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Methane emissions inventory verification in southern California
Methane (CH4) and carbon monoxide (CO) mixing ratios were measured at an air quality monitoring station near the Mt. Wilson (MW) Observatory in southern California starting in the spring of 2007. Diurnal variation and mixing ratio correlation (R2 = 0.81) were observed. The correlation results observed agree with previous aircraft measurements collected over the greater Los Angeles (LA) metropolitan area. The consistent agreement between CH4 and CO indicates these gases are well-mixed before reaching the sampling site and the emission source contributions of both compounds are reasonably constant. Since CH4 and CO are considered non-reactive on the time scale of dispersion within the LA urban area and their emission sources are likely to be similarly distributed (e.g., associated with human activities) they are subject to similar scales of atmospheric transport and dilution. This behavior allows the relationship of CH4 and CO to be applied for estimation of CH4 emissions using well-documented CO emissions. Applying this relationship a "top-down" CH4 inventory was calculated for LA County based on the measurements observed at MW and compared with the California Air Resources Board (CARB) "bottom-up" CH4 emissions inventory based on the Intergovernmental Panel on Climate Change recommended methodologies. The "top-down" CH4 emissions inventory is approximately one-third greater than CARB's "bottom-up" inventory for LA County. Considering the uncertainties in both methodologies, the different CH4 emissions inventory approaches are in good agreement, although some under and/or uninventoried CH4 sources may exist
Coefficient of standardized total tract digestibility of phosphorus in oilseed meals and distillers dried grains in growing-finishing pigs
This study was conducted to determine the coefficient of total tract standardized digestibility (CTTSD) of phosphorus (P) in oilseed meals and distillers dried grains (DDG) fed to growing-finishing pigs. Twelve barrows (initial bodyweight (BW) standard deviation, 52.25 +/- 2.57 kg) were allocated individually to metabolism cages. The experimental design was a 12 x 8 incomplete Latin square with 12 dietary treatments and eight replication periods. The diets were formulated individually with dehulled soybean meal produced in Korea (SBM-KD), soybean meal produced in India (SBM-I), soybean meal produced in Korea (SBM-K), corn high-protein distiller dried grains (HPDDGs), tapioca distillers dried grains (TDDG), canola meal (CAM), corn germ meal (CGM), copra meal (CM), palm kernel meal (PKM), sesame meal (SM), perilla meal (PM), and a P-free diet. Intake of P was highest in SM and PM. Excretion of P was reduced in y ascending order as HPDDG, TDDG and CGM; SBM-K; and SM and PM. The CTTAD of P was higher in CGM than SBM-K, TDDG, SM and PM. HPDDG and CGM showed greater CTTSD of P than SBM-K, CAM and PM. Digestible concentration of P on CTTSD (CTTSD-P) of P was greater in PM and CAM than the others except for SBM-KD. In summary, PM could be utilized as an alternative feedstuff to SBM, but its usage is regarded only as a source of P. In addition, the results of the current study would provide valuable information for formulating pig feed with precise P utilization in ingredients using mixed diet
Effects of Rosiglitazone on the Expression of PPAR-γ and the Production of IL-6 and IL-8 in Acute Lung Injury Model Using Human Pulmonary Epithelial Cells
Purpose: Peroxisome proliferator-activated receptor (PPAR)-γ ligand is known to repress the expression of pro-inflammatory mediators. However, it is unclear how it affects PPAR-γ expression and the inflammatory response in the human lung. We investigated the effects of rosiglitazone (synthetic PPAR-γ ligand) on the PPAR-γ expression and on the IL-6 and IL-8 production in acute lung injury model using human lung epithelial cells.Methods: A549 and Beas-2B cells were pre-treated with rosiglitazone and/or BADGE (selective PPAR-γ antagonist) and then treated with media control or cytokine mixture including TNF-α, IL-1 β, and IFN-γ. PPAR-γ expression was analyzed in cell lysates by Western blot. IL-6 and IL-8 production was measured in the culture supernatants by ELISA.Results: PPAR-γ expression was identified in all experimental groups except for the control. The cytokine mixture-induced IL-6 and IL-8 production was significantly inhibited by pre-treatment with rosiglitazone (P<0.01). However, this inhibitory effect of rosiglitazone was not reversed by BADGE.Conclusion: These suggest that rosiglitazone induces the PPAR-γ expression and it may inhibit the cytokine mixture-induced IL-6 and IL-8 production through the PPAR-γ independent pathway. The inhibitory mechanisms of rosiglitazone on the cytokine mixture-induced IL-6 and IL-8 production in human alveolar and bronchial epithelial cells remain to be further investigated.Keywords: Rosiglitazone, PPAR-γ, IL-6, IL-8, Acute lung injur
Effects of Rosiglitazone on the Expression of PPAR-γ and on the Production of IL-6 and IL-8 in Acute Lung Injury Model Using Human Pulmonary Epithelial Cells
Purpose: Peroxisome proliferator-activated receptor (PPAR)-γ ligand is known to repress the expression of pro-inflammatory mediators. However, it is unclear how it affects PPAR-γ expression and the inflammatory response in the human lung. We investigated the effects of rosiglitazone (synthetic PPAR-γ ligand) on the PPAR-γ expression and on the IL-6 and IL-8 production in acute lung injury model using human lung epithelial cells.Methods: A549 and Beas-2B cells were pre-treated with rosiglitazone and/or BADGE (selective PPAR-γ antagonist) and then treated with media control or cytokine mixture including TNF-α, IL-1β, and IFN-γ. PPAR-γ expression was analyzed in cell lysates by Western blot. IL-6 and IL-8 production was measured in the culture supernatants by ELISA.Results: PPAR-γ expression was identified in all experimental groups except for the control. The cytokine mixture-induced IL-6 and IL-8 production was significantly inhibited by pre-treatment with rosiglitazone (P<0.01). However, this inhibitory effect of rosiglitazone was not reversed by BADGE. Conclusion: These suggest that rosiglitazone induces the PPAR-γ expression and it may inhibit the cytokine mixture-induced IL-6 and IL-8 production through the PPAR-γ independent pathway. The inhibitory mechanisms of rosiglitazone on the cytokine mixture-induced IL-6 and IL-8 production in human alveolar, and bronchial epithelial cells remain to be further investigated.Keywords: Rosiglitazone, PPAR-γ expression, IL-6, IL-8, Acute lung injur
Characteristics of biochemical markers and quality parameters using whole wheat flours in Korean wheat cultivars and lines
Characteristics of biochemical markers and quality parameters using whole wheat flours in Korean wheat cultivars and lines
Tese de doutoramento em Ciências e Tecnologias da Informação, apresentada ao Departamento de Engenharia Informática da Faculdade de Ciências e Tecnologia da Universidade de CoimbraO espectro rádio tem vindo a ser regulado de um modo estático. Ou seja, este encontra-se essencialmente dividido em bandas de frequência licenciadas, com utilização restringida a um número limitado de utilizadores autorizados, e em algumas bandas de frequência não licenciadas para utilização livre. Devido à falta de flexibilidade resultante desta abordagem, partes significativas do espectro rádio encontram-se subutilizadas. Em simultâneo, outras bandas de frequência estão a ficar cada vez mais saturadas, nomeadamente as não licenciadas em áreas densamente povoadas.
O Rádio Cognitivo é um paradigma recente cujo objetivo é melhorar o nÃvel de eficiência na utilização do espectro rádio. Os seus princÃpios gerais consistem em permitir que dispositivos sem fios não licenciados (os denominados Utilizadores Secundários) possam aceder à s bandas de frequência licenciadas desde que estes não interferiram de forma prejudicial com os utilizadores licenciados (os denominados Utilizadores Primários). A abordagem preponderante na área de Rádio Cognitivo consiste em ter utilizadores secundários com capacidade para, de um modo dinâmico, detetar e aceder a oportunidades espectrais, ou seja, bandas de frequência que não estão a ser acedidas pelos respetivos utilizadores primários num determinado momento numa determinada localização. Neste contexto, os utilizadores secundários devem ser capazes de analisar o espectro rádio com precisão e, de preferência, possuÃrem mecanismos de aprendizagem baseados em observação local e experiência passada. Apesar da área de Rádio Cognitivo ter implicações na totalidade das camadas das pilhas protocolares de comunicação, os seus problemas fundamentais localizam-se nos nÃveis fÃsico (PHY) e de controlo de acesso ao meio (MAC). Em particular, os protocolos de controlo de acesso ao meio desempenham um papel fundamental no âmbito de operações de controlo de acesso ao espectro rádio e de suporte à cooperação entre utilizadores secundários. Os utilizadores primários, quanto a eles, devem manter-se abstraÃdos das operações de Rádio Cognitivo e, em consequência, não estarem sujeitos a qualquer tipo de alteração em cenários de Rádio Cognitivo.
Esta tese apresenta cinco contribuições, essencialmente relacionadas com o nÃvel do controlo de acesso ao meio, com o objetivo de incrementar os nÃveis de proteção dos utilizadores primários e de desempenho dos utilizadores secundários em redes de Rádio Cognitivo distribuÃdas, especialmente quando os utilizadores secundários não têm antecipadamente acesso a qualquer tipo de informação, tal como a localização de utilizadores primários. Neste tipo de cenário, não existe qualquer entidade central responsável por recolher e processar dados de origem diversa ou tomar decisões de acesso ao espectro rádio. Ou seja, as soluções propostas adequam-se a utilizadores secundários que operam de um modo autónomo e cooperativo. Estes tomam as suas decisões baseando-se, essencialmente, em observações locais, em eventuais resultados de aprendizagem e em dados trocados entre si.
A primeira contribuição desta tese consiste numa descrição da área de Rádio Cognitivo através de um estado da arte detalhado.
A segunda contribuição resulta na definição de um protocolo de controlo de acesso ao meio apoiado num mecanismo inovador, designado COSBET (Cooperative Sense-Before-Transmit), que oferece um nÃvel superior de proteção dos utilizadores primários em cenários de Rádio Cognitivo distribuÃdos sujeitos ao problema do utilizador primário oculto. Este tipo de anomalia ocorre quando um utilizador secundário é incapaz de detetar as atividades de um determinado utilizador primário apesar de poder provocar interferências na respetiva área de abrangência.
Tal como já foi referido, na área de Rádio Cognitivo, é considerado desejável os utilizadores secundários terem capacidades de aprendizagem baseadas em observação local e experiência passada. No entanto, em cenários distribuÃdos, o problema do utilizador primário oculto afeta negativamente a qualidade dos resultados de aprendizagem obtidos e, em consequência, o nÃvel efetivamente alcançado em termos de proteção dos utilizadores primários. Sendo assim, esta tese também analisa esta questão e propõe uma solução destinada a tratá-la, estando esta terceira contribuição baseada num conceito chave designado FIBASC (Filtering Based on Suspicious Channels).
A troca de informação de controlo em redes de Rádio Cognitivo distribuÃdas é frequentemente suportada por um canal partilhado e acessÃvel à globalidade dos utilizadores secundários. Este é o designado canal de controlo comum (CCC), sendo igualmente esta a abordagem seguida pelo protocolo COSBET-MAC proposto. No entanto, os CCC estão sujeitos a problemas de saturação. A ocorrência deste tipo de problema impede os utilizadores secundários de tirarem pleno proveito das potencialidades oferecidas pelo Rádio Cognitivo, acabando por limitar os nÃveis de desempenho de comunicação alcançáveis. Sendo assim, nesta tese também analisamos esta questão e propomos uma solução destinada a abordá-la, correspondendo esta à nossa quarta contribuição. A solução proposta, designada CORHYS (Cognitive Radio Hybrid Signalling), baseia-se num esquema de sinalização hÃbrido que recorre simultaneamente a um CCC e aos canais de dados que vão sendo alocados de forma dinâmica.
A quinta e última contribuição desta tese consiste na definição de uma estratégia adicional, igualmente localizada no nÃvel do controlo de acesso ao meio, destinada a melhorar o desempenho dos utilizadores secundários em cenários de Rádio Cognitivo distribuÃdos em que se recorre a um CCC. Fazem parte das suas linhas orientadoras a otimização da reutilização espacial do espectro rádio e a redução do tráfego de controlo gerado entre utilizadores secundários.
As soluções de Rádio Cognitivo propostas no âmbito desta tese foram avaliadas em ambiente de simulação, sendo esta uma prática comum, nomeadamente devido a limitações de tempo e de outros tipos de recursos. Para o efeito, recorreu-se ao OMNET++ (Objective Modular Network Testbed in C++), um simulador baseado em eventos discretos e de código aberto.
A totalidade das contribuições da presente tese podem ser aplicadas em conjunto. A integração destas deu origem a uma solução única e otimizada de controlo de acesso ao meio destinada a cenários de Rádio Cognitivo distribuÃdos. Esta aborda as duas principais preocupações existentes em cenários de Rádio Cognitivo: proteger os utilizadores primários de qualquer tipo de interferência prejudicial; e melhorar o desempenho de comunicação dos utilizadores secundários. Tanto quanto sabemos, as várias soluções propostas e o nÃvel de completude que a utilização conjunta destas permite não são oferecidos por qualquer outra proposta de controlo de acesso ao meio existente para cenários de Rádio Cognitivo distribuÃdos. As contribuições desta tese também apontam direções que podem ser seguidas no âmbito de outros protocolos de controlo de acesso ao meio, especialmente aqueles que se destinam a redes de Rádio Cognitivo distribuÃdas.The radio spectrum has been statically regulated, i.e., essentially partitioned into licensed
frequency bands, which are accessed exclusively by authorized users, and unlicensed frequency
bands that can be freely accessed. Due to this inflexible policy, large portions of the entire radio
spectrum remain unused independently of time and location in the world, while some frequency
bands suffer from increasing levels of saturation, particularly the unlicensed ones in densely
populated areas. Cognitive Radio (CR) is a recent paradigm that aims at improving efficiency
regarding spectrum utilization. Its principles consist in allowing unlicensed wireless devices (i.e.,
secondary users) to access licensed frequency bands provided that the respective incumbent users
(i.e., primary users) do not suffer any harmful interference. The most preponderant CR approach
consists in having a secondary user (SU) dynamically locating and accessing spectrum
opportunities, i.e., frequency bands that are not being accessed by any primary user (PU) at a
given time and location. Consequently, sensing the spectrum and learning through local
observation and past experience, which enables proactive spectrum decision, are key CR issues.
Despite CR has implications in all the layers of the communication protocol stack, its
fundamentals are mainly related to the physical (PHY) and medium access control (MAC) levels.
In fact, CR MAC protocols are at the heart of spectrum access control and cooperation between
SUs. PUs are expected to be unware of CR operations and, consequently, should not suffer any
modification under CR scenarios.
This thesis provides five contributions, essentially related to the MAC level, with the aim of
improving the protection of PUs and the communication performance of SUs in cooperative
distributed CR networks, particularly when there is no access to any a priori known information,
such as the locations of primary transmitters. In this type of scenario, there are no central entities
that collect and fuse data, or take spectrum decisions. That is, the proposed solutions fit into
totally autonomous and cooperating SUs, i.e., SUs that take their own decisions based on local
observation, on learning outcomes if any is available, and on data they exchange with each other.
The first contribution of this thesis consists in a description of the CR area through an indepth
state of the art.
The second contribution lies in the definition of a CR MAC protocol that follows a novel
approach, named Cooperative Sense-Before-Transmit (COSBET), which provides a higher
protection of PUs in distributed CR scenarios that suffer from the hidden PU problem. This issue
occurs when a SU cannot sense the activities of a given PU despite it can cause harmful
interference to its coverage area. As already mentioned, CR considers that the SUs might have learning capabilities based on
local observation and past experience. However, in distributed scenarios, the hidden PU problem
affects the accuracy of learning and, therefore, the effectiveness of PU protection. For that reason,
in this thesis we also discuss this issue and propose a novel solution that addresses it. This
solution is based on a key concept named FIBASC (Filtering Based on Suspicious Channels).
Utilizing a common control channel (CCC), i.e., a channel that is available to all the SUs in
a CR network, for signalling purposes is a frequent practice concerning existing distributed CR
MAC solutions. It is also the solution adopted by COSBET-MAC. However, a CCC is susceptible
to saturation and can, therefore, become a performance bottleneck that inhibits the SUs from
taking full advantage of CR potentialities. Consequently, the fourth contribution of this thesis
consists in analysing this issue and addressing it through a novel solution, which we named
CORHYS (Cognitive Radio Hybrid Signalling). CORHYS is based on a hybrid signalling
approach that performs signalling over the CCC and over the allocated data channels
simultaneously.
The fifth and last contribution of this thesis consists in a MAC-level strategy that aims at
further improving the performance of SUs in distributed CR scenarios that are based on a CCC.
The key guidelines for this strategy are optimizing the spatial reuse of the radio spectrum and
reducing control traffic.
The CR solutions that resulted from this thesis were evaluated through simulation, which is
a common practice, particularly due to time and other resource restrictions. For this purpose, we
used OMNET++ (Objective Modular Network Testbed in C++), an open source discrete event
simulator.
The contributions of this thesis can be applied jointly and were successfully integrated with
each other, which resulted in an optimized CR MAC solution that addresses the two main
concerns in distributed CR scenarios: protecting the PUs from harmful interference; and
improving the communication performance of the SUs. To the best of our knowledge, the
proposed solutions and the level of completeness that they jointly achieve are not found in any
other existing distributed CR MAC proposal. We also note that they define directions that can be
followed by other CR MAC protocols, particularly those that target distributed CR networks
Effects of propolis on streptococcus mutans, actinomyces naeslundii and staphylococcus aureus
It is known that formation of dental caries is caused by the colonization and accumulation of oral microorganisms and extracellular polysaccharides which are synthesized from sucrose by glucosyltransferases of Streptococcus mutans. Actinomyces naeslundii and Staphylococcus aureus are associated with human root caries and some oral mucosa infections, respectively. In this research Streptococcus mutans Ingbritt 1600 exhibiting glucosyltransferase activity was used to test whether different ethanolic extracts of propolis (EEP) inhibit or not the enzyme activity and growth of the bacteria. Antimicrobial activity of EEP against A. naeslundii and S. aureus was also examined. All EEP from various regions in Brazil inhibited both glucosyltransferase activity and growth of S. mutans, A. naeslundii and S. aureus, but one of propolis from Rio Grande do Sul (RS2) demonstrated highest inhibition of the enzyme activity and growth of the bacteria. It was also found that propolis (RS2) contained highest concentrations of pinocembrin and galangin292014314
SODIUM DODECYL-SULFATE POLYACRYLAMIDE-GEL ELECTROPHORESIS OF PURIFIED CASEIN FRACTIONS TREATED WITH MILK-CLOTTING ENZYMES
65689990
Motion management within two respiratory-gating windows: feasibility study of dual quasi-breath-hold technique in gated medical procedures.
A dual quasi-breath-hold (DQBH) technique is proposed for respiratory motion management (a hybrid technique combining breathing-guidance with breath-hold task in the middle). The aim of this study is to test a hypothesis that the DQBH biofeedback system improves both the capability of motion management and delivery efficiency. Fifteen healthy human subjects were recruited for two respiratory motion measurements (free breathing and DQBH biofeedback breathing for 15 min). In this study, the DQBH biofeedback system utilized the abdominal position obtained using an real-time position management (RPM) system (Varian Medical Systems, Palo Alto, USA) to audio-visually guide a human subject for 4 s breath-hold at EOI and 90% EOE (EOE90%) to improve delivery efficiency. We investigated the residual respiratory motion and the delivery efficiency (duty-cycle) of abdominal displacement within the gating window. The improvement of the abdominal motion reproducibility was evaluated in terms of cycle-to-cycle displacement variability, respiratory period and baseline drift. The DQBH biofeedback system improved the abdominal motion management capability compared to that with free breathing. With a phase based gating (mean ± std: 55  ±  5%), the averaged root mean square error (RMSE) of the abdominal displacement in the dual-gating windows decreased from 2.26 mm of free breathing to 1.16 mm of DQBH biofeedback (p-value = 0.007). The averaged RMSE of abdominal displacement over the entire respiratory cycles reduced from 2.23 mm of free breathing to 1.39 mm of DQBH biofeedback breathing in the dual-gating windows (p-value = 0.028). The averaged baseline drift dropped from 0.9 mm min(-1) with free breathing to 0.09 mm min(-1) with DQBH biofeedback (p-value = 0.048). The averaged duty-cycle with an 1 mm width of displacement bound increased from 15% of free breathing to 26% of DQBH biofeedback (p-value = 0.003). The study demonstrated that the DQBH biofeedback system has the potential to significantly reduce the residual respiratory motion with the improved duty cycle during the respiratory gating procedure
Antipruritic Effect of Acupuncture in Patients with Atopic Dermatitis: Feasibility Study Protocol for a Randomised, Sham-Controlled Trial
© 2017 Yu-Kang Kim et al. This study aims to test the feasibility of a randomised clinical trial to evaluate how acupuncture affects atopic dermatitis (AD) symptoms and quality of life and to explore potential biomarkers that may be associated with AD. It is a sham-controlled trial in which 30 eligible patients will be randomly allocated in a 1: 1: 1 ratio to one of three groups: Verum acupuncture (VA) group 1 (3 times weekly for 4 weeks); VA group 2 (twice weekly for 4 weeks); or sham acupuncture group (SA; twice weekly for 4 weeks). SA will consist of nonpenetrating acupuncture. Outcome measures will include the Visual Analogue Scale for itch, SCORing Atopic Dermatitis, and Eczema Area and Severity Index to evaluate AD symptoms improvement along with the Patient Oriented Eczema Measure and Dermatology Life Quality Index to assess quality of life. Measures will be collected at baseline, once weekly during the treatment period, and after a 4-week follow-up period. Blood collection will be at baseline and 4 and 8 weeks after treatment and compared with healthy controls. Illumina sequencing will be used to profile microRNA expression in each group to explore candidate microRNA biomarkers for specific effects of acupuncture in patients with AD. This trial is registered via US National Institutes of Health Clinical Trials registry (ClinicalTrials.gov) on 15 July 2016, identifier: NCT02844452
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