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Long Term Bathymetry Changes in the Lower Mississippi River due to Variability in Hydrograph and Variable Diversion SchemesReins, Nina J 18 May 2018 (has links)
This research is part of an ongoing effort to improve predictions for bathymetric and morphological changes in the Lower Mississippi River. The utilized model is a subset of a previously calibrated Delft3D model. This shorter model has reduced computational time, and can be deployed for analysis focused on the area between Belle Chasse and HOP, which is the domain of the model. Simulation runs conducted under this study vary from 12 years to 48 years, utilizing a developed 12-year variable hydrograph.
The comparison of variable annual hydrograph and repeated representative annual (uniform) hydrograph input data on bathymetric changes indicated that the absolute bathymetric equilibrium is dependent on year to year variability. The utilization of a uniform hydrograph increases the predicted deposition within the river domain. When evaluating diversion sand capture, utilizing a uniform hydrograph can be considered a conservative approach, while utilizing a variable hydrograph will result in more accurate sand load volumes captured by the diversion.In general, sediment capture showed only minor interdependencies amongst multiple diversions, as long as the total diversion flow is less than 140,000cfs.
This study shows that morphological changes are dependent on the number and location of multiple diversions. The largest interdependencies occur for the most downstream diversions, which increase with the total diverted flow. A true equilibrium was not achieved within 48 years, with or without sea level rise. It was observed, that the system with diversions responds to sea level rise by an increase in deposition, which increases with total diverted flow.
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Additively Manufactured On-Package Multipolar Antenna Systems for Harsh Communication ChannelsRamirez-Hernandez, Ramiro A. 29 June 2018 (has links)
Four main aspects are studied and explored throughout this dissertation: (1) On-Package Multipolar antenna system design for integration with commercial wireless sensor nodes for machine-to-machine communication applications; (2) Development of a novel MMIC packaging process and subsequent antenna integration for chip-to-chip communication applications, (3) Design and characterization of additively manufactured lumped passive elements for integration with MMIC and hybrid circuits, (4) Design and characterization of antennas for on- and off-metal radio frequency identification (RFID) applications.
This work presents the design of different 3-D printed tripolar antenna systems operating at 2.4 GHz. The antennas are designed for integration with commercial wireless nodes with the purpose of mitigating multipath and depolarization channel effects that might be present in many machine-to-machine (M2M) deployments. The antennas are fabricated utilizing an additive manufacturing (AM) approach that combines fused deposition modeling (FDM) of ABS plastic for dielectric parts and micro-dispensing of silver paste Du-Pont CB028 for conductive layers as the majority of the devices presented in this work. Over the air testing demonstrates a 1% channel improvement of up to 14 dB, achieved in a highly-reflective, Rayleigh-like fading environment by implementing selection diversity between three mutually orthogonal monopoles. This improvement leads to better bit error rate (BER) performance (as is also shown). Additionally, RSSI measurements show significant improvement when the prototype antenna system is integrated with commercial wireless sensor hardware. Implications of tripolar antenna integration on M2M systems include reduction in energy use, longer communication link distances, and/or greater link reliability.
In order to incorporate the proposed multipolar selection diversity technique into short range wireless chip-to-chip communications, a novel and versatile 3D printed on-chip integration approach using laser machining is subsequently demonstrated for microwave and mm-wave systems in a process herein referred to as Laser Enhanced or Laser Assisted Direct Print Additive Manufacturing (LE-DPAM). The integration process extends interconnects laterally from a MMIC to a chip carrier. Picosecond laser machining is applied and characterized to enhance the 3D printing quality. Specifically, the width of micro-dispensed printed traces is accurately controlled within micrometer range (e.g. laser cuts ~12 μm wide), additionally, 150 μm probe pads are cut in order to facilitate RF measurement. The S-parameters of a distributed amplifier integrated into the package are simulated and measured from 2 to 30 GHz. It is seen how the overall performance is significantly better than a traditional wirebonded QFN package and previously reported AM MMIC interconnections. The attenuation of the microstrip line including interconnects is only 0.2 dB/mm at 20 GHz and return loss with the package is less than 10 dB throughout the operating frequency band
A 17 GHz package integrated linearly polarized patch antenna, fabricated with a multi-layer and multi-material LE-DPAM process is then introduced for vertical interconnection with a MMIC die. Performance is successfully measured and characterized achieving a return loss greater than 19 dB at the desired design frequency. Good agreement between simulated and measured radiation patterns is also obtained with a peak gain of 4.2 dBi.
Another section of this work utilizes LE-DPAM to fabricate lumped capacitors and inductors for coplanar waveguide (CPW) circuits, especially useful for filtering and matching network implementation. Laser machining is used to achieve ~12 µm slots on printed conductors, producing aspect ratios greater than 2:1, as well as to fabricate vertical interconnects or vias that allow for the fabrication of the multilayer inductors. Inductances in the range of 0.4-3 nH are achieved, with a maximum quality factor of 21, self-resonance frequencies up to 88 GHz, and an inductance per unit of area of 5.3 nH/mm2. Interdigital capacitors in the range of 0.05-0.5 pF are fabricated, having a maximum quality factor of 750 and self-resonances up to 120 GHz. All the components are made on the center line of a CPW that is 836 µm wide. The results show that LE-DPAM enables the fabrication of compact passive circuits that can be easily interconnected with MMIC dies, which at the same time, can be manufactured as part of a larger component. This enables the fabrication of structural electronics that are functional into the mm-wave frequency range.
A final aspect of this work goes through antenna designs for specific RFID (radio frequency identification) applications. RFID tag design is generally focused specifically on either off-metal or on-metal configurations. In this work passive 2D and 3D RFID tags are presented which perform similarly in both configurations. The presented tags operate in the ISM RFID UHF bands that cover 864-868 MHz and 902-928 MHz. A matching loop consisting of two parallel stubs to ground is used for impedance matching to a passive integrated circuit, which has -18 dBm sensitivity. A planar 2D tag with a footprint of 13126.5 mm2 is first introduced, showing a simulated gain of approximately 3 dBi and a measured read range of 10 m (for 31 dBm transmit power from the reader) in both on-metal and off-metal conditions. The tag is miniaturized into a 3D geometry with a footprint of 2524.25 mm2 (520% reduction) and achieves the same broadside simulated on-metal gain. The antennas are fabricated using a DPAM process, and a meshed ground configuration is explored in order to accomplish a 50% conductive paste reduction without disrupting the performance. The proposed tags are compared with commercially available tags as well as previously published tags in terms of read range and size. The tags in this work present an improvement in terms of read range, gain, and area with respect to previous designs covering the ISM RFID UHF bands. Moreover, the performance of these tags is maintained in on- and off-metal conditions, achieving comparable performance and a reduction in volume of 11482% with respect to the best tag reported.
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Characterisation of porosity and root growth in a sodic texture-contrast soilJassogne, Laurence January 2009 (has links)
In Australia a class of soils known as sodic duplex soils covers approximately 20% of the continent. Their defining characteristic is a sharp texture contrast between the A (or E) and B horizon. The upper B horizon at the point of contact with the E horizon is often highly sodic and of such a high strength that root growth and proliferation, water conductivity, aeration, water storage and water uptake are restricted. Roots growing in these soils rely on channels created by previous roots or cracks arising from shrink swell forces associated with seasonal wetting and drying. It has been suggested that by increasing the number of these channels in the subsoil, the structure and permeability of the subsoil would be increased as would be the number of preferential pathways for following generation roots. A biological approach for improving soil macroporosity would be to use plants that can grow through that hostile layer creating new channels. This is known as the primer plant concept. This concept is based on a better understanding of root soil interactions. It is accepted that root growth is influenced by the soil structure and the soil structure is influenced by root growth. However, a lot of these dynamics are still unknown. This project aims to contribute to improving that knowledge by investigating the use of modern techniques to study plant/root interactions in duplex soils. First macroporosity and mesoporosity were characterized in three dimensions using medical computer tomography and micro-tomography. Then the imaging methodology was improved by using a local and adaptive threshold technique based on indicator kriging instead of a global threshold. Using this new methodology, changes in porosity were analysed in intact samples when three different plant species were grown for 12 weeks. The plants were canola (Brassica napus); lucerne (Medicago sativum) and saltbush (Atriplex nummularia) hypothesizing saltbush would change the porosity more because it is a native plant species based on the primer plant concept. The results showed that the porosity changed significantly after root growth but no ii differences were found between plant species. The changes could also not all be attributed to root growth because cracks were also formed after 12 weeks. Therefore, the living roots were visualized and characterized using a new tracing algorithm 'rootviz'. This revealed that saltbush was growing more roots down through the profile. Lucerne seemed to grow roots down the profile as well but to a lesser extend. Both of these plants seemed to have more geotropic features than canola that seemed to grow more laterals and had a more exploratory behaviour.
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Discrimination des fluides à partir de la sismique en réservoir gréseux à huile lourde peu consolidé par des techniques statistiques : applications à la caractérisation de réservoir et au monitoring sismiqueReveron Becerra, Jorge Luis 23 November 2009 (has links) (PDF)
Cette thèse étudie la différenciation des lithologies et fluides à partir de données sismique et de puits dans le réservoir gréseux peu consolidé à huile lourde Morichal (ceinture de l'Orénoque, Venezuela). Dans ces réservoirs, cette discrimination est complexe parce que les lithologies ont des propriétés élastiques similaires et qu'il en est de même pour les sables saturés en eau et ceux saturés en huile lourde (mêmes densités). Dans une première partie, cette problématique de discrimination est analysée au niveau des puits par la détermination d'électrofaciès puis en étudiant la relation entre propriétés pétrophysiques et élastiques. De petites variations de la taille des grains de la roche ou du pourcentage de ciment génèrent des changements de vitesses qui pourraient être utilisés pour discriminer lithologies et fluides. Afin de mieux comprendre pourquoi un premier calage puits-sismique a échoué, une deuxième partie de la thèse a été dédiée à la construction d'un modèle 3D du réservoir, habillé en faciès, propriétés pétrophysiques et élastiques. Ce modèle 3D est ensuite utilisé pour réaliser des tests de modélisations sismiques 1D et 2D, afin d'étudier les effets de l'anisotropie et de l'atténuation sur le signal sismique. En effet, l'anisotropie peut entraîner des changements de phase pour les grands angles d'incidence, et l'atténuation due à la présence d'huile lourde peut causer un retard de phase et un affaiblissement de l'amplitude. Ces deux phénomènes peuvent donc perturber le calage puits-sismique. Après analyse de ces tests, des pistes d'amélioration du calage puits-sismique dans ce contexte géologique sont proposées pour le futur.
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A Multi-Modal Approach for Face Modeling and RecognitionMahoor, Mohammad Hossein 14 January 2008 (has links)
This dissertation describes a new methodology for multi-modal (2-D + 3-D) face modeling and recognition. There are advantages in using each modality for face recognition. For example, the problems of pose variation and illumination condition, which cannot be resolved easily by using the 2-D data, can be handled by using the 3-D data. However, texture, which is provided by 2-D data, is an important cue that cannot be ignored. Therefore, we use both the 2-D and 3-D modalities for face recognition and fuse the results of face recognition by each modality to boost the overall performance of the system. In this dissertation, we consider two different cases for multi-modal face modeling and recognition. In the first case, the 2-D and 3-D data are registered. In this case we develop a unified graph model called Attributed Relational Graph (ARG) for face modeling and recognition. Based on the ARG model, the 2-D and 3-D data are included in a single model. The developed ARG model consists of nodes, edges, and mutual relations. The nodes of the graph correspond to the landmark points that are extracted by an improved Active Shape Model (ASM) technique. In order to extract the facial landmarks robustly, we improve the Active Shape Model technique by using the color information. Then, at each node of the graph, we calculate the response of a set of log-Gabor filters applied to the facial image texture and shape information (depth values); these features are used to model the local structure of the face at each node of the graph. The edges of the graph are defined based on Delaunay triangulation and a set of mutual relations between the sides of the triangles are defined. The mutual relations boost the final performance of the system. The results of face matching using the 2-D and 3-D attributes and the mutual relations are fused at the score level. In the second case, the 2-D and 3-D data are not registered. This lack of registration could be due to different reasons such as time lapse between the data acquisitions. Therefore, the 2-D and 3-D modalities are modeled independently. For the 3-D modality, we developed a fully automated system for 3-D face modeling and recognition based on ridge images. The problem with shape matching approaches such as Iterative Closest Points (ICP) or Hausdorff distance is the computational complexity. We model the face by 3-D binary ridge images and use them for matching. In order to match the ridge points (either using the ICP or the Hausdorff distance), we extract three facial landmark points: namely, the two inner corners of the eyes and the tip of the nose, on the face surface using the Gaussian curvature. These three points are used for initial alignment of the constructed ridge images. As a result of using ridge points, which are just a fraction of the total points on the surface of the face, the computational complexity of the matching is reduced by two orders of magnitude. For the 2-D modality, we model the face using an Attributed Relational Graph. The results of the 2-D and 3-D matching are fused at the score level. There are various techniques to fuse the 2-D and 3-D modalities. In this dissertation, we fuse the matching results at the score level to enhance the overall performance of our face recognition system. We compare the Dempster-Shafer theory of evidence and the weighted sum rule for fusion. We evaluate the performance of the above techniques for multi-modal face recognition on various databases such as Gavab range database, FRGC (Face Recognition Grand Challenge) V2.0, and the University of Miami face database.
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3-D Characterization and Degradation Analysis of Rock aggregatesTolppanen, Pasi January 2001 (has links)
No description available.
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3-D Nautical Charts and Safe NavigationPorathe, Thomas January 2006 (has links)
In spite of all electronic navigation devices on a modern ship bridge, navigators still lose their orientation. Reasons for this might be excessive cognitive workload caused by too many instruments to read and compile, navigation information that is displayed in a cognitively demanding way, short decision times due to high speed or fatigue due to minimum manning and long work hours. This work addresses the problem of map information displayed in a less than optimal way. Three new concepts are presented: the bridge perspective, the NoGO area polygons and a dual lane seaway network. Map reading can be difficult due to the problem of mental rotations. By allowing a 3-D nautical chart to be viewed from an egocentric bridge perspective, the need for mental rotations can be removed. The cognitively demanding calculations necessary to find out if there is enough water under the keel can be made by the chart system and the result displayed as of free water and NoGo areas. On land car driving is facilitated by a road-network and a sign system. This notion can be further developed on sea and make navigation easier and safer. These concepts were then tested in a laboratory experiment, in interviews and in a prototyping project. The results were very promising. The experiment in a laboratory maze showed that map reading from an egocentric perspective was more efficient than using traditional paper and electronic maps. Interviews and expert evaluation of prototypes also showed great interest from practitioners in the field. / Trots all elektronisk utrustning på en modern skeppsbrygga händer det att navigatörerna förlorar orienteringen. Anledningen kan vara hög kognitiv belastning därför att för många olika instrument måste avläsas och integreras samtidigt, att informationen på instrumenten behöver tolkas på ett kognitivt krävande sätt, att tiden för att fatta beslut blir allt kortare på grund av högre hastigheter till sjöss eller på grund av trötthet. I detta arbete presenteras tre nya koncept för visualisering av navigationsinformation: bryggperspektivet, djupvarningspolygoner och sjövägar. Kartläsning kan ibland vara svårt på grund av de mentala rotationer en användare tvingas genomföra för att kunna jämföra kartan med verkligheten. Genom att göra det möjligt för en användare att se sjökortet ur ett egocentriskt bryggperspektiv, så onödiggörs dessa mentala rotationer. De kognitivt krävande beräkningar som navigatören behöver göra för att försäkra sig om att det finns tillräckligt med vatten under kölen, kan utföras av kartsystemet och resultatet visas istället som fria vattenytor och djupvarningsområden (NoGo areas). På land underlättas bilkörning av ett vägnät med körbanor, filer och skyltar. Detta system kan i högre utsträckning införas till sjöss för att underlätta säker navigering. Dessa koncept har sedan testats genom ett laboratorieexperiment, genom intervjuer och i ett prototyputvecklingsprojekt. Resultaten var mycket lovande. Experimentet i en laboratorielabyrint visade klart att 3D-sjökortet var effektivare än både papperskartan och traditionell elektroniska kartor och intervjuerna och expertutvärderingarna visad på stort intresse från yrkesutövare i branschen.
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Regeneration in the adult brain after focal cerebral ischemia : exploration of neurogenesis and angiogenesisJiang, Wei January 2006 (has links)
Background: Ischemic stroke ranks as the third major cause of clinical mortality and the leading cause of handicap in adults. Each year, stroke occurs in about 30,000 Swedes. The severity of an acute ischemic stroke depends mainly on the degree and duration of local cerebral blood flow (lCBF) reduction. Prompt reperfusion improves neurological deficits, spontaneous electrical activity, energy metabolism, cerebral protein synthesis (CPS), and tissue repair, among which cell proliferation (neurogenesis, gliosis) and revascularization (angiogenesis) may have important functional and therapeutic implications. Aims of the thesis: (1) To establish the photothrombotic ring stroke(PRS) model with late spontaneous reperfusion in adult mice; (2) To explore angiogenesis and neurogenesis in adult brain after focal cerebral ischemia. Materials and Methods: The PRS model in C57 BL adult mice and the middle cerebral artery suture occlusion (MCAO) model in adult Wistar rats were used. The 5-bromodeoxyuridine (BrdU) was delivered into animal after stroke induction to label DNA duplication. CBF, CPS and adenosine triphosphate (ATP) were measured by laser-Doppler flowmetry (LDF), [14C]–Iodoantipyrine and [3H]-Leucine double tracer autoradiography, and bioluminescence, respectively. Immunocytochemistry / immunofluoresence were performed to detect different proteins. The cell marker colocalization was analyzed by three-dimension (3-D) confocal. The cell counting was performed with a stereological counting system. Results: The PRS model was established in adult mice by irradiating the exposed skull with a 514.5 nm argon laser ring beam (3 mm diameter, 0.21 mm thick) at an intensity of 0.65 W/cm2 for 60s, with concurrent erythrosin B (4.25 mg/kg) intravenous infusion for 15s. The central cortical region within the ring locus was progressively encroached by an annular ring-shaped perfusion deficit, where lCBF LDF declined promptly to 43% of the baseline value at 30 min post irradiation. The lCBF-IAP amounted to 46-17-58 ml/100g/min, where CPS varied from 57-38-112% at 4h-48h-7days post ischemia. ATP declined at 4h, achieved its maximum level at 48h and was markedly reduced at 7 days postischemia. Morphologically, at 4h some neurons in the region at-risk appeared swollen, at 48h the majority were severely swollen, eosinophilic and pyknotic. Tissue morphology became partly restored at 7 days post stroke, when numerous cortical cells were immunolabeled by BrdU or the mitosis-specific marker phosphorylated histone H3 (Phos-H3). Some of these cells were even doubly immunopositive to the neuron-specific marker Neu N and the astrocyte marker GFAP, as analyzed by 3-D confocal. In adult rats exposed to MCAO, widespread BrdU-immunolabeled cells appeared in the cortex, ipsilateral striatum and dentate gyrus of the hippocampus. Some of which were doubleimmunolabeled by the neuron specific markers Map-2, β-tubulin III and Neu N as analyzed by 3-D confocal. As early as 24h postischemia, BrdU-immunopositive endothelial cells were aligned as microvessels, some of which exhibited distinguishable lumens in the ischemic boundary zone, where VEGF-A, B, C proteins and their receptors flt-1, fik-1, flt-4 were overexpressed at 72h after MCAO. Conclusion: PRS model in adult mice elicits a dynamic deterioration and then restoration of local CBF, CPS, ATP and tissue morphology in the spontaneously reperfused cerebral cortex at 7d after stroke, where cortical neurogenesis and gliosis occurred. In adult rats with MCAO, neurogenesis occurred at 30 and 60d in the penumbral cortex and striatum. Angiogenesis occurred as early as 24h, which contributed to the spontaneous reperfusion frequently observed in this setting of acute ischemic stroke.
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A Bio-Assembly, Mosaic Building, and Informatics System for Cell BiologyBlaylock, April Deirdre January 2007 (has links)
In the field of regenerative medicine, there is a need to develop technologies that can increase the overall efficiency of imaging and expanding cells in culture and in complex heterogeneous arrangements necessary for tissue construction. Long-term live cell imaging has the potential to significantly enhance our understanding of intercellular signaling pathways and the dependence of phenotype on cell arrangement. A transdisciplinary approach has been taken to bridge the fields of cell biology, robotics, and photonics to create a long-term live cell imaging system capable of single cell handling as well as the acquisition of multiple types of data needed for data mining and a general informatics approach to cell culture. A Bio-Assembly Mosaic Builder and Informatics (BAMBI) system was designed and developed using custom software to control a 3-axis stage manufactured by Galil Inc, and custom 1-axis micromanipulator for robotic operations. The software also employs a Sony charged-coupled device sensor for real-time image feedback and data acquisition. The system is mounted on a Carl Zeiss Axiovert 200 inverted microscope. Custom-built environmental controls are used to maintain the temperature, humidity, and gas conditions for extended live cell work. The software was designed using Visual C++ for the Windows PC platform using an object orientated and modular design methodology to allow the BAMBI software to continue to grow with new tasks and demands as needed. The modular approach keeps functional groups of code within context boundaries allowing for easy removal, addition, or changes of functions without compromising the usability of the whole system. BAMBI has been used to image cells within a novel cell culture chamber that constricts cell growth to a true monolayer for high-resolution imaging. In one specific application, BAMBI was also used to characterize and track the development of individual Colony Forming Units (CFU) over the five-day culture period in 5-day CFU-Hill colony assays. The integrated system successfully enabled the tracking and identification of cell types responsible for the formation of the CFU-Hill colonies (a putative endothelial stem cell). BAMBI has been used to isolate single hematopoietic stem cell (HSC) candidate cells, accumulate long-term live cell images, and then return these cells back to the in-vivo environment for further characterization. From these results, further data mining and lineage informatics suggested a novel way to isolate and purify HSCs. Studies such as these are the fundamental next step in developing new therapies for regenerative medicine in the future.
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A Bio-Assembly, Mosaic Building, and Informatics System for Cell BiologyBlaylock, April Deirdre January 2007 (has links)
In the field of regenerative medicine, there is a need to develop technologies that can increase the overall efficiency of imaging and expanding cells in culture and in complex heterogeneous arrangements necessary for tissue construction. Long-term live cell imaging has the potential to significantly enhance our understanding of intercellular signaling pathways and the dependence of phenotype on cell arrangement. A transdisciplinary approach has been taken to bridge the fields of cell biology, robotics, and photonics to create a long-term live cell imaging system capable of single cell handling as well as the acquisition of multiple types of data needed for data mining and a general informatics approach to cell culture. A Bio-Assembly Mosaic Builder and Informatics (BAMBI) system was designed and developed using custom software to control a 3-axis stage manufactured by Galil Inc, and custom 1-axis micromanipulator for robotic operations. The software also employs a Sony charged-coupled device sensor for real-time image feedback and data acquisition. The system is mounted on a Carl Zeiss Axiovert 200 inverted microscope. Custom-built environmental controls are used to maintain the temperature, humidity, and gas conditions for extended live cell work. The software was designed using Visual C++ for the Windows PC platform using an object orientated and modular design methodology to allow the BAMBI software to continue to grow with new tasks and demands as needed. The modular approach keeps functional groups of code within context boundaries allowing for easy removal, addition, or changes of functions without compromising the usability of the whole system. BAMBI has been used to image cells within a novel cell culture chamber that constricts cell growth to a true monolayer for high-resolution imaging. In one specific application, BAMBI was also used to characterize and track the development of individual Colony Forming Units (CFU) over the five-day culture period in 5-day CFU-Hill colony assays. The integrated system successfully enabled the tracking and identification of cell types responsible for the formation of the CFU-Hill colonies (a putative endothelial stem cell). BAMBI has been used to isolate single hematopoietic stem cell (HSC) candidate cells, accumulate long-term live cell images, and then return these cells back to the in-vivo environment for further characterization. From these results, further data mining and lineage informatics suggested a novel way to isolate and purify HSCs. Studies such as these are the fundamental next step in developing new therapies for regenerative medicine in the future.
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