616 research outputs found
Communicating Corporate Social Responsibility through Twitter: a topic model analysis on selected companies
[EN] Social media are fundamental in creating new opportunities for firms and they
represent a relevant tool for the communication and the engagement with
customers. The purpose of this paper is to analyse the communication of
Corporate Social Responsibility (CSR) activities on Twitter. We consider the
listed companies included in the Dow Jones Industrial Average Index and we
implement a topic model analysis on their timelines. In order to identify the
topic discussed, their correlation, and their evolution over time and sectors,
we apply the Structural Topic Model algorithm, which allows estimating the
model including document-level metadata. This model proves to be a powerful
tool for topic detection and for estimating the effects of document-level
metadata. Indeed, we find that the topics are overall well identified, and the
model allows catching signals from the data. Finally, we discuss issues related
to the validity of the analysis, including data quality problems.Salvatore, C.; Bianchi, A.; Biffignandi, S. (2020). Communicating Corporate Social Responsibility through Twitter: a topic model analysis on selected companies. Editorial Universitat Politècnica de València. 269-277. https://doi.org/10.4995/CARMA2020.2020.11646OCS26927
Collaborate for what: a structural topic model analysis on CDP data
[EN] The aim of this paper is to understand why firms engage with their suppliers to collaborate for sustainability. To this purpose, we use the Carbon Disclosure Project (CDP) Supply Chain dataset and apply the Structural Topic Model to 1) identify the topics discussed in an open-ended question related to climate-related supplier engagement and 2) estimate the differences in the discussion of such topics between CDP members and non-members, respectively focal firms and first-tier suppliers. The analysis highlights that the two most prevalent reasons firms engage with their suppliers relate to several aspects of the management of the supply chain, and the services and goods mobility efficiency. It is further noted how first-tier suppliers do not dispose of established capabilities and, therefore, are still in the course of improving their processes. On the contrary, focal firms have more structured capabilities so to manage supplier engagement for information collection. This study demonstrates how big data and machine learning methods can be applied to analyse unstructured textual data from traditional surveys.Salvatore, C.; Madonna, A.; Bianchi, A.; Boffelli, A.; Kalchschmidt, M. (2022). Collaborate for what: a structural topic model analysis on CDP data. En 4th International Conference on Advanced Research Methods and Analytics (CARMA 2022). Editorial Universitat Politècnica de València. 139-146. https://doi.org/10.4995/CARMA2022.2022.1507413914
Selective arterial embolization for a high-flow priapism following perineal trauma in a young gymnast
Introduction. High-flow priapism is a rare condition in children, usually due to a perineal trauma. Materials and methods. We present a case of traumatic highflow priapism investigated by Doppler ultrasound and managed by angiography and selective embolization of a branch of the internal pudendal artery. Results. A 13-year-old gymnast underwent perineal trauma during training and developed a high-flow priapism. The first ultrasound (immediately after the trauma) showed the presence of an inhomogeneous area of 3 x 2 cm associated with an anechoic vascularized area (pseudoaneurysm) in the right corpus cavernosum. On the left side there was a similar finding, but of smaller size. After 3 weeks the pseudoaneurysm on the left was completely obliterated while the right one was still present. Angiography and superselective catheterization of a branch of the left pudendal artery and its embolization with microspheres and with metal microcoils were performed. After the procedure, ultrasound showed that the right pseudoaneurysm was completely obliterated and there were no more branches reaching it. The cavernous arteries were both pervious. Conclusions. Selective arterial embolization is a safe treatment that can also be used in pediatric patients
A case report of thyroid carcinoma confined to ovary and concurrently occult in the thyroid. Is conservative treatment always advised?
Introduction: Struma ovarii is an ovarian teratoma, represented in more than 50% by thyroid tissue. Five percent of struma ovarii cases
have been proven to be malignant and, as in the thyroid gland, papillary thyroid carcinoma is the most common histotype arising in
struma ovarii. Because of the unusual occurrence of this tumor, its management and follow-up after pelvic surgery is still controversial.
Usually, total thyroidectomy followed by radioiodine treatment is the choice treatment in metastatic malignant struma ovarii, while these
procedures are still controversial in non-metastatic thyroid cancer arising in struma ovarii. Case Presentation: We report a female with follicular variant of papillary thyroid carcinoma arising in struma ovarii. After pelvic
surgery, thyroid morphofunctional examinations were performed and a single nodular lesion in the left lobe was discovered. The patient
underwent total thyroidectomy and histological examination showed a papillary carcinoma. Radioiodine-ablation of residual thyroid
tissue was performed and levothyroxine mildly-suppressive treatment was started. Conclusions: A more aggressive treatment should not be denied for malignant struma ovarii without any evidence, even when apparently
confined into the ovary. However, in selected cases, aggressive treatment may be advisable to decrease the risk of recurrence and to allow
an accurate follow-up
Corporate Social Responsibility Activities Through Twitter: From Topic Model Analysis to Indexes Measuring Communication Characteristics
The communication of corporate social responsibility (CSR) highlights the behavior of the business toward CSR and their framework of sustainable development (SD), thus helping policymakers understand the role businesses play with respect to the 2030 Agenda. Despite its importance, this is still a relatively underexamined and emerging topic. In our paper, we focus on what businesses communicate about CSR through social media and how this relates to the Sustainable Development Goals (SDGs). We identified the topics discussed on Twitter, their evolution over time, and the differences across sectors. We applied the structural topic model (STM) algorithm, which allowed us to estimate the model, including document-level metadata (time and sector). This model proved to be a powerful tool for topic detection and the estimation of the effects of time and sector on the discussion proportion of the topics. Indeed, we found that the topics were well identified overall, and the model allowed catching signals from the data. We derived CSR communication indexes directly from the topic model (TM) results and propose the use of dissimilarity and homogeneity indexes to describe the communication mix and highlight differences and identify clusters
L'impatto delle patologie gastrointestinali sul trattamento tiroxinico
Negli ultimi anni l’approccio alla terapia tiroxinica è mutato da una condizione di empirismo posologico a una fine calibrazione che consente di prevederne un dosaggio individualizzato. Il mancato raggiungimento del target terapeutico in corso di terapia con levotiroxina può derivare non solo da un inadeguato rapporto medico-paziente o dall’interazione
con altri farmaci, ma anche e soprattutto dalla presenza di patologie gastrointestinali concomitanti, frequentemente occulte. La terapia tiroxinica diviene così, oltre che strumento terapeutico, un possibile strumento diagnostico
A Bayesian approach for the identification of patient-specific parameters in a dialysis kinetic model
Hemodialysis is the most common therapy to treat renal insufficiency. However, notwithstanding the recent improvements, hemodialysis is still associated with a non-negligible rate of comorbidities, which could be reduced by customizing the treatment. Many differential compartment models have been developed to describe the mass balance of blood electrolytes and catabolites during hemodialysis, with the goal of improving and controlling hemodialysis sessions. However, these models often refer to an average uremic patient, while on the contrary the clinical need for customization requires patient-specific models. In this work, we assume that the customization can be obtained by means of patient-specific model parameters. We propose and validate a Bayesian approach to estimate the patient-specific parameters of a multi-compartment model, and to predict the single patient’s response to the treatment, in order to prevent intra-dialysis complications. The likelihood function is obtained by means of a discretized version of the multi-compartment model, where the discretization is in terms of a Runge–Kutta method to guarantee convergence, and the posterior densities of model parameters are obtained through Markov Chain Monte Carlo simulation. Results show fair estimations and the applicability in the clinical practice
A predictive index of intra-dialysis IDH. A statistical clinical data mining approach.
Intra-Dialysis Hypotension (IDH) is one of the main hemodialysis related complications, occurring in 25-30% of the sessions. The factors involved in the onset of hypotension in patients undergoing dialysis are due both to clinical conditions (e.g. presence of vascular or cardiac diseases, neuropathology, anemia) and treatment settings such as temperature of the dialysate, sodium concentration, buffer composition,
ultrafiltration rate, etc. The patient’s peculiar reaction to the treatment implies difficulties in preventing IDH episodes. This work explores the possibility to use a multivariate analysis of clinical data to quantify the risk to develop IDH at the beginning
of each session. The study is framed in the DialysIS project (Dialysis therapy between Italy and Switzerland) funded by INTERREG – Italy – Switzerland and Co-funded by European Union. Data referring to a total of 516 sessions performed on 70 adult patients undergoing dialysis treatment (50 patients enrolled at A. Manzoni Hospital Lecco, Italy and 20 patients at Regional Hospital of Lugano, Switzerland) were collected. Clinical prescriptions, hydration status, dialysis machine data and hematochemical data were recorded and stored in a unique
flexible structured MySQL® database. A statistical analysis was performed to find the potential risk factor related to IDH onset. IDH episodes were automatically detected during the monitored sessions, according to the literature criteria. Patients suffering from IDH in 2 or more sessions were classified as Hypotension Prone (HP), the others as Hypotension Resistant (HR). Initial values of potassium concentration [K+], systolic (SBP) and diastolic (DBP) blood pressure, and weight gain (ΔW) from the end of the previous treatment result to be statistically
different between the HP and HR groups.
A new index, J, was defined as a weighted patient-specific combination of these parameters and calculated for each session of each patient. The weight of the index coefficients can be dynamically adjourned based on the longitudinal analysis of [K+], SBP, DBP, and ΔW. The results reported in this paper were calculated based on a longitudinal analysis of a minimum of three sessions for each patient. The accuracy of the J index in predicting IDH events has been evaluated and quantified in terms of percentage number of predicted IDH events, with respect to the total number of IDHs.
Values of J index higher than 1 point out the risk of IDH onset. J allows the prediction of 100% of IDH episodes using 5 sessions, the 90% using 3 sessions. More specifically, at Lecco Hospital 43 IDH events were detected by the automatic system of which 100% and 95% were respectively predicted by the new index calculated using 5 or 3 sessions. Similarly, at Lugano Hospital 58 IDH were detected by the automatic system of which 100% and 87,5% were predicted using 5 or 3 sessions respectively. A longer longitudinal dataset will allow a higher matching of J to actual IDH episodes.
In conclusion, the evaluation of this new index at the beginning of the dialysis session prior to connecting the patient to the machine can provide the clinician with useful information about the risk for the patient to develop cardiovascular instabilities (IDH) during the treatment and can advise the physician about the need to modify the prescription
An in vitro strategy to assess mitigation of hazardous properties of engineered metal nanoparticles
The huge progress in the nanotechnology field has requested the production of increasingly
advanced engineered nanoparticles (NPs). In particular, metal-based advanced NPs are
widely used in several industrial applications. However, their potential effects on human
health during occupational exposure are still incompletely characterized thus far and
possible strategies to decrease their hazardous properties are not yet clearly defined. In this
project we are developing an in vitro approach to test the cytotoxic effects of metal-based
NPs, as derived from production lines or modified through coating with organic or inorganic
moieties. We have used two cell models widely employed in toxicological studies, the human
alveolar cell line A549 and the murine macrophage cell line RAW264.7, to avoid possible
limitations due to cell specific effects. Moreover, in order to evaluate the effectiveness of
mitigation approaches for NPs endowed with little acute cytotoxicity, additional endpoints,
alternative to viability, have also been assessed. Colloidal suspensions of Ag, TiO2 and ZrO2
NPs were tested as provided by industries or modified with SiO2 NPs or citrate used as
coating remediation agents. Heterocoagulation of opposite charged phases was applied in
order to promote the coating of pristine surfaces by modifying agents. Heterocoagulated sols
were obtained by ball milling sols of positive charged Ag, TiO2 and ZrO2 NPs with negative
charged SiO2 NPs or citrate ions. Modified samples, obtained by spray-drying and re-
dispersing in water the corresponding sols, were also obtained in order to compare
reactivity. Original and modified NPs were added to culture media starting from water
colloidal suspensions. Viability was determined with the resazurin method in a range of
doses from 2.5 to 80 nfg/cm2 (0.3125 to 20 g/cm2 for Ag NPs) of monolayer surface at three
experimental times (24, 48 and 72h). The expression of the inducible form of nitric oxide
synthase (Nos2), an indicator of macrophage activation and, hence, of pro-inflammatory
activity, was assessed with RT-PCR as an end-point alternative to viability.
Among the NPs tested, only Ag NP caused a significant loss of viability, with an IC50 of about
0.8 g/cm2 for Raw264.7 cells and 2.4 g/cm2 for A549 cells at the 24h-experimental time. In
a preliminary experiment, SiO2 NPs were demonstrated to have no significant effect on cell
viability. The comparison between original and SiO2-coated Ag NPs, performed in the same
experiment, suggested a coating-independent mitigation effect of bioreactivity exerted by the
spray drying procedure. However, once corrected for the actual Ag content of the spray-
dried powder, no significant difference was found in the IC50 values, indicating that neither
silica coating nor spray drying mitigate cytotoxicity. The effects on viability of original TiO2
and ZrO2 NPs were assessed using P25 Aeroxide TiO2 NPs as a reference material. These
materials did not affect significantly cell viability at any time point tested, so that it was not
possible to estimate IC50 values for either cell line. However, titania produced a clear-cut
induction of Nos2 expression in Raw264.7 cells, thus indicating their potential pro-
inflammatory activity. Citrate coating did not produce any significant attenuation of the
biological effect. In summary, these preliminary results showed no mitigating effect of the
surface modifications tested on the biological effects of the engineered NPs investigated.
However, the exploitation of this in vitro experimental strategy can be useful for the
preliminary assessment of the mitigation potential of surface modifications of both low-toxic
and high-toxic engineered NPs.
Supported by EU Grant NMP4-SL-2012-280716 (Sanowork Project
Alu-element insertion in an OPA1 intron sequence associated with autosomal dominant optic atrophy
Abstract
PURPOSE:
Autosomal dominant optic atrophy (ADOA) is the most common form of hereditary optic neuropathy caused by mutations in the optic atrophy 1 (OPA1) gene. It is characterized by insidious onset with a selective degeneration of retinal ganglion cells, variable loss of visual acuity, temporal optic nerve pallor, tritanopia, and development of central, paracentral, or cecocentral scotomas. Here we describe the clinical and molecular findings in a large Italian family with ADOA.
METHODS:
Routine ophthalmologic examination and direct sequencing of all coding regions of the OPA1 gene were performed. Further characterization of a new OPA1 gene insertion was performed by reverse transcription-PCR (RT-PCR) of RNA from patients and control subjects.
RESULTS:
We identified an Alu-element insertion located in intron 7 of OPA1 causing an in-frame deletion of exon 8 in 18 family members.
CONCLUSIONS:
The predicted consequence of this mutation is the loss of the guanosine triphosphatase (GTPase) activity of OPA1. Alu insertions have been reported in the literature as causing human genetic disease. However, this is the first report of a pathogenic OPA1 gene mutation resulting from an Alu insertion
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