220 research outputs found
3DFeat-Net: Weakly Supervised Local 3D Features for Point Cloud Registration
In this paper, we propose the 3DFeat-Net which learns both 3D feature
detector and descriptor for point cloud matching using weak supervision. Unlike
many existing works, we do not require manual annotation of matching point
clusters. Instead, we leverage on alignment and attention mechanisms to learn
feature correspondences from GPS/INS tagged 3D point clouds without explicitly
specifying them. We create training and benchmark outdoor Lidar datasets, and
experiments show that 3DFeat-Net obtains state-of-the-art performance on these
gravity-aligned datasets.Comment: 17 pages, 6 figures. Accepted in ECCV 201
Boring bivalve traces in modern reef and deeper-water macroid and rhodolith beds
Macroids and rhodoliths, made by encrusting acervulinid foraminifera and coralline algae, are widely recognized as
bioengineers providing relatively stable microhabitats and increasing biodiversity for other species. Macroid and
rhodolith beds occur in different depositional settings at various localities and bathymetries worldwide. Six case
studies of macroid/rhodolith beds from 0 to 117m water depth in the Pacific Ocean (northern Central Ryukyu
Islands, French Polynesia), eastern Australia (Fraser Island, One Tree Reef, Lizard Island), and the Mediterranean Sea
(southeastern Spain) show that nodules in the beds are perforated by small-sized boring bivalve traces
(Gastrochanolites). On average, boring bivalve shells (gastrochaenids and mytilids) are more slender and smaller than
those living inside shallow-water rocky substrates. In the Pacific, Gastrochaena cuneiformis, Gastrochaena sp., Leiosolenus
malaccanus, L. mucronatus, L. spp., and Lithophaga/Leiosolenus sp., for the first time identified below 20m water depth,
occur as juvenile forms along with rare small-sized adults. In deep-water macroids and rhodoliths the boring bivalves
are larger than the shallower counterparts in which growth of juveniles is probably restrained by higher overturn rates
of host nodules. In general, most boring bivalves are juveniles that grew faster than the acervulinid foraminiferal and
coralline red algal hosts and rarely reached the adult stage. As a consequence of phenotypic plasticity, small-sized
adults with slow growth rates coexist with juveniles. Below wave base macroids and rhodoliths had the highest
amounts of bioerosion, mainly produced by sponges and polychaete worms. These modern observations provide
bases for paleobiological inferences in fossil occurrences.Ministry of Education, Culture, Sports, Science and Technology, Japan (MEXT)
Japan Society for the Promotion of Science
Grants-in-Aid for Scientific Research (KAKENHI)
25247083Erasmus+FAR2012-2017FIR2016FIR2018PRIN "Biotic resilience to global change: biomineralization of planktonic and benthic calcifiers in the past, present and future"
2017RX9XXXYBioMed Central-Prepay Membership at the University of FerraraJunta de Andalucía
RNM 190Committee on ResearchMuseum of PaleontologyDepartment of Integrative Biology, UC BerkeleyUC Pacific Rim Projec
Siamese Survival Analysis with Competing Risks
Survival analysis in the presence of multiple possible adverse events, i.e.,
competing risks, is a pervasive problem in many industries (healthcare,
finance, etc.). Since only one event is typically observed, the incidence of an
event of interest is often obscured by other related competing events. This
nonidentifiability, or inability to estimate true cause-specific survival
curves from empirical data, further complicates competing risk survival
analysis. We introduce Siamese Survival Prognosis Network (SSPN), a novel deep
learning architecture for estimating personalized risk scores in the presence
of competing risks. SSPN circumvents the nonidentifiability problem by avoiding
the estimation of cause-specific survival curves and instead determines
pairwise concordant time-dependent risks, where longer event times are assigned
lower risks. Furthermore, SSPN is able to directly optimize an approximation to
the C-discrimination index, rather than relying on well-known metrics which are
unable to capture the unique requirements of survival analysis with competing
risks
Are different groups of patients with stroke more likely to be excluded from the new UK general medical services contract? A cross-sectional retrospective analysis of a large primary care population
Peer reviewedPublisher PD
Universities’ pursuit of inclusion and its effects on professional staff: the case of the United Kingdom
This paper explores the proliferation of non-academic professionals as a cultural response to universities’ mission of inclusion. Departing from a neo-institutionalist perspective, the author argues that the diffusion of highly rationalised models of institutional action shapes universities as formal organisations who engage with new levels of professional expertise in the pursuit of goals and missions. The United Kingdom (UK) offers an illustrative example, the emergence of statutory equality duties on public institutions (race equality duty 2001, disability equality duty 2006 and gender equality duty 2007) nurturing an image of universities as strategic for the pursuit of demographic inclusion. Using yearly longitudinal data on 109 UK universities from 2003 to 2011, the author shows that universities increase their professional staff in catering for demographic inclusion in terms of ethnicity and disability, revealing highly rationalised institutional responses to the aforementioned equality duties. The findings contribute to the neo-institutionalist literature drawing attention to the transformation of universities into organisational actors (i.e. highly integrated entities, strategically oriented towards the pursuit of formally articulated goals and targets), which contrasts with traditional conceptions of the university as an institution with a taken-for-granted societal role and loosely defined organisational backbone. The findings provide the impetuous for further empirical research into the role of professional staff as universities assimilate new goals and missions
Listening In on the Past: What Can Otolith δ18O Values Really Tell Us about the Environmental History of Fishes?
Oxygen isotope ratios from fish otoliths are used to discriminate marine stocks and reconstruct past climate, assuming that variations in otolith δ18O values closely reflect differences in temperature history of fish when accounting for salinity induced variability in water δ18O. To investigate this, we exploited the environmental and migratory data gathered from a decade using archival tags to study the behaviour of adult plaice (Pleuronectes platessa L.) in the North Sea. Based on the tag-derived monthly distributions of the fish and corresponding temperature and salinity estimates modelled across three consecutive years, we first predicted annual otolith δ18O values for three geographically discrete offshore sub-stocks, using three alternative plausible scenarios for otolith growth. Comparison of predicted vs. measured annual δ18O values demonstrated >96% correct prediction of sub-stock membership, irrespective of the otolith growth scenario. Pronounced inter-stock differences in δ18O values, notably in summer, provide a robust marker for reconstructing broad-scale plaice distribution in the North Sea. However, although largely congruent, measured and predicted annual δ18O values of did not fully match. Small, but consistent, offsets were also observed between individual high-resolution otolith δ18O values measured during tag recording time and corresponding δ18O predictions using concomitant tag-recorded temperatures and location-specific salinity estimates. The nature of the shifts differed among sub-stocks, suggesting specific vital effects linked to variation in physiological response to temperature. Therefore, although otolith δ18O in free-ranging fish largely reflects environmental temperature and salinity, we counsel prudence when interpreting otolith δ18O data for stock discrimination or temperature reconstruction until the mechanisms underpinning otolith δ18O signature acquisition, and associated variation, are clarified
A statistical model for estimation of fish density including correlation in size, space, time and between species from research survey data
Trawl survey data with high spatial and seasonal coverage were analysed using a variant of the Log Gaussian Cox Process (LGCP) statistical model to estimate unbiased relative fish densities. The model estimates correlations between observations according to time, space, and fish size and includes zero observations and over-dispersion. The model utilises the fact the correlation between numbers of fish caught increases when the distance in space and time between the fish decreases, and the correlation between size groups in a haul increases when the difference in size decreases. Here the model is extended in two ways. Instead of assuming a natural scale size correlation, the model is further developed to allow for a transformed length scale. Furthermore, in the present application, the spatial- and size-dependent correlation between species was included. For cod (Gadus morhua) and whiting (Merlangius merlangus), a common structured size correlation was fitted, and a separable structure between the time and space-size correlation was found for each species, whereas more complex structures were required to describe the correlation between species (and space-size). The within-species time correlation is strong, whereas the correlations between the species are weaker over time but strong within the year
Administrators in higher education: organizational expansion in a transforming institution
Recent European research has revealed growth in the number of administrators and professionals across different sections of universities—a long established trend in US universities. We build on this research by investigating the factors associated with variation in the proportion of administrators across 761 Higher Education Institutions (HEIs) in 11 European countries. We argue that the enactment of expanded and diversified missions of HE is one of the main factors nurturing universities’ profesional and administrative bodies. Our findings support such an assertion; regardless of geographical and institutional differences, HEIs with high levels of “entrepreneurialism” (e.g. in service provision and external engagement) are characterized by a larger proportion of administrative staff. However, we find no empirical support for arguments citing structural pressures and demands on HEIs due to higher student enrolments, budget cuts or deregulation as engines driving such change. Instead, our results point towards, as argued by neo-institutionalists, the diffusion of formal organization as a model of institutional identity and purpose, which is especially prevalent at high levels of external connectedness
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