Showing papers by "Rovira i Virgili University published in 2011"

The Twentieth Century Reanalysis Project

Abstract: The Twentieth Century Reanalysis (20CR) project is an international effort to produce a comprehensive global atmospheric circulation dataset spanning the twentieth century, assimilating only surface pressure reports and using observed monthly sea-surface temperature and sea-ice distributions as boundary conditions. It is chiefly motivated by a need to provide an observational dataset with quantified uncertainties for validations of climate model simulations of the twentieth century on all time-scales, with emphasis on the statistics of daily weather. It uses an Ensemble Kalman Filter data assimilation method with background ‘first guess’ fields supplied by an ensemble of forecasts from a global numerical weather prediction model. This directly yields a global analysis every 6 hours as the most likely state of the atmosphere, and also an uncertainty estimate of that analysis. The 20CR dataset provides the first estimates of global tropospheric variability, and of the dataset's time-varying quality, from 1871 to the present at 6-hourly temporal and 2° spatial resolutions. Intercomparisons with independent radiosonde data indicate that the reanalyses are generally of high quality. The quality in the extratropical Northern Hemisphere throughout the century is similar to that of current three-day operational NWP forecasts. Intercomparisons over the second half-century of these surface-based reanalyses with other reanalyses that also make use of upper-air and satellite data are equally encouraging. It is anticipated that the 20CR dataset will be a valuable resource to the climate research community for both model validations and diagnostic studies. Some surprising results are already evident. For instance, the long-term trends of indices representing the North Atlantic Oscillation, the tropical Pacific Walker Circulation, and the Pacific–North American pattern are weak or non-existent over the full period of record. The long-term trends of zonally averaged precipitation minus evaporation also differ in character from those in climate model simulations of the twentieth century. Copyright © 2011 Royal Meteorological Society and Crown Copyright.

Explosive synchronization transitions in scale-free networks.

Abstract: Explosive collective phenomena have attracted much attention since the discovery of an explosive percolation transition. In this Letter, we demonstrate how an explosive transition shows up in the synchronization of scale-free networks by incorporating a microscopic correlation between the structural and the dynamical properties of the system. The characteristics of the explosive transition are analytically studied in a star graph reproducing the results obtained in synthetic networks. Our findings represent the first abrupt synchronization transition in complex networks and provide a deeper understanding of the microscopic roots of explosive critical phenomena.

Modeling human mobility responses to the large-scale spreading of infectious diseases

Abstract: Current modeling of infectious diseases allows for the study of realistic scenarios that include population heterogeneity, social structures, and mobility processes down to the individual level. The advances in the realism of epidemic description call for the explicit modeling of individual behavioral responses to the presence of disease within modeling frameworks. Here we formulate and analyze a metapopulation model that incorporates several scenarios of self-initiated behavioral changes into the mobility patterns of individuals. We find that prevalence-based travel limitations do not alter the epidemic invasion threshold. Strikingly, we observe in both synthetic and data-driven numerical simulations that when travelers decide to avoid locations with high levels of prevalence, this self-initiated behavioral change may enhance disease spreading. Our results point out that the real-time availability of information on the disease and the ensuing behavioral changes in the population may produce a negative impact on disease containment and mitigation.

Endohedral metallofullerenes: a unique host–guest association

Abstract: In this tutorial review taking X-ray crystallographically characterized compounds as a starting point a walk is taken through the electronic and structural properties of endohedral metallofullerenes After classification of the fullerenes according to the encapsulated guest, particular attention is given to identifying factors that determine the selection of a particular carbon cage network by the internal metal cluster Some of the physical rules that determine which particular fullerene cage is formed will be discussed Concepts such as charge transfer between the cage and the guest metal ions, the topology of the cage, the separations between the 12 pentagons on the fullerene surface, and the effect of entropic factors are used to rationalize the selection of a particular cage The roles of electrochemistry and vibrational spectroscopy in combination with theoretical calculations are considered in understanding the structures of the endohedral fullerenes

Use of a high-throughput screening approach coupled with in vivo zebrafish embryo screening to develop hazard ranking for engineered nanomaterials.

Abstract: Because of concerns about the safety of a growing number of engineered nanomaterials (ENM), it is necessary to develop high-throughput screening and in silico data transformation tools that can speed up in vitro hazard ranking. Here, we report the use of a multiparametric, automated screening assay that incorporates sublethal and lethal cellular injury responses to perform high-throughput analysis of a batch of commercial metal/metal oxide nanoparticles (NP) with the inclusion of a quantum dot (QD1). The responses chosen for tracking cellular injury through automated epifluorescence microscopy included ROS production, intracellular calcium flux, mitochondrial depolarization, and plasma membrane permeability. The z-score transformed high volume data set was used to construct heat maps for in vitro hazard ranking as well as showing the similarity patterns of NPs and response parameters through the use of self-organizing maps (SOM). Among the materials analyzed, QD1 and nano-ZnO showed the most prominent let...

Phosphite-containing ligands for asymmetric catalysis.

Abstract: Phosphite-Containing Ligands for Asymmetric Catalysis PietW. N.M. van Leeuwen, Paul C. J. Kamer,Carmen Claver,Oscar P amies,* andMontserrat Di eguez* Institute of Chemical Research of Catalonia, Avinguda Països Catalans 16, 43007 Tarragona, Spain University of St. Andrews, EaStCHEM, School of Chemistry, St. Andrews, Fife KY16 9ST, United Kingdom Universitat Rovira i Virgili, Departament de Química Física i Inorg anica, C/Marcel 3 lí Domingo s/n, 43007 Tarragona, Spain

Effects of one serving of mixed nuts on serum lipids, insulin resistance and inflammatory markers in patients with the metabolic syndrome.

Abstract: Background and aims: Knowledge of the effect of nut consumption on metabolic syndrome (MetS) components is limited. We assessed the effects of nut intake on adiposity, serum lipids, insulin resistance, and inflammatory biomarkers in patients with MetS. Methods and results: In a randomized, parallel-group, 12-week feeding trial, 50 patients with MetS were given recommendations for a healthy diet with or without supplementation with 30 g/day of raw nuts (15 g walnuts, 7.5 g almonds and 7.5 g hazelnuts) (Nut and Control diet groups, respectively). Adiposity measures, serum lipids, insulin, Homeostasis Model Assess- ment (HOMA), interleukin-6 (IL-6) and other inflammatory biomarkers, and 48-h fecal fat were determined basally and at study's completion. Moderate weight loss, decreased adiposity, and lower blood pressure occurred similarly after both diets. The Control, but not the Nut diet, was associated with significant (P <0.05) reduction of LDL-cholesterol, with mean changes of Abbreviations: MetS, metabolic syndrome; HOMA, Homeostasis Model Assessment; CVD, cardiovascular disease; ATP III, Adult Treatment Panel III; REE, resting energy expenditure; O2, oxygen; CO2, carbon dioxide; SFA, saturated fatty acid; CRP, C-reactive protein; IL-6, interleukin-6; MCP-1, monocyte chemotactic protein-1; PAI-1, plasminogen activator inhibitor-1; IL-18, interleukin-18; ANCOVA, analysis of covariance; MUFA, monounsaturated fatty acid; PUFA, polyunsaturated fatty acid. * Support for research: Supported by grants from the Spanish Ministry of Education and Science (CICYT-AGL2005-03605), Spanish Ministry of Health (RTIC RD06/0045) and the International Nut Council. The nuts used in the study were donated by Borges S.A., Reus, Spain. None of the funding sources played a role in the design, collection, analysis or interpretation of the data or in the decision to submit the manuscript for publication. Patricia Lopez-Uriarte is a recipient of a predoctoral fellowship from the Generalitat de Catalunya's Ministry of Universities, Research and the Information Society and the European Social Funds.

Human Exposure to Arsenic, Cadmium, Mercury, and Lead from Foods in Catalonia, Spain: Temporal Trend

Abstract: The main purpose of this study was to establish the temporal trend in the daily dietary intake of arsenic (As), cadmium (Cd), mercury (Hg), and lead (Pb) by the population of Catalonia, Spain. Concentrations of these elements were determined in samples of a number of food items widely consumed in that country. The dietary intake of As, Cd, Hg, and Pb was then estimated for various age–gender groups of population: children, adolescents, adults, and seniors. In the present study, the dietary intakes of As, inorganic As, Cd, Hg, methylmercury, and Pb were 328.37, 16.22, 19.47, 11.39, 10.25, and 101.47 μg/day, respectively, while in a previous (2006) survey, the dietary intakes of As, inorganic As, Cd, Hg, methylmercury, and Pb were 261.01, 33.17, 9.80, 12.61, 11.35, and 45.13 μg/day, respectively. The estimated intakes of Cd, Hg, and Pb are still notably lower than the respective PTWIs, while that of inorganic As is also lower than its BMDL01. In summary, the results of this study indicate that, currently, the dietary intakes of As, Cd, Hg, and Pb should not mean additional health risks for the consumers.

New adipokines vaspin and omentin. Circulating levels and gene expression in adipose tissue from morbidly obese women

Abstract: Vaspin and omentin are recently described molecules that belong to the adipokine family and seem to be related to metabolic risk factors. The objectives of this study were twofold: to evaluate vaspin and omentin circulating levels and mRNA expression in subcutaneous and visceral adipose tissues in non-diabetic morbidly obese women; and to assess the relationship of vaspin and omentin with anthropometric and metabolic parameters, and other adipo/cytokines. We analysed vaspin and omentin circulating levels in 71 women of European descent (40 morbidly obese [BMI ≥ 40 kg/m2] and 31 lean [BMI ≤ 25]). We assessed vaspin and omentin gene expression in paired samples of visceral and subcutaneous abdominal adipose tissue from 46 women: 40 morbidly obese and 6 lean. We determined serum vaspin and plasma omentin levels with an Enzyme-Linked Immunosorbent Assay and adipose tissue mRNA expression by real time RT-PCR. Serum vaspin levels in the morbidly obese were not significantly different from those in controls. They correlated inversely with levels of lipocalin 2 and interleukin 6. Vaspin mRNA expression was significantly higher in the morbidly obese, in both subcutaneous and visceral adipose tissue. Plasma omentin levels were significantly lower in the morbidly obese and they correlated inversely with glucidic metabolism parameters. Omentin circulating levels, then, correlated inversely with the metabolic syndrome (MS). Omentin expression in visceral adipose tissue was significantly lower in morbidly obese women than in controls. The present study indicates that vaspin may have a compensatory role in the underlying inflammation of obesity. Decreased omentin circulating levels have a close association with MS in morbidly obese women.

Stromal stem cells from adipose tissue and bone marrow of age-matched female donors display distinct immunophenotypic profiles.

Abstract: Adipose tissue is composed of lipid-filled mature adipocytes and a heterogeneous stromal vascular fraction (SVF) population of cells. Similarly, the bone marrow (BM) is composed of multiple cell types including adipocytes, hematopoietic, osteoprogenitor, and stromal cells necessary to support hematopoiesis. Both adipose and BM contain a population of mesenchymal stromal/stem cells with the potential to differentiate into multiple lineages, including adipogenic, chondrogenic, and osteogenic cells, depending on the culture conditions. In this study we have shown that human adipose-derived stem cells (ASCs) and bone marrow mesenchymal stem cells (BMSCs) populations display a common expression profile for many surface antigens, including CD29, CD49c, CD147, CD166, and HLA-abc. Nevertheless, significant differences were noted in the expression of CD34 and its related protein, PODXL, CD36, CD 49f, CD106, and CD146. Furthermore, ASCs displayed more pronounced adipogenic differentiation capability relative to BMSC based on Oil Red staining (7-fold vs. 2.85-fold induction). In contrast, no difference between the stem cell types was detected for osteogenic differentiation based on Alizarin Red staining. Analysis by RT-PCR demonstrated that both the ASC and BMSC differentiated adipocytes and osteoblast displayed a significant upregulation of lineage-specific mRNAs relative to the undifferentiated cell populations; no significant differences in fold mRNA induction was noted between ASCs and BMSCs. In conclusion, these results demonstrate human ASCs and BMSCs display distinct immunophenotypes based on surface positivity and expression intensity as well as differences in adipogenic differentiation. The findings support the use of both human ASCs and BMSCs for clinical regenerative medicine.

Multiobjective Model for More Sustainable Fuel Supply Chains. A Case Study of the Sugar Cane Industry in Argentina

Abstract: The objective of this work is to present a quantitative tool to support decision-making in the area of optimal design of supply chains (SC) for the combined production of sugar and ethanol. The problem is formulated as a multiobjective mixed-integer linear program that seeks to optimize simultaneously the economic and environmental performance of the production chain. The advantages of the approach presented are illustrated through its application to a case study, in which a trade-off exists between the economic and environmental performance of the network. Our method provides valuable insight into the problem and a guide to adopt more sustainable strategic alternatives in the design of SCs with embedded biorefineries.

Degradation Effects Related to the Hole Transport Layer in Organic Solar Cells

Abstract: The influence of the hole transport layer on device stability in polymer:fullerene bulk-heterojunction solar cells is reported. Three different hole transport layers varying in composition, dispersion solvent, electrical conductivity, and work function were used in these studies. Two water-based hole transport layers, poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) and polyaniline:poly(styrene sulfonate), and one isopropyl alcohol-based polyaniline:poly(styrene sulfonate) transport layer were investigated. Solar cells with the different hole transport layers were fabricated and degraded under illumination. Current–voltage, capacitance–voltage, and capacitance–frequency data were collected at light intensities of 16, 30, 48, 80, and 100 mW cm−2 over a period of 7 h. Device performance and stability were compared between nonencapsulated and encapsulated samples to gain understanding about degradation effects related to oxygen and water as well as degradation mechanisms related to the intrinsic instability of the solar cell materials and interfaces. It is demonstrated that the properties of the hole transport layer can have a significant impact on the stability of organic solar cells.

Modulatory effect of grape-seed procyanidins on local and systemic inflammation in diet-induced obesity rats

Abstract: Chronic low-grade inflammation in obesity is characterized by macrophage accumulation in white adipose tissue (WAT) and abnormal cytokine production. We tested the hypothesis that grape-seed procyanidin extract (PE), with known anti-inflammatory and antioxidant effects, would improve local and systemic inflammation in diet-induced obesity rats. First, we analyzed the preventive effects of procyanidins (30 mg/kg per day) on rats fed a 60% kcal fat diet for 19 weeks. Second, we induced cafeteria diet obesity for 13 weeks to investigate the corrective effects of two PE doses (25 and 50 mg/kg per day) for 10 and 30 days. In the preventive model, PE group had reduced not only body weight but also plasmatic systemic markers of inflammation tumor necrosis factor-α (TNF-α) and C-reactive protein (CRP). The PE preventive treatment significantly showed an increased adiponectin expression and decreased TNF-α, interleukin-6 and CRP expression in mesenteric WAT and muscle TNF-α. A reduced NF-κB activity in liver is also observed which can be related to low expression rates of hepatic inflammatory markers found in PE group. Finally, PE dietary supplementation is linked to a reduced expression of Emr1 (specific marker of macrophage F4/80), which suggests a reduced macrophage infiltration of WAT. In the corrective model, however, only the high dose of PE reduced CRP plasma levels in the short treatment without changes in plasmatic TNF-α. In conclusion, orally ingested PE helps preventing imbalanced obesity cytokine pattern, but its corrective effects need to be further investigated. The dietary regular intake of food or drinks containing procyanidins might help prevent low-grade inflammatory-related diseases.

Pyranoside phosphite-oxazoline ligands for the highly versatile and enantioselective ir-catalyzed hydrogenation of minimally functionalized olefins. A combined theoretical and experimental study.

Abstract: A modular set of phosphite-oxazoline (P,N) ligands has been applied to the title reaction. Excellent ligands have been identified for a range of substrates, including previously challenging terminally disubstituted olefins, where we now have reached enantioselectivities of 99% for a range of substrates. The selectivity is best for minimally functionalized substrates with at least a moderate size difference between geminal groups. A DFT study has allowed identification of the preferred pathway. Computational prediction of enantioselectivities gave very good accuracy.

On the metric dimension of corona product graphs

Abstract: Given a set of vertices S={v"1,v"2,...,v"k} of a connected graph G, the metric representation of a vertex v of G with respect to S is the vector r(v|S)=(d(v,v"1),d(v,v"2),...,d(v,v"k)), where d(v,v"i), i@?{1,...,k} denotes the distance between v and v"i. S is a resolving set for G if for every pair of distinct vertices u,v of G, r(u|S) r(v|S). The metric dimension of G, dim(G), is the minimum cardinality of any resolving set for G. Let G and H be two graphs of order n"1 and n"2, respectively. The corona product G@?H is defined as the graph obtained from G and H by taking one copy of G and n"1 copies of H and joining by an edge each vertex from the ith-copy of H with the ith-vertex of G. For any integer k>=2, we define the graph G@?^kH recursively from G@?H as G@?^kH=(G@?^k^-^1H)@?H. We give several results on the metric dimension of G@?^kH. For instance, we show that given two connected graphs G and H of order n"1>=2 and n"2>=2, respectively, if the diameter of H is at most two, then dim(G@?^kH)=n"1(n"2+1)^k^-^1dim(H). Moreover, if n"2>=7 and the diameter of H is greater than five or H is a cycle graph, then dim(G@?^kH)=n"1(n"2+1)^k^-^1dim(K"1@?H).

A Chebyshev criterion for Abelian integrals

Abstract: We present a criterion that provides an easy sufficient condition in order for a collection of Abelian integrals to have the Chebyshev property. This condition involves the functions in the integrand of the Abelian integrals and can be checked, in many cases, in a purely algebraic way. By using this criterion, several known results are obtained in a shorter way and some new results, which could not be tackled by the known standard methods, can also be deduced.

Spectrum of Clinically Relevant Acremonium Species in the United States

Abstract: Some species in the polyphyletic fungal genus Acremonium are important opportunist pathogens. Determining the actual spectrum of species and their incidence in the clinical setting, however, has long been hampered because of the difficulties encountered in phenotypic species-level identification. The goal of this study was to re-identify a large number of clinical isolates morphologically and to confirm the identifications by comparing sequences of the internal transcribed spacer region of the rRNA gene of these isolates to those of type or reference strains of well-known Acremonium species. Of the 119 isolates referred to a United States reference laboratory under the name Acremonium, only 75 were identified morphologically as belonging to that genus. The remainder (44 isolates) were identified as belonging to other morphologically similar genera. The Acremonium clinical isolates were related to species of Hypocreales, Sordariales, and of an incertae sedis family of ascomycetes, Plectosphaerellaceae. A total of 50 of the 75 Acremonium isolates (67%) could be identified by molecular means, the prevalent species being Acremonium kiliense (15 isolates), A. sclerotigenum-A. egyptiacum (11 isolates), A. implicatum (7 isolates), A. persicinum (7 isolates), and A. atrogriseum (4 isolates). One of the most interesting findings of our study was that we identified several species among this large collection of clinical isolates that had not previously been reported from human infections, and we failed to confirm other Acremonium species, such as A. potronii, A. recifei, and A. strictum, that had been considered significant. The most common anatomic sites for Acremonium isolates were the respiratory tract (41.3%), nails (10.7%), and the eye (9.3%). Antifungal susceptibility testing demonstrated high MICs for all agents tested, except for terbinafine. Since numerous isolates could not be identified, we concluded that the list of opportunistic Acremonium species is far from be complete and that a considerable number of additional species will be discovered.

Cyclopropanation with Gold(I) Carbenes by Retro-Buchner Reaction from Cycloheptatrienes

Abstract: Cationic gold(I) promotes the retro-Buchner reaction of 7-substituted 1,3,5-cycloheptatrienes, leading to gold(I) carbenes that cyclopropanate alkenes.

FABP 4 is associated with inflammatory markers and metabolic syndrome in morbidly obese women.

Abstract: Objective: The adipocyte/macrophage fatty acid-binding protein 4 (FABP4) has been described as a biomarker for adiposity and metabolic syndrome (MS). The aims of this study were to assess the relationship between FABP4 and inflammatory cytokines related to obesity, and to evaluate FABP4 mRNA expression in visceral and subcutaneous adipose tissue in non-diabetic morbidly obese women versus healthy lean women. Methods: We analyzed circulating levels of FABP4 in 81 Spanish women: 38 lean (body mass index (BMI)!25 kg/m 2 ) and 43 morbidly obese (BMIO40 kg/m 2 ). We took 30 follow-up blood samples at 6 and 12 months after bariatric surgery. We assessed FABP4 gene expression in samples of subcutaneous abdominal and visceral adipose tissue. Adipose tissue mRNA expression was determined by real-time RT-PCR. Results: In morbidly obese women, plasma FABP4 levels were significantly higher than in non-obese patients. These levels positively correlated with BMI, homeostasis model assessment of insulin resistance (HOMA2-IR), and plasma glucose and insulin levels. Post-operative FABP4 levels decreased by a maximum of 30% after 12 months. We also found an inverse association between FABP4 and adiponectin levels, and positive correlations between FABP4 and circulating leptin, tumor necrosis factor (TNF) receptors, C-reactive protein (CRP) and interleukin 6 levels. Linear regression analysis revealed that FABP4 was more closely related to HOMA2-IR than adiponectin, CRP, TNF-RI, or leptin. Furthermore, high circulating FABP4 levels were associated with the presence of MS. FABP4 mRNA expression in visceral adipose tissue was related to its circulating levels in morbidly obese women. Conclusions: Our results indicate that serum FABP4 is associated with inflammatory factors related to obesity and MS in non-diabetic morbidly obese women.

Nonhepatosplenic γδ T-cell lymphomas represent a spectrum of aggressive cytotoxic T-cell lymphomas with a mainly extranodal presentation.

Abstract: γδ T cells represent a minor T-cell subset that is mainly distributed in mucosal surfaces. Two distinct lymphomas derived from these cells have been recognized: hepatosplenic γδ T-cell lymphoma (HSTL) and primary cutaneous γδ T-cell lymphoma (PCGD-TCL). However, whether other anatomic sites may also be involved and whether they represent a spectrum of the same disease are not well studied. The lack of T-cell receptor (TCR)β expression has been used to infer a γδ origin when other methods are not available. We studied 35 T-cell tumors suspected to be γδ TCL using monoclonal antibodies reactive with TCR δ or γ in paraffin sections. We were able to confirm γδ chain expression in 22 of 35 cases. We identified 8 PCGD-TCLs, 6 HSTLs, and 8 γδ TCLs without hepatosplenic or cutaneous involvement involving mainly extranodal sites. Two such cases were classified as enteropathy-associated T-cell lymphoma, type II. The other γδ TCL presented in the intestine, lung, tongue, orbit, and lymph node. In addition, we observed 13 cases with mainly extranodal involvement that lacked any TCR expression ("TCR silent"). In all cases, a natural killer cell origin was excluded. In conclusion, the lack of TCRβ expression does not always predict γδ-T-cell derivation, as TCR silent cases may be found. The recognition of γδ TCL presenting in extranodal sites other than skin and liver/spleen expands the clinical spectrum of these tumors. However, non-HSTL γδ TCL do not seem to represent a single entity. The relationship of these tumors with either HSTL or PCGD-TCL requires further study.

Presence of Pharmaceuticals and Hormones in Waters from Sewage Treatment Plants

Abstract: This paper describes the presence of 33 pharmaceuticals and hormones in waters from two sewage treatment plants (STPs) situated in Catalonia, in northeastern Spain. The target compounds were one psychoactive stimulant, one antiepileptic, four analgesics and non-steroidal anti-inflammatories, one lipid regulators, two anti-ulcer agents, nine antibiotics (sulfonamides and macrolides), two beta-blockers, two metabolites, and 11 hormones (free and conjugates). The determination was performed using liquid chromatography coupled to tandem mass spectrometry after enrichment by solid-phase extraction with Oasis HLB sorbent. Most of the pharmaceuticals were found in both influent and effluent samples from the two STPs. The most frequently detected were caffeine, acetaminophen, carbamazepine, diclofenac, ibuprofen, naproxen, sulfamethoxazole, sulfapyridine, sulfathiazole, ranitidine, omeprazole, estrone 3-sulfate, and estradiol 17-glucuronide. Specifically, the highest concentrations found in influents were 19,850 ng/L (acetaminophen), 9,945 ng/L (caffeine), 4,215 ng/L (ibuprofen), 5,695 ng/L (sulfamethoxazole), and 5,140 ng/L (sulfathiazole). Most of the pharmaceuticals present in influent waters were found in effluents at lower concentrations. The highest concentrations in effluents were 970 ng/L (caffeine), 670 ng/L (sulfamethoxazole), 510 ng/L (bezafibrate), and 1,032 ng/L (diclofenac).

The Shape of the Sc2(μ2-S) Unit Trapped in C82: Crystallographic, Computational, and Electrochemical Studies of the Isomers, Sc2(μ2-S)@Cs(6)-C82 and Sc2(μ2-S)@C3v(8)-C82

Abstract: Single-crystal X-ray diffraction studies of Sc2(μ2-S)@Cs(6)-C82·NiII(OEP)·2C6H6 and Sc2(μ2-S)@C3v(8)-C82·NiII(OEP)·2C6H6 reveal that both contain fully ordered fullerene cages. The crystallographic data for Sc2(μ2-S)@Cs(6)-C82·NiII(OEP)·2C6H6 show two remarkable features: the presence of two slightly different cage sites and a fully ordered molecule Sc2(μ2-S)@Cs(6)-C82 in one of these sites. The Sc−S−Sc angles in Sc2(μ2-S)@Cs(6)-C82 (113.84(3)°) and Sc2(μ2-S)@C3v(8)-C82 differ (97.34(13)°). This is the first case where the nature and structure of the fullerene cage isomer exerts a demonstrable effect on the geometry of the cluster contained within. Computational studies have shown that, among the nine isomers that follow the isolated pentagon rule for C82, the cage stability changes markedly between 0 and 250 K, but the Cs(6)-C82 cage is preferred at temperatures ≥250 °C when using the energies obtained with the free encapsulated model (FEM). However, the C3v(8)-C82 cage is preferred at temperatures ≥250 ...

Itinerários terapêuticos: o estado da arte da produção científica no Brasil

Abstract: Knowledge about the itineraries of people seeking healthcare may contribute to our understanding of behavior in relation to healthcare and utilization of health services. In Brazil, however, despite their relevance there have been few studies into healthcare-seeking behavior and those available are relatively new and have not received the attention they deserve from health researchers and managers. This article presents the results of a survey of the Brazilian scientific literature on this subject published in the past 20 years, describing and analyzing the approaches used. Data were collected between September and November 2008 through the portal of the Virtual Health Library. The search located 11 articles and content analysis was used to generate categories. The majority of these studies are grounded in socio-anthropological theory, and the main focus of interest is the patient's perception of disease and treatment. Only a few of these publications address patients' access to and utilization of health services. It is argued that the study of healthcare-seeking behavior can be an important tool for improving the quality of healthcare.

Actitudes y expectativas del uso educativo de las redes sociales en los alumnos universitarios

Abstract: Normal 0 21 false false false CA X-NONE X-NONE /* Style Definitions */ tableMsoNormalTable {mso-style-name:"Tabla normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0pt 54pt 0pt 54pt; mso-para-margin-top:0pt; mso-para-margin-right:0pt; mso-para-margin-bottom:100pt; mso-para-margin-left:0pt; line-height:115%; mso-pagination:widow-orphan; font-size:110pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin;} Les xarxes socials, que els ultims anys han comportat una autentica revolucio en la manera de relacionar-se, encara continuen essent poc presents en l'ambit academic: les ocasions en que es fan servir son aillades i poques tenen continuitat En aquest context, volem reflexionar sobre l'actitud que els mateixos estudiants tenen envers l'us, l'aprofitament didactic i les potencialitats que les xarxes socials presenten en l'ambit educatiu Per a aquesta reflexio ens hem valgut d'una enquesta feta entre els estudiants La intencio es que l'estudi d'aquesta actitud inicial sigui el pas previ necessari per a trobar les claus perque l'alumnat accepti i materialitzi el potencial educatiu de les xarxes socials