1,903 research outputs found
Spitzer Observations of Large Amplitude Variables in the LMC and IC 1613
The 3.6 and 4.5 micron characteristics of AGB variables in the LMC and IC1613
are discussed. For C-rich Mira variables there is a very clear
period-luminosity-colour relation, where the [3.6]-[4.5] colour is associated
with the amount of circumstellar material and correlated with the pulsation
amplitude. The [4.5] period-luminosity relation for dusty stars is
approximately one mag brighter than for their naked counterparts with
comparable periods.Comment: 5 pages, 4 figures, to appear in Proceedings of "Wide-Field
Variability Surveys: A 21st Century Perspective
Calcium-rich Gap Transients: Solving the Calcium Conundrum in the Intracluster Medium
X-ray measurements suggest the abundance of Calcium in the intracluster
medium is higher than can be explained using favored models for core-collapse
and Type Ia supernovae alone. We investigate whether the Calcium conundrum in
the intracluster medium can be alleviated by including a contribution from the
recently discovered subclass of supernovae known as Calcium-rich gap
transients. Although the Calcium-rich gap transients make up only a small
fraction of all supernovae events, we find that their high Calcium yields are
sufficient to reproduce the X-ray measurements found for nearby rich clusters.
We find the goodness-of-fit metric improves from 84 to 2 by
including this new class. Moreover, Calcium-rich supernovae preferentially
occur in the outskirts of galaxies making it easier for the nucleosynthesis
products of these events to be incorporated in the intracluster medium via
ram-pressure stripping. The discovery of a Calcium-rich gap transients in
clusters and groups far from any individual galaxy suggests supernovae
associated with intracluster stars may play an important role in enriching the
intracluster medium. Calcium-rich gap transients may also help explain
anomalous Calcium abundances in many other astrophysical systems including
individual stars in the Milky Way, the halos of nearby galaxies and the
circumgalactic medium. Our work highlights the importance of considering the
diversity of supernovae types and corresponding yields when modeling the
abundance of the intracluster medium and other gas reservoirs
Student Preferences for Lecturers' Personalities
The present study set out to examine students’ preferences for lecturers’ personality as a function of their classroom behaviour, core self-evaluations and self-rated character strengths. Various hypotheses were tested: first, students’ Big Five traits would significantly predict corresponding personality preferences for lecturers (the matching hypothesis); second, students’ core self-evaluation scores would significantly predict preferences for extraverted, agreeable and conscientious lecturers; and third, self-rated character strengths would also significantly predict extraverted, agreeable and conscientious lecturers. We also investigated difference in preferences among two ethnic groups (South East Asian/Chinese versus Caucasian/British). In all, 264 British students completed four questionnaires. Conscientiousness was the most desired trait in lecturers, followed by agreeableness, extraversion and openness; neuroticism was the least desired trait. Preference for agreeable lecturers was best predicted by all individual difference variables. Caucasian students had a stronger dislike for neurotic lecturers, while Asians had higher preferences for extraverted, open and agreeable lecturers. There was some evidence of the student–lecturer personality match. Limitations and further research options were discussed
Phytoremediation: a tool for restoring land degraded due to opencast coal mining
This research set on a former reclaimed opencast coal spoil in Varteg
Hills, South Wales, UK explores the phytoremediation potential of Alnus
glutinosa (Alder), Betula pendula (Roth) (Birch) and Larix decidua (Larch),
which are commonly used in UK land reclamation, to sequester metals: Zn,
Cd, Mn, Pb and Cu, from mine spoils. This study also compares the abilities
of newly planted trees to sequester metals on a new experimental site, within
the landscape and compares these with those from older plantations on
adjoining land. This chronosequence is used to evaluate the overall impact of
forestation on metals levels in soils over two decades. Metal concentrations
in soil were measured over three years and those in tree leaves were
measured over two years.
The majority of the samples examined lie between the UK defined
thresholds for contamination but below levels that trigger immediate action
and treatment. Samples within this range are placed within a new 'critical
soil' category. Mapping the spatial distribution of contaminants across
selected test plots shows the presence of micro-scale contamination
hotspots on these sites. These show that while such sites may, on average,
have sub-critcial levels for metal contamination, they may still contain
sections where contaminants reach very severe levels.
Planting trees in mixes is beneficial because different trees selectively
remove different metal contaminants while some species benefit the soil in
other ways. For example, while Alder leaves showed average concentrations
of Cd, Zn and Mn, their roots also aid nitrogen fixation. Of the five metals
selected for this study, two are known to be highly mobile (CD, Zn), two
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relatively immobile (Pb, Cu) and one is intermediate (Mn). Foliar analysis of
Birch shows consistency in accumulation of Cd and Zn in leaves, while
young Larch needles accumulated the highest concentrations of Mn and Pb.
Correlation between movement of metals in soil and leaves over time,
discovered that the uptake of Mn in Alder and Birch foliar on all plots and
Larch on the new experimental plot is positively correlated to the presence of
Zn in the soil.
Studies of the general effects of forestation on metal concentrations in
soil showed that metal levels declined significantly even on the most recently
planted test sites. On four year old plots a 14-18% decrease in Mn
concentrations and about 8% decrease in Cd and Zn concentrations were
observed. Observations of the soils on the full 18 year chronosequence
found that metal levels declined very significantly (p= 0.003 to 0.0002)
through time. Based on the reduction of metal concentration in soil and
uptake in leaves, it is possible to project 40 - 45 years for concentration of
Mn to reach normal soil levels and about 20 - 25 years for Cd level to reach
normal soil levels, provided the soil is not further disrupted by physical,
chemical or biological activities which may recontaminate the spoil. This
demonstrates, conclusively, that forestation is an effective means of metal
remediation on the moderately contaminated lands produced by opencast
coal-mining in Wales.
Keywords: Opencast coal mining; Phytoremediation; contaminated land;
Heavy metal uptake; Alder; Birch
Intercultural Ministry and Liturgical Celebration: An examination of pastoral ministry and liturgical praxis in light of inclusion, hospitality, and accompaniment within diverse faith communities
How can we create an authentic expression of worship that engenders inclusivity, intercultural, multigenerational, gender-LGBTQ+ inclusivity which celebrates the vision of Vatican II liturgical reforms and is representative of both the local gathered community and the global communion of the faithful
Graph Based Disambiguation of Named Entities using Linked Data
Identifying entities such as people, organizations, songs, or places in natural language texts is needful for semantic search, machine translation, and information extraction. A key challenge is the ambiguity of entity names, requiring robust methods to disambiguate names to the entities registered in a knowledge base. Several approaches aim to tackle this problem, they still achieve poor accuracy. We address this drawback by presenting a novel knowledge-base-agnostic approach for named entity disambiguation. Our approach includes the HITS algorithm combined with label expansion strategies and string similarity measure like the n-gram similarity. Based on this combination, we can efficiently detect the correct URIs for a given set of named entities within an input text
Synergistic Effect of Garcinol and Curcumin on Antiproliferative and Apoptotic Activity in Pancreatic Cancer Cells
Pancreatic cancer (PaCa) is a major health concern due to its aggressiveness and early metastasis. Current treatments for PaCa are limited by development of resistance against therapy. As an alternative strategy, we assessed the combinatorial effect of dietary compounds, garcinol and curcumin, on human PaCa cells (BxPC-3 and Panc-1). A significant (P < 0.05) dose-dependent reduction in cell viability and increase in apoptosis were observed in both cell lines as compared to untreated controls. A combination index (CI) value < 1, for a two-way comparison of curcumin and garcinol, suggests synergism. The potency (Dm) of the combination of garcinol and curcumin was 2 to 10 fold that of the individual agents. This indicates that curcumin and garcinol in combination exhibit a high level of synergism, with enhanced bioactivity, thereby reducing the required effective dose required for each individually. This combinatorial strategy may hold promise in future development of therapies against PaCa
Geo-Skip List Data Structure ? Implementation and Solving Spatial Queries
A major portion of the queries fired on the internet have spatial keywords in them, the storage and retrieval of spatial data has become an important task in today?s era. Given a geographic query that is composed of query keywords and a location, a geographic search engine retrieves documents that are the most textually and spatially relevant to the query keywords and the location, respectively, and ranks the retrieved documents according to their joint textual and spatial relevance to the query. The lack of an efficient index that can simultaneously handle both the textual and spatial aspects of the documents makes existing geographic search engines inefficient in answering geographic queries. There are data structures which facilitate storage and retrieval of geographical data like R-trees, R* trees, KD trees etc. We propose Geo-Skip list data structure which is also one such data structure which is inspired from the skip list data structure. It is simple, dynamic, partly deterministic and partly randomized data structure. This structure brings out the hierarchy of administrative divisions of a region very well. Also it shows an improvement in the search efficiency as compared with R-trees. In this paper, we propose algorithms for the implementation of basic spatial queries with the help of Geo-Skip List data structure ? namely, point query, range query, finding the nearest neighbour query and kth nearest neighbour query
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