323 research outputs found
Mapping the air pollution impact to reindeer range areas in Pasvik, Northern Norway using satellite imageries
Contribution of a photovoltaic solar system to the energetic sustainability of a Portuguese WWTP
The concerning growth of energy and water demand worldwide presents two major issues that can both be tackled by using renewable energy sources to oppose the energy consumption of wastewater treatment plants (WWTP), while taking advantage of their energy production potentialities. This work deals with the sizing of a photovoltaic system of a medium-sized Portuguese WWTP designed to meet the energy consumption needs, benefitting from the higher levels of irradiance in the country. The goal is to act as a model for future similar projects. The potentiality of producing electricity through cogeneration of biogas, in WWTP’s of activated sludge, needs to be taken into account. In the study case, 70% of the energy consumption needs were covered via cogeneration. This led to the conception of two different scenarios concerning the PV System: the first one covers the total electric needs of the WWTP and the other covers 30%, taking into account that the cogeneration system ensures 70%. During the 25 year-life of the PV System, an average annual performance ratio of 0.805 for scenario 1 and 0.789 for scenario 2 was achieved. Furthermore, the average energy contribution of scenario 1 and 2 was 36.5% and 32.8%, respectively, ensuring 100% of self-sufficiency, when adding the cogeneration contribution
Pulmonary Kaposi sarcoma and disseminated Mycobacterium genavense infection in an HIV-infected patient
We report a case of Kaposi sarcoma (KS) and disseminated infection by Mycobacterium genavense in a 40-year-old HIV-positive man with CD4+ T-cell count 5/µL. He presented with anorexia, diarrhoea, cachexia and multiple firm violaceous nodules distributed over the face, neck and upper and lower extremities. Biopsy of a skin nodule was performed, confirming KS. Immunoperoxidase staining for human herpesvirus 8 was strongly positive. Endoscopic examination revealed erosive duodenopathy. Multiple biopsy samples showed numerous acid-fast bacilli at direct microscopic examination. Real-time PCR (RT-PCR) identified M. genavense. A CT scan showed diffuse pulmonary infiltrates with a 'tree-in-bud' appearance, striking splenomegaly and abdominal lymphadenopathy. A bronchoscopy was performed, revealing typical Kaposi's lesions in the upper respiratory tract. RT-PCR of bronchial aspirate identified M. genavense and Pneumocystis jirovecii. Despite treatment with highly active antiretroviral therapy, antimycobacterial therapy and trimethoprim/sulfamethoxazole, the outcome was fatal
Does colon cancer ever metastasize to bone first? a temporal analysis of colorectal cancer progression
<p>Abstract</p> <p>Background</p> <p>It is well recognized that colorectal cancer does not frequently metastasize to bone. The aim of this retrospective study was to establish whether colorectal cancer ever bypasses other organs and metastasizes directly to bone and whether the presence of lung lesions is superior to liver as a better predictor of the likelihood and timing of bone metastasis.</p> <p>Methods</p> <p>We performed a retrospective analysis on patients with a clinical diagnosis of colon cancer referred for staging using whole-body <sup>18</sup>F-FDG PET and CT or PET/CT. We combined PET and CT reports from 252 individuals with information concerning patient history, other imaging modalities, and treatments to analyze disease progression.</p> <p>Results</p> <p>No patient had isolated osseous metastasis at the time of diagnosis, and none developed isolated bone metastasis without other organ involvement during our survey period. It took significantly longer for colorectal cancer patients to develop metastasis to the lungs (23.3 months) or to bone (21.2 months) than to the liver (9.8 months). Conclusion: Metastasis only to bone without other organ involvement in colorectal cancer patients is extremely rare, perhaps more rare than we previously thought. Our findings suggest that resistant metastasis to the lungs predicts potential disease progression to bone in the colorectal cancer population better than liver metastasis does.</p
Comportamento fisiológico, secagem e armazenamento de sementes florestais nativas.
bitstream/CNPF-2009-09/41479/1/circ-tec127.pd
Children's biological givens, stress responses, language and cognitive abilities and family background after entering kindergarten in toddlerhood
We aimed to investigate stress response regulation, temperament, cognitive and language abilities and family SES in children who entered kindergarten before two years of age. Whilst childrens stress regulatory systems are vulnerable to environmental influences little is known about how temperament and family characteristics impact on stress regulation in early years. Participants were 129 children (age 7 to 23 months) from 29 kindergartens. Stress response regulation was assessed by measuring salivary cortisol and alpha-amylase activity. Cognitive and language abilities were assessed using Bayley-III and children temperament with ECBQ-questionnaire. Family characteristics were assessed with surveys. Results suggest that children are alerted during kindergarten day, but their stress response regulation is balanced. Girls and boys differed in cognitive and language abilities. We propose that childrens individual needs should be better acknowledged in kindergartens.Peer reviewe
Ferromagnetic resonance in -Co magnetic composites
We investigate the electromagnetic properties of assemblies of nanoscale
-cobalt crystals with size range between 5 nm to 35 nm, embedded in a
polystyrene (PS) matrix, at microwave (1-12 GHz) frequencies. We investigate
the samples by transmission electron microscopy (TEM) imaging, demonstrating
that the particles aggregate and form chains and clusters. By using a broadband
coaxial-line method, we extract the magnetic permeability in the frequency
range from 1 to 12 GHz, and we study the shift of the ferromagnetic resonance
with respect to an externally applied magnetic field. We find that the
zero-magnetic field ferromagnetic resonant peak shifts towards higher
frequencies at finite magnetic fields, and the magnitude of complex
permeability is reduced. At fields larger than 2.5 kOe the resonant frequency
changes linearly with the applied magnetic field, demonstrating the transition
to a state in which the nanoparticles become dynamically decoupled. In this
regime, the particles inside clusters can be treated as non-interacting, and
the peak position can be predicted from Kittel's ferromagnetic resonance theory
for non-interacting uniaxial spherical particles combined with the
Landau-Lifshitz-Gilbert (LLG) equation. In contrast, at low magnetic fields
this magnetic order breaks down and the resonant frequency in zero magnetic
field reaches a saturation value reflecting the interparticle interactions as
resulting from aggregation. Our results show that the electromagnetic
properties of these composite materials can be tuned by external magnetic
fields and by changes in the aggregation structure.Comment: 14 pages, 13 figure
Transthyretin Promotes Axon Growth via Regulation of Microtubule Dynamics and Tubulin Acetylation
Transthyretin (TTR), a plasma and cerebrospinal fluid protein, increases axon growth and organelle transport in sensory neurons. While neurons extend their axons, the microtubule (MT) cytoskeleton is crucial for the segregation of functional compartments and axonal outgrowth. Herein, we investigated whether TTR promotes axon elongation by modulating MT dynamics. We found that TTR KO mice have an intrinsic increase in dynamic MTs and reduced levels of acetylated a-tubulin in peripheral axons. In addition, they failed to modulate MT dynamics in response to sciatic nerve injury, leading to decreased regenerative capacity. Importantly, restoring acetylated a-tubulin levels of TTR KO dorsal root ganglia (DRG) neurons using an HDAC6 inhibitor is sufficient to completely revert defective MT dynamics and neurite outgrowth. In summary, our results reveal a new role for TTR in the modulation of MT dynamics by regulating a-tubulin acetylation via modulation of the acetylase ATAT1, and suggest that this activity underlies TTR neuritogenic function.This work was supported by: FEDER – Fundo Europeu de Desenvolvimento Regional funds through the COMPETE 2020 – Operacional Programme for Competitiveness and Internationalisation (POCI), Portugal 2020, and by Portuguese funds through FCT – Fundação para a Ciência e a Tecnologia/Ministério da Ciéncia, Tecnologia e Ensino Superior in the framework of the project POCI-01-0145-FEDER-028336 (PTDC/MED-NEU/28336/2017); Norte-01-0145-FEDER-000008 – Porto Neurosciences and Neurologic Disease Research Initiative at I3S, supported by Norte Portugal Regional Operational Programme (NORTE 2020), under the PORTUGAL 2020 Partnership Agreement, through FEDER; and Thompson Family Foundation (TFFI) award, RO1AG050658 (NIH/National Institute on Aging) and R21NS120076 (NIH/NINDS) awards to FB, and a PRIN-2017FJC3-004 (MIUR) to MEP. TM is supported by the Deutsche Forshcunggemeinschaft (EXC 2145 SyNergy – ID 390857198; TRR 274/1 2020 – ID 408885537). JE is a FCT fellow (SFRH/BD/116343/2016). MAL is an FCT Investigator (IF/00902/2015)
Avaliação do cálculo da resistência ao punçoamento centrado de lajes fungiformes reforçadas com fibras de aço : modelos teóricos
Desde 1979 que as fibras de aço vêm sendo estudadas como uma alternativa de reforço às estruturas de
betão armado. No que diz respeito ao sistema estrutural de lajes fungiformes, os avanços conseguidos
no campo da ciência dos materiais e das técnicas de construção já permitem a construção de estruturas
onde as lajes são reforçadas praticamente apenas por fibras de aço. Para que este novo sistema
construtivo possa competir com os métodos convencionais é necessário que os modelos teóricos que
descrevem o complexo comportamento da ligação laje-pilar acompanhem a evolução destas técnicas
construtivas. No entanto, ainda não existem regras de projeto que considerem a contribuição das fibras
de aço na resistência ao punçoamento de lajes fungiformes.
Com o intuito de contribuir para o aumento do conhecimento sobre o dimensionamento ao
punçoamento centrado de lajes fungiformes de betão reforçado com fibras de aço (BRFA), o presente
artigo apresenta e avalia o desempenho de quatro formulações semi-empíricas. Esse desempenho foi
avaliado comparando-se os resultados previstos por cada modelo, Vteo, com as respostas experimentais,
Vexp, de 154 lajes que compõem a base de dados (BD) construída para este efeito. As lajes da BD, além
de terem rompido todas por punçoamento, também cobrem uma ampla faixa de resistência à
compressão do betão, f
c
, de taxa de armadura de flexão, ρ, de altura útil das lajes, d, de percentagem
volumétrica de fibras, Vf
, e de esbelteza das fibras, L/D, em que L e D são o comprimento e o diâmetro
da fibra. Além da avaliação da relação Vexp/Vteo, também foi avaliada a influência que os parâmetros f
c
,
ρ, Vf
e L/D exercem sobre a capacidade preditiva dos modelos considerados
Armazenamento de sementes de cultivares de Coffea arabica em criopreservação.
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