High temperature ferromagnetism of Li-doped vanadium oxide nanotubes

The nature of a puzzling high temperature ferromagnetism of doped mixed-valent vanadium oxide nanotubes reported earlier by Krusin-Elbaum et al., Nature 431 (2004) 672, has been addressed by static magnetization, muon spin relaxation, nuclear magnetic and electron spin resonance spectroscopy techniques. A precise control of the charge doping was achieved by electrochemical Li intercalation. We find that it provides excess electrons, thereby increasing the number of interacting magnetic vanadium sites, and, at a certain doping level, yields a ferromagnetic-like response persisting up to room temperature. Thus we confirm the surprising previous results on the samples prepared by a completely different intercalation method. Moreover our spectroscopic data provide first ample evidence for the bulk nature of the effect. In particular, they enable a conclusion that the Li nucleates superparamagnetic nanosize spin clusters around the intercalation site which are responsible for the unusual high temperature ferromagnetism of vanadium oxide nanotubes.Comment: with some amendments published in Europhysics Letters (EPL) 88 (2009) 57002; http://epljournal.edpsciences.or

Magnetic properties of the low-dimensional spin-1/2 magnet \alpha-Cu_2As_2O_7

In this work we study the interplay between the crystal structure and magnetism of the pyroarsenate \alpha-Cu_2As_2O_7 by means of magnetization, heat capacity, electron spin resonance and nuclear magnetic resonance measurements as well as density functional theory (DFT) calculations and quantum Monte Carlo (QMC) simulations. The data reveal that the magnetic Cu-O chains in the crystal structure represent a realization of a quasi-one dimensional (1D) coupled alternating spin-1/2 Heisenberg chain model with relevant pathways through non-magnetic AsO_4 tetrahedra. Owing to residual 3D interactions antiferromagnetic long range ordering at T_N\simeq10K takes place. Application of external magnetic field B along the magnetically easy axis induces the transition to a spin-flop phase at B_{SF}~1.7T (2K). The experimental data suggest that substantial quantum spin fluctuations take place at low magnetic fields in the ordered state. DFT calculations confirm the quasi-one-dimensional nature of the spin lattice, with the leading coupling J_1 within the structural dimers. QMC fits to the magnetic susceptibility evaluate J_1=164K, the weaker intrachain coupling J'_1/J_1 = 0.55, and the effective interchain coupling J_{ic1}/J_1 = 0.20.Comment: Accepted for publication in Physical Review

Bayesian hierarchical clustering for studying cancer gene expression data with unknown statistics

Clustering analysis is an important tool in studying gene expression data. The Bayesian hierarchical clustering (BHC) algorithm can automatically infer the number of clusters and uses Bayesian model selection to improve clustering quality. In this paper, we present an extension of the BHC algorithm. Our Gaussian BHC (GBHC) algorithm represents data as a mixture of Gaussian distributions. It uses normal-gamma distribution as a conjugate prior on the mean and precision of each of the Gaussian components. We tested GBHC over 11 cancer and 3 synthetic datasets. The results on cancer datasets show that in sample clustering, GBHC on average produces a clustering partition that is more concordant with the ground truth than those obtained from other commonly used algorithms. Furthermore, GBHC frequently infers the number of clusters that is often close to the ground truth. In gene clustering, GBHC also produces a clustering partition that is more biologically plausible than several other state-of-the-art methods. This suggests GBHC as an alternative tool for studying gene expression data. The implementation of GBHC is available at https://sites. google.com/site/gaussianbhc

Cloning, in silico structural characterization and expression analysis of MfAtr4, an ABC transporter from the banana pathogen Mycosphaerella fijiensis

ABC transporters are membrane proteins that use the energy released from the hydrolysis of ATP to drive the transport of compounds across biological membranes. In some plants, pathogenic fungi ABC transporters play a role as virulence factors by mediating the export of plant defense compounds or fungal virulence factors. Mycosphaerella fijiensis, the causal agent of black Sigatoka disease in banana, is the main constraint for the banana industry worldwide. So far, little is known about molecular mechanism that it uses to infect the host. In this study, degenerated primers designed from fungal ABC transporters known to be involved in virulence were used to isolate homologs from M. fijiensis. Here, we reported the full cloning of MfAtr4 a putative ortholog of MgAtr4, an ABC transporter of the related Mycosphaerella graminicola with a function in virulence. Similarities and differences with its presumed ortholog MgAtr4 are described, and the putative function of MfAtr4 are discussed. Analysis of MfAtr4 gene expression in field banana samples exhibiting visible symptoms of black Sigatoka disease indicated a higher expression of MfAtr4 during the first symptomatic stages in comparison to the late necrotrophic phases, suggesting a role for MfAtr4 in the early stages of pathogenic development of M. fijiensis.Key words: ABC transporters, virulence factors, MgAtr4 ortholog, Mycosphaerella fijiensis, black Sigatoka, Musa sp

Modified Wisconsin Card Sorting Test (M-WCST): Normative data for Spanish-speaking pediatric population

OBJECTIVE: To generate normative data for the Modified Wisconsin Card Sorting Test (M-WCST) in Spanish-speaking pediatric populations. METHOD: The sample consisted of 4,373 healthy children from nine countries in Latin America (Chile, Cuba, Ecuador, Guatemala, Honduras, Mexico, Paraguay, Peru, and Puerto Rico) and Spain. Each participant was administered the M-WCST as part of a larger neuropsychological battery. Number of categories, perseverative errors, and total error scores were normed using multiple linear regressions and standard deviations of residual values. Age, age2, sex, and mean level of parental education (MLPE) were included as predictors in the analyses. RESULTS: The final multiple linear regression models indicated main effects for age on all scores, such that the number of categories correct increased and total number of perseverative errors and total number of errors decrease linearly as a function of age. Age2 had a significant effect in Chile, Cuba, Ecuador, and Spain for numbers of categories; a significant effect for number of perseverative errors in Chile, Cuba, Mexico, and Spain; and a significant effect for number of total errors in Chile, Cuba, Peru, and Spain. Models showed an effect for MLPE in Cuba (total errors), Ecuador (categories and total errors), Mexico (all scores), Paraguay (perseverative errors and total error), and Spain (categories and total errors). Sex affected number of total errors for Ecuador. CONCLUSIONS: This is the largest Spanish-speaking pediatric normative study in the world, and it will allow neuropsychologists from these countries to have a more accurate way to interpret the M-WCST with pediatric populations

Theory of Mind and social functioning among neuropsychiatric disorders:A transdiagnostic study

Social dysfunction is commonly present in neuropsychiatric disorders of schizophrenia (SZ) and Alzheimer's disease (AD). Theory of Mind (ToM) deficits have been linked to social dysfunction in disease-specific studies. Nevertheless, it remains unclear how ToM is related to social functioning across these disorders, and which factors contribute to this relationship. We investigated transdiagnostic associations between ToM and social functioning among SZ/AD patients and healthy controls, and explored to what extent these associations relate to information processing speed or facial emotion recognition capacity. A total of 163 participants were included (SZ: n=56, AD: n=50 and age-matched controls: n=57). Social functioning was assessed with the Social Functioning Scale (SFS) and the De Jong-Gierveld Loneliness Scale (LON). ToM was measured with the Hinting Task. Information processing speed was measured by the Digit Symbol Substitution Test (DSST) and facial emotion recognition capacity by the facial emotion recognition task (FERT). Case-control deficits in Hinting Task performance were larger in AD (rrb = -0.57) compared to SZ (rrb = -0.35). Poorer Hinting Task performance was transdiagnostically associated with the SFS (βHinting-Task = 1.20, p<0.01) and LON (βHinting-Task = -0.27, p<0.05). DSST, but not FERT, reduced the association between the SFS and Hinting Task performance, however the association remained significant (βHinting-Task = 0.95, p<0.05). DSST and FERT performances did not change the association between LON and Hinting Task performance. Taken together, ToM deficits are transdiagnostically associated with social dysfunction and this is partly related to reduced information processing speed

Effectiveness and safety of once-weekly semaglutide: findings from the SEMACOL-REAL retrospective multicentric observational study in Colombia

IntroductionDiabetes stands as one of the leading causes of death worldwide. Glucagon-like peptide-1 receptor agonists rank among the most effective medications for lowering blood glucose and body weight, as well as reducing cardiovascular risk in individuals with diabetes. Observational studies complement experimental evidence in new settings, different populations, and real-world healthcare practices.MethodsA multicentric observational study of adults with type 2 diabetes treated with once-weekly subcutaneous semaglutide in four health centers in Colombia was conducted. The protocol for the present study was not pre-registered.ResultsData from 186 patients were included. Most patients were women (57%) with a mean age of 62.8 ± 12.1 years. One year of once-weekly semaglutide usage was associated with a mean reduction in HbA1C of −1.47% (95% CI −1.76, −1.17), weight loss of −4.23 kg (95% CI −5.34, −3.12), and albumin/creatinine ratio of −18.6 mg/g (95% CI −60.2, −5.9). Approximately half the treated patients achieved a level of HbA1c ≤7% by the end of follow-up. Adverse events were rare and consistent with clinical trial safety profiles.ConclusionIn Colombia, administering semaglutide subcutaneously once a week over a 1-year period led to an average weight loss of 4.2 kg and a decrease of 1.4% in HbA1c

Towards interoperability through inter-enterprise collaboration architectures

Most enterprise architectures published so far are capable of generating reasonably good descriptive models for individual enterprises to enable integration, organization and synchronization of enterprise elements: organizational structure, business processes, information systems and technology infrastructure, among others. However, research in this field applied to the extended enterprise or inter-enterprise architectures that takes into account the growing trend towards complex collaborative environments is very scarce. In this sense, this article seeks to analyze, link and synthesize the researches that has addressed the disciplines of enterprise architecture and business collaboration, in order to identify possible future research needs from the conceptualization made.Vargas, A.; Boza Garcia, A.; Cuenca, L. (2011). Towards interoperability through inter-enterprise collaboration architectures. En On the Move to Meaningful Internet Systems: OTM 2011 Workshops. Springer Verlag (Germany). 7046:102-111. doi:10.1007/978-3-642-25126-9_18S1021117046Adam, O., Hofer, A., Zang, S., Hammer, C., Jerrentrup, M., Leinenbach, S.: A Collaboration Framework for Cross-enterprise Business Process Management. In: First International Conference on Interoperability of Enterprise Software and Application, Geneva (2005)Chalmeta, R., Grangel, R.: ARDIN extension for virtual enterprise integration. The Journal of Systems and Software 67, 141–152 (2003)Choi, Y., Kang, D., Chae, H., Kim, K.: An enterprise architecture framework for collaboration of virtual enterprise chains. The International Journal of Advanced Manufacturing Technology 35, 1065–1078 (2008)Schekkerman, J.: Extended Enterprise Architecture Framework Essentials Guide. Institute For Enterprise Architecture Developments, IFEAD (2006), http://www.enterprise-architecture.info/index.htmISO 15704. Industrial automation systems - Requirements for enterprise-reference architectures and methodologies.: International Organization for Standardization (2000)Kosanke, K., Vernadat, F., Zelm, M.: CIMOSA: Enterprise engineering and integration. Computers in Industry 40, 83–97 (1999)Cuenca, L.: Marco arquitectónico para la propuesta IE-GIP. Extensión de la arquitectura CIMOSA. Aplicación a una empresa del sector cerámico. PhD thesis. Universidad Politécnica de ValenciaMolina, A., Panetto, H., Chen, D., Whitman, L.: Enterprise Integration and Networking: challenges and trends. Studies in Informatics and Control 16(4), 353–368 (2007)Ortiz, A., Lario, F., Ros, L.: Enterprise Integration—Business Processes Integrated Management: a proposal for a methodology to develop Enterprise Integration Programs. Computers in Industry 40, 155–171 (1999)Chalmeta, R., Campos, C., Grangel, R.: References architectures for enterprise integration. The Journal of Systems and Software 57, 175–191 (2001)Vernadat, F.: Enterprise modeling and integration (EMI): Current status and research perspectives. Annual Reviews in Control 26, 15–25 (2002)Williams, T., Li, H.: PERA and GERAM enterprise reference architectures in enterprise integration. Information Infrastructure Systems for Manufacturing, 1–27 (1998)Lankhorst, M.: Enterprise Architecture at Work: Modelling, Communication and Analysis. Springer, Heidelberg (2009)Arango, M., Londoño, J., Zapata, J.: Arquitectura empresarial- Una visión general. Revista Ingenierías Universidad de Medellín 9(16), 101–111 (2010)Bernard, S.: An introduction to enterprise architecture. AuthorHouse, Bloomington (2005)Cuenca, L., Ortiz, A., Boza, A.: Arquitectura de Empresa. Visión General. In: IX Congreso de Ingeniería de Organización, Gijón (2005)Maya, E.: Arquitectura empresarial: un nuevo reto para las empresas de hoy. Centro de Investigación de las Telecomunicaciones. INTERACTIC: Interacción con la información (2010), http://www.interactic.org.co/THE OPEN GROUP.: ARCHIMATE, The Power of Enterprise Architecture (2009), http://www.archimate.org/en/home/Stelzer, D.: Enterprise Architecture Principles: Literature Review and Research Directions. In: Dan, A., Gittler, F., Toumani, F. (eds.) ICSOC/ServiceWave 2009. LNCS, vol. 6275, pp. 12–21. Springer, Heidelberg (2010)Schekkerman, J.: Enterprise architecture validation. Achieving business-aligned and validated enterprise architectures. Institute For Enterprise Architecture Developments, IFEAD (2004), http://www.enterprise-architecture.info/index.htmKosanke, K.: CIMOSA Primer on key concepts, purpose and business value (1996), http://cimosa.cnt.pl/Chen, D., Vallespir, B., Doumeingts, G.: GRAI integrated methodology and its mapping onto generic enterprise reference architecture and methodology. Computers in Industry 33, 387–394 (1997)Rathwell, G.: PERA Enterprise Integration Web Site (2005), http://www.pera.net/Williams, T., Rathwell, G., Li, H.: A handbook on master planning and implementation for enterprise integration programs. PERA Enterprise Integration Web Site (2001), http://www.pera.net/IFIP.: GERAM: Generalised Enterprise Reference Architecture and Methodology. International Federation for Information Processing (1999), http://dl.ifip.org/index.php/index/indexOrtiz, A.: Propuesta para el Desarrollo de Programas de Integración Empresarial en Empresas Industriales. Aplicación a una Empresa del Sector Cerámico. Universidad Politécnica de Valencia (1998)Cuenca, L., Boza, A., Ortiz, A.: Architecting business and IS/IT strategic alignment for extend enterprises. Studies in Informatics and Control 20(1), 7–18 (2011)The Open Group (2011), https://www.opengroup.org/index.htmGrangel, R.: Propuesta para el Modelado del Conocimiento Empresarial. PhD thesis Universidad Jaume I de Castello (2007)Scheer, A., Schneider, K.: ARIS – Architecture of Integrated Information. Handbook on Architectures of Information Systems. International Handbooks on Information Systems 3, 605–623 (2006)ISO/CEN 19439. Enterprise integration - Framework for enterprise modelling.: International Organization for Standardization (2006)Stadtler, H., Kilger, C.: Supply Chain Management and advance planning. Concepts, Models, Sofware and Cases Studies. Springer, Heidelberg (2002)Alarcón, F., Ortiz, A., Alemany, M., Lario, F.: Planificación Colaborativa en un contexto de varias Cadenas de Suministro: ventajas y desventajas. In: VIII Congreso de Ingeniería de Organización, Leganés, pp. 857–866 (2004)Alarcón, F.: Desarrollo de una Arquitectura para la definición del proceso de Comprometer Pedidos en contextos de Redes de Suministro Colaborativas. Aplicación a una Red compuesta por Cadenas de Suministro en los Sectores Cerámico y del Mueble. PhD thesis Universidad Politécnica de Valencia (2005)Petersen, K., Ragatz, G., Monczka, R.: An Examination of Collaborative Planning Effectiveness and Supply Chain Performance. The Journal of Supply Chain Management 41(2), 14–25 (2005)Ribas, I., Companys, R.: Estado del arte de la planificación colaborativa en la cadena de suministro: Contexto determinista e incierto. Intangible Capital, 91–121 (2007)Ribas, I., Lario, F., Companys, R.: Modelos para la planificación colaborativa en la cadena de suministro: contexto determinista e incierto. In: Congreso de ingeniería de organización, Valencia, pp. 1–10 (2006)Dudek, G.: Collaborative Planning in Supply Chains. Supply Chain Management and Collaborative Planning. Springer, Heidelberg (2009)Stadtler, H.: A framework for collaborative planning and state-of-the-art. OR Spectrum 31, 5–30 (2009)Kilger, C., Reuter, B., Stadtler, H.: Collaborative Planning. In: Stadtler, H., Kilger, C. (eds.) Supply Chain Management and Advanced Planning-—Concepts, Models Software and Case Studies, pp. 263–284. Springer, Heidelberg (2008)Audy, J., Lehoux, N., D’Amours, S.: A framework for an efficient implementation of logistics collaborations. International Transactions in Operational Research, 1–25 (2010)Zachman, J.: A Framework for Information Systems Architecture. IBM Systems Journal 26(3), 454–470 (1987

c-Myc overexpression sensitises colon cancer cells to camptothecin-induced apoptosis

The proto-oncogene c-Myc is overexpressed in 70% of colorectal tumours and can modulate proliferation and apoptosis after cytotoxic insult. Using an isogenic cell system, we demonstrate that c-Myc overexpression in colon carcinoma LoVo cells resulted in sensitisation to camptothecin-induced apoptosis, thus identifying c-Myc as a potential marker predicting response of colorectal tumour cells to camptothecin. Both camptothecin exposure and c-Myc overexpression in LoVo cells resulted in elevation of p53 protein levels, suggesting a role of p53 in the c-Myc-imposed sensitisation to the apoptotic effects of camptothecin. This was confirmed by the ability of PFT-alpha, a specific inhibitor of p53, to attenuate camptothecin-induced apoptosis. p53 can induce the expression of p21(Waf1/Cip1), an antiproliferative protein that can facilitate DNA repair and drug resistance. Importantly, although camptothecin treatment markedly increased p21(Waf1/Cip1) levels in parental LoVo cells, this effect was abrogated in c-Myc-overexpressing derivatives. Targeted inactivation of p21(Waf1/Cip1) in HCT116 colon cancer cells resulted in significantly increased levels of apoptosis following treatment with camptothecin, demonstrating the importance of p21(Waf1/Cip1) in the response to this agent. Finally, cDNA microarray analysis was used to identify genes that are modulated in expression by c-Myc upregulation that could serve as additional markers predicting response to camptothecin. Thirty-four sequences were altered in expression over four-fold in two isogenic c-Myc-overexpressing clones compared to parental LoVo cells. Moreover, the expression of 10 of these genes was confirmed to be significantly correlated with response to camptothecin in a panel of 30 colorectal cancer cell lines