1,720,964 research outputs found
Differenze Individuali nella learning agility in ambito lavorativo: sviluppo e preliminare validazione di un nuovo strumento di misura. Uno studio mixed methods
No full textLa complessità dell'attuale contesto lavorativo richiede a leader e professionisti di apprendere nuove skills e di essere adattabili e aperti al cambiamento. Sono richieste nuove abilità e nuovi mindset e la disponibilità di strumenti psicometrici validi con cui valutarle è diventata strategica per le organizzazioni. Negli ultimi venti anni il concetto di learning agility è stato molto utilizzato nei sistemi di talent management come indicatore della capacità di apprendere dall'esperienza. Nel mondo accademico solo recentemente si è iniziato a studiare il concetto e la mancanza di una definizione condivisa ha limitato la disponibilità di strumenti di misura validi e comparabili. La ricerca psicometrica in questo ambito è quindi necessaria per assicurare strumenti affidabili e rigorosi di valutazione del costrutto. La presente ricerca intende rispondere a questo gap sviluppando e validando uno strumento di misura delle differenze individuali di learning agility utilizzabile in ambito lavorativo. Più in generale, la ricerca intende esplorare e comprendere le esperienze di apprendimento di manager e lavoratori in un contesto lavorativo di continuo cambiamento e incertezza. Per sviluppare e validare lo strumento è stato utilizzato uno studio multifase e mixed methods, strutturato in: 1) studio esplorativo qualitativo attraverso interviste e focus group per valutare e validare la lista preliminare di item; 2) studio quantitativo per definire la struttura fattoriale, l’invarianza di misura, attendibilità e validità nomologica della scala. La scala è stata validata su un campione di manager e lavoratori di paesi del Centro-Est Europa, Italia ed Egitto. La scala ha mostrato soddisfacente validità di contenuto, costrutto e validità nomologica.
La scala finale di 11 items fornisce a ricercatori e professionisti del settore HR una misura rigorosa, concisa e concreta da integrare nei sistemi di valutazione e sviluppo del personale. Lo studio presenta inoltre e discute future direzioni di ricerca e implicazioni pratiche.The present research flows from the unprecedented complexity and unpredictability of today’s business and working environment that require employees and leaders to constantly learn new skills, be adaptable and open to embracing change. Over the past two decades, the construct of learning agility has been extensively used in talent management systems as an individual indicator of the ability to learn from experiences and readiness to change. Although the concept has played a significant role in organizations and practitioners’ world, academics only recently directed their attention to the concept. Moreover, the lack of consensus in terms of the conceptual definition of learning agility has limited the full availability of valid and comparable psychometric tools. Psychometric research in this field is then imperative to ensure reliable and consistent measures of individual differences in learning agility.
To fill this gap, the present research aims at developing and validating a new scale to measure learning agility at work. More broadly, the research intends to explore and understand in depth the experiences of employees and managers about learning and dealing with change in complex and uncertain working environments.
The dissertation provides a rigorous analysis and systematic review of the extant literature about learning agility and its application to talent management (TM). Our findings revealed that a scientific approach to the construct remained limited and that learning agility is becoming a multidimensional construct with similarities and connections with other psychological constructs such as learning goal orientation, self-awareness, and resilience in the workplace. For the purposes of the research, we designed a multiphase, mixed methods study. Specifically, the present research project consists of two main phases: study 1) an exploratory qualitative study by means of interviews and focus groups to assess and validate the provisional items’ list and content; study 2) an extensive quantitative study for defining the factor structure, factorial invariance, reliability, and nomological validity of the scale. In addition, a secondary qualitative data analysis was embedded in the mixed methods design to investigate senior managers’ experiences and perspectives about learning and dealing with change in real working situations. The studies are based on independent samples of professionals and managers working in twelve banking companies, located in Central-Eastern European countries (Albania, Bosnia and Herzegovina, Croatia, Hungary, Moldova, Romania, Serbia, Slovakia, Slovenia, Ukraine), Italy, Egypt.
Our findings illustrated a final scale of eleven items, entitled the Learning Agility at Work (LAW) scale. A two-factor solution was identified; specifically, the extracted factors were named as follows: 1) Learning Mindset - it describes people who are interested in intentionally developing their competencies and who consider any experience as an opportunity for growing; 2) Adaptation to Change- it describes people who can positively adapt to changes, bounce back from setbacks and are quick and flexible to embracing new ideas and approaches. Although the LAW scale is in the initial stage of development, we provide evidence of its reliability and nomological validity. Scholars and practitioners can use the instrument to investigate individual differences in learning agility in managerial and nonmanagerial roles. Furthermore, our study contributes to the literature by advancing a novel proposition about the conception of learning agility. In comparison with the traditional definition of learning agility -as the ability to learn from experiences-, our study posits a new two-dimensional model that comprises a dynamic interaction between motivation for learning, and adaptation to change. Directions for future research are discussed along with implications for organizations
Emerging strategies for selective targeting in therapeutic approaches against gliomas
No full textIl glioblastoma multiforme (GBM) è tra i tumori cerebrali più aggressivi, generalmente compare in età adulta ed è caratterizzato da eterogeneità cellulare e diverse alterazioni genetiche (Louis DN, 2016). La terapia standard consiste in una combinazione di chirurgia, radioterapia e chemioterapia. Nonostante l’aggressività dei trattamenti, non esiste ancora una cura definitiva e il tasso medio di sopravvivenza è di soli 14,6 mesi (Wilson TA, 2014). Il farmaco di elezione nel trattamento del glioblastoma è la temozolomide (TMZ). La TMZ è un agente alchilante e viene utilizzato da solo o in combinazione con la radioterapia (Zhang J, 2012) ma, a causa dell’insorgenza di resistenza terapeutica, è un farmaco in grado soltanto di prolungare l’aspettativa di vita. Uno dei fattori responsabili dell’insorgenza di chemio-resistenza è l’aumento dell’attività dell’enzima O(6)-methylguanine-DNA-methyltransferase (MGMT), deputato alla riparazione dei danni al DNA provocati da TMZ (Fan CH, 2013). L’insorgenza e lo sviluppo del glioblastoma sono legati a diverse alterazioni molecolari dovute a meccanismi genetici ed epigenetici; pertanto le modificazioni nel processo apoptotico potrebbero non solo contribuire allo sviluppo del tumore, ma anche allo sviluppo di resistenza verso la classica terapia genotossica (Adamson C, 2009). I microRNAs, piccole molecole di RNA non codificante, giocano un ruolo chiave nella sopravvivenza cellulare, proliferazione, angiogenesi, metastasi e nello sviluppo di un fenotipo maligno nelle cellule di glioma. La tumorigenesi è pertanto il risultato del disequilibrio tra microRNA oncogeni (oncomiRNA) e miRNA soppressori tumorali, entrambi capaci di regolare l’espressione genica a livello post-trascrizionale attraverso la repressione della traduzione o la degradazione del mRNA bersaglio. Per esempio, gli oncogeni miR-155 e miR-221, sono molto espressi nel glioblastoma e riducono l’espressione di molti geni associati alla proliferazione delle cellule cancerose, all’apoptosi, all’invasività e alla chemioresistenza (Liu Q, 2015; Xie Q, 2014; Zhang CZ, 2010; Shea A, 2016). La comprensione della patogenesi del glioma permetterebbe quindi di identificare nuovi bersagli terapeutici e di sviluppare nuovi approcci volti anche al potenziamento delle attuali terapie e/o a limitare la crescita del tumore, così come a ridurne la resistenza. Lo scopo di questa tesi è stato quello di studiare nuovi possibili approcci terapeutici in grado di inibire la crescita delle cellule tumorali, indurre la morte cellulare per apoptosi e sensibilizzare le cellule di glioblastoma al trattamento con temozolomide e/o potenziarne l’attività. Per questo studio sono state utilizzate le cellule umane di glioblastoma U251 e T98G, queste ultime resistenti alla TMZ; in seguito a trattamento combinato con (i) temozolomide e corilagina, un’interessante tannino estratto da piante della famiglia delle Phillantaceae, e (ii) con temozolomide e PNA anti-miR-155 e anti-miR-221, sono stati studiati gli effetti su alcuni meccanismi molecolari, tra i quali apoptosi, proliferazione e migrazione cellulare. La corilagina (COR) presenta proprietà antiossidanti, antinfiammatorie e antitumorali ed è stato dimostrato che è capace di interferire con l’anti-apoptotico NF-kB (Gambari R, 2012; Dong XR, 2010) e di indurre apoptosi in cellule tumorali (Jia L, 2013, Ming Y, 2013; Gu Y, 2016). Pertanto la corilagina potrebbe essere una molecola potenzialmente attiva nel trattamento del glioblastoma. Inizialmente, mediante studi di docking, è stato dimostrato che la corilagina è in grado di ridurre i livelli di NF-kB inibendo la sua interazione con il DNA. Dopo trattamento con COR, la proliferazione delle cellule U251 e T98G è risultata ridotta e soprattutto si è visto un aumento dello stato di apoptosi. Molto interessante è l’effetto sulle cellule resistenti alla TMZ, T98G, che quando trattate con entrambi COR e TMZ mostrano un livello di apoptosi maggiore rispetto al trattamento singolo con corilagina o temozolomide. Questo è probabilmente legato al fatto che la corilagina, ma
soprattutto la corilagina combinata alla TMZ, sembrano ridurre l’espressione di MGMT e indurre l’attivazione della caspasi-3 (CASP-3); inoltre la corilagina si è dimostrata attiva anche nell’inibizione della migrazione cellulare, in particolare nel trattamento combinato. Per quanto riguarda i microRNA e il loro utilizzo come bersagli terapeutici, in questa tesi sono stati presi in considerazione i PNA anti-miR-155 e anti-miR-221. Questi microRNA sono stati selezionati da una lunga lista di microRNA alterati nel glioblastoma e che sembrano avere come target l’RNA messaggero della caspasi-3, un importante fattore coinvolto nel processo apoptotico. I risultati ottenuti dalle analisi Bio-Plex e dal saggio delle caspasi 3/7, dopo trattamento delle linee cellulari di glioma con i PNA R8-PNA-a155 e R8-PNA-a221, hanno
confermato l’ipotesi che la CASP-3 è un gene target del miR-155 e del miR-221. Molto recentemente, nel nostro gruppo di ricerca, è stato dimostrato che R8-PNA-a221 ha effetti pro-apoptotici in cellule di glioma (Brognara E, 2016); così, abbiamo investigato anche gli effetti del R8-PNA-a155 sia nelle cellule U251 che T98G. I dati ottenuti hanno dimostrato che entrambi i PNA sono selettivi nel colpire il relativo microRNA e sono capaci di indurre apoptosi in entrambi i modelli cellulari di glioma studiati. Dal momento che gli oncomiRNA promuovono la crescita e la sopravvivenza cellulare, abbiamo indagato se, nelle cellule T98G resistenti alla TMZ, combinando il trattamento con TMZ e PNA si riuscivano ad ottenere risultati migliori rispetto ai singoli trattamenti. Il co-trattamento con R8-PNA-a221 o R8-PNA-a155 ha indotto apoptosi nelle cellule T98G a livelli più elevati rispetto ai livelli ottenuti con la somministrazione del solo PNA; un effetto simile è stato osservato anche per quanto riguarda l’apoptosi legata all’attivazione della caspasi-3. In conclusione, i risultati riportati in questa tesi di dottorato dimostrano che l’induzione di
apoptosi, potrebbe essere un modo efficiente per modulare la progressione del cancro e la resistenza al farmaco. Con questa ricerca, quindi, abbiamo dimostrato che l’utilizzo di composti naturali o sintetici, come la corilagina o i PNA rispettivamente, potrebbe essere un’efficace strategia per potenziare l’attività della temozolomide e per rendere le cellule di glioma resistenti più sensibili all’effetto apoptotico da essa indotto.Glioblastoma multiforme (GBM) is a lethal malignant brain tumor in adulthood. The standard treatment consists of surgery,radiotherapy and chemotherapy. Nevertheless, the mean patient survival time reaches only 14.6 months. The first line drug in GBM treatment is the alkylating agent temozolomide (TMZ),but drug-resistance is often an issue due to several mechanisms such as the enhanced activity of MGMT, a DNA repair enzyme, and microRNAs. Many molecular changes involving genetic and epigenetic mechanisms can lead to gliomagenesis; thus,modifications in the apoptotic pathways may not only contribute to the tumor development,but also to the resistance towards classical therapeutic genotoxic approaches. MicroRNAs (miRNAs), play a pivotal role in the development of a malignant phenotype of glioma cells;and tumorigenesis occurs as the result of imbalances between oncomiRNAs and tumor-suppressor miRNAs, both acting as gene regulators at post-transcriptional level by either repressing translation or degrading the target mRNA. The oncomiRNAs miR-155 and miR-221 are significantly elevated in GBM,downregulating multiple genes associated with cancer cell proliferation, apoptosis, invasiveness and drug resistance.
The aim of this PhD thesis was to develop novel possible therapeutic interventions able to inhibit the tumor cells growth,as well as induce apoptotic cell death by sensitizing GBM cells to TMZ treatment and/or potentiating its activity. Therefore, human U251 and TMZ-resistant T98G glioma cells were studied combining: (i) the treatment with TMZ and corilagin, an interesting tannin extracted from plants of the Phillantus family, and (ii) TMZ with anti-miR-221 and anti-miR-155 PNAs.
Corilagin (COR) is known to exhibit several activities,interfere with the anti-apoptotic NFkB and to induce cancer cell apoptosis,representing a potential antitumor molecule. Docking studies demonstrated that COR is able to suppress the level of NFkB by preventing its ability to bind with DNA. Upon COR treatment,U251 and T98G glioma cells showed a reduction in their proliferation, but most importantly showed increased apoptosis. Interestingly, when T98G cells were co-treated with TMZ plus COR,they reached a level of apoptosis higher than that with TMZ or COR alone. This is probably related to the decrease of MGMT mRNA expression and the activation of caspase-3 (CASP-3), an important factor involved in the apoptosis pathway;moreover,COR demonstrated to be active at inhibiting cell migration, particularly when combined with TMZ.
Peptide nucleic acids (PNAs) were used by this thesis to modulate miR-155 and miR-221 expression; these miRNAs were selected from a list of miRNAs dysregulated in GBM,since they were predicted to target CASP-3 mRNA. This hypothesis was confirmed by the Bio-Plex analysis and by the Caspase 3/7 assay, after treatment of glioma cells with PNAs R8-PNA-a155 and R8-PNA-a221. Recently,it was demonstrated that R8-PNA-a221 has pro-apoptotic effects in glioma cells; thus,also the effect of R8-PNA-a155 was investigated on both U251 and T98G cells. The obtained data showed that both PNAs are selective in targeting their relative miRNA and that they induce apoptosis in both the glioma cell line models under study. In TMZ-resistant T98G cells, combining TMZ with PNAs could have a greater effect than single treatments. Co-administration of R8-PNA-a221 or R8-PNA-a155 induced apoptosis of TMZ-treated T98G cells at a level higher than that obtained following singular administration of R8-PNA-a221 or R8-PNA-a155; similar was the effect observed on apoptosis involving CASP-3 activation.
In conclusion,the results reported in this PhD thesis demonstrate that apoptosis induction could be an efficient way to modulate the progression of cancer and the drug resistance. Moreover, using natural compounds or synthetic agents, such as corilagin and PNAs,respectively,could constitute an efficient and powerful strategy to potentiate TMZ activit
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Full text link“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Full text linkWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Phloridzin derivatives inhibiting proinflammatory cytokine expression in human cystic fibrosis IB3-1 cells
No full textCystic Fibrosis (CF) is the most diffuse autosomal recessive genetic disease present in caucasian people. A persistent recruitment of neutrophils in the bronchi of CF patients contributes to exacerbate the airway tissue damage, suggesting the importance of modulating the expression of chemokines during the patient management. The identification of innovative anti-inflammatory drugs is considered a therapeutic target to prevent the progressive tissue deterioration1. Phloridzin, isolated from Malus domestica by a selective Molecular Imprinting extraction, and its structural analogues, Phloridzin eptaproprionate (F1) and Phloridzin tetraproprionate (F2)2, have been firstly investigated to discover their ability in reducing mainly IL-6 and IL-8 expression, released from CF cells under the control of the NF-kB Transcription Factor (TF), in human CF bronchial epithelial cells (IB3-1) stimulated with TNF-α. Among all the derivatives tested, F2 was the most interesting, demonstrating inhibitory effects also on the expression and production of different cytokines involved in CF inflammation processes, including RANTES, VEGF, GM-CSF, IL-12, G-CSF, MIP-1b, IL-17, IL-10 and IP-10, without any correlated anti- proliferative and pro-apoptotic effects
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