1,699 research outputs found
Do prosocial-certified companies walk the talk? An analysis of B Corps' contributions to Sustainable Development Goals
This paper investigates the contribution of the B Corp movement in Europe to achieving Sustainable Development Goals (SDGs) compared with non-B Corps. B Corp certification aims to identify organisations that utilise business as 'a force for good', but there is limited empirical evidence on how effectively certified organisations translate their prosocial claims into measurable SDG contributions. We address this through cluster analysis, comparing 313 B Corp-certified and 1506 non-certified European companies by way of the SDG Action Manager tool. Our findings reveal three clusters of B Corp-certified organisations with varying contribution levels across all SDGs, indicating that the certification does not consistently identify organisations with significant SDG impacts. Non-certified companies, meanwhile, do not exhibit distinct patterns. These results raise doubts about whether the B Corp category identifies a distinctive prototype member that can define clear prosocial norms and practices. The paper contributes to understanding B Corp organisations' narratives by providing insights into their empirical performance compared with non-certified organisations. It also offers potential explanations for these discrepancies and proposes strategies to strengthen B Corp certification bodies in alignment with the SDGs, while acknowledging the presence of intra-category variations
Hfq affects mRNA levels independently of degradation
<p>Abstract</p> <p>Background</p> <p>The bacterial Lsm protein, Hfq, is an RNA chaperone involved in many reactions related to RNA metabolism, such as replication and stability, control of small RNA activity and polyadenylation. Despite this wide spectrum of known functions, the global role of Hfq is almost certainly undervalued; its capacity to bind DNA and to interact with many other proteins are only now beginning to be taken into account.</p> <p>Results</p> <p>The role of Hfq in the maturation and degradation of the <it>rpsO </it>mRNA of <it>E. coli </it>was investigated <it>in vivo</it>. The data revealed a decrease in <it>rpsO </it>mRNA abundance concomitant to an increase in its stability when Hfq is absent. This indicates that the change in mRNA levels in <it>hfq </it>mutants does not result from its modification of RNA stability. Moreover, a series of independent experiments have revealed that the decrease in mRNA level is not a consequence of a reduction of translation efficiency and that Hfq is not directly implicated in translational control of <it>rpsO </it>expression. Reduced steady-state mRNA levels in the absence of Hfq were also shown for <it>rpsT, rpsB </it>and <it>rpsB-tsf</it>, but not for <it>lpp, pnp </it>or tRNA transcripts. The abundance of chimeric transcripts <it>rpsO-lacZ </it>and <it>rpsB-lacZ</it>, whose expression was driven by <it>rpsO </it>and <it>rpsB </it>promoters, respectively, was also lower in the <it>hfq </it>null-mutants, while the β-galactosidase yield remained about the same as in the parent wild-type strain.</p> <p>Conclusions</p> <p>The data obtained suggest that alteration of <it>rpsO, rpsT </it>and <it>rpsB-tsf </it>transcript levels observed under conditions of Hfq deficiency is not caused by the post-transcriptional events, such as mRNA destabilization or changes in translation control, and may rather result from changes in transcriptional activity. So far, how Hfq affects transcription remains unclear. We propose that one of the likely mechanisms of Hfq-mediated modulation of transcription might operate early in the elongation step, when interaction of Hfq with a nascent transcript would help to overcome transcription pauses and to prevent preliminary transcript release.</p
The role of the capping agent and nanocrystal size in photoinduced hydrogen evolution using CdTe/CdS quantum dot sensitizers
Hydrogen production via light-driven water splitting is a key process in the context of solar energy conversion. In this respect, the choice of suitable light-harvesting units appears as a major challenge, particularly as far as stability issues are concerned. In this work, we report on the use of CdTe/CdS QDs as photosensitizers for light-assisted hydrogen evolution in combination with a nickel bis(diphosphine) catalyst (1) and ascorbate as the sacrificial electron donor. QDs of different sizes (1.7-3.4 nm) and with different capping agents (MPA, MAA, and MSA) have been prepared and their performance assessed in the above-mentioned photocatalytic reaction. Detailed photophysical studies have been also accomplished to highlight the charge transfer processes relevant to the photocatalytic reaction. Hydrogen evolution is observed with remarkable efficiencies when compared to common coordination compounds like Ru(bpy)32+ (where bpy = 2,2′-bipyridine) as light-harvesting units. Furthermore, the hydrogen evolution performance under irradiation is strongly determined by the nature of the capping agent and the QD size and can be related to the concentration of the surface defects within the semiconducting nanocrystal. Overall, the present results outline how QDs featuring large quantum yields and long lifetimes are desirable to achieve sustained hydrogen evolution upon irradiation and that a precise control of the structural and photophysical properties thus appears as a major requirement towards profitable photocatalytic applications
On the existence of supergravity duals to D1--D5 CFT states
We define a metric operator in the 1/2-BPS sector of the D1-D5 CFT, the
eigenstates of which have a good semi-classical supergravity dual; the
non-eigenstates cannot be mapped to semi-classical gravity duals. We also
analyse how the data defining a CFT state manifests itself in the gravity side,
and show that it is arranged into a set of multipoles. Interestingly, we find
that quantum mechanical interference in the CFT can have observable
manifestations in the semi-classical gravity dual. We also point out that the
multipoles associated to the normal statistical ensemble fluctuate wildly,
indicating that the mixed thermal state should not be associated to a
semi-classical geometry.Comment: 22 pages, 2 figures. v2 : references added, typos correcte
About the strength of correlation effects in the electronic structure of iron
The strength of electronic correlation effects in the spin-dependent
electronic structure of ferromagnetic bcc Fe(110) has been investigated by
means of spin and angle-resolved photoemission spectroscopy. The experimental
results are compared to theoretical calculations within the three-body
scattering approximation and within the dynamical mean-field theory, together
with one-step model calculations of the photoemission process. This comparison
indicates that the present state of the art many-body calculations, although
improving the description of correlation effects in Fe, give too small mass
renormalizations and scattering rates thus demanding more refined many-body
theories including non-local fluctuations.Comment: 4 pages, 4 figure
Realization and high power tests of damped C-band accelerating structures for the ELI-NP linac
Covid-19 lockdown impacts among patients with cystic fibrosis. an italian regional reference centre experience
Background: Coronavirus pandemic has influenced our society with social distancing and management of chronic disease such as cystic fibrosis (CF). During the Italian lockdown from March to May 2020, CF patients reduced the number of outpatient visits, limited social interactions and spent more time at home. The aim of this study is to evaluate the impact of the lockdown on body mass index (BMI) and lung function tests on CF patients. Methods: We retrospectively reviewed clinical data about 111 CF patients followed in our Regional Cystic Fibrosis Reference Centre (Policlinico Umberto I, Rome) according to two periods: pre-lockdown (from October 2019-March 2020) and post-lockdown (from May 2020-October 2020). We collected data on nutritional (BMI and body weight) and lung function status; we chose the best values of the 'pre-lockdown' and 'post-lockdown' period for each patient. Patients were divided into 3 groups according to FEV1 value (Forced Expiratory Volume in the 1st second): group 1 (FEV1 <40%), group 2 (FEV1 40-70%), group 3 (FEV1 >70%). All patients received a telephone interview asking for the number of hours per week devoted to physical activity, number of pulmonary acute exacerbations and subjective evaluation of adherence to medical therapy, respiratory physiotherapy and diet, during the two periods. Results: Comparing weight, BMI and respiratory function between pre and post lockdown periods, we noticed an increase in weight during among overall patients. Male patients improved weight, BMI, FEF 25-75% (Forced Expiratory flow between 25% and 75% of vital capacity) and Tiffenau index more than female patients. The most severely compromised patients (group 1), showed a significant loss of both weight and BMI. Instead, patients with moderate respiratory function (group 2) showed a significant increase of both weight and BMI and a slightly reduced CVF (Forced Vital capacity). We found no differences among patients with good respiratory function (group 3). Comparing each clinical sub-groups, we noticed a significative improvement of weight (p = 0.018) and BMI (p = 0.030) among patients with moderate respiratory function compared to patients with compromised respiratory function. During lockdown, patients reported less physical activity, no variation in food amount and composition, more adherence to therapy (43%) and more consistent daily respiratory physiotherapy (47.6%). Conclusions: Lockdown period had benefit among CF patients in terms of weight in particular in male patient. The greatest benefit on nutritional state was observed in patients with moderate reduction of respiratory function. In addition, we noted a stabilization and sometimes a slight improvement of lung function, instead of a continuous and steady decline that is normally observed in CF patients. These beneficial effects are slight but significative, bearing in mind the general worsening that CF patients experience annually
Design, realization and test of C-band accelerating structures for the SPARC_LAB linac energy upgrade
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