Power calculation for gravitational radiation: oversimplification and the importance of time scale

A simplified formula for gravitational-radiation power is examined. It is shown to give completely erroneous answers in three situations, making it useless even for rough estimates. It is emphasized that short timescales, as well as fast speeds, make classical approximations to relativistic calculations untenable.Comment: Three pages, no figures, accepted for publication in Astronomische Nachrichte

Quality traits of Procambarus clarkii (girard) related to sex and refrigerated storage

The red swamp crayfish (Procambarus clarkii, Girard) is the most widespread alien species in Europe. Imported from Louisiana to southern Spain in 1973, where at present it is reared in crayfish farm and also diffused in the wild, it was introduced into Italy in the '80s and is now well established in natural environments of northern and central Italy. Naturalization of this alien species poses risks for aquatic ecosystems and its use as food may be a way to limit its spreading. The aim of this study was to analyse the morphological, mercantile and biochemical characteristics of male and female specimens of Procambarus clarkii and to evaluate changes in qualitative traits during refrigerated storage. Specimens of red swamp crayfish collected in a river, after a rearing period of 85 days in tanks, were harvested, killed by hypothermia and refrigerated (1°C). Male (n=31) and female (n=26) specimens were separated and measured for total body and abdomen length, 1 (n=10), 3 (n=16), 8 (n=16) and 10 days (n=15) after harvesting. They were weighed, sectioned to separate claws and tails (shell-on), which were weighed individually and their colour parameters (lightness, L*; chromaticity indexes, a* and b*) measured in dorsal and ventral sites. A pooled sample consisting of tail muscle of 2-3 specimens having the same storage times was homogenized and analysed for total lipids, qualitative and quantitative fatty acid composition and malondialdehyde (MDA). The other tails (shell-on) were steamed, the exoskeleton removed and abdominal muscles (shell-off tails) analysed for colour parameters in dorsal and ventral sites, and for free water (by compression method). Data was analysed by GLM using the SAS Package, with sex, storage time and relative interaction (except for data of chemical analysis) as fixed effects. Females and males differed in total (p<0.05) and abdominal (p<0.01) length (8.65 vs 8.27cm and 4.32 vs 4.04cm, respectively) and in body weight (corrected for cheliped weight, due their lack in some cases; 16.35 vs 13.89g; p<0.05), however the cooked-meat yield of shell-on tails was similar (46.53 vs 42.93%; p=0.19). Regarding colour parameters, the two sexes only differed in L*, which was significantly greater in males in the different sites of measurement, except the ventral site of raw shell-on tails. Males and females showed a similar water holding capacity of abdominal meat (mean 10.78±6.33cm2). No differences between the sexes were recorded for total lipids (mean 1.05±0.14%), MDA content and fatty acid profile (means SFA: 22.16%, MUFA: 28.40%, PUFAn6: 20.39%; PUFAn3: 28.80%; EPA: 18.24%; DHA: 7.17%). During refrigerated storage, a significant decrease in water holding capacity of muscle (free water increasing from 14.07 to 26.15cm2 on days 1 and 10, respectively; p<0.001) and in cooked-meat yield (from 50.92 to 39.11% on days 1 and 10, respectively; p<0.01) and sharp changes in cooked tail muscle colour parameters were noticed. The latter body part showed a significant decrease (p<0.001) in a* and b* at the dorsal site and in L* at the ventral site (77.74 and 49.14 on days 1 and 10, respectively) with increasing storage. During the refrigerated storage of the whole crayfish the changes recorded for the examined parameters indicate the quality decay, particularly after the 3rd day

Lower bounds on the blow-up rate of the axisymmetric Navier-Stokes equations II

Consider axisymmetric strong solutions of the incompressible Navier-Stokes equations in $\R^3$ with non-trivial swirl. Let $z$ denote the axis of symmetry and $r$ measure the distance to the z-axis. Suppose the solution satisfies either $|v (x,t)| \le C_*{|t|^{-1/2}}$ or, for some \e > 0, $|v (x,t)| \le C_* r^{-1+\epsilon} |t|^{-\epsilon /2}$ for $-T_0\le t < 0$ and $0<C_*<\infty$ allowed to be large. We prove that $v$ is regular at time zero.Comment: More explanations and a new appendi

Ultrafast control of Rabi oscillations in a polariton condensate

We report the experimental observation and control of space and time-resolved light-matter Rabi oscillations in a microcavity. Our setup precision and the system coherence are so high that coherent control can be implemented with amplification or switching off of the oscillations and even erasing of the polariton density by optical pulses. The data is reproduced by a fundamental quantum optical model with excellent accuracy, providing new insights on the key components that rule the polariton dynamics.Comment: 5 pages, 3 figures, supplementary 7 pages, 4 figures. Supplementary videos: https://drive.google.com/folderview?id=0B0QCllnLqdyBNjlMLTdjZlNhbTQ&usp=sharin

The colored Hanbury Brown--Twiss effect

The Hanbury Brown--Twiss effect is one of the celebrated phenomenologies of modern physics that accommodates equally well classical (interferences of waves) and quantum (correlations between indistinguishable particles) interpretations. The effect was discovered in the late thirties with a basic observation of Hanbury Brown that radio-pulses from two distinct antennas generate signals on the oscilloscope that wiggle similarly to the naked eye. When Hanbury Brown and his mathematician colleague Twiss took the obvious step to propose bringing the effect in the optical range, they met with considerable opposition as single-photon interferences were deemed impossible. The Hanbury Brown--Twiss effect is nowadays universally accepted and, being so fundamental, embodies many subtleties of our understanding of the wave/particle dual nature of light. Thanks to a novel experimental technique, we report here a generalized version of the Hanbury Brown--Twiss effect to include the frequency of the detected light, or, from the particle point of view, the energy of the detected photons. In addition to the known tendencies of indistinguishable photons to arrive together on the detector, we find that photons of different colors present the opposite characteristic of avoiding each others. We postulate that fermions can be similarly brought to exhibit positive (boson-like) correlations by frequency filtering.Comment: 18 pages, includes supplementary material of the derivation

Real-world efficacy and safety of nivolumab in previously-treated metastatic renal cell carcinoma, and association between immune-related adverse events and survival: the Italian expanded access program

Background: The Italian Renal Cell Cancer Early Access Program was an expanded access program that allowed access to nivolumab, for patients (pts) with metastatic renal cell carcinoma (mRCC) prior to regulatory approval. Methods: Pts with previously treated advanced or mRCC were eligible to receive nivolumab 3 mg/kg every 2 weeks. Pts included in the analysis had received ≥1 dose of nivolumab and were monitored for drug-related adverse events (drAEs) using CTCAE v.4.0. Immune-related (ir) AEs were defined as AEs displaying a certain, likely or possible correlation with immunotherapy (cutaneous, endocrine, hepatic, gastro-intestinal and pulmonary). The association between overall survival (OS) and irAEs was assessed, and associations between variables were evaluated with a logistic regression model. Results: A total of 389 pts were enrolled between July 2015 and April 2016. Overall, the objective response rate was 23.1%. At a median follow-up of 12 months, the median progression-free survival was 4.5 months (95% CI 3.7-6.2) and the 12-month overall survival rate was 63%. Any grade and grade 3-4 drAEs were reported in 124 (32%) and 27 (7%) of pts, respectively, and there were no treatment-related deaths. Any grade irAEs occurred in 76 (20%) of patients, 8% cutaneous, 4% endocrine, 2% hepatic, 5% gastro-intestinal and 1% pulmonary. Of the 22 drAEs inducing treatment discontinuation, 10 (45%) were irAEs. Pts with drAEs had a significantly longer survival than those without drAEs (median OS 22.5 versus 16.4 months, p = 0.01). Pts with irAEs versus without irAEs had a more significant survival benefit (median OS not reached versus 16.8 months, p = 0.002), confirmed at the landmark analysis at 6 weeks. The occurrence of irAEs displayed a strong association with OS in univariable (HR 0.48, p = 0.003) and multivariable (HR 0.57, p = 0.02) analysis. Conclusions: The appearance of irAEs strongly correlates with survival benefit in a real-life population of mRCC pts treated with nivolumab

The FXR agonist obeticholic acid inhibits the cancerogenic potential of human cholangiocarcinoma

Cholangiocarcinoma (CCA) is an aggressive cancer with high resistance to chemotherapeutics. CCA is enriched in cancer stem cells, which correlate with aggressiveness and prognosis. FXR, a member of the metabolic nuclear receptor family, is markedly down-regulated in human CCA. Our aim was to evaluate, in primary cultures of human intrahepatic CCA (iCCA), the effects of the FXR agonist obeticholic acid (OCA), a semisynthetic bile acid derivative, on their cancerogenic potential. Primary human iCCA cell cultures were prepared from surgical specimens of mucinous or mixed iCCA subtypes. Increasing concentrations (0–2.5 μM) of OCA were added to culture media and, after 3–10 days, effects on proliferation (MTS assay, cell population doubling time), apoptosis (annexin V-FITC/propidium iodide), cell migration and invasion (wound healing response and Matrigel invasion assay), and cancerogenic potential (spheroid formation, clonogenic assay, colony formation capacity) were evaluated. Results: FXR gene expression was downregulated (RT-qPCR) in iCCA cells vs normal human biliary tree stem cells (p < 0.05) and in mucinous iCCA vs mixed iCCA cells (p < 0.05) but was upregulated by addition of OCA. OCA significantly (p < 0.05) inhibited proliferation of both mucinous and mixed iCCA cells, starting at a concentration as low as 0.05 μM. Also, CDCA (but not UDCA) inhibited cell proliferation, although to a much lower extent than OCA, consistent with its different affinity for FXR. OCA significantly induced apoptosis of both iCCA subtypes and decreased their in vitro cancerogenic potential, as evaluated by impairment of colony and spheroid formation capacity and delayed wound healing and Matrigel invasion. In general, these effects were more evident in mixed than mucinous iCCA cells. When tested together with Gemcitabine and Cisplatin, OCA potentiated the anti-proliferative and pro-apoptotic effects of these chemotherapeutics, but mainly in mixed iCCA cells. OCA abolished the capacity of both mucinous and mixed iCCA cells to form colonies when administered together with Gemcitabine and Cisplatin. In subcutaneous xenografts of mixed iCCA cells, OCA alone or combined with Gemcitabine or Cisplatin markedly reduced the tumor size after 5 weeks of treatment by inducing necrosis of tumor mass and inhibiting cell proliferation. In conclusion, FXR is down-regulated in iCCA cells, and its activation by OCA results in anti-cancerogenic effects against mucinous and mixed iCCA cells, both in vitro and in vivo. The effects of OCA predominated in mixed iCCA cells, consistent with the lower aggressiveness and the higher FXR expression in this CCA subtype. These results, showing the FXR-mediated capacity of OCA to inhibit cholangiocarcinogenesis, represent the basis for testing OCA in clinical trials of CCA patients

On weak convergence of locally periodic functions

We prove a generalization of the fact that periodic functions converge weakly to the mean value as the oscillation increases. Some convergence questions connected to locally periodic nonlinear boundary value problems are also considered.Comment: arxiv version is already officia