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1.
Five studies examined the hypotheses that when people experience positive affect, those low in self-esteem are especially likely to dampen that affect, whereas those high in self-esteem are especially likely to savor it. Undergraduate participants' memories for a positive event (Study 1) and their reported reactions to a success (Study 2) supported the dampening prediction. Results also suggest that dampening was associated with worse mood the day after a success (Study 2), that positive and negative affect regulation are distinct, that self-esteem is associated with affect regulation even when Neuroticism and Extraversion are controlled (Studies 3 and 4), and that self-esteem may be especially important for certain types of positive events and positive affect regulation (Study 5). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
2.
Progressive Transmission of Vector Map Data over the World Wide Web 总被引:17,自引:0,他引:17
Within distributed computing environments, access to very large geospatial datasets often suffers from slow or unreliable network connections. To allow users to start working with a partially delivered dataset, progressive transmission methods are a viable solution. While incremental and progressive methods have been applied successfully to the transmission of raster images over the World Wide Web, and, in the form of prototypes, of triangular meshes, the transmission of vector map datasets has lacked a similar attention. This paper introduces a solution to the progressive transmission of vector map data that allows users to apply analytical GIS methods to partially transmitted data sets. The architecture follows a client-server model with multiple map representations at the server side, and a thin client that compiles transmitted increments into a topologically consistent format. This paper describes the concepts, develops an architecture, and discusses implementation concerns. 相似文献
3.
Its more refined congestion control mechanisms, also based on the estimation of round trip delays, allow TCP Vegas to outperform the more widespread TCP Reno congestion control, based only on the packet loss detection, in a number of network environments. However, these mechanisms make TCP Vegas less aggressive with respect to TCP Reno; thereby TCP Vegas sources show high weakness in taking the available bandwidth when competing with other TCP Reno sources. This is a major reason that hinders the spread of TCP Vegas among Internet users. In this work, after a preliminary analytic study about the limits of TCP Vegas in mixed network environments, we describe a new adaptive mechanism for TCP Vegas, called TCP NewVegas, designed in order to improve its performance even in heterogeneous network scenarios. The large number of simulations, presented in this paper, show that TCP NewVegas guarantees good performance even in mixed network environments, without canceling the desirable features (e.g. fairness) that TCP Vegas exhibits in homogeneous environments. 相似文献
4.
Benedetta Chianucci Alice Grossi Gianluca DellOrso Elena Palmisani Marina Lanciotti Paola Terranova Filomena Pierri Michela Lupia Luca Arcuri Marica Laurino Isabella Ceccherini Fabian Beier Carlo Dufour Francesca Fioredda Maurizio Miano 《International journal of molecular sciences》2022,23(23)
In recent years, the knowledge about the immune-mediated impairment of bone marrow precursors in immune-dysregulation and autoimmune disorders has increased. In addition, immune-dysregulation, secondary to marrow failure, has been reported as being, in some cases, the most evident and early sign of the disease and making the diagnosis of both groups of disorders challenging. Dyskeratosis congenita is a disorder characterized by premature telomere erosion, typically showing marrow failure, nail dystrophy and leukoplakia, although incomplete genetic penetrance and phenotypes with immune-dysregulation features have been described. We report on a previously healthy 17-year-old girl, with a cousin successfully treated for acute lymphoblastic leukemia, who presented with leukopenia and neutropenia. The diagnostic work-up showed positive anti-neutrophil antibodies, leading to the diagnosis of autoimmune neutropenia, a slightly low NK count and high TCR-αβ+-double-negative T-cells. A next-generation sequencing (NGS) analysis showed the 734C>A variant on exon 6 of the TINF2 gene, leading to the p.Ser245Tyr. The telomere length was short on the lymphocytes and granulocytes, suggesting the diagnosis of an atypical telomeropathy showing with immune-dysregulation. This case underlines the importance of an accurate diagnostic work-up of patients with immune-dysregulation, who should undergo NGS or whole exome sequencing to identify specific disorders that deserve targeted follow-up and treatment. 相似文献
5.
Teodolinda Di Risi Mariella Cuomo Roberta Vinciguerra Sara Ferraro Rosa Della Monica Davide Costabile Michela Buonaiuto Federica Trio Ettore Capoluongo Roberta Visconti Eleonora Riccio Antonio Pisani Lorenzo Chiariotti 《International journal of molecular sciences》2022,23(20)
Anderson–Fabry disease (FD) is an X-linked disease caused by a functional deficit of the α-galactosidase A enzyme. FD diagnosis relies on the clinical manifestations and research of GLA gene mutations. However, because of the lack of a clear genotype/phenotype correlation, FD diagnosis can be challenging. Recently, several studies have highlighted the importance of investigating DNA methylation patterns for confirming the correct diagnosis of different rare Mendelian diseases, but to date, no such studies have been reported for FD. Thus, in the present investigation, we analyzed for the first time the genome-wide methylation profile of a well-characterized cohort of patients with Fabry disease. We profiled the methylation status of about 850,000 CpG sites in 5 FD patients, all carrying the same mutation in the GLA gene (exon 6 c.901C>G) and presenting comparable low levels of α-Gal A activity. We found that, although the whole methylome profile did not discriminate the FD group from the unaffected one, several genes were significantly differentially methylated in Fabry patients. Thus, we provide here a proof of concept, to be tested in patients with different mutations and in a larger cohort, that the methylation state of specific genes can potentially identify Fabry patients and possibly predict organ involvement and disease evolution. 相似文献
6.
The problem of automatically selecting the pose of a 3D object that corresponds to the most informative and intuitive view of the shape is known as the best view problem. In this paper we address the selection of the best view driven by the meaningful features of the shape, in order to maximize the visibility of salient components from the context or from the application point of view. Meaningful features can be automatically detected by means of semantic-oriented segmentations: we tested several approaches with very pleasant results in the automatic generation of thumbnails for large 3D model databases. 相似文献
7.
Barbara Peruzzi Enrica Urciuoli Michela Mariani Laura Chioma Luigi Tomao Ilaria Montano Mattia Algeri Rosa Luciano Danilo Fintini Melania Manco 《International journal of molecular sciences》2023,24(1)
Excess body weight has been considered beneficial to bone health because of its anabolic effect on bone formation; however, this results in a poor quality bone structure. In this context, we evaluated the involvement of circulating extracellular vesicles in the impairment of the bone phenotype associated with obesity. Circulating extracellular vesicles were collected from the plasma of participants with normal weight, as well as overweight and obese participants, quantified by flow cytometry analysis and used to treat mesenchymal stromal cells and osteoblasts to assess their effect on cell differentiation and activity. Children with obesity had the highest amount of circulating extracellular vesicles compared to controls. The treatment of mesenchymal stromal cells with extracellular vesicles from obese participants led to an adipogenic differentiation in comparison to vesicles from controls. Mature osteoblasts treated with extracellular vesicles from obese participants showed a reduction in differentiation markers in comparison to controls. Children with obesity who regularly performed physical exercise had a lower circulating extracellular vesicle amount in comparison to those with a sedentary lifestyle. This pilot study demonstrates how the high amount of circulating extracellular vesicles in children with obesity affects the bone phenotype and that physical activity can partially rescue this phenotype. 相似文献
8.
Giulia Gizzi Samuela Cataldi Claudia Mazzeschi Elisa Delvecchio Maria Rachele Ceccarini Michela Codini Elisabetta Albi 《International journal of molecular sciences》2022,23(13)
The relationship between cholesterol and cancer has been widely demonstrated. Clinical studies have shown changes in blood cholesterol levels in cancer patients. In parallel, basic research studies have shown that cholesterol is involved in the mechanisms of onset and progression of the disease. On the other hand, anorexic patients have high cholesterol levels and a high susceptibility to cancer. In this review, we first present a brief background on the relations among nutrition, eating disorders and cancer. Using several notable examples, we then illustrate the changes in cholesterol in cancer and in anorexia nervosa, providing evidence for their important relationship. Finally, we show a new possible link between cholesterol disorder in cancer and in anorexia nervosa. 相似文献
9.
Samantha Baldassarri Daniela Benati Federica DAlessio Clarissa Patrizi Eleonora Cattin Michela Gentile Angelo Raggioli Alessandra Recchia 《International journal of molecular sciences》2022,23(14)
Sleeping Beauty (SB) is the first DNA transposon employed for efficient transposition in vertebrate cells, opening new applications for genetic engineering and gene therapies. A transposon-based gene delivery system holds the favourable features of non-viral vectors and an attractive safety profile. Here, we employed SB to engineer HEK293 cells for optimizing the production of a chimpanzee Adenovector (chAd) belonging to the Human Mastadenovirus C species. To date, chAd vectors are employed in several clinical settings for infectious diseases, last but not least COVID-19. A robust, efficient and quick viral vector production could advance the clinical application of chAd vectors. To this aim, we firstly swapped the hAd5 E1 with chAd-C E1 gene by using the CRISPR/Cas9 system. We demonstrated that in the absence of human Ad5 E1, chimp Ad-C E1 gene did not support HEK293 survival. To improve chAd-C vector production, we engineered HEK293 cells to stably express the chAd-C precursor terminal protein (ch.pTP), which plays a crucial role in chimpanzee Adenoviral DNA replication. The results indicate that exogenous ch.pTP expression significantly ameliorate the packaging and amplification of recombinant chAd-C vectors thus, the engineered HEK293ch.pTP cells could represent a superior packaging cell line for the production of these vectors. 相似文献
10.
Michela Pecoraro Stefania Marzocco Silvia Franceschelli Ada Popolo 《International journal of molecular sciences》2022,23(12)
Human epidermal growth factor receptor-2 (HER2) is overexpressed in up to 30% of breast cancer cases, causing a more aggressive tumour growth and poor prognosis. Trastuzumab, the humanized antibody targeted to HER2, increased the life expectancy of patients, but severe cardiotoxicity emerged as a long-term adverse effect. Clinical evidence highlights that Trastuzumab-induced cardiotoxicity drastically increases in association with Doxorubicin; however, the exact mechanisms involved remain incompletely understood. In order to analyse the molecular mechanisms involved and the possible adaptative responses to Trastuzumab and Doxorubicin treatment, in this study, H9c2 cardiomyoblasts were used. Results showed that Trastuzumab and Doxorubicin sequential administration in cardiomyoblast increased cytosolic and mitochondrial ROS production, intracellular calcium dysregulation, mitochondrial membrane depolarization, and the consequent apoptosis, induced by both Trastuzumab and Doxorubicin alone. Furthermore, in these conditions, we observed increased levels of Connexin43 phosphorylated on Ser368 (pCx43). Since phosphorylation on Ser368 decreases gap junction intracellular communication, thus reducing the spread of death signals to adjacent cells, we hypothesized that the increase in pCx43 could be an adaptative response implemented by cells to defend neighbouring cells by Trastuzumab and Doxorubicin sequential administration. However, the other side of the coin is the resulting conduction abnormalities. 相似文献