889 resultados para Enzymatic and non-enzymatic .


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This PhD thesis focused on the analysis and application of microbial membrane lipids as biomarkers in marine sediments. Existing protocols for lipid extraction from marine sediments and biomass were modified. In addition, recent protocols based on high-performance liquid chromatography coupled to mass spectrometry (HPLC-MS) as well as state-of-the-art mass spectrometric analysis by quadrupole time-of-flight (MSqTOF) and the triple quadrupole (MSQQQ) mass spectrometer were used to investigate matrix effects and evaluate the reliability of quantitative analysis in marine environmental samples. The improved lipid extraction and quantification were used to analyze Black Sea water column and sediments samples to a depth of 8 meters from site GeoB 15105 taken during cruise M84/1 (DARCSEAS) with R/V Meteor to apply lipid analysis in benthic bio systems. With this component specific differentiation between planktonic and benthic lipid signature we assessed possible lipid sources. Here, this high detail lipid fingerprinting allowed us to observe changes in the head group and lipid core structures of the intact polar lipids according to the geochemical zonation.

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The Norwegian spring spawning (NSS) herring is an ecologically important fish stock in the Norwegian Sea, and with a catch volume exceeding one million tons a year it is also economically important and a valuable food source. In order to provide a baseline of the levels of contaminants in this fish stock, the levels of organohalogen compounds were determined in 800 individual herring sampled at 29 positions in the Norwegian Sea and off the coast of Norway. Due to seasonal migration, the herring were sampled where they were located during the different seasons. Concentrations of dioxins and dioxin-like PCBs, non-dioxin-like PCBs (PCB7) and PBDEs were determined in fillet samples of individual herring, and found to be relatively low, with means (min-max) of 0.77 (0.24-3.5) ngTEQ/kg wet weight (ww), 5.0 (1.4-24) g/kg ww and 0.47 (0.091-3.1) g/kg ww, respectively. The concentrations varied throughout the year due to the feeding- and spawning cycle: Starved, pre-spawning herring caught off the Norwegian coast in January-February had the highest levels and those caught in the Norwegian Sea in April-June, after further starvation and spawning, had the lowest levels. These results show that the concentrations of organohalogen compounds in NSS herring are relatively low and closely tied to their physiological condition, and that in the future regular monitoring of NSS herring should be made in the spawning areas off the Norwegian coast in late winter.

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Seaweeds are key species of the Baltic Sea benthic ecosystems. They are the substratum of numerous fouling epibionts like bryozoans and tubeworms. Several of these epibionts bear calcified structures and could be impacted by the high pCO2 events of the late summer upwellings in the Baltic nearshores. Those events are expected to increase in strength and duration with global change and ocean acidification. If calcifying epibionts are impacted by transient acidification as driven by upwelling events, their increasing prevalence could cause a shift of the fouling communities toward fleshy species. The aim of the present study was to test the sensitivity of selected seaweed macrofoulers to transient elevation of pCO2 in their natural microenvironment, i.e. the boundary layer covering the thallus surface of brown seaweeds. Fragments of the macroalga Fucus serratus bearing an epibiotic community composed of the calcifiers Spirorbis spirorbis (Annelida) and Electra pilosa (Bryozoa) and the non-calcifier Alcyonidium hirsutum (Bryozoa) were maintained for 30 days under three pCO2 conditions: natural 46059 atm, present-day upwelling1193166 atm and future upwelling 3150446 atm. Only the highest pCO2 caused a significant reduction of growth rates and settlement of S. spirorbis individuals. Additionally, S. spirorbis settled juveniles exhibited enhanced calcification of 40% during daylight hours compared to dark hours, possibly reflecting a day-night alternation of an acidification-modulating effect by algal photosynthesis as opposed to an acidification-enhancing effect of algal respiration. E. pilosa colonies showed significantly increased growth rates at intermediate pCO2 (1193 atm) but no response to higher pCO2. No effect of acidification on A. hirsutum colonies growth rates was observed. The results suggest a remarkable resistance of the algal macro-epibionts to levels of acidification occurring at present day upwellings in the Baltic. Only extreme future upwelling conditions impacted the tubeworm S. spirorbis, but not the bryozoans.

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We compared the responses of native and non-native populations of the seaweed Gracilaria vermiculophylla to heat shock in common garden-type experiments. Specimens from six native populations in East Asia and from eight non-native populations in Europe and on the Mexican Pacific coast were acclimated to two sets of identical conditions before their resistance to heat shock was examined. The experiments were carried out twice - one time in the native range in Qingdao, China and one time in the invaded range in Kiel, Germany - to rule out effects of specific local conditions. In both testing sites the non-native populations survived heat shock significantly better than the native populations, The data underlying this statement are presented in https://doi.pangaea.de/10.1594/PANGAEA.859335. After three hours of heat shock G. vermiculophylla exhibited increased levels of heat shock protein 70 (HSP70) and of a specific isoform of haloperoxidase, suggesting that both enzymes could be required for heat shock stress management. However, the elevated resistance toward heat shock of non-native populations only correlated with an increased constitutive expression of heat shock protein 70 (HSP70). The haloperoxidase isoform was more prominent in native populations, suggesting that not only increased HSP70 expression, but also reduced allocation into haloperoxidase expression after heat shock was selected during the invasion history. The data describing expression of HSP70 and three different isoforms of haloperoxidase are presented in https://doi.pangaea.de/10.1594/PANGAEA.859358.

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In a strategic trade policy, it is assumed, in this paper, that a government changes disbursement or levy method so that the reaction function of home firm approaches infinitely close to that of foreign firm. In the framework of Bertrand-Nash equilibrium, Eaton and Grossman[1986] showed that export tax is preferable to export subsidy. In this paper, it is shown that export subsidy is preferable to export tax in some cases in the framework of Bertrand-Nash equilibrium, considering the uncertainty in demand. Historically, many economists mentioned non-linear subsidy or tax. However, optimum solution of it has not yet been shown. The optimum solution is shown in this paper.

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Since the year 2000 when the Protocol to Prevent, Suppress and Punish Trafficking in Persons, Especially Women and Children, human trafficking has been regarded as one of the egregious violations of human rights, and global efforts have been made to eradicate it. The anti-trafficking framework has multiple dimensions, and the way the anti-trafficking framework is constructed influences its impact on the victims and non-trafficked migrants. This paper will analyze the impact of the anti-trafficking framework on the experiences of Burmese victims and non-trafficked migrants in Thailand. I will question the conventional framework of anti-trafficking, and seek to construct a framework more appropriate for addressing victims' actual needs. In conclusion, the anti-trafficking framework should serve the best interest of the victim; still, it should not be one which might adversely affect the interest of the would-be victim who is not identified as a victim according to the law.

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This paper empirically investigates how far free trade agreements (FTAs) successfully lower tariff rates and non-tariff barriers (NTBs) for manufacturing industries by employing the bilateral tariff and NTB data in a time series for countries around the world. We find that FTAs under GATT Article XXIV and the Enabling Clause contribute to reducing tariff rates by 2.1% points and 1.5% points, respectively. In the case of NTBs, their respective impacts are 6.6% points and 5.7% points. Membership in the World Trade Organization (WTO) does not contribute greatly to reducing tariff rates but does play a significant role in reducing NTBs. These results provide important implications for the literature on numerical assessments of FTAs.

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Based on the consolidated statements data of the universal/commercial banks (UKbank) and non-bank financial institutions with quasi-banking licenses, this paper presents a keen necessity of obtaining data in detail on both sides (assets and liabilities) of their financial conditions and further analyses. Those would bring more adequate assessments on the Philippine financial system, especially with regard to each financial subsector's financing/lending preferences and behavior. The paper also presents a possibility that the skewed locational and operational distribution exists in the non-UKbank financial subsectors. It suggests there may be a significant deviation from the authorities' (the BSP, SEC and others) intended/anticipated financial system in the banking/non-bank financial institutions' real operations.

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Some experiments have been performed to investigate the cyclic freeze-thaw deterioration of concrete, using traditional and non-traditional techniques. Two concrete mixes, with different pore structure, were tested in order to compare the behavior of a freeze-thaw resistant concrete from one that is not. One of the concretes was air entrained, high content of cement and low w/c ratio, and the other one was a lower cement content and higher w/c ratio, without air-entraining agent. Concrete specimens were studied under cyclic freeze-thaw conditions according to UNE-CENT/TS 12390-9 test, using 3% NaCl solution as freezing medium (CDF test: Capillary Suction, De-icing agent and Freeze-thaw Test). The temperature and relative humidity were measured during the cycles inside the specimens using embedded sensors placed at different heights from the surface in contact with the de-icing agent solution. Strain gauges were used to measure the strain variations at the surface of the specimens. Also, measurements of ultrasonic pulse velocity through the concrete specimens were taken before, during, and after the freeze-thaw cycles. According to the CDF test, the failure of the non-air-entraining agent concrete was observed before 28 freeze-thaw cycles; contrariwise, the scaling of the air-entraining agent concrete was only 0.10 kg/m 2 after 28 cycles, versus 3.23 kg/m 2 in the deteriorated concrete, after 28 cycles. Similar behavior was observed on the strain measurements. The residual strain in the deteriorated concrete after 28 cycles was 1150 m versus 65 m, in the air-entraining agent concrete. By means of monitoring the changes of ultrasonic pulse velocity during the freeze-thaw cycles, the deterioration of the tested specimens were assessed

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This paper presents some fundamental properties of independent and-parallelism and extends its applicability by enlarging the class of goals eligible for parallel execution. A simple model of (independent) and-parallel execution is proposed and issues of correctness and efficiency discussed in the light of this model. Two conditions, "strict" and "non-strict" independence, are defined and then proved sufficient to ensure correctness and efciency of parallel execution: if goals which meet these conditions are executed in parallel the solutions obtained are the same as those produced by standard sequential execution. Also, in absence of failure, the parallel proof procedure does not genrate any additional work (with respect to standard SLD-resolution) while the actual execution time is reduced. Finally, in case of failure of any of the goals no slow down will occur. For strict independence the results are shown to hold independently of whether the parallel goals execute in the same environment or in seprate environments. In addition, a formal basis is given for the automatic compile-time generation of independent and-parallelism: compile-time conditions to efficiently check goal independence at run-time are proposed and proved sufficient. Also, rules are given for constructing simpler conditions if information regarding the binding context of the goals to be executed in parallel is available to the compiler.

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Classical imaging optics has been developed over centuries in many areas, such as its paraxial imaging theory and practical design methods like multi-parametric optimization techniques. Although these imaging optical design methods can provide elegant solutions to many traditional optical problems, there are more and more new design problems, like solar concentrator, illumination system, ultra-compact camera, etc., that require maximum energy transfer efficiency, or ultra-compact optical structure. These problems do not have simple solutions from classical imaging design methods, because not only paraxial rays, but also non-paraxial rays should be well considered in the design process. Non-imaging optics is a newly developed optical discipline, which does not aim to form images, but to maximize energy transfer efficiency. One important concept developed from non-imaging optics is the edge-ray principle, which states that the energy flow contained in a bundle of rays will be transferred to the target, if all its edge rays are transferred to the target. Based on that concept, many CPC solar concentrators have been developed with efficiency close to the thermodynamic limit. When more than one bundle of edge-rays needs to be considered in the design, one way to obtain solutions is to use SMS method. SMS stands for Simultaneous Multiple Surface, which means several optical surfaces are constructed simultaneously. The SMS method was developed as a design method in Non-imaging optics during the 90s. The method can be considered as an extension to the Cartesian Oval calculation. In the traditional Cartesian Oval calculation, one optical surface is built to transform an input wave-front to an out-put wave-front. The SMS method however, is dedicated to solve more than 1 wave-fronts transformation problem. In the beginning, only 2 input wave-fronts and 2 output wave-fronts transformation problem was considered in the SMS design process for rotational optical systems or free-form optical systems. Usually SMS 2D method stands for the SMS procedure developed for rotational optical system, and SMS 3D method for the procedure for free-form optical system. Although the SMS method was originally employed in non-imaging optical system designs, it has been found during this thesis that with the improved capability to design more surfaces and control more input and output wave-fronts, the SMS method can also be applied to imaging system designs and possesses great advantage over traditional design methods. In this thesis, one of the main goals to achieve is to further develop the existing SMS-2D method to design with more surfaces and improve the stability of the SMS-2D and SMS-3D algorithms, so that further optimization process can be combined with SMS algorithms. The benefits of SMS plus optimization strategy over traditional optimization strategy will be explained in details for both rotational and free-form imaging optical system designs. Another main goal is to develop novel design concepts and methods suitable for challenging non-imaging applications, e.g. solar concentrator and solar tracker. This thesis comprises 9 chapters and can be grouped into two parts: the first part (chapter 2-5) contains research works in the imaging field, and the second part (chapter 6-8) contains works in the non-imaging field. In the first chapter, an introduction to basic imaging and non-imaging design concepts and theories is given. Chapter 2 presents a basic SMS-2D imaging design procedure using meridian rays. In this chapter, we will set the imaging design problem from the SMS point of view, and try to solve the problem numerically. The stability of this SMS-2D design procedure will also be discussed. The design concepts and procedures developed in this chapter lay the path for further improvement. Chapter 3 presents two improved SMS 3 surfaces design procedures using meridian rays (SMS-3M) and skew rays (SMS-1M2S) respectively. The major improvement has been made to the central segments selections, so that the whole SMS procedures become more stable compared to procedures described in Chapter 2. Since these two algorithms represent two types of phase space sampling, their image forming capabilities are compared in a simple objective design. Chapter 4 deals with an ultra-compact SWIR camera design with the SMS-3M method. The difficulties in this wide band camera design is how to maintain high image quality meanwhile reduce the overall system length. This interesting camera design provides a playground for the classical design method and SMS design methods. We will show designs and optical performance from both classical design method and the SMS design method. Tolerance study is also given as the end of the chapter. Chapter 5 develops a two-stage SMS-3D based optimization strategy for a 2 freeform mirrors imaging system. In the first optimization phase, the SMS-3D method is integrated into the optimization process to construct the two mirrors in an accurate way, drastically reducing the unknown parameters to only few system configuration parameters. In the second optimization phase, previous optimized mirrors are parameterized into Qbfs type polynomials and set up in code V. Code V optimization results demonstrates the effectiveness of this design strategy in this 2-mirror system design. Chapter 6 shows an etendue-squeezing condenser optics, which were prepared for the 2010 IODC illumination contest. This interesting design employs many non-imaging techniques such as the SMS method, etendue-squeezing tessellation, and groove surface design. This device has theoretical efficiency limit as high as 91.9%. Chapter 7 presents a freeform mirror-type solar concentrator with uniform irradiance on the solar cell. Traditional parabolic mirror concentrator has many drawbacks like hot-pot irradiance on the center of the cell, insufficient use of active cell area due to its rotational irradiance pattern and small acceptance angle. In order to conquer these limitations, a novel irradiance homogenization concept is developed, which lead to a free-form mirror design. Simulation results show that the free-form mirror reflector has rectangular irradiance pattern, uniform irradiance distribution and large acceptance angle, which confirm the viability of the design concept. Chapter 8 presents a novel beam-steering array optics design strategy. The goal of the design is to track large angle parallel rays by only moving optical arrays laterally, and convert it to small angle parallel output rays. The design concept is developed as an extended SMS method. Potential applications of this beam-steering device are: skylights to provide steerable natural illumination, building integrated CPV systems, and steerable LED illumination. Conclusion and future lines of work are given in Chapter 9. Resumen La ptica de formacin de imagen clsica se ha ido desarrollando durante siglos, dando lugar tanto a la teora de ptica paraxial y los mtodos de diseo prcticos como a tcnicas de optimizacin multiparamtricas. Aunque estos mtodos de diseo ptico para formacin de imagen puede aportar soluciones elegantes a muchos problemas convencionales, siguen apareciendo nuevos problemas de diseo ptico, concentradores solares, sistemas de iluminacin, cmaras ultracompactas, etc. que requieren mxima transferencia de energa o dimensiones ultracompactas. Este tipo de problemas no se pueden resolver fcilmente con mtodos clsicos de diseo porque durante el proceso de diseo no solamente se deben considerar los rayos paraxiales sino tambin los rayos no paraxiales. La ptica anidlica o no formadora de imagen es una disciplina que ha evolucionado en gran medida recientemente. Su objetivo no es formar imagen, es maximazar la eficiencia de transferencia de energa. Un concepto importante de la ptica anidlica son los rayos marginales, que se pueden utilizar para el diseo de sistemas ya que si todos los rayos marginales llegan a nuestra rea del receptor, todos los rayos interiores tambin llegarn al receptor. Haciendo uso de este principio, se han diseado muchos concentradores solares que funcionan cerca del lmite terico que marca la termodinmica. Cuando consideramos ms de un haz de rayos marginales en nuestro diseo, una posible solucin es usar el mtodo SMS (Simultaneous Multiple Surface), el cul disea simultneamente varias superficies pticas. El SMS naci como un mtodo de diseo para ptica anidlica durante los aos 90. El mtodo puede ser considerado como una extensin del clculo del valo cartesiano. En el mtodo del valo cartesiano convencional, se calcula una superficie para transformar un frente de onda entrante a otro frente de onda saliente. El mtodo SMS permite transformar varios frentes de onda de entrada en frentes de onda de salida. Inicialmente, slo era posible transformar dos frentes de onda con dos superficies con simetra de rotacin y sin simetra de rotacin, pero esta limitacin ha sido superada recientemente. Nos referimos a SMS 2D como el mtodo orientado a construir superficies con simetra de rotacin y llamamos SMS 3D al mtodo para construir superficies sin simetra de rotacin o free-form. Aunque el mtodo originalmente fue aplicado en el diseo de sistemas anidlicos, se ha observado que gracias a su capacidad para disear ms superficies y controlar ms frentes de onda de entrada y de salida, el SMS tambin es posible aplicarlo a sistemas de formacin de imagen proporcionando una gran ventaja sobre los mtodos de diseo tradicionales. Uno de los principales objetivos de la presente tesis es extender el mtodo SMS-2D para permitir el diseo de sistemas con mayor nmero de superficies y mejorar la estabilidad de los algoritmos del SMS-2D y SMS-3D, haciendo posible combinar la optimizacin con los algoritmos. Los beneficios de combinar SMS y optimizacin comparado con el proceso de optimizacin tradicional se explican en detalle para sistemas con simetra de rotacin y sin simetra de rotacin. Otro objetivo importante de la tesis es el desarrollo de nuevos conceptos de diseo y nuevos mtodos en el rea de la concentracin solar fotovoltaica. La tesis est estructurada en 9 captulos que estn agrupados en dos partes: la primera de ellas (captulos 2-5) se centra en la ptica formadora de imagen mientras que en la segunda parte (captulos 6-8) se presenta el trabajo del rea de la ptica anidlica. El primer captulo consta de una breve introduccin de los conceptos bsicos de la ptica anidlica y la ptica en formacin de imagen. El captulo 2 describe un proceso de diseo SMS-2D sencillo basado en los rayos meridianos. En este captulo se presenta el problema de disear un sistema formador de imagen desde el punto de vista del SMS y se intenta obtener una solucin de manera numrica. La estabilidad de este proceso se analiza con detalle. Los conceptos de diseo y los algoritmos desarrollados en este captulo sientan la base sobre la cual se realizarn mejoras. El captulo 3 presenta dos procedimientos para el diseo de un sistema con 3 superficies SMS, el primero basado en rayos meridianos (SMS-3M) y el segundo basado en rayos oblicuos (SMS-1M2S). La mejora ms destacable recae en la seleccin de los segmentos centrales, que hacen ms estable todo el proceso de diseo comparado con el presentado en el captulo 2. Estos dos algoritmos representan dos tipos de muestreo del espacio de fases, su capacidad para formar imagen se compara diseando un objetivo simple con cada uno de ellos. En el captulo 4 se presenta un diseo ultra-compacto de una cmara SWIR diseada usando el mtodo SMS-3M. La dificultad del diseo de esta cmara de espectro ancho radica en mantener una alta calidad de imagen y al mismo tiempo reducir drsticamente sus dimensiones. Esta cmara es muy interesante para comparar el mtodo de diseo clsico y el mtodo de SMS. En este captulo se presentan ambos diseos y se analizan sus caractersticas pticas. En el captulo 5 se describe la estrategia de optimizacin basada en el mtodo SMS-3D. El mtodo SMS-3D calcula las superficies pticas de manera precisa, dejando slo unos pocos parmetros libres para decidir la configuracin del sistema. Modificando el valor de estos parmetros se genera cada vez mediante SMS-3D un sistema completo diferente. La optimizacin se lleva a cabo variando los mencionados parmetros y analizando el sistema generado. Los resultados muestran que esta estrategia de diseo es muy eficaz y eficiente para un sistema formado por dos espejos. En el captulo 6 se describe un sistema de compresin de la Etendue, que fue presentado en el concurso de iluminacin del IODC en 2010. Este interesante diseo hace uso de tcnicas propias de la ptica anidlica, como el mtodo SMS, el teselado de las lentes y el diseo mediante grooves. Este dispositivo tiene un lmite terica en la eficiencia del 91.9%. El captulo 7 presenta un concentrador solar basado en un espejo free-form con irradiancia uniforme sobre la clula. Los concentradores parablicos tienen numerosas desventajas como los puntos calientes en la zona central de la clula, uso no eficiente del rea de la clula al ser sta cuadrada y adems tienen ngulos de aceptancia de reducido. Para poder superar estas limitaciones se propone un novedoso concepto de homogeneizacin de la irrandancia que se materializa en un diseo con espejo free-form. El anlisis mediante simulacin demuestra que la irradiancia es homognea en una regin rectangular y con mayor ngulo de aceptancia, lo que confirma la viabilidad del concepto de diseo. En el captulo 8 se presenta un novedoso concepto para el diseo de sistemas afocales dinmicos. El objetivo del diseo es realizar un sistema cuyo haz de rayos de entrada pueda llegar con ngulos entre 45 mientras que el haz de rayos a la salida sea siempre perpendicular al sistema, variando nicamente la posicin de los elementos pticos lateralmente. Las aplicaciones potenciales de este dispositivo son varias: tragaluces que proporcionan iluminacin natural, sistemas de concentracin fotovoltaica integrados en los edificios o iluminacin direccionable con LEDs. Finalmente, el ltimo captulo contiene las conclusiones y las lneas de investigacin futura.