53 research outputs found
CTX DTM and ORI Mosaics over Sakarya Vallis, Gale Crater, Mars
No full textLocal digital terrain model (DTM) and orthorectified image (ORI) mosaics over Sakarya Vallis, west of Aeolis Mons in Gale crater, Mars. The two constituent DTMs were processed using the CASP-GO suite described in Tao et al. (2018); the ORIs were processed using Ames Stereo Pipeline. The DTMs were then co-registered to an HRSC DTM mosaic (Persaud et al. 2021, https://doi.org/10.5281/zenodo.5808354) and each other using Ames Stereo Pipeline, and then cropped and mosaicked.
Format: GeoTiff
Projection: Equidistant cylindrical
Datum: Spheroid (r = 3396.190 km)
Bit depth: Float32
DTM grid-spacing: 18 m/pixel
ORI resolution: 6 m/pixel
Stereo pairs (from Grindrod and Davis, 2018):
P04_002675_1746_XI_05S222W, B21_017786_1746_XN_05S222W
D02_027834_1748_XN_05S222W, G04_019698_1747_XI_05S222W
Image IDs of the ORIs: P04_002675_1746_XI_05S222W, D02_027834_1748_XN_05S222WThe first author is now at Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California. Contact: [email protected]
30-m HRSC DTM Mosaic of Gale Crater, Mars
No full textDigital terrain model (DTM) mosaic of Gale crater, Mars, processed from High-Resolution Stereo Camera (HRSC) stereo images using the modification of DLR-VICAR described by Kim and Muller (2009).
Format: GeoTiff
Projection: Equidistant cylindrical
Datum: Spheroid (r = 3396.190 km)
Bit depth: Float32
Grid-spacing: 30 m/pixel
Terrain reference: 200-m MOLA and HRSC blended global DTM (Fergason et al. 2018)
HRSC source images: H1938_0000, H1927_0000, and H1916_0000The first author is now at Jet Propulsion Laboratory, California Institute of Technology, Pasadena, California. Contact: [email protected]
On Multi-Resolution 3D Orbital Imagery and Visualisation for Mars Geological Analysis
No full textMars Science Laboratory has revealed a dynamic history of water as the rover has ascended the mysterious Mount Sharp in Gale crater. Because rovers only “see” their local environment, planetary scientists rely on satellite-based orbital imagery to understand the regional geology of Gale crater. However, orbital imagery is map-view—viewed from above, lacking perspective—which presents challenges to interpretation of stratigraphy.
3D visualisation is an emerging opportunity to study orbital images in more intuitive, field-like environments, but has had limited application to Mars. In this work, I formulate and analyse 3D orbital imagery over Gale crater, Mars to investigate the stratigraphy of Mount Sharp 700 m above and 40 km away from MSL. First, I process orbital imagery from the HRSC, CTX, and HiRISE cameras into 3D digital terrain models (DTMs). I then co-register and evaluate these DTMs using statistical tools and existing products to build a new, validated, multi-resolution basemap tied down to MOLA.
Sakarya Vallis, a 400-m deep canyon on Mount Sharp, was then analysed in a 3D environment at 1 m/px. From measurements of exposed rock layers, I construct cross-sections, stratigraphic logs, and a geological unit map to capture this geology. Seven geological units are interpreted across 1 km of exposure, varying in thicknesses (10–174 m) and dips (3–12º). These units may reveal a cyclic depositional environment; a progradational sequence and channel; and unconformities. This work therefore suggests two periods of sub-aqueous deposition in this region during the Late Noachian to Early Hesperian. These results further provide geological context of Gale crater as MSL ascends Mount Sharp, and future inputs for palaeoenvironmental models of Gale crater
CLN3p impacts galactosylceramide transport, raft morphology, and lipid content
No full textJuvenile neuronal ceroid lipofuscinosis (JNCL) belongs to the neuronal ceroid lipofuscinoses characterized by blindness-seizures-motor-cognitive decline and early death. JNCL is caused by CLN3 gene mutations that negatively modulate cell growth-apoptosis. CLN3 protein (CLN3p) localizes to Golgi-Rab4--Rab11-positive endosomes and lipid rafts, and harbors a galactosylceramide (GalCer) lipid raft-binding domain. Goals are proving CLN3p participates in GalCer transport from Golgi to rafts, and GalCer deficits negatively affect cell growth-apoptosis. GalCer-mutant CLN3p are retained in Golgi, with CLN3p rescuing GalCer deficits in rafts. Diminishing GalCer in normal cells by GalCer synthase siRNA negatively affects cell growth-apoptosis. GalCer restores JNCL cell growth. WT CLN3p binds GalCer, but not mutant CLN3p. Sphingolipid content of rafts-Golgi is perturbed with diminished GalCer in rafts and accumulation in Golgi. CLN3-deficient raft vesicular structures are small by transmission electron microscopy, reflecting altered sphingolipid composition of rafts. CLN1-CLN2-CLN6 proteins bind to lysophosphatidic acid-sulfatide, CLN6-CLN8 proteins to GalCer, and CLN8 protein to ceramide. Sphingolipid composition-morphology of CLN1--CLN2--CLN6--CLN8- and CLN9-deficient rafts are altered suggesting changes in raft structure-lipid stoichiometry could be common themes underlying these diseases. Copyright © 2008 International Pediatric Research Foundation, Inc.Boggs JM, 2004, J NEUROSCI RES, V76, P342, DOI 10.1002-jnr.20080; Boustany R.M., 1996, HDB CLIN NEUROLOGY, V22, P671; Brugger B, 2006, P NATL ACAD SCI USA, V103, P2641, DOI 10.1073-pnas.0511136103; Cao Y, 2006, J BIOL CHEM, V281, P20483, DOI 10.1074-jbc.M602180200; de Gassart A, 2003, BLOOD, V102, P4336, DOI 10.1182-blood-2003-03-0871; Dhar S, 2002, ANN NEUROL, V51, P448, DOI 10.1002-ana.10143; Eckford PDW, 2005, BIOCHEM J, V389, P517; Fujita Y, 2000, J NEUROL SCI, V174, P137, DOI 10.1016-S0022-510X(00)00265-3; GAMMON CM, 1987, BIOCHEMISTRY-US, V26, P6239, DOI 10.1021-bi00393a043; Gombos I, 2006, IMMUNOL LETT, V104, P59, DOI 10.1016-j.imlet.2005.11.021; Gottesman MM, 2001, J BIOENERG BIOMEMBR, V33, P453, DOI 10.1023-A:1012866803188; Hanada K, 2003, NATURE, V426, P803, DOI 10.1038-nature02188; Hering H, 2003, J NEUROSCI, V23, P3262; Hirahara Y, 2004, GLIA, V45, P269, DOI 10.1002-glia.10327; Hobert JA, 2007, BIOCHEM BIOPH RES CO, V358, P111, DOI 10.1016-j.bbrc.2007.04.064; Huang Q, 2006, CANCER RES, V66, P5807, DOI 10.1158-0008-5472.CAN-06-0077; JECKEL D, 1992, J CELL BIOL, V117, P259, DOI 10.1083-jcb.117.2.259; Katz ML, 1999, J NEUROSCI RES, V57, P551; Kilkus J, 2003, J NEUROSCI RES, V72, P65, DOI 10.1002-jnr.10549; Kremmidiotis G, 1999, HUM MOL GENET, V8, P523, DOI 10.1093-hmg-8.3.523; LEVINE TP, 2004, TRENDS CELL BIOL, V9, P483; London E, 2000, BBA-BIOMEMBRANES, V1508, P182, DOI 10.1016-S0304-4157(00)00007-1; Luiro K, 2001, HUM MOL GENET, V10, P2123, DOI 10.1093-hmg-10.19.2123; Mahfoud R, 2002, J BIOL CHEM, V277, P11292, DOI 10.1074-jbc.M111679200; Mao QW, 2003, FEBS LETT, V541, P40, DOI 10.1016-S0014-5793(03)00284-9; Margraf LR, 1999, MOL GENET METAB, V66, P283, DOI 10.1006-mgme.1999.2830; Miyaji M, 2005, J EXP MED, V202, P249, DOI 10.1084-jem.20041685; Narayan SB, 2006, ANN NEUROL, V60, P570, DOI 10.1002-ana.20975; Persaud-Sawin DA, 2005, APOPTOSIS, V10, P973, DOI 10.1007-s10495-005-0733-6; Persaud-Sawin DA, 2007, PEDIATR RES, V61, P146, DOI 10.1203-pdr.0b013e31802d8a4a; Persaud-Sawin DA, 2004, PEDIATR RES, V56, P449, DOI 10.1203-01.PDR.0000136152.54638.95; Persaud-Sawin DANW, 2002, HUM MOL GENET, V11, P2129, DOI 10.1093-hmg-11.18.2129; Pullarkat RK, 1997, NEUROPEDIATRICS, V28, P42, DOI 10.1055-s-2007-973665; Rao CS, 2005, BIOPHYS J, V89, P4017, DOI 10.1529-biophysj.105.070631; Rylova SN, 2002, CANCER RES, V62, P801; Sakurai A, 2000, ACTA NEUROPATHOL, V100, P270; Sprong H, 2003, MOL BIOL CELL, V14, P3482, DOI 10.1091-mbc.E03-03-0130; Zaas DW, 2005, BBA-MOL CELL RES, V1746, P305, DOI 10.1016-j.bbamcr.2005.10.00320191
Morpho-Stratigraphy of Sakarya Vallis, Gale Crater, Mars: A Virtual Outcrop Study
No full textSakarya Vallis is a 26-km-long, up to 3.5-km-wide, and up to 450-m-deep feature that cross-cuts the northwest of Mount Sharp in Gale crater, Mars. The center of the canyon is ~30 km from and 700 m higher in elevation than the approximate location of the Mars Science Laboratory (MSL) and exposes the upper Lower mound formation of the Mount Sharp group. Analysis of this immense outcrop can provide insight into the extents and geometries of these rock layers, contribute to understanding of the stratigraphy of Gale crater, and help to inform depositional models of these strata and the formation of Mount Sharp.
We present morpho-stratigraphic interpretations from a 3D HiRISE scene visualized and analyzed as a 400-m-thick, 15-km-long digital outcrop in the 3D visualization environment PRo3D. Seven primary units (packages 1–7) were identified from the exposed stratigraphy based on their visible morphologies, such as bedding styles, key features, sub-packages, and bounding surfaces. Stratigraphic logs and cross-sections were constructed at eleven sites throughout the canyon, derived from topographic profiles and measured layer thicknesses and dips and dip directions (e.g., Fig. 1). Finally, these interpretations were extrapolated over a basemap of the northwest Mt. Sharp, and compared with units identified in other works alongside insight from CRISM.
Four packages exhibit morphologies and bedding geometries that may indicate aqueous deposition or otherwise problematize a layer-cake model for the Lower mound formation: a progradational sequence; cyclic bedding; an unconformity; and a lens feature. The package bounding surfaces overwhelmingly dip to the west and northwest, consistent with other works, while internal layers vary. Initial CRISM analysis reveals monohydrated and polyhydrated sulfates, along with low-Ca pyroxene dust, exposed in Sakarya Vallis, while Package 3 is likely a mix of sulphates and other hydrated mineralogy.
We also present a commentary on both automated and manual image processing techniques and how they affect digital outcrop measurements, with relevance to future 3D studies in this field. It is observed that at changes in slope, slight shifts between the overlying imagery and the terrain data can generate uncertainty in layer boundaries, and this will affect dip/dip-direction measurements
Neuronal ceroid lipofuscinosis: A common pathway?
No full textThe neuronal ceroid lipofuscinoses are pediatric neurodegenerative diseases with common clinical features. Of the nine clinical variants (CLN1-CLN9), six have been genetically identified. Most variants manifest cell death and dysregulated sphingolipid metabolism, suggesting the proteins defective in these disorders may interact along one pathway. NCL patient-derived cell lines exhibit cell growth and apoptotic defects that reverse following transfection with the wild-type gene. The membrane-bound proteins CLN3, CLN6, and CLN8 complement each other, as do CLN1 and CLN2 proteins, with respect to growth and apoptosis. The CLN2 protein also corrects growth and apoptosis in CLN3-, CLN6-, and CLN8-deficient cell lines. Neither CLN1-deficient nor CLN2-deficient growth defects are corrected by CLN3, CLN6, and CLN8 proteins. CLN2, CLN3, CLN6, and CLN8 proteins co-immunoprecipitate and co-localize to early and-or recycling endosomes and lipid rafts. Additionally, CLN2p and CLN1p co-immunoprecipitate. The work presented supports interactions between NCL proteins occurring at multiple points along one pathway. © International Pediatrics Research Foundation, Inc. 2007. All Rights Reserved.BOUSTANY RM, 1993, J INHERIT METAB DIS, V16, P252, DOI 10.1007-BF00710257; BOUSTANY RM, 2006, PEDIAT NEUROLOGY PRI; BOUSTANY RM, 1992, AM J MED GENET, V42, P533, DOI 10.1002-ajmg.1320420421; Boustany R M, 1988, Am J Med Genet Suppl, V5, P47; Bratton SB, 2000, EXP CELL RES, V256, P27, DOI 10.1006-excr.2000.4835; Goebel HH, 1998, BRAIN PATHOL, V8, P151; Goebel HH, 1999, MOL GENET METAB, V66, P367, DOI 10.1006-mgme.1999.2808; Goebel H H, 1996, Semin Pediatr Neurol, V3, P270, DOI 10.1016-S1071-9091(96)80031-3; GOEBEL HH, 1995, J CHILD NEUROL, V10, P424; Granier LA, 2000, EUR J CLIN INVEST, V30, P1011, DOI 10.1046-j.1365-2362.2000.00757.x; Haltia M, 1995, GERONTOLOGY, V41, P239; Hermansson M, 2005, J NEUROCHEM, V95, P609, DOI 10.1111-j.1471-4159.2005.03376.x; Persaud-Sawin DA, 2004, PEDIATR RES, V56, P449, DOI 10.1203-01.PDR.0000136152.54638.95; Persaud-Sawin DANW, 2002, HUM MOL GENET, V11, P2129, DOI 10.1093-hmg-11.18.2129; Rossetti S, 2004, GENOMICS, V84, P1, DOI 10.1016-j.ygeno.2004.02.011; Rylova SN, 2002, CANCER RES, V62, P801; SANTAVUORI P, 1989, ADV EXP MED BIOL, V266, P273; Santavuori P, 2001, Eur J Paediatr Neurol, V5 Suppl A, P157, DOI 10.1053-ejpn.2000.0454; Sleat DE, 1998, BIOCHEM J, V334, P547; TYNNELA J, 1997, NEUROPEDIATRICS, V28, P45; Vesa J, 2002, MOL BIOL CELL, V13, P2410, DOI 10.1091-mbc.E02-01-0031; Weimer JM, 2002, NEUROMOL MED, V1, P111, DOI 10.1385-NMM:1:2:11124252
Space Science in Context: Lessons Learned and Recommendations for IDEA Practice and Beyond
No full textNo abstract available
Teachers' perceptions of the principals' leadership style and the level of implementation of character education programs as related to student academic improvement and discipline, 2002
No full textThis study examined the relationship between the teachers� perceptions of the principals� leadership style in character education and the level of implementation of character education programs as related to student academic improvement and discipline. The following independent variables were: teachers� perceptions of principals� leadership style in character education, level of implementation of character education, student character development, character development in students with discipline problems, character climate, student and teacher demographics. The dependent variables were student academic and student discipline improvement. A quantitative study using a survey instrument was conducted using 25 schools. All school varied according to their socioeconomic status. The 25 schools were not randomly selected but represented the schools approved by local principals to participate in the study. Ninety percent of the third, fourth, and fifth grade teachers in each school responded to a character climate questionnaire. The results of the study indicated a strong interrelated relationship based on a factor analysis among the following variables: student character development, principals� leadership style in character education, level of implementation of character education programs, character climate, character development of students with discipline problems, student academic improvement, and student discipline improvement. The regression analysis revealed a significant positive Beta coefficient (.666) that was significant at the .05 level for the dependent variable student discipline improvement with respect to student academic improvement. Also, the dependent variable, student academic and discipline improvement, had a positive Beta coefficient (.575) that was significant at the .05 level. Student academic improvement and level of implementation of character education programs had a positive Beta coefficient (.208) that was significant at the .05 level. Based on the results, it was recommended that principals support the implementation of the character education program and provide systematic and comprehensive evaluation of the character education program. Grade level chairpersons and the character education committee should provide assistance to teachers with developing innovative strategies and techniques for teaching character education lessons as an integral part of curriculum and instruction
Gender-Based Instruction and the impact on mathematics achievement among males and females grades 3-5, 2009
No full textThe purpose of this study was to examine whether gender-based mathematics classes have a positive impact on the achievement levels of males and females. The study was conducted in order to give insight into the differentiated approach to teaching males and females separately and the effects the separate instruction has on mathematics achievement while closing the achievement gap. This study examined gender-based instruction as a strategy along with other variables that are perceived as having an impact on student achievement. The independent variables in the study were instructional leadership, teacher certification level, teacher content knowledge, teacher knowledge of primary gender learning styles, teacher expectations, gender-based instruction, teacher demographics, and student demographics. The dependent variable was student achievement in mathematics. The study was conducted in an elementary school in Atlanta, Georgia among third, fourth, and filth grade students and teachers. The 2007 Georgia Criterion Reference Competency Test (GCRCT) data were used as pretest data prior to teachers teaching students in a gender-based selling. Eleven teachers were given professional development in male/female primary learning styles. differentiated instruction, culturally responsive teaching, and data analysis. Anonymous surveys were completed by teachers and students. In addition, student demographic data were analyzed. The study was conducted in a Title I elementary school. Ninety-nine percent of the schools students are on free or reduced lunch. The school serves 85% African- American students and 15% Hispanic, Latina/Latino. The schools enrollment, K-5 is approximately 550 students. The results of the study indicated that there was a statistically significant relationship between a teachers content knowledge. years of experience, and his/her expectations relative to student achievement in mathematics. A regression analysis found that the most impacting variables on student achievement in gender-based classrooms were teacher expectancy, teaching experience and instructional leadership. A regression analysis was used to further determine which independent variables had the strongest impact on student achievement in mathematics. The regression showed that the strongest impacting variables again were teacher expectancy, teacher experience and instructional leadership; however, these variables are mediating at best. Those variables found to be the most significant in relationship to student achievement in mathematics were: gender-based instruction, teacher knowledge of student learning styles, and discipline
Correlation of Surface and Subsurface Properties when Choosing a Sampling Site: Applications from Mars and the Moon to Sampling Locations on Europa and Other Ocean Worlds
No full textNo abstract available
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