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This paper aims to investigate coconut fiber’s thermal behavior and evaluate its potential energy production through kinetic and thermodynamic studies, as well as the potential to produce solid biofuels (briquettes). Structural chemical analysis, proximate analysis, and higher heating value characterized coconut fiber. The thermogravimetric experiments were carried out in an inert atmosphere (N2), varying the heating rates at 5, 10, 15, and 20 K min−1. The kinetic triplet was determined using isoconversional methods and master plot methodology. The pre-exponential factor, enthalpy, entropy, and Gibbs free energy parameters were calculated. The briquettes were made by different particle sizes: mixed particles (without granulometric classification); particles between 0.35 mm and 0.25 mm, and particles lower than 0.25 mm. The coconut fiber briquettes were produced in a compaction system at a temperature of 393.15 K under 15 MPa pressure for 20 min. This study also determined the apparent density, the resistance to diametral compression, and the energy density for coconut fiber briquettes. The pyrolysis reaction was modeled considering the reaction mechanism of as the three-dimensional Jader equation, with global activation energy 129.8 kJ mol−1and global pre-exponential factor 2.68 × 107 s−1. The enthalpy and entropy values have shown considerable variations due to the conversion, suggesting that the pyrolysis of coconut fiber involves complex reaction mechanisms. The briquetting process enhanced the coconut fibers, and the results have shown that the lower particle size (particles ≤ 0.25 mm) presented better physical–mechanical properties and energy density. It is concluded that coconut fiber has the potential to be turned into biofuels from the thermochemical processes and may be enhanced by the densification process.

Yeasts can play important roles in promoting plant growth; however, little information is available in this regard for yeasts in water of bromeliad tanks. Here, we characterize the ability of 79 yeast isolates from tank bromeliad Vriesea minarum, an endangered species, to solubilize phosphate, secrete siderophores, and synthesize indole-3-acetic acid (IAA). The results showed that 67.8% of all assayed yeast isolates mobilized inorganic phosphate; 40.0% secreted siderophores; and 89.9% synthetized IAA and IAA-like compounds. Among the species studied, Carlosrosaea vrieseaeUFMG-CM-Y6724 is highlighted for producing IAA (76.1 μg mL−1) and siderophores, and solubilizing phosphate. In addition, evaluation of the effects of filtrate containing IAA-like compounds produced by the C. vrieseaeon the development and photosynthetic performance of V. minarumseedlings found it to improve seedling growth equal to that of commercial IAA. These results demonstrate that C. vrieseaecan produce compounds with great potential for future use as biofertilizer agents.

The austerity policies implemented in Portugal because of the bailout agreement between the Portuguese Government and the Troika include measures to increase performance and reduce costs. An analysis of local government efficiency and an assessment of its determinants is highly relevant for policy purposes, particularly when new efforts to decentralize are being discussed. The aim of this research is to evaluate the efficiency of the 278 mainland municipalities in Portugal using a two-stage procedure, combining data envelopment analysis in the first phase with fractional response models in the second. The analysis is performed for 2010 and 2015, beforeand afterthe Troika’s intervention in Portugal. Results show a similar pattern for both years, in the two stages. The results also indicate that there is no structural changes from 2010 to 2015, suggesting that the reforms implemented in municipalities did not succeed.

Purpose: This study aims to explore the firm’s and country-level institutional forces that determine banks’ CSR reporting diversity, during the recent global financial crisis. Design/methodology/approach: Specifically, this study assesses whether economic and institutional conditions explain CSR disclosure strategies used by 30 listed and unlisted banks from six countries in the context of the recent 2007/2008 global financial crisis. The annual reports and social responsibility reports of the largest banks in Canada, the UK, France, Italy, Spain and Portugal were content analyzed. Findings: The findings suggest that economic factors do not influence CSR disclosure. Institutional factors associated with the legal environment, industry self-regulation and the organization’s commitments in maintaining a dialogue with relevant stakeholders are crucial elements in explaining CSR reporting. Consistent with the Dillard et al.’s (2004) model, CSR disclosure by banks not only stems from institutional legitimacy processes, but also from strategic ones. Practical implications: The findings highlight the importance of CSR regulation to properly monitor manager’s’ opportunistic use of CSR information and regulate the assurance activities (regarding standards, their profession or even the scope of assurance) to guarantee the proper credibility reliability of CSR information. Originality/value: The study makes two major contributions. First, it extends and modifies the model used by Chih et al.(2010). Second, drawn on the new institutional sociology, this study develops a theoretical framework that combines the multilevel model of the dynamic process of institutionalization, transposition and deinstitutionalization of organizational practices developed by Dillard et al.(2004) with Campbell’s (2007) theoretical framework of socially responsible behavior. This theoretical framework incorporates a more inclusive social context, aligned with a more comprehensive sociology-based institutional theory (Dillard et al., 2004; Campbell, 2007), which has never been used in the CSR reporting literature hitherto.

The lignocellulosic biomass is a renewable alternative for fossil fuels. The extensive cultivation of coffee grounds in Brazil generates a large amount of residues, as coffee husks. The work aimed at performing the coffee husks characterization, investigating the viability for fast pyrolysis application. Coffee husks were dried, grinded in a knives mill and sieved using a mechanical sieving; different vibration frequencies and times were used to evaluate the effect of these variables in the size distribution. The true density was inferred for three distinct size ranges of the coffee husks, using a helium pycnometer. Proximate and ultimate analyses were performed. The analytical pyrolysis was realized at 550°C, using a micro pyrolyzer (CDS 5200), vapors was identified by a gas chromatograph and a mass spectrometer (GC-MS QP 2010 plus, Shimadzu). The influence of the particles irregular shape was evidenced in the results of size distribution. The values of true density were around 1.5 g/cm3. The smaller the particle size, the higher the true density of the sample. Coffee husks can be used to generate high added value compounds: 1,3 pentadiene, limonene and n-hexadecanoic acid. Considering the use of coffee husks bio-oil as a fuel, results indicated that the bio-oil will present high calorific value, important acidity and smaller increases in viscosity and molecular weight if compared to the bio-oil of other lignocellulosic materials.

There is a growing interest in new technologies for power generation, making use of renewable natural resources. Fast pyrolysis is an effective and promising process of thermal decomposition of organic materials. This study evaluated the thermal decomposition of three different types of lignin and investigated the composition of the volatiles formed during the analytical pyrolysis. The thermogravimetric analysis, which is a widely used analytical technique to observe the thermal behavior of materials, was used to investigate the decomposition of the samples at different heating rates. The micropyrolysis is a fast and reliable analytical technique that provides useful background information for development of the complex process production of bio-oil. This study evaluated the composition of the vapor formed during analytical pyrolysis at 450, 550 and 650°C. The curves obtained by thermogravimetric analysis indicate the degradation of all lignin samples takes place in a wide temperature range. Analytical pyrolysis tests for three types of lignin showed formation of phenolic compounds as most significant components.

Objective: Defects in the human thyroid peroxidase (TPO) gene are reported to be one of the causes of congenital hypothyroidism (CH) due to a total iodide organification defect. The aim of the present study was to determine the nature and frequency of TPO gene mutations in patients with CH, characterised by elevated TSH levels and orthotopic thyroid gland, identified in the Portuguese National Neonatal Screening Programme.Subjects and methods: The sample comprised 55 patients, from 53 unrelated families, with follow-up in the endocrinology clinics of the treatment centres of Porto and Lisbon. Mutation screening in the TPO gene (exons 1–17) was performed by single-strand conformational analysis followed by sequencing of fragments with abnormal migration patterns.Results: Eight different mutations were detected in 13 patients (seven homozygotes and six compound heterozygotes). Novel mutations included three missense mutations, namely 391T > C (S131P), 1274A > G (N425S) and 2512T > A (C838S), as well as the predictable splice mutation 2748G > A (Q916Q/spl?). The undocumented polymorphism 180-47A > C was also detected.Conclusion: The results are in accordance with previous observations confirming the genetic heterogeneity of TPO defects. The proportion of patients in which the aetiology was determined justifies the implementation of this molecular testing in our CH patients with dyshormonogenesis.

In this study we have examined the responses ofHevea plants to low temperatures in growth chambers simulating winter conditions in the tropics. The low temperatures increased the leaf diffusive resistance even with a rise in the leaf temperatures toward the end of day. The total chlorophyll levels were reduced by chilling, with no changes in the chlorophyll a/b ratio. Neither organic solute nor electrolyte leakage were observed at low temperatures. These results explain the low growth rate of plants and the lack of serious chilling symptoms (necrosis) in mature leaves during winter conditions near latitude 22° S in Brazil.

Abstract:  The aim of this study was to verify the applicability of a heat-sum model and an alternative model that included photoperiod to describe Hevea bud growth. Considering 19° C as the base temperature, approx. 172 degree days were required for bud growth up to leaf blade expansion. The applicability of the heat-sum model for Hevea bud growth was confirmed. The inclusion of day length as an exponential term in accumulated degree days resulted in the model fitting much better for the spring than for the winter conditions.

In this study we determined the base temperature and Heat units for leaf flushing initiation and growth of RRIM-600 and GT1Hevea clones. The minimum base temperature was found to be approximately 16° C for leaf flushing emission and 19° C for shoot growth in terms of height. Approximately 420 degree days at 16° C as base temperature is required for successive leaf flushing initiation. Linear equations with correlation coefficients above 0.95 allow an estimation of the height increase from the accumulated degree days, corrected or otherwise for photoperiod. The highest correlation coefficients demonstrated a positive effect of the photoperiod among the factors influencing the shoot growth.