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Steep slope vineyards are a complex scenario for the development of ground robots. Planning a safe robot trajectory is one of the biggest challenges in this scenario, characterized by irregular surfaces and strong slopes (more than 35°). Moving the robot through a pile of stones, spots with high slope or/and with wrong robot yaw may result in an abrupt fall of the robot, damaging the equipment and centenary vines, and sometimes imposing injuries to humans. This paper presents a novel approach for path planning aware of center of mass of the robot for application in sloppy terrains. Agricultural robotic path planning (AgRobPP) is a framework that considers the A* algorithm by expanding inner functions to deal with three main inputs: multi-layer occupation grid map, altitude map and robot’s center of mass. This multi-layer grid map is updated by obstacles taking into account the terrain slope and maximum robot posture. AgRobPP is also extended with algorithms for local trajectory replanning during the execution of a trajectory that is blocked by the presence of an obstacle, always assuring the safety of the re-planned path. AgRobPP has a novel PointCloud translator algorithm called PointCloud to grid map and digital elevation model (PC2GD), which extracts the occupation grid map and digital elevation model from a PointCloud. This can be used in AgRobPP core algorithms and farm management intelligent systems as well. AgRobPP algorithms demonstrate a great performance with the real data acquired from AgRob V16, a robotic platform developed for autonomous navigation in steep slope vineyards.
Stomach contents analysis and stable isotope results indicate M. hubbsi is a generalist predator that feeds mainly on demersal fishes, followed by crustaceans and cephalopods. Ontogenetic changes in diet were identified, with fish importance increasing in the diet with hake size. Smaller hake (<250 mm) fed mostly on the sepiolid Semirossia tenera (89.45%IRI) and engraulid fish (89.96%IRI). Mid-sized hake (250–300 mm) fed mainly on benthic fish such as Bellator brachychir (95.63%IRI) and euphausiids (56.46%IRI), while larger hake (>300 mm) fed heavily on Dactylopterus volitans (94.80%IRI) and occasionally on a variety of teleosts. Significant correlations between δ13C (P < 0.05), THg (P < 0.001) and hake size occurred, whereas no relationship was observed between δ15N and hake size or δ15N and total mercury. Signatures were lowest in smaller hake with a tendency of increasing with size. Smaller and larger hake were significantly different in δ13C. Differences regarding isotopic niche width were quantified for each size group; trophic diversity and trophic redundancy among them were negligible, but hake >300 mm possibly have a larger feeding plasticity due to the combination of prey from a wide trophic level range.
In energy storage systems, every component that makes up an electrode can greatly affect the electrochemical performance. One example includes the so-called “binders” used in secondary batteries. Herein, we compare the influence of using polyvinylidene fluoride (PVDF) or sodium carboxymethyl cellulose (CMC) on the electrochemical performance of an aluminium chloride battery (ACB) system. The active material of the cathode was a reduced graphene oxide dried under supercritical conditions (RGOCPD). Interestingly, while PVDF enabled one of the highest capacities reported for ACBs, the CMC resulted in a significant degradation of the cell’s performance.
This study aimed to calculate economic values (EVs) and economic selection indices for milk production systems in small rural properties. The traits 305-d milk yield in kg (MY), fat (FP) and protein (PP) percentage, daily fat (FY) and protein (PY) yield, cow live weight in kg (LW), calving interval (CI), and logarithm of daily somatic cell count (SCC) in milk were considered the goals and selection criteria. The production systems were identified from 29 commercial properties based on the inventory of revenues and costs and of zootechnical field data. Later, bioeconomic models were developed to calculate the productive performance, revenues, and costs concerning milk production to estimate EVs, which were calculated as the difference in annual profit with dairy production resulting from a change in one unit of the trait while keeping the others constant and dividing the value by the number of cows. After the EVs were known, ten economic selection indices were estimated for each system so they could be compared by modifying the selection criteria and calculating the relative importance of each selection criteria, the accuracy of the economic selection index, and response expected to the selection in USD, among other parameters. One of the systems detected was called less intensive (LS) and was characterized by having ten cows in lactation that produced 13·5 l/d and consumed 1·8 kg of concentrate/d. The second system detected was called more intensive (IS) and had 22 cows in lactation that produced 17·5 l/d and consumed 3·4 kg of concentrate/d. Monthly profits per cows in lactation of USD 2·60 and USD 68·77 were recorded for LS and IS, respectively. The EVs of the traits MY, FP, and PP were all positive, while for the other traits they were all negative in all situations. The best economic selection indices were those featuring selection criteria MY, LW, and CI, while the trait LW had the greatest importance in both systems. These results indicate that animal frame must be controlled in order to maximize the system's profit.
Five scarabs and one scaraboid found in Vinha das Caliças 4 (Beja, Portugal) were analyzed using a micro-analytical methodology in order to determine their mineralogical and chemical composition. Microstructural characterization and chemical analysis revealed that all were composed of a white body of crushed feldspathic sand covered by a lead-rich, alkaline-depleted silicate blue-green glaze showing evident signs of glass deterioration. Variable pressure scanning electron microscopy with X-ray energy dispersive spectrometry, handheld X-ray fluorescence spectroscopy, and micro X-ray diffraction results show that blue-green color of the glaze was produced by using copper ions (Cu2+) in conjunction with the lead antimonate bindheimite, a yellow-colored opacifier. The introduction of small amounts of tin in the structure of bindheimite enabled the production of a ternary Pb–Sb–Sn oxide. Tin, which was most likely added with the copper source (bronze scrapings), is known to facilitate the crystallization of bindheimite. The results are consistent with the five scarabs and one scaraboid being manufactured in Egypt. This study, the first archeometric study of scarabs found in the Iberian peninsula, has greatly contributed to the understanding of the influence of the Eastern and Central Mediterranean world in the Southwestern Iberia during the first millennium B.C.
We report experimental observations of turbulent flow with spherical particles in a square duct. Three particle sizes, namely
, 16 and 9 (
being the duct full height and
being the particle diameter), are investigated. The particles are nearly neutrally buoyant with a density ratio of 1.0035 and 1.01 with respect to the suspending fluid. Refractive index matched–particle image velocimetry (RIM–PIV) is used for fluid velocity measurement even at the highest particle volume fraction (20 %) and particle tracking velocimetry (PTV) for the particle velocity statistics for the flows seeded with particles of the two largest sizes, whereas only pressure measurements are reported for the smallest particles. Settling effects are seen at the lowest bulk Reynolds number
10 000, whereas, at the highest
, particles are in almost full suspension. The friction factor of the suspensions is found to be significantly larger than that of single-phase duct flow at the lower
investigated; however, the difference decreases when increasing the flow rate and the total drag approaches the values of the single-phase flow at the higher Reynolds number considered,
. The pressure drop is found to decrease with the particle diameter for volume fractions lower than
for nearly all
investigated. However, at the highest volume fraction
, we report a peculiar non-monotonic behaviour: the pressure drop first decreases and then increases with increasing particle size. The decrease of the turbulent drag with particle size at the lowest volume fractions is related to an attenuation of the turbulence. The drag increase for the two largest particle sizes at
, however, occurs despite this large reduction of the turbulent stresses, and it is therefore due to significant particle-induced stresses. At the lowest Reynolds number, the particles reside mostly in the bottom half of the duct, where the mean velocity significantly decreases; the flow is similar to that in a moving porous bed near the bottom wall and to turbulent duct flow with low particle concentration near the top wall.
Soluble phosphate availability is a major limiting factor for plant growth, development, and yield. To assure a constant phosphorous supply, plants employ both high- and low-affinity phosphate acquisition mechanisms. Glyphosate is an herbicide widely used throughout the world, and previous studies have suggested that it can be transported across the plasma membrane via phosphate transporters in herbaceous species. The effects of phosphate status on glyphosate uptake were investigated in the tree grand eucalyptus (Eucalyptus grandis W. Hill ex. Maid.). Eucalyptus grandis’s putative phosphate transporters showed differential gene expression in leaves and roots in response to phosphate limitation. Overall, the expression of high-affinity phosphate transporters increased in phosphate-limiting treatments, particularly in roots. More [14C]glyphosate was absorbed and translocated in phosphate-limiting plants compared with control plants grown in phosphate-replete treatments. In leaf mesophyll protoplast assays, rapid uptake of [14C]glyphosate into protoplasts was observed, and addition of phosphate to the assays competed with [14C]glyphosate uptake. These data indicate that phosphate transporters represent one mechanism of glyphosate uptake in E. grandis. These results have implications for best management practices for weed control and glyphosate application under phosphate application regimes.
To assess the daily intake of polychlorinated biphenyls not similar to dioxins (NDL-PCB) derived from fish consumption in Spain and compare it with tolerance limits in order to establish a safe threshold so that the nutritional benefits derived from fish consumption may be optimized.
Analysis of NDL-PCB in fish samples and ecological study of the estimated intake of NDL-PCB from fish consumption in different Spanish population groups.
National representative sample of the Spanish population.
The intake of NDL-PCB was estimated in two different scenarios: upper bound (UB) and lower bound (LB). Estimating intake using the average concentration of NDL-PCB found in the fish samples, the intake for ‘other children’ is estimated as: 1·80 (UB) and 5·33 (LB) ng/kg per d at the 50th percentile (P50); 7·39 (UB) and 21·94 (LB) ng/kg per d at the 95th percentile (P95) of fish consumption. Estimated NDL-PCB intake shoots up in the toddler group, reaching values of 30·43 (UB) and 90·37 (LB) ng/kg per d at P95. Estimated intake values are lower than those previously estimated in Europe, something expected since in previous studies intake was estimated through total diet. In adults, our estimated values are 1·59 (UB) and 4·72 (LB) ng/kg per d at P50; 4·95 (UB) and 14·72 (LB) ng/kg per d at P95.
NDL-PCB concentration in fish is under the tolerance limits in most samples. However, daily intake in consumers of large quantities of fish should be monitored and special attention should be given to the youngest age groups due to their special vulnerability and higher exposure.
We use interface-resolved numerical simulations to study finite-size effects in turbulent channel flow of neutrally buoyant spheres. Two cases with particle sizes differing by a factor of two, at the same solid volume fraction of 20 % and bulk Reynolds number are considered. These are complemented with two reference single-phase flows: the unladen case, and the flow of a Newtonian fluid with the effective suspension viscosity of the same mixture in the laminar regime. As recently highlighted in Costa et al. (Phys. Rev. Lett., vol. 117, 2016, 134501), a particle–wall layer is responsible for deviations of the mesoscale-averaged statistics from what is observed in the continuum limit where the suspension is modelled as a Newtonian fluid with (higher) effective viscosity. Here we investigate in detail the fluid and particle dynamics inside this layer and in the bulk. In the particle–wall layer, the near-wall inhomogeneity has an influence on the suspension microstructure over a distance proportional to the particle size. In this layer, particles have a significant (apparent) slip velocity that is reflected in the distribution of wall shear stresses. This is characterized by extreme events (both much higher and much lower than the mean). Based on these observations we provide a scaling for the particle-to-fluid apparent slip velocity as a function of the flow parameters. We also extend the scaling laws in Costa et al. (Phys. Rev. Lett., vol. 117, 2016, 134501) to second-order Eulerian statistics in the homogeneous suspension region away from the wall. The results show that finite-size effects in the bulk of the channel become important for larger particles, while negligible for lower-order statistics and smaller particles. Finally, we study the particle dynamics along the wall-normal direction. Our results suggest that single-point dispersion is dominated by particle–turbulence (and not particle–particle) interactions, while differences in two-point dispersion and collisional dynamics are consistent with a picture of shear-driven interactions.
Using the Safe Islands for Seabirds LIFE project as a case study, we assessed the socio-economic impact of a nature conservation project on the local community, focusing on the wealth created and the jobs supported directly and indirectly by the project. The Safe Islands for Seabirds project took place during 2009–2012, mainly on Corvo Island, the smallest and least populated island of Portugal's Azores Archipelago. To assess the impact of the project we used a combination of methods to analyse the project expenditure, the jobs created directly as a result of it, and, by means of multipliers, the incomes and jobs it supported indirectly. We estimate that during 2009–2012 direct expenditure of EUR 344,212.50 from the project increased the gross domestic product of the Azorean region by EUR 206,527.50. Apart from the 4.5 jobs created directly by the project, it also supported indirectly the equivalent of 1.5–2.5 full-time jobs. The project also provided the opportunity to preserve and promote natural amenities important for the quality of life of the local community. Our findings show that a nature conservation project can have positive economic impacts, and we recommend the creation of a standardized tool to calculate in a straightforward but accurate manner the socio-economic impacts of conservation projects. We also highlight the need to design projects that support local economies.
We study turbulent channel flow of a binary mixture of finite-sized neutrally buoyant rigid particles by means of interface-resolved direct numerical simulations. We fix the bulk Reynolds number and total solid volume fraction,
, and vary the relative fraction of small and large particles. The binary mixture consists of particles of two different sizes,
is the half-channel height and
the diameters of the large and small particles. While the particulate flow statistics exhibit a significant alteration of the mean velocity profile and turbulent fluctuations with respect to the unladen flow, the differences between the mono-disperse and bi-disperse cases are small. However, we observe a clear segregation of small particles at the wall in binary mixtures, which affects the dynamics of the near-wall region and thus the overall drag. This results in a higher drag in suspensions with a larger number of large particles. As regards bi-disperse effects on the particle dynamics, a non-monotonic variation of the particle dispersion in the spanwise (homogeneous) direction is observed when increasing the percentage of small/large particles. Finally, we note that particles of the same size tend to cluster more at contact whereas the dynamics of the large particles gives the highest collision kernels due to a higher approaching speed.
Background: Dystrophinopathies are X-linked muscular dystrophies characterized by pathogenic mutations in the dystrophin gene. Symptomatic dystrophinopathy female carriers may present with limb-girdle weakness. The diagnosis may be challenging in the absence of affected male relatives. We aimed to describe the phenotypic variability in a series of molecular-confirmed female dystrophinopathy patients. Methods: This is a retrospective analysis of medical records from 1997 to 2015. Results: Ten female dystrophinopathy patients were selected, two with unusual phenotypes: one with early joint contractures muscular dystrophy and the other with very late onset myopathy. Muscle imaging studies demonstrated predominant asymmetric fat replacement. Muscle biopsy immunohistochemistry demonstrated clear mosaic pattern in two cases and only subtle reduction of dystrophin intensity in three. Conclusions: Adequate diagnosis is fundamental for genetic counseling and cardiologic follow-up. Female patients with dystrophinopathy may present unusual phenotypes such as early contractures and very late onset myopathy.
Fernand Braudel characterized 1480–1620 as the “long sixteenth century” of economic and population growth in Europe (Braudel 1982–1984, vol. 2). In Portugal too, after roughly 1480/1490, the upturn in the population numbers is one of the positive signs of this long-term cycle of prosperity. Growing trends started out from a situation in which low population densities were consistent with a high land–labor ratio typical of a “frontier economy.” From what is known about the rest of the Iberian Peninsula, this phase of demographic growth went together with a rise in per capita output, recovering to, though not exceeding, the levels that had existed before the Black Death (Álvarez Nogal and Prados de la Escosura 2013). The Portuguese economy may have followed a different path. Recent estimates suggest that output per capita decreased (Palma and Reis 2016). However, while per capita agricultural production declined, the Portuguese intercontinental trade reached its peak years by comprising offshoots in America, Africa, and Asia. Dealings overseas are one of the most studied features of Portugal's economy. The effects of these trade flows on per capita gross domestic product (GDP) in European colonial powers remain an open and controversial issue (O'Brien and Prados de la Escosura 1998). Some scholarly insights point to colonial trade as the cause of living standard improvements in the mother country. Although there is no agreement about the significance of that contribution, it is certain that it grew throughout the early modern period and achieved its higher impact in the late eighteenth century. Therefore, during the first hundred-year period of the history of the empire, in which the route of the Cape of Good Hope earned a particular advantage over other imperial resources, the colonial trade had a negligible effect on the GDP, though it fostered sectors like shipbuilding and shipping.
This chapter examines the evolution of domestic production and estimates the contribution of resources provided by the empire. During the period under analysis, roughly from 1480 to 1620, Portugal became a kingdom integrated in the Habsburg monarchy (1580). The history of the empire points to the relative advantages Portugal reaped from the political union, since it created new opportunities for slave traffic paid with silver, controlled by Portuguese merchants. Silver was at the time the most important item in the Portuguese Cape Route.
This book offers a fascinating exploration of the evolution of the Portuguese economy over the course of eight centuries, from the foundation of the kingdom in 1143, when political boundaries began to take shape in the midst of the Christian Reconquista of the Iberian Peninsula, and the formation of an empire, to the integration of the nation into the European Communities and the Economic and Monetary Union. Through six chapters, the authors provide a vibrant history of Portugal's past with a focus ranging from the medieval economy and the age of globalization, to war and recovery, the Atlantic economy, the rise of liberalism and patterns of convergence. The book provides a unique long-term perspective of change in a southern European country and its empire, which responds to the fundamental broader questions about when, how and why economies expand, stagnate or contract.
The main feature of the Portuguese economy in the twentieth century was both a rapid transformation and a slow but consistent catching-up to the living standards of the European forerunners. The convergence of the Portuguese income per capita and productivity levels commenced soon after the end of World War I and continued throughout the Republican regime, which lasted until 1926, in spite of the high levels of political instability. During those early years, economic growth was to a large extent linked to tariff protectionism and to direct state intervention in the economy. That process was not unique to Portugal, as it occurred in most of the poorer European periphery, where rates of economic growth increased to unprecedented levels. World War II led to an inevitable halt in economic growth, but Portugal's neutrality spared the country deeper consequences and created opportunities for the expansion of a few economic sectors, namely those linked to exports. The post–World War II years were the best ever for the Portuguese economy, which saw levels of income and productivity converge faster with those recorded in Europe's most advanced countries, namely in the major industrial powers. This convergence trend was shared by most peripheral countries in Europe, regardless of their political regime, and lasted until 1973. During the golden years or growth, Portugal and the rest of Europe had economic policies which tended to foster a greater opening to the outside, and a greater presence of the state in the economies. In terms of the structure of the economy, faster growth led to a swift industrialization of the country, an increase in the weight of the services sector, a decline in the importance of agriculture, and an increase in the weight of foreign trade, and higher participation of foreign capital in national investment.
Political discontent and the colonial wars led to yet another revolution, in 1974, which immediately followed the year of the international crisis caused by the end of the Bretton Woods system and the soar in oil prices in the world markets. A period of political instability ensued, lasting until 1976 or 1977, and in this year Portugal applied to join the European Communities, which it eventually did in 1986.
By the end of 1807, a French army led by General Junot entered Portugal at the northern border with Spain, to take Lisbon, the capital of the empire and main center of the commercial activity of the country, the city that was being used by the British despite the Continental Blockade Napoleon had decreed a year earlier. Prince Regent João, who had agreed on the French embargo to avoid war, fled from the French troops and embarked to Brazil, ending up in Rio de Janeiro by the beginning of 1808. The French invaded Portugal on two other occasions, in 1808 and 1811, and were finally expelled with the help of the British on the later date. Yet these events were to put an end to the old regime and leave the door open to the implementation of a parliamentary regime, much like those that would be introduced elsewhere in Europe. In 1820, a liberal revolution took place followed by the election of a Constitutional Assembly and adoption of a new constitution in 1822. This was only the beginning. The transition from the Ancién Régime to the new liberal order, however, took the best part of the first half of the nineteenth century and was punctuated by military coups, civil wars, and uninterrupted political unrest. The extent of the long institutional transformation was closely related to Portugal's level of economic, political, and social backwardness, which clearly made more difficult the needed consensus for change. To a certain extent, the implementation of the new political framework and the liberal economy emerging from it had to wait for another military coup, in 1851, the Regeneração, which ultimately led to the pacification of Portuguese society, at least for some decades, until other sources of distress emerged with the advent of the Republican forces.
The British Industrial Revolution and the spread of industrialization that ensued throughout the nineteenth century widened the gap in levels of income per capita within Europe, clearly distinguishing a core of industrializing countries and an outer periphery, to the south and the east, where the prevalence of backward agriculture lasted for several decades up to the twentieth century. It still is a point of lively discussion in the literature to define when that “little divergence” commenced in the European continent, whether it is a heritage from the Ancién Régime or a feature of the century of industrialization.
Portugal became an independent kingdom in the twelfth century, and just over one hundred years later had established the borders it still has today. Portugal's nationhood was determined not by geography, linguistic issues, or any preexisting political structure. The kingdom's emergence as a distinct entity in the Iberian Peninsula was pivoted on a series of political and military events seeking the reclamation of land occupied by Muslims after their invasion in Iberia in 711–716. The Reconquista of the al-Andalus, as Muslims called their conquests in Iberia, is key to understanding the emergence of Portugal as a state. It brought back into Christianity lands that were among the most prosperous in Medieval Europe. At the end of the tenth century, stretching from the river Douro to Gibraltar, al-Andalus had an abundant and diversified agricultural produce, which also enjoyed the reputation of being the most technically sophisticated of the time. Of an estimated population of 10 million, 10 percent lived in cities. It was the western-most part of the Islamic world, which was described at the time as being a series of urban centers, connected by trade routes, lubricated by precious metals, and closely linked to the sub-Saharan empires of Ghana, Mali, and Songhai (Findlay and O'Rourke 2007: 48–59). The al-Andalus “represented a kind of El Dorado or Promised Land” whose resources provided a powerful incentive to the Christian kingdoms of the northern Iberian Peninsula (Chalmeta 1994: 756). Muslim Portugal was part of “Gharb al-Andalus,” the western al-Andalus, and evidence suggests that it was notably from the lower valley of the Tagus to the south that Muslim occupation was more dense and urbanized.
The making of a political entity through conquest of land and capture of resources from the western al-Andalus determined the balance of power among the Crown, the nobility, and the Church, which were the three prominent institutions called to organize new settlements and the exploitation of endowments. The partition of wealth among these entities fostered warfare, not only within the borders, but also, and mainly, beyond frontiers. Thereby the main stages of the Reconquista that pushed the frontiers further to the south and the capture of Ceuta in 1415 that opened up the European expansion are events having common ultimate factors, namely the king's need of legitimizing his rule by redistributing resources and jurisdictional powers that were pegged to the exploitation of land.