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Selected AbstractsDetermination of the weaker phase in the pitting corrosion of non-standard low-Ni high-Mn-N duplex stainless steelsMATERIALS AND CORROSION/WERKSTOFFE UND KORROSION, Issue 2 2004R. Merello Abstract In this paper, the use of Energy Dispersive Spectrometry (EDS) is proposed to determine the partition coefficients of the elements of a new family of duplex stainless steels that are characterized by having low contents of nickel, together with high levels of manganese and nitrogen. From the values of the partition coefficients, the chemical compositions of the constituting phases have been determined, in order subsequently to calculate the value of the Pitting Resistance Equivalent Number (PREN) of each phase. The proposition put forward in this study is that the phase having the lower PREN determines the pitting corrosion behaviour of these types of steels. Results obtained by means of optical and scanning electron microscopy have provided confirmation that the pitting corrosion behaviour of these new materials gets determined by the resistance of the weaker phase and consequently by the phase having the lower PREN value. Lastly it has been proved possible to determine the existence of an exponential relationship between the alloys pitting potential (Ep) and the weaker phase PREN; this can be utilized for the low-nickel duplex stainless steels design in which the pitting corrosion resistance is controlled. [source] Lux vs. wavelength in light treatment of Seasonal Affective DisorderACTA PSYCHIATRICA SCANDINAVICA, Issue 3 2009J. L. Anderson Objective:, Published dosing guidelines for treatment of Seasonal Affective Disorder (SAD) refer to photopic lux, which is not appropriate for short-wavelength light. Short wavelengths are most potent for many non-visual responses to light. If SAD therapy were similarly mediated, standards utilizing lux risk overestimating necessary dose. We investigated antidepressant responses to light using two light-emitting diode (LED) sources, each emitting substantial short-wavelength light, but <2500 lux. Method:, A randomized, double-blind trial investigated 3-week 45 min/day out-patient treatment with blue-appearing (goLITE®) or blue-enriched white-appearing light in 18 moderately-depressed adults (12F, 49.1 ± 9.5 years). Equivalent numbers of photons within the short-wavelength range were emitted, but the white source emitted twice as many photons overall and seven-fold more lux. Results:, Depression ratings (SIGH-ADS; http://www.cet.org) decrease averaged 82% (SD = 17%) from baseline (P < 0.0001) in both white- and blue-light groups. Both sources were well tolerated. Conclusion:, Short-wavelength LED light sources may be effective in SAD treatment at fewer lux than traditional fluorescent sources. [source] REDUCING INCIDENTAL MORTALITY OF FRANCISCANA DOLPHIN PONTOPORIA BLAINVILLEI WITH ACOUSTIC WARNING DEVICES ATTACHED TO FISHING NETSMARINE MAMMAL SCIENCE, Issue 4 2002P. Bordino Abstract We conducted a double blind experiment in an artisanal gillnet fishery in Argentina to determine the effectiveness of acoustic deterrents (pingers) at reducing bycatch of the Franciscana dolphin (Pontoporia blainvillei). The fishery was conducted by small inflatable and fiberglass vessels operating between 0.5 and 7 krn from the coast. Each vessel carried an independent observer who was rotated from vessel to vessel throughout the course of the experiment. Information on the number of dolphins captured, geographic position, depth, configuration of fishing gear, soak time, biomass of fish caught, and sea lion predation in a string/net producing any damage was recorded. Equivalent numbers of active and silent pingers were used during the experiment. A total of 45 dolphins were caught in the silent nets, and seven were caught in the active pinger nets, demonstrating a highly significant reduction in bycatch for this species. However, sea-lions (Otaria flavescens) damaged the fish in active pinger nets significantly more than silent nets, and the damage increased over the course of the experiment. Although pingers show promise as a management tool for this species, pinniped depredation suggests that higher pinger frequencies will be needed to avoid a "dinner bell" effect. [source] Ground motion duration effects on nonlinear seismic responseEARTHQUAKE ENGINEERING AND STRUCTURAL DYNAMICS, Issue 1 2006Iunio Iervolino Abstract The study presented in this paper addresses the question of which nonlinear demand measures are sensitive to ground motion duration by statistical analyses of several case studies. A number of single degree of freedom (SDOF) structures were selected considering: (1) four oscillation periods; (2) three evolutionary and non-evolutionary hysteretic behaviours; (3) two target ductility levels. Effects of duration are investigated, by nonlinear dynamic analysis, with respect to six different demand indices ranging from displacement ductility ratio to equivalent number of cycles. Input is made of six real accelerogram sets representing three specific duration scenarios (small, moderate and large duration). For all considered demand quantities time-history results are formally compared by statistical hypothesis test to asses the difference, if any, in the demand concerning different scenarios. Incremental dynamic analysis curves are used to evaluate duration effect as function of ground motion intensity (e.g. spectral acceleration corresponding to the SDOF's oscillation period). Duration impact on structural failure probability is evaluated by fragility curves. The results lead to the conclusion that duration content of ground motion is statistically insignificant to displacement ductility and cyclic ductility demand. The conclusions hold regardless of SDOF's period and hysteretic relationship investigated. Copyright © 2005 John Wiley & Sons, Ltd. [source] Basis functions for the consistent and accurate representation of surface mass loadingGEOPHYSICAL JOURNAL INTERNATIONAL, Issue 1 2007Peter J. Clarke SUMMARY Inversion of geodetic site displacement data to infer surface mass loads has previously been demonstrated using a spherical harmonic representation of the load. This method suffers from the continent-rich, ocean-poor distribution of geodetic data, coupled with the predominance of the continental load (water storage and atmospheric pressure) compared with the ocean bottom pressure (including the inverse barometer response). Finer-scale inversion becomes unstable due to the rapidly increasing number of parameters which are poorly constrained by the data geometry. Several approaches have previously been tried to mitigate this, including the adoption of constraints over the oceanic domain derived from ocean circulation models, the use of smoothness constraints for the oceanic load, and the incorporation of GRACE gravity field data. However, these methods do not provide appropriate treatment of mass conservation and of the ocean's equilibrium-tide response to the total gravitational field. Instead, we propose a modified set of basis functions as an alternative to standard spherical harmonics. Our basis functions allow variability of the load over continental regions, but impose global mass conservation and equilibrium tidal behaviour of the oceans. We test our basis functions first for the efficiency of fitting to realistic modelled surface loads, and then for accuracy of the estimates of the inferred load compared with the known model load, using synthetic geodetic displacements with real GPS network geometry. Compared to standard spherical harmonics, our basis functions yield a better fit to the model loads over the period 1997,2005, for an equivalent number of parameters, and provide a more accurate and stable fit using the synthetic geodetic displacements. In particular, recovery of the low-degree coefficients is greatly improved. Using a nine-parameter fit we are able to model 58 per cent of the variance in the synthetic degree-1 zonal coefficient time-series, 38,41 per cent of the degree-1 non-zonal coefficients, and 80 per cent of the degree-2 zonal coefficient. An equivalent spherical harmonic estimate truncated at degree 2 is able to model the degree-1 zonal coefficient similarly (56 per cent of variance), but only models 59 per cent of the degree-2 zonal coefficient variance and is unable to model the degree-1 non-zonal coefficients. [source] IL-10 and IL-4 regulate type-I and type-II IL-1 receptors expression on IL-1,-activated mouse primary astrocytesJOURNAL OF NEUROCHEMISTRY, Issue 4 2001F. Pousset When activated by its ligand, the interleukin receptor type I (IL-1RI) transduces signals in cooperation with the IL-1 receptor accessory protein (IL-1RacP). In contrast, IL-1RII functions as a decoy receptor without participating in IL-1 signalling. Brain astrocytes are cellular targets of IL-1 and play a pivotal role in brain responses to inflammation. The regulation of IL-1 receptors on astrocytes by anti-inflammatory cytokines such as IL-4 and IL-10 has not been studied, despite its importance for understanding the way these cells respond to IL-1. Using RT-PCR, we first showed that the expression of IL-1RI and IL-1RII, but not IL-1RacP, mRNAs are up-regulated by IL-1, in a time-dependent manner. Using a radioligand binding technique, we then showed that astrocytes display an equivalent number of IL-1RI and IL-1RII. IL-1, decreases the number of IL-1RI binding sites, whereas it increases those of IL-1RII. IL-4 and IL-10 both up-regulate IL-1RII IL-1,-induced, but only IL-4 does so for IL-1RI. At the protein level, IL-4 and IL-10 dramatically reverse the ability of IL-1, to inhibit expression of IL-1RI but neither affects the ability of IL-1, to enhance the number of IL-1RII. Collectively, these results establish the existence of receptor cross-talk between pro- and anti-inflammatory cytokines on a critical type of cell that regulates inflammatory events in the brain. [source] Human Islets Derived From Donors After Cardiac Death Are Fully BiofunctionalAMERICAN JOURNAL OF TRANSPLANTATION, Issue 10 2007M. Zhao Islets from brain-dead donors (BDDs) are being used in the treatment of Type 1 diabetes. However, both donor numbers and islet survival are limited. We explored the clinical potential for islets from non-heart-beating donors (NHBDs), who have lower circulating cytokines, by comparing islets from 10 NHBDs against 12 identically-isolated islets from BDDs over the same time period. The quantity and quality of islets from NHBDs was good. NHBD yielded ,12.6% more islets than those of BDDs (505 000 ± 84 230 vs. 400 970 ± 172 430 islet equivalent number [IEQ]/pancreas, p = 0.01) with comparable viability. ATP and GTP contents were lower (6.026 ± 3.076 vs. 18.105 ± 7.8 nM/mg protein, p = 0.01 and 1.52 ± 0.87 vs. 3.378 ± 0.83 nM/mg protein, p = 0.04) and correlated negatively to warm ischemia time (R2= 0.8022 and R2= 0.7996, respectively). Islets from NHBDs took longer to control hyperglycemia in diabetic mice, but were equally able to sustain euglycemia. With a warm ischemia time (WIT) of ,25 min, islets from NHBDs are at least as competent as islets from BDDs and should be suitable for clinical use. [source] The percentage of prostate needle biopsy cores with carcinoma from the more involved side of the biopsy as a predictor of prostate specific antigen recurrence after radical prostatectomy,,CANCER, Issue 11 2003Results from the Shared Equal Access Regional Cancer Hospital (SEARCH) database Abstract BACKGROUND The authors previously found that, although the total percentage of prostate needle biopsy cores with carcinoma was a significant predictor of prostate specific antigen (PSA) failure among men undergoing radical prostatectomy (RP), there was a trend toward a lower risk of recurrence in patients with positive bilateral biopsies, suggesting that high-volume, unilateral disease was a worse predictor of outcome than an equivalent number of positive cores distributed over two lobes. In the current study, the authors sought to compare the total percentage of cores with carcinoma directly with the percentage of cores from the more involved or dominant side of the prostate with carcinoma for their ability to predict outcome among men who underwent RP. METHODS A retrospective survey of 535 patients from the Shared Equal Access Regional Cancer Hospital database who underwent RP at 4 different equal-access medical centers between 1988 and 2002 was undertaken. The total percentage of cores positive was compared with the percentage of cores positive from the dominant and nondominant sides for their ability to predict biochemical recurrence after RP. The best predictor then was compared with the standard clinical variables PSA, biopsy Gleason score, and clinical stage in terms of ability to predict time to PSA recurrence after RP using multivariate analysis. RESULTS The adverse pathologic features of positive surgical margins and extracapsular extension were significantly more likely to be ipsilateral to the dominant side on the prostate biopsy. The percentage of cores positive from the dominant side provided slightly better prediction (concordance index [C] = 0.636) for PSA failure than the total percentage of cores positive (C = 0.596) and markedly better than the percentage of cores from the nondominant side (C = 0.509). Cutoff points for percentage of cores positive from the dominant side were identified (< 34%, 34,67%, and > 67%) that provided significant risk stratification for PSA failure (P < 0.001). On multivariate analysis, the percentage of cores positive from the dominant side was the strongest independent predictor of PSA recurrence (P < 0.001). Biopsy Gleason score (P = 0.017) also was a significant, independent predictor of recurrence. There was a trend, which did not reach statistical significance, toward an association between greater PSA values and biochemical failure (P = 0.052). Combining the PSA level, biopsy Gleason score, and percentage of cores positive from the dominant side of the prostate resulted in a model that provided a high degree of prediction for PSA failure (C = 0.671). CONCLUSIONS The percentage of cores positive from the dominant side of the prostate was a slightly better predictor of PSA recurrence than was the total percentage of cores positive. Using the percentage of cores from the dominant side along with the PSA level and the biopsy Gleason score provided significant risk stratification for PSA failure. Cancer 2003. Published 2003 by the American Cancer Society. [source] Which Controls the Depolymerization of Cellulose in Ionic Liquids: The Solid Acid Catalyst or Cellulose?CHEMSUSCHEM CHEMISTRY AND SUSTAINABILITY, ENERGY & MATERIALS, Issue 2 2010Roberto Rinaldi Dr. Abstract Cellulose is a renewable and widely available feedstock. It is a biopolymer that is typically found in wood, straw, grass, municipal solid waste, and crop residues. Its use as raw material for biofuel production opens up the possibility of sustainable biorefinery schemes that do not compete with food supply. Tapping into this feedstock for the production of biofuels and chemicals requires,as the first-step,its depolymerization or its hydrolysis into intermediates that are more susceptible to chemical and/or biological transformations. We have shown earlier that solid acids selectively catalyze the depolymerization of cellulose solubilized in 1-butyl-3-methylimidazolium chloride (BMIMCl) at 100,°C. Here, we address the factors responsible for the control of this reaction. Both cellulose and solid acid catalysts have distinct and important roles in the process. Describing the depolymerization of cellulose by the equivalent number of scissions occurring in the cellulosic chains allows a direct correlation between the product yields and the extent of the polymer breakdown. The effect of the acid strength on the depolymerization of cellulose is discussed in detail. Practical aspects of the reaction, concerning the homogeneous nature of the catalysis in spite of the use of a solid acid catalyst, are thoroughly addressed. The effect of impurities present in the imidazolium-based ionic liquids on the reaction performance, the suitability of different ionic liquids as solvents, and the recyclability of Amberlyst 15DRY and BMIMCl are also presented. [source] Therapeutic benefit of pentostatin in severe IL-10,/, ColitisINFLAMMATORY BOWEL DISEASES, Issue 7 2008Jeffrey B. Brown MD Abstract Background: Pentostatin, an adenosine deaminase (ADA) inhibitor, is a purine antimetabolite used for the treatment of leukemias. ADA inhibition blunts expansion of proliferating lymphocytes and increases adenosine release, a potent anti-inflammatory molecule. Human inflammatory bowel disease (IBD) is driven by expansion of effector T cells (Teff) that overwhelm reulatory T cells (Treg) and propagate innate immune reponses. Here we study the therapeutic benefits of ADA inhibition to impair Teff cell expansion and reduce inflammatory cytokine release in IL-10-deficient (IL-10 -/- ) mice. Methods: Colitis was induced in IL-10 -/- mice by administering piroxicam for two weeks. Mice were treated with daily pentostatin or phosphate-buffered saline for 1 week and effects on tissue inflammation, lymphocyte numbers and cytokine production examined. Results: Pentostatin reduced inflammation by >50% and nearly normalized serum amyloid A levels. Lymphocyte expansions in the colon and mesenteric lymph node (MLN) (3.5-fold and >5-fold respectively) dropped by >50-90%. Pro-inflammatory factors in the colon and MLN (IL-1,, IFN-,, IL-6, CXCL10, TNF) dropped whereas FoxP3 and TGF-, were unchanged. Reductions in cytokine production from equivalent numbers of T cells from pentostatin-treated mice after in vitro (36h) or in vivo (3h) activation suggested anti-inflammatory effects of pentostatin independent of lymphodepletion contributed to its therapeutic benefit. Analysis of mucosal lymphocyte subsets suggested pentostatin reduced numbers of effector CD4+ CD69+ T cells, while sparing CD4+ CD62L+ T cells. Conclusions: Pentostatin dosages that avoid severe lymphocyte depletion effectively treat colitis by impairing Teff cell expansion and reducing pro-inflammatory cytokine production while preserving regulatory Treg populations and function. (Inflamm Bowel Dis 2008) [source] Long-lasting coexpression of nestin and glial fibrillary acidic protein in primary cultures of astroglial cells with a major participation of nestin+/GFAP, cells in cell proliferationJOURNAL OF NEUROSCIENCE RESEARCH, Issue 8 2006Solène Sergent-Tanguy Abstract Nestin, a currently used marker of neural stem cells, is transiently coexpressed with glial fibrillary acidic protein (GFAP) during development and is induced in reactive astrocytes following brain injury. Nestin expression has also been found in cultures of astroglial cells, but little is known about the fate and the mitotic activity of nestin-expressing cells in this in vitro model. The present study reveals a long-lasting expression of nestin in primary cultures of astroglial cells derived from the rat brain. Over 70% of the cells were nestin+ at 12 weeks, with a large majority coexpressing the GFAP astrocytic marker. Time-course analyses supported a transition from a nestin+/GFAP, to a nestin+/GFAP+ phenotype over time, which was further increased by cell cycle arrest. Interestingly, double staining with Ki67 revealed that over 90% of cycling cells were nestin+ whereas only 28% were GFAP+ in a population consisting of almost equivalent numbers of nestin+ and GFAP+ cells. These observations indicated that nestin+/GFAP, cells are actively engaged in mitotic activity, even after 2 weeks in vitro. Part of these cells might have retained properties of neural stem cells, insofar as 10% of cells in a primary culture of glial cells were able to generate neurospheres that gave rise to both neurons and astrocytes. Further studies will be necessary to characterize fully the proliferating cells in primary cultures of glial cells, but our present results reveal a major contribution of the nestin+/GFAP, cells to the increase in the number of astrocytes, even though nestin+/GFAP+ cells proliferate also. © 2006 Wiley-Liss, Inc. [source] CCR5 Is Required for Regulation of Alloreactive T-Cell Responses to Single Class II MHC-Mismatched Murine Cardiac GraftsAMERICAN JOURNAL OF TRANSPLANTATION, Issue 10 2009T. Nozaki The effector CD4 T-cell response in wild-type C57BL/6 recipients of single class II MHC-disparate B6.H-2bm12 cardiac allografts is restricted by CD4+CD25+ regulatory T cells (Tregs) resulting in long-term allograft survival. To investigate the role chemokine receptors might play in Treg function, this study tested the requirement for CCR5 on Tregs to suppress the alloimmune response in C57BL/6 recipients of B6.H-2bm12 cardiac allografts. In contrast to the long-term survival of B6.H-2bm12 allografts in wild-type recipients (>100 days), the allografts were acutely rejected within 25 days in CCR5,/, recipients with intense infiltration of CD4 T cells. Numbers and duration of donor-reactive CD4 T cells producing IFN-, and IL-4 were markedly increased in spleens of B6.CCR5,/, versus wild-type recipients. Wild-type and B6.CCR5,/, mice had equivalent numbers of splenic FoxP3+ Tregs before and following transplantation, and these Tregs were equivalently suppressive in vitro. However, diminished numbers of FoxP3+ Tregs infiltrated B6.H-2bm12 allografts in B6.CCR5,/, recipients. Adoptive transfer of wild-type, but not CCR5-deficient, CD4+CD25+ Tregs to CCR5,/, recipients restored long-term survival of B6.H-2bm12 cardiac grafts. Collectively, these results indicate that CCR5 expression is required for the regulatory functions of Tregs that restrict alloreactive CD4 T-cell responses to single class II MHC-mismatched cardiac allografts. [source] | |||||||||||||