Multi-spot ultrafast laser ablation at ambient pressure – A new window on coalescing shock wave interactions

During ultrafast laser ablation at ambient pressure, redeposition of nano-particulates occurs through backwards flux towards the end of the ablation process and is often viewed as undesirable. Here, on the contrary, we report on unique, highly symmetric redeposition patterns observed during ultrafast laser ablation of metals with closely spaced multi-spots in ambient gases. Spot symmetries were altered with a Spatial Light Modulator or beam splitting optics. At low fluence (relative to material ablation threshold), debris is highly confined within the spot patterns, while at higher fluence, jets of debris emanate along axes of symmetry reaching distances far exceeding the spot separations. These phenomena appear universal but depend on the spot proximity, substrate, ambient gas density and pulse energy. The jets, formed at the collision planes between plasma plumes, consist of agglomerated nanoparticle debris, lifted and accelerated by colliding supersonic Mach shocks whose early interactions are imprinted on the debris fields. Numerical simulation using computational fluid dynamics (CFD) of multi-spot ablation in ambient gas supports this view of the phenomena. These observations are relevant to an improved understanding of coalescing shock waves, induced air flows and re-deposition at ambient pressure

First order phase transition from ferromagnetism to antiferromagnetism in Ce(Fe0.96_{0.96}Al0.04_{0.04})2_2

Taking the pseudobinary C15 Laves phase compound Ce(Fe$_{0.96}$Al$_{0.04}$)$_2$ as a paradigm for studying a ferromagnetic to antiferromagnetic phase transition, we present interesting thermomagnetic history effects in magnetotransport as well as magnetisation measurements across this phase transition. A comparison is made with history effects observed across the ferromagnetic to antiferromagnetic transition in R$_{0.5}$Sr$_{0.5}$MnO$_3$ crystals.Comment: 11 pages of text and 4 figures; submitted to Physical Review Letter

Dermacentor reticulatus: a vector on the rise

Dermacentor reticulatus is a hard tick species with extraordinary biological features. It has a high reproduction rate, a rapid developmental cycle, and is also able to overcome years of unfavourable conditions. Dermacentor reticulatus can survive under water for several months and is cold-hardy even compared to other tick species. It has a wide host range: over 60 different wild and domesticated hosts are known for the three active developmental stages. Its high adaptiveness gives an edge to this tick species as shown by new data on the emergence and establishment of D. reticulatus populations throughout Europe. The tick has been the research focus of a growing number of scientists, physicians and veterinarians. Within the Web of Science database, more than a fifth of the over 700 items published on this species between 1897 and 2015 appeared in the last three years (2013–2015). Here we attempt to synthesize current knowledge on the systematics, ecology, geographical distribution and recent spread of the species and to highlight the great spectrum of possible veterinary and public health threats it poses. Canine babesiosis caused by Babesia canis is a severe leading canine vector-borne disease in many endemic areas. Although less frequently than Ixodes ricinus, D. reticulatus adults bite humans and transmit several Rickettsia spp., Omsk haemorrhagic fever virus or Tick-borne encephalitis virus. We have not solely collected and reviewed the latest and fundamental scientific papers available in primary databases but also widened our scope to books, theses, conference papers and specialists colleagues’ experience where needed. Besides the dominant literature available in English, we also tried to access scientific literature in German, Russian and eastern European languages as well. We hope to inspire future research projects that are necessary to understand the basic life-cycle and ecology of this vector in order to understand and prevent disease threats. We conclude that although great strides have been made in our knowledge of the eco-epidemiology of this species, several gaps still need to be filled with basic research, targeting possible reservoir and vector roles and the key factors resulting in the observed geographical spread of D. reticulatus. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1186/s13071-016-1599-x) contains supplementary material, which is available to authorized users

Untersuchungen zur Zusammenarbeit von Elternvertretungen und Eltern unter besonderer Beruecksichtigung der Befaehigung von Klassenelternaktiven zur Einflussnahme auf die Familienerziehung

HUB(11) - 86 HB 4791 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Untersuchungen zur Zusammenarbeit von Elternvertretungen und Eltern unter besonderer Beruecksichtigung der Befaehigung von Klassenelternaktiven zur Einflussnahme auf die Familienerziehung

HUB(11) - 86 HB 4791 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekSIGLEDEGerman

Resistance of the Lichen Buellia frigidato Simulated Space Conditions during the Preflight Tests for BIOMEX—Viability Assay and Morphological Stability

Samples of the extremotolerant Antarctic endemite lichen Buellia frigida are currently exposed to low-Earth orbit– space and simulated Mars conditions at the Biology and Mars Experiment (BIOMEX), which is part of the ESA mission EXPOSE-R2 on the International Space Station and was launched on 23 July 2014. In preparation for the mission, several preflight tests (Experimental and Scientific Verification Tests, EVT and SVT) assessed the sample preparation and hardware integration procedures as well as the resistance of the candidate organism toward the abiotic stressors experienced under space and Mars conditions. Therefore, we quantified the post-exposure viability with a live/dead staining technique utilizing FUN-1 and confocal laser scanning microscopy (CLSM). In addition, we used scanning electron microscopy (SEM) to investigate putative patterns of morphological-anatomical damage that lichens may suffer under the extreme exposure conditions. The present results demonstrate that Buellia frigida is capable of surviving the conditions tested in EVT and SVT. The mycobiont showed lower average impairment of its viability than the photobiont (viability rates of >83% and >69%, respectively), and the lichen thallus suffered no significant damage in terms of thalline integrity and symbiotic contact. These results will become essential to substantiate and validate the results prospectively obtained from the returning space mission. Moreover, they will help assess the limits and limitations of terrestrial organisms under space and Mars conditions as well as characterize the adaptive traits that confer lichen extremotolerance

Influence of Sol-Gel coatings on the corrosion behaviour of MgZn1 foams with 30 % porosity

The aim of this study was to investigate the ion release behaviour of MgZn1 foam with 30 % porosity and three different sol-gel coatings by static immersion test. Compared to uncoated samples the corrosion could be reduced significantly with all three coatings. Under these test conditions Coating 1 revealed the best corrosion protection

Mechanical Characteristics, In Vitro Degradation, Cytotoxicity, and Antibacterial Evaluation of Zn-4.0Ag Alloy as a Biodegradable Material

Zn-based biodegradable metallic materials have been regarded as new potential biomaterials for use as biodegradable implants, mainly because of the ideal degradation rate compared with those of Mg-based alloys and Fe-based alloys. In this study, we developed and investigated a novel Zn-4 wt % Ag alloy as a potential biodegradable metal. A thermomechanical treatment was applied to refine the microstructure and, consequently, to improve the mechanical properties, compared to pure Zn. The yield strength (YS), ultimate tensile strength (UTS) and elongation of the Zn-4Ag alloy are 157 MPa, 261 MPa, and 37%, respectively. The corrosion rate of Zn-4Ag calculated from released Zn ions in DMEM extracts is approximately 0.75 ± 0.16 μg cm–2 day–1, which is higher than that of pure Zn. In vitro cytotoxicity tests showed that the Zn-4Ag alloy exhibits acceptable toxicity to L929 and Saos-2 cells, and could effectively inhibit initial bacteria adhesion. This study shows that the Zn-4Ag exhibits excellent mechanical properties, predictable degradation behavior, acceptable biocompatibility, and effective antibacterial properties, which make it a candidate biodegradable material

Reach out emergency department: Partnering with an economically disadvantaged community in the development of a text-messaging intervention to address high blood pressure

© 2020 Society for Public Health Education. Background. Hypertension affects nearly 30% of the U.S. adult population. Due to the ubiquitous nature of mobile phone usage, text messaging offers a promising platform for interventions to assist in the management of chronic diseases including hypertension, including among populations that are historically underserved. We present the intervention development of Reach Out, a health behavior theory–based, mobile health intervention to reduce blood pressure among hypertensive patients evaluated in a safety net emergency department primarily caring for African Americans. Aims. To describe the process of designing and refining text messages currently being implemented in the Reach Out randomized controlled trial. Method. We used a five-step framework to develop the text messages used in Reach Out. These steps included literature review and community formative research, conception of a community-centered behavioral theoretical framework, draft of evidence-based text messages, community review, and revision based on community feedback and finalization. Results. The Reach Out development process drew from pertinent evidence that, combined with community feedback, guided the development of a community-centered health behavior theory framework that led to development of text messages. A total of 333 generic and segmented messages were created. Messages address dietary choices, physical activity, hypertension medication adherence, and blood pressure monitoring. Discussion. Our five-step framework is intended to inform future text-messaging-based health promotion efforts to address health issues in vulnerable populations. Conclusion. Text message–based health promotion programs should be developed in partnership with the local community to ensure acceptability and relevance