909 resultados para high-turbidity coastal environments


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Coastal flooding poses serious threats to coastal areas around the world, billions of dollars in damage to property and infrastructure, and threatens the lives of millions of people. Therefore, disaster management and risk assessment aims at detecting vulnerability and capacities in order to reduce coastal flood disaster risk. In particular, non-specialized researchers, emergency management personnel, and land use planners require an accurate, inexpensive method to determine and map risk associated with storm surge events and long-term sea level rise associated with climate change. This study contributes to the spatially evaluation and mapping of social-economic-environmental vulnerability and risk at sub-national scale through the development of appropriate tools and methods successfully embedded in a Web-GIS Decision Support System. A new set of raster-based models were studied and developed in order to be easily implemented in the Web-GIS framework with the purpose to quickly assess and map flood hazards characteristics, damage and vulnerability in a Multi-criteria approach. The Web-GIS DSS is developed recurring to open source software and programming language and its main peculiarity is to be available and usable by coastal managers and land use planners without requiring high scientific background in hydraulic engineering. The effectiveness of the system in the coastal risk assessment is evaluated trough its application to a real case study.

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Since historical times, coastal areas throughout the eastern Mediterranean are exposed to tsunami hazard. For many decades the knowledge about palaeotsunamis was solely based on historical accounts. However, results from timeline analyses reveal different characteristics affecting the quality of the dataset (i.e. distribution of data, temporal thinning backward of events, local periodization phenomena) that emphasize the fragmentary character of the historical data. As an increasing number of geo-scientific studies give convincing examples of well dated tsunami signatures not reported in catalogues, the non-existing record is a major problem to palaeotsunami research. While the compilation of historical data allows a first approach in the identification of areas vulnerable to tsunamis, it must not be regarded as reliable for hazard assessment. Considering the increasing economic significance of coastal regions (e.g. for mass tourism) and the constantly growing coastal population, our knowledge on the local, regional and supraregional tsunami hazard along Mediterranean coasts has to be improved. For setting up a reliable tsunami risk assessment and developing risk mitigation strategies, it is of major importance (i) to identify areas under risk and (ii) to estimate the intensity and frequency of potential events. This approach is most promising when based on the analysis of palaeotsunami research seeking to detect areas of high palaeotsunami hazard, to calculate recurrence intervals and to document palaeotsunami destructiveness in terms of wave run-up, inundation and long-term coastal change. Within the past few years, geo-scientific studies on palaeotsunami events provided convincing evidence that throughout the Mediterranean ancient harbours were subject to strong tsunami-related disturbance or destruction. Constructed to protect ships from storm and wave activity, harbours provide especially sheltered and quiescent environments and thus turned out to be valuable geo-archives for tsunamigenic high-energy impacts on coastal areas. Directly exposed to the Hellenic Trench and extensive local fault systems, coastal areas in the Ionian Sea and the Gulf of Corinth hold a considerably high risk for tsunami events, respectively.Geo-scientific and geoarcheaological studies carried out in the environs of the ancient harbours of Krane (Cefalonia Island), Lechaion (Corinth, Gulf of Corinth) and Kyllini (western Peloponnese) comprised on-shore and near-shore vibracoring and subsequent sedimentological, geochemical and microfossil analyses of the recovered sediments. Geophysical methods like electrical resistivity tomography and ground penetrating radar were applied in order to detect subsurface structures and to verify stratigraphical patterns derived from vibracores over long distances. The overall geochronological framework of each study area is based on radiocarbon dating of biogenic material and age determination of diagnostic ceramic fragments. Results presented within this study provide distinct evidence of multiple palaeotsunami landfalls for the investigated areas. Tsunami signatures encountered in the environs of Krane, Lechaion and Kyllini include (i) coarse-grained allochthonous marine sediments intersecting silt-dominated quiescent harbour deposits and/or shallow marine environments, (ii) disturbed microfaunal assemblages and/or (iii) distinct geochemical fingerprints as well as (iv) geo-archaeological destruction layers and (v) extensive units of beachrock-type calcarenitic tsunamites. For Krane, geochronological data yielded termini ad or post quem (maximum ages) for tsunami event generations dated to 4150 ± 60 cal BC, ~ 3200 ± 110 cal BC, ~ 650 ± 110 cal BC, and ~ 930 ± 40 cal AD, respectively. Results for Lechaion suggest that the harbour was hit by strong tsunami impacts in the 8th-6th century BC, the 1st-2nd century AD and in the 6th century AD. At Kyllini, the harbour site was affected by tsunami impact in between the late 7th and early 4th cent. BC and between the 4th and 6th cent. AD. In case of Lechaion and Kyllini, the final destruction of the harbour facilities also seems to be related to the tsunami impact. Comparing the tsunami signals obtained for each study areas with geo-scientific data from palaeotsunami events from other sites indicates that the investigated harbour sites represent excellent geo-archives for supra-regional mega-tsunamis.

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The growing need to assess the environmental status of the Mediterranean coastal marine habitats and the large availability of data collected by Reef Check Italia onlus (RCI) volunteers suggest the possibility to develop innovative and reliable indices that may support decision makers in applying conservation strategies. The aims of this study were to check the reliability of data collected by RCI volunteers, analyse the spatial and temporal distribution of RCI available data, resume the knowledge on the biology and ecology of the monitored species, and develop innovative indices to asses the ecological quality of Mediterranean subtidal rocky shores and coralligenous habitats. Subtidal rocky shores and coralligenous were chosen because these are the habitats more attractive for divers; therefore mlst data are referring to them, moreover subtidal rocky bottom are strongly affected by coastal urbanisation, land use, fishing and tourist activities, that increase pollution, turbidity and sedimentation. Non-indigenous species (NIS) have been recognized as a major threat to the integrity of Mediterranean native communities because of their proliferation, spread and impact on resident communities. Monitoring of NIS’ spreading dynamics at the basin spatial scale is difficult but urgent. According to a field test, the training provided by RCI appears adequate to obtain reliable data by volunteers. Based on data collected by RCI volunteers, three main categories of indices were developed: indices based on species diversity, indices on the occurrence non-indigenous species, and indices on species sensitive toward physical, chemical and biological disturbances. As case studies, indices were applied to stretches of coastline defined according to management criteria (province territories and marine protected areas). The assessments of ecological quality in the Tavolara Marine Protected Area using the species sensitivities index were consisten with those previously obtained with traditional methods.

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Polychaetes are one of the larger groups of macroinvertebrates with more than 9000 species recognised, distributed worldwide. Thanks to the broad ecological adaptability and high abundaces, this taxon plays a leading role and is considered an important component of all benthic assemblages. Our knowledge about the West Iberian Coast polychaete fauna are scarce, and the only studies are recent. In this sense, the aim of this work was to investigate the composition and the spatial distribution of the polychaete fauna along the NW Portuguese Coastal Shelf, focusing on their relationship to environmental factors (depth, grain size, longitude and latitude) and to add new data to the existing biological dataset. A total of 39 sites were analysed, collected in an area of about 5665 km², between 20 and 150 m depth, distributed in a way to cover the overall grain size gradient. A total of 9352 specimens belonging to 41 families were found, and the analysis based on the abundance of polychaete species revealed five affinity groups: (a) nearshore medium sand characterised by Pisione parapari and Hesionura elongata; (b) very coarse sand that showed the highest abundance of Syllidae and was characterised by Protodorvillea kefersteini and Syllis garciai; (c) fine sand dominated by Spiophanes bombyx and Glycera tridactyla; (d) very fine sand with Nepthys assimilis and Amage sp. and the highest abundance of Paraonidae; (d) mud characterised by Labioleanira yhleni and Ampharete finmarchica. The combination of the environmental variables and the biological data, done with BIOENV routine, demonstrated that depth, grain size and fine contents were the best related with the biological data (rho=0.598). In general, the results agree with the composition and the spatial distribution of the polychaete fauna in other parts of the world; further polychaete assemblages related to mud sediments were firstly recorded in the Northwestern Portuguese Coastal Shelf.

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Site-selective spectroscopy in hexagonal beta-NaYF4:Er3+,Yb3+ has revealed different environments for Er3+ ions (multisite formation). The low-temperature S-4(3/2) -> (I15/2Er3+)-I-4 green emission depends on the excitation wavelength associated with the F-4(7/2) Er3+ level. We have studied the effect of hydrostatic pressure on the green, red, and blue Er3+ emission upon NIR excitation at similar to 980 nm, in order to establish the role played by energy resonance conditions and the multiple Er3+ sites due to the disordered structure for the upconversion (UC) process (energy tuning). The variation of photoluminescence spectra and lifetimes as a function of pressure and temperature reveals that the origin of the high green UC efficiency of the beta-NaYF4:Er3+,Yb3+ compound is mainly due to the multisite distribution, and the low phonon energy of the host lattice.

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Dispersal and recruitment are central processes that shape the geographic and temporal distributions of populations of marine organisms. However, significant variability in factors such as reproductive output, larval transport, survival, and settlement success can alter the genetic identity of recruits from year to year. We designed a temporal and spatial sampling protocol to test for genetic heterogeneity among adults and recruits from multiple time points along a similar to 400 km stretch of the Oregon (USA) coastline. In total, 2824 adult and recruiting Balanus glandula were sampled between 2001 and 2008 from 9 sites spanning the Oregon coast. Consistent with previous studies, we observed high mitochondrial DNA diversity at the cytochrome oxidase I locus (884 unique haplotypes) and little to no spatial genetic population structure among the 9 sites (Phi(ST) = 0.00026, p = 0.170). However, subtle but significant temporal shifts in genetic composition were observed among year classes (Phi(ST) = 0.00071, p = 0.035), and spatial Phi(ST) varied from year to year. These temporal shifts in genetic structure were correlated with yearly differences in the strength of coastal upwelling (p = 0.002), with greater population structure observed in years with weaker upwelling. Higher levels of barnacle settlement were also observed in years with weaker upwelling (p < 0.001). These data suggest the hypothesis that low upwelling intensity maintains more local larvae close to shore, thereby shaping the genetic structure and settlement rate of recruitment year classes.

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HIV-1 negative factor (Nef) elevates virus replication and contributes to immune evasion in vivo. As one of its established in vitro activities, Nef interferes with T-lymphocyte chemotaxis by reducing host cell actin dynamics. To explore Nef's influence on in vivo recirculation of T lymphocytes, we assessed lymph-node homing of Nef-expressing primary murine lymphocytes and found a drastic impairment in homing to peripheral lymph nodes. Intravital imaging and 3D immunofluorescence reconstruction of lymph nodes revealed that Nef potently impaired T-lymphocyte extravasation through high endothelial venules and reduced subsequent parenchymal motility. Ex vivo analyses of transendothelial migration revealed that Nef disrupted T-lymphocyte polarization and interfered with diapedesis and migration in the narrow subendothelial space. Consistently, Nef specifically affected T-lymphocyte motility modes used in dense environments that pose high physical barriers to migration. Mechanistically, inhibition of lymph node homing, subendothelial migration and cell polarization, but not diapedesis, depended on Nef's ability to inhibit host cell actin remodeling. Nef-mediated interference with in vivo recirculation of T lymphocytes may compromise T-cell help and thus represents an important mechanism for its function as a HIV pathogenicity factor.

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Paleogene sedimentary rocks of the Arkose Ridge Formation (Talkeetna Mountains, Alaska) preserve a record of a fluvial-lacustrine depositional environment and its forested ecosystem in an active basin among the convergent margin tectonic processes that shaped southern Alaska. An -800 m measured succession at Box Canyon indicates braid-plain deposition with predominantly gravelly deposits low in the exposure to sandy and muddy facies associations below an overlying lava flow sequence. U-Pb geochronology on zircons from a tuff and a sandstone within the measured section, as well as an Ar/Ar date from the overlying lava constrain the age of the sedimentary succession to between similar to 59 Ma and 48 Ma Fossil plant remains occur throughout the Arkose Ridge Formation as poorly-preserved coalified woody debris and fragmentary leaf impressions. At Box Canyon, however, a thin la-custrine depositional lens of rhythmically laminated mudrocks yielded fish fossils and a well-preserved floral assemblage including foliage and reproductive organs representing conifers, sphenopsids, monocots, and dicots. Leaf physiognomic methods to estimate paleoclimate were applied to the dicot leaf collection and indicate warm temperate paleotemperatures (-11-15 +/- -4 degrees C MAT) and elevated paleoprecipitation (-120 cm/yr MAP) estimates as compared to modem conditions; results that are parallel with previously published estimates from the partly coeval Chickaloon Formation deposited in more distal depositional environments in the same basin. The low abundance of leaf herbivory in the Box Canyon dicot assemblage (-9% of leaves damaged) is also similar to the results from assemblages in the meander-plain depositional systems of the Chickaloon. This new suite of data informs models of the tectonostratigraphic evolution of southern Alaska and the developing understanding of terrestrial paleoecology and paleoclimate at high latitudes during the Late Paleocene-Early Eocene greenhouse climate phase. (c) 2014 Elsevier B.V. All rights reserved.

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It is a globally important challenge to meet increasing demands for resources and, at the same time, protect biodiversity and ecosystem services. Farming is usually regarded as a major threat to biodiversity due to its expansion into natural areas. We compared biodiversity of bees and wasps between heterogeneous small-scale farming areas and protected forest in northern coastal Belize, Central America. Malaise traps operated for three months during the transition from wet to dry season. Farming areas consisted of a mosaic of mixed crop types, open habitat, secondary forest, and agroforestry. Mean species richness per site (alpha diversity), as well as spatial and temporal community variation (beta diversity) of bees and wasps were equal or higher in farming areas compared to protected forest. The higher species richness and community variation in farmland was due to additional species that did not occur in the forest, whereas most species trapped in forest were also found in farming areas. The overall regional species richness (gamma diversity) increased by 70% with the inclusion of farming areas. Our results suggest that small-scale farming systems adjacent to protected forest may not only conserve, but even favour, biodiversity of some taxonomic groups. We can, however, not exclude possible declines of bee and wasp diversity in more intensified farmland or in landscapes completely covered by heterogeneous farming systems.

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Acute thrombotic arterial occlusion is the leading cause of morbidity and mortality in the Western world. Von Willebrand factor is thought to be the only indispensable adhesive substrate to promote thrombus formation in high shear environments. We found that thrombospondin-1, a glycoprotein enriched in arteriosclerotic plaques, might function as an alternative substrate for thrombus formation. Platelets adhered to thrombospondin-1 in a shear dependent manner with an optimum shear as found in stenosed arteries. Adhesion is extremely firm, with no detachment of platelets up to a shear rate of 4000 s(-1). Experiments using platelets from a patient completely lacking von Willebrand factor showed that von Willebrand factor is not involved in platelet binding to thrombospondin-1. Platelet adhesion to thrombospondin-1 is not mediated via beta3-integrins or GPIa. CD36 partially mediates the adhesion of pre-activated platelets. We identified GPIb as high shear adhesion-receptor for thrombospondin-1. Soluble GPIb, as well as antibodies against the GPIb, blocked platelet adhesion almost completely. The new discovered thrombospondin-1-GPIb adhesion axis under arterial shear conditions might be important, not only during thrombus formation but also for pathological processes where other cells bind to the endothelium or subendothelium, including arteriosclerosis, inflammation and tumor metastasis, and a promising therapeutic target.

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This chapter reviews the history of study and the current status of Mid-Holocene climatic and cultural change in the South Central Andes, which host a wide range of different habitats from Pacific coastal areas up to extremely harsh cold and dry environments of the high mountain plateau, the altiplano or the puna. Paleoenvironmental information reveals high amplitude and rapid changes in effective moisture during the Holocene period and, consequently, dramatically changing environmental conditions. Therefore, this area is suitable to study the response of hunting and gathering societies to environmental changes, because the smallest variations in the climatic conditions have large impacts on resources and the living space of humans. This chapter analyzes environmental and paleoclimatic information from lake sediments, ice cores, pollen profiles, and geomorphic processes and relates these with the cultural and geographic settlement patterns of human occupation in the different habitats in the area of southern Peru, southwest Bolivia, northwest Argentina, and north Chile and puts in perspective of the early and late Holocene to present a representative range of environmental and cultural changes. It has been found that the largest changes took place around 9000 cal yr BP when the humid early Holocene conditions were replaced by extremely arid but highly variable climatic conditions. These resulted in a marked decrease of human occupation, “ecological refuges,” increased mobility, and an orientation toward habitats with relatively stable resources (such as the coast, the puna seca, and “ecological refuges”).

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This dissertation investigates high performance cooperative localization in wireless environments based on multi-node time-of-arrival (TOA) and direction-of-arrival (DOA) estimations in line-of-sight (LOS) and non-LOS (NLOS) scenarios. Here, two categories of nodes are assumed: base nodes (BNs) and target nodes (TNs). BNs are equipped with antenna arrays and capable of estimating TOA (range) and DOA (angle). TNs are equipped with Omni-directional antennas and communicate with BNs to allow BNs to localize TNs; thus, the proposed localization is maintained by BNs and TNs cooperation. First, a LOS localization method is proposed, which is based on semi-distributed multi-node TOA-DOA fusion. The proposed technique is applicable to mobile ad-hoc networks (MANETs). We assume LOS is available between BNs and TNs. One BN is selected as the reference BN, and other nodes are localized in the coordinates of the reference BN. Each BN can localize TNs located in its coverage area independently. In addition, a TN might be localized by multiple BNs. High performance localization is attainable via multi-node TOA-DOA fusion. The complexity of the semi-distributed multi-node TOA-DOA fusion is low because the total computational load is distributed across all BNs. To evaluate the localization accuracy of the proposed method, we compare the proposed method with global positioning system (GPS) aided TOA (DOA) fusion, which are applicable to MANETs. The comparison criterion is the localization circular error probability (CEP). The results confirm that the proposed method is suitable for moderate scale MANETs, while GPS-aided TOA fusion is suitable for large scale MANETs. Usually, TOA and DOA of TNs are periodically estimated by BNs. Thus, Kalman filter (KF) is integrated with multi-node TOA-DOA fusion to further improve its performance. The integration of KF and multi-node TOA-DOA fusion is compared with extended-KF (EKF) when it is applied to multiple TOA-DOA estimations made by multiple BNs. The comparison depicts that it is stable (no divergence takes place) and its accuracy is slightly lower than that of the EKF, if the EKF converges. However, the EKF may diverge while the integration of KF and multi-node TOA-DOA fusion does not; thus, the reliability of the proposed method is higher. In addition, the computational complexity of the integration of KF and multi-node TOA-DOA fusion is much lower than that of EKF. In wireless environments, LOS might be obstructed. This degrades the localization reliability. Antenna arrays installed at each BN is incorporated to allow each BN to identify NLOS scenarios independently. Here, a single BN measures the phase difference across two antenna elements using a synchronized bi-receiver system, and maps it into wireless channel’s K-factor. The larger K is, the more likely the channel would be a LOS one. Next, the K-factor is incorporated to identify NLOS scenarios. The performance of this system is characterized in terms of probability of LOS and NLOS identification. The latency of the method is small. Finally, a multi-node NLOS identification and localization method is proposed to improve localization reliability. In this case, multiple BNs engage in the process of NLOS identification, shared reflectors determination and localization, and NLOS TN localization. In NLOS scenarios, when there are three or more shared reflectors, those reflectors are localized via DOA fusion, and then a TN is localized via TOA fusion based on the localization of shared reflectors.

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Experimental warming provides a method to determine how an ecosystem will respond to increased temperatures. Northern peatland ecosystems, sensitive to changing climates, provide an excellent setting for experimental warming. Storing great quantities of carbon, northern peatlands play a critical role in regulating global temperatures. Two of the most common methods of experimental warming include open top chambers (OTCs) and infrared (IR) lamps. These warming systems have been used in many ecosystems throughout the world, yet their efficacy to create a warmer environment is variable and has not been widely studied. To date, there has not been a direct, experimentally controlled comparison of OTCs and IR lamps. As a result, a factorial study was implemented to compare the warming efficacy of OTCs and IR lamps and to examine the resulting carbon dioxide (CO2) and methane (CH4) flux rates in a Lake Superior peatland. IR lamps warmed the ecosystem on average by 1-2 #°C, with the majority of warming occurring during nighttime hours. OTC's did not provide any long-term warming above control plots, which is contrary to similar OTC studies at high latitudes. By investigating diurnal heating patterns and micrometeorological variables, we were able to conclude that OTCs were not achieving strong daytime heating peaks and were often cooler than control plots during nighttime hours. Temperate day-length, cloudy and humid conditions, and latent heat loss were factors that inhibited OTC warming. There were no changes in CO2 flux between warming treatments in lawn plots. Gross ecosystem production was significantly greater in IR lamp-hummock plots, while ecosystem respiration was not affected. CH4 flux was not significantly affected by warming treatment. Minimal daytime heating differences, high ambient temperatures, decay resistant substrate, as well as other factors suppressed significant gas flux responses from warming treatments.

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Prediction of radiated fields from transmission lines has not previously been studied from a panoptical power system perspective. The application of BPL technologies to overhead transmission lines would benefit greatly from an ability to simulate real power system environments, not limited to the transmission lines themselves. Presently circuitbased transmission line models used by EMTP-type programs utilize Carson’s formula for a waveguide parallel to an interface. This formula is not valid for calculations at high frequencies, considering effects of earth return currents. This thesis explains the challenges of developing such improved models, explores an approach to combining circuit-based and electromagnetics modeling to predict radiated fields from transmission lines, exposes inadequacies of simulation tools, and suggests methods of extending the validity of transmission line models into very high frequency ranges. Electromagnetics programs are commonly used to study radiated fields from transmission lines. However, an approach is proposed here which is also able to incorporate the components of a power system through the combined use of EMTP-type models. Carson’s formulas address the series impedance of electrical conductors above and parallel to the earth. These equations have been analyzed to show their inherent assumptions and what the implications are. Additionally, the lack of validity into higher frequencies has been demonstrated, showing the need to replace Carson’s formulas for these types of studies. This body of work leads to several conclusions about the relatively new study of BPL. Foremost, there is a gap in modeling capabilities which has been bridged through integration of circuit-based and electromagnetics modeling, allowing more realistic prediction of BPL performance and radiated fields. The proposed approach is limited in its scope of validity due to the formulas used by EMTP-type software. To extend the range of validity, a new set of equations must be identified and implemented in the approach. Several potential methods of implementation have been explored. Though an appropriate set of equations has not yet been identified, further research in this area will benefit from a clear depiction of the next important steps and how they can be accomplished. Prediction of radiated fields from transmission lines has not previously been studied from a panoptical power system perspective. The application of BPL technologies to overhead transmission lines would benefit greatly from an ability to simulate real power system environments, not limited to the transmission lines themselves. Presently circuitbased transmission line models used by EMTP-type programs utilize Carson’s formula for a waveguide parallel to an interface. This formula is not valid for calculations at high frequencies, considering effects of earth return currents. This thesis explains the challenges of developing such improved models, explores an approach to combining circuit-based and electromagnetics modeling to predict radiated fields from transmission lines, exposes inadequacies of simulation tools, and suggests methods of extending the validity of transmission line models into very high frequency ranges. Electromagnetics programs are commonly used to study radiated fields from transmission lines. However, an approach is proposed here which is also able to incorporate the components of a power system through the combined use of EMTP-type models. Carson’s formulas address the series impedance of electrical conductors above and parallel to the earth. These equations have been analyzed to show their inherent assumptions and what the implications are. Additionally, the lack of validity into higher frequencies has been demonstrated, showing the need to replace Carson’s formulas for these types of studies. This body of work leads to several conclusions about the relatively new study of BPL. Foremost, there is a gap in modeling capabilities which has been bridged through integration of circuit-based and electromagnetics modeling, allowing more realistic prediction of BPL performance and radiated fields. The proposed approach is limited in its scope of validity due to the formulas used by EMTP-type software. To extend the range of validity, a new set of equations must be identified and implemented in the approach. Several potential methods of implementation have been explored. Though an appropriate set of equations has not yet been identified, further research in this area will benefit from a clear depiction of the next important steps and how they can be accomplished.

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This dissertation presents a detailed study in exploring quantum correlations of lights in macroscopic environments. We have explored quantum correlations of single photons, weak coherent states, and polarization-correlated/polarization-entangled photons in macroscopic environments. These included macroscopic mirrors, macroscopic photon number, spatially separated observers, noisy photons source and propagation medium with loss or disturbances. We proposed a measurement scheme for observing quantum correlations and entanglement in the spatial properties of two macroscopic mirrors using single photons spatial compass state. We explored the phase space distribution features of spatial compass states, such as chessboard pattern by using the Wigner function. The displacement and tilt correlations of the two mirrors were manifested through the propensities of the compass states. This technique can be used to extract Einstein-Podolsky-Rosen correlations (EPR) of the two mirrors. We then formulated the discrete-like property of the propensity Pb(m,n), which can be used to explore environmental perturbed quantum jumps of the EPR correlations in phase space. With single photons spatial compass state, the variances in position and momentum are much smaller than standard quantum limit when using a Gaussian TEM00 beam. We observed intrinsic quantum correlations of weak coherent states between two parties through balanced homodyne detection. Our scheme can be used as a supplement to decoy-state BB84 protocol and differential phase-shift QKD protocol. We prepared four types of bipartite correlations ±cos2(θ12) that shared between two parties. We also demonstrated bits correlations between two parties separated by 10 km optical fiber. The bits information will be protected by the large quantum phase fluctuation of weak coherent states, adding another physical layer of security to these protocols for quantum key distribution. Using 10 m of highly nonlinear fiber (HNLF) at 77 K, we observed coincidence to accidental-coincidence ratio of 130±5 for correlated photon-pair and Two-Photon Interference visibility >98% entangled photon-pair. We also verified the non-local behavior of polarization-entangled photon pair by violating Clauser-Horne-Shimony-Holt Bell’s inequality by more than 12 standard deviations. With the HNLF at 300 K (77 K), photon-pair production rate about factor 3(2) higher than a 300 m dispersion-shifted fiber is observed. Then, we studied quantum correlation and interference of photon-pairs; with one photon of the photon-air experiencing multiple scattering in a random medium. We observed that depolarization noise photon in multiple scattering degrading the purity of photon-pair, and the existence of Raman noise photon in a photon-pair source will contribute to the depolarization affect. We found that quantum correlation of polarization-entangled photon-pair is better preserved than polarization-correlated photon-pair as one photon of the photon-pair scattered through a random medium. Our findings showed that high purity polarization-entangled photon-pair is better candidate for long distance quantum key distribution.