Miracle-dz/UniFAR-FTUs huggingface dataset:
Jaime Pedro Oliveira da Silva

This thesis studies the dielectric constant and electrical conductivity of polymer composites with embedded high aspect ratio fillers. It is mainly focussed on the influence of the aspect ratio, filler concentration and orientation on the electrical response of the composite. These composites are of large importance in the development of materials for sensor and actuators. The thesis starts by exploring the dielectric constant of carbon nanotube/polymer composites. It was found that an increase of the aspect ratio of the fillers increases the dielectric constant of the nanocomposite for a given volume fraction. It was also demonstrated that nematic materials show a lower dielectric constant when compared to isotropic ones. It was concluded that for nematic state materials with different aspect ratios, the dielectric constant follows a power law. The conductivity of carbon nanotube/polymer nancomposites was also addressed by using a model based on ”hard-core” cylinders and it was demonstrated that simulations based on hard-core cylinders can describe the conductivity of the nanocomposites. It was demonstrated that increasing aspect ratio increases the electrical conductivity and that increasing the anisotropy will decrease conductivity; this effect being more evident at higher volume fractions. It was also shown that the microstructure generated by a derivation of sequential packing algorithm can be described by a random graph and that the electrical conduction in carbon nanofiber/polymer composites can be described by a Bethe lattice. Through the use of the complex network framework, an expression is obtained for the percolation threshold. In the same way, it was demonstrated that ”hopping” between adjacent fillers results on an expression that corresponds to a weak disorder regime. The critical exponents for a hard-core 3D cylinder system with shortrange interaction were calculated, making use of the network theory. It was demonstrated that these are related through the common hyperscaling for a 3D system and do not belong to the same universality class as the lattice percolation. The application of the developed model to carbon nanofiber/Epoxy composites prepared with different carbon nanofiber dispersion methods, reveals that the dispersion methods induce a strong influence on the composite electrical properties that can be captured by the model. It is also found that the electrical conductivity can be described by a weak disorder regime, a regime where all fiber-fiber conductive links participate in the overall composite conductance. The model was also applied to carbon nanotube/poly(vinylidene fluoride) composites prepared using fillers with different oxidation and ther-
PHYSICOCHEMICAL CHARACTERISTICS AND FINITE ELEMENT SIMULATION OF FIRMNESS IN SOURSOP FRUITS (Annona muricata L. cv. Elita) DURING POSTHARVEST

Soursop fruits (Annona muricata L. cv. Elita) at different ripening stages were evaluated for their physico-chemical characteristics: total soluble solids (TSSs), acidity, and pH. Firmness was determined through the application of puncture textural tests. The modeling and simulation of this parameter was carried out on Autodesk Inventor Professional 11.0 (ANSYS® Technology). The fruits showed an upward trend regarding TSS and acidity, reaching maximum values of 12.8 °Brix, 0.74% acidity, and a pH below 3.43; all of which coincide with consumption maturity as observed on day 6. Firmness showed a decreasing trend throughout the entire postharvest period, with values of 79.43 N for day 0, and 3.62 N for day 9. Finite element modeling, the simulation of firmness, and its correlation with experimental data allowed for us to calculate the fracture force of the fruits with an exactness of more than 90%. Since it prevents the physical alteration of the product, this application becomes a nondestructive alternative for firmness assessment, useful in storage, transport, fresh consumption, packaging, and processing.
Influence of genotype on the quality of sheep leather

The objective of this study was to evaluate the influence of crossings between sheep breeds on the intrinsic quality of leather. It was used the skins of 36 lambs (18 females and 18 males), resulting from crosses between ewes of a native breed from the Brazilian state of Mato Grosso do Sul and rams of the same native breed as well as the Texel and Santa Ines genetic groups. The animals were raised in confinement until slaughter weight, from 28 to 32 kg. After slaughter, samples were taken from the skins for histological analysis. The skins were tanned with chromium, retanned and greased. It was taken from the leather samples for electromicrographs and for tests for tensile and tear strength (intrinsic quality). Morphological aspects from the skin as well as from the leather help to understand the results found and they evidence that breeds or crossings among breeds interfere in the intrinsic quality of leather and skin of sheep.
The early stages of fatigue and evolution of persistent slip bands in a copper single crystal

Abstract Low-amplitude constant plastic cyclic deformation of copper single crystals oriented for single slip [123] was carried out at room temperature in air. The plastic shear strain amplitude was 1 × 10−3. The observation of dislocation structure evolution in the early stages of fatigue and the investigation of the formation of persistent slip bands (PSBs) in the latter stage were conducted using the scanning electron microscopy electron channelling contrast technique. Inspecting the variations in shape and distribution of matrix walls for different numbers of cycles, dislocation evolution in the early cyclic deformation was roughly divided into two stages. During the evolution process, the primary edge dislocations on the primary slip planes and the screw segments between matrix walls may play a key role in the two successive stages respectively. From the observation of PSB initiation and of its morphology and dislocation structure, a possible mechanism for PSB formation was proposed. It was suggested that, once the spacing between matrix walls and the width of the matrix walls reached critical values, the collapse of a matrix wall which was caused by the unbalance of the forces exerted by crew segments could induce collapse of an adjacent matrix wall. Therefore a persistent slip line (PSL) was formed consequently. Along the PSL, the neighbour screw segments would strongly activate and finally induce the formation of the ladder structure of a PSB.
A test of the maximum power hypothesis along an elevational gradient in the Luquillo Mountains of Puerto Rico

The maximum power principle predicts that maximum transformation of available energy into useful work occurs when a system operates at an intermediate rate and efficiency. This relation is apparent in everyday situations as we shift gears to keep near the middle of each gear range when we accelerate an automobile, or operate chain saws and other machines at a load about half their stalling rate. We tested the validity of the maximum power principle in a complex natural system by quantifying patterns of photosynthesis and respiration – an ecosystem’s energy currency – along an elevation gradient in a subtropical forest of Puerto Rico. This mountain system was a useful proxy for testing the hypothesis over broader climatic gradients elsewhere. Our results indicate that metabolic rates (defined as gross primary productivity) decrease up the gradient, efficiency (defined as the ratio of net to gross primary productivity) increases up this gradient, and power (defined as net primary productivity, or the amount of useful energy produced within a given ecosystem per unit time) is maximum near the midpoint of the gradient where rate and efficiency are intermediate. These observations are non-trivially consistent with the maximum power principle and support a scalable, energy-based definition of evolutionary fitness. Given a set of environmental forcing functions in a given location, those individuals (or populations or ecosystems) that optimize the trade-off between metabolic rate and efficiency to achieve maximum power will be most fit. As environmental conditions change over the long term, this rate vs efficiency optimum will shift and those that are able to achieve maximum power in the new environment will be favored over those that are maximizing power for the old environment. We think that this net energy-as-fitness view allows for a richer series of possibilities for testing the consequences of natural selection.
The Role of Oxidative Stress in the Etiopathogenesis of Gluten-sensitive Enteropathy Disease

Summary Background: The objective here is to examine the role of overall oxidative stress in the etiopathogenesis of gluten-sensitive enteropathy disease and its relationship with gluten free diet and autoantibodies. Methods: Eighty gluten-sensitive enteropathy patients and 80 control group participants were included in the study. As oxidative stress parameters, we researched total antioxidant status (TAS), total oxidant status (TOS), oxidative stress index (OSI), paraoxonase-1 and arylesterase parameters in the serum samples of gluten-sensitive enteropathy patients. Results: In comparison to the control group, gluten-sensitive enteropathy patients had lower TAS, paraoxonase-1 and arylesterase levels and gluten-sensitive enteropathy patients had considerable TOS and OSI levels. In contrast, patients who agreed to the gluten free eating routine had a higher OSI proportion and patients who did not conform to the gluten free eating regimen had a lower paraoxonase-1 level. An affirming reciprocation was de tected amidst TOS and OSI proportion and gluten-sensitive enteropathy autoantibodies and C-reactive protein levels and a negative correlation was found between arylesterase level and gluten-sensitive enteropathy autoantibodies. Conclusions: We observed oxidative stress levels to be higher in gluten-sensitive enteropathy patients contrasted with the control group. Oxidative stress level showed differences in gluten-sensitive enteropathy patients depending on gluten diet content and autoantibody positivity. In point of fact, C-reactive protein and gluten-sensitive enteropathy autoantibodies are identified with oxidative anxiety parameters resulting in the possibility that oxidative stress might be successful in the gluten-sensitive enteropathy pathogenesis.
Low-Frequency North Atlantic Climate Variability in the Community Earth System Model Large Ensemble

AbstractThere is observational and modeling evidence that low-frequency variability in the North Atlantic has significant implications for the global climate, particularly for the climate of the Northern Hemisphere. This study explores the representation of low-frequency variability in the Atlantic region in historical large ensemble and preindustrial control simulations performed with the Community Earth System Model (CESM). Compared to available observational estimates, it is found that the simulated variability in Atlantic meridional overturning circulation (AMOC), North Atlantic sea surface temperature (NASST), and Sahel rainfall is underestimated on multidecadal time scales but comparable on interannual to decadal time scales. The weak multidecadal North Atlantic variability appears to be closely related to weaker-than-observed multidecadal variations in the simulated North Atlantic Oscillation (NAO), as the AMOC and consequent NASST variability is impacted, to a great degree, by the NAO. Possible re.
Causes, Consequences and Policy implications of Squatter Settlement in Gondar Town in the Case of Kebele 18

Abstract Objective : the principal objective of the study is to assess the causes and consequences of squatter settlements in the light of unplanned expansion of the built-up area and policy responses to it. Methods : in order to achieve the study objective, in-depth interview with 20 household heads and municipal administrators’ documentary analysis and observational techniques were used. Results: major findings of the study indicate that emergence of squatter settlements in the study area is a recent phenomenon that has occurred since 2005. High building standards of the legal houses, delayed responses, and procedural problems of the legal land provision, and high housing rents in the city centre were identified by respondents as the causes of squatting in the study area. In addition, less government control of open spaces, the limited capacity of the code enforcement service to control illegal house construction, lack of a comprehensive legal response towards the problem of squatting, and the practice of land sale by land speculators as a means of making profit are other factors that have contributed to the emergence and proliferation of squatter settlements. Compared to the plot sizes of the legal land provision, the plot sizes of the squatter settlements in the study area are large and there are undeveloped vacant fenced plots between squatter housing units. Thus, land in the area is inefficiently exploited and the situation has greatly contributed to the unplanned and rapid horizontal expansion of the built-up area of the town. Keywords : Squatter settlement, policy implications and illegal house
Predicting spatial and temporal effects of climate change on the South American lizard genus Teius (Squamata: Teiidae)

The consequences of past or future climate change have been studied in many physical and biological systems, and their effects could change the ecology and spatial distribution of suitable areas for a wide variety of organisms. We analyzed the environmental and geographic space of the current suitable area projecting these conditions into Mid-Holocene and 2050 RCP8.5 scenarios to quantify whether climate change would affect the distribution and size of environmental and geographic space for lizard species of the genus Teius. The potentially suitable geographic area for the Mid-Holocene was found to be smaller than today for T. oculatus (−29.55%) and for T. teyou (−6.82%), but for T. suquiensis it was inferred as a larger suitable area (+26%). For the future scenario all species showed a decrease in the potentially suitable area compared to the present (T. oculatus = − 9.30%, T. teyou = − 0.79%, T. suquiensis = − 37.58%). The PCA axes that in the environmental space showed a higher contribution for PC1-2 in Mid-Holocene and Present were mostly related to temperature and for PC3 with altitude variables, for the 2050 scenario were temperature for PC1, precipitation for PC2 and altitude-temperature for PC3. The current Teius’ potentially suitable geographic space results versus the other temporal forecasts, showed specific differences in magnitude changes. This work illustrates how ectothermic organisms might have to face major changes in their environmental and geographic space as a consequence of the effect of climate changes.
Reserves of Natural Resources in a Small Open Economy

This paper studies the effect of a shock to resource prices in a small open economy where the stock of natural resources is responsive to exploration activity, and where extraction reduces the future availability of reserves. We show that the effects of a resource price shock on resource investment, labour utilisation and extraction are all amplified in the presence of endogenous reserves. We also find that spillovers to broader economic activity, including changes in domestic production, non-resource exports and consumption, are all greater in the presence of exploration activity. However, we find that incorporating endogenous reserves does not fundamentally change the effects of a resource price shock on key price measures including consumer prices, the real exchange rate and domestic interest rates.
Comparison of Fixed Point Realisations between Inmetro and PTB

An interlaboratory comparison in the temperature range between −190 °C and 420 °C was organised between the National Institute of Quality, Normalisation and Industrial Quality (Inmetro), Brazil, and the Physikalisch Technische Bundesanstalt (PTB), Germany. This comparison followed the same protocol as the EUROMET project 552 comparison and was carried out in the years 2001–2002. A standard platinum resistance thermometer (SPRT) of 25 Ω was calibrated at the temperature fixed points of Ar, Hg, the triple point of water (TWP), Ga, In, Sn and Zn, with at least three realisations of each fixed point at both institutes. The uncertainty evaluation is given by Inmetro and some differences in the calibration procedures or in the measuring instruments used are described. The agreement between the results of laboratories was not in all cases within the combined uncertainties. Results of other comparisons are presented, which give additional information on the equivalence of the realised temperature scales.
The Effect of University Teachers’ Workplace Spirituality on Employee Engagement: Professional Commitment as Mediator

The current research on workplace spirituality effect is mainly carried out in the west, lacking evidence of China background and attention to university teachers, although the groups are called soul engineer in China. In order to test the effect of workplace spirituality on employee engagement of Chinese university teachers, this study collected239 samples by convenient sampling. The results of structural equation model test showed that the workplace spirituality of university teachers had a positive impact on their engagement, in which professional commitment played a partly mediating role. The results suggest that universities should strengthen their spirituality construction through various strategies.
Life-Cycle Expenditure and Retirees’ Cost of Living

The aim of this paper is threefold. First, we document the expenditure life-cycle profile in the United Kingdom and show how differences in the consumption bundle of pensioners and workers translates into different inflation experiences. Albeit differences in given years, the inflation experienced by the two groups is not significantly different over a long time period. Secondly, we estimate a demand system and compute the change in the cost of living and the substitution effect for both pensioners and workers for the period 1990-2009. Finally, we show how pension income would evolve during that period under three alternative indexation measures. Adjusting pension income by the RPI results in a higher income than adjusting by the cost of living index or household inflation
Morphological Characterization and Proximate Analysis of Three Edible Mushrooms in Plateau and Kogi States, Nigeria

The study examined the morphological and proximate compositions of three edible mushrooms including Termitomyces clypeatus R. Heim, Lentinus squarrosulus Mont. and Lentinus tigrinus (Bull.) Fr. in Plateau and Kogi States, Nigeria. The collection of the fruiting bodies was done at random during the rainy season (July to September). The fruiting bodies of the macrofungi at the point of collection were photographed on site and the important morphological features were recorded before collection and packaging. The moisture content, protein content, total carbohydrate, ash content, crude fiber and crude fat compositions of the edible mushrooms were determined. T. clypeatus mushroom had a significantly (p≤0.05) higher moisture content (91.67%) and lower crude protein content (2.5%), compared to L. tigrinus and L. squarrosulus. T. clypeatus mushroom had a significantly (p≤0.05) lower crude fiber (2.10%) and crude fat (2.27%) contents, compared to the significantly higher (p≤0.05) crude fiber and crude fat compositions of L. tigrinus and L. squarrosulus. The ash content and carbohydrate content of the mushrooms species ranged from 0.90% to 20.33% and 6.88% to 26.18% respectively. Based on the high nutritional value of the three edible mushrooms assessed, it can thus be inferred that the mushrooms are valuable diet assets.
miR-499 rs3746444 polymorphism is associated with colorectal cancer susceptibility: A case-control study in a Chinese population

Background: Previous study suggested that miR-499 rs3746444 may contribute to the risk and prognosis of Colorectal Cancer (CRC). However, other studies did not support association between rs3746444 and CRC risk. Therefore, we did this study to assess whether miR-499 rs3746444 affect the risk of CRC. Method: A total of 913 subjects were included in this case-control study, including 434 patients with CRC and 479 healthy controls. The miR-499 rs3746444 was genotyped using the TaqMan methodology in 96-well plates and read with the Sequence Detection Software (SDS, version 1.4) on an Applied Biosystems (ABI) 7500 Real-Time PCR System. Results: The miR-499 rs3746444 polymorphism showed significant difference between CRC patients and healthy controls in genotype comparison (TC vs. TT: OR = 1.37, 95% CI 1.01-1.88, P = 0.04; CC vs. TT: OR = 3.18, 95% CI 1.83-5.55, P<0.01; CC+TC vs. TT: OR = 1.64, 95% CI 1.22-2.24, P<0.01). Additionally, the miR-499 rs3746444 T allele was significantly associated with CRC risk (OR=2.89, 95% CI 1.69-5.09, P<0.01). Conclusion: The results of our study suggested that miR-499 rs3746444 was significantly associated with CRC risk.
Campaign Comics: The Use of Comic Books for Strategic Political Communication

Political parties have long used comic books in their political campaigns. Whereas both ideological and political messages in comics as well as the social and political commentary in editorial cartoons have received vast scholarly attention, comic books and their use for strategic communication are rarely addressed. Thus, this article discusses the use of comic books in political campaigns and analyzes the mass media discourse on comic books used in the 2010 election campaign in Vienna, Austria. Results show the actors in the coverage put special focus on the violent and xenophobic content of the comics. Although these types of content gained much attention, the media failed to discuss the suitability of comics for political purposes.
K-means clustering and STRUCTURE analyses of genetic diversity in Tamarix L. accessions

Tamarix L. accessions were collected from Sistan and Baluchestan Province of Iran, covering an area of about 60 km located in the southeast of Iran. The present investigation was performed to study the genetic structure of Tamarix populations in this province and present some information about gene flow among these populations. Forty-two tree specimens were randomly collected and studied for molecular and morphological diversity. Based on morphological descriptions we recognized 3 species that were confirmed by detailed morphometric and genetic analysis. The studied tree specimens were separated in 3 distinct clusters by UPGMA clustering and principal coordinate analysis and multidimensional scaling ordination methods. Clustering of molecular (ISSR) data showed some degree of genetic variation within each species. Similarly, STRUCTURE analysis and K-means clustering revealed some degree of genetic admixture among the studied accessions. NeighborNet and reticulograms revealed some degree of gene exchange among the studied populations. AMOVA and the Hickory test showed significant genetic differences of the studied populations and the Mantel test showed significant correlation between genetic distance and geographical distance of these populations.