X-ray pulsations from the radio-quiet gamma-ray pulsar in CTA 1

Prompted by the Fermi LAT discovery of a radio-quiet gamma-ray pulsar inside the CTA 1 supernova remnant, we obtained a 130 ks XMM-Newton observation to assess the timing behavior of this pulsar. Exploiting both the unprecedented photon harvest and the contemporary Fermi LAT timing measurements, a 4.7 sigma single peak pulsation is detected, making PSR J0007+7303 the second example, after Geminga, of a radio-quiet gamma-ray pulsar also seen to pulsate in X-rays. Phase-resolved spectroscopy shows that the off-pulse portion of the light curve is dominated by a power-law, non-thermal spectrum, while the X-ray peak emission appears to be mainly of thermal origin, probably from a polar cap heated by magnetospheric return currents, pointing to a hot spot varying throughout the pulsar rotation.Comment: 19 pages, 4 figures. Accepted for publication in ApJ Letter

Evidence Evaluation: Measure Z Corresponds to Human Utility Judgments Better than Measure L and Optimal-Experimental-Design Models

Evidence evaluation is a crucial process in many human activities, spanning from medical diagnosis to impression formation. The present experiments investigated which, if any, normative model best conforms to people’s intuition about the value of the obtained evidence. Psychologists, epistemologists, and philosophers of science have proposed several models to account for people’s intuition about the utility of the obtained evidence with respect either to a focal hypothesis or to a constellation of hypotheses. We pitted against each other the so called optimal-experimental-design models (i.e., Bayesian diagnosticity, log10 diagnosticity, information gain, Kullback-Leibler distance, probability gain, and impact) and measures L and Z to compare their ability to describe humans’ intuition about the value of the obtained evidence. Participants received words-and-numbers scenarios concerning two hypotheses and binary features. They were asked to evaluate the utility of “yes” and “no” answers to questions about some features possessed in different proportions (i.e., the likelihoods) by two types of extraterrestrial creatures (corresponding to two mutually exclusive and exhaustive hypotheses). Participants evaluated either how an answer was helpful or how an answer decreased/increased their beliefs with respect either to a single hypothesis or to both hypotheses. We fitted mixed-effects models and we used the Akaike information criterion (AIC) and the Bayesian information criterion (BIC) values to compare the competing models of the value of the obtained evidence. Overall, the experiments showed that measure Z was the best-fitting model of participants’ judgments of the value of obtained answers. We discussed the implications for the human hypothesis-evaluation process

Flow cytometry for feline lymphoma : a retrospective study regarding pre-analytical factors possibly affecting the quality of samples

Objectives: Flow cytometry (FC) is becoming increasingly popular among veterinary oncologists for the diagnosis of lymphoma or leukaemia. It is accurate, fast and minimally invasive. Several studies of FC have been carried out in canine oncology and applied with great results, whereas there is limited knowledge and use of this technique in feline patients. This is mainly owing to the high prevalence of intra-abdominal lymphomas in this species and the difficulty associated with the diagnostic procedures needed to collect the sample. The purpose of the present study is to investigate whether any pre-analytical factor might affect the quality of suspected feline lymphoma samples for FC analysis. Methods: Ninety-seven consecutive samples of suspected feline lymphoma were retrospectively selected from the authors\u2019 institution\u2019s FC database. The referring veterinarians were contacted and interviewed about several different variables, including signalment, appearance of the lesion, features of the sampling procedure and the experience of veterinarians performing the sampling. Statistical analyses were performed to assess the possible influence of these variables on the cellularity of the samples and the likelihood of it being finally processed for FC. Results: Sample cellularity is a major factor in the likelihood of the sample being processed. Moreover, sample cellularity was significantly influenced by the needle size, with 21 G needles providing the highest cellularity. Notably, the sample cellularity and the likelihood of being processed did not vary between peripheral and intra-abdominal lesions. Approximately half of the cats required pharmacological restraint. Side effects were reported in one case only (transient swelling after peripheral lymph node sampling). Conclusions and relevance: FC can be safely applied to cases of suspected feline lymphomas, including intra-abdominal lesions. A 21 G needle should be preferred for sampling. This study provides the basis for the increased use of this minimally invasive, fast and cost-effective technique in feline medicine

Genetic characterization of four native Italian shepherd dog breeds and analysis of their relationship to cosmopolitan dog breeds using microsatellite markers

Very little research into genetic diversity of Italian native dog breeds has been carried out so far. In this study we aimed to estimate and compare the genetic diversity of four native Italian shepherd dog breeds: the Maremma, Bergamasco, Lupino del Gigante and Oropa shepherds. Therefore, some cosmopolitan dog breeds, which have been widely raised in Italy for a long time past, have also been considered to check possible influence of these dog populations on the Italian autochthonous breeds considered here. A total of 212 individuals, belonging to 10 different dog breeds, were sampled and genotyped using 18 autosomal microsatellite loci. We analyzed the genetic diversity of these breeds, within breed diversity, breed relationship and population structure. The 10 breeds considered in this study were clearly genetically differentiated from each other, regardless of current population sizes and the onset of separate breeding history. The level of genetic diversity explained 20% of the total genetic variation. The level of H E found here is in agreement with that found by other studies. The native Italian breeds showed generally higher genetic diversity compared with the long established, well-defined cosmopolitan dog breeds. As the Border Collie seems closer to the Italian breeds than the other cosmopolitan shepherd dogs considered here, a possible utilization of this breed to improve working performance in Italian traditional working shepherd dogs cannot be ignored. The data and information found here can be utilized in the organization of conservation programs planned to reduce inbreeding and to minimize loss of genetic variability

Gonadotropin-releasing hormone agonists reduce the migratory and the invasive behavior of androgen-independent prostate cancer cells by interfering with the activity of IGF-I

Androgen-independent prostate carcinoma is characterized by a high proliferation rate and by a strong metastatic behavior. We have previously shown that GnRH agonists exert a direct and specific inhibitory action on the proliferation of androgen-independent prostate cancer cells (DU 145). These compounds mainly act by interfering with the mitogenic activity of growth factors, such as the insulin-like growth factor-I (IGF-I). The present experiments were performed to clarify whether GnRH agonists might also affect the migratory and the invasive behavior of androgen-independent prostate cancer cells and to define their mechanism of action. First we showed that the GnRH agonist Leuprolide reduces the migration of DU 145 cells towards a chemoattractant and their ability to invade a reconstituted basement membrane. Experiments were then performed to clarify whether the GnRH agonist might act by interfering with the pro-metastatic activity of IGF-I. We found that, in androgen-independent prostate cancer cells, Leuprolide: a) interferes with the IGF-I system (receptor protein expression and tyrosine-phosphorylation); b) abrogates the IGF-I-induced phosphorylation of Akt (a kinase previously shown by us to mediate the pro-metastatic activity of IGF-I in prostate cancer cells); c) counteracts the migration and the invasive activity of the cells stimulated by IGF-I; d) abolishes the effects of IGF-I on cell morphology, on actin cytoskeleton organization and on alpha v beta 3 integrin expression/cellular localization. These data indicate that GnRH agonists, in addition to their well known antiproliferative effect, can also exert a significant inhibitory activity on the migratory and invasive behavior of androgen- independent prostate cancer cells, expressing the GnRH receptor. GnRH agonists act by interfering with the pro-metastatic activity of the growth factor IGF-I