3,970 research outputs found
Forest vintages and carbon sequestration
In the current paper we examine the role of forest carbon sequestration benefits in optimal forest management. When carbon benefits are considered not only the forested area is relevant, but also the flow of carbon between land and the atmosphere through the carbon cycle. To account for all these impacts a multi-vintage forest setting is used, following Salo and Tahvonen (2004). The model is extended to three different carbon accounting methods to measure the benefits form carbon sequestration: carbon flow regime, tonne-year crediting and average storage. In the case of the carbon flow regime, the impact on the optimal management and allocation of land will depend upon the amount of carbon released when the forest is harvested. Under the other two accounting systems optimal steady state forest area will be increased, and in cases where optimal management imply cyclical harvesting, considering carbon benefits will always increase cycles dimension.
The Hyperbolic Forest Owner
This paper examines the implications of quasi-hyperbolic inter-temporal preferences to the Faustman model. The use of decreasing discount rates leads to dynamically inconsistent behavior. To solve this problem a two-stages optimization decision model is developed. The resulting actual cutting time will be anticipated compared to the Faustman optimal cutting time. If, alternatively, the equivalent constant rate of discount is the empirically observed discount rate, then the optimal cutting time is the same, but the present value of profits for the hyperbolic forest owner is always higher than the one resulting from the equivalent constant discount rate. All these results apply to both the single and the multiple rotation problems.Hyperbolic discounting; time preference; dynamic inconsistency; Faustman model; optimal rotation
Ethics and deontology of medical education and nurses in Portugal
This article discusses deontological issues of health care professions in relation to their ethical foundation. We present four models of teaching ethics and deontology in doctors’ training and the results of a PhD research on the teaching of these subjects in nurses’ training in Portugal. Given the importance of bioethics in deontological training of health care professions, we present a comparative analysis of. bioethical principles enunciated by Beauchamp and Childress (1979), related to ‘ethics of justice’, and Kemp’s(2000) proposal, associated to an ‘ethics of care’. Given the ambiguity of these bioethical expressions, we focus on the analysis of its contents and the need to discuss the fundamentals of ethical training of doctors and nurses in relation to the ethical theories they are derived from. Utilitarian ethics, duty ethics, virtue ethics, when the analysis of bioethics’ fundaments is not trained, the duty of caring of suffering can be put at risk
Recovery of catalytic metals from leaching solutions of spent automotive catalytic converters using plant extracts
This study investigates the potential of hydroalcoholic extracts of Cistus ladanifer L., Erica Andevalensis and Rubus idaeus L. as a green method for the recovery of platinum group metals (PGMs) from both synthetic unimetallic solutions and multimetallic solutions obtained from the leaching of two different spent automotive catalytic converters (SACC). Experiments with unimetallic solutions revealed that E. andevalensis and R. idaeus extracts could separate about 70% of Pd and less than 40% of other tested metals (Al, Ce, Fe and Pt) from the solutions. Then, application of the plant extracts to two different SACCs leachates showed that E. andevalensis and R. idaeus extracts can induce high precipitation (> 60%) of Pd and Pt with co-precipitation of less than 20% of other metals. UV-Visible spectra analysis confirmed the bio-reduction of Pd2+ ions into Pd-0 nanoparticles by R. idaeus extract, and Fourier transform infrared spectroscopy (FTIR) analysis revealed the contribution of functional groups of the phytochemicals present in the extract (such as phenols, flavonoids and anthocyanins) in the Pd2+ bio-reduction and stabilization. Afterward, scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDX) analysis of the precipitate obtained from one leachate with R. idaeus extract demonstrated the presence of Pd particles along with organic compounds and particles containing other metals. Therefore, particles were subjected to a washing step with acetone for further purification. Finally, scanning transmission electron microscopy with energy dispersive X-ray spectroscopy (STEM-EDX) analysis showed the high purity of the final Pd particles and high-resolution STEM allowed to determine their size variation of 2.5 to 17 nm with an average Feret size of 6.1 nm and confirmed their crystalline structure with an interplanar lattice distance of similar to 0.22 nm. This green approach offers various benefits including simplicity of Pd separation from the leachates as valuable nanoparticles that makes the process more feasible from economic and environmental standpoints. A process cost of similar to 20 $/g of Pd particles recovered was estimated (excluding manpower).LA/P/0101/2020; CRESC Algarve 2020) through Portugal 2020 and European Regional
Development Fund (FEDER), under the project METALCHEMBIO
(no. 29251).info:eu-repo/semantics/publishedVersio
Application of urea-agarose gel electrophoresis to select non-redundant 16S rRNAs for taxonomic studies: palladium(II) removal bacteria
The 16S ribosomal RNA (rRNA) gene has been the most commonly used sequence to characterize bacterial communities. The classical approach to obtain gene sequences to study bacterial diversity implies cloning amplicons, selecting clones, and Sanger sequencing cloned fragments. A more recent approach is direct sequencing of millions of genes using massive parallel technologies, allowing a large-scale biodiversity analysis of many samples simultaneously. However, currently, this technique is still expensive when applied to few samples; therefore, the classical approach is still used. Recently, we found a community able to remove 50 mg/L Pd(II). In this work, aiming to identify the bacteria potentially involved in Pd(II) removal, the separation of urea/heat-denatured DNA fragments by urea-agarose gel electrophoresis was applied for the first time to select 16S rRNA-cloned amplicons for taxonomic studies. The major raise in the percentage of bacteria belonging to genus Clostridium sensu stricto from undetected to 21 and 41 %, respectively, for cultures without, with 5 and 50 mg/L Pd(II) accompanying Pd(II) removal point to this taxa as a potential key agent for the bio-recovery of this metal. Despite sulfate-reducing bacteria were not detected, the hypothesis of Pd(II) removal by activity of these bacteria cannot be ruled out because a slight decrease of sulfate concentration of the medium was verified and the formation of PbS precipitates seems to occur. This work also contributes with knowledge about suitable partial 16S rRNA gene regions for taxonomic studies and shows that unidirectional sequencing is enough when Sanger sequencing cloned 16S rRNA genes for taxonomic studies to genus level.info:eu-repo/semantics/publishedVersio
Growth, photosynthetic pigments, phenolic content and biological activities of Foeniculum vulgare Mill., Anethum graveolens L. and Pimpinella anisum L. (Apiaceae) in response to zinc
The effect of zinc (Zn) on phenols, antioxidant activities (free radicals' scavenging activities, inhibition of lipid peroxidation, chelating activity and reducing power), and enzyme inhibition activities of acetylcholinesterase, lipoxygenase and tyrosinase of anise, dill and two cultivars of fennel [Latina" (F-L) and "Doux de Florence" (F-DF)] aqueous extracts was evaluated for the first time. At the same time, growth and photosynthetic pigment contents were also estimated. A significant decrease in all growth parameters, such as plant height, fresh and dry weights of aerial parts and roots was statistically proved in the presence of 2 mM Zn. An enhancement of Zn accumulation was observed, particularly in aerial part. Exposure to 2 mM Zn induced quantitative changes in the phenols of all tested extracts. In fennel extracts, a decrease of phenol content was observed when treated with Zn, whereas an increase was found in dill and anise extracts submitted to Zn treatment. All samples, either in the presence or absence of Zn, showed antioxidant activity, independent on the tested assay, with the exception of the cultivar F-DF (treated and non-treated), which was unable to scavenge NO radicals. Zn-treated dill and anise presented usually higher antioxidant activity. Concerning inhibitory activities against acetylcholinesterase, lipoxygenase and tyrosinase enzymes, both treated and non-treated F-DF did not inhibit acetylcholinesterase activity. Zinc-treated F-DF was also unable to inhibit lipoxygenase activity. The remaining species presented capacity for inhibiting those enzymes and tyrosinase as well, but their abilities varied in response to Zn excess.Portuguese National Funding Agency for Science, Research and Technology (Fundacao para a Ciencia e a Tecnologia - FCTPortugal) [UID/BIA/04325/2013-MEDTBIO, UID/Multi/04326/2013]info:eu-repo/semantics/publishedVersio
Searching for chemical elements: a multidisciplinary activity in the 150th anniversary of the Periodic Table of Chemical Elements
[Excerpt] 2019 is the 150th anniversary of
the Periodic Table of Chemical Elements and
has therefore been proclaimed the
"International Year of the Periodic Table of
Chemical Elements (IYPT2019)" by the
United Nations General Assembly and
UNESCO [1].
A working tool very useful to various
professionals and in diverse scientific areas,
this table would not exist if someone had not
distributed and ordered the chemical
elements according to the value of their
atomic weights. The father of the Periodic
Table, the Russian chemist Dmitri Mendeleev
(1834-1907), was so visionary that his Table
allows housing not only the known chemical
elements at that time but also the ones still
unknown that came to be discovered or
synthesized. When we come across this
Table, with so many chemical elements, we
ask ourselves how we use them and where
we can find each of them, in our real world
Continuous versus Discrete Time Forest Management Models with Carbon Sequestration Benefits
Forest literature uses both continous and discrete time models to study forest management problems, and when carbon sequestration benefits are considered, the results obtained in both approaches are not always equivalent. This issue is relevant from a policy point of view if credits are to be allocated to forest owners within the implementation of the Kyoto Protocol. This note explores the impact of different carbon sequestration
accounting methods on both settings. It studies the specific conditions for optimal rotation period and the value of a marginal unit of bare land on a one stand model and compare them with the long run optimal stationary
steady state of a forest vintage model.N/
Forest Vintages and Carbon Sequestration
In the current paper we examine the role of forest carbon sequestration benefits in optimal forest management. When carbon benefits are considered not only the forested area is relevant, but also the flow of carbon between land and the atmosphere through the carbon cycle. To account for all these impacts a multi-vintage forest setting is used, following Salo and Tahvonen (2004). The model is extended to three different carbon accounting methods to measure the benefits form carbon sequestration: carbon flow regime, tonne-year crediting and average storage. In the case of the carbon flow regime, the impact on the optimal management and allocation of land will depend upon the amount of carbon released when the forest is harvested. Under the other two accounting systems optimal steady state forest area will be increased, and in cases where optimal management imply cyclical harvesting, considering carbon benefits will always increase cycles dimension.N/
Avec Orima - Designing the brand identity
The thesis is a document in building the brand image for the authors’ own start-up Avec Orima. It is motivated by the need to take the company from the planning stage to the next very first step of implementing the business – designing the company’s brand identity.
The thesis focused on the process of designing the brand identity. The process began with analysing the company and Finnish target market to have the insights on what the company stands for and wants to achieve. The study then continued to examine the competition in Finnish market and identify the points of differences, in order to establish the brand positioning. Upon understanding the Avec Orima brand and what it stands for, the thesis study integrated the brand identity strategy with design skills to create the basic elements of Avec Orima’s visual brand identity – logotype, typography, colours, look and feel, and imagery.
Using a sample of 57 people, the authors collected data from a survey. Also, data from market research was presented. As predicted, the results justify the authors’ points on the existing behaviours, trends and rising demands in Finnish market. The authors conclude that, despite a limitation in existing customer behaviours at the moment, there are rising awareness and demand for such a service provider like Avec Orima. This conclusion is the foundation for all further studies, which are based on theoretical data, in defining the company, then brand positioning and brand identity design
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