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排序方式: 共有453条查询结果,搜索用时 15 毫秒
91.
Ralf De Wolf Ellen Vanderhoven Bettina Berendt Jo Pierson Tammy Schellens 《Behaviour & Information Technology》2017,36(5):459-469
The increasing popularity of social networking sites has been a source of many privacy concerns. To mitigate these concerns and empower users, different forms of educational and technological solutions have been developed. Developing and evaluating such solutions, however, cannot be considered a neutral process. Instead, it is socially bound and interwoven with norms and values of the researchers. In this contribution, we aim to make the research process and development of privacy solutions more transparent by highlighting questions that should be considered. (1) Which actors are involved in formulating the privacy problem? (2) Is privacy perceived as a human right or as a property right on one’s data? (3) Is informing users of privacy dangers always a good thing? (4) Do we want to influence users’ attitudes and behaviours? (5) Who is the target audience? We argue that these questions can help researchers to better comprehend their own perspective on privacy, that of others, and the influence of the solutions they are developing. In the discussion, we propose a procedure called ‘tool clinics’ for further practical implementations. 相似文献
92.
Exploiting Noncovalent Interactions in an Imine‐Based Covalent Organic Framework for Quercetin Delivery
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93.
Paul Braunger Christian Korunka Bettina Kubicek Hermann Frank Manfred Lueger 《人机工程学与制造业中的人性因素》2015,25(2):198-210
The aim of this study was to investigate safety climate and how it relates to the safety performance of employees from the perspective of safety engineers. Using Griffin and Neal's (2000) safety climate model as a theoretical basis, we hypothesized that the organizational safety climate is a higher‐order construct that relates to the safety compliance of employees and their safety participation via the mediating roles of safety knowledge and safety motivation. Hypotheses were tested among 236 safety engineers working in the wood and metal‐processing industries in Austria. Structural equation modeling (SEM) analysis showed that safety climate is a higher‐order construct comprising manager values, safety communication, safety practices, safety training, and safety equipment. Moreover, from the perspective of safety engineers, the safety climate of the organizations was related to employee safety motivation, which in turn related to their safety compliance and safety participation. In contrast to our assumptions, the safety knowledge of employees was, in the view of safety engineers, neither related to employee safety compliance nor to their safety participation. Multigroup analysis revealed no differences between internally and externally employed safety engineers for these relations. Thus, although the safety climate model was generally confirmed from an engineer's perspective, engineers rated motivational aspects of safety climate is more important compared to knowledge aspects. 相似文献
94.
We investigated the effect of an elevated ambient temperature on performance in a persistence task. The task involved the coding of incorrect symbols and participants were free to decide how long to spend performing this task. Applying a between-subject design, we tested 125 students in an office-like environment in one of the three temperature conditions. The comfort condition (Predicted Mean Vote [PMV] = 0.01) featured an average air temperature of 24 °C. The elevated ambient temperature condition was 28 °C (PMV = 1.17). Condition three employed an airstream of approximately 0.8 m/s, intended to compensate for performance decrements at the elevated air temperature (28 °C, PMV = 0.13), according to Fanger’s thermal comfort equation. Participants in the warm condition were significantly less persistent compared with participants in the control and compensation conditions. As predicted by the thermal comfort equation, the airstream seemed to compensate for the higher temperature. Participants’ persistence in the compensation and comfort conditions did not differ.
Practitioner Summary: A laboratory experiment involving a simulated office environment and three ambient temperature conditions (24 °C, 28 °C and 28 °C plus airstream) showed that persistence at a task is significantly impaired at 28 °C. An airstream of 0.8 m/s at 28 °C compensated for the disinclination to persist with the task. 相似文献
95.
CO oxidation over structured carriers: A comparison of ceramic foams, honeycombs and beads 总被引:1,自引:0,他引:1
Florina Corina Patcas Gerardo Incera Garrido Bettina Kraushaar-Czarnetzki 《Chemical engineering science》2007,62(15):3984-3990
This work aims an experimental comparison of different packings on the basis of their pressure drop, mass and heat transfer properties. Ceramic foams, beads and a honeycomb monolith were used as carriers in the oxidation of carbon monoxide. The carriers were coated with active Pt/SnO2. The CO oxidation rate was measured in the regime of external diffusion control at superficial gas velocities between 1 and 10 m/s. The volumetric rate coefficients and the pressure drop of packings with similar geometric surface area decreased in the sequence particles > foams > honeycomb. The magnitude of the temperature gradient along the catalytic bed decreased as going from honeycomb over larger particles to foams and small particles. Foams were superior over particle beds from the viewpoint of combined high mass transfer and low-pressure drop. The main advantage of foams as compared to honeycomb resided in the radial mixing enabling a better heat transfer to the reactor walls. 相似文献
96.
Kamal Zellag Bettina Kemme 《The VLDB Journal The International Journal on Very Large Data Bases》2014,23(1):147-172
Modern transaction systems, consisting of an application server tier and a database tier, offer several levels of isolation providing a trade-off between performance and consistency. While it is fairly well known how to identify qualitatively the anomalies that are possible under a certain isolation level, it is much more difficult to detect and quantify such anomalies during run-time of a given application. In this paper, we present a new approach to detect and quantify consistency anomalies for arbitrary multi-tier application running under any isolation levels ensuring at least read committed. In fact, the application can run even under a mixture of isolation levels. Our detection approach can be online or off-line and for each detected anomaly, we identify exactly the transactions and data items involved. Furthermore, we classify the detected anomalies into patterns showing the business methods involved as well as analyzing the types of cycles that occur. Our approach can help designers to either choose an isolation level where the anomalies do not occur or to change the transaction design to avoid the anomalies. Furthermore, we provide an option in which the occurrence of anomalies can be automatically reduced during run-time. To test the effectiveness and efficiency of our approach, we have conducted a set of experiments using a wide range of benchmarks. 相似文献
97.
A competing risks model based on Lomax distributions is considered under progressive Type-II censoring. Maximum likelihood estimates for the distribution parameters are established. Moreover, the expected Fisher information matrix is computed and optimal Fisher information based censoring plans are discussed. In particular, it turns out that the optimal censoring scheme depends on the particular parametrization of the Lomax distributions. 相似文献
98.
Luis M. Montao Bettina Sommer Hctor Solís-Chagoyn Bianca S. Romero-Martínez Arnoldo Aquino-Glvez Juan C. Gomez-Verjan Eduardo Calixto Georgina Gonzlez-Avila Edgar Flores-Soto 《International journal of molecular sciences》2022,23(2)
The health scourge imposed on humanity by the COVID-19 pandemic seems not to recede. This fact warrants refined and novel ideas analyzing different aspects of the illness. One such aspect is related to the observation that most COVID-19 casualties were older males, a tendency also noticed in the epidemics of SARS-CoV in 2003 and the Middle East respiratory syndrome in 2012. This gender-related difference in the COVID-19 death toll might be directly involved with testosterone (TEST) and its plasmatic concentration in men. TEST has been demonstrated to provide men with anti-inflammatory and immunological advantages. As the plasmatic concentration of this androgen decreases with age, the health benefit it confers also diminishes. Low plasmatic levels of TEST can be determinant in the infection’s outcome and might be related to a dysfunctional cell Ca2+ homeostasis. Not only does TEST modulate the activity of diverse proteins that regulate cellular calcium concentrations, but these proteins have also been proven to be necessary for the replication of many viruses. Therefore, we discuss herein how TEST regulates different Ca2+-handling proteins in healthy tissues and propose how low TEST concentrations might facilitate the replication of the SARS-CoV-2 virus through the lack of modulation of the mechanisms that regulate intracellular Ca2+ concentrations. 相似文献
99.
Matas Jakubauskas Lina Jakubauskiene Bettina Leber Angela Horvath Kestutis Strupas Philipp Stiegler Peter Schemmer 《International journal of molecular sciences》2022,23(14)
Colorectal cancer (CRC) ranks third in incidence and second in mortality of all cancers worldwide. At the time of primary diagnosis, around 20% of patients already have metastatic CRC and only around 20% are candidates for radical resection. Thus, most of the patients have to undergo chemotherapy (CTx). Due to chemoresistance and side effects, novel treatment additives are crucial for controlling the disease and prolonging patient survival. The aim of this study was to evaluate probiotic supplementation and its antitumorigenic effects in an experimental CRC liver metastasis model. Six-week-old male Wistar rats received either a multispecies probiotic (1.2 × 109 CFU/daily) or placebo mixture. On day 14 of the experiment, rat CRC cells (CC531) were implanted under the liver capsule later treated by FOLFOX CTx. Change in tumor volume was measured by performing micro computed tomography (micro-CT) scanning on experimental days 28 and 34. Additionally, immunohistochemical staining with anti-MPO, anti-Ki67, and anti-CD31 were performed. Tumor apoptosis was evaluated using TUNEL staining. Micro-CT image analysis indicates that probiotic supplementation significantly inhibits tumor growth. No synergistic effects between probiotic supplementation and FOLFOX CTx was observed. Reduced tumor volume was achieved by inhibiting angiogenesis, as tumor microvascular density was significantly lower in rats receiving probiotic supplementation. This study shows that a multispecies probiotic mixture significantly reduces angiogenesis and inhibits CRC liver metastasis growth in an experimental rat model. 相似文献
100.
Lina Jakubauskiene Matas Jakubauskas Gintare Razanskiene Bettina Leber Jennifer Weber Lisa Rohrhofer Diana Ramasauskaite Kestutis Strupas Philipp Stiegler Peter Schemmer 《International journal of molecular sciences》2022,23(13)
Successful uterus transplantation, a potential treatment method for women suffering from absolute uterine infertility, is negatively affected by ischemia–reperfusion injury (IRI). The aim of this study is to investigate the protective effect of relaxin (RLX) or/and erythropoietin (EPO) on experimental uterus IRI. Eighty rats, randomly assigned into eight groups (n = 10/group), were pretreated with either saline, 5 μg/kg human relaxin-2, 4000 IU/kg recombinant human erythropoietin or their combination. Ischemia was achieved by clamping the aorta and ovarian arteries for 60 min, following 120 min of reperfusion and tissue sampling. For sham animals, clamping was omitted during surgery. There were no differences in tissue histological score, malondialdehyde (MDA) and superoxide dismutase (SOD) levels, myeloperoxidase (MPO) and TUNEL-positive cell count between all sham-operated rats. Pretreatment with RLX preserved normal tissue morphology, reduced MDA levels, MPO and TUNEL-positive cell count, preserved SOD activity and upregulated NICD and HES1 gene expression when compared to the control group. Pretreatment with EPO reduced MDA levels. In conclusion, pretreatment with RLX, EPO or a combination of both EPO and RLX significantly alleviates uterine tissue damage caused by IRI. 相似文献