Fast transition between Classical and Weak lined T Tauri stars due to external UV dissipation

The discovery of optical jets immersed in the strong UV radiation field of the Rosette Nebula sheds new light on, but meanwhile poses challenges to, the study of externally irradiated jets. The jet systems in the Rosette are found to have a high state of ionization and show unique features. In this paper, we investigate the evolutionary status of the jet driving sources for young solar-like stars. To our surprise, these jet sources indicate unexpected near infrared properties with no excess emission. They are bathed in harsh external UV radiation such that evaporation leads to a fast dissipation of their circumstellar material. This could represent a transient phase of evolution of young solar-like stars between classical and weak lined T Tauri stars. Naked T Tauri stars formed in this way have indistinguishable evolutionary ages from those of classical T Tauri stars resulting from the same episode of star formation. However, it would be hard for such sources to be identified if they are not driving an irradiated jet in a photoionized medium.Comment: 3 figure

Muon spin relaxation study of the magnetism in unilluminated Prussian Blue analogue photomagnets

We present longitudinal field muon spin relaxation ($\mu$SR) measurements in the unilluminated state of the photo-sensitive molecular magnetic Co-Fe Prussian blue analogues M$_{1-2x}$Co$_{1+x}$[Fe(CN)$_6$]$\cdot z$ H$_2$O, where M=K and Rb with $x=0.4$ and $\simeq 0.17$, respectively. These results are compared to those obtained in the $x=0.5$ stoichiometric limit, Co$_{1.5}$[Fe(CN)$_6$]$\cdot 6$ H$_2$O, which is not photo-sensitive. We find evidence for correlation between the range of magnetic ordering and the value of $x$ in the unilluminated state which can be explained using a site percolation model.Comment: 7 pages, 12 figure

One-dimensional structures behind twisted and untwisted superYang-Mills theory

We give a one-dimensional interpretation of the four-dimensional twisted N=1 superYang-Mills theory on a Kaehler manifold by performing an appropriate dimensional reduction. We prove the existence of a 6-generator superalgebra, which does not possess any invariant Lagrangian but contains two different subalgebras that determine the twisted and untwisted formulations of the N=1 superYang-Mills theory.Comment: 12 pages. Final version to appear in Lett. Math. Phys. with improved notation and misprints correcte

Male breast cancer: a disease distinct from female breast cancer

Purpose: Male breast cancer (BC) is rare, representing approximately 1% of cancers that occur in men and approximately 1% of all BCs worldwide. Because male BC is rare, not much is known about the disease, and treatment recommendations are typically extrapolated from data available from clinical trials enrolling female BC patients. Methods: We review the epidemiology, risk factors, prognosis, and the varied molecular and clinicopathologic features that characterize male BC. In addition, we summarize the available data for the use of systemic therapy in the treatment of male BC and explore the ongoing development of targeted therapeutic agents for the treatment of this subgroup of BCs. Results: There are important biological differences between male and female BC. Male BC is almost exclusively hormone receptor positive (+), including the androgen receptor (AR), and is associated with an increased prevalence of BRCA2 germline mutations, especially in men with increased risk for developing high-risk BC. Additional research is warranted to better characterize male BC. To accomplish this, a multi-national consortium approach, such as the International Male Breast Cancer Program, is needed in response to the scarcity of patients. This approach allows the pooling of information from a large number of men with BC and the creation of registries for future therapeutic-focused clinical trials. Conclusions: Given the unique biology of BC in men, promising new therapeutic targets are currently under investigation, including the use of poly-ADP-ribose polymerase inhibitors or AR-targeted agents either as monotherapy or in combination with other agents

Out-of-equilibrium singlet-triplet Kondo effect in a single C_60 quantum dot

We have used an electromigration technique to fabricate a $\rm{C_{{60}}}$ single-molecule transistor (SMT). Besides describing our electromigration procedure, we focus and present an experimental study of a single molecule quantum dot containing an even number of electrons, revealing, for two different samples, a clear out-of-equilibrium Kondo effect. Low temperature magneto-transport studies are provided, which demonstrates a Zeeman splitting of the finite bias anomaly.Comment: 6 pages, 4 figure

Structure Formation, Melting, and the Optical Properties of Gold/DNA Nanocomposites: Effects of Relaxation Time

We present a model for structure formation, melting, and optical properties of gold/DNA nanocomposites. These composites consist of a collection of gold nanoparticles (of radius 50 nm or less) which are bound together by links made up of DNA strands. In our structural model, the nanocomposite forms from a series of Monte Carlo steps, each involving reaction-limited cluster-cluster aggregation (RLCA) followed by dehybridization of the DNA links. These links form with a probability $p_{eff}$ which depends on temperature and particle radius $a$. The final structure depends on the number of monomers (i. e. gold nanoparticles) $N_m$, $T$, and the relaxation time. At low temperature, the model results in an RLCA cluster. But after a long enough relaxation time, the nanocomposite reduces to a compact, non-fractal cluster. We calculate the optical properties of the resulting aggregates using the Discrete Dipole Approximation. Despite the restructuring, the melting transition (as seen in the extinction coefficient at wavelength 520 nm) remains sharp, and the melting temperature $T_M$ increases with increasing $a$ as found in our previous percolation model. However, restructuring increases the corresponding link fraction at melting to a value well above the percolation threshold. Our calculated extinction cross section agrees qualitatively with experiments on gold/DNA composites. It also shows a characteristic ``rebound effect,'' resulting from incomplete relaxation, which has also been seen in some experiments. We discuss briefly how our results relate to a possible sol-gel transition in these aggregates.Comment: 12 pages, 10 figure

Antidepressants have complex associations with longitudinal depressive burden in bipolar disorder

Aims: Antidepressants are common in bipolar disorder (BD), but controversial due to questionable efficacy/tolerability. We assessed baseline antidepressant use/depression associations in BD. Methods: Stanford BD Clinic outpatients, enrolled during 2000\u20132011, assessed with the Systematic Treatment Enhancement Program for BD (STEP-BD) Affective Disorders Evaluation, were monitored up to two years with the STEP-BD Clinical Monitoring Form while receiving naturalistic expert treatment. Prevalence/correlates of baseline antidepressant use in recovered (euthymic 658 weeks)/depressed patients were assessed. Kaplan\u2013Meier survival analyses assessed times to depressive recurrence/recovery in patients with/without baseline antidepressant use, and Cox Proportional Hazard regression analyses assessed covariate effects. Results: Baseline antidepressant use was significantly (albeit without Bonferroni multiple comparison correction) less among 105 recovered (31.4%) versus 153 depressed (44.4%) patients, and among recovered patients (again without Bonferroni correction), associated with Caucasian race, earlier onset, worse Clinical Global Impression scores, and hastened depressive recurrence (only if mood elevation episodes were not censored), driven by lifetime anxiety disorder, and more (even with Bonferroni correction) bipolar II disorder, lifetime anxiety and eating disorders, and core psychotropics. Baseline antidepressant use among depressed patients was associated with significantly (again without Bonferroni correction) older age, female gender, and more (even with Bonferroni correction) anxiolytics/hypnotics, complex pharmacotherapy, and core psychotropics, but no other unfavorable illness characteristic/current mood symptom, and not time to depressive recovery. Limitations: Tertiary BD clinic referral sample receiving open naturalistic expert treatment. Analyses without/with Bonferroni correction. Conclusions: Additional research is required to assess the complex associations between baseline antidepressant use and longitudinal depressive burden in BD

Dirac gaugino as leptophilic dark matter

We investigate the leptophilic properties of Dirac gauginos in an R--symmetric N=2 supersymmetric model with extended gauge and Higgs sectors. The annihilation of Dirac gauginos to leptons requires no chirality flip in the final states so that it is not suppressed as in the Majorana case. This implies that it can be sizable enough to explain the positron excess observed by the PAMELA experiment with moderate or no boost factors. When squark masses are heavy, the annihilation of Dirac gauginos to hadrons is controlled by their Higgsino fraction and is driven by the $hZ$ and $W^+W^-$ final states. Moreover, at variance with the Majorana case, Dirac gauginos with a non-vanishing higgsino fraction can also have a vector coupling with the $Z$ gauge boson leading to a sizable spin--independent scattering cross section off nuclei. Saturating the current antiproton limit, we show that Dirac gauginos can leave a signal in direct detection experiments at the level of the sensitivity of dark matter searches at present and in the near future.Comment: 24 pages, 10 figures, typos corrected, final version published on JCA

Super Yang-Mills Operators from the D3-brane Action in a Curved Background

A consistent truncation of IIB on S^5 has been obtained in the sector of the metric and the 4-form potential. The ansatz contains 20 scalars and all 15 gauge fields of ${\cal N}=8$ gauged supergravity in five dimensions. With this fully non-linear ansatz, the calculations for n-point correlators of super Yang-Mills (SYM) theory via AdS/CFT are simpler than those in the literature that use {\em linear} ansatz followed by non-linear field redefinitions. We work out the SYM operators that couple to the scalars by expanding the Dirac-Born-Infeld (DBI) action plus Wess-Zumino (WZ) terms around an AdS_5\timesS^5 background with the metric fluctuations. The resulting operators agree with those based on a superconformal symmetry argument. We discuss the significance of our results.Comment: one author's name correcte