78 research outputs found
«Geografia e ambiente» in Italia: una lettura critica condivisa
Questo articolo introduttivo ripercorre le fasi che hanno portato alla realizzazione del numero monografico Geografia e ambiente dell’omonimo gruppo A.Ge.I. Dopo un breve inquadramento i curatori presentano il lavoro emerso sia da incontri tematici preliminari, sia dai saggi degli autori che, singolarmente o in gruppo, hanno utilizzato punti di vista, metodologie, presupposti di indagine, temi, aree e scale di analisi diverse tra loro, senza perdere di vista il fuoco di questo numero tematico. Il suo obiettivo ultimo è quello di comprendere in maniera critica le profonde relazioni che in Italia sussistono tra i territori e le popolazioni che li vivono e ne utilizzano le risorse, il degrado che talvolta ne scaturisce, ma anche le sfide che emergono e le opportunità che vengono offerte dalla riqualificazione di tali territori.This introductory article retraces the steps that led to the realization of the monographic issue of the homonymous group A.Ge.I. Geografia e Ambiente. After a brief overview, the editors present the work that emerged from both preliminary thematic meetings, and from the essays of the authors who, individually or in groups, have used different points of view, methodologies, assumptions of investigation, themes, areas and scales of analysis, without losing sight of the focus of this thematic issue. Its ultimate goal is to understand in a critical way the deep relationships that exist in Italy between the territories and the people who live there and use their resources, the degradation that sometimes results, but also the challenges that emerge and the opportunities that are offered by the redevelopment of these territories
Cationic Polystyrene-Based Hydrogels as Efficient Adsorbents to Remove Methyl Orange and Fluorescein Dye Pollutants from Industrial Wastewater
Water pollution from dyes is harmful to the environment, plants, animals, and humans
and is one of the most widespread problems afflicting people throughout the world. Adsorption
is a widely used method to remove contaminants derived from the textile industry, food colorants,
printing, and cosmetic manufacturing from water. Here, aiming to develop new low-cost and up scalable adsorbent materials for anionic dye remediation and water decontamination by electrostatic
interactions, two cationic resins (R1 and R2) were prepared. In particular, they were obtained by
copolymerizing 4-ammonium methyl and ethyl styrene monomers (M1 and M2) with dimethy lacrylamide (DMAA), using N-(2-acryloylamino-ethyl)-acrylamide (AAEA) as cross-linker. Once
characterized by several analytical techniques, upon their dispersion in an excess of water, R1 and R2
provided the R1- and R2-based hydrogels (namely R1HG and R2HG) with equilibrium degrees of
swelling (EDS) of 900% and 1000% and equilibrium water contents (EWC) of 90 and 91%, respectively.
By applying Cross’ rheology equation to the data of R1HG and R2HG’s viscosity vs. shear rate, it was
established that both hydrogels are shear thinning fluids with pseudoplastic/Bingham plastic behav ior depending on share rate. The equivalents of -NH3
+ groups, essential for the electrostatic-based
absorbent activity, were estimated by the method of Gaur and Gupta on R1 and R2 and by potentio metric titrations on R1HG and R2HG. In absorption experiments in bulk, R1HG and R2HG showed
high removal efficiency (97–100%) towards methyl orange (MO) azo dye, fluorescein (F), and their
mixture (MOF). Using F or MO solutions (pH = 7.5, room temperature), the maximum absorption was
47.8 mg/g in 900
(F) and 47.7 mg/g in 1200
(MO) for R1, while that of R2 was 49.0 mg/g in 200
(F) and
48.5 mg/g in 300
(MO). Additionally, R1HG and R2HG-based columns, mimicking decontamination
systems by filtration, were capable of removing MO, F, and MOF from water with a 100% removal
efficiency, in different conditions of use. R1HG and R2HG represent low-cost and up-scalable column
packing materials that are promising for application in industrial wastewater treatment
FLASH radiotherapy with electrons: issues related to the production, monitoring, and dosimetric characterization of the beam
Various in vivo experimental works carried out on different animals and organs have shown that it is possible to reduce the damage caused to healthy tissue still preserving the therapeutic efficacy on the tumor tissue, by drastically reducing the total time of dose delivery (<200 ms). This effect, called the FLASH effect, immediately attracted considerable attention within the radiotherapy community, due to the possibility of widening the therapeutic window and treating effectively tumors which appear radioresistant to conventional techniques. Despite the experimental evidence, the radiobiological mechanisms underlying the FLASH effect and the beam parameters contributing to its optimization are not yet known in details. In order to fully understand the FLASH effect, it might be worthy to investigate some alternatives which can further improve the tools adopted so far, in terms of both linac technology and dosimetric systems. This work investigates the problems and solutions concerning the realization of an electron accelerator dedicated to FLASH therapy and optimized for in vivo experiments. Moreover, the work discusses the saturation problems of the most common radiotherapy dosimeters when used in the very high dose-per-pulse FLASH conditions and provides some preliminary experimental data on their behavior
Applying multidimensional computerized adaptive testing to the MSQOL-54: a simulation study
Background: The Multiple Sclerosis Quality of Life-54 (MSQOL-54) is one of the most commonly-used MS-specific health-related quality of life (HRQOL) measures. It is a multidimensional, MS-specific HRQOL inventory, which includes the generic SF-36 core items, supplemented with 18 MS-targeted items. Availability of an adaptive short version providing immediate item scoring may improve instrument usability and validity. However, multidimensional computerized adaptive testing (MCAT) has not been previously applied to MSQOL-54 items. We thus aimed to apply MCAT to the MSQOL-54 and assess its performance. Methods: Responses from a large international sample of 3669 MS patients were assessed. We calibrated 52 (of the 54) items using bifactor graded response model (10 group factors and one general HRQOL factor). Then, eight simulations were run with different termination criteria: standard errors (SE) for the general factor and group factors set to different values, and change in factor estimates from one item to the next set at < 0.01 for both the general and the group factors. Performance of the MCAT was assessed by the number of administered items, root mean square difference (RMSD), and correlation. Results: Eight items were removed due to local dependency. The simulation with SE set to 0.32 (general factor), and no SE thresholds (group factors) provided satisfactory performance: the median number of administered items was 24, RMSD was 0.32, and correlation was 0.94. Conclusions: Compared to the full-length MSQOL-54, the simulated MCAT required fewer items without losing precision for the general HRQOL factor. Further work is needed to add/integrate/revise MSQOL-54 items in order to make the calibration and MCAT performance efficient also on group factors, so that the MCAT version may be used in clinical practice and research
Reciprocal Regulation Between Smad7 and Sirt1 in the Gut
In inflammatory bowel disease (IBD) mucosa, there is over-expression of Smad7, an intracellular inhibitor of the suppressive cytokine transforming growth factor-β1, due to post-transcriptional mechanisms that enhance Smad7 acetylation status thus preventing ubiquitination-mediated proteosomal degradation of the protein. IBD-related inflammation is also marked by defective expression of Sirt1, a class III NAD+-dependent deacetylase, which promotes ubiquitination-mediated proteosomal degradation of various intracellular proteins and triggers anti-inflammatory signals. The aim of our study was to determine whether, in IBD, there is a reciprocal regulation between Smad7 and Sirt1. Smad7 and Sirt1 were examined in mucosal samples of IBD patients and normal controls by Western blotting and immunohistochemistry, and Sirt1 activity was assessed by a fluorimetric assay. To determine whether Smad7 is regulated by Sirt1, normal or IBD lamina propria mononuclear cells (LPMC) were cultured with either Sirt1 inhibitor (Ex527) or activator (Cay10591), respectively. To determine whether Smad7 controls Sirt1 expression, ex vivo organ cultures of IBD mucosal explants were treated with Smad7 sense or antisense oligonucleotide. Moreover, Sirt1 expression was evaluated in LPMC isolated from Smad7-transgenic mice given dextran sulfate sodium (DSS). Upregulation of Smad7 was seen in both the epithelial and lamina propria compartments of IBD patients and this associated with reduced expression and activity of Sirt1. Activation of Sirt1 in IBD LPMC with Cay10591 reduced acetylation and enhanced ubiquitination-driven proteasomal-mediated degradation of Smad7, while inhibition of Sirt1 activation in normal LPMC with Ex527 increased Smad7 expression. Knockdown of Smad7 in IBD mucosal explants enhanced Sirt1 expression, thus suggesting a negative effect of Smad7 on Sirt1 induction. Consistently, mucosal T cells of Smad7-transgenic mice contained reduced levels of Sirt1, a defect that was amplified by induction of DSS colitis. The data suggest the existence of a reciprocal regulatory mechanism between Smad7 and Sirt1, which could contribute to amplify inflammatory signals in the gut
Viability of a MSQOL-54 general health-related quality of life score using bifactor model
Background MSQOL-54 is a multidimensional, widely-used, health-related quality of life (HRQOL) instrument specific for multiple sclerosis (MS). Findings from the validation study suggested that the two MSQOL-54 composite scores are correlated. Given this correlation, it could be assumed that a unique total score of HRQOL may be calculated, with the advantage to provide key stakeholders with a single overall HRQOL score. We aimed to assess how well the bifactor model could account for the MSQOL-54 structure, in order to verify whether a total HRQOL score can be calculated. Methods A large international database (3669 MS patients) was used. By means of confirmatory factor analysis, we estimated a bifactor model in which every item loads onto both a general factor and a group factor. Fit of the bifactor model was compared to that of single and two second-order factor models by means of Akaike information and Bayesian information criteria reduction. Reliability of the total and subscale scores was evaluated with Mc Donald's coefficients (omega, and omega hierarchical). Results The bifactor model outperformed the two second-order factor models in all the statistics. All items loaded satisfactorily (>= 0.40) on the general HRQOL factor, except the sexual function items. Omega coefficients for total score were very satisfactory (0.98 and 0.87). Omega hierarchical for subscales ranged between 0.22 to 0.57, except for the sexual function (0.70). Conclusions The bifactor model is particularly useful when it is intended to acknowledge multidimensionality and at the same time take account of a single general construct, as the HRQOL related to MS. The total raw score can be used as an estimate of the general HRQOL latent score
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