-ray sources

The development of new diagnostics is important to improve the interpretation of experiments. Often well-known physical processes and techniques originally developed in unrelated fields of science can be applied to a different area with a significant impact on the quality of the produced data. X-ray phase-contrast imaging (XPCI) is one techniques which has found many applications in biology and medicine. This is due to its capability to emphasise the presence of strong density variations normally oriented with respect to the X-ray propagation direction. With the availability of short energetic X-ray pulses XPCI extends to time-resolved pump-probe measurements of laser-matter interaction where strong density gradient are also present. In this work we present the setup for XPCI tested at the laser PHELiX at GSI in Germany

Assessment of the potential in vivo ecotoxicity of Double-Walled Carbon Nanotubes (DWNTs) in water, using the amphibian Ambystoma mexicanum

Because of their specific properties (mechanical, electrical, etc), carbon nanotubes (CNTs) are being assessed for inclusion in many manufactured products. Due to their massive production and number of potential applications, the impact of CNTs on the environment must be taken into consideration. The present investigation evaluates the ecotoxic potential of CNTs in the amphibian larvae (Ambystoma mexicanum). Acute toxicity and genotoxicity were analysed after 12 days of exposure in laboratory conditions. The genotoxic effects were analysed by scoring the micronucleated erythrocytes in the circulating blood of the larvae according to the French standard micronucleus assay. The results obtained in the present study demonstrated that CNTs are neither acutely toxic nor genotoxic to larvae whatever the CNTs concentration in the water, although black masses of CNTs were observed inside the gut. In the increasing economical context of CNTs, complementary studies must be undertaken, especially including mechanistic and environmental investigations

Cytotoxicity and ion release of alloy nanoparticles

It is well-known that nanoparticles could cause toxic effects in cells. Alloy nanoparticles with yet unknown health risk may be released from cardiovascular implants made of Nickel–Titanium or Cobalt–Chromium due to abrasion or production failure. We show the bio-response of human primary endothelial and smooth muscle cells exposed to different concentrations of metal and alloy nanoparticles. Nanoparticles having primary particle sizes in the range of 5–250 nm were generated using laser ablation in three different solutions avoiding artificial chemical additives, and giving access to formulations containing nanoparticles only stabilized by biological ligands. Endothelial cells are found to be more sensitive to nanoparticle exposure than smooth muscle cells. Cobalt and Nickel nanoparticles caused the highest cytotoxicity. In contrast, Titanium, Nickel–Iron, and Nickel–Titanium nanoparticles had almost no influence on cells below a nanoparticle concentration of 10 μM. Nanoparticles in cysteine dissolved almost completely, whereas less ions are released when nanoparticles were stabilized in water or citrate solution. Nanoparticles stabilized by cysteine caused less inhibitory effects on cells suggesting cysteine to form metal complexes with bioactive ions in media

Self-employment in joinery: An occupational risk facor?

Objectives: Only a few studies have analyzed the health of self-employed workers. This cross-sectional study is the first to compare health status among craftsmen joiners and paid joiners. Material and Methods: Clinical and paraclinical data for self-employed craftsmen and employees were collected by occupational health doctors according to a standardized protocol and compared. Health data and professional status relationships were analyzed by logistic regression. Results: A total of 171 craftsmen and 196 paid workers were included. Craftsmen had more dermatologic pathologies (odds ratio (OR) = 2.67, p < 0.05), ear/nose/throat symptoms (OR = 3.38, p < 0.001), pulmonary symptoms (OR = 2.46, p < 0.05), musculoskeletal symptoms (OR = 3.09, p < 0.001), and abnormal audiogram (OR = 3.50, p < 0.001). The FEV1 was significantly lower among craftsmen (p < 0.01), independently of tobacco smoke exposure. Conclusions: This survey highlights a high morbidity rate among self-employed craftsmen, suggesting that among woodworkers, professional status can be a risk factor for health. The preventive medical system for craftsmen has to be rethought to guarantee better safety for this population

Functional polymorphism of the NFKB1 gene promoter is related to the risk of dilated cardiomyopathy

<p>Abstract</p> <p>Background</p> <p>Previous studies in experimental and human heart failure showed that nuclear factor kappa B (NF-κB) is chronically activated in cardiac myocytes, suggesting an important involvement of NF-κB in the cardiac remodeling process. A common insertion/deletion (-94 insertion/deletion ATTG, rs28362491) located between two putative key promoter regulatory elements in the <it>NFKB1 </it>gene was identified which seems to be the first potential functional <it>NFKB1 </it>genetic variation. The main goal of the present investigation was to investigate the <it>NFKB1 </it>-94 insertion/deletion ATTG polymorphism in relation to risk of dilated cardiomyopathy (DCM).</p> <p>Methods</p> <p>A total of 177 DCM patients and 203 control subjects were successfully investigated. The <it>NFKB1 </it>-94 insertion/deletion ATTG polymorphism was genotyped by using PCR-PAGE.</p> <p>Results</p> <p>Genotype frequency of <it>NFKB1 </it>-94 insertion/deletion ATTG polymorphism in DCM patients was significantly different from that in control subjects (<it>P </it>= 0.015) and the ATTG₂carrier (ATTG₁/ATTG₂+ ATTG₂/ATTG₂) was susceptible to DCM.</p> <p>Conclusion</p> <p>Our data suggested that <it>NFKB1 </it>-94 insertion/deletion ATTG polymorphism is associated with DCM.</p