4,469 research outputs found
Trends and preferences of Internet participants: differences between SNS users and non-users
The staggering growth of online social networking and the potential of Social Networking Sites as marketing channels has become an issue of attention and interest by commercial organizations. This explorative study provides the basis for understanding the nature and behaviour of users of these sites. Based on a national sample, this paper investigates the demographics, profiles and behaviour of participants of Social Networking Sites in The Netherlands. The paper compares the online behaviour of users and non-users of SNS and reveals that the first category of networked citizens is much more active on most types of online activities. Furthermore the study identifies the profile of the average participant in online social networks, identifies preferences and reveals ways that online citizens are engaged with this particular form of social media. The findings provide a better understanding of the importance of the Social Networks for the digital citizen and present useful facts to marketers eager to integrate these media into their marketing approaches and strategies; they also present researchers of human behaviour with interesting insights on the role of the online social networks as platforms of social interaction and communication
Segmentation of users of social networking websites
The typology of networked consumers in The Netherlands presented in this study, was based on an online survey and obtained using latent segmentation analysis. This approach is based on the frequency with which users perform different activities, their sociodemographic variables, social networking experience, and patterns of interaction. The findings present new insights for marketing strategists wishing to use the communication potential of online social networks and for marketers willing to explore the potential of online networking as a low-cost, efficient alternative to traditional networking approaches. The findings also present researchers of social behavior with interesting insights into the role of online social networks as a platform for social interaction and communicatio
Segmenting the social networking sites users: An empirical study
The growth of social networking sites (SNS) presents businesses and marketers with risks and challenges. Customers become sophisticated, empowered and increasingly involved in shaping of the marketing offer. Marketers are becoming aware of the threat of losing control over their message but also begin to realise the potential of SNS as marketing tools; understanding the nature of the SNS users and the way they interact online is a vital step in developing business strategies targeting and engaging the networked consumer. The paper presents an explorative survey on the demographics, background, adoption motives and behaviour of SNS users as bases for the identification of segments in this market. The survey, held among SNS users in The Netherlands, identifies four distinctive user profiles of social networking users. The paper presents the results of the survey, discusses the management implications of the findings and identifies areas of future research
Identification of β2 microglobulin, the product of B2M gene, as a Host Factor for Vaccinia Virus Infection by Genome-Wide CRISPR genetic screens
Genome-wide genetic screens are powerful tools to identify genes that act as host factors of viruses. We have applied this technique to analyze the infection of HeLa cells by Vaccinia virus, in an attempt to find genes necessary for infection. Infection of cell populations harboring single gene inactivations resulted in no surviving cells, suggesting that no single gene knock-out was able to provide complete resistance to Vaccinia virus and thus allow cells to survive infection. In the absence of an absolute infection blockage, we explored if some gene inactivations could provide partial protection leading to a reduced probability of infection. Multiple experiments using modified screening procedures involving replication restricted viruses led to the identification of multiple genes whose inactivation potentially increase resistance to infection and therefore cell survival. As expected, significant gene hits were related to proteins known to act in virus entry, such as ITGB1 and AXL as well as genes belonging to their downstream related pathways. Additionally, we consistently found β2-microglobulin, encoded by the B2M gene, among the screening top hits, a novel finding that was further explored. Inactivation of B2M resulted in 54% and 91% reduced VV infection efficiency in HeLa and HAP1 cell lines respectively. In the absence of B2M, while virus binding to the cells was unaffected, virus internalization and early gene expression were significantly diminished. These results point to β2-microglobulin as a relevant factor in the Vaccinia virus entry process.This work was supported by grants ERTA2014-00006, RTA2017-0066 and PID2021-128466OR-I00 funded by Ministerio de Ciencia e Innovación MCIN/AEI/10.13039/501100011033 as part of the Plan Estatal de Investigación Científica, Desarrollo e Innovación (https://www.ciencia.gob.es) to R.B. A.M. was recipient of a predoctoral contract from Subprograma Estatal de Formación, Programa Estatal de Promoción del Talento y su Empleabilidad en I+D+I, Spain from the Ministerio de Ciencia e Innovación, grant number PRE2018-085415. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.S
An ontology for integrated machining and inspection process planning focusing on resource capabilities
The search for and assignment of resources is extremely important for the efficient planning of any process in a distributed environment, such as the collaborative product integrated development process. These environments require a degree of semantic interoperability, which currently can only be provided by ontological models. However, the ontological proposals centred on Resources for Machining and nspection Process Planning have a limited reach, do not adopt a unified view of machining and inspection, and fail to express knowledge in the manner required by some of the planning tasks, as is the case with those concerned with resource assignment and plan validation. With the aim of providing a solution to these shortcomings the manufacturing and inspection resource capability (MIRC) ontology has been developed, as a specialist offshoot of the product and processes development resources capability ontology. This ontology considers resource capabilities to be a characteristic of the resource executing any activity present in an integrated process plan. Special attention is given to resource preparation activities, due to their influence on the quality of the final product. After describing the MIRC ontology, a case study demonstrates how the ontology supports the process planning for any level, approach or plan strategy.This work has been possible thanks to the funding received from the Spanish Ministry of Science and Education through the COAPP Research Project [reference DPI2007-66871-C02-01/02].Solano García, L.; Romero Subirón, F.; Rosado Castellano, P. (2016). An ontology for integrated machining and inspection process planning focusing on resource capabilities. International Journal of Computer Integrated Manufacturing. 29(1):1-15. doi:10.1080/0951192X.2014.1003149S11529
A comparison among PCNL, Miniperc and Ultraminiperc for lower calyceal stones between 1 and 2 cm: A prospective, comparative, multicenter and randomised study
Background: Conventional Percutaneous Lithotripsy (PCNL) has been an effective, successful and easy approach for especially > 1 cm sized calyceal stones however risks of complications and nephron loss are inevitable. Our aim is to compare the efficacy and safety of PCNL, MiniPerc (MP) and UltraMiniPerc (UMP) for lower calyceal stones between 1 and 2 cm with a multicenter prospective randomized study. Methods: Between January 2015 and June 2018, 132 consecutive patients with single lower calyceal stone were enrolled. Patients were randomized in three groups; A: PCNL; B: MP; C: UMP. 44 patients for the Group A, 47 for Group B and 41 for Group C. Exclusion criterias were the presence of coagulation impairments, age of < 18 or > 75, presence of infection or serious comorbidities. Patients were controlled with computerized tomography scan after 3 months. A negative CT or an asymptomatic patient with stone fragments < 3 mm size were the criteria to assess the stone-free status. Patient characteristics, stone free rates (SFR) s, complications and re-treatment rates were analyzed. Results: The mean stone size were 16.38, 16.82 and 15.23 mm respectively in Group A, B and C(p = 0.34). The overall SFR was significantly higher in Group A (86.3%) and B (82.9%) as compared to Group C (78%)(p < 0.05). The re-treatment rate was significantly higher in Group C (12.1%) and complication rates was higher in Group A (13.6%) as compared to others(p < 0.05). The hospitalization was significantly shorter in Group C compared to Group A (p = 0.04). Conclusions: PCNL and MP showed higher efficacy than UMP to obtain a better SFR. Auxiliary and re-treatment rates were higher in UMP. On the other hand for such this kind of stones PCNL had more complications. Overall evaluation favors MP as a better indication in stones 1-2 cm size
Physical characterization of long-lasting hybrid eruptions: the 2021 tajogaite eruption of Cumbre Vieja (La Palma, Canary Islands)
Long-lasting, hybrid eruptions can be of complex description and classification, especially when associated with multiple eruptive styles and multiple products. The 2021 Tajogaite eruption of La Palma, Canary Islands, was associated with a magma-gas decoupled system that resulted in the simultaneous emission of lava flows and tephra plumes from various vents. Even though the tephra blanket (∼2 × 107 m3) represents only 7%–16% of the total erupted volume, it provides fundamental insights into the overall eruptive dynamics. Tephra was mostly dispersed NE-SW due to a complex regional and local wind patterns and was subdivided into 3 units and 11 layers that well correlate at different distances from the vent and with both tremor data and lava emission rate. While plume height varied at the temporal scale of a few hours, the average mass eruption rate associated with the tephra blanket of the different units remained relatively constant (∼3–4 × 103 kg s−1). In contrast, the emission rate of lava largely increased after the first week and remained higher than the overall emission of tephra throughout the whole eruption (average value of ∼6 × 104 kg s−1). Based on a detailed characterization of the tephra blanket in combination with atmospheric wind, tremor, and lava emission trend, we demonstrate the need of (a) multidisciplinary strategies for the description of hybrid eruptions that account for both the duration of individual phases and the quantification of the mass of multiple products, and of (b) dedicated ash dispersal forecasting strategies that account for the frequent variations of eruptive and atmospheric conditions.Research activities were supported by Swiss National Science Foundation (Grant 200020_188757) and by the projects (a) VOLRISKMAC (MAC/3.5b/124) and (b) VOLRISKMAC II (MAC2/3.5b/328), financed by the Program INTERREG VA Spain-Portugal MAC 2014–2020 of the European Commission; (c) Cumbre Vieja Emergencia, financed by the Science and Innovation Ministry, Spanish Government; and (d) Tfassistance, financed by the Cabildo Insular de Tenerife. JER fieldwork was partially financed through NSFGEONERC-DisEqm (NERC Reference: NE/N018575/1) and V-PLUS projects (Prof. Mike Burton).Peer reviewe
Precipitable water vapour content above the Roque de los Muchachos observatory from GPS estimations
ABSTRACT The requirements for current large and future extremely large telescopes as well as the quick development of IR instrumentation demand a proper characterization of precipitable water vapour (PWV) above astronomical sites. A comparison of PWV estimations from a photometer and a GPS (Global Positioning System) above the Observatorio del Roque de los Muchachos (ORM, La Palma, Canary Islands, Spain) was carried out and it was found a linear relation between both measurements. Such relationship will allow the calibration of the GPS measurements recorded at ORM for the period June 2001-December 2008. These large time series of PWV estimations from GPS were used to perform a statistical analysis of water vapour content above this astronomical site. Average annual value of night-time PWV of 4.86 mm was found. It was also found a clear seasonal behavior of the PWV above ORM, with smaller water-vapour columns during winter nights (average 3.36 mm). The largest values of PWV are reached in the summer nights (average 6.75 mm). The data indicate that a significant percentage of nights (~38%) are well suited for thermal infrared observations (with PWV < 3 mm), and 71% of nights present a "fair" or better IR observation opportunity at ORM
Importancia del agua en la hidratación de la población española: documento FESNAD 2010
For any healthy individual, thirst is an appropriate sign to drink water, except for babies, sportsmen, and most of ill and elderly people. In these instances, it is convenient to schedule appropriate times to drink water since great demands and the physiological mechanisms that determine thirst in these situations may condition water unbalances with important consequences for health and the physical and intellectual performance. The human body has a number of mechanisms that allow keeping constant the water content by adjusting intakes and wastes. Water balance is determined by intake (consumed water, beverages, and water contained in foods) and wastes (urine, stools, the skin, and expired air from the lungs). Failure of these mechanisms and subsequent impairments in water balance may produce severe disarrangements that may threaten somebody's life. In the present document, we analyze the evidences regarding the factors conditioning water needs in the different life stages and physiological situations, as well as the consequences of water unbalance under different situations. A proper hydration may be achieved by feeding and the use of water and other liquids. Although water is the beverage by excellence and represents the ideal way of restoring the losses and get hydrated, we should be aware that, from the very beginning, we have sought other liquid sources with hydration properties. In the last decades we have increased the consumption of different beverages, with a proliferation of sugar-containing beverages. Since excessive sugar consumption has been related to obesity and other chronic conditions, it is evident that the use of these caloric beverages should be rationalized, especially in children. In this document all the considerations regarding hydration are presented and different recommendations are expose
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