Search for continuous gravitational waves from small-ellipticity sources at low frequencies

We present the results of an all-sky search for continuous gravitational wave signals with frequencies in the 20-500 Hz range from neutron stars with ellipticity of 1e-8. This frequency region is particularly hard to probe because of the quadratic dependence of signal strength on frequency. The search employs the Falcon analysis pipeline on LIGO O2 public data. Compared to previous Falcon analyses the coherence length has been quadrupled, with a corresponding increase in sensitivity. This enables us to search for small ellipticity neutron stars in this low frequency region up to 44 pc away. The frequency derivative range is up to 3e-13 Hz/s easily accommodating sources with ellipticities of 1e-7 and a corresponding factor of 10 increase in reach. New outliers are found, many of which we are unable to associate with any instrumental cause

A frequency resolved atlas of the sky in continuous gravitational waves

We present the first atlas of the continuous gravitational wave sky, produced using LIGO O3a public data. For each 0.045 Hz frequency band and every point on the sky the atlas provides upper limits, signal-to-noise ratios (SNR) and frequencies where the search measures the maximum SNR. The results presented in the atlas are produced with the Falcon pipeline and cover nearly monochromatic gravitational wave signals in the 500-1000 Hz band, with up to +/-5e-11 Hz/s frequency derivative. Compared to the most sensitive results previously published (also produced with the Falcon pipeline) our upper limits are 50% more constraining. Neutron stars with ellipticity of 1e-8 can be detected up to 150 pc away, while allowing for a large fraction of the stars' energy to be lost through non-gravitational channels

The phase transitions in 2D Z(N) vector models for N>4

We investigate both analytically and numerically the renormalization group equations in 2D Z(N) vector models. The position of the critical points of the two phase transitions for N>4 is established and the critical index \nu\ is computed. For N=7, 17 the critical points are located by Monte Carlo simulations and some of the corresponding critical indices are determined. The behavior of the helicity modulus is studied for N=5, 7, 17. Using these and other available Monte Carlo data we discuss the scaling of the critical points with N and some other open theoretical problems.Comment: 19 pages, 8 figures, 10 tables; version to appear on Phys. Rev.

Critical behavior of 3D Z(N) lattice gauge theories at zero temperature

Three-dimensional $Z(N)$ lattice gauge theories at zero temperature are studied for various values of $N$. Using a modified phenomenological renormalization group, we explore the critical behavior of the generalized $Z(N)$ model for $N=2,3,4,5,6,8$. Numerical computations are used to simulate vector models for $N=2,3,4,5,6,8,13,20$ for lattices with linear extension up to $L=96$. We locate the critical points of phase transitions and establish their scaling with $N$. The values of the critical indices indicate that the models with $N>4$ belong to the universality class of the three-dimensional $XY$ model. However, the exponent $\alpha$ derived from the heat capacity is consistent with the Ising universality class. We discuss a possible resolution of this puzzle. We also demonstrate the existence of a rotationally symmetric region within the ordered phase for all $N\geq 5$ at least in the finite volume.Comment: 25 pages, 4 figures, 8 table

Critical behavior of the compact 3d U(1) theory in the limit of zero spatial coupling

Critical properties of the compact three-dimensional U(1) lattice gauge theory are explored at finite temperatures on an asymmetric lattice. For vanishing value of the spatial gauge coupling one obtains an effective two-dimensional spin model which describes the interaction between Polyakov loops. We study numerically the effective spin model for N_t=1,4,8 on lattices with spatial extension ranging from L=64 to L=256. Our results indicate that the finite-temperature U(1) lattice gauge theory belongs to the universality class of the two-dimensional XY model, thus supporting the Svetitsky-Yaffe conjecture.Comment: 17 pages, 5 figures; two references added, a few comments included, title changed; version to appear on J. Stat. Mec

Breast metastasis and lung large-cell neuroendocrine carcinoma: first clinical observation

The lung Large-cell neuroendocrine carcinoma (LCNEC) is a very rare aggressive neuroendocrine tumor with a high propensy to metastasize and very poor prognosis. We report an atypical presentation of lung large-cell neuroendocrine carcinoma was diagnosed from a metastatic nodule on the breast. Our patient is a 59 years-old woman that presented in March 2014 non productive cough. A CT scan showed multiple brain, lung, adrenal gland and liver secondary lesions; moreover, it revealed a breast right nodule near the chest measuring 1.8 cm. The breast nodule and a lung lesions were biopsied and their histology and molecular diagnosis were LCNEC of the lung. To our knowledge, this is the first documented case of breast metastasis from LCNEC of the lung. Furthermore, breast metastasis from extramammary malignancy is uncommon and its diagnosis is difficult but important for proper management and prediction of prognosis. Therefore, a careful clinical history with a thorough clinical examination is needed to make the correct diagnosis. Moreover, metastasis to the breast should be considered in any patient with a known primary malignant tumor history who presents with a breast lump. Anyhow, pathological examination should be performed to differentiate the primary breast cancer from metastatic tumor. Therefore, an accurate diagnosis of breast metastases may not only avoid unnecessary breast resection, more importantly it is crucial to determine an appropriate and systemic treatment

Diffractive jets production in pp-collisions

We consider the exclusive diffractive dissociation of a proton into three jets with large transverse momenta in the double-logarithmic approximation of perturbative QCD. This process is sensitive to the proton unintegrated gluon distribution at small x and to the proton light-cone distribution amplitudes. According to our estimates, an observation of such processes in the early runs at LHC is feasible for jet transverse momenta of the order of 5 GeV.Comment: Presented at International Workshop on Diffraction in High-Energy Physics, La Londe-les-Maures, France, September 9 - 14, 200

Critical behavior of the compact 3d U(1) gauge theory on isotropic lattices

We report on the computation of the critical point of the deconfinement phase transition, critical indices and the string tension in the compact three dimensional U(1) lattice gauge theory at finite temperatures. The critical indices govern the behavior across the deconfinement phase transition in the pure gauge U(1) model and are generally expected to coincide with the critical indices of the two-dimensional XY model. We studied numerically the U(1) model for N_t=8 on lattices with spatial extension ranging from L=32 to L=256. Our determination of the infinite volume critical point on the lattice with N_t=8 differs substantially from the pseudo-critical coupling at L=32, found earlier in the literature and implicitly assumed as the onset value of the deconfined phase. The critical index $\nu$ computed from the scaling of the pseudo-critical couplings with the extension of the spatial lattice agrees well with the XY value $\nu$=1/2. On the other hand, the index $\eta$ shows large deviation from the expected universal value. The possible reasons of such behavior are discussed in details.Comment: 15 pages, 7 figures; version accepted for publication on J. Stat. Mech

Tadalafil modulates aromatase activity and androgen receptor expression in a human osteoblastic cell in vitro model

Purpose Phosphodiesterase type-5 inhibitor (PDE5i) tadalafil administration in men with erectile dysfunction is associated with increased testosterone/estradiol ratio, leading to hypothesize a potential increased effect of androgen action on target tissues. We aimed to characterize, in a cellular model system in vitro, the potential modulation of aromatase and sex steroid hormone receptors upon exposure to tadalafil (TAD). Methods Human osteoblast-like cells SAOS-2 were chosen as an in vitro model system since osteoblasts are target of steroid hormones. Cells were tested for viability upon TAD exposure, which increased cell proliferation. Then, cells were treated with/without TAD for several times to evaluate potential modulation in PDE5, aromatase (ARO), androgen (AR) and estrogen (ER) receptor expression. Results Osteoblasts express significant levels of both PDE5 mRNA and protein. Exposure of cells to increasing concentrations of TAD (10−8–10−7 M) decreased PDE5 mRNA and protein expression. Also, TAD inhibited ARO mRNA and protein expression leading to an increase in testosterone levels in the supernatants. Interestingly, TAD increased total AR mRNA and protein expression and decreased ERα, with an increased ratio of AR/ER, suggesting preferential androgenic vs estrogenic pathway activation. Conclusions Our results demonstrate for the first time that TAD decreases ARO expression and increases AR protein expression in human SAOS-2, strongly suggesting a new control of steroid hormones pathway by PDE5i. These findings might represent the first evidence of translational actions of PDE5i on AR, which leads to hypothesize a growing relevance of this molecule in men with prostate cancer long-term treated with TAD for sexual rehabilitation. Keywords Tadalafil · Osteoblasts · Aromatase · Androgen receptor · Estrogen recepto