3,641 research outputs found
In-the-wild residual data research and privacy
As the world becomes increasingly dependent on technology, researchers endeavor to understand how technology is used, the impact it has on everyday life and the life-cycle and span of digital information. In doing so, researchers are
increasingly gathering `real-world' or `in the wild' residual data, obtained from a variety of sources without the explicit consent of the original owners.
This data gathering raises significant concerns regarding privacy, ethics and legislation, as well as practical considerations concerning investigator training, data storage, overall security and disposal. This paper surveys recent studies of residual data gathered in the wild and analyses the challenges that were faced. Taking these insights, the paper presents a compendium of practices
for addressing the issues that arise in in the wild residual data research. The practices presented in this paper can be used to critique current projects and assess the feasibility of proposed future research
Artisanal materials for sustainable construction in developing countries
Sustainable construction is a major challenge to developing countries more so when it comes to the use of artisanal materials in the construction process. This review identifies and examines the challenges facing developing countries in this respect: environmental degradation, poverty, informal settlements, inappropriate regulatory mechanism, inappropriate technology, and neglect in research and development debates. It notes that research and development at local level is necessary for addressing the challenges posed by the use of artisanal materials from sustainable development point of view. Above all, it recommends research into the area of artisanal materials and sustainable construction
The diagnostic performance of routinely acquired and reported computed tomography imaging in patients presenting with suspected pleural malignancy
Objectives:
Contrast-enhanced computed tomography (CT) provides essential cross-sectional imaging data in patients with suspected pleural malignancy (PM). The performance of CT in routine practice may be lower than in previously reported research. We assessed this relative to ‘real-life’ factors including use of early arterial-phase contrast enhancement (by CT pulmonary angiography (CTPA)) and non-specialist radiology reporting.
Materials and methods:
Routinely acquired and reported CT scans in patients recruited to the DIAPHRAGM study (a prospective, multi-centre observational study of mesothelioma biomarkers) between January 2014 and April 2016 were retrospectively reviewed. CT reports were classified as malignant if they included specific terms e.g. “suspicious of malignancy”, “stage M1a” and benign if others were used e.g. “indeterminate”, “no cause identified”. All patients followed a standard diagnostic algorithm. The diagnostic performance of CT (overall and based on the above factors) was assessed using 2 × 2 Contingency Tables.
Results:
30/345 (9%) eligible patients were excluded (non-contrast (n = 13) or non-contiguous CT (n = 4), incomplete follow-up (n = 13)). 195/315 (62%) patients studied had PM; 90% were cyto-histologically confirmed. 172/315 (55%) presented as an acute admission, of whom 31/172 (18%) had CTPA. Overall, CT sensitivity was 58% (95% CI 51–65%); specificity was 80% (95% CI 72–87%). Sensitivity of CTPA (performed in 31/315 (10%)) was lower (27% (95% CI 9–53%)) than venous-phase CT (61% (95% CI 53–68%) p = 0.0056). Sensitivity of specialist thoracic radiologist reporting was higher (68% (95% CI 55–79%)) than non-specialist reporting (53% (95% CI 44–62%) p = 0.0488). Specificity was not significantly different.
Conclusion:
The diagnostic performance of CT in routine clinical practice is insufficient to exclude or confirm PM. A benign CT report should not dissuade pleural sampling where the presence of primary or secondary pleural malignancy would alter management. Sensitivity is lower with non-thoracic radiology reporting and particularly low using CTPA
Quantified HI Morphology VII: star-formation and tidal influence on local dwarf HI morphology
Scale-invariant morphology parameters applied to atomic hydrogen maps (HI) of
galaxies can be used to quantify the effects of tidal interaction or
star-formation on the ISM. Here we apply these parameters, Concentration,
Asymmetry, Smoothness, Gini, M20, and the GM parameter, to two public surveys
of nearby dwarf galaxies, the VLA-ANGST and LITTLE-THINGS survey, to explore
whether tidal interaction or the ongoing or past star-formation is a dominant
force shaping the HI disk of these dwarfs.
Previously, HI morphological criteria were identified for ongoing
spiral-spiral interactions. When we apply these to the Irregular dwarf
population, they either select almost all or none of the population. We find
that only the Asymmetry-based criteria can be used to identify very isolated
dwarfs (i.e., these have a low tidal indication). Otherwise, there is little or
no relation between the level of tidal interaction and the HI morphology. We
compare the HI morphology to three star-formation rates based on either Halpha,
FUV or the resolved stellar population, probing different star-formation
time-scales.
The HI morphology parameters that trace the inequality of the distribution,
the Gini, GM, and M20 parameters, correlate weakly with all these
star-formation rates. This is in line with the picture that local physics
dominates the ISM appearance and not tidal effects. Finally, we compare the
SDSS measures of star-formation and stellar mass to the HI morphological
parameters for all four HI surveys. In the two lower-resolution HI surveys
(12"), there is no relation between star-formation measures and HI morphology.
The morphology of the two high-resolution HI surveys (6"), the Asymmetry,
Smoothness, Gini, M20, and GM, do show a link to the total star-formation, but
a weak one.Comment: 26 figures, 4 tables, two appendices. Third appendix (HI maps of all
galaxies) omitted. Accepted by MNRA
First Results from Photon Multiplicity Detector at RHIC
We present the first measurement of multiplicity and pseudorapidity
distributions of photons in the pseudorapidity region 2.3 < eta < 3.7 for
different centralities in Au + Au collisions at sqrt{s_NN} = 62.4 GeV. The
pseudorapidity distribution of photons, dominated by neutral pion decays, has
been compared to those of identified charged pions, photons, and inclusive
charged particles from heavy ion and nucleon-nucleon collisions at various
energies. Scaling of photon yield with number of participating nucleons and
limiting fragmentation scenario for inclusive photon production has been
studied.Comment: Talk given at 5th International Conference on Physics and
Astrophysics of Quark Gluon Plasma (February 8 - 12, 2005); 4 pages and 6
figure
Towards a generalisation of formal concept analysis for data mining purposes
In this paper we justify the need for a generalisation of Formal
Concept Analysis for the purpose of data mining and begin the
synthesis of such theory. For that purpose, we first review semirings and
semimodules over semirings as the appropriate objects to use in abstracting
the Boolean algebra and the notion of extents and intents, respectively.
We later bring to bear powerful theorems developed in the field
of linear algebra over idempotent semimodules to try to build a Fundamental
Theorem for K-Formal Concept Analysis, where K is a type of
idempotent semiring. Finally, we try to put Formal Concept Analysis in
new perspective by considering it as a concrete instance of the theory
developed
Properties of particle production at large transverse momentum in Au+Au and Cu+Cu collisions at RHIC
We present the incident energy and system size dependence of the pT spectra
for charged pions, protons, and anti-protons using Au+Au and Cu+Cu collisions
at Sqrt(sNN) = 62.4 and 200 GeV in STAR experiment at RHIC. Through these
measurements in the pT range of 0.2 < pT < 10 GeV/c we conduct a systematic
study of the beam energy, system size and particle species dependence of
nuclear modification factors and address specific predictions from the quark
coalescence models regarding the beam energy dependence of baryon enhancement
in the intermediate pT (2 < pT < 6 GeV/c) region.Comment: Talk given at 19th International Conference on Ultra-relativistic
Nucleus-Nucleus Collisions: Quark Matter 2006 (QM 2006), Shanghai, China,
14-20 Nov. 200
Quantified Morphology of HI Disks in the Universe
he upcoming new perspective of the high redshift Universe in the 21 cm line
of atomic hydrogen opens possibilities to explore topics of spiral disk
evolution, hitherto reserved for the optical regime. The growth of spiral gas
disks over Cosmic time can be explored with the new generation of radio
telescopes, notably the SKA, and its precursors, as accurately as with the
Hubble Space Telescope for stellar disks. Since the atomic hydrogen gas is the
building block of these disks, it should trace their formation accurately.
Morphology of HI disks can now equally be quantified over Cosmic time. In
studies of HST deep fields, the optical or UV morphology of high-redshift
galaxy disks have been characterized using a few quantities: concentration (C),
asymmetry (A), smoothness (S), second-order-moment (M20), the GINI coefficient
(G), and Ellipticity (E). We have applied these parameters across wavelengths
and compared them to the HI morphology over the THINGS sample. NGC 3184, an
unperturbed disk, and NGC 5194, the canonical 3:1 interaction, serve as
examples for quantified morphology. We find that morphology parameters
determined in HI are as good or better a tracer of interaction compared to
those in any other wavelength, notably in Asymmetry, Gini and M20. This opens
the possibility of using them in the parameterization pipeline for SKA
precursor catalogues to select interacting or harassed galaxies from their HI
morphology. Asymmetry, Gini and M20 may be redefined for use on data-cubes
rather than HI column density image.Comment: 6 pages, 3 figures, proceeding of the conference "Panoramic Radio
Astronomy: Wide-field 1-2 GHz research on galaxy evolution", June 02 - 05
2009, Groningen, update after small edit
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