469 research outputs found
Google Earth Engine based monitoring of cork and holm oak woodlands NDVI trends in Portugal
ComunicaçãoThe Mediterranean area currently suffers a general decline of oak woodlands’ health and productivity. Cork oak (Quercus suber L.) and holm oak (Quercus ilex L.) are widely exploited in Portugal and are an important economical and ecological resource for the country. The Normalized Difference Vegetation Index (NDVI) is a common remote sensing index used as a proxy for vegetation biomass, chlorophyll activity, health and stress. NDVI can be monitored for 34 years (1984-2017) at 30-meter of resolution using Landsat imagery. The online platform Google Earth Engine (GEE) allows the free access and fast handling of this huge amount of satellite images. Objective: Providing to researchers, land owners and policy-makers a high-resolution map of cork and holm oak long-term trends for the whole PortugalN/
Avaliação da exposição ocupacional a vibrações transmitidas ao sistema corpo inteiro: estudo preliminar em motoristas de pesados de mercadorias
As vibrações transmitidas ao corpo inteiro (VCI) são um agente físico que afecta os condutores de camiões e apresenta consequências para a sua saúde, estando fortemente associada à dor lombar. No presente estudo seleccionou-se um motorista que conduz um veículo pesado de mercadorias com classificação N3 e que efectua rotas de pequeno curso no Norte de Portugal. As medições realizaram-se em dois dias representativos da actividade semanal, em duas rotas distintas (Rota 1 e 2), de acordo com a metodologia definida no Decreto-Lei n.º 46/2006 de 24 de Fevereiro e na NP ISO 2631-1 de 2007. Foi utilizado um analisador de vibrações, sendo o acelerómetro triaxial fixado ao assento do veículo, de forma a quantificar a aceleração eficaz nos três eixos ortogonais x, y e z. Complementarmente ao processo de amostragem, aplicou-se um questionário a sete motoristas. Os resultados demonstram a dominância da direcção vertical (z) com picos de aceleração na frequência de 1,6Hz. A degradação do piso e a ausência de carga do veículo foram identificados como factores responsáveis pelo aumento dos níveis vibracionais. Relativamente à exposição do trabalhador, obteve-se valores de A(8) Rota 1 de 0,22 m/s2 e A(8) Rota 2 de 0,14 m/s2, sendo o A(8) semanal de 0,19 m/s2, verificando-se que os valores obtidos são inferiores ao valor de acção de exposição preconizado na legislação nacional (0,5m/s2). Quanto aos sintomas manifestados pelos motoristas destacam-se: dor lombar (43%), fadiga (71%), irritabilidade (57%) e dores de cabeça (57%). Apesar dos valores obtidos evidenciarem que o trabalhador não se encontra exposto, segundo o preconizados na legislação, devem ser implementadas medidas que visem a manutenção e conservação dos pisos das vias, manutenção dos veículos e elaboração de planos de formação que abordem o tipo de condução e as posturas a adoptar para salvaguarda do bem-estar e conforto dos trabalhadores.info:eu-repo/semantics/publishedVersio
Noise Reduction and Control in Hospital Environment: Design of the NeoNoise Project
The “NeoNoise Project: Integrated Approach to Minimize Sound Pressure Levels in Neonatal Intensive Care Units” is being conducted by the Research Group on Occupational and Environmental Health of the Research Center on Health and Environment in neonatal intensive care units, since exposure to sound pressure levels in these spaces has been recognized as a factor that influences the quality and well‐being of the occupants (workers and others), as well as the recovery of premature infants who are hospitalized. This work reports the rationale and the design of the NeoNoise project as well as the methods used for data collection. A brief review on the results published and available for the scientific community is also made. In general, NeoNoise project intends to make an integration of all relevant factors, with the intention of presenting a guiding document to change the working practices and occupant\u27s behaviors. So far, this study provided data on sound pressure levels by objective and subjective approaches, as well as information about the exposure factors and sensitivity of the occupants to noise
Development of cellulose acetate membranes containing nanoparticles for water applications
The growth of human population and inherent activities, the improper industrialization practices, the direct
addition of materials TO the waterway, and the excessive use of fertilizers containing phosphates to increase
the production of crops are the main sources for the high input of phosphates in water bodies. These effects
have been causing eutrophication, and bacterial contamination of the water. In fact, the bacteria present in the
water can cause harmful disease, sickness or other problems to the human being. Moreover, the excess of
phosphates in the aquatic system induces excessive growth of plants, which consume oxygen of the water
body, thereby creating the state of hypoxia, which causes a reduction in specific fish and other animals.
Therefore, the removal of phosphates from eutrophic waters and bacteria are crucial to avoid health problems,
especially near urban areas[1].
The most common way to purify water is through membrane separation processes, in fact, cellulose acetate
(CA) membranes have been used for reverse osmosis membranes [2] for converting impaired water into
fresh-water. However, several components can be incorporated into cellulose structure to allow the
development of membranes for different applications[3].
The present work aims to develop a hybrid membrane based on CA with embedded silver and/or aluminium
nanoparticles, for the remediation of contaminated aquatic environments with microorganism, which can also
be used for removal of water contaminated with phosphate ion. Therefore, CA membranes were obtained by
solution casting, where silver and/or aluminium nanoparticles were chemical reduced in-situ. Silver
nanoparticles (Ag-NPs) were synthesized using silver nitrate and sodium borohydride as reducing agent.
Otherwise, aluminium nanoparticles (Al-NPs) were obtained using aluminium isopropoxide as the starting
precursor in the presence of acid.
The detection of Al-NPs in the membranes was carried out by FTIR spectra analysis, which showed that Al-O
bonds were formed between the aluminium precursor and the CA. The study of phosphorus adsorption kinetics
in membranes with embedded Al-NPs were proven to be efficient for the removal of phosphorus. This
membrane showed considerable ability to remove phosphate ions from aqueous solutions at low aluminium
nanoparticle content into the CA/Ag-NPs matrices. In-situ the developed membranes showed good
antimicrobial behaviour preventing the growth of microorganisms. The results indicate that the synthesized
CA/Ag-NPs/Al-NPs membranes could have potential to be used in the remediation of water resources
Vascularization approaches in tissue engineering: recent developments on evaluation tests and modulation
This review focuses on vascularization and strategies involved in its evaluation
and modulation. Clinical issues associated with engineered tissues of an atomically relevant size
that require a vascular network to supply their cells with nutrients and oxygen are analyzed in
terms of vascular network formation within scaffolds, which can be produced from varying
biomaterials, with the capability of connecting to the vasculature of the patient. Developing
angiogenesis techniques and monitoring of angiogenesis development as well as how these
methods can be further utilized to tailor vascularization within large tissue engineered
constructs are also discussed. Finally, we offer a glimpse toward the future by providing an
outlook for vascularization and associated emerging bioprinting concepts in tissue engineering
applications.The authors acknowledge the financial support provided through the projects B-FABULUS (PTDC/BBB-ECT/2690/2014) and Fun4TE (PTDC/EMD-EMD/31367/2017), financed by the Portuguese Foundation for Science and Technology (FCT) and cofinanced by European Regional Development Fund (FEDER) and Operational Programme for Competitiveness and Internationalisation (POCI). This work was also partly supported by H2020-MSCA-RISE BAMOS project, funded from the European Union's Horizon 2020 research and innovation program under Grant Agreement No. 734156. S.V.L. acknowledges FCT for the PhD grant (SFRH/BD/143954/2019). The FCT distinction attributed to J.S.-C. (IF/00115/2015) under the Investigator FCT program is also greatly acknowledged
Rheological and functional evaluation of the interactions between bitumen and rubber
It is estimated that about ten kilograms of tires are discarded per inhabitant
annually. The negative impact of this residue can be reduced, since rubber can be reused as a
constituent of asphalt rubber (AR) binder in road pavements. However, the materials which
constitute the AR binders and their interaction are not sufficiently characterized. In this work
several base bitumens interacted with crumb rubber, in order to produce AR binders, which
were subsequently separated, by using a modified “Basket drainage method” to recover the
residual bitumen and rubber. EN 12591 or 14023 standards tests and the Dynamic Shear
Rheometer (DSR) were used to evaluate the changes in the properties of the binders during
AR production. The swelling and depolymerisation changes in the rubber were evaluated
through microscopic tests. It was observed that the characteristics of the base bitumen significantly
affect the rubber and the AR binder properties (mainly for interactions with softer
bitumens)
Knee surgery complications related to biomaterials
Recent years have seen a growing interest in biomaterials and use of these materials in the clinical setting is increasing. Despite their advantages, they have also been cited as the source of specific complications and/or fail- ures. Problems such as screw breakage, tunnel enlargement, allergic or foreign body reactions, cyst and abscess formation, or even delayed migration of supposedly biodegradable screws/implants have been reported. This chapter aims to review the basic science and clinical experience with biomaterials currently employed in fixation devices for knee surgery. Information on the clinical implications of biodegradable screws is still limited. Surgeons tend to focus more on the emerging successes of innovations than on the complications and failures (publication bias) of older devices, making it difficult to reliably assess the incidence of such events. More- over, the complexity of possible reactions occurring in the human body cannot be reproduced under controlled laboratory conditions.Neverthe- less, surgeons and patients must be aware of both the advantages and the complications of these devices. Only in this way can informed choices be made, so that both parties are prepared to face and overcome the unde- sired complications, and the improvement of future implants can become a reality
Бедий эсер талилининъ принциплери ве усуллары меселесине даир
В предложенной статье представлен теоретический материал, который раскрывает вопросы, связанные с принципами и методами анализа художественного произведения, подкреплённый необходимым материалом из крымскотатарской литературы.У запропонованій статті представлений теоретичний матеріал, що розкриває питання, пов'язані із принципами й методами аналізу художнього твору, підкріплений необхідним матеріалом із кримськотатарської літератури.In offered(suggested) clause(article) the theoretical material which opens the questions connected to principles and methods of the analysis of a work of art, supported by a necessary material from крымскотатарской literatures is submitted
TCTEX1D4, a novel protein phosphatase 1 interactor: connecting the phosphatase to the microtubule network
Reversible phosphorylation plays an important role as a mechanism of intracellular control in eukaryotes. PPP1, a major eukaryotic Ser/Thr-protein phosphatase, acquires its specificity by interacting with different protein regulators, also known as PPP1 interacting proteins (PIPs). In the present work we characterized a physiologically relevant PIP in testis. Using a yeast two-hybrid screen with a human testis cDNA library, we identified a novel PIP of PPP1CC2 isoform, the T-complex testis expressed protein 1 domain containing 4 (TCTEX1D4) that has recently been described as a Tctex1 dynein light chain family member. The overlay assays confirm that TCTEX1D4 interacts with the different spliced isoforms of PPP1CC. Also, the binding domain occurs in the N-terminus, where a consensus PPP1 binding motif (PPP1BM) RVSF is present. The distribution of TCTEX1D4 in testis suggests its involvement in distinct functions, such as TGFβ signaling at the blood-testis barrier and acrosome cap formation. Immunofluorescence in human ejaculated sperm shows that TCTEX1D4 is present in the flagellum and in the acrosome region of the head. Moreover, TCTEX1D4 and PPP1 co-localize in the microtubule organizing center (MTOC) and microtubules in cell cultures. Importantly, the TCTEX1D4 PPP1BM seems to be relevant for complex formation, for PPP1 retention in the MTOC and movement along microtubules. These novel results open new avenues to possible roles of this dynein, together with PPP1. In essence TCTEX1D4/PPP1C complex appears to be involved in microtubule dynamics, sperm motility, acrosome reaction and in the regulation of the blood-testis barrier
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