634 research outputs found
Scalable Similarity Search for Molecular Descriptors
Similarity search over chemical compound databases is a fundamental task in
the discovery and design of novel drug-like molecules. Such databases often
encode molecules as non-negative integer vectors, called molecular descriptors,
which represent rich information on various molecular properties. While there
exist efficient indexing structures for searching databases of binary vectors,
solutions for more general integer vectors are in their infancy. In this paper
we present a time- and space- efficient index for the problem that we call the
succinct intervals-splitting tree algorithm for molecular descriptors (SITAd).
Our approach extends efficient methods for binary-vector databases, and uses
ideas from succinct data structures. Our experiments, on a large database of
over 40 million compounds, show SITAd significantly outperforms alternative
approaches in practice.Comment: To be appeared in the Proceedings of SISAP'1
Addressing the psychological impact of infertility risk arising from breast cancer treatment: Education and self-compassion interventions
Breast cancer incidence is increasing globally, including populations of childbearing age. Infertility risk from cancer treatment can negatively impact mental health in breast cancer patients and survivors, in part due to a lack of understanding of the risk and mitigation options ahead of treatment. In this commentary, recent literature on understanding of breast cancer treatment risk to infertility is reviewed, and recommendations are made for improving knowledge for at-risk populations. In addition, we propose a novel integration of self-compassion interventions be applied within breast cancer clinical care, building on groundwork from both breast cancer and primary infertility research areas that indicate the psychological benefits of self-compassion. Considerations for the application of self-compassion interventions to address fertility concerns within breast cancer patient and survivor populations are discussed
Mpemba effect and phase transitions in the adiabatic cooling of water before freezing
An accurate experimental investigation on the Mpemba effect (that is, the
freezing of initially hot water before cold one) is carried out, showing that
in the adiabatic cooling of water a relevant role is played by supercooling as
well as by phase transitions taking place at 6 +/- 1 oC, 3.5 +/- 0.5 oC and 1.3
+/- 0.6 oC, respectively. The last transition, occurring with a non negligible
probability of 0.21, has not been detected earlier. Supported by the
experimental results achieved, a thorough theoretical analysis of supercooling
and such phase transitions, which are interpreted in terms of different
ordering of clusters of molecules in water, is given.Comment: revtex, 4 pages, 2 figure
Sustainability in practice: a case report of an interdisciplinary online student conference
Sustainable development is interdisciplinary and applicable to all Higher Education subject areas. However, in some curricula its importance is overlooked which presents a barrier to the achievement of the United Nation Sustainable Development Goals (SDGs). To address this, we organised a
‘Sustainability in Practice’ online conference that invited students to discuss ‘Sustainability, what's it got to do with me?’. The conference, embraced a transformational education approach and active learning, included keynote speakers, breakout sessions and research posters. Student feedback highlighted that they found the event valuable and inspirational: the knowledge gained and discussions with academics and peers were particularly helpful. Students also
wished for further engagement, emphasising the event's value and impact on their appetite for knowledge. Insights reported will enable other institutions to replicate the conference thereby helping them to develop their own students’ knowledge and facilitate conversations on sustainability, contributing to education for sustainable development and further achieving the SDGs
Fast and easy blind deblurring using an inverse filter and PROBE
PROBE (Progressive Removal of Blur Residual) is a recursive framework for
blind deblurring. Using the elementary modified inverse filter at its core,
PROBE's experimental performance meets or exceeds the state of the art, both
visually and quantitatively. Remarkably, PROBE lends itself to analysis that
reveals its convergence properties. PROBE is motivated by recent ideas on
progressive blind deblurring, but breaks away from previous research by its
simplicity, speed, performance and potential for analysis. PROBE is neither a
functional minimization approach, nor an open-loop sequential method (blur
kernel estimation followed by non-blind deblurring). PROBE is a feedback
scheme, deriving its unique strength from the closed-loop architecture rather
than from the accuracy of its algorithmic components
Positive psychology of Malaysian students: impacts of engagement, motivation, self-compassion and wellbeing on mental health
Malaysia plays a key role in education of the Asia Pacific, expanding its scholarly output rapidly. However, mental health of Malaysian students is challenging, and their help-seeking is low because of stigma. This study explored the relationships between mental health and positive psychological constructs (academic engagement, motivation, self-compassion, and wellbeing), and evaluated the relative contribution of each positive psychological construct to mental health in Malaysian students. An opportunity sample of 153 students completed the measures regarding these constructs. Correlation, regression, and mediation analyses were conducted. Engagement, amotivation, self-compassion, and wellbeing were associated with, and predicted large variance in mental health. Self-compassion was the strongest independent predictor of mental health among all the positive psychological constructs. Findings can imply the strong links between mental health and positive psychology, especially selfcompassion. Moreover, intervention studies to examine the effects of self-compassion training on mental health of Malaysian students appear to be warranted.N/
Cosmic Rays at the highest energies
After a century of observations, we still do not know the origin of cosmic
rays. I will review the current state of cosmic ray observations at the highest
energies, and their implications for proposed acceleration models and secondary
astroparticle fluxes. Possible sources have narrowed down with the confirmation
of a GZK-like spectral feature. The anisotropy observed by the Pierre Auger
Observatory may signal the dawn of particle astronomy raising hopes for high
energy neutrino observations. However, composition related measurements point
to a different interpretation. A clear resolution of this mystery calls for
much larger statistics than the reach of current observatories.Comment: 8 pages, 4 figures, in the Proceedings of TAUP 201
Understanding how children are coping with climate change anxiety by exploring coping strategies and supportive interventions.
Climate change presents a significant threat to both the planet and human prosperity which impacts our physical health and mental well-being. There is an imminent requirement for
significant global action. This means (a) our children have been born into unprecedented times and (b) as future adults, they will find themselves facing the major consequences of climate change. These can negatively affect their mental health and well-being. This paper reports the effect of climate anxiety on this population group through an exploration of coping strategies and supportive interventions. Empowering children to engage in climate action has been identified as a coping strategy. Whilst equipping them with knowledge and resources on climate change and providing safe spaces and experiences in nature are identified as supportive interventions. However, further empirical research evidence is needed to determine the next steps to address the extent of the impact of climate anxiety and prepare our children for the future
Non-variable cosmologically distant gamma-ray emitters as an imprint of propagation of ultra-high-energy protons
The acceleration cites of ultra-high-energy (UHE) protons can be traced by
the footprint left by these particles propagating through cosmic microwave
background (CMB) radiation. Secondary electrons produced in extended region of
several tens of Mpc emit their energy via synchrotron radiation predominantly
in the initial direction of the parent protons. It forms a non-variable and
compact (almost point-like) source of high energy gamma rays. The importance of
this effect is increased for cosmologically distant objects; because of severe
energy losses, UHE protons cannot achieve us even in the case of extremely weak
intergalactic magnetic fields. Moreover, at high redshifts the energy
conversion from protons to secondary particles becomes significantly more
effective due to the denser and more energetic CMB in the past. This increases
the chances of UHE cosmic rays to be traced by the secondary synchrotron gamma
radiation. We discuss the energy budget and the redshift dependence of the
efficiency of energy transfer from UHE protons to synchrotron radiation. The
angular and spectral distributions of radiation in the gamma- and X-ray energy
bands are calculated and discussed in the context of their detectability by
Fermi LAT and Chandra observatories
Oligonucleotide−Oligospermine Conjugates (Zip Nucleic Acids): A Convenient Means of Finely Tuning Hybridization Temperatures
Synthesis of oligonucleotide probes and control of their hybridization temperature are key aspects of polymerase chain reaction (PCR)-based detection of genetic sequences. A straightforward means to approach the last goal is to decrease the repulsion between the polyanionic probe and target strands. To this end, we have developed a versatile automated synthesis of oligonucleotide−oligospermine derivatives that gave fast access to a large variety of compounds. Plots of their hybridization temperatures Tm vs overall charge provided a measure of the impact of interstrand phosphate repulsion (and of spermine-mediated attraction) on the main driving force of duplex formation, i.e., base pairing. It showed that stabilization brought about by excess cationic charges can be of larger absolute magnitude than interstrand repulsion, even in high salt media. Base sequence and conjugation site (3′ or 5′) hardly influenced the effect of spermine on Tm. In typical PCR probe conditions, the Tm increased linearly with the number of grafted spermines (e.g., 6.2 °C per spermine for a decanucleotide probe). The large data set of Tm vs number of spermines and oligonucleotide length allowed us to empirically derive a simple mathematical relation that is accurately predicting the Tm of any oligonucleotide−oligospermine derivative. Zip nucleic acids (ZNA) are thus providing an interesting alternative to locked nucleic acids (LNA) or minor groove binders (MGB) for raising the stability of 8−12-mer oligonucleotides up to ca. 70 °C, the level required for quantitative PCR experiments
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