Qualche considerazione sulla costante di correlazione tra il lungo computo Maya ed il calendario occidentale

The remains of the Mayan civilization describe (among other things) many observations of various astronomical phenomena observed by the Maya. The modern Celestial Mechanics allows us to calculate with great accuracy when astronomical phenomena occurred and were visible in the sky for a given location on Earth too far back in time. The Maya developed the very accurate calendar known as the Long Count, but when we want to synchronize it with the western one, the correlation between the two is surprisingly very uncertain. The two calendars can be connected each other by analyzing historical data and various astronomical phenomena of which we have a paper trail in the ancient texts that is sufficient to establish an appropriate chronology. The correlation between the Long Count and the Gregorian calendar has been studied by many authors who have obtained correlation values very different from each other (almost 50 different values), which differ from one another by hundreds of years, producing considerable uncertainty in Mayan history in relation to other civilizations. Astronomy can potentially solve the problem of the correct identification of the relationship, provided that the records are available from the observations performed and documented chronologically according to the Mayan Long Count. In the present work has been performed the statistical analysis of the 52 correlations at present known and used pointing out that at the present state of knowledge it is not possible to get the exact determination of the coefficient of synchronization (correlation) between the Long Count and the Western calendar, but only an assessment of its probability distribution function, thus allowing you to assign a probability value to each value of the correlation that has been published. The statistical analysis of the 52 values at present known leads to an optimal value of the correlation constant of JDN 588159 with an uncertainty of about ±35 years

A method for dating archaeological structures based on astronomical alignments

A method for dating archaeological structures, based on their astronomical alignments, is presented. In this method, the number of alignments falling within a tolerance band is calculated in suitable time bins. These data are then converted into the probability for the alignments to be random. The time corresponding to the center of the (inverted) probability peak is taken as the structure dating, to which a confidence interval is attributed. Through the analysis of an elliptical enclosure in the Bergamo province (Lombardy, Northern Italy), more details of which were provided elsewhere, we show that the structure had two building phases and in each phase the structure was realigned. In particular, we respectively date the site to 510±20 BC and 340±20 BC

L’embeddedness strutturale degli imprenditori immigrati transnazionali a Milano

In recent years, the topic of cross-border businesses developed by immigrants (transnational entrepreneurship) has emerged as one of the most interesting areas of research in studies on immigrants and their economic activities. The article presents the case of Moroccan transnational businesses in Milan, investigating the role of structural embeddedness in shaping identification and seizing of business opportunities. The study shows that Moroccan entrepreneurial activities are simultaneously connected with several countries. In particular, Moroccan entrepreneurs strongly rely on their structural embeddedness in Morocco and Italy, and co-national group to identify and take advantage of opportunities for internationalising their business

Differential morphine tolerance development in the modulation of macrophage cytokine production in mice

Morphine has been shown to affect cell-mediated and humoral immune parameters. In this study, we investigated the capacity of in vivo acute and chronic morphine treatment to modulate interleukin (IL)-10 and IL-12 production by LPS and interferon-\u3b3-stimulated resident and thioglycollate-elicited murine peritoneal macrophages and the development of tolerance to these effects. One hour after the acute administration of 5, 10, and 20 mg/Kg morphine, a dose-related decrease of IL-10 and IL-12 levels was present. The pretreatment with naltrexone at doses up to 20 mg/Kg did not prevent the decrease of IL-10 and IL-12 induced by morphine. When the drug was administered chronically, a differential development of tolerance to the immune effects was observed. After 3 days of treatment, the effect of the acute challenge with 20 mg/Kg morphine on IL-12 was lost. In contrast, morphine-induced inhibition of IL-10 disappeared between 10 and 12 days of treatment, in parallel with tolerance to the antinociceptive effect. These results suggest that morphine treatment affects macrophage cytokine production and that tolerance affects this modulation differently

The effects of tramadol and morphine on immune responses and pain after surgery in cancer patients

There has been growing interest in determining the possible immune consequences of opioid administration for the management of postoperative pain. We studied the effects of morphine and tramadol on pain and immune function during the postoperative period in 30 patients undergoing abdominal surgery for uterine carcinoma. Phytohemoagglutinin-induced T lymphocyte proliferation and natural killer cell activity were evaluated immediately before and after surgery, and 2 h after the acute administration of either 10 mg of morphine IM or 100 mg tramadol IM for pain. In all patients, phytohemagglutinin-induced lymphoproliferation was significantly depressed by surgical stress. However, in the morphine-treated group, proliferative values remained lower than basal levels for 2 h after treatment, whereas in tramadol-administered patients proliferative values returned to basal levels. Natural killer cell activity was not significantly affected by surgery nor by morphine administration, whereas tramadol significantly enhanced the activity of natural killer cells. Both drugs produced a comparable reduction in postoperative pain. We conclude that, as previously observed in the experimental animal, tramadol and morphine, when administered in analgesic doses, induce different immune effects

Gender and Careers in Astrophysical Science

The hard recognition of women-scientists' role is a central issue for national and supra-national institutions and organizations. Despite the growing access of women in scientific fields of study, the female presence in scientific institutes and equal career opportunities are struggling to establish themselves. These institutes refer to a gendered organizational structure able to reproduce differences in status of women and men. Focusing on the astrophysical sector, the article summarizes the results of a qualitative research that explores the role that gender plays in career paths. In fact, social and cultural practices related to gender can be considered as interpretative keys through which investigate the process of stratification and mobility and the power relations in the workplace. Within organizations, the way in which women-scientists define themselves is the result of processes that interactively act on different levels and spheres of life, and are linked to social norms and representations related to gender roles. Only re-defining the relationships that women have established with the political and social order of the scientific environment gender equality can be achieved

Qualche considerazione sulla costante di correlazione tra il lungo computo Maya ed il calendario occidentale

The remains of the Mayan civilization describe (among other things) many observations of various astronomical phenomena observed by the Maya. The modern Celestial Mechanics allows us to calculate with great accuracy when astronomical phenomena occurred and were visible in the sky for a given location on Earth too far back in time. The Maya developed the very accurate calendar known as the Long Count, but when we want to synchronize it with the western one, the correlation between the two is surprisingly very uncertain. The two calendars can be connected each other by analyzing historical data and various astronomical phenomena of which we have a paper trail in the ancient texts that is sufficient to establish an appropriate chronology. The correlation between the Long Count and the Gregorian calendar has been studied by many authors who have obtained correlation values very different from each other (almost 50 different values), which differ from one another by hundreds of years, producing considerable uncertainty in Mayan history in relation to other civilizations. Astronomy can potentially solve the problem of the correct identification of the relationship, provided that the records are available from the observations performed and documented chronologically according to the Mayan Long Count. In the present work has been performed the statistical analysis of the 52 correlations at present known and used pointing out that at the present state of knowledge it is not possible to get the exact determination of the coefficient of synchronization (correlation) between the Long Count and the Western calendar, but only an assessment of its probability distribution function, thus allowing you to assign a probability value to each value of the correlation that has been published. The statistical analysis of the 52 values at present known leads to an optimal value of the correlation constant of JDN 588159 with an uncertainty of about ±35 years

Access to liposomal generic formulations: beyond AmBisome and Doxil/Caelyx

To access this article, click on "Additional Links".The lack of clear regulatory guidance remains a key bottleneck for securing a second quality-assured source of liposomal amphotericin B (LAmB), the WHO-recommended drug for visceral leishmaniasis. The approval of the first generic liposomal product by the US Food and Drug Administration in February 2013 could be a turning point, and serve as a basis for WHO to develop guidance for the evaluation of generic liposomal formulations

Gender and Careers in Astrophysical Science

The hard recognition of women-scientists' role is a central issue for national and supra-national institutions and organizations. Despite the growing access of women in scientific fields of study, the female presence in scientific institutes and equal career opportunities are struggling to establish themselves. These institutes refer to a gendered organizational structure able to reproduce differences in status of women and men. Focusing on the astrophysical sector, the article summarizes the results of a qualitative research that explores the role that gender plays in career paths. In fact, social and cultural practices related to gender can be considered as interpretative keys through which investigate the process of stratification and mobility and the power relations in the workplace. Within organizations, the way in which women-scientists define themselves is the result of processes that interactively act on different levels and spheres of life, and are linked to social norms and representations related to gender roles. Only re-defining the relationships that women have established with the political and social order of the scientific environment gender equality can be achieved