The spatial location of laser-driven, forward-propagating waves in a National-Ignition-Facility-relevant plasma

Ion acoustic and electron plasma waves, associated with backward-propagating stimulated Brillouin scattering and stimulated Raman scattering, have been diagnosed in a long-scale-length, nearly homogenous plasma with transverse flow. Thomson scattered light from a probe beam is employed to show that these waves are well localized in space and for a time much shorter than the laser pulse duration. These plasma conditions are relevant to hohlraum design for the National Ignition Facility inertial confinement fusion laser system. [R. Sawicki et al., Fusion Technol. 34, 1097 (1998)]. © 2000 American Institute of Physics.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/71338/2/PHPAEN-7-1-323-1.pd

Experimental Program to Elucidate and Control Stimulated Brillouin and Raman Backscattering in Long-Scale Plasmas

Laser-plasma instability is a serious concern for indirect-drive inertial confinement fusion (ICF), where laser beams illuminate the interior of a cavity (called a hohlraum) to produce X-rays to drive the implosion of a fusion capsule. Stimulated Raman and Brillouin backscattering (SRS and SBS) could result in unacceptably high laser reflectivities. Unfortunately, it is impossible at present to fully simulate these processes realistically. The authors experimental program aims to understand these instabilities by pursuing a dual strategy. (1) They use a gas-filled hohlraum design, which best approaches ignition-hohlraum conditions, on the Nova laser to identify important non linear trends. (2) They are shifting towards more fundamental experiments with a nearly diffraction-limited interaction laser beam illuminating extremely well characterized plasmas on the Trident laser facility at Los Alamos to probe the relevant fundamental processes

Radiation temperature measurements in laser-heated hohlraums

Two x-ray spectrographs have been used on the Trident laser at LANL to monitor the radiation temperature of small Au hohlraums. The cylindrical targets are smaller than 1 mm. The x radiation produced by {approximately} 400 J of 0.53-{micro}m laser light is detected with a 7-channel VNIIEF soft-x-ray spectrometer. Each channel employs a multi-layer mirror and a filter to limit the channel bandwidth to 1--3% of the channel energy. X rays are detected with calibrated Al x-ray diodes. A second spectrometer is based on a free-standing Au transmission grating for spectral dispersion and a multi-channel diamond photo-conductive device detector. The small hohlraum results are consistent with radiation temperatures exceeding 100 eV. Simple computer modeling shows that late in the plasma discharge, radiation of this temperature is emitted from the target

‘The only way is Essex’: Gender, union and mobilisation among fire service control room staff

This contribution to On the Front Line records a dialogue between two female Fire Brigades Union (FBU) representatives in the Essex Emergency Control Room who led industrial action over the imposition of a shift system that stretched their work–life balance to breaking point and constrained their ability to work full-time. Their testimony reveals how male members were mobilised in the interests of predominantly female control staff. Kate and Lynne’s discussion illuminates the interaction of gender and class interests and identities in the union and in the lives of its women members. It provides insight into the efficacy of trade unions for women’s collective action

Sitagliptin reduces cardiac apoptosis, hypertrophy and fibrosis primarily by insulin-dependent mechanisms in experimental type-II diabetes. Potential roles of GLP-1 isoforms

Background:Myocardial fibrosis is a key process in diabetic cardiomyopathy. However, their underlying mechanisms have not been elucidated, leading to a lack of therapy. The glucagon-like peptide-1 (GLP-1) enhancer, sitagliptin, reduces hyperglycemia but may also trigger direct effects on the heart.Methods:Goto-Kakizaki (GK) rats developed type-II diabetes and received sitagliptin, an anti-hyperglycemic drug (metformin) or vehicle (n=10, each). After cardiac structure and function assessment, plasma and left ventricles were isolated for biochemical studies. Cultured cardiomyocytes and fibroblasts were used for in vitro assays.Results:Untreated GK rats exhibited hyperglycemia, hyperlipidemia, plasma GLP-1 decrease, and cardiac cell-death, hypertrophy, fibrosis and prolonged deceleration time. Moreover, cardiac pro-apoptotic/necrotic, hypertrophic and fibrotic factors were up-regulated. Importantly, both sitagliptin and metformin lessened all these parameters. In cultured cardiomyocytes and cardiac fibroblasts, high-concentration of palmitate or glucose induced cell-death, hypertrophy and fibrosis. Interestingly, GLP-1 and its insulinotropic-inactive metabolite, GLP-1(9-36), alleviated these responses. In addition, despite a specific GLP-1 receptor was only detected in cardiomyocytes, GLP-1 isoforms attenuated the pro-fibrotic expression in cardiomyocytes and fibroblasts. In addition, GLP-1 receptor signalling may be linked to PPARδ activation, and metformin may also exhibit anti-apoptotic/necrotic and anti-fibrotic direct effects in cardiac cells.Conclusions:Sitagliptin, via GLP-1 stabilization, promoted cardioprotection in type-II diabetic hearts primarily by limiting hyperglycemia e hyperlipidemia. However, GLP-1 and GLP-1(9-36) promoted survival and anti-hypertrophic/fibrotic effects on cultured cardiac cells, suggesting cell-autonomous cardioprotective actionsThis work was supported by national funding from Ministerio de Educación y Ciencia (SAF2009-08367), Comunidad de Madrid (CCG10-UAM/ BIO-5289), and a unrestricted grant from by Merck/MS

Detailed studies of the transverse beam characteristics of laser produced ion beams

We present the first systematic measurement of the transverse parameters of laser produced proton beam. We find a similarity for the shape of the accelerating sheath, which is always close to a parabola. We find also a similarity for the relation between source size and proton energy with the maximum source size and proton energy as a free parameter, which is confirming the similarity we already found for the sheath shape. This is of particular interest for the application of laser produced proton beams as it shows the scalability of the transverse beam parameter

Avian Influenza in Wild Birds: Environmental Sampling for the Rapid Detection of Avian Influenza Viruses

All subtypes of influenza Type A viruses infect wild birds, especially waterfowl and shorebirds, but rarely cause disease or mortality in these aquatic species. Aquatic birds are the natural reservoirs for low pathogenic avian influenza viruses (LPAI) that are distributed globally. However, some AI subtypes can be virulent in other animals and humans and some highly pathogenic AI viruses (HPAI) have caused major outbreaks in poultry and even pandemics in the human population. The emergence of a HPAl H5N1 subtype in southeast Asian poultry in 1997 subsequently involved migratory waterfowl in 2005 and has since spread westward throughout the Asian, European, and African continents. This rapid continental spread planned animal and human health agencies in North America and initiated the establishment of a National Strategy for Pandemic influenza in the United States to increase and expand surveillance for the early detection of this virus, to improve and expand preventative measures, and to develop contingency responses to possible outbreaks. One of the methods of emergency surveillance developed and implemented was an interagency, early detection system for HPAI H5N1 avian influenza in wild migratory birds with the potential to bring in the virus from Asia or Europe and spread it throughout North America. As part of this early detection system, the Wildlife Services National Wildlife Research Center developed testing methods, sampling protocols, guidelines, and analyzed 50,184 avian fecal samples collected by Wildlife Service biologists in 50 states and the U. S. territories. Samples were pooled in the laboratory (n = 10,541 pools) and analyzed using RT-PCR. AI viruses were detected in 4.0% of the 10,541 sample pools analyzed and H5/H7 subtypes were detected in 0.2% of the sample pools. Positive H5 and H7 subtypes were shipped to the National Veterinary Services Laboratory for further evaluation and confirmation. This monitoring effort was successful in detecting AI viruses in environmental samples and has proven to be a rapid and cost effective surveillance method