861 research outputs found
Assessing the reliability of retrospective reports of adverse childhood experiences among adolescents with documented childhood maltreatment
The literature suggests that childhood maltreatment
is related to a higher probability of developing psychopathology
and disease in adulthood. However, some authors have
questioned the reliability of self-reports of maltreatment, suggesting
that psychopathology at the time of evaluation affects
self-reports. We evaluated the reliability of the self-reports of
79 young adults who were identified in childhood by Child
Protective Services by comparing two moments of evaluation.
Psychological and physical symptoms were tested to evaluate
their interference with the reports. We found good to excellent
agreement, with no significant correlation between the changes
in self-reported experiences and the changes in physical and
psychological symptoms, suggesting that the reliability of
reports is not related to the health state at the time of the report
ARPES: A probe of electronic correlations
Angle-resolved photoemission spectroscopy (ARPES) is one of the most direct
methods of studying the electronic structure of solids. By measuring the
kinetic energy and angular distribution of the electrons photoemitted from a
sample illuminated with sufficiently high-energy radiation, one can gain
information on both the energy and momentum of the electrons propagating inside
a material. This is of vital importance in elucidating the connection between
electronic, magnetic, and chemical structure of solids, in particular for those
complex systems which cannot be appropriately described within the
independent-particle picture. Among the various classes of complex systems, of
great interest are the transition metal oxides, which have been at the center
stage in condensed matter physics for the last four decades. Following a
general introduction to the topic, we will lay the theoretical basis needed to
understand the pivotal role of ARPES in the study of such systems. After a
brief overview on the state-of-the-art capabilities of the technique, we will
review some of the most interesting and relevant case studies of the novel
physics revealed by ARPES in 3d-, 4d- and 5d-based oxides.Comment: Chapter to appear in "Strongly Correlated Systems: Experimental
Techniques", edited by A. Avella and F. Mancini, Springer Series in
Solid-State Sciences (2013). A high-resolution version can be found at:
http://www.phas.ubc.ca/~quantmat/ARPES/PUBLICATIONS/Reviews/ARPES_Springer.pdf.
arXiv admin note: text overlap with arXiv:cond-mat/0307085,
arXiv:cond-mat/020850
A proposal for a coordinated effort for the determination of brainwide neuroanatomical connectivity in model organisms at a mesoscopic scale
In this era of complete genomes, our knowledge of neuroanatomical circuitry
remains surprisingly sparse. Such knowledge is however critical both for basic
and clinical research into brain function. Here we advocate for a concerted
effort to fill this gap, through systematic, experimental mapping of neural
circuits at a mesoscopic scale of resolution suitable for comprehensive,
brain-wide coverage, using injections of tracers or viral vectors. We detail
the scientific and medical rationale and briefly review existing knowledge and
experimental techniques. We define a set of desiderata, including brain-wide
coverage; validated and extensible experimental techniques suitable for
standardization and automation; centralized, open access data repository;
compatibility with existing resources, and tractability with current
informatics technology. We discuss a hypothetical but tractable plan for mouse,
additional efforts for the macaque, and technique development for human. We
estimate that the mouse connectivity project could be completed within five
years with a comparatively modest budget.Comment: 41 page
A finer grained approach to psychological capital and work performance
Purpose
Psychological capital is a set of personal resources comprised by hope, efficacy, optimism, and resilience, which previous research has supported as being valuable for general work performance. However, in today’s organizations, a multidimensional approach is required to understanding work performance, thus, we aimed to determine whether psychological capital improves proficiency, adaptivity, and proactivity, and also whether hope, efficiency, resilience, and optimism have a differential contribution to the same outcomes. Analyzing the temporal meaning of each psychological capital dimension, this paper theorizes the relative weights of psychological capital dimensions on proficiency, adaptivity, and proactivity, proposing also that higher relative weight dimensions are helpful to cope with job demands and perform well.
Methodology
Two survey studies, the first based on cross-sectional data and the second on two waves of data, were conducted with employees from diverse organizations, who provided measures of their psychological capital, work performance, and job demands. Data was modeled with regression analysis together with relative weights analysis.
Findings
Relative weights for dimensions of psychological capital were supported as having remarkable unique contributions for proficient, adaptive, and proactive behavior, particularly when job demands were high.
Originality/Value
We concluded that organizations facing high job demands should implement actions to enhance psychological capital dimensions; however, those actions should focus on the specific criterion of performance of interest
A Review of Sociological Issues in Fire Safety Regulation
This paper presents an overview of contemporary sociological issues in fire safety. The most obviously social aspects of fire safety—those that relate to the socioeconomic distribution of fire casualties and damage—are discussed first. The means that society uses to mitigate fire risks through regulation are treated next; focusing on the shift towards fire engineered solutions and the particular challenges this poses for the social distribution and communication of fire safety knowledge and expertise. Finally, the social construction of fire safety knowledge is discussed, raising questions about whether the confidence in the application of this knowledge by the full range of participants in the fire safety design and approvals process is always justified, given the specific assumptions involved in both the production of the knowledge and its extension to applications significantly removed from the original knowledge production; and the requisite competence that is therefore needed to apply this knowledge. The overarching objective is to argue that the fire safety professions ought to be more reflexive and informed about the nature of the knowledge and expertise that they develop and apply, and to suggest that fire safety scientists and engineers ought to actively collaborate with social scientists in research designed to study the way people interact with fire safety technology
Ulk4 regulates GABAergic signaling and anxiety-related behavior
Excitation/inhibition imbalance has been proposed as a fundamental mechanism in the pathogenesis of neuropsychiatric and neurodevelopmental disorders, in which copy number variations of the Unc-51 like kinase 4 (ULK4) gene encoding a putative Serine/Threonine kinase have been reported in approximately 1/1000 of patients suffering pleiotropic clinical conditions of schizophrenia, depression, autistic spectrum disorder (ASD), developmental delay, language delay, intellectual disability, or behavioral disorder. The current study characterized behavior of heterozygous Ulk4(+/tm1a) mice, demonstrating that Ulk4(+/tm1a) mice displayed no schizophrenia-like behavior in acoustic startle reactivity and prepulse inhibition tests or depressive-like behavior in the Porsolt swim or tail suspension tests. However, Ulk4(+/tm1a) mice exhibited an anxiety-like behavioral phenotype in several tests. Previously identified hypo-anxious (Atp1a2, Ptn, and Mdk) and hyper-anxious (Gria1, Syngap1, and Npy2r) genes were found to be dysregulated accordingly in Ulk4 mutants. Ulk4 was found to be expressed in GABAergic neurons and the Gad67⁺ interneurons were significantly reduced in the hippocampus and basolateral amygdala of Ulk4(+/tm1a) mice. Transcriptome analyses revealed a marked reduction of GABAergic neuronal subtypes, including Pvalb, Sst, Cck, Npy, and Nos3, as well as significant upregulation of GABA receptors, including Gabra1, Gabra3, Gabra4, Gabra5, and Gabrb3. This is the first evidence that Ulk4 plays a major role in regulating GABAergic signaling and anxiety-like behavior, which may have implications for the development of novel anxiolytic treatments
Chemical amplification of magnetic field effects relevant to avian magnetoreception
Magnetic fields as weak as the Earth's can change the yields of radical pair reactions even though the energies involved are orders of magnitude smaller than the thermal energy, kBT, at room temperature. Proposed as the source of the light-dependent magnetic compass in migratory birds, the radical pair mechanism is thought to operate in cryptochrome flavoproteins in the retina. Here we demonstrate that the primary magnetic field effect on flavin photoreactions can be amplified chemically by slow radical termination reactions under conditions of continuous photoexcitation. The nature and origin of the amplification are revealed by studies of the intermolecular flavin–tryptophan and flavin–ascorbic acid photocycles and the closely related intramolecular flavin–tryptophan radical pair in cryptochrome. Amplification factors of up to 5.6 were observed for magnetic fields weaker than 1 mT. Substantial chemical amplification could have a significant impact on the viability of a cryptochrome-based magnetic compass sensor
Nuclear poly(ADP-ribose) activity is a therapeutic target in amyotrophic lateral sclerosis
Abstract Amyotrophic lateral sclerosis (ALS) is a devastating and fatal motor neuron disease. Diagnosis typically occurs in the fifth decade of life and the disease progresses rapidly leading to death within ~ 2–5 years of symptomatic onset. There is no cure, and the few available treatments offer only a modest extension in patient survival. A protein central to ALS is the nuclear RNA/DNA-binding protein, TDP-43. In > 95% of ALS patients, TDP-43 is cleared from the nucleus and forms phosphorylated protein aggregates in the cytoplasm of affected neurons and glia. We recently defined that poly(ADP-ribose) (PAR) activity regulates TDP-43-associated toxicity. PAR is a posttranslational modification that is attached to target proteins by PAR polymerases (PARPs). PARP-1 and PARP-2 are the major enzymes that are active in the nucleus. Here, we uncovered that the motor neurons of the ALS spinal cord were associated with elevated nuclear PAR, suggesting elevated PARP activity. Veliparib, a small-molecule inhibitor of nuclear PARP-1/2, mitigated the formation of cytoplasmic TDP-43 aggregates in mammalian cells. In primary spinal-cord cultures from rat, Veliparib also inhibited TDP-43-associated neuronal death. These studies uncover that PAR activity is misregulated in the ALS spinal cord, and a small-molecular inhibitor of PARP-1/2 activity may have therapeutic potential in the treatment of ALS and related disorders associated with abnormal TDP-43 homeostasis
Selenium isotope evidence for progressive oxidation of the Neoproterozoic biosphere
Neoproterozoic (1,000–542 Myr ago) Earth experienced profound environmental change, including ‘snowball’ glaciations, oxygenation and the appearance of animals. However, an integrated understanding of these events remains elusive, partly because proxies that track subtle oceanic or atmospheric redox trends are lacking. Here we utilize selenium (Se) isotopes as a tracer of Earth redox conditions. We find temporal trends towards lower δ82/76Se values in shales before and after all Neoproterozoic glaciations, which we interpret as incomplete reduction of Se oxyanions. Trends suggest that deep-ocean Se oxyanion concentrations increased because of progressive atmospheric and deep-ocean oxidation. Immediately after the Marinoan glaciation, higher δ82/76Se values superpose the general decline. This may indicate less oxic conditions with lower availability of oxyanions or increased bioproductivity along continental margins that captured heavy seawater δ82/76Se into buried organics. Overall, increased ocean oxidation and atmospheric O2 extended over at least 100 million years, setting the stage for early animal evolution
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