693 research outputs found
L’adattamento italiano del Group Questionnaire (GQ): risultati preliminari in gruppi di training universitario.
No full textLa comprensione del processo clinico e terapeutico nei gruppi, l’elaborazione concettuale sui costrutti della relazione terapeutica, l’indagine sulla sovrapposizione concettuale (e statistica) dei costrutti Clima di gruppo, Coesione ed Alleanza sono alla base della proposta del Group Questionnaire - GQ (Burlingame, McClendon, Alonso, 2011), self-report di 30 item, che fornisce informazioni sulla qualità delle relazioni in gruppo.
Il Group Questionnaire - GQ si differenzia dagli strumenti precedentemente usati perché fondato su una teoria unificata della relazione gruppale (Johnson et al, 2005, 2008; Bormann and Strauss, 2007; Bakali et al, 2008), che individua un modello a tre fattori: Legame positivo, Capacità di lavoro positiva e Relazione negativa. Inoltre fornisce informazioni specifiche su quanto le relazioni in gruppo (membro-membro, membro-leader e membro-gruppo) siano relativamente forti o deboli.
Saranno presentati i risultati preliminari dell’adattamento italiano del GQ, somministrato a 100 soggetti che hanno partecipato ai gruppi di elaborazione sull’identità professionale, organizzati all’interno del training formativo per gli studenti delle Lauree Magistrali in Psicologia Clinica (5 gruppi, durata 8 incontri).
Sono state considerate due rilevazioni (3 e 6 incontro). Insieme al GQ sono stati somministrati CALPAS_G (Alleanza) e GMLCS_G (Coesione). Verrà valutata la validità convergente e la coerenza interna del GQ
FORMATION OF HIGH-QUALITY STORAGE CAPACITOR DIELECTRICS BY IN-SITU RAPID THERMAL REOXIDATION OF SI3N4 FILMS IN N2O AMBIENT
No full textThis letter reports on a novel reoxidation technique for SiO2/Si3N4 (ON) stacked films by using N2O as oxidant. Effect of in-situ rapid thermal N2O reoxidation (RTNO) on the electrical characteristics of thin ON stacked films are studied and compared with those of in-situ rapid thermal O2 reoxidation (RTO). Prior to reoxidation, the Si3N4 film was deposited by rapid thermal chemical vapor deposition (RT-CVD) using SiH4 and NH3. Results show that RTNO of the Si3N4 films significantly improves electrical characteristics of ON stacked films in terms of lower leakage current, suppressed charge trapping, reduced defect density and improved time-dependent-dielectric-breakdown (TDDB), as compared to RTO of the Si3N4 films
EFFECTS OF GROWTH TEMPERATURE ON TDDB CHARACTERISTICS OF N2O-GROWN OXIDES
No full textIn this paper, effects of oxide growth temperature on time-dependent dielectric breakdown (TDDB) characteristics of thin (115 angstrom) N2O-grown oxides are investigated and compared with those for conventional O2-grown SiO2 films with identical thickness. Results show that TDDB characteristics of N2O oxides are strongly dependent on the growth temperature and, unlike conventional SiO2, TDDB properties are much degraded for N2O oxides with an increase in growth temperature. Large undulations at the Si / SiO2 interface, caused by locally retarded oxide growth due to interfacial nitrogen, are suggested as a likely cause of degradation of TDDB characteristics in N2O oxides grown at higher temperatures
HIGH-FIELD BREAKDOWN IN THIN OXIDES GROWN IN N2O AMBIENT
No full textWe report a detailed study of time-dependent dielectric breakdown (TDDB) in N2O-grown thin (47-120 angstrom) oxides. A significant degradation in breakdown properties (such as charge-to-breakdown, breakdown field) was observed in N2O oxides with increasing oxide growth temperature; a strikingly different dependence than that in pure oxides. A physical model based on undulations at the Si/SiO2 interface is discussed to account for the degradation of breakdown properties for higher N2O oxidation temperature. Accelerated breakdown in N2O oxides for higher operating temperatures and higher oxide fields as well as thickness dependence of TDDB are studied under both polarities of injection. These dependencies are similar to the reported data on pure oxides. Breakdown under unipolar and bipolar stress in N2O oxides is compared with dc breakdown. Unlike the case of pure oxides, an asymmetric improvement in time-to-breakdown under positive versus negative gate unipolar stress is observed, which is attributed to charge detrapping behavior in N2O oxides. A dramatic reduction in time-to-breakdown of N2O oxide is observed under bipolar stress when the thickness is scaled below 60 angstrom. A physical model, based on the thickness dependence of trapped hole centroid, is suggested to explain this behavior. Overall, our results indicate that N2O oxides are expected to show improved breakdown properties than pure SiO2 Over a wide range of operating temperatures, electric fields, oxide thicknesses, as well as under ac stress
Improved current drivability and gate stack integrity using buried SiC layer for strained Si/SiGe channel devices
No full textGq Protein-Coupled Membrane-Initiated Estrogen Signaling Rapidly Excites Corticotropin-Releasing Hormone Neurons in the Hypothalamic Paraventricular Nucleus in Female Mice
No full textCRH neurons in the hypothalamic paraventricular nucleus (PVN) play a central role in regulating the hypothalamus-pituitary-adrenal (HPA) axis and are directly influenced by 17β-estradiol (E2). Although compelling evidence has suggested the existence of membrane-associated estrogen receptors (mERs) in hypothalamic and other central nervous system neurons, it remains unknown whether E2 impacts CRH neuronal excitability through this mechanism. The purpose of the current study is to examine the existence and function of mER signaling in PVN CRH neurons. Whole-cell recordings were made from CRH neurons identified by Alexa Fluor 594 labeling and post hoc immunostaining in ovariectomized female mice. E2 (100nM) rapidly suppressed the M-current (a voltage-dependent K(+) current) and potentiated glutamatergic excitatory postsynaptic currents. The putative Gq-coupled mER (Gq-mER) characterized in hypothalamic proopiomelanocortin neurons initiates a phospholipase C-protein kinase C-protein kinase A pathway; therefore, we examined the involvement of this pathway using selective inhibitors. Indeed, the ER antagonist ICI 182780 and inhibitors of Gq-phospholipase C-protein kinase C-protein kinase A blocked E2's actions, suggesting dependence on the Gq-mER. Furthermore, STX, a selective ligand for the Gq-mER, mimicked E2's actions. Finally, to examine the in vivo effect of Gq-mER activation, E2 or STX injection increased c-fos expression in CRH neurons in the PVN, suggesting CRH neuronal activation. This corresponded to an increase in plasma corticosterone. We conclude that the Gq-mER plays a critical role in the rapid regulation of CRH neuronal activity and the HPA axis. Our findings provide a potential underlying mechanism for E2's involvement in the pathophysiology of HPA-associated mood disorders.Peer reviewe
Integration of Dual Channels MOSFET on Defect-Free, Tensile-Strained Germanium on Silicon
No full textTensile-strained germanium CMOS integration on silicon
No full text10.1109/LED.2007.909836IEEE Electron Device Letters28121117-1119EDLE
Investigation of mouse mutant Gq proteins through BRET assay
No full textreservedI recettori accoppiati a proteine G (GPCR) costituiscono la più ampia famiglia di bersagli farmacologici e regolano numerosi processi fisiologici e patologici attraverso le proteine G eterotrimeriche. L’inibizione di questi trasduttori rappresenta una strategia potente per indagare in maniera causale le reti di segnalazione complesse e spesso promiscue tipiche dei GPCR. Il depsipeptide FR900359 (FR) è un inibitore potente che blocca lo scambio nucleotidico sulla subunità Gα, ma la sua selettività è limitata alle sottofamiglie Gq, G11 e G14. Poiché lo sviluppo di inibitori altrettanto selettivi per le altre famiglie di proteine G si è rivelato complesso, la specificità intrinseca di FR può essere sfruttata nella creazione di un set di strumenti chemogenetici, in cui siti di legame ingegnerizzati rendono tutte le famiglie di proteine G direttamente controllabili da questo composto.
Il primo passo verso lo sviluppo di questo strumento è stato il design razionale di mutanti di Gαq resistenti a FR ma con proprietà di tipo wild-type, requisito fondamentale per potenziali applicazioni in vivo. Questa strategia è stata inizialmente implementata e ampiamente caratterizzata per Gαq di Drosophila melanogaster (DGαq) nella tesi di dottorato di Judith Alenfelder, condotta nel laboratorio della Prof.ssa Evi Kostenis. Questi studi hanno identificato mutanti che in vitro mostravano cinetiche di disattivazione più lente, dovute a una ridotta sensibilità alle proteine regolatrici della segnalazione G (RGS) umane, senza tuttavia compromettere la segnalazione a valle. La loro applicazione con successo in Drosophila ha confermato la validità in vivo e ne ha evidenziato il potenziale. Sulla base di questi risultati, le stesse mutazioni sono state introdotte nella Gαq murina (mGαq), un modello identico alla proteina Gαq umana.
La presente tesi si articola in due parti, entrambe volte ad approfondire il lavoro di Alenfelder mediante l’uso di tecniche BRET. La prima parte indaga le cinetiche di disattivazione dei mutanti, con l’obiettivo di verificare se i rallentamenti osservati nei mutanti DGαq siano mantenuti anche nella controparte murina e, in tal caso, se riflettano una diversa affinità verso le proteine RGS. La seconda parte analizza i meccanismi che contribuiscono all’attività basale dei mutanti mGαq, concentrandosi sullo scambio nucleotidico spontaneo e sull’attività GTPasica intrinseca.
I risultati hanno mostrato che le cinetiche di disattivazione dei mutanti rispetto al wild type mGαq erano meno marcate rispetto a quelle di DGαq, producendo differenze non biologicamente rilevanti. Poiché le cinetiche di disattivazione riflettono l’attività GTPasica intrinseca, questo dato indica che tale componente dell’attività basale non subisce alterazioni significative, rispondendo così parzialmente alla domanda posta sull’attività basale. Al contrario, il contributo dello scambio spontaneo GDP/GTP non ha potuto essere valutato nelle condizioni sperimentali stabilite.G protein-coupled receptors (GPCRs) constitute the largest family of drug targets and regulate diverse physiological and pathological processes through heterotrimeric G proteins. Inhibiting these transducers represents a powerful strategy to study the complex and promiscuous signaling networks typical of GPCRs. The depsipeptide FR900359 (FR) is a potent inhibitor that blocks nucleotide exchange on the Gα subunit, yet its selectivity is limited to the Gq, G11, and G14 subfamilies. Since the development of equally selective inhibitors for other G protein families has proven challenging, FR’s intrinsic specificity can be exploited instead in a chemogenetic-like toolbox, where engineered FR binding sites render all G protein families directly controllable by this compound.
The first step toward developing this toolbox was the rational design of Gαq mutants resistant to FR while retaining wild-type properties, a prerequisite for potential in vivo applications. This strategy was first implemented and extensively characterized for Drosophila melanogaster Gαq (DGαq) in the PhD thesis of Judith Alenfelder, conducted in the laboratory of Prof. Evi Kostenis. These studies identified mutants with slower deactivation kinetics in vitro, reflecting reduced sensitivity to human RGS proteins, yet without impairing downstream signaling. Their successful use in Drosophila confirmed their applicability in vivo and highlighted their potential. Based on these results, the same mutations were subsequently introduced into murine Gαq (mGαq), a model identical to human Gαq.
This thesis is divided into two parts, both of which build on Alenfelder’s work by further characterizing mGαq using BRET techniques. The first part investigates the deactivation kinetics of the mutants, with the aim of determining whether the slower kinetics observed in DGαq mutants are also present in the murine counterpart and, if so, whether they reflect altered affinity toward RGS proteins. The second part addresses the mechanisms contributing to the basal activity of mGαq mutants, focusing on spontaneous nucleotide exchange and intrinsic GTPase activity.
The results showed that the deactivation kinetics of mGαq mutants were less pronounced than in DGαq, leading to differences that were not biologically relevant. Since deactivation kinetics reflect intrinsic GTPase activity, this finding indicates that this component of basal activity is not altered in a biologically relevant way, thereby partially addressing the overall question on basal activity. However, the contribution of spontaneous GDP/GTP exchange could not be assessed under the established experimental conditions
Italian adaptation of the Group Questionnaire: Validity and factorial structure
No full textThe Group Questionnaire (GQ) is a measure recently developed by Krogel et al. (2013) for the evaluation of the therapeutic relationship in group. The GQ identifies a three-factor model of the relationship that allows to measure quality (Positive Bonding, Positive Working and Negative Relationship) and structure (member-member, member-leader and member-group), dimensions in group. This work shows the results of a first study on the Italian validation of the GQ. In this study the GQ was administered to 536 subjects from 32 non-clinical groups of undergraduate students. The cross-cultural validity of the GQ in the Italian population has been examined by comparing the psychometric properties and equivalence in factor structure and scores of the Italian GQ with the original American version. Multilevel confirmatory factor analysis was used to examine both the between- and within-group structures. Data concerning reliability and validity of GQ and the results for different SEM in Multilevel CFA confirm the three factors structure of the GQ. Data from the Italian population have a good fit with the original proposed model. Finally, we discuss the importance of an instrument like GQ, short but consistent, for the evaluation of the therapeutic relationship in clinical and training group
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