2,223 research outputs found
Ecology of the Acalypta species occurring in Hungary Insecta Heteroptera Tingidae data to the knowledge on the ground-living Heteroptera of Hungary, No 3
As a third part of a series of papers on the ground-living true bugs of Hungary, the species
belonging to the lace bug genus Acalypta Westwood, 1840 (Insecta: Heteroptera: Tingidae) were studied.
Extensive materials collected with Berlese funnels during about 20 years all over Hungary were
identified. Based on these sporadic data of many years, faunistic notes are given on some Hungarian
species. The seasonal occurrence of the species are discussed. The numbers of specimens of different
Acalypta species collected in diverse plant communities are compared with multivariate methods.
Materials collected with pitfall traps between 1979–1982 at Bugac, Kiskunság National Park were also
processed. In this area, only A. marginata and A. gracilis occurred, both in great number. The temporal
changes of the populations are discussed. Significant differences could be observed between the
microhabitat distribution of the two species: both species occurred in very low number in traps placed out
in patches colonized by dune-slack purple moorgrass meadow; Acalypta gracilis preferred distinctly the
Pannonic dune open grassland patches; A. marginata occurred in almost equal number in Pannonic dune
open grassland and in Pannonic sand puszta patches
Isolated resonances in conductance fluctuations in ballistic billiards
We study numerically quantum transport through a billiard with a classically
mixed phase space. In particular, we calculate the conductance and Wigner delay
time by employing a recursive Green's function method. We find sharp, isolated
resonances with a broad distribution of resonance widths in both the
conductance and the Wigner time, in contrast to the well-known smooth
conductance fluctuations of completely chaotic billiards. In order to elucidate
the origin of the isolated resonances, we calculate the associated scattering
states as well as the eigenstates of the corresponding closed system. As a
result, we find a one-to-one correspondence between the resonant scattering
states and eigenstates of the closed system. The broad distribution of
resonance widths is traced to the structure of the classical phase space.
Husimi representations of the resonant scattering states show a strong overlap
either with the regular regions in phase space or with the hierarchical parts
surrounding the regular regions. We are thus lead to a classification of the
resonant states into regular and hierarchical, depending on their phase space
portrait.Comment: 2 pages, 5 figures, to be published in J. Phys. Soc. Jpn.,
proceedings Localisation 2002 (Tokyo, Japan
In vitro evidence for senescent multinucleated melanocytes as a source for tumor-initiating cells
Oncogenic signaling in melanocytes results in oncogene-induced senescence (OIS), a stable cell-cycle arrest frequently characterized by a bi- or multinuclear phenotype that is considered as a barrier to cancer progression. However, the long-sustained conviction that senescence is a truly irreversible process has recently been challenged. Still, it is not known whether cells driven into OIS can progress to cancer and thereby pose a potential threat. Here, we show that prolonged expression of the melanoma oncogene N-RAS61K in pigment cells overcomes OIS by triggering the emergence of tumor-initiating mononucleated stem-like cells from senescent cells. This progeny is dedifferentiated, highly proliferative, anoikis-resistant and induces fast growing, metastatic tumors. Our data describe that differentiated cells, which are driven into senescence by an oncogene, use this senescence state as trigger for tumor transformation, giving rise to highly aggressive tumor-initiating cells. These observations provide the first experimental in vitro evidence for the evasion of OIS on the cellular level and ensuing transformation
Variable Anterior Segment Dysgenesis and Cardiac Anomalies Caused by a Novel Truncating Variant of FOXC1
Anterior segment dysgenesis (ASD) encompasses a wide spectrum of developmental abnormalities of the anterior ocular segment, including congenital cataract, iris hypoplasia, aniridia, iridocorneal synechiae, as well as Peters, Axenfeld, and Rieger anomalies. Here, we report a large five-generation Caucasian family exhibiting atypical syndromic ASD segregating with a novel truncating variant of FOXC1. The family history is consistent with highly variable autosomal dominant symptoms including isolated glaucoma, iris hypoplasia, aniridia, cataract, hypothyroidism, and congenital heart anomalies. Whole-exome sequencing revealed a novel variant [c.313_314insA; p.(Tyr105*)] in FOXC1 that disrupts the α-helical region of the DNA-binding forkhead box domain. In vitro studies using a heterologous cell system revealed aberrant cytoplasmic localization of FOXC1 harboring the Tyr105* variant, likely precluding downstream transcription function. Meta-analysis of the literature highlighted the intrafamilial variability related to FOXC1 truncating alleles. This study highlights the clinical variability in ASD and signifies the importance of combining both clinical and molecular analysis approaches to establish a complete diagnosis
Interpretation of photocurrent transients at semiconductor electrodes:Effects of band-edge unpinning
The transient photocurrent response of semiconductor electrodes to chopped illumination often shows spikes and overshoots that are usually interpreted as evidence that surface recombination is occurring. In the case of the high intensities used for light-driven water splitting, the interpretation is less straightforward since the electron transfer reactions are so slow that the minority carrier concentration at or near the surface increases to high values that modify the potential drop across the Helmholtz layer in the electrolyte, leading to ‘band edge unpinning’. In addition, changes in chemical composition of the surface or local changes in pH may also alter the potential distribution across the semiconductor/electrolyte junction. A quantitative theory of band edge unpinning due to minority carrier build up is presented, and numerical calculations of transient photocurrent responses are compared with experimental examples for n-type Fe2O3 and p-type lithium-doped CuO electrodes. It is shown that the apparently high reaction orders (up to third order) with respect to hole concentration reported for hematite photoanodes can be explained as arising from an acceleration of hole transfer by the increased voltage drop across the Helmholtz layer associated with band edge unpinning. The limitations of the band edge unpinning model are discussed considering additional effects associated with modification of the potential distribution brought about by light-induced changes in surface composition, surface dipoles and surface ionic charge.</p
Social Justice, Diversity & Inclusion Keynote: Are We There Yet? Gender Equity in Recovery Settings
Gender equity in recovery settings is the first topic we will tackle. Women represent just over 57% of the undergraduate college population in 2015 and are projected to climb to 58.8% of the total college population by 2024. While not as underrepresented as people of color in collegiate recovery programs (CRPs), women do make up a smaller share of CRP participants at 42.8%. While women are just as likely as men to become develop SUDs, they have lower rates of substance use and SUDs overall, and experience unique obstacles to treatment. Women of color may face additional obstacles and are at greater risk of being subjected to violence. We invite men, women, and transfolk alike to join our feminist recovery panel as we delve into issues of equity and inclusion. While some have deemed feminism, "the other "F" word, we will talk about how feminism benefits everyone. We bring an intersectional lens - realizing that no one shows up or experiences life through one aspect of identity. Our panelists will share from research, personal experience, and program data in order to describe how current societal structures inhibit the opportunities for women to get sober and work a program of recovery and the negative impact on men, collegiate recovery programs, higher education, and society as a whole. Considering an individual, group, and institutional framework for feminism, we hope to inspire attendees to challenge themselves to bring a feminist lens to their work to better create equity and access within collegiate recovery
Review of Evidence For Environmental Causes of Uveal Coloboma
Uveal coloboma is a condition defined by missing ocular tissues and is a significant cause of childhood blindness. It occurs from a failure of the optic fissure to close during embryonic development and may lead to missing parts of the iris, ciliary body, retina, choroid, and optic nerve. Because there is no treatment for coloboma, efforts have focused on prevention. While several genetic causes of coloboma have been identified, little definitive research exists regarding the environmental causes of this condition. We review the current literature on environmental factors associated with coloboma in an effort to guide future research and preventative counseling related to this condition
Coherent Manipulation of Quantum Delta-kicked Dynamics: Faster-than-classical Anomalous Diffusion
Large transporting regular islands are found in the classical phase space of
a modified kicked rotor system in which the kicking potential is reversed after
every two kicks. The corresponding quantum system, for a variety of system
parameters and over long time scales, is shown to display energy absorption
that is significantly faster than that associated with the underlying classical
anomalous diffusion. The results are of interest to both areas of quantum chaos
and quantum control.Comment: 6 pages, 4 figures, to appear in Physical Review
- …