148 research outputs found
Sustainability in the last mile online food delivery: an important contribution using the case study of “Glovo”
Treballs Finals del Màster en Oficial en Empresa Internacional / International Business, Facultat d'Economia i Empresa, Universitat de Barcelona, Curs: 2020-2021, Tutor: Guillermo Oliva GalvánThe online food delivery industry is one of the most promising industries worldwide, characterized by an increasing annual growth rate. In this context, last mile online food delivery platforms have particularly emerged and gained importance. Since last mile represents the most air polluting stage of the entire supply chain, it is worth to put particular attention on this last step. The aim of this Master thesis is to analyse the broader impacts of online food delivery considering economic, social and environmental issues, the so called “Triple Bottom Line”. Considering this as a new research field, new insights are gained through a qualitative case study research design based on “Glovo”, a company which has its main business, namely the last mile online food delivery, in the analysed sector. The results give interesting insights about the main challenges such companies have to deal with and potential sustainable business practices
VALUTAZIONE DELLA RISPOSTA UMORALE E CELLULO-MEDIATA CONTRO SARS-COV-2 EVOCATA DAL VACCINO PFIZER mRNA BNT162b2 IN PAZIENTI IMMUNOSOPPRESSI.
In questo lavoro di tesi è stata valutata la risposta immunitaria umorale e cellulo-mediata, in seguito alla somministrazione del vaccino a mRNA anti-COVID-19 (Pfizer mRNA BNT162b2), in pazienti trattati con farmaci immunosoppressi e con immunodeficienza comune variabile (CVID).
Dall’Unità di Reumatologia e Immunologia Clinica, dell’A.O. Spedali Civili di Brescia sono stati reclutati 38 pazienti, di cui 34 affetti da malattie reumatiche croniche (RDs), 4 da CVID e 11 persone sane (HC), utilizzate come controlli.
Tutti i pazienti con RDs erano sottoposti ad una terapia a base di corticosteroidi e/o trattamento immunosoppressivo e/o farmaci biologici; in particolare, 14 pazienti assumevano abatacept (ABA), 10 rituximab e 10 tocilizumab.
In primo luogo, è stato valutato il titolo anticorpale sia contro la proteina del nucleocapside (N) che della proteina Spike (S) di SARS-CoV-2 mediante immunodosaggio ad elettro chemiluminescenza. È stata analizzata la risposta immunitaria cellulo-mediata dei linfociti T CD4+ e CD4+-CD8+ mediante il test di rilascio dell’interferone- (IFN-) e valutata la produzione di chemochine indotte dall’IFN- (CXCL9 e CXCL10) e dalle cellule dell’immunità innata (CCL2, CXCL8 e CCL5), mediante l’uso di cytometric bead array method (CBA) a seguito di stimolazione con due pool di peptidi differenti della proteina S di SARS-CoV-2. Infine, mediante citofluorimetria, è stata studiata l’espressione di marcatori di attivazione precoce, come CD40L, CD137 e di citochine intracellulari, come IL-2, IFN- e IL-17, a seguito di stimolazione dei linfociti T con due pool di peptidi differenti della proteina S.
I principali risultati ottenuti sono stati: (i) una ridotta risposta anti-S nei pazienti trattati con ABA, ripristinata però dopo la terza dose vaccinale; (ii) una ridotta attivazione delle cellule T dovuta ad una riduzione di IFN- e chemochine (CXCL9 e CXCL10); (iii) una riduzione di cellule T CD8+ della memoria nei pazienti trattati con ABA; (iv) una significativa abilità dei pazienti trattati con ABA di sviluppare una risposta cellulo-mediata delle cellule T CD4+, se stimolate con antigeni derivati dalla proteina S di SARS-CoV-2.
Nonostante questo lavoro sia stato limitato dal basso numero di pazienti reclutati, l’esecuzione di numerose valutazioni effettuate a livello cellulare, ha contribuito a dimostrare il tipo di risposta immunitaria che i pazienti sottoposti a diverse terapie immunosoppressive sono stati in grado di generare a seguito della vaccinazione anti-COVID-19. La capacità di generare cloni di linfociti T CD4+ SARS-CoV-2 specifici in seguito alla vaccinazione, ha garantito a questi pazienti un’efficace protezione contro il virus. Inoltre, dal momento che, i pazienti trattati con ABA, dopo la somministrazione della terza dose di vaccino a mRNA anti-COVID-19 hanno acquisito la capacità di aumentare la risposta anticorpale, si può affermare che dosi ripetute di vaccino potrebbero essere necessarie al fine di ottimizzare la risposta immunologica in pazienti altamente vulnerabili.In this study, we analyzed T cell-mediated response after COVID-19 mRNA vaccine in immunosuppressed patients and patients with common variable immunodeficiency disease (CVID).
We enrolled 38 patients, from the Unit of Rheumatology and Clinical Immunology, of the A.O. Spedali Civili of Brescia, Italy, and 11 healthy sex- and age- matched controls (HC). Four patients were affected by CVID and 34 by chronic rheumatic diseases (RDs). All patients with RDs were treated by corticosteroid therapy and/or immunosuppressive treatment and/or biological drugs: 14 patients were treated with abatacept, 10 with rituximab and 10 with tocilizumab.
Total antibody titer to SARS-CoV-2 spike protein was assessed by electrochemiluminescence immunoassay, CD4+ and CD4+-CD8+ T cell-mediated immune response was analyzed by interferon- (IFN-) release assay, the production of IFN-γ-inducible (CXCL9 and CXCL10) and innate-immunity chemokines (CCL2, CXCL8 and CCL5) by cytometric bead array after stimulation with different spike peptides. The expression of CD40L, CD137, IL-2, IFN-γ and IL-17 on CD4 and CD8 T cells, evaluating their activation status, after SARS-CoV-2 spike peptides stimulation, was analyzed by intracellular flow cytometry staining.
The main findings were (i) a reduced anti-S response in ABA-treated group, restored after the third dose of vaccine; (ii) an impaired T cell activation, represented by a reduction of IFN-γ and related chemokines; (iii) a reduction of effector memory CD8+ T cells in ABA-treated group; (iiii) a significant ability of ABA treated group to mount a CD4 T cell response, when stimulated with spike derived antigens.
Our work was limited by the low number of patients enrolled but performing extended cellular assessments, contributed to explain which kind of immune response patients chronically exposed to different immunosuppressive regimen are able to generate in response to COVID-19 vaccination. The preserved ability to generate clones of CD4+ T lymphocytes specific for SARS-CoV-2 spike proteins represents the assurance of an effective protection of vaccination to SARS-CoV-2. Moreover, after the third dose of COVID-19 mRNA vaccine, ABA-treated patients acquired the capability to produce a strong antibody response, despite they maintained a significant reduction of CD8+ T response. All these data represent a critical message from laboratory research bench to clinical patients’ side, suggesting that repeated vaccine doses may be necessary to optimize the immunological response and to induce more robust serological responses in these high-risk vulnerable patients
Ozone therapy in dentistry: An overview of the biological mechanisms involved (Review)
At low medically‐relevant concentrations, ozone
serves as an oxidant with a wide spectrum of antimicrobial
activity and the ability to promote healing and reduce inflammation.
Despite providing therapeutic benefits in a range of
diseases, certain adverse effects and contraindications of ozone
treatment must be considered. These are primarily related to
toxicity from inhalation and systemic types of administration
and can be avoided by following relevant guidelines and
recommendations. Ozone therapy has been implemented in
a number of fields of dentistry and the most commonly used
formulations for the oral cavity are gaseous ozone, ozonized
water and ozonized oil. The biological mechanisms underlying
the molecular effects of ozone have been increasingly reported,
but currently remain largely unknown. The aim of the present
review was to provide an overview of the mechanisms involved
in ozone interaction with dental tissues. The present review
focused on relevant evidence regarding the effect of ozone on
dental tissues, including periodontal structures, dental cells,
enamel and dentine, considering in vitro studies in addition
to animal and human studies. A variety of biological mechanisms
acting through multiple biochemical target pathways
were reported to be responsible for the therapeutic effects of
ozone. The main beneficial effects of ozone occurred in the
following domains: antimicrobial activity, remineralization
and microstructural changes of hard dental tissues, immunomodulation
and biostimulation of dental and periodontal cells.
Additional research could provide further insights into the use
of ozone, increase its use for broader clinical applications and
assist in the selection of targeted protocols
Fluoride Exposure and ADHD: A Systematic Review of Epidemiological Studies
Background and objectives: Attention deficit hyperactivity disorder (ADHD) is a childhood-onset neurodevelopmental disorder characterized by two dimensions: inattentiveness and hyperactivity/impulsivity. ADHD may be the result of complex interactions between genetic, biological and environmental factors possibly including fluoride exposure. Materials and methods: A literature search was performed on 31 March 2023 in the following databases: PubMed, Embase and Web of Science. We defined the following inclusion criteria according to the PECOS statement: a healthy child and adolescent population (P), fluoride exposure of any type (E), comparison with low or null exposure (C), ADHD spectrum disorder (O), and ecological, cross-sectional, case-control and cohort studies (S). Results: We found eight eligible records corresponding to seven different studies investigating the effect of fluoride exposure on children and adolescents. One study had a cohort design and one a case-control one, while five were cross-sectional. Only three studies applied validated questionnaires for the purpose of ADHD diagnosis. As regards exposure assessment, levels of fluoride in urine and tap water were, respectively used in three and two studies, while two used both. Three studies reported a positive association with ADHD risk, all assessing exposure through fluoride levels. By using urinary fluoride, conversely, a positive correlation with inattention, internalizing symptoms, cognitive and psychosomatic problems was found in three studies, but no relation was found in the other one. Conclusions: The present review suggests that early exposure to fluoride may have neurotoxic effects on neurodevelopment affecting behavioral, cognitive and psychosomatic symptoms related to ADHD diagnosis. However, due to the heterogeneity of the studies included, current evidence does not allow to conclusively confirm that fluoride exposure is specifically linked to ADHD development
Selenium, zinc and copper content of foods consumed in an Italian community
This study aimed to determine the concentrations of selenium,
zinc and copper in foods generally composing the diet of Northern
Italy population in order to implement a database of the quantitative
content for each of the three trace elements, according to
food category intake. Food samples were collected from (small to
large) distribution markets in triplicates and trace elements determination
was performed with ICP-MS after sample mineralization.
We found the highest levels of selenium in meat (202g/kg),
fish and seafood (489), dry fruits (314) and legumes (220). The
level of zinc was higher in cereal products (11.7 mg/kg), meat
(28.4), dairy products (18.8), legumes (21.2) and dry fruits (37.8).
Finally, the highest concentration of copper was found in dry fruits
(14.9 mg/kg), legumes (6.2), sweets (4.1) and meat (3.7). Our findings
will allow to estimate dietary trace elements exposure which
could be useful for both toxicological and epidemiological studies
Selenium in humans: which is the safe range of intake?
Selenium in humans: which is the safe range of intake
A Path Relinking Method for the Joint Online Scheduling and Capacity Allocation of DL Training Workloads in GPU as a Service Systems
The Deep Learning (DL) paradigm gained remarkable popularity in recent years. DL models are used to tackle increasingly complex problems, making the training process require considerable computational power. The parallel computing capabilities offered by modern GPUs partially fulfill this need, but the high costs related to GPU as a Service solutions in the cloud call for efficient capacity planning and job scheduling algorithms to reduce operational costs via resource sharing. In this work, we jointly address the online capacity planning and job scheduling problems from the perspective of cloud end-users. We present a Mixed Integer Linear Programming (MILP) formulation, and a path relinking-based method aiming at optimizing operational costs by (i) rightsizing Virtual Machine (VM) capacity at each node, (ii) partitioning the set of GPUs among multiple concurrent jobs on the same VM, and (iii) determining a due-date-aware job schedule. An extensive experimental campaign attests the effectiveness of the proposed approach in practical scenarios: costs savings up to 97% are attained compared with first-principle methods based on, e.g., Earliest Deadline First, cost reductions up to 20% are obtained with respect to a previously proposed Hierarchical Method and up to 95% against a dynamic programming-based method from the literature. Scalability analyses show that systems with up to 100 nodes and 450 concurrent jobs can be managed in less than 7 seconds. The validation in a prototype cloud environment shows a deviation below 5% between real and predicted costs
Cadmium, lead and mercury levels in cerebrospinal fluid and risk of amyotrophic lateral sclerosis – A case-control study.
Cadmium, lead and mercury levels in cerebrospinal fluid and risk of amyotrophic lateral sclerosis – A case-control study
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