625 research outputs found
Decomposition of leaf litter of Phillyrea angustifolia L. and mixed aboveground litter of herbaceous species from a mediterranean maquis.
Periodogram and likelihood periodicity search in the SNO solar neutrino data
In this work a detailed spectral analysis for periodicity search of the time
series of the 8B solar neutrino flux released by the SNO Collaboration is
presented. The data have been publicly released with truncation of the event
times to the unit of day (1 day binning); they are thus suited to undergo the
traditional Lomb-Scargle analysis for periodicity investigation, as well as an
extension of such a method based on a likelihood approach. The results of the
analysis presented here confirm the absence of modulation signatures in the SNO
data. For completeness, a more refined "1 day binned" likelihood is also
illustrated, which approximates the unbinned likelihood methodology, based upon
the availability of the full time information, adopted by the SNO
collaboration. Finally, this work is completed with two different joint
analyses of the SNO and Super-Kamiokande data, respectively, over the common
and the entire data taking periods. While both analyses reinforce the case of
the constancy of the neutrino flux, the latter in addition provides evidence of
the detection at the 99.7% confidence level of the annual modulation spectral
line due to the Earth's orbit eccentricity around the SunComment: 27 pages, 29 figures. Joint periodicity analysis of the SNO and
Super-Kamiokande data added. Accepted for publication on Phys. Rev.
The AGMA1 poly(amidoamine) inhibits the infectivity of herpes simplex virus in cell lines, in human cervicovaginal histocultures, and in vaginally infected mice
The development of topical microbicides is a valid approach to protect the genital mucosa from sexually transmitted infections that cannot be contained with effective vaccination, like HSV and HIV infections. A suitable target of microbicides is the interaction between viral proteins and cell surface heparan sulfate proteoglycans (HSPGs). AGMA1 is a prevailingly cationic agmatine-containing polyamidoamine polymer previously shown to inhibit HSPGs dependent viruses, including HSV-1, HSV-2, and HPV-16. The aim of this study was to elucidate the mechanism of action of AGMA1 against HSV infection and assess its antiviral efficacy and biocompatibility in preclinical models. The results show AGMA1 to be a non-toxic inhibitor of HSV infectivity in cell cultures and human cervicovaginal histocultures. Moreover, it significantly reduced the burden of infection of HSV-2 genital infection in mice. The investigation of the mechanism of action revealed that AGMA1 reduces cells susceptibility to virus infection by binding to cell surface HSPGs thereby preventing HSV attachment. This study indicates that AGMA1 is a promising candidate for the development of a topical microbicide to prevent sexually transmitted HSV infections
Surgical therapy for ischemic heart failure: Single-center experience with surgical anterior ventricular restoration
ObjectivesOur objectives were (1) to report operative and long-term mortality in patients submitted to anterior surgical ventricular restoration, (2) to report changes in clinical and cardiac status induced by surgical ventricular restoration, and (3) to report predictors of death in a large cohort of patients operated on at San Donato Hospital, Milan, Italy.MethodsA total of 1161 consecutive patients (83% men, 62 ± 10 years) had anterior surgical ventricular restoration with or without coronary artery bypass grafting and with or without mitral repair/replacement. A complete echocardiographic study was performed in 488 of 1161 patients operated on between January 1998 and October 2005 (study group). The indication for surgery was heart failure in 60% of patients, angina, and/or a combination of the two.ResultsThirty-day cardiac mortality was 4.7% (55/1161) in the overall group and 4.9% (24/488) in the study group. Determinants of hospital mortality were mitral valve regurgitation and need for a mitral valve repair/replacement. Mitral regurgitation (>2+) associated with a New York Heart Association class greater than II and with diastolic dysfunction (early-to-late diastolic filling pressure >2) further increases mortality risk. Global systolic function improved postoperatively: ejection fraction improved from 33% ± 9% to 40% ± 10% (P < .001); end-diastolic and end-systolic volumes decreased from 211 ± 73 to 142 ± 50 and 145 ± 64 to 88 ± 40 mL, respectively (P < .001) early after surgery. New York Heart Association functional class improved from 2.7 ± 0.9 to 1.6 ± 0.7 (P < .001) late after surgery. Long-term survival in the overall population was 63% at 120 months.ConclusionsSurgical ventricular restoration for ischemic heart failure reduces ventricular volumes, improves cardiac function and functional status, carries an acceptable operative mortality, and results in good long-term survival. Predictors of operative mortality are mitral regurgitation of 2+ or more, New York Heart Association class greater than II, and diastolic dysfunction (early-to-late diastolic filling pressure >2)
Theoretical modeling of coagulation management with therapeutic plasma or prothrombin complex concentrate
Comparison of fibrin-based clot elasticity parameters measured by free oscillation rheometry (ReoRox (R)) versus thromboelastometry (ROTEM (R))
Background. Whole blood viscoelastic tests such as the fibrin-based thromboelastometry (ROTEM (R)) test FIBTEM are increasingly used in the perioperative setting to quickly identify deficits in fibrin quality, and to guide hemostatic therapy. The recently developed FibScreen2 test of the ReoRox (R) method, based on free oscillation rheometry, also provides an evaluation of fibrin clot quality. To date, little information is available on the performance of this test in hemodiluted blood, by comparison to FIBTEM. Methods. Whole blood samples from eight healthy volunteers were analyzed using FIBTEM and Fibscreen2. Native and diluted (to 33% and 50% using saline, gelatin or hydroxyethyl starch [HES]) samples were analyzed. Clot strength parameters, including FIBTEM maximum clot firmness (MCF), FIBTEM maximum clot elasticity (MCE) and Fibscreen2 maximum elasticity (G'max), were measured. Results. In repeatedly measured samples from two volunteers, FIBTEM MCF and Fibscreen2 G'max revealed a coefficient of variation (CV) of 5.3 vs. 16.3% and 5.6 vs. 31.7% for each volunteer, respectively. Hemodilution decreased clot strength. Both Fibscreen2 G'max and FIBTEM parameters decreased proportionally to the dilution ratio when saline was used. The observed reductions in FIBTEM and Fibscreen2 parameters were more severe in samples diluted with gelatin and HES, compared to saline. Finally, a regression analysis between FIBTEM MCE and Fibscreen2 G'max revealed a poor goodness of fit (r(2) = 0.37, p < 0.0001). Conclusions. ReoRox (R) Fibscreen2 test has a high coefficient of variation, and its application in various hemodilution conditions showed limited comparability with the ROTEM (R) FIBTEM test
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