520 research outputs found
Bright low mass eclipsing binary candidates observed by STEREO
Observations from the Heliospheric Imagers (HI-1) on both the STEREO
spacecraft have been analysed to search for bright low mass eclipsing binaries
(EBs) and potential brown dwarf transits and to determine the radii of the
companions. A total of 9 EB candidates have been found, ranging in brightness
from V=6.59 mag to V=11.3 mag, where the radius of the companion appears to be
less than 0.4 Rsol, with a diverse range of host temperatures, from 4074 K to
6925 K. Both components of one candidate, BD-07 3648, appear to be less than
0.4 Rsol and this represents a particularly interesting system for further
study. The shapes of the eclipses in some cases are not clear enough to be
certain they are total and the corresponding radii found should therefore be
considered as lower limits. The EBs reported in this paper have either been
newly found by the present analysis, or previously reported to be eclipsing by
our earlier STEREO/HI-1 results. One of the new objects has subsequently been
confirmed using archival SuperWASP data. This study was made possible by using
an improved matched filter extraction algorithm, which is described in this
paper.Comment: 11 pages, 6 figures, 2 tables, accepted for publication in MNRA
Convergence towards a European strategic culture? A constructivist framework for explaining changing norms.
The article contributes to the debate about the emergence of a European strategic culture to underpin a European Security and Defence Policy. Noting both conceptual and empirical weaknesses in the literature, the article disaggregates the concept of strategic culture and focuses on four types of norms concerning the means and ends for the use of force. The study argues that national strategic cultures are less resistant to change than commonly thought and that they have been subject to three types of learning pressures since 1989: changing threat perceptions, institutional socialization, and mediatized crisis learning. The combined effect of these mechanisms would be a process of convergence with regard to strategic norms prevalent in current EU countries. If the outlined hypotheses can be substantiated by further research the implications for ESDP are positive, especially if the EU acts cautiously in those cases which involve norms that are not yet sufficiently shared across countries
Home schooling during the COVID-19 pandemic in the United Kingdom : the experience of families of children with neurodevelopmental conditions
The COVID-19 outbreak, and associated school restrictions affected the learning experience of students worldwide. The current study focused on the learning experiences of United Kingdom children with neurodevelopmental conditions, including autism and/or intellectual disability. Specifically, the aim was to examine families’ experience with school support for home schooling, families’ resources, and level of satisfaction with schools among families whose children engaged with home schooling, hybrid learning, and school-based learning during the pandemic. An online survey took place in 2021, approximately 1 year since the start of the COVID-19 pandemic in the United Kingdom. Participants were recruited mostly through social media with support via several charities across the United Kingdom. Participants were 809 parents/carers of children with autism and/or intellectual disability aged 5 – 15 years. Of these, 59% were learning from home daily during home schooling, 19% spent some days in school (hybrid learning), and 22% were going to school daily during school restrictions. Parents/carers reported on the support received from schools, the resources accessed, and the resources needed but not accessed to facilitate learning. They also reported on their level of satisfaction with school support and school management of COVID-19 risks. Results indicated that learning during the COVID-19 pandemic was mostly via school-provided worksheets, in the home and hybrid learning group. Families had access to the internet/data and a laptop, computer, or tablet to facilitate learning. However, in both learning groups (i.e., home and hybrid learning) they needed but did not have access to special equipment, special software, and a printer. Importantly, 11% of families in home and hybrid learning groups reported not having access to a desk/table. Satisfaction with school support was low in the home and hybrid learning groups. Satisfaction with COVID-19 management was higher for families of children attending school daily (i.e., the school-based learning group). Future education policy decisions during public health crises should take into consideration the needs of children with neurodevelopmental conditions including autism and/or intellectual disability
Response and Acquired Resistance to Everolimus in Anaplastic Thyroid Cancer
Everolimus, an inhibitor of the mammalian target of rapamycin (mTOR), is effective in treating tumors harboring alterations in the mTOR pathway. Mechanisms of resistance to everolimus remain undefined. Resistance developed in a patient with metastatic anaplastic thyroid carcinoma after an extraordinary 18-month response. Whole-exome sequencing of pretreatment and drug-resistant tumors revealed a nonsense mutation in TSC2, a negative regulator of mTOR, suggesting a mechanism for exquisite sensitivity to everolimus. The resistant tumor also harbored a mutation in MTOR that confers resistance to allosteric mTOR inhibition. The mutation remains sensitive to mTOR kinase inhibitors
Observation of Two Narrow States Decaying into and
We report the first observation of two narrow charmed strange baryons
decaying to and , respectively, using data from
the CLEO II detector at CESR. We interpret the observed signals as the
and , the symmetric partners
of the well-established antisymmetric and .
The mass differences and
are measured to be and
, respectively.Comment: 11 pages, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Cooperative Extension Work in Aroostook County, Maine, Annual Report, December 1, 1966-November 30, 1967
Further Search for the Two-Photon Production of the Glueball Candidate
The CLEOII detector at the Cornell e+ e- storage ring CESR has been used to
search for the two-photon production of the decaying into pi+ pi-.
No evidence for a signal is found in data corresponding to an integrated
luminosity of 4.77/fb and a 95% CL upper limit on of 2.5 eV is set. If this result is combined with the BES Collaboration's
measurement of in radiative decay, a 95% CL
lower limit on the stickiness of the of 73 is obtained. If the
recent CLEO result for \Gamma_{two-photon} * BR{\K_S K_S} is combined with
the present result, the stickiness of the is found to be larger
than 102 at the 95% CL. These results for the stickiness (the ratio of the
probabilities for two-gluon coupling and two-photon coupling) provide further
support for a substantial neutral parton content in the .Comment: 8 pages, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Study of 3-prong Hadronic Decays with Charged Kaons
Using a sample of 4.7/fb integrated luminosity accumulated with the CLEO-II
detector at the Cornell Electron Storage Ring (CESR), we have measured the
branching fractions of the tau lepton into and relative to and relative to . The relative branching fractions are: (5.16+-0.20+-0.50)*,
(1.52+-0.14+-0.29)*, (2.54+-0.44+-0.39)* and at 95%
C.L., respectively. Coupled with additional experimental information, we use
our results to extract information on the structure of three-prong tau decays
to charged kaons.Comment: 16 pages postscript file also available through
http://w4.lns.cornell.edu/public/CLN
First Observation of
We report on a study of exclusive radiative decays of the Upsilon(1S)
resonance collected with the CLEO-II detector operating at CESR. We present the
first observation of the radiative decays Upsilon(1S)->gamma pi+pi- and
Upsilon(1S)->gamma pi0pi0. For the dipion mass regime m(pipi)>1.0 GeV, we
obtain Br(Upsilon(1S)->gamma pi+pi-=(6.3+/-1.2+/-1.3) x 10^(-5), and
Br(Upsilon(1S)->gamma pi0pi0=(1.7+/-0.6+/-0.3) x 10^(-5). The observed gamma
pipi events are consistent with the hypothesis Upsilon(1S)->gamma f2(1270).Comment: 9 pages, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
Flavor-Specific Inclusive B Decays to Charm
We have measured the branching fractions for B -> D_bar X, B -> D X, and B ->
D_bar X \ell^+ \nu, where ``B'' is an average over B^0 and B^+, ``D'' is a sum
over D^0 and D^+, and``D_bar'' is a sum over D^0_bar and D^-. From these
results and some previously measured branching fractions, we obtain Br(b -> c
c_bar s) = (21.9 3.7)%, Br(b -> s g) K^-
\pi^+) = (3.69 0.20)%. Implications for the ``B semileptonic decay
problem'' (measured branching fraction being below theoretical expectations)
are discussed. The increase in the value of Br(b -> c c_bar s) due to eliminates 40% of the discrepancy.Comment: 12 page postscript file, postscript file also available through
http://w4.lns.cornell.edu/public/CLN
- …