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1.
PLoS One ; 19(7): e0302563, 2024.
Article in English | MEDLINE | ID: mdl-38985774

ABSTRACT

Research on personal adornments depends on the reliable characterisation of materials to trace provenance and model complex social networks. However, many analytical techniques require the transfer of materials from the museum to the laboratory, involving high insurance costs and limiting the number of items that can be analysed, making the process of empirical data collection a complicated, expensive and time-consuming routine. In this study, we compiled the largest geochemical dataset of Iberian personal adornments (n = 1243 samples) by coupling X-ray fluorescence compositional data with their respective X-ray diffraction mineral labels. This allowed us to develop a machine learning-based framework for the prediction of bead-forming minerals by training and benchmarking 13 of the most widely used supervised algorithms. As a proof of concept, we developed a multiclass model and evaluated its performance on two assemblages from different Portuguese sites with current mineralogical characterisation: Cova das Lapas (n = 15 samples) and Gruta da Marmota (n = 10 samples). Our results showed that decisión-tres based classifiers outperformed other classification logics given the discriminative importance of some chemical elements in determining the mineral phase, which fits particularly well with the decision-making process of this type of model. The comparison of results between the different validation sets and the proof-of-concept has highlighted the risk of using synthetic data to handle imbalance and the main limitation of the framework: its restrictive class system. We conclude that the presented approach can successfully assist in the mineral classification workflow when specific analyses are not available, saving time and allowing a transparent and straightforward assessment of model predictions. Furthermore, we propose a workflow for the interpretation of predictions using the model outputs as compound responses enabling an uncertainty reduction approach currently used by our team. The Python-based framework is packaged in a public repository and includes all the necessary resources for its reusability without the need for any installation.


Subject(s)
Minerals , Minerals/analysis , Minerals/chemistry , Algorithms , Portugal , X-Ray Diffraction , Spectrometry, X-Ray Emission/methods , Humans , Machine Learning , Supervised Machine Learning
2.
PLoS One ; 14(5): e0215469, 2019.
Article in English | MEDLINE | ID: mdl-31051007

ABSTRACT

A group of beads from the artificial cave of La Molina (Lora de Estepa, Sevilla) and Cova del Gegant (Sitges, Barcelona) were made from a biogenic raw material and intentionally covered by a layer of resin. This is the first time this type of treatment has been documented on elements of adornment in the Late Prehistory of the Iberian Peninsula. The composition and nature of the coatings are analysed and the symbolic role of such alterations and imitations of prehistoric adornments is discussed.


Subject(s)
Amber/history , Pinus/ultrastructure , Archaeology , Geological Phenomena , History, Ancient , Spain , Spectrophotometry, Infrared , X-Ray Diffraction
3.
J Phys Chem B ; 118(13): 3650-60, 2014 Apr 03.
Article in English | MEDLINE | ID: mdl-24611839

ABSTRACT

In this work, a study for understanding the role played by [ClBmim], [BF4Bmim], [PF6Bmim], and [CH3SO3Bmim] ionic liquids (ILs) in the synthesis of zeolites is presented. The use of [ClBmim] and [CH3SO3Bmim] ILs, as reported earlier [ Chem. Eur. J. 2013 , 19 , 2122 ] led to the formation of MFI or BEA type zeolites. Contrary, [BF4Bmim] and [PF6Bmim] ILs did not succeed in organizing the Si-Al network into a zeolite structure. To try to explain these results, a series of quantum mechanical calculations considering monomers ([XBmim]) and dimers ([XBmim]2) by themselves and plus cosolvent (water or ethanol) were carried out, where X ≡ Cl(-), BF4(-), PF6(-), or CH3SO3(-). Our attention was focused on the similarities and differences among the two types of cosolvents and the relation between the structure and the multiple factors defining the interactions among the ILs and the cosolvent. Although a specific pattern based on local structures explaining the different behavior of these ILs as a zeolite structuring template was not found, the calculated interaction energies involving the Cl(-) and CH3SO3(-) anions were very close and larger than those for BF4(-) and PF6(-) species. These differences in energy can be used as an argument to describe their different behavior as structure directing agents. Moreover, the topology of the cosolvent is also an ingredient to take into account for a proper understanding of the results.

4.
Food Chem ; 139(1-4): 184-95, 2013 Aug 15.
Article in English | MEDLINE | ID: mdl-23561095

ABSTRACT

The crystallisation and polymorphic properties of three sunflower hard stearins (SHSs) and cocoa butter equivalents (CBEs) formulated by blending SHSs and palm mid fraction (PMF) were studied and compared with those from cocoa butter (CB), to explore their possibilities as confectionery fats. The isothermal crystallisation kinetics of these fats were examined by pNMR and DSC at three different temperatures. All samples studied displayed a two-step crystallisation profile that could be fitted to an exponential-Gompertz equation. Stop-and-return DSC studies showed that SHSs and CBEs exhibited different crystallisation mechanisms according to their triacylglycerol composition, with a quick formation of metastable crystals, followed by a polymorphic transition to the more stable ß or ß' forms. X-ray diffraction (XRD) was used to investigate the polymorphic forms of tempered SHSs and CBEs in the long term. In all cases the resulting fats displayed short spacing patterns associated with ß polymorphism. These formulations based on SHSs and PMF met all the requirements to be considered as CBEs; therefore they could be used as an alternative to traditional confectionery fats.


Subject(s)
Fats/chemistry , Helianthus/chemistry , Triglycerides/chemistry , Crystallization , Kinetics , Temperature , X-Ray Diffraction
5.
Arterioscler Thromb Vasc Biol ; 33(1): 96-104, 2013 Jan.
Article in English | MEDLINE | ID: mdl-23117657

ABSTRACT

OBJECTIVE: Angiotensin-II (Ang-II) promotes the interaction of mononuclear cells with arterioles and neutrophils with postcapillary venules. To investigate the mechanisms underlying this dissimilar response, the involvement of fractalkine (CX(3)CL1) was explored. METHODS AND RESULTS: Enhanced CX(3)CL1 expression was detected in both cremasteric arterioles and postcapillary venules 24 hours after Ang-II intrascrotal injection. Arteriolar leukocyte adhesion was the unique parameter significantly reduced (83%) in animals lacking CX(3)CL1 receptor (CX(3)CR1). Human umbilical arterial and venous endothelial cell stimulation with 1 µmol/L Ang-II increased CX(3)CL1 expression, yet neutralization of CX(3)CL1 activity only significantly inhibited Ang-II-induced mononuclear cell-human umbilical arterial endothelial cell interactions (73%) but not with human umbilical venous endothelial cells. The use of small interfering RNA revealed the involvement of tumor necrosis factor-α in Ang-II-induced CX(3)CL1 upregulation and mononuclear cell arrest. Nox5 knockdown with small interfering RNA or pharmacological inhibition of extracellular signal-regulated kinases1/2, p38 mitogen-activated protein kinase, and nuclear factor-κB also abolished these responses. Finally, when human umbilical arterial endothelial cells were costimulated with Ang-II, tumor necrosis factor-α, and interferon-γ, CX(3)CL1 expression and mononuclear cell adhesiveness were more pronounced than when each stimulus was provided alone. CONCLUSIONS: These results suggest that Ang-II induces functional CX(3)CL1 expression in arterial but not in venous endothelia. Thus, targeting endothelial CX(3)CL1-mononuclear leukocyte CX(3)CR1 interactions may constitute a new therapeutic strategy in the treatment of Ang-II-associated cardiovascular diseases.


Subject(s)
Angiotensin II/metabolism , Arteries/metabolism , Chemokine CX3CL1/metabolism , Endothelial Cells/metabolism , Veins/metabolism , Angiotensin II Type 1 Receptor Blockers/pharmacology , Animals , Apolipoproteins E/genetics , Apolipoproteins E/metabolism , Arteries/drug effects , Arterioles/drug effects , Arterioles/metabolism , Atherosclerosis/genetics , Atherosclerosis/metabolism , Atherosclerosis/pathology , Atherosclerosis/prevention & control , CX3C Chemokine Receptor 1 , Cell Adhesion , Cells, Cultured , Chemokine CX3CL1/genetics , Disease Models, Animal , Endothelial Cells/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Human Umbilical Vein Endothelial Cells/metabolism , Humans , Interferon-gamma/metabolism , Leukocyte Rolling , Leukocytes/metabolism , Losartan/pharmacology , Male , Membrane Glycoproteins/genetics , Membrane Glycoproteins/metabolism , Membrane Proteins/genetics , Membrane Proteins/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , NADPH Oxidase 2 , NADPH Oxidase 4 , NADPH Oxidase 5 , NADPH Oxidases/genetics , NADPH Oxidases/metabolism , NF-kappa B/metabolism , RNA Interference , Receptors, Chemokine/genetics , Receptors, Chemokine/metabolism , Signal Transduction , Time Factors , Transfection , Tumor Necrosis Factor-alpha/genetics , Tumor Necrosis Factor-alpha/metabolism , Veins/drug effects , Venules/drug effects , Venules/metabolism
6.
Chemistry ; 19(6): 2122-30, 2013 Feb 04.
Article in English | MEDLINE | ID: mdl-23255393

ABSTRACT

This study reports the use of 1-butyl-3-methyl imidazolium methanesulfonate ionic liquid as a template in the synthesis of zeolites. It is found that the silicon source determines the formation of beta (BEA), mordenite framework inverted (MFI), or analcime (ANA) zeolites. Depending on this source, different preorganized complexes are obtained that drive the formation of the different zeolite structures. In the presence of ethanol, the ionic liquid form preorganized complexes that drive the formation of MFI. In its absence, BEA is obtained. Whereas, the large amount of sodium present when using sodium metasilicate leads to ANA formation. A molecular simulation study of the relative stability of the template-framework system and location of the template provides further insight into the mechanism of synthesis.

7.
Rev Esp Quimioter ; 24(4): 233-62, 2011 Dec.
Article in English | MEDLINE | ID: mdl-22173195

ABSTRACT

Diabetic foot infection, particularly if it is associated to ischaemia,is the most common cause of lower limb amputation, in the general population, of hospital admissions, and a decrease in the quality of life in diabetics. Of all diabetics, 15% of them are going to suffer from a foot infection during their life, with an annual incidence of 1-4%, preceded by a foot ulcer in more than 80% of cases. They are complex infections and the prognosis is influenced by many factors, depending on the ulcer (location, extension, whether chronic or not, previous amputation, ischaemia grade), and the patient (age, renal impairment, time of onset of diabetes, associated comorbidity). All these must be taken into account when establishing its treatment. The infections must be classified according to their severity (mild, moderate-mild, moderatesevere, and severe). Their treatment is complex and must be multidisciplinary and must include debridement, discharge, adequate antibiotic therapy, revascularisation, and treatment of the ulcer. In this consensus document, produced in collaboration with the Spanish Angiology and Vascular Surgery Society (SEACV), the Spanish Society of Internal Medicine (SEMI), the Spanish Chemotherapy Society (SEQ), the Spanish Surgeons Association (AEC), the Spanish Society of Urgent Medicine and Emergencies (INFURG-SEMES) and the Spanish Society of Intensive and Critical Medicine and Coronary Care (SEMICYUC), the guidelines are developed based on the best available evidence on diabetic foot infections, aimed at achieving greater clinical efficacy.


Subject(s)
Diabetic Foot/complications , Infections/drug therapy , Infections/surgery , Anti-Bacterial Agents/therapeutic use , Biomarkers , Consensus , Debridement , Diabetic Foot/classification , Diabetic Foot/epidemiology , Diabetic Foot/physiopathology , Diabetic Foot/surgery , Guidelines as Topic , Hospital Units , Humans , Infections/classification , Infections/diagnosis , Infections/etiology , Infections/microbiology , Ischemia/etiology , Ischemia/therapy , Osteomyelitis/complications
8.
Cardiovasc Res ; 92(1): 48-56, 2011 Oct 01.
Article in English | MEDLINE | ID: mdl-21622682

ABSTRACT

AIMS: In vitro studies suggest that mast cell chymase (MCP) is more important than angiotensin-converting enzyme (ACE) for generating angiotensin II (Ang II) within the cardiovascular system. We investigated in vivo the relative contributions of ACE and MCP to leucocyte recruitment induced by endogenously generated Ang II. METHODS AND RESULTS: Exposure of the murine cremasteric microcirculation of C57BL/6 mice to Ang I (100 nM for 4 h) induced leucocyte-endothelium interactions. Either losartan (an Ang II receptor-1 antagonist, AT(1)) or enalapril (an ACE inhibitor), but not chymostatin (a chymase inhibitor), inhibited Ang I-induced responses. Mast cell degranulation with compound 48/80 (CMP48/80, 1 µg/mL) also induced leucocyte adhesion but this was only weakly affected by the inhibitors. When Ang I and CMP48/80 were co-administered, AT(1B) receptor expression was increased, MCP-4 was found surrounding the vessel wall, and ACE was detected in the endothelium. Ang I + CMP48/80 induced enhanced leucocyte adhesion that was attenuated by losartan, enalapril, enalapril + chymostatin, and cromolyn (a mast cell stabilizer). The use of male mast cell-deficient WBB6F1/J-Kit(w)/Kit(w-v) mice (C57BL/6 background) confirmed these findings. CONCLUSION: In vivo, Ang II is primarily generated by ACE under basal conditions, but in inflammatory conditions, the release of MCP amplifies local Ang II concentrations and the associated inflammatory process. Thus, AT(1) receptor antagonists may be more effective than ACE inhibitors for treating ongoing Ang II-mediated vascular inflammation.


Subject(s)
Angiotensin II/biosynthesis , Chymases/physiology , Leukocytes/physiology , Mast Cells/enzymology , Peptidyl-Dipeptidase A/physiology , Angiotensin I/pharmacology , Animals , Cell Movement , Male , Mice , Mice, Inbred C57BL , Receptor, Angiotensin, Type 1/physiology , p-Methoxy-N-methylphenethylamine/pharmacology
9.
Rev. centroam. obstet. ginecol ; 14(4): 163-169, oct.-dic. 2009.
Article in Spanish | LILACS | ID: lil-733729

ABSTRACT

Objetivo: establecer una relación entre las alteraciones de la glucosa, la insulina, el metabolismo de los lípidos, y los niveles hormonales en relación a la obesidad y la contextura corporal en mujeres con PCOS. Pacientes y métodos: estudio observacional tipo casos-controles, con 223 pacientes diagnosticadas de síndrome de ovarios poliquísticos (SOP) según los criterios de Rotterdam, y 25 controles sanas...


Subject(s)
Female , Body Mass Index , Cholesterol, LDL/metabolism , Lipoproteins, LDL/metabolism , Lipoproteins, LDL/therapeutic use , Triglycerides/analysis , Triglycerides/metabolism
10.
La paz; GMCMM; 2009. 10 p.
Non-conventional in Spanish | LIBOCS, LIBOPI | ID: biblio-1297179

ABSTRACT

El presente capitulo pretende plantear algunas ideas inicilaes de una discusion y practica mas intensa que debera abordar el Municipio en el Marco de la Nueva Constitucion Polìtica del Estado (NCPE)

11.
La Paz; PA/OEA/FLCSSE; nov.1999. 32 p. graf.
Monography in Spanish | LIBOCS, LIBOSP | ID: biblio-1303946

ABSTRACT

En el presente articulo se describen las principales caracteristicas y el estado actual del proceso de descentralización implementado en Bolivia, en relación con sus compumentes fiscales y financieros, las politicas para su implementación, los mecanismos legales e institucionales y los procesos locales desarrollados entorno a los principales compomentes del proceso.


Subject(s)
Male , Female , Humans , Politics , Bolivia , Politics
12.
La Paz; DIAKONIA - OXFAM; Febrero, 1999. 242 p. tab.
Monography in Spanish | LIBOCS, LIBOSP | ID: biblio-1318029

ABSTRACT

El trabajo coordinado y mancomunado puede ser clave en el avance del conocimiento y desarrollo de muchas temáticas, no se trata de que las instituciones trabajen solas o aisladamente, antes bien, es preciso generar sinergisa entre varias de ellas, aunque es natural que tal trabajo conjunto se pueda realizar con más facilidad especialmente entre organizaciones que poseen preocupaciones comunes o que tienen retos y metas compartidas.


Subject(s)
Social Participation , Modernization of the Public Sector
13.
La Paz; s.n; sept. 1997. 57 p. ilus, map.
Monography in Spanish | LIBOCS, LIBOSP | ID: biblio-1300999

ABSTRACT

El siguiente trabajo de investigación se propone detectar la estructura de funcionamiento de los mercados, la estructura interna y de poder en las organizaciones de comerciantes y la posibilidad de la Alcaldia de aprovechar la misma para mejorar las condiciones de venta, sin afectar negativamente los intereses de los distintos grupos que en ella actúan


Subject(s)
Food , Commerce , Consultants , Bolivia , Cities , Hygiene/education , Research , Market Sanitation , Health Care Sector/standards
14.
La Paz; SEAMOS; 1994. 113 p. ^etbls..(Drogas: Investigación para el debate, n. 9).
Monography in Spanish | LIBOCS, LIBOSP | ID: biblio-1298825

ABSTRACT

el presente estudio quiere aportar un grano de arena a la comprensión global de la temática, proporcionando además una sinopsis de datos estadísticos, evaluaciones y opiniones generalizadas y, ante todo, avanzando algunas hipótesis para esclarecer algunos de los muchos aspectos poco analizados de la problemática.


Subject(s)
Coca , Illicit Drugs , Labor Unions , Drug Trafficking
15.
La Paz; SEAMOS; 1994. 113 p.
Monography in Spanish | LIBOCS, LILACS, LIBOSP | ID: biblio-1315419
16.
La Paz; SEAMOS; Impreso; 1994. 114 p. (Drogas: investigación para el debate, n. 9).
Monography in Spanish | LIBOCS, LIBOSP | ID: biblio-1298056

ABSTRACT

Contiene: 1. La necesidad de un esclarecimiento radical del problema global: presentación crítica del estado actual. 2. Las dimensiones del problema del complejo coca - cocaína en Bolivia y la situación en el escenario de las políticas públicas. 3. Hipótesis principales en torno a los efectos socio - políticos del complejo coca - cocaína.

17.
La Paz; SEAMOS; 1994. 114 p. ^etbls..(Drogas: investigación para el debate, n. 9).
Monography in Spanish | LIBOCS, LIBOSP | ID: biblio-1332592
18.
La Paz; SEAMOS; 1994. 113 p. (Serie \"Drogas Investigación para el Debate\", 9).
Monography in Spanish | LIBOCS, LIBOSP | ID: biblio-1302915

ABSTRACT

El presente estudio está diseñado para brindar informaciones fehacientes y análisis crítico en torno a algunos puntos de la temática coca/cocaina que ameritan un tratamiento algo diverso de los publicados hasta hoy. Brevemente se pueden mencionar los objetivos principales de este estudio de la siguiente manera: establecer algunos conocimientos fundamentados en el terreno (poco tratado hasta hoy en Bolivia) de la sociología del comportamiento frente al problema coca/cocaína, con especial referencia al componente ético-político, para detectar pautas valorativas entre grupos con algún poder de decisión e influencia, como ser dirigentes políticos y sindicales, funcionarios de la alta administración pública, periodistas y líderes de opinión


Subject(s)
Coca , Cocaine , Social Perception , Bolivia
19.
La Paz; CEBEM; 1993. 231 p.
Monography in Spanish | LIBOCS, LIBOSP | ID: biblio-1303336

ABSTRACT

Esta publicación presenta una memoria del seminario Fiananciamiento de Iniciativas Comunitarias en Asentamientos Urbanos, organizado por Centro Boliviano de Estudios Multidisciplianarios (CEBEM) y el Programa de Fortalecimiento Institucional y Capacitación de Organizaciones No Gubernamentales (FICONG) en Santa Cruz de la Sierra experiencias programadas por el FICONG


Subject(s)
Humans , Financing, Organized , Poverty , Human Settlements , Bolivia , Poverty
20.
La Paz; CEBEM; 1993. 101 p. tab.
Monography in Spanish | LIBOCS, LIBOSP | ID: biblio-1304148

ABSTRACT

En este trabajo se quiere resaltar el papel protagónico del Estado (administracion central) en la adecuación espacial para la constitución y consolidación del proceso de descentralización. En este sentido se divide en dos partes: en la primera parte se hace una descripcion de las estrategias y lineas de accion del Estado nacional; en la segunda parte se analizaalgunos puntos centrales de la institucionalidad regional.(au)


Subject(s)
Politics , Bolivia
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