141 research outputs found
¿Existe un sesgo en la participación y visibilidad de las mujeres en ecología? Una comparación entre los congresos ibérico y suizo
Women are still under-represented in science and technology because there is a bias in the different evaluation processes from the admission of oral communications at conferences to the access to more qualified positions. In this study, we compared the participation and visibility of female ecologists in the IV Iberian Ecological Conference (CIE4) with the Annual Swiss Conference on Ecology, Evolution, Systematics, Biogeography and Conservation (Biology16) where a method of blind evaluation was applied.
In both conferences, and after active selection by conference committees, male delegates presented proportionately more regular oral contributions than female ones, although these differences were marginally significant. In the Biology16, this bias was due to lower female applicants for oral contributions, and in the CIE4, to a lower selection rate of female oral contributions. In the CIE4, the higher male presence in oral contributions was consistent with male greater visibility, whereas female visibility was higher in the Biology16. This different visibility was caused by contrasting selection for invited speakers; being male researches preferentially invited at the CIE4, but female ones at the Biology16.
Implementing a blind review system of contributions and active policies to promote the participation of women as invited speakers may reduce the differences in visibility and could contribute in the medium term to eliminate the bias against women in the selection of oral contributions at the Iberian conferences
Collective Memory for American Leaders: Measuring Recognition for the Names and Faces of the US Presidents
Collective memory studies show that Americans remember their presidents in a predictable pattern, which can be described as a serial position curve with an additional spike for Abraham Lincoln. However, all prior studies have tested Americans’ collective memory for the presidents by their names. How well do Americans know the faces of the presidents? In two experiments, we investigated presidential facial recognition and compared facial recognition to name recognition. In Experiment 1, an online sample judged whether each of the official portraits of the US presidents and similar portraits of nonpresidents depicted a US president. The facial recognition rate (around 60%) was lower than the name recognition rate in past research (88%), but the overall pattern still fit a serial position curve. Some nonpresidents, such as Alexander Hamilton, were still falsely identified as presidents at high rates. In Experiment 2, a college sample completed a recognition task composed of both faces and names to directly compare the recognition rates. As predicted, subjects recognized the names of the presidents more frequently than the faces. Some presidents were frequently identified by their names but not by their faces (e.g. John Quincy Adams), while others were the opposite (e.g. Calvin Coolidge). Together, our studies show that Americans’ memory for the faces of the presidents is somewhat worse than their memory for the names of the presidents but still follows the same pattern, indicating that collective memories contain more than just verbal information
Castleman's disease in the head of the pancreas: report of a rare clinical entity and current perspective on diagnosis, treatment, and outcome
<p>Abstract</p> <p>Background</p> <p>Castleman's disease of the pancreas is a very rare condition that may resemble more common disease entities as well as pancreatic cancer.</p> <p>Case presentation</p> <p>Here we report the case of a 58-year-old African American male with an incidentally discovered lesion in the head of the pancreas. The specimen from his pancreaticoduodectomy contained a protuberant, encapsulated mass, exhibiting microscopic features most consistent with localized/unicentric Castleman's disease. These included florid follicular hyperplasia with mantle/marginal zone hyperplasia along with focal progressive transformation of germinal centers admixed with involuted germinal centers.</p> <p>Conclusion</p> <p>To date, eight cases of Castleman's disease associated with the pancreas have been described in the world literature. We report the first case of unicentric disease situated within the head of the pancreas. In addition, we discuss the diagnostic dilemma Castleman's disease may present to the pancreatic surgeon and review current data on pathogenesis, treatment, and outcome.</p
The next Generation of Action Ecology: Novel Approaches towards Global Ecological Research
Advances in the acquisition and dissemination of knowledge over the last decade have dramatically reshaped the way that ecological research is conducted. The advent of large, technology-based resources such as iNaturalist, Genbank, or the Global Biodiversity Information Facility (GBIF) allow ecologists to work at spatio-temporal scales previously unimaginable. This has generated a new approach in ecological research: one that relies on large datasets and rapid synthesis for theory testing and development, and findings that provide specific recommendations to policymakers and managers. This new approach has been termed action ecology, and here we aim to expand on earlier definitions to delineate its characteristics so as to distinguish it from related subfields in applied ecology and ecological management. Our new, more nuanced definition describes action ecology as ecological research that is (1) explicitly motivated by the need for immediate insights into current, pressing problems, (2) collaborative and transdisciplinary, incorporating sociological in addition to ecological considerations throughout all steps of the research, (3) technology-mediated, innovative, and aggregative (i.e., reliant on ‘big data\u27), and (4) designed and disseminated with the intention to inform policy and management. We provide tangible examples of existing work in the domain of action ecology, and offer suggestions for its implementation and future growth, with explicit recommendations for individuals, research institutions, and ecological societies
On the Relationship Between the Critical Temperature and the London Penetration Depth in Layered Organic Superconductors
We present an analysis of previously published measurements of the London
penetration depth of layered organic superconductors. The predictions of the
BCS theory of superconductivity are shown to disagree with the measured zero
temperature, in plane, London penetration depth by up to two orders of
magnitude. We find that fluctuations in the phase of the superconducting order
parameter do not determine the superconducting critical temperature as the
critical temperature predicted for a Kosterlitz--Thouless transition is more
than an order of magnitude greater than is found experimentally for some
materials. This places constraints on theories of superconductivity in these
materials.Comment: 5 pages, 1 figur
‘The price is different depending on whether you want a receipt or not’: examining the purchasing of goods and services from the informal economy in South-East Europe
Research on the informal economy has largely focussed on supply-side issues, addressing questions like what motivates individuals to work in the informal economy and how can governments tackle this phenomenon. To date, much less attention has been given to demand-side aspects, examining issues around who purchases goods and services from the informal economy, why, and to what extent there are variations according to demographic, socio-economic and geographic dimensions. This paper addresses this imbalance by examining the purchasing of goods and services from the informal economy in South-East Europe. Firstly, this paper identifies the prevalence of such informal purchasing in South-East Europe as well as who undertakes such purchasing. Next, it examines the relative significance of cost factors, social factors and failures in the formal economy, in motivating such purchasing. Finally, it explores variability in the significance of these motivators based on individual-level factors, within and across three South-East European countries
The plausibility of a role for mercury in the etiology of autism: a cellular perspective
Autism is defined by a behavioral set of stereotypic and repetitious behavioral patterns in combination with social and communication deficits. There is emerging evidence supporting the hypothesis that autism may result from a combination of genetic susceptibility and exposure to environmental toxins at critical moments in development. Mercury (Hg) is recognized as a ubiquitous environmental neurotoxin and there is mounting evidence linking it to neurodevelopmental disorders, including autism. Of course, the evidence is not derived from experimental trials with humans but rather from methods focusing on biomarkers of Hg damage, measurements of Hg exposure, epidemiological data, and animal studies. For ethical reasons, controlled Hg exposure in humans will never be conducted. Therefore, to properly evaluate the Hg-autism etiological hypothesis, it is essential to first establish the biological plausibility of the hypothesis. This review examines the plausibility of Hg as the primary etiological agent driving the cellular mechanisms by which Hg-induced neurotoxicity may result in the physiological attributes of autism. Key areas of focus include: (1) route and cellular mechanisms of Hg exposure in autism; (2) current research and examples of possible genetic variables that are linked to both Hg sensitivity and autism; (3) the role Hg may play as an environmental toxin fueling the oxidative stress found in autism; (4) role of mitochondrial dysfunction; and (5) possible role of Hg in abnormal neuroexcitory and excitotoxity that may play a role in the immune dysregulation found in autism. Future research directions that would assist in addressing the gaps in our knowledge are proposed
Evidence for structural and electronic instabilities at intermediate temperatures in -(BEDT-TTF)X for X=Cu[N(CN)]Cl, Cu[N(CN)]Br and Cu(NCS): Implications for the phase diagram of these quasi-2D organic superconductors
We present high-resolution measurements of the coefficient of thermal
expansion of the quasi-twodimensional
(quasi-2D) salts -(BEDT-TTF)X with X = Cu(NCS), Cu[N(CN)]Br
and Cu[N(CN)]Cl. At intermediate temperatures (B), distinct anomalies
reminiscent of second-order phase transitions have been found at
K and 45 K for the superconducting X = Cu(NCS) and Cu[N(CN)]Br salts,
respectively. Most interestingly, we find that the signs of the uniaxial
pressure coefficients of are strictly anticorrelated with those of
. We propose that marks the transition to a spin-density-wave
(SDW) state forming on minor, quasi-1D parts of the Fermi surface. Our results
are compatible with two competing order parameters that form on disjunct
portions of the Fermi surface. At elevated temperatures (C), all compounds show
anomalies that can be identified with a kinetic, glass-like
transition where, below a characteristic temperature , disorder in the
orientational degrees of freedom of the terminal ethylene groups becomes frozen
in. We argue that the degree of disorder increases on going from the X =
Cu(NCS) to Cu[N(CN)]Br and the Cu[N(CN)]Cl salt. Our results
provide a natural explanation for the unusual time- and cooling-rate
dependencies of the ground-state properties in the hydrogenated and deuterated
Cu[N(CN)]Br salts reported in the literature.Comment: 22 pages, 7 figure
The Dependence of the Superconducting Transition Temperature of Organic Molecular Crystals on Intrinsically Non-Magnetic Disorder: a Signature of either Unconventional Superconductivity or Novel Local Magnetic Moment Formation
We give a theoretical analysis of published experimental studies of the
effects of impurities and disorder on the superconducting transition
temperature, T_c, of the organic molecular crystals kappa-ET_2X and beta-ET_2X
(where ET is bis(ethylenedithio)tetrathiafulvalene and X is an anion eg I_3).
The Abrikosov-Gorkov (AG) formula describes the suppression of T_c both by
magnetic impurities in singlet superconductors, including s-wave
superconductors and by non-magnetic impurities in a non-s-wave superconductor.
We show that various sources of disorder lead to the suppression of T_c as
described by the AG formula. This is confirmed by the excellent fit to the
data, the fact that these materials are in the clean limit and the excellent
agreement between the value of the interlayer hopping integral, t_perp,
calculated from this fit and the value of t_perp found from angular-dependant
magnetoresistance and quantum oscillation experiments. If the disorder is, as
seems most likely, non-magnetic then the pairing state cannot be s-wave. We
show that the cooling rate dependence of the magnetisation is inconsistent with
paramagnetic impurities. Triplet pairing is ruled out by several experiments.
If the disorder is non-magnetic then this implies that l>=2, in which case
Occam's razor suggests that d-wave pairing is realised. Given the proximity of
these materials to an antiferromagnetic Mott transition, it is possible that
the disorder leads to the formation of local magnetic moments via some novel
mechanism. Thus we conclude that either kappa-ET_2X and beta-ET_2X are d-wave
superconductors or else they display a novel mechanism for the formation of
localised moments. We suggest systematic experiments to differentiate between
these scenarios.Comment: 18 pages, 5 figure
Low Temperature Penetration depth of \kappa-(ET)_2Cu[N(CN)_2]Br and \kappa-(ET)_2Cu(NCS)_2
We present high precision measurements of the penetration depth \lambda of
single crystals of \kappa-(ET)_2Cu[N(CN)2]Br and \kappa-(ET)_2Cu(NCS)_2 at
temperature down to 0.4 K. We find that, at low temperatures, the in-plane
penetration depth varies as a fractional power law, \lambda\sim T^1.5. W hilst
this may be taken as evidence for novel bose excitation processes, we show that
the data are also consistent with a quasi-linear variation of the superfluid
density, as is expected for a d-wave superconductor with impurities. Our data
for the interplane penetration depth show similar features and give a direct
measurement of the absolute value, \lambda(0)=100\pm 20 \mu m.Comment: 4 pages, 4 postscript figure
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