A new system to measure leather shrinkage temperature

Content: A characteristic of leather is that if it is gradually heated in aqueous solution it reaches a temperature where sudden and irreversible shrinkage occurs. This phenomenon is related to the denaturalization of the collagen protein that conforms the hide and is known as leather shrinkage. Specifically, the internal bonds break thus causing a shortening of the skin that can be up to a 35% from its original length. Accordingly, one of the most used methods to check the quality of the leather tanning process is the determination of the contraction temperature according to the ISO 3380:2015 standard. This method measures the leather shrinkage when constantly increasing the sample temperature. The shrinkage temperature corresponds to the temperature when the sample suddenly contracts. The value of this temperature indicates the degree of collagen stability and therefore, when higher, the leather will have better quality and resistance. The process of leather shrinkage can be divided in different stages. Several authors discriminate temperature A1 (when the first fibre starts to shrinkage), temperature C (when there is a massive shrinkage) and finally temperature A2 (when the last fibres are contracted individually). The method that describes the ISO 3380:2015 standard uses a device where the determination of the shrinkage temperature is performed visually by the laboratory technician. Consequently, the method tends to be imprecise and subjective. It should also be noticed that the device proposed by the standard does not allow differentiation between the different stages of the contraction process. There are other methods to determine leather shrinkage temperature including differential scanning calorimetry, microscopic hot table, thermogravimetric analysis, differential thermal analysis and thermomechanical analysis. All these methods involve complex devices and are only suitable for specialized personnel. In this work, a new device is developed to precisely measure the leather shrinkage temperature and to distinguish the different contraction stages. In addition, the proposed device is simple, easy to use and inexpensive, which facilitates its use in any industry. The developed system consists basically of a load cell to measure the strength produced by the shrinkage of the leather. With the logged data during the test a strength versus temperature graph is built. By means of its interpretation, the different stages of shrinkage can be determined. Different mathematical analysis of the logged data is proposed to determine the shrinkage stages temperatures, thus achieving a high degree of certainty and repeatability. Take-Away: A new device, simple and inexpensive, is developed to precisely measure the leather shrinkage temperature and to distinguish the different contraction stages

Sistemas polimórficos de la Cerdanya y su relación con los del País Vasco

En este trabajo se ha caracterizado la población autóctona de La Cerdanya mediante el estudio serológico de los sistemas MNSs, Kell, Duffy y HLA (loci A y B), y, se ha comparado con la población vasca. Los resultados obtenidos únicamente muestran diferencias para algunos sistemas en determinadas poblaciones comparadas, lo cual parece indicar que, en el País Vasco, no existe uniformidad genética para todos los marcadores. Las características serológicas que presenta la población autóctona de la Cerdanya no demuestran una proximidad genética, como cabría esperar "a priori" dados sus antecedentes históricos y, de haber existido este patrimonio genético, debió haber sido "diluido" por la influencia de invasiones posteriores.Pour mener ce travail, nous avons voulu caractériser la Cerdagne par une étude séro-anthropologique de la population autochtone parce que les caractères sérologiques sont sous le contrôle direct du génotype et échappent totalement aux conditions du milieu. Comme cela n'avait pas encore été fait du côté sud, et du côté français, la population a été étudiée en tenant compte de l'ensemble des Pyrénées Orientales. D'autre part, l'étude des caractères morphologiques, les seuls longtemps utilisés pour caractériser les populations, avait déjà été realisée par le Dr. Alcobé, bien que la population n'était pas totalement autochtone, que ces caractères dépendent d'une herédité polymorphique et qu'ils sont influencés par le milieu.La Cerdagne est un territoire de 1.129 Km2 situé dans une vallée des Pyrénées Orientales. Elle est formée par le haut bassin du Segre et elle est entourée par des chaînes montagneuses qui atteignent presque 3.000 m. d'altitude. Cette région a été partagée de NW en SE par la frontière franco-espagnole au traité des Pyrénées, en 1660, entre Louis XIV de France et Felipe IV de Castilla, et elle a été utilisée par des peuples pré et indoeuropéens comme lieu de passage pour entrer dans la Péninsule Ibérique. A la fin de l'époque mégalithique et après pendant l'Âge du Bronze, des populations brachycéphales sont venues du Centre de l'Europe vers les Pyrénées et ont pénétré par la Cerdagne dans la Péninsule Ibérique influant sur les populations autochtones qui avaient un élément dolichocéphale. Les événements de ces époques associés à des études de toponymies semblent indiquer que le peuple primitif de la Cerdagne pourrait avoir des affinités avec les peuples franco-cantabriques, lesquels parlaient une langue commune pré-indoeuropéenne de type basque, comme l'indique un grand nombre de noms de villages de type basque qui existent en Cerdagne: Das, Êller, Urtx, Urús, Ur, Ix, Er, Naüja, etc. En même temps, les anciens cerdagniens sont rapportés, par des romains, comme des "Kerretani". Ce mot provient du mot basque "Kerr", ou "xerri". Ces faits nous amenent à considérer si des analogies possibles existent entre la population basque et celle de la Cerdagne ou bien, au contraire, si tous les deux différent génétiquement. Le présent travail a été réalisé dans la Basse Cerdagne (côté sud) qui a 603.36 Km2 , dont la densité de population atteint seulement 22 hab/km2 et la population autochtone n'atteint pas 30%. Les marqueurs sérologiques (systèmes érythrocytaires Duffy, Kell, MNSs et le système lymphocytaire HLA -loci A, B-) ont étéanalysés sur 140 individus autochtones, sans apparentement connu jusqu'a 1/8. Les résultats obtenus témoignent, en général, d'une conduite inégale à l'ègard des différentes populations basques avec lesquelles nous les avons comparés. Il faut tenir compte du travail présenté par Malgosa à ce congrès intitulé: "Êtude des systèmes sanguins ABO, Lewis, P et Rh dans la population autochtone de la Cerdagne. Relation avec la population basque"

Diversity of the Ganoderma species in Uruguay

Ganoderma is a cosmopolitan genus that includes a great diversity of species. Many of them have been historically described based only on morphological characteristics; however, due to their morphological plasticity, there is no complete understanding about their relationship and taxonomic status. Commonly applied names, particularly in the southern Neotropics, come from species of North Hemisphere distribution (e.g. G. lucidum, G. resinaceum and G. applanatum). The objective of the present work was to perform a survey of Ganoderma species thriving in Uruguay. We aimed to identify and characterize them through molecular, morphological and ecological analysis. The results confirm the presence of four reddish laccate species first registered for Uruguay (G. dorsale, G. platense, G. martinicense and G. mexicanum), and one non-laccate species (G. australe s.l.) composed of two clades. The species are morphologically differentiated mainly by its stipe, pilear surface, context, pores, basidiospores and cutis cells. Regarding the ecological data, the species present differences in substrate preferences. In addition, a taxonomic discussion regarding phylogenetic relationships and taxonomic status of Uruguayan Ganoderma species is presented

Soil degradation and socioeconomic systems’ complexity: Uncovering the latent nexus

Understanding Soil Degradation Processes (SDPs) is a fundamental issue for humankind. Soil degradation involves complex processes that are influenced by a multifaceted ensemble of socioeconomic and ecological factors at vastly different spatial scales. Desertification risk (the ultimate outcome of soil degradation, seen as an irreversible process of natural resource destruction) and socioeconomic trends have been recently analyzed assuming “resilience thinking” as an appropriate interpretative paradigm. In a purely socioeconomic dimension, resilience is defined as the ability of a local system to react to external signals and to promote future development. This ability is intrinsically bonded with the socio-ecological dynamics characteristic of environmentally homogeneous districts. However, an evaluation of the relationship between SDPs and socioeconomic resilience in local systems is missing in mainstream literature. Our commentary formulates an exploratory framework for the assessment of soil degradation, intended as a dynamic process of natural resource depletion, and the level of socioeconomic resilience in local systems. Such a framework is intended to provide a suitable background to sustainability science and regional policies at the base of truly resilient local systems

Equivalence problem for the orthogonal webs on the sphere

We solve the equivalence problem for the orthogonally separable webs on the three-sphere under the action of the isometry group. This continues a classical project initiated by Olevsky in which he solved the corresponding canonical forms problem. The solution to the equivalence problem together with the results by Olevsky forms a complete solution to the problem of orthogonal separation of variables to the Hamilton-Jacobi equation defined on the three-sphere via orthogonal separation of variables. It is based on invariant properties of the characteristic Killing two-tensors in addition to properties of the corresponding algebraic curvature tensor and the associated Ricci tensor. The result is illustrated by a non-trivial application to a natural Hamiltonian defined on the three-sphere.Comment: 32 page

Land degradation and mitigation policies in the mediterranean region. A brief commentary

Land degradation is more evident where conditions of environmental vulnerability already exist because of arid climate and unsustainable forms of land exploitation. Consequently, semi-arid and dry areas have been identified as vulnerable land, requiring attention from both science and policy perspectives. In some regions, such as the Mediterranean region, land degradation is particularly intense, although there are no extreme ecological conditions. In these contexts, a wide range of formal and informal responses is necessary to face particularly complex and spatially differentiated territorial processes. However, the fit of responses has been demonstrated to be different over time and space according to the underlying socioeconomic context and the specific ecological conditions. The present commentary discusses this sort of \u201centropy\u201d in the policy response to land degradation in Southern Europe, outlining the intrinsic complexity of human\u2013nature dynamics at the base of such processes. Reflecting the need of differentiated regional strategies and more specific national measures to combat desertification, three policy frameworks (agro-environmental, economic, social) with an indirect impact on fighting land degradation have been considered, delineating the importance of policy assemblages. Finally, the importance of policy impact assessment methodologies was highlighted, focusing on the possible responses reinforcing a continental strategy against land degradation. By evidencing the role of participatory planning, developmental policies indirectly addressing land degradation reveal to be an important vector of more specific measures abating desertification risk, creating, in turn, a favorable context for direct interventions of mitigation or adaptation to climate change

Antinociceptive effects of tetrazole inhibitors of endocannabinoid inactivation: Cannabinoid and non-cannabinoid receptor-mediated mechanisms

Background and purpose: Tetrazoles were recently developed as inhibitors of the cellular uptake of the endocannabinoid anandamide or of its hydrolysis by fatty acid amide hydrolase (FAAH), but were proposed to act also on non-endocannabinoid-related serine hydrolases. Experimental approach: We tested, in a model of inflammatory pain induced in mice by formalin, five chemically similar inhibitors: (i) OMDM119 and OMDM122, two potent carbamoyl tetrazole FAAH inhibitors with no effect on anandamide uptake; (ii) LY2183240, a carbamoyl tetrazole with activity as both FAAH and uptake inhibitor; (iii) OMDM132, a non-carbamoyl tetrazole with activity only as uptake inhibitor and iv) OMDM133, a non-carbamoyl tetrazole with no activity at either FAAH or uptake. Results: All compounds (2.5-10 mg kg -1, i.p.) inhibited the second phase of the nocifensive response induced by intraplantar injection of formalin. The effects of OMDM119, OMDM122 and OMDM133 were not antagonized by pretreatment with cannabinoid CB 1 receptor antagonists, such as rimonabant or AM251 (1-3 mg kg -1, i.p.). The effects of LY2183240 and OMDM132 were fully or partially antagonized by rimonabant, respectively, and the latter compound was also partly antagonized by the CB 2 receptor antagonist, AM630. Conclusions and implications: (i) non-FAAH hydrolases might be entirely responsible for the antinociceptive activity of some, but not all, tetrazole FAAH inhibitors, (ii) the presence of a carbamoylating group is neither necessary nor sufficient for such compounds to act through targets other than FAAH and (iii) inhibition of anandamide uptake is responsible for part of this antinociceptive activity, independently of effects on FAAH. © 2008 Macmillan Publishers Limited All rights reserved

Clinical value of bioelectrical properties of cancerous tissue in advanced epithelial ovarian cancer patients

Currently, there are no valid pre-operatively established biomarkers or algorithms that can accurately predict surgical and clinical outcome for patients with advanced epithelial ovarian cancer (EOC). In this study, we suggest that profiling of tumour parameters such as bioelectrical-potential and metabolites, detectable by electronic sensors, could facilitate the future development of devices to better monitor disease and predict surgical and treatment outcomes. Biopotential was recorded, using a potentiometric measurement system, in ex vivo paired non-cancerous and cancerous omental tissues from advanced stage EOC (n = 36), and lysates collected for metabolite measurement by microdialysis. Consistently different biopotential values were detected in cancerous tissue versus non-cancerous tissue across all cases (p < 0.001). High tumour biopotential levels correlated with advanced tumour stage (p = 0.048) and tumour load, and negatively correlated with stroma. Within our EOC cohort and specifically the high-grade serous subtype, low biopotential levels associated with poorer progression-free survival (p = 0.0179, p = 0.0143 respectively). Changes in biopotential levels significantly correlated with common apoptosis related pathways. Lactate and glucose levels measured in paired tissues showed significantly higher lactate/glucose ratio in tissues with low biopotential (p < 0.01, n = 12). Our study proposes the feasibility of biopotential and metabolite monitoring as a biomarker modality profiling EOC to predict surgical and clinical outcomes

La comprensión de las Organizaciones productoras de servicios sociales desde el paradigma de los sistemas complejos

English abstractResumen en españo

On the Equivalence Between Type I Liouville Dynamical Systems in the Plane and the Sphere

Producción CientíficaSeparable Hamiltonian systems either in sphero-conical coordinates on an S2 sphere or in elliptic coordinates on a R2 plane are described in a unified way. A back and forth route connecting these Liouville Type I separable systems is unveiled. It is shown how the gnomonic projection and its inverse map allow us to pass from a Liouville Type I separable system with a spherical configuration space to its Liouville Type I partners where the configuration space is a plane and back. Several selected spherical separable systems and their planar cousins are discussed in a classical context