2,149 research outputs found
Letter from Mrs. L. T. W. Conger to John Muir, 1902 Feb 11.
[4]hear of some heartbreaking grief with its terrible desolation has crossed my pathway the old thought has come back, Look it in the eye, and I have thus been enabled to live through much sorrow that if I had yielded to my first feelings would have swept me out into the dark ocean of despair. If you should ever come this way be sure to call and see us. Thanking you for your kind remembrance I am as everYour Sincere Friend(Mrs) L. T. W. Conger.[1]344 North Raymond Avenue.Pasadena Feb. 11, 1902.Mr John Muir:My Dear Friend.You can scarcely imagine through the kindness of Mr [Kendal?], your gift of California Mountains. Every description of tree, flower, and animal, brings back my childhood\u27s home, with endearing memories,02594 [2]for I lived among the mountains and pines of dear old Maine. I often recall a little experiance of those days. When about eight years old I started for school one morning without my brother and sisters, and on reaching a piece of heavy timber a large black bear walked out of the woods and deliberately seated himself a few feet in front of me and looked into my face.[3]For a moment I was almost paralized with fear; but soon recalled an oft repeated remark of my fathers, that if you looked a bear calmly in the eye without mo[illegible]ing he would not harm you. This I did; and to my great relief in a few moments he quietly crossed to the other side of the road and was soon out of sight. This to me has been a life long lesson. Whenever the blac
The Intersection of Privacy and Security
There is a common misconception that privacy and security are the same thing. The reality is that while there is an intersection of these two topics, there are differences between security and privacy. This paper sets up through illustrations some similarities and differences between these topics
Socioeconomic risk, parenting during the preschool years and child health age 6 years
Parent–child relationships and parenting processes are emerging as potential life course
determinants of health. Parenting is socially patterned and could be one of the factors responsible for
the negative effects of social inequalities on health, both in childhood and adulthood. This study tests
the hypothesis that some of the effect of socioeconomic risk on health in mid childhood is transmitted
via early parenting. Methods: Prospective cohort study in 10 USA communities involving 1041 mother/
child pairs, selected at birth at random with conditional sampling. Exposures: income, maternal
education, maternal age, lone parenthood, ethnic status and objective assessments of mother child
interaction in the first 4 years of life covering warmth, negativity and positive control. Outcomes:
mother’s report of child’s health in general at 6 years. Modelling: multiple regression analyses with
statistical testing of mediational processes. Results: All five indicators of socioeconomic status (SES) were
correlated with all three measures of parenting, such that low SES was associated with poor parenting.
Among the measures of parenting maternal warmth was independently predictive of future health, and
among the socioeconomic variables maternal education, partner presence and ‘other ethnic group’
proved predictive. Measures of parenting significantly mediated the impact of measures of SES on child
health. Conclusions: Parenting mediates some, but not all of the detectable effects of socioeconomic
risk on health in childhood. As part of a package of measures that address other determinants,
interventions to support parenting are likely to make a useful contribution to reducing childhood
inequalities in health
Nonlinear System Level Synthesis for Polynomial Dynamical Systems
This work introduces a controller synthesis method via system level synthesis
for nonlinear systems characterized by polynomial dynamics. The resulting
framework yields finite impulse response, time-invariant, closed-loop transfer
functions with guaranteed disturbance cancellation. Our method generalizes
feedback linearization to enable partial feedback linearization, where the
cancellation of the nonlinearity is spread across a finite-time horizon. This
provides flexibility to use the system dynamics to attenuate disturbances
before cancellation via control, reducing the cost of control compared with
feedback linearization while maintaining guarantees about disturbance
rejection. This approach is illustrated on a benchmark example and on a common
model for fluid flow control.Comment: accepted to CDC 202
GEOSAT Follow-On (GFO) Altimeter Document Series, Volume 8: GFO Altimeter Engineering Assessment Report Update:The First 109 Cycles Since Acceptance November 29, 2000 to December 26, 2005
The purpose of this document is to present and document GFO performance analyses and results. This is the fifth Assessment Report since the initial report. This report extends the performance assessment since acceptance to 26 December 2005. The initial GFO Altimeter Engineering Assessment Report, March 2001 (NASA/TM-2001-209984/Ver.1/Vol.1) covered the GFO performance from Launch to Acceptance (10 February 1998 to 29 November 2000). The second of the series covered the performance from Acceptance to the end of Cycle 20 (29 November 2000 to 21 November 2001). The third of the series covered the performance from Acceptance to the end of Cycle 42 (29 November 2000 to 30 November 2002). The fourth of the series covered the performance from Acceptance to the end of Cycle 64 (29 November 2000 to 17 December 2003). The fifth of the series covered performance from Acceptance to the end of Cycle 86 (29 November 2000 to 17 December 2004). Since launch, we have performed a variety of GFO performance studies; an accumulative index of those studies is provided in Appendix A
Extraction of DNA from Plant and Fungus Tissues in situ
Background: When samples are collected in the field and transported to the lab, degradation of the nucleic acids contained in the samples is frequently observed. Immediate extraction and precipitation of the nucleic acids reduces degradation to a minimum, thus preserving accurate sequence information. An extraction method to obtain high quality DNA in field studies is described. Findings. DNA extracted immediately after sampling was compared to DNA extracted after allowing the sampled tissues to air dry at 21°C for 48 or 72 hours. While DNA extracted from fresh tissues exhibited little degradation, DNA extracted from all tissues exposed to 21°C air for 48 or 72 hours exhibited varying degrees of degradation. Yield was higher for extractions from fresh tissues in most cases. Four microcentrifuges were compared for DNA yield: one standard electric laboratory microcentrifuge (max rcf=16,000×g), two battery-operated microcentrifuges (max rcf=5,000 and 3,000 ×g), and one manually-operated microcentrifuge (max rcf=120×g). Yields for all centrifuges were similar. DNA extracted under simulated field conditions was similar in yield and quality to DNA extracted in the laboratory using the same equipment. Conclusions: This CTAB (cetyltrimethylammonium bromide) DNA extraction method employs battery-operated and manually-operated equipment to isolate high quality DNA in the field. The method was tested on plant and fungus tissues, and may be adapted for other types of organisms. The method produced high quality DNA in laboratory tests and under simulated field conditions. The field extraction method should prove useful for working in remote sites, where ice, dry ice, and liquid nitrogen are unavailable; where degradation is likely to occur due to the long distances between the sample site and the laboratory; and in instances where other DNA preservation and transportation methods have been unsuccessful. It may be possible to adapt this method for genomic, metagenomic, transcriptomic and metabolomic projects using samples collected in situ. © 2012 Abu Almakarem et al.; licensee BioMed Central Ltd
Helmet Exhalation Capture System (HECS) Sizing Evaluation for an Advanced Space Suit Portable Life Support System
As part of NASA s initiative to develop an advanced portable life support system (PLSS), a baseline schematic has been chosen that includes gaseous oxygen in a closed circuit ventilation configuration. Supply oxygen enters the suit at the back of the helmet and return gases pass over the astronaut s body to be extracted at the astronaut s wrists and ankles through the liquid cooling and ventilation garment (LCVG). The extracted gases are then treated using a rapid cycling amine (RCA) system for carbon dioxide and water removal and activated carbon for trace gas removal before being mixed with makeup oxygen and reintroduced into the helmet. Thermal control is provided by a suit water membrane evaporator (SWME). As an extension of the original schematic development, NASA evaluated several Helmet Exhalation Capture System (HECS) configurations as alternatives to the baseline. The HECS configurations incorporate the use of full contact masks or non-contact masks to reduce flow requirements within the PLSS ventilation subsystem. The primary scope of this study was to compare the alternatives based on mass and volume considerations; however other design issues were also briefly investigated. This paper summarizes the results of this sizing analysis task
Humidifier Development and Applicability to the Next Generation Portable Life Support System
A development effort at the NASA Johnson Space Center investigated technologies to determine whether a humidifier would be required in the Portable Life Support System (PLSS) envisioned for future exploration missions. The humidifier has been included in the baseline PLSS schematic since performance testing of the Rapid Cycle Amine (RCA) indicates that the RCA over-dries the ventilation gas stream. Performance tests of a developmental humidifier unit and commercial off-the-shelf (COTS) units were conducted in December 2009. Following these tests, NASA revisited the need for a humidifier via system analysis. Results of this investigation indicate that it is feasible to meet humidity requirements without the humidifier if other changes are made to the PLSS ventilation loop and the Liquid Cooling and Ventilation Garment (LCVG)
Customer Satisfaction Survey of Pacific Northwest National Laboratory's Technical Assistance Partners -- FY 2011
The businesses that have utilized PNNL's Technology Assistance Program were sent a survey to solicit feedback about the program and to determine what, if any, outcomes resulted from the assistance provided. As part of its small business outreach, Pacific Northwest National Laboratory (PNNL) offers technology assistance to businesses with fewer than 500 employees throughout the nation and to businesses of any size in the 2 counties that contain the Hanford site. Upon request, up to 40 staff-hours of a researcher's time can be provided to address technology issues at no charge to the requesting firm. During FY 2011, PNNL completed assistance for 54 firms. Topics of the technology assistance covered a broad range, including environment, energy, industrial processes, medical, materials, computers and software, and sensors. In FY 2011, PNNL's Technology Assistance Program (TAP) was funded by PNNL Overheads. Over the past 16 years, the Technology Assistance Program has received total funding of nearly $2.8 million from several federal and private sources
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