760 research outputs found
Comparison of Two Trap Net Designs for Sampling Muskellunge
Sampling adequate numbers of muskellunge (Esox masquinongy) is necessary to evaluate stocking success and to collect information on various population metrics (e.g., growth, condition, relative abundance). However, muskellunge are often difficult to sample with standard fish sampling gears. We collected muskellunge in trap nets of two different designs (large trap nets [1.5-m × 1.8-m frames, 1.5-m diameter hoops, double throated, single 1.5-m × 30.5-m lead and 19-mm knotless mesh] and small trap nets [0.9-m × 1.5-m frames, 0.9-m diameter hoops, single throat, single 0.9-m × 15.2-m lead and 19-mm knotted mesh]. We also estimated abundance of muskellunge (\u3e600 mm total length) in three eastern South Dakota waters using marked and recaptured fish collected from the trap net comparisons. Sampling with both large and small trap nets was completed during thespring of 2013 and 2014 soon after ice-out. More muskellunge were collected in large than small trap nets at all three lakes. Mean total lengths of muskellunge did not differ significantly between large and small trap nets; however, length-frequency distribu- tions did differ between net designs. Regardless of trap net design, a small number of muskellunge were collected, likely due to low abundance (population range = 0.10 fish/ha to 0.47 fish/ha) in these populations. Thus, long-term monitoring is necessary to accurately assess populations and associated trends. Sampling with large trap nets during the spring combined with population estimates may improve the ability to monitor and manage muskellunge when compared to sampling with small trap nets
FUSE Observations of Molecular Hydrogen in Translucent Interstellar Clouds: The Line of Sight Toward HD 73882
We report the results of initial FUSE observations of molecular hydrogen (H2)
in translucent clouds. These clouds have greater optical depth than any of the
diffuse clouds previously observed for far-UV H2 absorption, and provide new
insights into the physics and chemistry of such regions. Our initial results
involve observations of HD 73882, a well-studied southern hemisphere star lying
behind substantial interstellar material (E(B-V) = 0.72; A_V = 2.44). We find a
total H2 column density, N(H2) = 1.2 x 10^{21} cm^{-2}, about three times
larger than the values for diffuse clouds previously measured in the far-UV.
The gas kinetic temperature indicated by the ratio N(J=1)/N(J=0) is 58 +/- 10
K. With the aid of ground-based data to calculate an appropriate
multi-component curve of growth, we have determined column densities for all
rotational levels up to J = 7. The J >= 2 states can be reasonably fitted with
a rotational excitation temperature of 307 +/- 23 K. Both the kinetic and
rotational temperatures are similar to those found in previous investigations
of diffuse clouds. The ratios of carbonaceous molecules to hydrogen molecules
are also similar to ratios in diffuse clouds, suggesting a similar chemistry
for this line of sight.Comment: 7 pages, 3 figures, to appear in ApJ Letters (FUSE first-results
issue
Intermediate scale structure of the interstellar medium towards NGC 6231 in Sco OB1 with FUSE
The FUSE far-ultraviolet interstellar spectra toward seven targets in NGC
6231 show that the molecules H_2, HD, and CO as well as various atomic species
are distributed in several clouds. The main absorption component found on the
sight lines lies in the Lupus cloud region at a distance of about 150 pc, and
there is a weaker second one, presumably in the Sco OB1 shell surrounding NGC
6231 (d~1.8 kpc). H_2 excitation modelling is used to constrain the radiation
field and the density in the gas; HD is used to estimate the abundance of H+.
The small angular separation of the target stars allows column density
variations to be probed over the field of view, on scales of 0.05 pc in the
case of the Lupus cloud distance. They are 40% for H_2 and 60% for H I. A
rather strong radiation field inside the molecular clouds suggests a separation
of the gas into smaller cloudlets also along the line of sight.Comment: 12 pages, accepted for publication in Astronomy & Astrophysic
Magnetocrystalline Anisotropy Energy of Transition Metal Thin Films: A Non-perturbative Theory
The magnetocrystalline anisotropy energy E(anis) of free-standing monolayers
and thin films of Fe and Ni is determined using two different semi-empirical
schemes. Within a tight-binding calculation for the 3d bands alone, we analyze
in detail the relation between bandstructure and E(anis), treating spin-orbit
coupling non-pertubatively. We find important contributions to E(anis) due to
the lifting of band degeneracies near the Fermi level by SOC. The important
role of degeneracies is supported by the calculation of the electron
temperature dependence of the magnetocrystalline anisotropy energy, which
decreases with the temperature increasing on a scale of several hundred K. In
general, E(anis) scales with the square of the SOC constant. Including 4s bands
and s-d hybridization, the combined interpolation scheme yields anisotropy
energies that quantitatively agree well with experiments for Fe and Ni
monolayers on Cu(001). Finally, the anisotropy energy is calculated for systems
of up to 14 layers. Even after including s-bands and for multilayers, the
importance of degeneracies persists. Considering a fixed fct-Fe structure, we
find a reorientation of the magnetization from perpendicular to in-plane at
about 4 layers. For Ni, we find the correct in-plane easy-axis for the
monolayer. However, since the anisotropy energy remains nearly constant, we do
not find the experimentally observed reorientation.Comment: 15 pages, Revtex, 15 postscript figure
Long-term responders to trastuzumab monotherapy in first-line HER-2+ advanced breast cancer: characteristics and survival data.
The impact of HER2-targeted therapy alone followed by the addition of chemotherapy at disease progression (PD) versus upfront combination was investigated by the SAKK 22/99 trial. The aim of this exploratory analysis of the SAKK 22/99 trial was to characterize the specific subset of patients deriving long-term benefit from trastuzumab monotherapy alone and to identify potential predictive factors of long-term response.
This is an unplanned post-hoc analysis of patients randomized to Arm A (trastuzumab monotherapy). Patients were divided in two groups: patients with durable clinical benefit from trastuzumab monotherapy and short-term responders without durable clinical benefit from trastuzumab monotherapy Univariate and multivariate analyses of clinical characteristics correlating with response duration was performed.
Eighty six patients were randomized in arm A, 24 patients (28%) were long-term responders and 62 (72%) were short-term responders with a 5y-overall survival (OS) of 54% (95% CI 31-72) and of 18% (95%CI 10-30), respectively. Absence of ER expression, absence of PgR expression and presence of visceral disease emerged as possible negative predictive factors for durable clinical benefit.
Durable clinical benefit can be achieved with trastuzumab monotherapy in a subgroup of HER2-positive patients with advanced disease and it is predictive for longer OS. Further investigations of predictive biomarkers are necessary to better characterize this subgroup of patients and develop further de-escalating strategies.
NCT00004935 ; first posted 27.01.2003, retrospectively registered
First-line temozolomide combined with bevacizumab in metastatic melanoma: a multicentre phase II trial (SAKK 50/07)
Background: Oral temozolomide has shown similar efficacy to dacarbazine in phase III trials with median progression-free survival (PFS) of 2.1 months. Bevacizumab has an inhibitory effect on the proliferation of melanoma and sprouting endothelial cells. We evaluated the addition of bevacizumab to temozolomide to improve efficacy in stage IV melanoma. Patients and methods: Previously untreated metastatic melanoma patients with Eastern Cooperative Oncology Group performance status of two or more were treated with temozolomide 150 mg/m2 days 1-7 orally and bevacizumab 10 mg/kg body weight i.v. day 1 every 2 weeks until disease progression or unacceptable toxicity. The primary end point was disease stabilisation rate [complete response (CR), partial response (PR) or stable disease (SD)] at week 12 (DSR12); secondary end points were best overall response, PFS, overall survival (OS) and adverse events. Results: Sixty-two patients (median age 59 years) enrolled at nine Swiss centres. DSR12 was 52% (PR: 10 patients and SD: 22 patients). Confirmed overall response rate was 16.1% (CR: 1 patient and PR: 9 patients). Median PFS and OS were 4.2 and 9.6 months. OS (12.0 versus 9.2 months; P = 0.014) was higher in BRAF V600E wild-type patients. Conclusions: The primary end point was surpassed showing promising activity of this bevacizumab/temozolomide combination with a favourable toxicity profile. Response and OS were significantly higher in BRAF wild-type patient
Schwinger boson theory of anisotropic ferromagnetic ultrathin films
Ferromagnetic thin films with magnetic single-ion anisotropies are studied
within the framework of Schwinger bosonization of a quantum Heisenberg model.
Two alternative bosonizations are discussed. We show that qualitatively correct
results are obtained even at the mean-field level of the theory, similar to
Schwinger boson results for other magnetic systems. In particular, the
Mermin-Wagner theorem is satisfied: a spontaneous magnetization at finite
temperatures is not found if the ground state of the anisotropic system
exhibits a continuous degeneracy. We calculate the magnetization and effective
anisotropies as functions of exchange interaction, magnetic anisotropies,
external magnetic field, and temperature for arbitrary values of the spin
quantum number. Magnetic reorientation transitions and effective anisotropies
are discussed. The results obtained by Schwinger boson mean-field theory are
compared with the many-body Green's function technique.Comment: 14 pages, including 7 EPS figures, minor changes, final version as
publishe
Comfort radicalism and NEETs: a conservative praxis
Young people who are not in education, employment or training (NEET) are construed by policy makers as a pressing problem about which something should be done. Such young people's lack of employment is thought to pose difficulties for wider society in relation to social cohesion and inclusion and it is feared that they will become a 'lost generation'. This paper(1) draws upon English research, seeking to historicise the debate whilst acknowledging that these issues have a much wider purchase. The notion of NEETs rests alongside longstanding concerns of the English state and middle classes, addressing unruly male working class youth as well as the moral turpitude of working class girls. Waged labour and domesticity are seen as a means to integrate such groups into society thereby generating social cohesion. The paper places the debate within it socio-economic context and draws on theorisations of cognitive capitalism, Italian workerism, as well as emerging theories of antiwork to analyse these. It concludes by arguing that ‘radical’ approaches to NEETs that point towards inequities embedded in the social structure and call for social democratic solutions veer towards a form of comfort radicalism. Such approaches leave in place the dominance of capitalist relations as well as productivist orientations that celebrate waged labour
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