Determination of cloud microphysical properties by laser backscattering and extinction measurements

The extinction and backscattering of 514 nm laser radiation in polydisperse water droplet clouds was studied in the laboratory. Three cloud size distributions with modal diameters of 0.02, 5.0, and 12.0 microns were investigated. The relationships between the cloud optical parameters (attentuation coefficient, sigma and volume backscattering coefficient, Beta (sub pi)) and the cloud water content, C, were measured for each size distribution. It was found that a linear relationship exists between sigma and C and between beta (sub pi) and C for cloud water content values up to 3gm/cubic m. The linear relationships obtained, however, have slopes which depend on the droplet size distribution. For a given water content both sigma and beta (sub pi) increase as the modal diameter decreases. The measured data are compared with existing theoretical analyses and discussed in terms of thie application to lidar measurements of atmospheric clouds. It is concluded that the empirical information obtained can serve as a basis for quantitative lidar measurements

The secondary infall model of galactic halo formation and the spectrum of cold dark matter particles on Earth

The spectrum of cold dark matter particles on Earth is expected to have peaks in velocity space associated with particles which are falling onto the Galaxy for the first time and with particles which have fallen in and out of the Galaxy only a small number of times in the past. We obtain estimates for the velocity magnitudes and the local densities of the particles in these peaks. To this end we use the secondary infall model of galactic halo formation which we have generalized to take account of the angular momentum of the dark matter particles. The new model is still spherically symmetric and it admits self-similar solutions. In the absence of angular momentum, the model produces flat rotation curves for a large range of values of a parameter $\epsilon$ which is related to the spectrum of primordial density perturbations. We find that the presence of angular momentum produces an effective core radius, i.e. it makes the contribution of the halo to the rotation curve go to zero at zero radius. The model provides a detailed description of the large scale properties of galactic halos including their density profiles, their extent and total mass. We obtain predictions for the kinetic energies of the particles in the velocity peaks and estimates for their local densities as functions of the amount of angular momentum, the age of the universe and $\epsilon$.Comment: LaTeX, 39 pages including 18 figure

Neurochemical changes in Huntington R6/2 mouse striatum detected by in vivo 1H NMR spectroscopy

The neurochemical profile of the striatum of R6/2 Huntington's disease mice was examined at different stages of pathogenesis using in vivo1H NMR spectroscopy at 9.4 T. Between 8 and 12 weeks, R6/2 mice exhibited distinct changes in a set of 17 quantifiable metabolites compared with littermate controls. Concentrations of creatine, glycerophosphorylcholine, glutamine and glutathione increased and N-acetylaspartate decreased at 8 weeks. By 12 weeks, concentrations of phosphocreatine, taurine, ascorbate, glutamate, and myo-inositol increased and phophorylethanolamine decreased. These metabolic changes probably reflected multiple processes, including compensatory processes to maintain homeostasis, active at different stages in the development of HD. The observed changes in concentrations suggested impairment of neurotransmission, neuronal integrity and energy demand, and increased membrane breakdown, gliosis, and osmotic and oxidative stress. Comparisons between metabolite concentrations from individual animals clearly distinguished HD transgenics from non-diseased littermates and identified possible markers of disease progression. Metabolic changes in R6/2 striata were distinctly different from those observed previously in the quinolinic acid and 3NP models of HD. Longitudinal monitoring of changes in these metabolites may provide quantifiable measures of disease progression and treatment effects in both mouse models of HD and patients. © 2007 The Authors

Dietary patterns are not associated with disease activity among patients with inflammatory conditions of the pouch in a prospective cohort

BACKGROUND: Evidence-based recommendations regarding the influence of diet on inflammatory conditions of the pouch after restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) are limited. METHODS: We analyzed dietary patterns at enrollment in a prospective registry of patients with 1 of 4 inflammatory conditions of the pouch (acute pouchitis, chronic antibiotic-dependent pouchitis, chronic antibiotic refractory pouchitis, and Crohn\u27s disease of the pouch). We analyzed dietary intake by disease activity at enrollment and then compared dietary patterns among patients who remained in remission throughout the 12-month follow-up to those patients who experienced a disease relapse. We also compared dietary patterns among patients with inflammatory conditions of the pouch to the United States Department of Agriculture (USDA) recommended daily goals. RESULTS: Among 308 patients, there were no differences in dietary patterns among patients with 1 of the 4 disease states at enrollment. Additionally, among the 102 patients in remission at baseline, there were no significant differences noted among patients who went on to experience a disease flare in the 12 months after enrollment compared to those patients who remained in remission. However, patients with inflammatory conditions of the pouch demonstrated decreased intake of several food groups and macronutrients including dairy, fruits, vegetables, whole grains, and fiber when compared to USDA recommendations. CONCLUSIONS: In a prospective cohort, we demonstrated no impact of dietary patterns on disease activity. The relative deficiencies in several food groups and macronutrients among patients after IPAA indicate the potential role of targeted nutritional counseling in this population

Acclimatization of a coral-dinoflagellate mutualism at a CO2 vent

Ocean acidification caused by shifts in ocean carbonate chemistry resulting from increased atmospheric CO2 concentrations is threatening many calcifying organisms, including corals. Here we assessed autotrophy vs heterotrophy shifts in the Mediterranean zooxanthellate scleractinian coral Balanophyllia europaea acclimatized to low pH/high pCO2 conditions at a CO2 vent off Panarea Island (Italy). Dinoflagellate endosymbiont densities were higher at lowest pH Sites where changes in the distribution of distinct haplotypes of a host-specific symbiont species, Philozoon balanophyllum, were observed. An increase in symbiont C/N ratios was observed at low pH, likely as a result of increased C fixation by higher symbiont cell densities. δ13C values of the symbionts and host tissue reached similar values at the lowest pH Site, suggesting an increased influence of autotrophy with increasing acidification. Host tissue δ15N values of 0‰ strongly suggest that diazotroph N2 fixation is occurring within the coral tissue/mucus at the low pH Sites, likely explaining the decrease in host tissue C/N ratios with acidification. Overall, our findings show an acclimatization of this coral dinoflagellate mutualism through trophic adjustment and symbiont haplotype differences with increasing acidification, highlighting that some corals are capable of acclimatizing to ocean acidification predicted under end-of-century scenarios

Treatment patterns and standardized outcome assessments among patients with inflammatory conditions of the pouch in a prospective multicenter registry

BACKGROUND: Much of our understanding about the natural history of pouch-related disorders has been generated from selected populations. We designed a geographically diverse, prospective registry to study the disease course among patients with 1 of 4 inflammatory conditions of the pouch. The primary objectives in this study were to demonstrate the feasibility of a prospective pouch registry and to evaluate the predominant treatment patterns for pouch-related disorders. METHODS: We used standardized diagnostic criteria to prospectively enroll patients with acute pouchitis, chronic antibiotic-dependent pouchitis (CADP), chronic antibiotic refractory pouchitis (CARP), or Crohn\u27s disease (CD) of the pouch. We obtained detailed clinical and demographic data at the time of enrollment, along with patient-reported outcome (PRO) measures. RESULTS: We enrolled 318 patients (10% acute pouchitis, 27% CADP, 12% CARP, and 51% CD of the pouch). Among all patients, 55% were on a biologic or small molecule therapy. Patients with CD of the pouch were more likely to use several classes of therapy ( CONCLUSIONS: In a population where most patients had refractory inflammatory conditions of the pouch, we established a framework to evaluate PROs and clinical effectiveness. This infrastructure will be valuable for long-term studies of real-world effectiveness for pouch-related disorders

6-thioguanine treatment in inflammatory bowel disease: A critical appraisal by a European 6-TG working party

Recently, the suggestion to use 6-thioguanine (6-TG) as an alternative thiopurine in patients with inflammatory bowel disease (IBD) has been discarded due to reports about possible (hepato) toxicity. During meetings arranged in Vienna and Prague in 2004, European experts applying 6-TG further on in IBD patients presented data on safety and efficacy of 6-TG. After thorough evaluation of its risk-benefit ratio, the group consented that 6-TG may still be considered as a rescue drug in stringently defined indications in IBD, albeit restricted to a clinical research setting. As a potential indication for administering 6-TG, we delineated the requirement for maintenance therapy as well as intolerance and/or resistance to aminosalicylates, azathioprine, 6-mercaptopurine, methotrexate and infliximab. Furthermore, indications are preferred in which surgery is thought to be inappropriate. The standard 6-TG dosage should not exceed 25 mg daily. Routine laboratory controls are mandatory in short intervals. Liver biopsies should be performed after 6-12 months, three years and then three-yearly accompanied by gastroduodenoscopy, to monitor for potential hepatotoxicity, including nodular regenerative hyperplasia (NRH) and veno-occlusive disease (VOD). Treatment with 6-TG must be discontinued in case of overt or histologically proven hepatotoxicity. Copyright (c) 2006 S. Karger AG, Basel

The Standard Model Prediction of the Muon Anomalous Magnetic Moment

This article reviews and updates the Standard Model prediction of the muon g-2. QED, electroweak and hadronic contributions are presented, and open questions discussed. The theoretical prediction deviates from the present experimental value by 2-3 standard deviations, if e+e- annihilation data are used to evaluate the leading hadronic term.Comment: 30 pages, 8 figures. v2: Updated version to appear in J.Phys.G. Comments and references added, typo corrected in eq.(17

Optimization with partial differential equations in dieudonné-rashevsky form and conjugate problems

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/46185/1/205_2004_Article_BF00247693.pd