On the Average Comoving Number Density of Halos

I compare the numerical multiplicity function given in Yahagi, Nagashima & Yoshii (2004) with the theoretical multiplicity function obtained by means of the excursion set model and an improved version of the barrier shape obtained in Del Popolo & Gambera (1998), which implicitly takes account of total angular momentum acquired by the proto-structure during evolution and of a non-zero cosmological constant. I show that the multiplicity function obtained in the present paper, is in better agreement with Yahagi, Nagashima & Yoshii (2004) simulations than other previous models (Sheth & Tormen 1999; Sheth, Mo & Tormen 2001; Sheth & Tormen 2002; Jenkins et al. 2001) and that differently from some previous multiplicity function models (Jenkins et al. 2001; Yahagi, Nagashima & Yoshii 2004) it was obtained from a sound theoretical background

Drivers of fish choice: an exploratory analysis in Mediterranean countries

Fish is an important source of healthy proteins and an important economic sector in Mediterranean countries. Despite the wealth of knowledge acquired in Western countries, a gap has been found in studies in developing countries, as in the Mediterranean southern shore. Therefore, we aimed to investigate consumers’ perceptions of finfish attributes, with qualitative tools as focus groups, given the exploratory nature of the research. The focus groups have been held in Italy, Lebanon, Spain, and Tunisia; in each country, one was held in seaside areas and one in inland areas, in order to control for the availability of fish that shapes consumers’ evaluations and expectations. The focus groups have been analysed through content and semantic analyses. Results of the study yielded main themes recurring in the discussions that have been categorized along such dimensions: (1) definition of fish products; (2) context; (3) search attributes; (4) experience attributes; and (5) credence attributes. Among attributes, the ones mostly guiding consumers’ choices seem to be freshness and fish species, which are used as proxies for quality and sensory attributes. Most of the respondents preferred delicate white fish, while some exceptions were found in Tunisian respondents preferring blue fish and they also were the only ones who were not looking for convenient and already cleaned products. Trust also represented a critical element in guiding the decisions of consumers: with a lack of trust, consumers deviate from preferring local products, as noticeable especially in Lebanese respondents’ opinions. Credence attributes such as animal welfare and sustainability received a minor attention from all the respondents

Spontaneous creation of Kibble-Zurek solitons in a Bose-Einstein condensate

When a system crosses a second-order phase transition on a finite timescale, spontaneous symmetry breaking can cause the development of domains with independent order parameters, which then grow and approach each other creating boundary defects. This is known as Kibble-Zurek mechanism. Originally introduced in cosmology, it applies both to classical and quantum phase transitions, in a wide variety of physical systems. Here we report on the spontaneous creation of solitons in Bose-Einstein condensates via the Kibble-Zurek mechanism. We measure the power-law dependence of defects number with the quench time, and provide a check of the Kibble-Zurek scaling with the sonic horizon. These results provide a promising test bed for the determination of critical exponents in Bose-Einstein condensates.Comment: 7 pages, 4 figure

Periodontitis and Hypertension: Is the Association Causal?

High blood pressure (BP) and periodontitis are two highly prevalent conditions worldwide with a significant impact on cardiovascular disease (CVD) complications. Poor periodontal health is associated with increased prevalence of hypertension and may have an influence on BP control. Risk factors such as older age, male gender, non-Caucasian ethnicity, smoking, overweight/obesity, diabetes, low socioeconomic status, and poor education have been considered the common denominators underpinning this relationship. However, recent evidence indicates that the association between periodontitis and hypertension is independent of common risk factors and may in fact be causal in nature. Low-grade systemic inflammation and redox imbalance, in particular, represent the major underlying mechanisms in this relationship. Neutrophil dysfunction, imbalance in T cell subtypes, oral-gut dysbiosis, hyperexpression of proinflammatory genes, and increased sympathetic outflow are some of the pathogenetic events involved. In addition, novel findings indicate that common genetic bases might shape the immune profile towards this clinical phenotype, offering a rationale for potential therapeutic and prevention strategies of public health interest. This review summarizes recent advances, knowledge gaps and possible future directions in the field

Young giants of intermediate mass: Evidence of rotation and mixing

Context. In the search of a sample of metal-poor bright giants using Strömgren photometry, we serendipitously found a sample of 26 young (ages younger than 1 Gyr) metal-rich giants, some of which have high rotational velocities. Aims. We determined the chemical composition and rotational velocities of these stars in order to compare them with predictions from stellar evolution models. These stars where of spectral type A to B when on the main sequence, and we therefore wished to compare their abundance pattern to that of main-sequence A and B stars. Methods. Stellar masses were derived by comparison of the position of the stars in the colour-magnitude diagram with theoretical evolutionary tracks. These masses, together with Gaia photometry and parallaxes, were used to derive the stellar parameters. We used spectrum synthesis and model atmospheres to determine chemical abundances for 16 elements (C, N, O, Mg, Al, Ca, Fe, Sr, Y, Ba, La, Ce, Pr, Nd, Sm, and Eu) and rotational velocities. Results. The age-metallicity degeneracy can affect photometric metallicity calibrations. We identify 15 stars as likely binary stars. All stars are in prograde motion around the Galactic centre and belong to the thin-disc population. All but one of the sample stars present low [C/Fe] and high [N/Fe] ratios together with constant [(C+N+O)/Fe], suggesting that they have undergone CNO processing and first dredge-up. The observed rotational velocities are in line with theoretical predictions of the evolution of rotating stars

Face Mask Use in the Community for Reducing the Spread of COVID-19: A Systematic Review.

Background: Evidence is needed on the effectiveness of wearing face masks in the community to prevent SARS-CoV-2 transmission. Methods: Systematic review and meta-analysis to investigate the efficacy and effectiveness of face mask use in a community setting and to predict the effectiveness of wearing a mask. We searched MEDLINE, EMBASE, SCISEARCH, The Cochrane Library, and pre-prints from inception to 22 April 2020 without restriction by language. We rated the certainty of evidence according to Cochrane and GRADE approach. Findings: Our search identified 35 studies, including three randomized controlled trials (RCTs) (4,017 patients), 10 comparative studies (18,984 patients), 13 predictive models, nine laboratory experimental studies. For reducing infection rates, the estimates of cluster-RCTs were in favor of wearing face masks vs. no mask, but not at statistically significant levels (adjusted OR 0.90, 95% CI 0.78–1.05). Similar findings were reported in observational studies. Mathematical models indicated an important decrease in mortality when the population mask coverage is near-universal, regardless of mask efficacy. In the best-case scenario, when the mask efficacy is at 95%, the R0 can fall to 0.99 from an initial value of 16.90. Levels of mask filtration efficiency were heterogeneous, depending on the materials used (surgical mask: 45–97%). One laboratory study suggested a viral load reduction of 0.25 (95% CI 0.09–0.67) in favor of mask vs. no mask. Interpretation: The findings of this systematic review and meta-analysis support the use of face masks in a community setting. Robust randomized trials on face mask effectiveness are needed to inform evidence-based policies. PROSPERO registration: CRD42020184963

Face Mask Use in the Community for Reducing the Spread of COVID-19: A Systematic Review

Background: Evidence is needed on the effectiveness of wearing face masks in the community to prevent SARS-CoV-2 transmission. / Methods: Systematic review and meta-analysis to investigate the efficacy and effectiveness of face mask use in a community setting and to predict the effectiveness of wearing a mask. We searched MEDLINE, EMBASE, SCISEARCH, The Cochrane Library, and pre-prints from inception to 22 April 2020 without restriction by language. We rated the certainty of evidence according to Cochrane and GRADE approach. / Findings: Our search identified 35 studies, including three randomized controlled trials (RCTs) (4,017 patients), 10 comparative studies (18,984 patients), 13 predictive models, nine laboratory experimental studies. For reducing infection rates, the estimates of cluster-RCTs were in favor of wearing face masks vs. no mask, but not at statistically significant levels (adjusted OR 0.90, 95% CI 0.78–1.05). Similar findings were reported in observational studies. Mathematical models indicated an important decrease in mortality when the population mask coverage is near-universal, regardless of mask efficacy. In the best-case scenario, when the mask efficacy is at 95%, the R0 can fall to 0.99 from an initial value of 16.90. Levels of mask filtration efficiency were heterogeneous, depending on the materials used (surgical mask: 45–97%). One laboratory study suggested a viral load reduction of 0.25 (95% CI 0.09–0.67) in favor of mask vs. no mask. / Interpretation: The findings of this systematic review and meta-analysis support the use of face masks in a community setting. Robust randomized trials on face mask effectiveness are needed to inform evidence-based policies. / PROSPERO registration: CRD42020184963

On the cosmological mass function theory

This paper provides, from one side, a review of the theory of the cosmological mass function from a theoretical point of view, starting from the seminal paper of Press & Shechter (1974) to the last developments (Del Popolo & Gambera (1998, 1999), Sheth & Tormen 1999 (ST), Sheth, Mo & Tormen 2001 (ST1), Jenkins et al. 2001 (J01), Shet & Tormen 2002 (ST2), Del Popolo 2002a, Yagi et al. 2004 (YNY)), and from another side some improvements on the multiplicity function models in literature. ...Comment: Astronomy Reports, in prin

On the Origin of the Inner Structure of Halos

We calculate by means of the Press-Schechter formalism the density profile developed by dark-matter halos during accretion, i.e., the continuous aggregation of small clumps. We find that the shape of the predicted profile is similar to that shown by halos in high-resolution cosmological simulations. Furthermore, the mass-concentration relation is correctly reproduced at any redshift in all the hierarchical cosmologies analyzed, except for very large halo masses. The role of major mergers, which can cause the rearrangement of the halo structure through violent relaxation, is also investigated. We show that, as a result of the boundary conditions imposed by the matter continuously infalling into the halo during the violent relaxation process, the shape of the density profile emerging from major mergers is essentially identical to the shape the halo would have developed through pure accretion. This result explains why, according to high-resolution cosmological simulations, relaxed halos of a given mass have the same density profile regardless of whether they have had a recent merger or not, and why both spherical infall and hierarchical assembly lead to very similar density profiles. Finally, we demonstrate that the density profile of relaxed halos is not affected either by the capture of clumps of intermediate mass.Comment: 14 pages, 8 figures, accepted for publication in ApJ. Minor changes, matches the published version. To appear in the ApJ August 10, 2003 issu