84 research outputs found

    Diamanti e sviluppo: Un’analisi critica degli stereotipi sui minatori della Sierra Leone

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    In the last decade, the Sierra Leone’s diamond mines have been the focus of an intense debate among analysts and experts of the development. Two main interrelated issues have been at stake in this debate: first, to understand the economic and political reasons that had supported the civil war from 1991 to 2002 and, second, to understand how to convert a potential “conflict commodity” in a resource for peace and prosperity. In this paper, I intend to highlight some recurring stereotypes of this debate. In particular, I will focus on a constellation of representations that depict the artisanal miners either as workers poorly organized and prone to irrational economic behavior, or as workers subjected to forms of exploitation akin to slavery. Based on fieldwork conducted in the diamond mining areas of Sierra Leone (2007-2011), this article intends to analyze the main forms of working organization and distribution of earnings among the miners. By challenging some stereotypes characterizing the development discourse, my aim is to show the cultural complexity and the historical density of the practices through which the miners face the risks and uncertainties of their job.In the last decade, the Sierra Leone’s diamond mines have been the focus of an intense debate among analysts and experts of the development. Two main interrelated issues have been at stake in this debate: first, to understand the economic and political reasons that had supported the civil war from 1991 to 2002 and, second, to understand how to convert a potential “conflict commodity” in a resource for peace and prosperity. In this paper, I intend to highlight some recurring stereotypes of this debate. In particular, I will focus on a constellation of representations that depict the artisanal miners either as workers poorly organized and prone to irrational economic behavior, or as workers subjected to forms of exploitation akin to slavery. Based on fieldwork conducted in the diamond mining areas of Sierra Leone (2007-2011), this article intends to analyze the main forms of working organization and distribution of earnings among the miners. By challenging some stereotypes characterizing the development discourse, my aim is to show the cultural complexity and the historical density of the practices through which the miners face the risks and uncertainties of their job

    Il medium irriducibile: Viaggio nella complessitĂ  del fumetto

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    Reseña de: BINDI, V. E RAFFAELLI, L., Che cos'Ú un fumetto, Roma, Carocci editore, 2021

    The Complex Story Behind a Deep Eutectic Solvent Formation as Revealed by L‑Menthol Mixtures with Butylated Hydroxytoluene Derivatives.

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    An in-depth study of the hydrophobic eutectic mixtures formed by L-menthol (MEN) with the butylated hydroxytoluene (BHT), 2-tert-butyl-pcresol (TBC), and p-cresol (PC) compounds has been carried out, where TBC and PC are analogous to the BHT species but with a different degree of steric hindrance around the hydroxyl group. Thermal characterization evidenced that the BHT/MEN system can be classified as an ideal eutectic, while the TBC/MEN and PC/MEN mixtures behave as type V deep eutectic solvents (DESs) for a wide range of compositions around the eutectic point. As shown by an array of experimental and theoretical methods, in the BHT/MEN mixtures the establishment of hydrogen-bond (H-bond) interactions between the components is dramatically hampered because of the steric hindrance in the BHT molecule, so that the achievement of a liquid phase at room temperature for the eutectic composition is driven by apolar−apolar attractions among the alkyl functional groups of the constituents. Differently, the TBC-MEN donor−receptor H-bond is the main driving force for the formation of a type V DES and derives from a concurrence of electronic and steric factors characterizing the TBC molecule. Finally, the absence of steric hindrance around the hydroxyl group allows the self-association among PC molecules through H-bonded networks already in the pristine compound, but the replacement with the more favorable PC-MEN H-bond provides a type V DES upon mixing of these components. Our combined approach, together with the peculiarity of the inspected systems, delivered an archetypal study able to shed light onto the various contributions ruling the structure− properties relationship in DESs and possibly deepening the currently accepted view of these inherently complex media

    Topological susceptibility in high temperature QCD: a new investigation with spectral projectors

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    We compute the topological susceptibility of high temperature QCD with 2+1 physical mass quarks using the multicanonical approach and the spectral projector estimate of the topological charge. This approach presents reduced lattice artifacts with respect to the standard gluonic one, and makes it possible to perform a reliable continuum extrapolation

    A Real-World, Multicenter, Observational Retrospective Study of Durvalumab After Concomitant or Sequential Chemoradiation for Unresectable Stage III Non-Small Cell Lung Cancer

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    Introduction: For unresectable stage III non-small cell lung cancer (NSCLC), the standard therapy consists of chemoradiotherapy (CRT) followed by durvalumab maintenance for responding patients. The present study reports on the safety and outcome of durvalumab use after CRT in a real-world, multicenter, retrospective cohort. Methods: Two hundred thirty-eight patients have been included. We collected data on systemic therapy, radiation therapy, the timing between CRT and durvalumab, number of durvalumab cycles, reasons for non-starting or discontinuation, incidence and grade of adverse events (AEs), and progression-free survival (PFS) and overall survival (OS). Results: One hundred fifty-five patients out of 238 (65.1%) received at least one durvalumab dose: 91 (58.7%) after concomitant CRT (cCRT) and 64 (41.3%) after sequential CRT (sCRT). Programmed-death ligand 1 (PD-L1) status was unknown in 7/155 (4.5%), negative in 14 (9.1%), and positive ≄1% in 134/155 (86.4%). The main reasons for non-starting durvalumab were progression (10.1%), PD-L1 negativity (7.5%), and lung toxicity (4.6%). Median follow-up time was 14 months (range 2–29); 1-year PFS and OS were 83.5% (95%CI: 77.6–89.7) and 97.2% (95%CI: 94.6–99.9), respectively. No significant differences in PFS or OS were detected for cCRT vs. sCRT, but the median PFS was 13.5 months for sCRT vs. 23 months for cCRT. Potentially immune-related AEs were recorded in 76/155 patients (49.0%). Pneumonitis was the most frequent, leading to discontinuation in 11/155 patients (7.1%). Conclusions: Durvalumab maintenenace after concurrent or sequential chemoradiation for unresectable, stage III NSCLC showed very promising short-term survival results in a large, multicenter, restrospective, real-world study. Durvalumab was the first drug obtaining a survival benefit over CRT within the past two decades, and the present study contributes to validating its use in clinical practice

    Raman investigation of laser-induced structural defects of graphite oxide films

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    Since the beginning of intensive studies on graphene and graphitic materials, Raman spectroscopy has always been used as a characterisation technique. This is due to two main reasons: the non-destructive nature of this experimental technique and its ability to distinguish between the plethora of existing carbon materials. One of the most challenging research activities concerns the production of graphene microcircuits. To address this issue, a possible strategy is to directly reduce and pattern graphite oxide (GO) film by laser irradiation. The objective of this study is to evaluate the laser irradiation-induced structural changes on thin GO films by using Micro-Raman spectroscopy. We used as a source a Nd:YAG laser (1064 nm) and different laser fluences: 15 J/cm2, 7.5 J/cm2 and 5 J/cm2. We have analyzed the modifications of the main Raman contributions of these graphitic materials: the D band (defect induced band), the G band (band due to sp2 hybridized carbon atoms) and the 2D band (D band overtone). In particular, we found out that our figure of merit (FOM) parameters, i.e. the intensity ratio ID/IG (for the D band and G band) and I2D/IG (for the 2D band and G band), change with the laser fluences, revealing a different effect induced by the laser irradiation. The best results are found in the sample irradiated with 5 J/cm2, suggesting that higher fluences do not lead to better results

    Differential diagnosis of neurodegenerative dementias with the explainable MRI based machine learning algorithm MUQUBIA

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    Biomarker-based differential diagnosis of the most common forms of dementia is becoming increasingly important. Machine learning (ML) may be able to address this challenge. The aim of this study was to develop and interpret a ML algorithm capable of differentiating Alzheimer's dementia, frontotemporal dementia, dementia with Lewy bodies and cognitively normal control subjects based on sociodemographic, clinical, and magnetic resonance imaging (MRI) variables. 506 subjects from 5 databases were included. MRI images were processed with FreeSurfer, LPA, and TRACULA to obtain brain volumes and thicknesses, white matter lesions and diffusion metrics. MRI metrics were used in conjunction with clinical and demographic data to perform differential diagnosis based on a Support Vector Machine model called MUQUBIA (Multimodal Quantification of Brain whIte matter biomArkers). Age, gender, Clinical Dementia Rating (CDR) Dementia Staging Instrument, and 19 imaging features formed the best set of discriminative features. The predictive model performed with an overall Area Under the Curve of 98%, high overall precision (88%), recall (88%), and F1 scores (88%) in the test group, and good Label Ranking Average Precision score (0.95) in a subset of neuropathologically assessed patients. The results of MUQUBIA were explained by the SHapley Additive exPlanations (SHAP) method. The MUQUBIA algorithm successfully classified various dementias with good performance using cost-effective clinical and MRI information, and with independent validation, has the potential to assist physicians in their clinical diagnosis

    Transforming matters: sustaining gold lifeways in artisanal and small-scale mining

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    Growth strategies in mining regions promote gold extraction basedonindustrial mining, associating Artisanal and Small-scale Gold Mining (ASGM) with persistent informality. Against this background, we consider how to approach transformations to sustainability in ASGM. Acknowledging how problematic this topic is for sustainability debates,given howASGM is associated with a host of environmental and social problems,we argue that a justice lens demands we confront such challenges within the global politics of sustainability. This leads us to review advances inthe study of ASGM, linked to debates on extractivism, resource materialities, and informality. We use the notion of gold lifeways to capture how the matter of mining shapes different worlds of extraction. We argue that consideration of the potential for transformations to sustainability needs to be grounded within the realities of ASGM. This necessitates giving value to miners’ knowledge(s), perspectives and interests, while recognising the plurality of mining futures. Nevertheless, we conclude that between the immediacy of precarious work and the structural barriers to change in ASGM, the challenges for transformation cannot be underestimated.NWOGlobal Challenges (FSW

    Geographical heterogeneity of clinical and serological phenotypes of systemic sclerosis observed at tertiary referral centres. The experience of the Italian SIR-SPRING registry and review of the world literature

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    Introduction: Systemic sclerosis (SSc) is characterized by a complex etiopathogenesis encompassing both host genetic and environmental -infectious/toxic- factors responsible for altered fibrogenesis and diffuse microangiopathy. A wide spectrum of clinical phenotypes may be observed in patients' populations from different geographical areas. We investigated the prevalence of specific clinical and serological phenotypes in patients with definite SSc enrolled at tertiary referral centres in different Italian geographical macro-areas. The observed findings were compared with those reported in the world literature.Materials and methods: The clinical features of 1538 patients (161 M, 10.5%; mean age 59.8 +/- 26.9 yrs.; mean disease duration 8.9 +/- 7.7 yrs) with definite SSc recruited in 38 tertiary referral centres of the SPRING (Systemic sclerosis Progression INvestiGation Group) registry promoted by Italian Society of Rheumatology (SIR) were obtained and clustered according to Italian geographical macroareas.Results: Patients living in Southern Italy were characterized by more severe clinical and/or serological SSc phenotypes compared to those in Northern and Central Italy; namely, they show increased percentages of diffuse cutaneous SSc, digital ulcers, sicca syndrome, muscle involvement, arthritis, cardiopulmonary symptoms, interstitial lung involvement at HRCT, as well increased prevalence of serum anti-Scl70 autoantibodies. In the same SSc population immunusppressive drugs were frequently employed. The review of the literature underlined the geographical heterogeneity of SSc phenotypes, even if the observed findings are scarcely comparable due to the variability of methodological approaches.Conclusion: The phenotypical differences among SSc patients' subgroups from Italian macro-areas might be correlated to genetic/environmental co-factors, and possibly to a not equally distributed national network of information and healthcare facilities
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