1,942 research outputs found
Wikipedia as an encyclopaedia of life
In his 2003 essay E O Wilson outlined his vision for an “encyclopaedia of life” comprising “an electronic page for each species of organism on Earth”, each page containing “the scientific name of the species, a pictorial or genomic presentation of the primary type specimen on which its name is based, and a summary of its diagnostic traits.” Although the “quiet revolution” in biodiversity informatics has generated numerous online resources, including some directly inspired by Wilson's essay (e.g., "http://ispecies.org":http://ispecies.org, "http://www.eol.org":http://www.eol.org), we are still some way from the goal of having available online all relevant information about a species, such as its taxonomy, evolutionary history, genomics, morphology, ecology, and behaviour. While the biodiversity community has been developing a plethora of databases, some with overlapping goals and duplicated content, Wikipedia has been slowly growing to the point where it now has over 100,000 pages on biological taxa. My goal in this essay is to explore the idea that, largely independent of the efforts of biodiversity informatics and well-funded international efforts, Wikipedia ("http://en.wikipedia.org/wiki/Main_Page":http://en.wikipedia.org/wiki/Main_Page) has emerged as potentially the best platform for fulfilling E O Wilson’s vision
A combinatorial approach to knot recognition
This is a report on our ongoing research on a combinatorial approach to knot
recognition, using coloring of knots by certain algebraic objects called
quandles. The aim of the paper is to summarize the mathematical theory of knot
coloring in a compact, accessible manner, and to show how to use it for
computational purposes. In particular, we address how to determine colorability
of a knot, and propose to use SAT solving to search for colorings. The
computational complexity of the problem, both in theory and in our
implementation, is discussed. In the last part, we explain how coloring can be
utilized in knot recognition
Spinal involvement in mucopolysaccharidosis IVA (Morquio-Brailsford or Morquio A syndrome): presentation, diagnosis and management.
Mucopolysaccharidosis IVA (MPS IVA), also known as Morquio-Brailsford or Morquio A syndrome, is a lysosomal storage disorder caused by a deficiency of the enzyme N-acetyl-galactosamine-6-sulphate sulphatase (GALNS). MPS IVA is multisystemic but manifests primarily as a progressive skeletal dysplasia. Spinal involvement is a major cause of morbidity and mortality in MPS IVA. Early diagnosis and timely treatment of problems involving the spine are critical in preventing or arresting neurological deterioration and loss of function. This review details the spinal manifestations of MPS IVA and describes the tools used to diagnose and monitor spinal involvement. The relative utility of radiography, computed tomography (CT) and magnetic resonance imaging (MRI) for the evaluation of cervical spine instability, stenosis, and cord compression is discussed. Surgical interventions, anaesthetic considerations, and the use of neurophysiological monitoring during procedures performed under general anaesthesia are reviewed. Recommendations for regular radiological imaging and neurologic assessments are presented, and the need for a more standardized approach for evaluating and managing spinal involvement in MPS IVA is addressed
Decolonising Philosophy
Based on Maldonado-Torres’s formulation of the term, we conceive the decolonial turn as a form of liberating and decolonising reason beyond the liberal and Enlightened emancipation of rationality, and beyond the more radical Euro-critiques that have failed to consistently challenge the legacies of Eurocentrism and white male heteronormativity (often Eurocentric critiques of Eurocentrism). We complement Maldonado-Torres’s account of the decolonial turn in philosophy, theory and critique by providing an analysis of the trajectories of academic philosophy and clarifying the relevance of decolonising philosophy and of the decolonial turn for current efforts in transforming philosophy in face of the challenges of social movements such as the Third World Liberation Front and Black Lives Matter in the United States, and Rhodes Must Fall in South Africa and England. After a brief analysis of the trajectory and current status of philosophy as a discipline in the modern Western research university, we provide examples of the decolonial turn and of decolonising philosophy in three areas: the engagement with (1) Asian and (2) Latin American philosophies, and (3) debates in the philosophy of race and gender
Prostate involvement during sexually transmitted infections as measured by prostate-specific antigen concentration
Background:We investigated prostate involvement during sexually transmitted infections by measuring serum prostate-specific antigen (PSA) as a marker of prostate infection, inflammation, and/or cell damage in young, male US military members.Methods:We measured PSA before and during infection for 299 chlamydia, 112 gonorrhoea, and 59 non-chlamydial, non-gonococcal urethritis (NCNGU) cases, and 256 controls.Results:Chlamydia and gonorrhoea, but not NCNGU, cases were more likely to have a large rise (⩾40%) in PSA than controls (33.6%, 19.1%, and 8.2% vs 8.8%, P<0.0001, 0.021, and 0.92, respectively).Conclusion:Chlamydia and gonorrhoea may infect the prostate of some infected men
Genome wide mapping reveals PDE4B as an IL-2 induced STAT5 target gene in activated human PBMCs and lymphoid cancer cells
IL-2 is the primary growth factor for promoting survival and proliferation of activated T cells that occurs following engagement of the Janus Kinase (JAK)1-3/and Signal Transducer and Activator of Transcription (STAT) 5 signaling pathway. STAT5 has two isoforms: STAT5A and STAT5B ( commonly referred to as STAT5) which, in T cells, play redundant roles transcribing cell cycle and survival genes. As such, inhibition of STAT5 by a variety of mechanisms can rapidly induce apoptosis in certain lymphoid tumor cells, suggesting that it and its target genes represent therapeutic targets to control certain lymphoid diseases. To search for these molecules we aligned IL-2 regulated genes detected by Affymetrix gene expression microarrays with the STAT5 cistrome identified by chip-on-ChIP analysis in an IL-2-dependent human leukemia cell line, Kit225. Select overlapping genes were then validated using qRT(2)PCR medium-throughput arrays in human PHA-activated PBMCs. Of 19 putative genes, one key regulator of T cell receptor signaling, PDE4B, was identified as a novel target, which was readily up-regulated at the protein level (3 h) in IL-2 stimulated, activated human PBMCs. Surprisingly, only purified CD8+ primary T-cells expressed PDE4B, but not CD4+ cells. Moreover, PDE4B was found to be highly expressed in CD4+ lymphoid cancer cells, which suggests that it may represent a physiological role unique to the CD8+ and lymphoid cancer cells and thus might represent a target for pharmaceutical intervention for certain lymphoid diseases
Assessing L2 vocabulary depth with word associates format tests: issues, findings, and suggestions
Word Associates Format (WAF) tests are often used to measure second language learners’ vocabulary depth with a focus on their network knowledge. Yet, there were often many variations in the specific forms of the tests and the ways they were used, which tended to have an impact on learners’ response behaviors and, more importantly, the psychometric properties of the tests. This paper reviews the general practices, key issues, and research findings that pertain to WAF tests in four major areas, including the design features of WAF tests, conditions for test administration, scoring methods, and test-taker characteristics. In each area, a set of variables is identified and described with relevant research findings also presented and discussed. Around eight topics, the General Discussion section provides some suggestions and directions for the development of WAF tests and the use of them as research tools in the future. This paper is hoped to help researchers become better aware that the results generated by a WAF test may vary depending on what specific design the test has, how it is administered and scored, and who the learners are, and consequently, make better decisions in their research that involves a WAF test
The Temporal Signature of Memories: Identification of a General Mechanism for Dynamic Memory Replay in Humans
Reinstatement of dynamic memories requires the replay of neural patterns that unfold over
time in a similar manner as during perception. However, little is known about the mechanisms
that guide such a temporally structured replay in humans, because previous studies
used either unsuitable methods or paradigms to address this question. Here, we overcome
these limitations by developing a new analysis method to detect the replay of temporal patterns
in a paradigm that requires participants to mentally replay short sound or video clips.
We show that memory reinstatement is accompanied by a decrease of low-frequency (8
Hz) power, which carries a temporal phase signature of the replayed stimulus. These replay
effects were evident in the visual as well as in the auditory domain and were localized to
sensory-specific regions. These results suggest low-frequency phase to be a domain-general
mechanism that orchestrates dynamic memory replay in humans
Frequency-specific hippocampal-prefrontal interactions during associative learning
Much of our knowledge of the world depends on learning associations (for example, face-name), for which the hippocampus (HPC) and prefrontal cortex (PFC) are critical. HPC-PFC interactions have rarely been studied in monkeys, whose cognitive and mnemonic abilities are akin to those of humans. We found functional differences and frequency-specific interactions between HPC and PFC of monkeys learning object pair associations, an animal model of human explicit memory. PFC spiking activity reflected learning in parallel with behavioral performance, whereas HPC neurons reflected feedback about whether trial-and-error guesses were correct or incorrect. Theta-band HPC-PFC synchrony was stronger after errors, was driven primarily by PFC to HPC directional influences and decreased with learning. In contrast, alpha/beta-band synchrony was stronger after correct trials, was driven more by HPC and increased with learning. Rapid object associative learning may occur in PFC, whereas HPC may guide neocortical plasticity by signaling success or failure via oscillatory synchrony in different frequency bands.National Institute of Mental Health (U.S.) (Conte Center Grant P50-MH094263-03)National Institute of Mental Health (U.S.) (Fellowship F32-MH081507)Picower Foundatio
The Evolution of Compact Binary Star Systems
We review the formation and evolution of compact binary stars consisting of
white dwarfs (WDs), neutron stars (NSs), and black holes (BHs). Binary NSs and
BHs are thought to be the primary astrophysical sources of gravitational waves
(GWs) within the frequency band of ground-based detectors, while compact
binaries of WDs are important sources of GWs at lower frequencies to be covered
by space interferometers (LISA). Major uncertainties in the current
understanding of properties of NSs and BHs most relevant to the GW studies are
discussed, including the treatment of the natal kicks which compact stellar
remnants acquire during the core collapse of massive stars and the common
envelope phase of binary evolution. We discuss the coalescence rates of binary
NSs and BHs and prospects for their detections, the formation and evolution of
binary WDs and their observational manifestations. Special attention is given
to AM CVn-stars -- compact binaries in which the Roche lobe is filled by
another WD or a low-mass partially degenerate helium-star, as these stars are
thought to be the best LISA verification binary GW sources.Comment: 105 pages, 18 figure
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