540 research outputs found
Utilization of EREP data in geological evaluation, regional planning, forest management, and water management in North Carolina
The author has identified the following significant results. The S190A, S190B, and S192 photographs and imagery were studied, using standard air-photo interpretation techniques supplemented by color additive viewing and density slicing. The EREP data were found to have potential usefulness for natural resource inventory work, water quality monitoring, and land use mapping for specific problems at scales up to 1:30,000. Distinctions between forest types in North Carolina are limited to conifers, mixed conifer-hardwoods, and hardwoods. Geologic interpretation was limited to detection of lineaments; lithologic differentiation and soil group mapping have proved infeasible in North Carolina except for differentiation of wetland soils in the coastal plain. Imagery from the S192 multispectral scanner has proved to be capable of useful discriminations for vegetation and crop analysis
Urban green space studies with ERTS-1 imagery
There are no author-identified significant results in this report
Utilization of ERTS-1 data in North Carolina
The author has identified the following significant results. ERTS-1 imagery has been used to study forested wetlands, dynamic processes off Coastal North Carolina, and land use patterns in the Wilmington, North Carolina area. The thrust of the investigation is still involvement of state and regional agencies in the use of ERTS-1 imagery in solving some of their day-to-day problems
Size and distance estimation in virtual reality
Abstract. Interest in virtual reality (VR) has been on the rise in the recent few years. However, it is difficult to create virtual environments which provide realistic perception of scale for their users. We wanted to study how humans perceive scale in VR and ways to improve VR scale perception.
We did a pilot test to see how design choices affect distance and height estimation in VR. For pilot tests we had nine test participants.
Based on the experience gathered from the pilot test, we designed the main test. For the main test we had 44 participants. The main test showed similar results for distance estimating as earlier studies. Humans underestimated distances and heights in VR. Having a familiar size object cue, a VR model of a milk carton, next to the object improved height estimations.Koon ja etäisyyden arviointi virtuaalitodellisuudessa. Tiivistelmä. Kiinnostus virtuaalitodellisuuteen (VT) on ollut kasvavaa muutaman viime vuoden aikana. On kuitenkin vaikeaa tehdä virtuaalinen ympäristö, joka luo käyttäjilleen luonnollisen aistimuksen mittakaavasta. Halusimme tutkia, miten ihmiset hahmottavat skaalaa VR:ssä ja kuinka sitä voi parantaa.
Teimme pilottitestejä, jotta näkisimme kuinka erilaiset suunnittelupäätökset vaikuttavat etäisyyden ja korkeuden arviointiin virtuaalitodellisuudessa. Pilottitesteissä oli yhdeksän osallistujaa.
Pilottitestien pohjalta teimme laajemman testin, jossa hyödynsimme pilottitesteistä saatuja kokemuksia. Laajemmassa testissä oli 44 osallistujaa. Tämä testi tuotti samankaltaisia tuloksia etäisyyden arvioinnissa kuin aikaisemmat tutkimukset. Ihmiset aliarvioivat etäisyyksiä ja korkeuksia virtuaalitodellisuudessa. Kun esineen vieressä oli tunnetun kokoinen esine, maitopurkin virtuaalimalli, korkeuden arviointi parani
Exploring Proprotein Convertase Subtilisin/Kexin 9 (PCSK9) Autoproteolysis Process by Molecular Simulations: Hints for Drug Design
Proprotein convertase subtilisin/kexin 9 (PCSK9) is a notable target for the treatment of hypercholesterolemia because it regulates the population of the low-density lipoprotein receptor (LDLR) on liver cells. The PCSK9 zymogen is a serine protease that spontaneously undergoes a double self-cleavage step. The available X-ray structures depict the PCSK9 mature state, but the atomic details of the zymogen state of the enzyme are still unknown. Additionally, why the protease activity of PCSK9 is blocked after the second autoprocessing step remains unclear, as this deviates from other members of the PCSK family. By performing constant-pH molecular dynamics (MD) simulations, we investigated the protonation state of the catalytic triad of PCSK9 and found that it strongly influences the catalytic properties of the enzyme. Moreover, we determined the final step of the maturation process by classical and steered MD simulations. This study could facilitate the identification of ligands capable of interfering with the PCSK9 maturation process
Utilization of ERTS-1 data in geological evaluation, regional planning, forest management, and water management in North Carolina
The author has identified the following significant results. ERTS-1 imagery has been evaluated for use in resource planning and management in North Carolina, and found to be useful for general reconnaissance purposes in forestry, geology, and water resources work. It has also been used for studying large-scale transient phenomena such as river plumes and movement of sediment in the sounds. ERTS-1 imagery has been an aid to geologic and land-use mapping. Stereoscopes, projectors of various kinds, and microscopes have proved useful instruments for the kinds of data acquisition needed by resource planners and managers
First measurements of the number size distribution of 1-2nm aerosol particles released from manufacturing processes in a cleanroom environment
This study was conducted to observe a potential formation and/or release of aerosol particles related to manufacturing processes inside a cleanroom. We introduce a novel technique to monitor airborne sub 2nm particles in the cleanroom and present results from a measurement campaign during which the total particle number concentration (>1nm and >7 nm) and the size resolved concentration in the 1 to 2nm size range were measured. Measurements were carried out in locations where atomic layer deposition (ALD), sputtering, and lithography processes were conducted, with a wide variety of starting materials. During our campaign in the clean room, we observed several time periods when the particle number concentration was 10(5) cm(-3) in the sub 2nm size range and 10(4) cm(-3) in the size class larger than 7nm in one of the sampling locations. The highest concentrations were related to the maintenance processes of the manufacturing machines, which were conducted regularly in that specific location. Our measurements show that around 500cm(-3) sub 2nm particles or clusters were in practice always present in this specific cleanroom, while the concentration of particles larger than 2nm was less than 2cm(-3). During active processes, the concentrations of sub 2nm particles could rise to over 10(5) cm(-3) due to an active new particle formation. The new particle formation was most likely induced by a combination of the supersaturated vapors, released from the machines, and the very low existing condensation sink, leading to pretty high formation rates J(1.4 nm) = (9 4) cm(-3) s(-1) and growth rates of particles (GR(1.1-1.3 nm) = (6 +/- 3) nm/h and GR(1.3-1.8 nm) = (14 +/- 3) nm/h).Copyright (c) 2017 American Association for Aerosol ResearchPeer reviewe
Recent advances in the research of an endemic osteochondropathy in China: Kashin-Beck disease
SummaryKashin-Beck disease (KBD) is an endemic chronic osteochondral disease, which has a high prevalence and morbidity in the Eastern Siberia of Russia, and in the broad diagonal, northern-east to southern-west belt in China and North Korea. In 1990's, it was estimated that in China 1–3 million people had some degree of symptoms of the disease, although even higher estimates have been presented. In China, the extensive prevalence peaked in the late 1950's, but since then, in contrast to the global trend of the osteoarthritis (OA), the number of cases has been dramatically falling. Up to 2013, there are 0.64 millions patients with the KBD and 1.16 millions at risk in 377 counties of 13 provinces or autonomous regions. This is obviously thanks to the preventive efforts carried out, which include providing millions of people with dietary supplements and clean water, as well as relocation of whole villages in China. However, relatively little is known about the molecular mechanisms behind the cartilage damage, the genetic and the environmental risk factors, and the rationale of the preventive effects. During the last decade, new data on a cellular and molecular level has begun to accumulate, which hopefully will uncover the grounds of the disease
Biological Characterization of Computationally Designed Analogs of peptide TVFTSWEEYLDWV (Pep2-8) with Increased PCSK9 Antagonistic Activity
The inhibition of the PCSK9/LDLR protein-protein interaction (PPI) is a promising strategy for developing new hypocholesterolemic agents. Recently, new antibodies have been approved for therapy, but the high cost and low patients\u2019 compliance stimulate the development of alternatives. Starting from the structural information available for the complex between PCSK9 and TVFTSWEEYLDWV (Pep2-8) peptide inhibitor and using computational methods, in this work we identified two Pep2-8 analogs as potential inhibitors of the PCSK9/LDLR PPI. Their biological characterization confirmed the theoretical outcomes. Remarkably, the treatment of HepG2 cells with these peptides increased the LDLR protein level on the cellular membrane, with activities that were 100 and 50 times better than the one of Pep2-8 tested at a 50 \u3bcM concentration. Moreover, they were 50 and 5 times more active than Pep2-8 in improving the functional ability of HepG2 cells to uptake extracellular LDL
Repair of osteochondral defects with recombinant human type II collagen gel and autologous chondrocytes in rabbit
SummaryObjectiveRecombinant human type II collagen (rhCII) gels combined with autologous chondrocytes were tested as a scaffold for cartilage repair in rabbits in vivo.MethodAutologous chondrocytes were harvested, expanded and combined with rhCII-gel and further pre-cultivated for 2 weeks prior to transplantation into a 4 mm diameter lesion created into the rabbit's femoral trochlea (n = 8). Rabbits with similar untreated lesions (n = 7) served as a control group.ResultsSix months after the transplantation the repair tissue in both groups filled the lesion site, but in the rhCII-repair the filling was more complete. Both repair groups also had high proteoglycan and type II collagen contents, except in the fibrous superficial layer. However, the integration to the adjacent cartilage was incomplete. The O'Driscoll grading showed no significant differences between the rhCII-repair and spontaneous repair, both representing lower quality than intact cartilage. In the repair tissues the collagen fibers were abnormally organized and oriented. No dramatic changes were detected in the subchondral bone structure. The repair cartilage was mechanically softer than the intact tissue. Spontaneously repaired tissue showed lower values of equilibrium and dynamic modulus than the rhCII-repair. However, the differences in the mechanical properties between all three groups were insignificant.ConclusionWhen rhCII was used to repair cartilage defects, the repair quality was histologically incomplete, but still the rhCII-repairs showed moderate mechanical characteristics and a slight improvement over those in spontaneous repair. Therefore, further studies using rhCII for cartilage repair with emphasis on improving integration and surface protection are required
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