An Engineering Approach towards Action Refinement

In the abstract modelling of distributed systems we may need methods to replace abstract behaviours by more concrete behaviours which are closer to implementation mechanisms. Furthermore, we may want these methods to preserve the correctness of such a replacement. This paper introduces an approach towards action refinement in which an abstract action is replaced by a concrete activity. This approach is based on a careful consideration of the `action' and `causality relation' architectural concepts, which enable an abstract action to be replaced by many alternative concrete activities in a general way. This approach is based on the application of abstraction rules to determine whether a concrete activity conforms to an abstract action, considering the context in which the concrete activity and the abstract action are embedde

Detection of adulterations in food products containing milk and/or milk proteins

A critical review of the most relevant analytical methodologies for quality and authenticity control of dairy products and foods containing milk proteins is presented. Chromatographic, electrophoretic and immunological methods are used for: detection of cow's milk in ewe and goat milks, detection of whey added to milk, detection of caseins and/or whey proteins in non-lactic foods and study compounds resulting from milk proteins degradation. Techniques based on polimerase chain reaction are also suitable for detection of cow's milk on cheeses of ewe and goat milks

Streptozotocin-induced mechanical hypernociception is not dependent on hyperglycemia

Since streptozotocin (STZ)-induced diabetes is a widely used model of painful diabetic neuropathy, the aim of the present study was to design a rational protocol to investigate whether the development of mechanical hypernociception induced by STZ depends exclusively on hyperglycemia. Male Wistar rats (180-200 g; N = 6-7 per group) received a single intravenous injection of STZ at three different doses (10, 20, or 40 mg/kg). Only the higher dose (40 mg/kg) induced a significant increase in blood glucose levels, glucose tolerance and deficiency in weight gain. However, all STZ-treated rats (hyperglycemic or not) developed persistent (for at least 20 days) and indistinguishable bilateral mechanical hypernociception that was not prevented by daily insulin treatment (2 IU twice a day, sc). Systemic morphine (2 mg/kg) but not local (intraplantar) morphine treatment (8 µg/paw) significantly inhibited the mechanical hypernociception induced by STZ (10 or 40 mg/kg). In addition, intraplantar injection of STZ at doses that did not cause hyperglycemia (30, 100 or 300 µg/paw) induced ipsilateral mechanical hypernociception for at least 8 h that was inhibited by local and systemic morphine treatment (8 µg/paw or 2 mg/kg, respectively), but not by dexamethasone (1 mg/kg, sc). The results of this study demonstrate that systemic administration of STZ induces mechanical hypernociception that does not depend on hyperglycemia and intraplantar STZ induces mechanical sensitization of primary sensory neurons responsive to local morphine treatment.FAPESPCNPqPrograma de Núcleos de Excelência (PRONEX

Evaluation of cheese authenticity and proteolysis by HPLC and urea-polyacrylamide gel electrophoresis

Chromatographic and electrophoretic methods have been established as useful tools in characterising cheese ripening and in the detection of milk adulteration. The purpose of this work was to evaluate casein proteolysis of cheeses made from bovine, ovine or mixtures of bovine and ovine milks, as well as ovine cheese authenticity, for 30 days of ripening by HPLC and urea–polyacrylamide gel electrophoresis. Complementary information was obtained by both techniques when applied to the study of casein proteolysis during 30 days of ripening of ovine milk cheeses, ovine milk cheeses with 10% and 20% of bovine milk and bovine milk cheeses, manufactured according to the traditional Terrincho technology. For ovine cheeses, a-casein was the fraction that showed the higher degradation during cheese ripening. A similar behaviour was observed for ovine milk cheese with 10% of bovine milk. The profile for ovine milk cheese with 20% of bovine milk was more similar to that obtained for bovine cheese. Concerning bovine milk cheeses, electrophoresis was the most sensitive technique for the evaluation of proteolysis in these cheeses. Ten and 20% of bovine milk could be detected in ovine milk cheeses by urea–polyacrylamide gel electrophoresis and HPLC, respectively, even after 30 days of ripening.Project Agro No. 26, Medida 8, Acção 8.

The Williams Scale of Attitude toward Paganism: development and application among British Pagans

This article builds on the tradition of attitudinal measures of religiosity established by Leslie Francis and colleagues with the Francis Scale of Attitude toward Christianity (and reflected in the Sahin-Francis Scale of Attitude toward Islam, the Katz-Francis Scale of Attitude toward Judaism, and the Santosh-Francis Scale of Attitude toward Hinduism) by introducing a new measure to assess the attitudinal disposition of Pagans. A battery of items was completed by 75 members of a Pagan Summer Camp. These items were reduced to produce a 21-item scale that measured aspects of Paganism concerned with: the God/Goddess, worshipping, prayer, and coven. The scale recorded an alpha coefficient of 0.93. Construct validity of the Williams Scale of Attitude toward Paganism was demonstrated by the clear association with measures of participation in private rituals

Gold nanoparticles as a part of a photothermal therapy system.

Introduction Photothermal therapy (PTT) is attracting increased attention for the treatment of superficial localized tumors, relying on the induction of local hyperthermia of tumor cells upon their irradiation with light beams1. PTT efficacy depends, however, on the heat generated and, on the depth reached by the light. Some strategies to improve PTT efficacy includes the use of the near infrared (NIR, 650 to 900 nm) radiation to enhance the penetration depth of the light, combined with gold nanoparticles (AuNPs) to enhance the photothermal effect2. Experimental Methods Core AuNPs were synthesized by a novel method using tetrachloroauric acid and a mixture of reducing agents, and subsequently coated with a combination of hyaluronic and oleic acids, for improving the NPs biocompatibility, biodegradability, and lifetime. This coating also promotes the binding of specific cell receptors of the tumor cells. The particles were physico-chemically characterized, and in vitro and in vivo tests were carried out in breast cancer models to assess their safety and efficacy, when applied alone or combined with NIR irradiation3. Results and Discussion AuNPs presented a predominant spherical morphology with sizes under 350 nm, polydispersity index lower than 0.4 and enhanced absorbance in the NIR. The particles showed no toxicity in vitro and promising efficacy in vivo when administering the NPs in situ and later irradiating them externally. Histopathological analysis of tumors treated with both AuNPs and laser irradiation showed the presence of necrosis in most of the tumors and no effect or practically absence in healthy surrounding cells, which are very encouraging outcomes. Conclusion The results are promising, however, there is still room for improving the system, namely by reducing even more the invasiveness of the treatment through the combined use of aerogels structures. Aerogel’s unique properties4 make them ideal candidates to minimize the exposure of healthy tissues to laser radiation, acting as light and thermal insulators, as well as to incorporate the nanoparticles into their skeletal structure and thus potentiating a topical application of the particles. For these reasons, some exploratory methods were carried to produce and design aerogels structures for PTT applications

Peripheral Sensitization Increases Opioid Receptor Expression And Activation By Crotalphine In Rats

Inflammation enhances the peripheral analgesic efficacy of opioid drugs, but the mechanisms involved in this phenomenon have not been fully elucidated. Crotalphine (CRP), a peptide that was first isolated from South American rattlesnake C.d. terrificus venom, induces a potent and long-lasting anti-nociceptive effect that is mediated by the activation of peripheral opioid receptors. Because the high efficacy of CRP is only observed in the presence of inflammation, we aimed to elucidate the mechanisms involved in the CRP anti-nociceptive effect induced by inflammation. Using real-time RT-PCR, western blot analysis and ELISA assays, we demonstrate that the intraplantar injection of prostaglandin E2 (PGE2) increases the mRNA and protein levels of the μ- and κ-opioid receptors in the dorsal root ganglia (DRG) and paw tissue of rats within 3 h of the injection. Using conformation state-sensitive antibodies that recognize activated opioid receptors, we show that PGE 2, alone does not increase the activation of these opioid receptors but that in the presence of PGE2, the activation of specific opioid receptors by CRP and selective μ- and κ-opioid receptor agonists (positive controls) increases. Furthermore, PGE2 down-regulated the expression and activation of the δ-opioid receptor. CRP increased the level of activated mitogen-activated protein kinases in cultured DRG neurons, and this increase was dependent on the activation of protein kinase Cζ. This CRP effect was much more prominent when the cells were pretreated with PGE 2. 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10.1124/mol.64.2.202Shaqura, M.A., Zollner, C., Mousa, S.A., Stein, C., Schafer, M., Characterization of mu Opioid Receptor Binding and G Protein Coupling in Rat Hypothalamus, Spinal Cord, and Primary Afferent Neurons during Inflammatory Pain (2004) Journal of Pharmacology and Experimental Therapeutics, 308 (2), pp. 712-718. , DOI 10.1124/jpet.103.057257Antonijevic, I., Mousa, S.A., Schafer, M., Stein, C., Perineurial defect and peripheral opioid analgesia in inflammation (1995) J Neurosci, 15, pp. 165-172Mousa, S.A., Zhang, Q., Sitte, N., Ji, R.-R., Stein, C., beta-endorphin-containing memory-cells and mu-opioid receptors undergo transport to peripheral inflamed tissue (2001) Journal of Neuroimmunology, 115 (1-2), pp. 71-78. , DOI 10.1016/S0165-5728(01)00271-5, PII S0165572801002715Konno, K., Picolo, G., Gutierrez, V.P., Brigatte, P., Zambelli, V.O., Crotalphine, a novel potent analgesic peptide from the venom of the South American rattlesnake Crotalus durissus terrificus (2008) 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Waltner-Law, M.E., Entingh, A.J., Chytil, A., Aakre, M.E., Norgaard, P., Moses, H.L., Salicylate-induced growth arrest is associated with inhibition of p70s6k and down-regulation of c-Myc, cyclin D1, cyclin A, and proliferating cell nuclear antigen (2000) Journal of Biological Chemistry, 275 (49), pp. 38261-38267. , DOI 10.1074/jbc.M005545200Belcheva, M.M., Clark, A.L., Haas, P.D., Serna, J.S., Hahn, J.W., Kiss, A., Coscia, C.J., Mu and kappa opioid receptors activate ERK/MAPK via different protein kinase C isoforms and secondary messengers in astrocytes (2005) Journal of Biological Chemistry, 280 (30), pp. 27662-27669. , DOI 10.1074/jbc.M502593200Connor, M., Christie, M.J., Opioid receptor signalling mechanisms (1999) Clinical and Experimental Pharmacology and Physiology, 26 (7), pp. 493-499. , DOI 10.1046/j.1440-1681.1999.03049.xZimmermann, M., Ethical guidelines for investigations of experimental pain in conscious animals (1983) Pain, 16, pp. 109-110Picolo, G., Giorgi, R., Bernardi, 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Water stress indicators during one stress cycle in an intensive olive orchard

The identification of a reliable and practical water stress indicator and the corresponding threshold value, for irrigation scheduling, is a classical concern in water management in agriculture. This is not well solved for woody crops, especially those not traditionally irrigated, usually with large roots systems. Aiming to contribute to these studies, we measured water fluxes and some water stress indicators in an olive grove in south Portugal, during successive stress cycles. We report the first preliminary results during a stress cycle in August-September 2011, using sap flow, leaf water potential at predawn, stem diameter variations and soil water content, from which some indicators were derived. From the preliminary information obtained we could not identify a threshold value but very good relationships were found, between the selected automated and not automated variables, useful for farmers and engineering applications. These first encouraging results need confirmation and further analysi