Dual interacting cosmologies and late accelerated expansion

In this paper we show that by considering a universe dominated by two interacting components a superaccelerated expansion can be obtained from a decelerated one by applying a dual transformation that leaves the Einstein's field equations invariant.Comment: 13 pages, 1 figura, version to match published articl

Interdisciplinary programs evaluation methods: a review of literature and a model proposal for intensive projects involving academia and industry

The technological evolution occurred in the last twenty years led organizations to a different global business environment requiring them to be increasingly effective and competitive, implying changes in the way they work. The new paradigm focuses on interdisciplinary team work and so it is required from engineering graduates to have higher levels of transversal competences, like interpersonal communication and team work skills as well as to be able to solve complex engineering problems, in some situations involving areas outside engineers’ common initial training. These changes have clear implications in engineering education and in order to improve engineering education curricula, initiatives like multi and interdisciplinary programs have been implemented in Engineering Schools, with aim to improve the interaction between academia and business companies with win‐win relations. Some of these projects are intensively developed during a short period of time, at the company’s facilities. Along with these initiatives emerges the need to evaluate them. According to the literature, there is a lack of systematic evaluation systems of these projects, so the aim of the paper is to suggest an approach to evaluate interdisciplinary intensive projects, focusing on the competences required by the organizations and considering projects’ stakeholders – participants, tutors, company representatives and educational institutions. The methodology used is based on a literature review of topics related to Project‐Based Learning, aiming to develop a systematic evaluation method that will involve the following dimensions: required outcomes for the participants, competences assessment methods and benefits for stakeholders who participate.This work was partially funded by the Portuguese Foundation for Science and Technology (FCT ‐ Fundação para a Ciência e Tecnologia) with the following project PEST‐OE/EME/UI0252/2011

Weed Diversity Affects Soybean and Maize Yield in a Long Term Experiment in Michigan, USA

Managing production environments in ways that promote weed community diversity may enhance both crop production and the development of a more sustainable agriculture. This study analyzed data of productivity of maize (corn) and soybean in plots in the Main Cropping System Experiment (MCSE) at the W. K. Kellogg Biological Station Long-Term Ecological Research (KBS-LTER) in Michigan, USA, from 1996 to 2011. We used models derived from population ecology to explore how weed diversity, temperature, and precipitation interact with crop yields. Using three types of models that considered internal and external (climate and weeds) factors, with additive or non-linear variants, we found that changes in weed diversity were associated with changes in rates of crop yield increase over time for both maize and soybeans. The intrinsic capacity for soybean yield increase in response to the environment was greater under more diverse weed communities. Soybean production risks were greatest in the least weed diverse systems, in which each weed species lost was associated with progressively greater crop yield losses. Managing for weed community diversity, while suppressing dominant, highly competitive weeds, may be a helpful strategy for supporting long term increases in soybean productivity. In maize, there was a negative and non-additive response of yields to the interaction between weed diversity and minimum air temperatures. When cold temperatures constrained potential maize productivity through limited resources, negative interactions with weed diversity became more pronounced. We suggest that: (1) maize was less competitive in cold years allowing higher weed diversity and the dominance of some weed species; or (2) that cold years resulted in increased weed richness and prevalence of competitive weeds, thus reducing crop yields. Therefore, we propose to control dominant weed species especially in the years of low yield and extreme minimum temperatures to improve maize yields. Results of our study indicate that through the proactive management of weed diversity, it may be possible to promote both high productivity of crops and environmental sustainability.RF gratefully acknowledges receipt of a grant from the Fundación Carolina. JG and RF were supported by FEDER (European Regional Development Funds) and the Spanish Ministry of Economy and Competitiveness funds (AGL2012-33736 and AGL2015-64130-R). RF and ML acknowledge financial support from Center of Applied Ecology & Sustainability (CAPES; CONICYT FB 0002-2014).Peer Reviewe

Histologic and Histomorphometric Analysis of Posterior Region of the Human Temporomandibular Disc

Objective The aim of this study was to analyze histologic and histomorphometric features of the articular disc in groups with and without disc displacement. Study design A sample of 39 temporomandibular joints TMJs (31 case specimens, 8 control specimens) from 28 patients (mean age 31.2 years) were recruited for this study. The patients were considered to be affected and treated surgically with disc repositioning when presenting painful clinical signs of disc displacement after unsuccessful nonsurgical treatment for at least 6 months. Of the control patients, 4 presented condyle fracture which required opening to be reduced for treatment, and 4 displayed active condyle hyperplasia. The posterior region of the disc was removed and sent for histologic and histomorphometric analysis. Histologic (hematoxylin-eosin) and histomorphometric (picro-Sirius red) analyses were performed. Statistically significant differences between the analyzed groups were accessed through the chi-squared test (P ≤ .05). The Mann-Whitney U test was used to observe the differences between mean values when variables did not present normal distribution [Kolmogorov-Smirnov(a) test]. Results There were no significant differences between the groups in relation to the parameters studied by histologic and histomorphometric analysis (using or not using polarization). Conclusions To the limits of this study, there were no significant histologic and histomorphometric differences in the articular disc between groups with and without TMJ dysfunction

A geometrical interpretation of critical exponents

We develop the hypothesis that the dynamics of a given system may lead to the activity being constricted to a subset of space, characterized by a fractal dimension smaller than the space dimension. We also address how the response function might be sensitive to this change in dimensionality. We discuss how this phenomenon is observable in growth processes and near critical points for systems in equilibrium. In particular, we determine the fractal dimension $d_f$ for the Ising model and validate it via computer simulations for two dimensions

Single nucleotide polymorphisms from Theobroma cacao expressed sequence tags associated with witches' broom disease in cacao

In order to increase the efficiency of cacao tree resistance to witches¿ broom disease, which is caused by Moniliophthora perniciosa (Tricholomataceae), we looked for molecular markers that could help in the selection of resistant cacao genotypes. Among the different markers useful for developing marker-assisted selection, single nucleotide polymorphisms (SNPs) constitute the most common type of sequence difference between alleles and can be easily detected by in silico analysis from expressed sequence tag libraries. We report the first detection and analysis of SNPs from cacao-M. perniciosa interaction expressed sequence tags, using bioinformatics. Selection based on analysis of these SNPs should be useful for developing cacao varieties resistant to this devastating disease. (Résumé d'auteur

Designing and implementing interdisciplinary projects in a systems engineering master programme

Interdisciplinary projects (IP) carried out by teams of students have been recognized as an important approach for learning in several fields and at several levels of education. In higher education, it can be an important drive for student learning motivation and an advantage for students when entering the working marketplace. The experience acquired while developing IP gives students technical and transversal competences highly relevant for employment but above all give students confidence and a competitive advantage. This paper aims at describing and discussing an experience in carrying out interdisciplinary projects in the context of a System Engineering Master (SEM) programme. First we explore the SEM programme philosophy and organization focussed on IP-based learning and then, for a particular IP course unit of the SEM, the dimensions of project design and specification, project interdisciplinarity, teaching team organization, support to students, project evaluation and individual students’ assessment. The authors argue that the IP learning model adopted in the case here reported is a good example of an IP-based learning at a master degree level.This study had the financial support of COMPETE: POCI-01-0145-FEDER-007043 and FCT -Fundação para a Ciência e Tecnologia within the Project Scope: UID/CEC/00319/201

A luminescent molecular thermometer for long-term absolute temperature measurements at the nanoscale

El pdf del artículo es la versión post-print.A unique Eu3+/Tb3+ luminescent self-referencing nanothermometer allowing absolute measurements in the 10–350 K temperature range and sub-micrometer spatial resolution is reported (see Figure). It has up to 4.9%·K−1 temperature sensitivity and high photostability for long-term use. The combination of molecular thermometry, superparamagnetism and luminescence in a nanometric host matrix provides multifunctionality opening the way for new exciting applications.We acknowledge Fundação para a Ciência e a Tecnologia (FCT, Portugal), COMPETE and FEDER programs (PTDC/CTM/101324/2008) and Integrated Spanish-Portuguese Action PT2009–0131 for fi nancial support. The work in Zaragoza has been supported by the grants MAT2007–61621 and CONSOLIDER CSD2007–00010 from the Ministry of Education. CDSB (SFRH/BD/38472/2007) and PPL (SFRH/BPD/34365/2006) thank FCT for grants.Peer Reviewe

Composite carbon materials from winery composted waste for the treatment of effluents contaminated with ketoprofen and 2-nitrophenol

The present work consisted of preparing and characterizing composite carbon materials (WRCC) from raw winery residues (WR) activated with zinc chloride to produce a carbon adsorbent. The WRCC was used for the adsorption of emerging contaminants in aqueous media. The WRCC presented a morphology with favorable characteristics for the adsorption process, giving an abundant porous structure with pores of different sizes. The results show the WRCC’s effectiveness, presenting surface area values (227 m2 g−1) and total pore volume (0.175 cm3 g−1). The general order kinetic model predicted the experimental curves sufficiently. The Sips model better described the two adsorbates' equilibrium data, with maximum adsorption capacities of 376.0 and 119.6 mg g−1 for 2-nitrophenol and ketoprofen, respectively. The WRCC carbon material was also highly efficient, with maximum removal of 81.4% and 94% in 1000 mg L−1 of the compounds 2-nitrophenol and ketoprofen. Finally, the prepared material has essential characteristics that make it an efficient adsorbent in treating effluents with emerging contaminants