The Mars 2020
Perseverance
rover is equipped with a next-generation engineering camera imaging system that represents an upgrade over previous Mars rover missions. These upgrades will improve the ...operational capabilities of the rover with an emphasis on drive planning, robotic arm operation, instrument operations, sample caching activities, and documentation of key events during entry, descent, and landing (EDL). There are a total of 16 cameras in the
Perseverance
engineering imaging system, including 9 cameras for surface operations and 7 cameras for EDL documentation. There are 3 types of cameras designed for surface operations: Navigation cameras (Navcams, quantity 2), Hazard Avoidance Cameras (Hazcams, quantity 6), and Cachecam (quantity 1). The Navcams will acquire color stereo images of the surface with a
96
∘
×
73
∘
field of view at 0.33 mrad/pixel. The Hazcams will acquire color stereo images of the surface with a
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×
102
∘
at 0.46 mrad/pixel. The Cachecam, a new camera type, will acquire images of Martian material inside the sample tubes during caching operations at a spatial scale of 12.5 microns/pixel. There are 5 types of EDL documentation cameras: The Parachute Uplook Cameras (PUCs, quantity 3), the Descent stage Downlook Camera (DDC, quantity 1), the Rover Uplook Camera (RUC, quantity 1), the Rover Descent Camera (RDC, quantity 1), and the Lander Vision System (LVS) Camera (LCAM, quantity 1). The PUCs are mounted on the parachute support structure and will acquire video of the parachute deployment event as part of a system to characterize parachute performance. The DDC is attached to the descent stage and pointed downward, it will characterize vehicle dynamics by capturing video of the rover as it descends from the skycrane. The rover-mounted RUC, attached to the rover and looking upward, will capture similar video of the skycrane from the vantage point of the rover and will also acquire video of the descent stage flyaway event. The RDC, attached to the rover and looking downward, will document plume dynamics by imaging the Martian surface before, during, and after rover touchdown. The LCAM, mounted to the bottom of the rover chassis and pointed downward, will acquire
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×
90
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FOV images during the parachute descent phase of EDL as input to an onboard map localization by the Lander Vision System (LVS). The rover also carries a microphone, mounted externally on the rover chassis, to capture acoustic signatures during and after EDL. The
Perseverance
rover launched from Earth on July 30th, 2020, and touchdown on Mars is scheduled for February 18th, 2021.
Aims
To develop and evaluate the performance of a panel of isothermal real‐time recombinase polymerase amplification (RPA) assays for detection of common bacterial urinary tract infection (UTI) ...pathogens.
Methods and Results
The panel included RPAs for Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis, Pseudomonas aeruginosa and Enterococcus faecalis. All five RPAs required reaction times of under 12 min to reach their lower limit of detection of 100 genomes per reaction or less, and did not cross‐react with high concentrations of nontarget bacterial genomic DNA. In a 50‐sample retrospective clinical study, the five‐RPA assay panel was found to have a specificity of 100% (95% CI, 78–100%) and a sensitivity of 89% (95% CI, 75–96%) for UTI detection.
Conclusions
The analytical and clinical validity of RPA for the rapid and sensitive detection of common UTI pathogens was established.
Significance and Impact of the Study
Rapid identification of the causative pathogens of UTIs can be valuable in preventing serious complications by helping avoid the empirical treatment necessitated by traditional urine culture's 48–72‐h turnaround time. The routine and widespread use of RPA to supplement or replace culture‐based methods could profoundly impact UTI management and the emergence of multidrug‐resistant pathogens.
Participation in physical activity and sports is known to have positive implications for physical health, and for social and emotional wellbeing of children. Following corrective spinal surgery for ...scoliosis, the timeline for the return to activities and sports varies from surgeon to surgeon and from location to location, and return to activities can be limited due to pain, fear, and decreased flexibility. It is critical that patients know best-practice guidelines, and it is equally critical that medical professionals know whether their patients are following those guidelines. This paper includes a summary of recommendations published in the literature, and a pilot study to address a gap in the literature on determining how long, post-surgery, adolescents with idiopathic scoliosis waited before returning to various self-care and physical activities, and what factors influenced return to activities. We used a mixed-method approach that involved two phases: a questionnaire (n = 8), and subsequent interviews of some participants (n = 3). Participants were ages 14-17 (M = 15.4) and had had posterior instrumentation and fusion for scoliosis in the past 2 years.
Some patients were cautious about return to activities, either because of emotional or medical reasons. However, in many instances, participants returned to physical activities earlier than was recommended, primarily for emotional and social reasons.
We define the radiative forcings used in climate simulations with the SI2000 version of the Goddard Institute for Space Studies (GISS) global climate model. These include temporal variations of ...well‐mixed greenhouse gases, stratospheric aerosols, solar irradiance, ozone, stratospheric water vapor, and tropospheric aerosols. Our illustrations focus on the period 1951–2050, but we make the full data sets available for those forcings for which we have earlier data. We illustrate the global response to these forcings for the SI2000 model with specified sea surface temperature and with a simple Q‐flux ocean, thus helping to characterize the efficacy of each forcing. The model yields good agreement with observed global temperature change and heat storage in the ocean. This agreement does not yield an improved assessment of climate sensitivity or a confirmation of the net climate forcing because of possible compensations with opposite changes of these quantities. Nevertheless, the results imply that observed global temperature change during the past 50 years is primarily a response to radiative forcings. It is also inferred that the planet is now out of radiation balance by 0.5 to 1 W/m2 and that additional global warming of about 0.5°C is already “in the pipeline.”
•BSE-SEM assessed for measurement of mineral content in caries and erosive lesions•Caries lesions - good correlation (R2 = 0.98) with mineral loss data from TMR•Erosive lesions - good correlation ...(R2 = 0.99) with Vickers micro-hardness•BSE-SEM analysis is rapid and low-cost method for mineral content in enamel lesions
To assess Scanning Electron Microscopy in Back-Scattered Emission mode (BSE-SEM) for measurement of lesion mineral content as a function of depth. Direct comparison is made with Transverse Micro-Radiography (TMR) and Surface Micro-Hardness (SMH) on carious and erosive lesions.
Caries lesions prepared from sound bovine enamel at 37 °C and pH 4.6 in unsaturated (7d) or part-saturated (8d, 4.1 mM Ca2+, 8 mM Pi) lactic acid /methyl cellulose gel system, followed by TMR analysis. Erosive lesions prepared from sound bovine enamel (1% citric acid, pH3.8, room temperature) for 5, 10, 15 or 20 min at n = 10 per treatment group. SMH readings (Vickers diamond, 1.9 N, 20 s) were taken from acid-treated and reference areas of each sample. BSE-SEM performed on polished cross-sections of lesioned samples (Jeol JSM6490LV SEM; high vacuum, 10 keV beam voltage, magnification x500 with constant working distance of 10 mm). Under identical SEM conditions, polished standards i.e. MgF2, alumina, Mg, Al and Si provided a calibration plot of BSE-SEM signal vs. atomic number (z¯). Mineral content vs. depth plots were derived from the cross-sectional BSE-SEM data.
Cross-sectional BSE-SEM images clearly differentiate between caries and erosive lesions. Comparison of caries lesion mineral loss from BSE-SEM with TMR data showed good correlation (R2 = 0.98). Similarly, comparison of BSE-SEM data from erosive lesions showed good correlation (R2 = 0.99) with hardness loss data from SMH.
BSE-SEM provides a relatively rapid and cost-effective method for the assessment of mineral content in demineralised tooth enamel and is applicable to both caries and erosive lesions.
A series of satellite total solar irradiance (TSI) observations can be combined in a precise solar magnetic cycle length composite TSI database by determining the relationship between two ...non‐overlapping components: ACRIM1 and ACRIM2. Willson and Hudson, 1991; Willson, 1994 An ACRIM composite TSI time series using the Nimbus7/ERB results Hoyt et al., 1992 to relate ACRIM1 and ACRIM2 demonstrates a secular upward trend of 0.05 percent‐per‐decade between consecutive solar activity minima. Willson, 1997 A PMOD TSI composite using ERBS Lee et al., 1995 comparisons to relate ACRIM1 and ACRIM2 Fröhlich and Lean, 1998 differs from the ACRIM composite in two significant respects: a negligible trend between solar minima and lower TSI at solar maxima. Our findings indicate the lower PMOD trend and lower PMOD TSI at the maxima of solar cycles 22 and 23 are artifacts of ERBS degradation. Lower PMOD TSI during the maximum of cycle 21 results from modifications of Nimbus7/ERB and ACRIM1 published results that produces better agreement with a TSI/solar proxy model Foukal and Lean, 1988; Lean et al., 1995; Fröhlich and Lean, 1998.
Needs of parents with children with scoliosis are complex and depend on their child’s treatments. The purpose of this study was to identify needs of parents with children with scoliosis. This ...qualitative description involved interviews with parents of children at various stages of treatment. A convenience, then purposeful sample of 16 parents (12 mothers, two fathers, and two stepfathers) was interviewed; interviews were transcribed and analyzed using thematic analysis. Parents’ needs included: Needing reliable medical information; Desiring information on complementary treatments; Wanting help in supporting and advocating for their child; Needing to protect the child and family; and Seeking connection and support. Although many parents’ needs are being met, this study recommends a nursing role aimed at providing parents with reliable medical information, discussing alternative treatments, assisting parents in their role of supporting their child, helping parents in their advocacy efforts, and referring parents to appropriate connections.
Communicative rationality offers a new paradigm for transportation planning. Drawing on the literature and lessons from transportation planning practice, this paper describes the characteristics of a ...“communicative” form of transportation planning and compares them with conventional practices. A communicative rationality paradigm would place language and discourse at the core of transportation planning. The paper argues that it would lead to greater attention to desired transportation ends (goals), better integration of means and ends, new forms of participation and learning, and enhanced deliberative capacity. The paper explains the implications of this paradigm for the role of the transportation planner, the purpose of planning, the planning process, communicative practices, problem framing, and the nature of planning analysis. The paper concludes with an assessment of communicative rationality's ability to promote more effective transportation planning. It seeks to create a dialogue that will support the investigation of new transportation planning processes. Copyright Kluwer Academic Publishers 2001
Mars Exploration Rover Engineering Cameras Maki, J. N.; Bell III, J. F.; Herkenhoff, K. E. ...
Journal of Geophysical Research - Planets,
December 2003, Letnik:
108, Številka:
E12
Journal Article
Recenzirano
Odprti dostop
NASA's Mars Exploration Rover (MER) Mission will place a total of 20 cameras (10 per rover) onto the surface of Mars in early 2004. Fourteen of the 20 cameras are designated as engineering cameras ...and will support the operation of the vehicles on the Martian surface. Images returned from the engineering cameras will also be of significant importance to the scientific community for investigative studies of rock and soil morphology. The Navigation cameras (Navcams, two per rover) are a mast‐mounted stereo pair each with a 45° square field of view (FOV) and an angular resolution of 0.82 milliradians per pixel (mrad/pixel). The Hazard Avoidance cameras (Hazcams, four per rover) are a body‐mounted, front‐ and rear‐facing set of stereo pairs, each with a 124° square FOV and an angular resolution of 2.1 mrad/pixel. The Descent camera (one per rover), mounted to the lander, has a 45° square FOV and will return images with spatial resolutions of ∼4 m/pixel. All of the engineering cameras utilize broadband visible filters and 1024 × 1024 pixel detectors.
Descent image motion estimation system is the first machine-vision system for estimating lander velocity during planetary descent. Composed of sensors and software, DIMES features a descent imager, a ...radar altimeter, an inertial-measurement unit, and an algorithm for combining sensor measurements to estimate horizontal velocity - the speed across the planet's surface the lander travels as it descends. Although the sensors are not novel technology, the algorithm and flight software that combines them are new. This algorithm combines radar, image, and inertial data in a novel way to create a low-cost, robust, and computationally efficient solution to the horizontal-velocity-estimation problem. This article describes the DIMES algorithm, its testing, and its performance during both Mars exploration rover landings.
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