19 research outputs found
Graviton Spectra in String Cosmology
We propose to uncover the signature of a stringy era in the primordial
Universe by searching for a prominent peak in the relic graviton spectrum. This
feature, which in our specific model terminates an increase and
initiates an decrease, is induced during the so far overlooked
bounce of the scale factor between the collapsing deflationary era (or pre-Big
Bang) and the expanding inflationary era (or post-Big Bang). We evaluate both
analytically and numerically the frequency and the intensity of the peak and we
show that they may likely fall in the realm of the new generation of
interferometric detectors. The existence of a peak is at variance with
ordinarily monotonic (either increasing or decreasing) graviton spectra of
canonical cosmologies; its detection would therefore offer strong support to
string cosmology.Comment: 14 pages, RevTex source and 6 figures.p
The First Space-Based Gravitational-Wave Detectors
Gravitational waves provide a laboratory for general relativity and a window
to energetic astrophysical phenomena invisible with electromagnetic radiation.
Several terrestrial detectors are currently under construction, and a
space-based interferometer is envisioned for launch early next century to
detect test-mass motions induced by waves of relatively short wavelength.
Very-long-wavelength gravitational waves can be detected using the plasma in
the early Universe as test masses; the motion induced in the plasma by a wave
is imprinted onto the cosmic microwave background (CMB). While the signature of
gravitational waves on the CMB temperature fluctuations is not unique, the
polarization pattern can be used to unambiguously detect gravitational
radiation. Thus, forthcoming CMB polarization experiments, such as MAP and
Planck, will be the first space-based gravitational-wave detectors.Comment: 5 pages, 3 postscript figure
Post-intubation tracheal lacerations: Risk-stratification and treatment protocol according to morphological classification
BackgroundPost-intubation tracheal laceration (PITL) is a rare condition (0.005% of intubations). The treatment of choice has traditionally been surgical repair. Following our first report in 2010 of treatment protocol tailored to a risk-stratified morphological classification there is now clear evidence that conservative therapy represents the gold standard in the majority of patients. In this paper we aim to validate our risk-stratified treatment protocol through the largest ever reported series of patients. MethodsThis retrospective analysis is based on a prospectively collected series (2003-2020) of 62 patients with PITL, staged and treated according to our revised morphological classification. ResultsFifty-five patients with Level I (#8), II (#36) and IIIA (#11) PITL were successfully treated conservatively. Six patients with Level IIIB injury and 1 patient with Level IV underwent a surgical repair of the trachea. No mortality was reported. Bronchoscopy confirmed complete healing in all patients by day 30. Statistical analysis showed age only to be a risk factor for PITL severity. ConclusionsOur previously proposed risk-stratified morphological classification has been validated as the major tool for defining the type of treatment in PITL
Covid-19 and the role of smoking: the protocol of the multicentric prospective study COSMO-IT (COvid19 and SMOking in ITaly).
The emergency caused by Covid-19 pandemic raised interest in studying lifestyles and comorbidities as important determinants of poor Covid-19 prognosis. Data on tobacco smoking, alcohol consumption and obesity are still limited, while no data are available on the role of e-cigarettes and heated tobacco products (HTP). To clarify the role of tobacco smoking and other lifestyle habits on COVID-19 severity and progression, we designed a longitudinal observational study titled COvid19 and SMOking in ITaly (COSMO-IT). About 30 Italian hospitals in North, Centre and South of Italy joined the study. Its main aims are: 1) to quantify the role of tobacco smoking and smoking cessation on the severity and progression of COVID-19 in hospitalized patients; 2) to compare smoking prevalence and severity of the disease in relation to smoking in hospitalized COVID-19 patients versus patients treated at home; 3) to quantify the association between other lifestyle factors, such as e-cigarette and HTP use, alcohol and obesity and the risk of unfavourable COVID-19 outcomes. Socio-demographic, lifestyle and medical history information will be gathered for around 3000 hospitalized and 700-1000 home-isolated, laboratory-confirmed, COVID-19 patients. Given the current absence of a vaccine against SARS-COV-2 and the lack of a specific treatment for -COVID-19, prevention strategies are of extreme importance. This project, designed to highly contribute to the international scientific debate on the role of avoidable lifestyle habits on COVID-19 severity, will provide valuable epidemiological data in order to support important recommendations to prevent COVID-19 incidence, progression and mortality
Sruttura di alleggerimento e metodo per la realizzazione di solai
La struttura di alleggerimento per la realizzazione di solai edilizi caratterizzata dal fatto che è telescopica, comprende una pluralità di moduli (1, 2, 3) tubolari estraibili inseriti scorrevoli assialmente l’uno nell’altro. La pluralità di moduli comprende almeno un primo modulo (1) estraibile e un secondo modulo estraibile (2), ciascuno con una parete di copertura (11) sostanzialmente piana destinata, in uso, ad essere rivolta verso la caldana e una parete di fondo (13) sostanzialmente piana contrapposta alla parete di copertura (11)
CD34 (+) cell subsets and long-term culture colony-forming cells evaluated on both autologous and normal bone marrow stroma predict long-term hematopoietic engraftment in patients undergoing autologous peripheral blood stem cell transplantation.
The aim of this study was to evaluate which CD34(+) cell subset contained in leukapheresis products could be regarded as the most predictive of long-term hematopoietic recovery after autologous peripheral blood stem cell transplantation (auto-PBSCT).
MATERIALS AND METHODS:
Based on data from 34 patients with hematologic malignancies, doses of CD34(+) cells and CD34(+) cell subsets, defined by the expression of HLA-DR, CD38, CD117 (c-kit/R), CD123 (alpha subunit of IL-3/R), CD133 (AC133), and CD90 (Thy-1) antigens, were correlated with the number of short-term (i.e., colony-forming cells [CFC]) and long-term culture CFC (LTC-CFC) (generated at week 5 of culture) and with the kinetics of hematopoietic engraftment following auto-PBSCT. The capacity of autologous stroma (AS), normal human bone marrow stroma, and M2-10B4 murine cell line to sustain CD34(+) cell growth was comparatively evaluated in the LTC assay.
RESULTS:
Our data demonstrated that some of the most primitive progenitor subsets (CD34(+)CD117(-)HLA-DR(-), and CD34(+)CD38(+)HLA-DR(-)) showed the strongest correlation with LTC-CFC numbers generated within the AS, whereas no significant correlation was noted using normal bone marrow stroma. Multivariate analysis showed that the only CD34 cell subset independently associated with long-term (3 to 6 months) platelet engraftment after auto-bone marrow transplantation was the CD34(+)CD117(-)HLA-DR(-) phenotype; long-term erythrocyte engraftment was correlated with CD34(+)CD38(+)HLA-DR(-) cell content. The latter further influenced platelet engraftment in the first 3 months after auto-PBSCT. The most predictive parameters for neutrophil engraftment were CD34(+)CD38(+)HLA-DR(-) cell subtype and the total LTC-CFC quantity infused.
CONCLUSIONS:
These data further support the hypothesis that the type of stromal feeders influences the frequency of LTC-CFC, possibly because they differ in their ability to interact with distinct subsets of hematopoietic stem cells. Furthermore, as the use of AS in LTC assay can mimic in vitro the human bone marrow microenvironment, it can be speculated that this culture system could be a useful means to study the kinetics of recovery of bone marrow stroma following chemotherapy and PBSCT. From these results, it can be concluded that some CD34(+) cell subsets appear to be more reliable predictors of long-term hematopoietic recovery rates than total CD34(+) cell quantit
Association Analysis of Noncoding Variants in Neuroligins 3 and 4X Genes with Autism Spectrum Disorder in an Italian Cohort
Since involved in synaptic transmission and located on X-chromosome, neuroligins 3 and 4X have been studied as good positional and functional candidate genes for autism spectrum disorder pathogenesis, although contradictory results have been reported. Here, we performed a case-control study to assess the association between noncoding genetic variants in NLGN3 and NLGN4X genes and autism, in an Italian cohort of 202 autistic children analyzed by high-resolution melting. The results were first compared with data from 379 European healthy controls (1000 Genomes Project) and then with those from 1061 Italian controls genotyped by Illumina single nucleotide polymorphism (SNP) array 1M-duo. Statistical evaluations were performed using Plink v1.07, with the Omnibus multiple loci approach. According to both the European and the Italian control groups, a 6-marker haplotype on NLGN4X (rs6638575(G), rs3810688(T), rs3810687(G), rs3810686(C), rs5916269(G), rs1882260(T)) was associated with autism (odd ratio = 3.58, p-value = 2.58 × 10(-6) for the European controls; odds ratio = 2.42, p-value = 6.33 × 10(-3) for the Italian controls). Furthermore, several haplotype blocks at 5-, 4-, 3-, and 2-, including the first 5, 4, 3, and 2 SNPs, respectively, showed a similar association with autism. We provide evidence that noncoding polymorphisms on NLGN4X may be associated to autism, suggesting the key role of NLGN4X in autism pathophysiology and in its male prevalence
Effect of normalization of fasting glucose by intensified insulin therapy and influence of eNOS polymorphisms on the incidence of restenosis after peripheral angioplasty in patients with type 2 diabetes: A randomized, open-label clinical trial
Primary objective was to evaluate whether an intensified insulin therapy (IIT) incorporating the target of normal fasting glucose and HbA1c levels could halve the incidence of restenosis/amputation/SCA/death at 6 months after peripheral angioplasty compared with standard care (SC) in patients with type 2 diabetes (DMT2) affected by critical limb ischemia (CLI). Forty-six consecutive patients with DMT2 and CLI were randomly assigned to a parallel, open-label study with IIT (basal-bolus glulisine + glargine administrations) or SC (glargine administration + oral antidiabetic drugs). A SNP of eNOS (rs753482-A>C) and circulating CD34+ and CD34+KDR + progenitor cells were determined. At the end of the study, although HbA1c levels were lower in IIT than in SC (6.9 ± 1.3 % vs. 7.6 ± 1.2 %, p C SNP) and circulating endothelial progenitor cells. © 2012 Springer-Verlag