Tunneling spectra of layered strongly correlated d-wave superconductors

Tunneling conductance experiments on cuprate superconductors exhibit a large diversity of spectra that appear in different nano-sized regions of inhomogeneous samples. In this letter, we use a mean-field approach to the tt't''J model in order to address the features in these spectra that deviate from the BCS paradigm, namely, the bias sign asymmetry at high bias, the generic lack of evidence for the Van Hove singularity, and the occasional absence of coherence peaks. We conclude that these features can be reproduced in homogeneous layered d-wave superconductors solely due to a proximate Mott insulating transition. We also establish the connection between the above tunneling spectral features and the strong renormalization of the electron dispersion around (0,pi) and (pi,0) and the momentum space anisotropy of electronic states observed in ARPES experiments.Comment: 4 pages, 3 figures. Added comment on the role of sample inhomogeneity. Published version. Homepage http://dao.mit.edu/~wen

Electromagnetic response of high-Tc superconductors -- the slave-boson and doped-carrier theories

We evaluate the doping dependence of the quasiparticle current and low temperature superfluid density in two slave-particle theories of the tt't''J model -- the slave-boson theory and doped-carrier theory. In the slave-boson theory, the nodal quasiparticle current renormalization factor $\alpha$ vanishes proportionally to the zero temperature superfluid density $\rho_S(0)$; however, we find that away from the $\rho_S(0) \to 0$ limit $\alpha$ displays a much weaker doping dependence than $\rho_S(0)$. A similar conclusion applies to the doped-carrier theory, which differentiates the nodal and antinodal regions of momentum space. Due to its momentum space anisotropy, the doped-carrier theory enhances the value of $\alpha$ in the hole doped regime, bringing it to quantitative agreement with experiments, and reproduces the asymmetry between hole and electron doped cuprate superconductors. Finally, we use the doped-carrier theory to predict a specific experimental signature of local staggered spin correlations in doped Mott insulator superconductors which, we propose, should be observed in STM measurements of underdoped high-Tc compounds. This experimental signature distinguishes the doped-carrier theory from other candidate mean-field theories of high-Tc superconductors, like the slave-boson theory and the conventional BCS theory.Comment: 12 pages, RevTeX4, homepage http://dao.mit.edu/~we

Doped carrier formulation and mean-field theory of the tt't''J model

In the generalized-tJ model the effect of the large local Coulomb repulsion is accounted for by restricting the Hilbert space to states with at most one electron per site. In this case the electronic system can be viewed in terms of holes hopping in a lattice of correlated spins, where holes are the carriers doped into the half-filled Mott insulator. To explicitly capture the interplay between the hole dynamics and local spin correlations we derive a new formulation of the generalized-tJ model where doped carrier operators are used instead of the original electron operators. This ``doped carrier'' formulation provides a new starting point to address doped spin systems and we use it to develop a new, fully fermionic, mean-field description of doped Mott insulators This mean-field approach reveals a new mechanism for superconductivity, namely spinon-dopon mixing, and we apply it to the tt't''J model as of interest to high-temperature superconductors. In particular, we use model parameters borrowed from band calculations and from fitting ARPES data to obtain a mean-field phase diagram that reproduces semi-quantitatively that of hole and electron doped cuprates. The mean-field approach hereby presented accounts for the local antiferromagnetic and d-wave superconducting correlations which, we show, provide a rational for the role of t' and t'' in strengthening superconductivity as expected by experiments and other theoretical approaches. As we discuss how t, t' and t'' affect the phase diagram, we also comment on possible scenarios to understand the differences between as-grown and oxygen reduced electron doped samples.Comment: 17 pages, 2 figures. Homepage http://dao.mit.edu/~wen

Support for automatic refactoring of business logic

Software’s structure profoundly affects its development and maintenance costs. Poor software’s structure may lead to well-known design flaws, such as large modules or long methods. A possible ap- proach to reduce a module’s complexity is the Extract Method refactor- ing technique. This technique allows the decomposition of a large and complex method into smaller and simpler ones, while reducing the orig- inal method’s size and improving its readability and comprehension. The OutSystems platform is a low-code platform that allows the de- velopment of web and mobile applications that rely on a set of visual Domain-Specific Languages (DSLs). Even low-code languages when im- properly used can lead to software that has maintenance issues like long methods. Thus, the purpose of this paper is to present the research and devel- opment done to provide the OutSystems platform with a tool that au- tomatically suggests Extract Method refactoring opportunities. The re- search combines program slicing techniques with code complexity metrics to calculate the best refactoring opportunities that preserve programs’ functionality. The proposed approach was tested on typical OutSystems apps and was shown to be able to reduce the overall applications’ complexity.info:eu-repo/semantics/publishedVersio

Satisfação dos utentes com o atendimento prestado nas farmácias comunitárias

A satisfação dos utentes é considerada uma medida importante com efeitos nos resultados de cuidados de saúde. Objetivos: Determinar o grau de satisfação dos utentes com o atendimento nas farmácias comunitárias, e verificar se o grau de satisfação é igual, independentemente, da idade e do género do utente. Material e Métodos: Este estudo de caracter transversal, observacional e correlacional teve como base uma amostra não probabilística acidental, constituída por 525 inquiridos. O questionário foi aplicado no período de Outubro de 2012 a Janeiro de 2013 em quatro localidades seleccionadas por conveniência na zona norte de Portugal, foi utilizada a escala “Pharmacy Services Questionnaire” (FSQ) validada para a língua portuguesa, desenvolvida por Larson et al. (2002). Em relação ao género dos inquiridos, verificou-se que 60,62% pertenciam ao sexo feminino e 39,38% eram do sexo masculino. Com idades compreendidas entre os 18 e os 83 anos, com uma média de 41,81 anos (D.P.±16,262, o que permite concluir que a amostra não é homogénea relativamente à idade). Em relação à escolaridade dos inquiridos, 2,9% não possuíam estudos; 16,8% tinham entre 1 a 4 anos de escolaridade; 9,5% possuíam o 2º ciclo; 12,4% possuíam o 3º ciclo; 31,6% concluíram o ensino secundário e 23,2% possuíam habilitações superiores. Resultados: Os indicadores de validade da análise fatorial mostraram um KMO=0,972. Foram identificados duas dimensões, nomeadamente, o atendimento e acompanhamento farmacoterapêutico, que explicavam no conjunto 64,230% da variância total. O Alfa Cronbach total foi de 0,962, o que indica uma fiabilidade da consistência interna muito boa. A contribuição das dimensões para a satisfação global dos utentes foi por ordem de importância, o atendimento (r=0,864; p<0,01) e acompanhamento farmacoterapêutico (r=0,848; p<0,01). O grau de satisfação dos utentes com os serviços das farmácias comunitárias foi o seguinte: reduzido para 5,3%, médio para 39%, bom para 46,1% e muito bom para 9%. Tendo em conta o fator atendimento por género, o feminino registou um grau de satisfação mais elevado, enquanto que, no fator acompanhamento farmacoterapêutico não se verificou qualquer diferença entre géneros. Relativamente à classe etária, verificou-se que são os utentes com idades mais avançadas, que registam um grau de satisfação mais elevado. Discussão e Conclusão: Concluiu-se que, de um modo geral, os utentes se encontram satisfeitos com o atendimento nas farmácias comunitárias, sendo o sexo feminino e os utentes com idades mais avançadas, os que apresentam um grau de satisfação superior. O aspeto a melhorar para o aumento da satisfação dos utentes, relativamente ao acompanhamento farmacoterapêutico, é “O modo como o profissional de farmácia lhe explica os possíveis efeitos secundários”. Em relação ao atendimento o aspeto a melhorar é “O modo como o profissional de farmácia responde às suas perguntas”

Users satisfaction regarding the service provided in community pharmacies

During the last century, the pharmacy professionals have significantly being professionalized, the user is a high priority and not just limited to the sale of pharmaceuticals. As such, it is necessary to know the users, their needs and expectations, their opinions and preferences. This transversal study, observational, correlational, aimed to: determine the degree of satisfaction with the attendance in community pharmacies, if there is a relationship between factors of a personal nature (age and gender) and satisfaction, trying to identify which aspects improve in order to increase satisfaction levels. The sample consisted of 525 respondents. Data collection was conducted in the period from October 2012 to January 2013 in four locations in northern Portugal. It was used a questionnaire consisting of three parts: the first contained items of personal characterization, the second consisted of the scale "Pharmacy Services Questionnaire" (FSQ) validated for the Portuguese language, developed by Larson et al. (2002) and the last had questions about the respondents' opinion. The results showed that the degree of satisfaction with the services of community pharmacies was in majority an average to 39 % and good for 46,1% . Having in mind the factor by gender, females showed a higher degree of satisfaction. Regarding the age group, older users had the highest degree of satisfaction. It was concluded that, generally, community pharmacies bring a higher degree of satisfaction in the older and the female users. "How the pharmacy professionals explain possible side effects" and "how the pharmacy professional answers your questions.", are the two aspects that must be improved to achieve a higher degree of satisfaction. KEYWORDS Satisfaction, Users, Customer Service, Pharmacotherapy Monitoring, Community Pharmacie

Primary metabolite profile changes in coffea spp. Promoted by single and combined exposure to drought and elevated co2 concentration

info:eu-repo/grantAgreement/FCT/OE/PD%2FBD%2F113475%2F2015/PT PD/00035/2013 CRA-RED-00053-16Climate change scenarios pose major threats to many crops worldwide, including coffee. We explored the primary metabolite responses in two Coffea genotypes, C. canephora cv. Conilon Clone 153 and C. arabica cv. Icatu, grown at normal (aCO2) or elevated (eCO2) CO2 concentrations of 380 or 700 ppm, respectively, under well-watered (WW), moderate (MWD), or severe (SWD) water deficit conditions, in order to assess coffee responses to drought and how eCO2 can influence such responses. Primary metabolites were analyzed with a gas chromatography time-of-flight mass spectrometry metabolomics platform (GC-TOF-MS). A total of 48 primary metabolites were identified in both genotypes (23 amino acids and derivatives, 10 organic acids, 11 sugars, and 4 other metabolites), with differences recorded in both genotypes. Increased metabolite levels were observed in CL153 plants under single and combined conditions of aCO2 and drought (MWD and SWD), as opposed to the observed decreased levels under eCO2 in both drought conditions. In contrast, Icatu showed minor differences under MWD, and increased levels (especially amino acids) only under SWD at both CO2 concentration conditions, although with a tendency towards greater increases under eCO2. Altogether, CL153 demonstrated large impact under MWD, and seemed not to benefit from eCO2 in either MWD and SWD, in contrast with Icatu.publishersversionpublishe

The narrative model of therapeutic change: an exploratory study tracking innovative moments and protonarratives using state space grids

Despite the popularity of narrative approaches to the change in psychotherapy, a better understanding of how narrative transformation facilitates therapeutic change is needed. Research on innovative moments (IMs) has explored how IMs in psychotherapy evolve over time. We expand on past studies by exploring how IMs become aggregated in narrative threads, termed protonarratives, which come to constitute an alternative self-narrative at the conclusion of therapy. The results suggest that the good outcome case had a different pattern of IM integration within protonarratives, revealing greater flexibility than the poor outcome case. These results support the heuristic value of the concept of the protonarrative

Actinobacteria Isolated From Laminaria ochroleuca: A Source of New Bioactive Compounds

Nature is the major reservoir of biologically active molecules. The urgent need of finding novel molecules for pharmaceutical application is prompting the research of underexplored environments, such as marine ecosystems. Here, we investigated cultivable actinobacteria associated with the macroalgae Laminaria ochroleuca and assessed their potential to produce compounds with antimicrobial or anticancer activities. A specimen of L. ochroleuca was collected in a rocky shore in northern Portugal, and fragments of tissues from different parts of the macroalgae (holdfast, stipe, and blades) were surface sterilized and plated in three culture media selective for actinobacteria. A total of 90 actinobacterial strains were isolated, most of which affiliated with the genus Streptomyces. Isolates associated with the genera Isoptericola, Rhodococcus, Nonomuraeae, Nocardiopsis, Microbispora, and Microbacterium were also obtained. Organic extracts from the isolates were tested for their antimicrobial activity using the agar-based disk diffusion method, followed by determination of minimum inhibitory concentration (MIC) values. Forty-five isolates inhibited the growth of Candida albicans and/or Staphylococcus aureus, with MIC values ranging from &lt;0.5 to 1000 μg mL−1. The actinobacterial isolates were also tested for their anticancer potential on two human cancer cell lines. Twenty-eight extracts affected the viability of at least one human cancer cell line (breast carcinoma T-47D and neuroblastoma SH-SY5Y) and non-carcinogenic endothelial cell line (hCMEC/D3). Seven extracts affected the viability of cancer cells only. This study revealed that L. ochroleuca is a rich source of actinobacteria with promising antimicrobial and anticancer activities and suggests that macroalgae may be a valuable source of actinobacteria and, consequently, of new molecules with biotechnological importance