Energy shortage, global warming, and climate change led to an increase in the use of alternative sources of energy, with renewable energy sources (RES) playing a fundamental role in this new ...energetic paradigm. However, the investment costs often constitute a major barrier to their spread use. Moreover, the overall benefits of renewable energy technologies are often not well understood and consequently they are often evaluated to be not as cost effective as traditional technologies. From the moment that the energy sector started a deregulation process, with a high level of competitiveness and associated increased market uncertainty, traditional project evaluation techniques alone became insufficient to properly deal with these additional risk and uncertainty factors. The diffusion of the renewable energy technologies is also affected by this feature. The way investors evaluate their investments call now for the use of more sophisticated evaluation techniques. Real options approach can deal with these issues and, as so, began to be considered and applied for the energy sector decision aid. This approach it is now extensively widespread in evaluating investment projects in the energy sector. A large set of applications in almost all fields of energy decision making, from electricity generation technologies appraisal to policy evaluation is available in the literature. However the use of this technique in the field of RES is still limited and worth to be analysed. This paper addresses this issue. A review of the current state of the art in the application of real options approach to investments in non-renewable energy sources and RES is presented, giving perspectives for further research in this field.
Brazil has become an antagonist in natural resource conservation policies in recent years. The Brazilian Cerrado is one of the biomes most affected by this setback due to the occupation of areas of ...economic interest in agriculture. Interestingly, there are projects throughout the biome that aim to encourage the preservation of natural resources, but there is uncertainty about whether these incentives have provided conservation. That is the case of the Feio River hydrographic basin, located in the Cerrado, near the city of Patrocínio, state of Minas Gerais. Indeed, the Feio River watershed has projects incentivizing the Cerrado's conservation. Thus, in this article, we aimed to explain how the advance of agriculture in fragile areas of the Feio river watershed occurs, their causes and whether protection strategies have produced satisfactory results. We used an old Environmental Fragility proposal methodwith our contributions to estimate the variations regarding nature conservation in the basin. Our findings show considerable heterogeneity in the potential fragility of the Feio's river basin. We observe that less fragile sites are used for coffee cultivation (74 and 72% of the two places), while more fragile sites are occupied by reserves (around 50% of the area) and high-impact activities such as traditional monoculture and cattle ranching (25 and 44% for the two sites). Temporally, we observed little change in use and occupation, with a slight increase in no-till farming to replace coffee and conventional cultivation. The permanent preservation areas in the basin have improved vegetation quality, while the reserve areas composed of fields show a degradation process. Considering the importance of the Feio's river basin, different incentives and inspection strategies are needed to guarantee the site's preservation and environmental restoration.
•Environmental protection policies adopted do not seem to have short prize effect for the conservation of areas.•Areas close to rivers show low agricultural potential and are occupied by small farms, with activities of high impact.•Less fragile areas are widely occupied by agriculture, mainly coffee, which causes greater deforestation in denser cerrado.
Plastics are highly durable and widely used materials. Current methodologies of plastic degradation, elimination, and recycling are flawed. In recent years, biodegradation (the usage of ...microorganisms for material recycling) has grown as a valid alternative to previously used methods. The evolution of bioengineering techniques and the discovery of novel microorganisms and enzymes with degradation ability have been key. One of the most produced plastics is PET, a long chain polymer of terephthalic acid (TPA) and ethylene glycol (EG) repeating monomers. Many enzymes with PET degradation activity have been discovered, characterized, and engineered in the last few years. However, classification and integrated knowledge of these enzymes are not trivial. Therefore, in this work we present a summary of currently known PET degrading enzymes, focusing on their structural and activity characteristics, and summarizing engineering efforts to improve activity. Although several high potential enzymes have been discovered, further efforts to improve activity and thermal stability are necessary.
Irene Lisboa (1892–1958) foi uma cronista, ou jornalista literária, que, a partir da voz de personagens reais ou personagens-fonte e da sua própria voz, apresenta um discurso de denúncia do cenário ...sociopolítico, resultado da sua posição imersiva nos locais de observação. Como revistas antirregime, e por isso censuradas, a Seara Nova e a presença, folha de arte e crítica, através dos seus autores, tentaram encontrar meios de resistir e, ao mesmo tempo, denunciar um país, um povo e, consequentemente, uma mulher idealizados. Assim, neste estudo, pretende-se compreender a representação da violência contra a mulher durante a ditadura portuguesa, numa perspetiva discursiva e narrativa, a partir do corpus cronístico de Irene Lisboa, publicado nas revistas Seara Nova e presença, folha de arte e crítica, no período entre 1929 e 1955. As conclusões apontam no sentido de que a autora deixa representada uma mulher vítima de violência exercida pelo Estado, pela família e pela sociedade. A mulher representada por Lisboa é um ser dual. Por um lado, a mulher burguesa que é formada pelo preconceito e pelo servilismo; por outro lado, a mulher do povo, também sujeita às questões de género e de poder que a desumanizam enquanto pessoa e mulher; e ambas longe da mulher idealizada pelo regime.
Abstract
To evaluate the effect of an Escherichia coli lipopolysaccharide (LPS) challenge on the digestible lysine (Lys) requirement for growing pigs, a nitrogen (N) balance assay was performed. ...Seventy-two castrated male pigs (19 ± 1.49 kg body weight BW) were allocated in a 2 × 6 factorial design composed of two immune activation states (control and LPS-challenged) and six dietary treatments with N levels of 0.94, 1.69, 2.09, 3.04, 3.23, and 3.97% N, as fed, where Lys was limiting, with six replicates and one pig per unit. The challenge consisted of an initial LPS dose of 30 μg/kg BW via intramuscular (IM) injection and a subsequent dose of 33.6 μg/kg BW after 48 h. The experimental period lasted 11 d and was composed of a 7-d adaptation and a subsequent 4-d sampling period in which N intake (NI), N excretion (NEX), and N deposition (ND) were evaluated. Inflammatory mediators and rectal temperature were assessed during the 4-d collection period. A three-way interaction (N levels × LPS challenge × time, P < 0.05) for IgG was observed. Additionally, two-way interactions (challenge × time, P < 0.05) were verified for IgA, ceruloplasmin, transferrin, haptoglobin, α-1-acid glycoprotein, total protein, and rectal temperature; and (N levels × time, P < 0.05) for transferrin, albumin, haptoglobin, total protein, and rectal temperature. LPS-challenged pigs showed lower (P < 0.05) feed intake. A two-way interaction (N levels × LPS challenge, P < 0.05) was observed for NI, NEX, and ND, with a clear dose–response (P < 0.05). LPS-challenged pigs showed lower NI and ND at 2.09% N and 1.69 to 3.97% N (P < 0.05), respectively, and higher NEX at 3.23% N (P < 0.05). The parameters obtained by a nonlinear model (N maintenance requirement, NMR and theoretical maximum N deposition, NDmaxT) were 152.9 and 197.1 mg/BWkg0.75/d for NMR, and 3,524.7 and 2,077.8 mg/BWkg0.75/d for NDmaxT, for control and LPS-challenged pigs, respectively. The estimated digestible Lys requirements were 1,994.83 and 949.16 mg/BWkg0.75/d for control and LPS-challenged pigs, respectively. The daily digestible Lys intakes required to achieve 0.68 and 0.54 times the NRmaxT value were 18.12 and 8.62 g/d, respectively, and the optimal dietary digestible Lys concentration may change depending on the feed intake levels. Based on the derived model parameters obtained in the N balance trial with lower cost and time, it was possible to differentiate the digestible Lys requirement for swine under challenging conditions.
The electricity market in Brazil is basically organized under two parts: the regulated market, where energy is traded through auctions, and the free market, where market participants freely negotiate ...the price and quantity of electricity. Although revenues obtained in the regulated market tend to be lower than in the free market, the auctions’ results show that investors still value the lesser degree of uncertainty associated with the regulated market. However, a growing interest in the free market by investors is recognized since the price of electricity tends to be higher. Therefore, this study investigates four free market price scenarios to assess the expected return for investors, using the traditional discounted cash flow approach complemented with Monte Carlo simulation to address market uncertainty. The study breaks new ground by capturing the weekly price fluctuations and including the price elasticity of demand of the free market. The results seem to indicate that the disclosure of the ceiling and floor price limits for the spot price can signal important information about the agents’ price expectation in the free market and can be used for investment project evaluation.
The domesticated grapevine spread along the Mediterranean basin from the primary Near East domestication area, where the greatest genetic diversity is found in its ancestor, the wild vine ...populations. Portuguese wild populations are on the southwestern fringe of the distribution of the
L. ssp
in Europe. During the last Glacial Period they became isolated from the previous continuum that had been the territory of wild vine populations. Archaeological remains of domesticated
grapevines in Portugal date back from 795 Before Common Era (BCE) in the lower Tagus river basin. In this work, 258 Portuguese
varieties and
plants were characterized using 261 single nucleotide polymorphism (SNP) markers. The study of the genetic diversity of this local germplasm, its population structure and kinship, all framed in their historical and geographical backgrounds, revealed a complex network of first-degree relationships, where only Iberian varieties are involved. Some Iberian genotypes, like Alfrocheiro (Bruñal, in Spain), Sarigo (Cayetana Blanca), Mourisco Branco (Hebén), Amaral (Caiño Bravo), and Marufo (Moravia Dulce) are ancestors of a considerable fraction of all the autochthonous analyzed varieties. A part of the diversity developed was mostly local in some cases as shown by the closeness of several varieties (Vinhos Verdes) to the wild cluster in different analyses. Besides, several evidences of introgression of domesticated germplasm into wild vines was found, substantiating the high risk of genetic contamination of the
subspecies. All these findings together to the known matching between the wild maternal lineage of the Iberian Peninsula and an important number of Portuguese grapevine varieties (chlorotype A), point out that some of these varieties derive, directly or indirectly, from originally local wild populations, supporting the possible occurrence of secondary events of local domestication, or, at least, of an introgression process of wild into cultivated grapevines.
The importance of macroeconomic indicators on the performance of bankruptcy prediction models has been a contentious issue, due in part to a lack of empirical evidence. Most indicators are primarily ...centered around a company's internal environment, overlooking the impact of the economic cycle on the status of the company. This research brings awareness about the combination of microeconomic and macroeconomic factors. To do this, a new model based on logistic regression was combined with principal component analysis to determine the indicators that best explained the variations in the dataset studied. The sample used comprised data from 1,832 Portuguese construction companies from 2009 to 2019. The empirical results demonstrated an average accuracy rate of 90% up until three years before the bankruptcy. The microeconomic indicators with statistical significance fell within the category of liquidity ratios, solvency and financial autonomy ratios. Regarding the macroeconomic indicators, the gross domestic product and birth rate of enterprises proved to increase the accuracy of bankruptcy prediction more than using only microeconomic factors. A practical implication of the results obtained is that construction companies, as well as investors, government agencies and banks, can use the suggested model as a decision-support system. Furthermore, consistent use can lead to an effective method of preventing bankruptcy by spotting early warning indicators.
Selenium (Se) has been recognized as an essential micronutrient for nearly all forms of life. In recent decades, broiler responses to dietary Se supplemental levels and sources have received ...considerable attention. On environmental grounds, organic trace mineral utilization in practical broiler feeds has been defended due to its higher bioavailability. In such feeds, trace minerals are provided simultaneously in the same supplement as inorganic salts or organic chelates, a fact commonly ignored in assays conducted to validate organic trace mineral sources. The current assay aimed to investigate growth and biochemical responses, as well as Se retention of growing chicks fed diets supplemented with organic and inorganic Se levels and where the trace minerals (zinc, copper, manganese, and iron) were provided as organic chelates or inorganic salts according to Se source assessed. In so doing, a 2 × 5 factorial arrangement was used to investigate the effects of sodium selenite (SS) and selenium-yeast (SY) supplemented in feeds to provide the levels of 0, 0.08, 0.16, 0.24, and 0.32 mg Se/kg.
Chicks fed selenium-yeast diets had body weight (BW), and average daily gain (ADG) maximized at 0.133 and 0.130 mg Se/kg, respectively. Both Se sources linearly increased (P < 0.05) the glutathione peroxidase (GSH-Px) activity in chick blood but higher values were observed in sodium selenite fed chicks (P < 0.05). Both Se sources influenced thyroid hormone serum concentrations (P < 0.05). Chicks fed SY exhibited greater retention of Se in the feathers (P < 0.05). Relative bioavailability of selenium yeast compared with SS for the Se content in carcass, feathers, total and Se retention were, 126, 116, 125 and 125%, respectively. SY supplementation resulted in lower liver Se concentration as Se supplementation increased (P < 0.05).
Based on performance traits, the supplemental level of organic Se as SY in organic trace minerals supplement to support the maximal growth of broiler chicks is 0.133 mg Se/kg.
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