2,419 research outputs found
Sensory semantic user interfaces (SenSUI)
Rapid evolution of the World Wide Web with its underlying sources of data, knowledge, services and applications continually attempts to support a variety of users, with different backgrounds, requirements and capabilities. In such an environment, it is highly unlikely that a single user interface will prevail and be able to fulfill the requirements of each user adequately. Adaptive user interfaces are able to adapt information and application functionalities to the user context. In contrast, pervasive computing and sensor networks open new opportunities for context aware platforms, one that is able to improve user interface adaptation reacting to environmental and user sensors. Semantic web technologies and ontologies are able to capture sensor data and provide contextual information about the user, their actions, required applications and environment. This paper investigates the viability of an approach where semantic web technologies are used to maximize the efficacy of interface adaptation through the use of available ontology
Portal vein embolization versus dual vein embolization for management of the future liver remnant in patients undergoing major hepatectomy: meta-analysis
BACKGROUND: This meta-analysis aimed to compare progression to surgery, extent of liver hypertrophy, and postoperative outcomes in patients planned for major hepatectomy following either portal vein embolization (PVE) or dual vein embolization (DVE) for management of an inadequate future liver remnant (FLR). METHODS: An electronic search was performed of MEDLINE, Embase, and PubMed databases using both medical subject headings (MeSH) and truncated word searches. Articles comparing PVE with DVE up to January 2022 were included. Articles comparing sequential DVE were excluded. ORs, risk ratios, and mean difference (MD) were calculated using fixed and random-effects models for meta-analysis. RESULTS: Eight retrospective studies including 523 patients were included in the study. Baseline characteristics between the groups, specifically, age, sex, BMI, indication for resection, and baseline FLR (ml and per cent) were comparable. The percentage increase in hypertrophy was larger in the DVE group, 66 per cent in the DVE group versus 27 per cent in the PVE group, MD 39.07 (9.09, 69.05) (P = 0.010). Significantly fewer patients failed to progress to surgery in the DVE group than the PVE group, 13 per cent versus 25 per cent respectively OR 0.53 (0.31, 0.90) (P = 0.020). Rates of post-hepatectomy liver failure 13 per cent versus 22 per cent (P = 0.130) and major complications 20 per cent versus 28 per cent (Clavien–Dindo more than IIIa) (P = 0.280) were lower. Perioperative mortality was lower with DVE, 1 per cent versus 10 per cent (P = 0.010). CONCLUSION: DVE seems to produce a greater degree of hypertrophy of the FLR than PVE alone which translates into more patients progressing to surgery. Higher quality studies are needed to confirm these results
Behavioural syndrome in a solitary predator is independent of body size and growth rate.
Models explaining behavioural syndromes often focus on state-dependency, linking behavioural variation to individual differences in other phenotypic features. Empirical studies are, however, rare. Here, we tested for a size and growth-dependent stable behavioural syndrome in the juvenile-stages of a solitary apex predator (pike, Esox lucius), shown as repeatable foraging behaviour across risk. Pike swimming activity, latency to prey attack, number of successful and unsuccessful prey attacks was measured during the presence/absence of visual contact with a competitor or predator. Foraging behaviour across risks was considered an appropriate indicator of boldness in this solitary predator where a trade-off between foraging behaviour and threat avoidance has been reported. Support was found for a behavioural syndrome, where the rank order differences in the foraging behaviour between individuals were maintained across time and risk situation. However, individual behaviour was independent of body size and growth in conditions of high food availability, showing no evidence to support the state-dependent personality hypothesis. The importance of a combination of spatial and temporal environmental variation for generating growth differences is highlighted
Adaptive Lévy processes and area-restricted search in human foraging
A considerable amount of research has claimed that animals’ foraging behaviors display movement lengths with power-law distributed tails, characteristic of Lévy flights and Lévy walks. Though these claims have recently come into question, the proposal that many animals forage using Lévy processes nonetheless remains. A Lévy process does not consider when or where resources are encountered, and samples movement lengths independently of past experience. However, Lévy processes too have come into question based on the observation that in patchy resource environments resource-sensitive foraging strategies, like area-restricted search, perform better than Lévy flights yet can still generate heavy-tailed distributions of movement lengths. To investigate these questions further, we tracked humans as they searched for hidden resources in an open-field virtual environment, with either patchy or dispersed resource distributions. Supporting previous research, for both conditions logarithmic binning methods were consistent with Lévy flights and rank-frequency methods–comparing alternative distributions using maximum likelihood methods–showed the strongest support for bounded power-law distributions (truncated Lévy flights). However, goodness-of-fit tests found that even bounded power-law distributions only accurately characterized movement behavior for 4 (out of 32) participants. Moreover, paths in the patchy environment (but not the dispersed environment) showed a transition to intensive search following resource encounters, characteristic of area-restricted search. Transferring paths between environments revealed that paths generated in the patchy environment were adapted to that environment. Our results suggest that though power-law distributions do not accurately reflect human search, Lévy processes may still describe movement in dispersed environments, but not in patchy environments–where search was area-restricted. Furthermore, our results indicate that search strategies cannot be inferred without knowing how organisms respond to resources–as both patched and dispersed conditions led to similar Lévy-like movement distributions
Reflections on the labyrinth: Investigating Black and Minority Ethnic leaders’ career experiences
Black and Minority Ethnic (BME) employees appear to experience more difficulty reaching senior leadership positions than their white counterparts. Using Eagly and Carli’s (2007) metaphor of the labyrinth our aim was to give voice to black and minority ethnic managers who have successfully achieved senior management roles, and compare their leadership journeys with those of matched white managers. This paper used semi-structured interviews and attribution theory to examine how 20 black and minority ethnic and 20 white senior managers, from a UK government department made sense of significant career incidents in their leadership journeys. Template analysis was used to identify facilitators and barriers of career progression from causal explanations of these incidents. Although BME and white managers identified four common themes (visibility, networks, development, and line manager support), they differed in how they made sense of formal and informal organisational processes to achieve career progression. The findings are used to theorise about the individual and organisational factors that contribute to the leadership journeys of minority ethnic employees
Non-canonical Keap1-independent activation of Nrf2 in astrocytes by mild oxidative stress
The transcription factor Nrf2 is a stress-responsive master regulator of antioxidant, detoxification and proteostasis genes. In astrocytes, Nrf2-dependent gene expression drives cell-autonomous cytoprotection and also non-cell-autonomous protection of nearby neurons, and can ameliorate pathology in several acute and chronic neurological disorders associated with oxidative stress. However, the value of astrocytic Nrf2 as a therapeutic target depends in part on whether Nrf2 activation by disease-associated oxidative stress occludes the effect of any Nrf2-activating drug. Nrf2 activation classically involves the inhibition of interactions between Nrf2's Neh2 domain and Keap1, which directs Nrf2 degradation. Keap1 inhibition is mediated by the modification of cysteine residues on Keap1, and can be triggered by electrophilic small molecules such as tBHQ. Here we show that astrocytic Nrf2 activation by oxidative stress involves Keap1-independent non-canonical signaling. Keap1 deficiency elevates basal Nrf2 target gene expression in astrocytes and occludes the effects of tBHQ, oxidative stress still induced strong Nrf2-dependent gene expression in Keap1-deficient astrocytes. Moreover, while tBHQ prevented protein degradation mediated via Nrf2's Neh2 domain, oxidative stress did not, consistent with a Keap1-independent mechanism. Moreover the effects of oxidative stress and tBHQ on Nrf2 target gene expression are additive, not occlusive. Mechanistically, oxidative stress enhances the transactivation potential of Nrf2's Neh5 domain in a manner dependent on its Cys-191 residue. Thus, astrocytic Nrf2 activation by oxidative stress involves Keap1-independent non-canonical signaling, meaning that further Nrf2 activation by Keap1-inhibiting drugs may be a viable therapeutic strategy
Differences in smoking associated DNA methylation patterns in South Asians and Europeans
This is a freely-available open access publication. Please cite the published version which is available via the DOI link in this record.Background
DNA methylation is strongly associated with smoking status at multiple sites across the genome. Studies have largely been restricted to European origin individuals yet the greatest increase in smoking is occurring in low income countries, such as the Indian subcontinent. We determined whether there are differences between South Asians and Europeans in smoking related loci, and if a smoking score, combining all smoking related DNA methylation scores, could differentiate smokers from non-smokers.
Results
Illumina HM450k BeadChip arrays were performed on 192 samples from the Southall And Brent REvisited (SABRE) cohort. Differential methylation in smokers was identified in 29 individual CpG sites at 18 unique loci. Interaction between smoking status and ethnic group was identified at the AHRR locus. Ethnic differences in DNA methylation were identified in non-smokers at two further loci, 6p21.33 and GNG12. With the exception of GFI1 and MYO1G these differences were largely unaffected by adjustment for cell composition. A smoking score based on methylation profile was constructed. Current smokers were identified with 100% sensitivity and 97% specificity in Europeans and with 80% sensitivity and 95% specificity in South Asians.
Conclusions
Differences in ethnic groups were identified in both single CpG sites and combined smoking score. The smoking score is a valuable tool for identification of true current smoking behaviour. Explanations for ethnic differences in DNA methylation in association with smoking may provide valuable clues to disease pathways.Wellcome Trust Enhancement grantMedical Research CouncilDiabetes UKthe British Heart Foundatio
In Vivo Evaluation of the Presence of Bone Marrow in Cortical Porosity in Postmenopausal Osteopenic Women
This is the first observational study examining cortical porosity in vivo in postmenopausal osteopenic women and to incorporate data from two different imaging modalities to further examine the nature of cortical porosity. The goal of this study was to combine high-resolution peripheral computed tomography (HR-pQCT) images, which contain high spatial resolution information of the cortical structure, and magnetic resonance (MR) images, which allow the visualization of soft tissues such as bone marrow, to observe the amount of cortical porosity that contains bone marrow in postmenopausal osteopenic women. The radius of 49 and the tibia of 51 postmenopausal osteopenic women (age 56 ± 3.7) were scanned using both HR-pQCT and MR imaging. A normalized mutual information registration algorithm was used to obtain a three-dimensional rigid transform which aligned the MR image to the HR-pQCT image. The aligned images allowed for the visualization of bone marrow in cortical pores. From the HR-pQCT image, the percent cortical porosity, the number of cortical pores, and the size of each cortical pore was determined. By overlaying the aligned MR and HR-pQCT images, the percent of cortical pores containing marrow, the number of cortical pores containing marrow, and the size of each cortical pore containing marrow were measured. While the amount of cortical porosity did not vary greatly between subjects, the type of cortical pore, containing marrow vs. not containing marrow, varied highly between subjects. The results suggest that cortical pore spaces contain components of varying composition, and that there may be more than one mechanism for the development of cortical porosity
A bibliometric study of the literature on technological innovation: an analysis of 60 international academic journals
This paper aims to contribute to the debate on technological innovation, organization and work. Although technological innovation remained a debated topic in the academic literature during the past years, its implications for organizational processes seem still not sufficiently theorized and empirically investigated. By using two complementary journals’ rankings a search in the ISI Web of Science platform from 1985 through 2013 was performed. To analyze the 998 scientific retrieved contributions a bibliometric analysis has been conducted, adopting also Social Network Analysis tools. Our results reveal a significant growth of the technological innovation literature over the investigated period, the multidisciplinarity of the field and, particularly, the relevance of management and business & economics contributions. Overall, this study offers a broad overview of the literature on technological innovation and emphasizes the opportunity to investigate the role of technological innovation within the organizational life.This paper aims to contribute to the debate on technological innovation, organization and work. Although technological innovation remained a debated topic in the academic literature during the past years, its implications for organizational processes seem still not sufficiently theorized and empirically investigated. By using two complementary journals’ rankings a search in the ISI Web of Science platform from 1985 through 2013 was performed. To analyze the 998 scientific retrieved contributions a bibliometric analysis has been conducted, adopting also Social Network Analysis tools. Our results reveal a significant growth of the technological innovation literature over the investigated period, the multidisciplinarity of the field and, particularly, the relevance of management and business & economics contributions. Overall, this study offers a broad overview of the literature on technological innovation and emphasizes the opportunity to investigate the role of technological innovation within the organizational life.Monograph's chapter
- …