34,474 research outputs found
Deflation by Expenditure Components: A Harmless Adjustment?
No full textWe investigate the effect that seemingly minor features of the implementation of cost-of-living adjustments have on the distribution of household expenditures, by developing an analytical framework that is consistent with standard consumer theory, and mindful of data limitations faced by practitioners. The main result is at odds with common sense: even when multiple price indices are available (e.g., a food Consumer Price Index and a non-food one), it turns out that using a single price index (e.g., the total Consumer Price Index), to adjust the consumption aggregate is recommended. The practice of adjusting subcomponents of consumption separately (food with a food index and nonfood with a nonfood index) can lead to a systematic bias in the welfare measure, and consequently in poverty and inequality measures. Using Iran's 2019 Household Expenditures and Income Survey, we find that the bias manifests as a systematic underestimation of urban poverty and overestimation of rural poverty
First ALMA Maps of Cosmic-Ray Ionization Rate in High-mass Star-forming Regions
No full textLow-energy cosmic rays (<1 TeV) are a pivotal source of ionization of the interstellar medium, where they play a central role in determining the gas chemical composition and drastically influence the formation of stars and planets. Over the past few decades, H3 + absorption line observations in diffuse clouds have provided reliable estimates of the cosmic-ray ionization rate relative to H2 ( ζionH2
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estimates are, therefore, still provisional in this context and represent one of the least understood components when it comes to defining general models of star and planet formation. In this Letter, we present the first high-resolution maps of the ζionH2
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in two high-mass clumps obtained with a new analytical approach recently proposed to estimate the ζionH2
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in the densest regions of molecular clouds. We obtain ⟨ζionH2⟩
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that span from 3 × 10-17 to 10-16 s-1, depending on the different distribution of the main ion carriers, in excellent agreement with the most recent cosmic-ray propagation models. The cores belonging to the same parental clump show comparable ζionH2
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, suggesting that the ionization properties of prestellar regions are determined by global rather than local effects. These results provide important information for the chemical and physical modeling of star-forming regions
Systematic review: Features, diagnosis, management and prognosis of hepatic hematoma, a rare complication of ERCP
No full textBackground: Hepatic hematoma (HH) is a rare but severe adverse event following endoscopic retrograde cholangiopancreatography (ERCP). Aims: To perform a systematic literature review and describe two additional cases, one of which presenting multiple subcapsular/intrahepatic hematomas after ERCP. Methods: The literature review was performed in PubMed/MEDLINE, EMBASE, and SCOPUS to identify all cases reporting on HH after ERCP. Results: A total of 48 cases (females 63%, mean age 58.2 ± 20.6 years) were included. The mean symptoms onset time was 46.8 h after ERCP, and the most common symptoms were abdominal pain (91.7%), anaemia (43.8%), hypotension (29.2%) and fever (20.8%). All cases were diagnosed by computed tomography (CT). HH was found mostly in the right hepatic lobe (95.1%) and the mean size was 116 × 93 mm. A conservative management was adopted in 38.3% of cases, while percutaneous drainage, embolization and surgery were needed in 31.9%, 14.9% and 25%. Mortality rate was about 9%. Anaemia (OR 6.9; p = 0.02) and surgery (OR 10.5; p < 0.01) were the only independent factors for unfavorable outcome (death), while abdominal pain (OR 0.1; p = 0.03) and antibiotics administration (OR 0.06; p < 0.001) were associated with better outcome. Conclusions: HH is a rare but severe complication following ERCP which needs a multidisciplinary approach. Antibiotics administration is the only treatment able to reduce the risk of death
Beyond Cultural Aphasia.
No full textA Conversation between Rossella Ciocca and the scholar and cultural activist G. N. Devy, author of the People's Linguistic Survey of India, about nomadic communities and their endangered languages and cultures
Bioartificial polymer membranes as innovative systems for biomedical or biotechnological uses
No full textLinee Guida per la riabilitazione dei bambini affetti da spina bifida
No full textLa Società Italiana di Medicina Fisica e Riabilitazione (SIMFER), in relazione ai propri compiti statutari e sulla base di indicazioni del Dipartimento di Programmazione del Ministero della Sanità, ha dato incarico ad una commissione di Soci di elaborare ""Linee guida per la riabilitazione dei bambini affetti da spina bifida
Hierarchical nanomechanics of collagen microfibrils
No full textCollagen constitutes one third of the human proteome, providing mechanical stability, elasticity and strength to connective tissues. Collagen is also the dominating material in the extracellular matrix (ECM) and is thus crucial for cell differentiation, growth and pathology. However, fundamental questions remain with respect to the origin of the unique mechanical properties of collagenous tissues, and in particular its stiffness, extensibility and nonlinear mechanical response. By using x-ray diffraction data of a collagen fibril reported by Orgel et al. (Proceedings of the National Academy of Sciences USA, 2006) in combination with protein structure identification methods, here we present an experimentally validated model of the nanomechanics of a collagen microfibril that incorporates the full biochemical details of the amino acid sequence of the constituting molecules. We report the analysis of its mechanical properties under different levels of stress and solvent conditions, using a full-atomistic force field including explicit water solvent. Mechanical testing of hydrated collagen microfibrils yields a Young’s modulus of ≈300 MPa at small and ≈1.2 GPa at larger deformation in excess of 10% strain, in excellent agreement with experimental data. Dehydrated, dry collagen microfibrils show a significantly increased Young’s modulus of ≈1.8 to 2.25 GPa (or ≈6.75 times the modulus in the wet state) owing to a much tighter molecular packing, in good agreement with experimental measurements (where an increase of the modulus by ≈9 times was found). Our model demonstrates that the unique mechanical properties of collagen microfibrils can be explained based on their hierarchical structure, where deformation is mediated through mechanisms that operate at different hierarchical levels. Key mechanisms involve straightening of initially disordered and helically twisted molecules at small strains, followed by axial stretching of molecules, and eventual molecular uncoiling at extreme deformation. These mechanisms explain the striking difference of the modulus of collagen fibrils compared with single molecules, which is found in the range of 4.8±2 GPa or ≈10-20 times greater. These findings corroborate the notion that collagen tissue properties are highly scale dependent and nonlinear elastic, an issue that must be considered in the development of models that describe the interaction of cells with collagen in the extracellular matrix. A key impact the atomistic model of collagen microfibril mechanics reported here is that it enables the bottom-up elucidation of structure-property relationships in the broader class of collagen materials such as tendon or bone, including studies in the context of genetic disease where the incorporation of biochemical, genetic details in material models of connective tissue is essential
Comparazione di metodi termovisivi per l’identificazione di aree umide su materiali dell’edilizia storica
No full textWater content inside building materials (plaster, brick, stone) is usefull to evaluate their decay level. Passive and active termography are compared, in order to define the most reliable procedure, firstly to map the moisture diffusion and secondary to evaluate the moisture content in the surfaces. Laboratory researches carried out in the last decades and scientific literature permitted to determine that the superficial decay in porous materials is more related to the evaporative speed of the surfaces and the presence of soluble salts than to their absorption capability. Moreover, evaporative fluxes were studied at different environmental conditions and water content in order to find out a correlation between moisture content, evaporation and boundary conditions. The thermal characteristics of timber are highly different from the characteristics of porous materials such as brick and stone and mortar, particularly the thermal capacity of wood is lower. Nevertheless, because of the lower heat capacity of wood, the presence of water greatly affects the wood thermal capacity: the active procedure, guarantees the best results. Lab tests and study case permit to evaluate the sensitivity of the method
Gender-gap in randomized clinical trials reporting mortality in the perioperative setting and critical care: 20 years behind the scenes
No full textBackground: Women researchers might experience obstacles in academic environments and might be underrepresented in the authorship of articles published in peer-reviewed journals. Material and Methods: This is a cross-sectional analysis of female-led RCTs describing all interventions reducing mortality in critically ill and perioperative patients from 1981 to December 31, 2020. We searched PubMed/MEDLINE and EMBASE with the keywords RCTs and mortality. The gender of the first author was extracted and descriptive analysis was performed including the year of publication, impact factor, country of the first author, and methodological aspects. Results: We analyzed 340 RCTs, of which 42 (12%) were led by female researchers. The presence of women increased from 8% (14/172) until 2010 up to 17% (28/168) in 2010 and beyond. The United States, the United Kingdom, and Brazil were the main countries of origin of female researchers. Women authors conducted mainly single-center and single-nation studies as compared to male authors. The median impact factor of the target journal was 6 (3-27) in women vs. 7 (3-28) in men, with a p-value of 0.67; Critical Care Medicine, JAMA, and The New England Journal of Medicine were the most frequent target journals for both women and men. Conclusion: In the last 40 years, only one out of eight RCTs had a woman as the first author but the presence of women increased up to 17% by 2010 and beyond. The impact factor of publication target journals was high and not different between genders
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