30 CFR 56.7053 - Moving hand-held drills.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Moving hand-held drills. 56.7053 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from one...

30 CFR 56.7053 - Moving hand-held drills.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Moving hand-held drills. 56.7053 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from one...

30 CFR 56.7053 - Moving hand-held drills.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Moving hand-held drills. 56.7053 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from one...

30 CFR 56.7053 - Moving hand-held drills.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Moving hand-held drills. 56.7053 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Drilling and Rotary Jet Piercing Drilling § 56.7053 Moving hand-held drills. Before hand-held drills are moved from one...

Hand-held radiometry: A set of notes developed for use at the Workshop of Hand-held radiometry

NASA Technical Reports Server (NTRS)

Jackson, R. D.; Pinter, P. J., Jr.; Reginato, R. J.; Idso, S. B. (Principal Investigator)

1980-01-01

A set of notes was developed to aid the beginner in hand-held radiometry. The electromagnetic spectrum is reviewed, and pertinent terms are defined. View areas of multiband radiometers are developed to show the areas of coincidence of adjacent bands. The amounts of plant cover seen by radiometers having different fields of view are described. Vegetation indices are derived and discussed. Response functions of several radiometers are shown and applied to spectrometer data taken over 12 wheat plots, to provide a comparison of instruments and bands within and among instruments. The calculation of solar time is reviewed and applied to the calculation of the local time of LANDSAT satellite overpasses for any particular location in the Northern Hemisphere. The use and misuse of hand-held infrared thermometers are discussed, and a procedure for photographic determination of plant cover is described. Some suggestions are offered concerning procedures to be followed when collecting hand-held spectral and thermal data. A list of references pertinent to hand-held radiometry is included.

Choosing a Hand-Held Inventory Device

ERIC Educational Resources Information Center

Green, Lois; Hughes, Janet; Neff, Verne; Notartomas, Trish

2008-01-01

In spring of 2006, a task force was charged to look at the feasibility of acquiring hand-held inventory devices for the Pennsylvania State University Libraries (PSUL). The task force's charge was not to look at the whole concept of doing an inventory, but rather to focus on the feasibility of acquiring hand-held devices to use in an inventory.…

Practical applications of hand-held computers in dermatology.

PubMed

Goldblum, Orin M

2002-09-01

For physicians, hand-held computers are gaining popularity as point of care reference tools. The convergence of hand-held computers, the Internet, and wireless networks will enable these devices to assume more essential roles as mobile transmitters and receivers of digital medical Information. In addition to serving as portable medical reference sources, these devices can be Internet-enabled, allowing them to communicate over wireless wide and local area networks. With enhanced wireless connectivity, hand-held computers can be used at the point of patient care for charge capture, electronic prescribing, laboratory test ordering, laboratory result retrieval, web access, e-mail communication, and other clinical and administrative tasks. Physicians In virtually every medical specialty have begun using these devices in various ways. This review of hand-held computer use in dermatology illustrates practical examples of the many different ways hand-held computers can be effectively used by the practicing dermatologist.

Hand-Held Sunphotometers for High School Student Construction and Measuring Aerosol Optical Thickness

NASA Technical Reports Server (NTRS)

Almonor, Linda; Baldwin, C.; Craig, R.; Johnson, L. P.

2000-01-01

Science education is taking the teaching of science from a traditional (lecture) approach to a multidimensional sense-making approach which allows teachers to support students by providing exploratory experiences. Using projects is one way of providing students with opportunities to observe and participate in sense-making activity. We created a learning environment that fostered inquiry-based learning. Students were engaged in a variety of Inquiry activities that enabled them to work in cooperative planning teams where respect for each other was encouraged and their ability to grasp, transform and transfer information was enhanced. Summer, 1998: An air pollution workshop was conducted for high school students in the Medgar Evers College/Middle College High School Liberty Partnership Summer Program. Students learned the basics of meteorology: structure and composition of the atmosphere and the processes that cause weather. The highlight of this workshop was the building of hand-held sunphotometers, which measure the intensity of the sunlight striking the Earth. Summer, 1999: high school students conducted a research project which measured the mass and size of ambient particulates and enhanced our ability to observe through land based measurements changes in the optical depth of ambient aerosols over Brooklyn. Students used hand held Sunphotometers to collect data over a two week period and entered it into the NASA GISS database by way of the internet.

Vibration and impulsivity analysis of hand held olive beaters.

PubMed

Deboli, Roberto; Calvo, Angela; Preti, Christian

2016-07-01

To provide more effective evaluations of hand arm vibration syndromes caused by hand held olive beaters, this study focused on two aspects: the acceleration measured at the tool pole and the analysis of the impulsivity, using the crest factor. The signals were frequency weighted using the weighting curve Wh as described in the ISO 5349-1 standard. The same source signals were also filtered by the Wh-bl filter (ISO/TS 15694), because the weighting filter Wh (unlike the Wh-bl filter) could underestimate the effect of high frequency vibration on vibration-induced finger disorders. Ten (experienced) male operators used three beater models (battery powered) in the real olive harvesting condition. High vibration total values were obtained with values never lower than 20 m(-2). Concerning the crest factor, the values ranged from 5 to more than 22. This work demonstrated that the hand held olive beaters produced high impulsive loads comparable to the industry hand held tools. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

Reliability of the hand held dynamometer in measuring muscle strength in people with interstitial lung disease.

PubMed

Dowman, Leona; McDonald, Christine F; Hill, Catherine J; Lee, Annemarie; Barker, Kathryn; Boote, Claire; Glaspole, Ian; Goh, Nicole; Southcott, Annemarie; Burge, Angela; Ndongo, Rebecca; Martin, Alicia; Holland, Anne E

2016-09-01

To evaluate the inter-rater and intra-rater reliability of the hand held dynamometer in measuring muscle strength in people with interstitial lung disease (ILD). Test retest reliability of hand-held dynamometry for elbow flexor and knee extensor strength between two independent raters and two testing sessions. Physiotherapy department within a tertiary hospital. Thirty participants with ILD of varying aetiology were included. Twenty participants completed the inter-rater reliability protocol (10 idiopathic pulmonary fibrosis, mean (SD) age 73 (10) years, 11 male) and 21 participants completed the intra-rater reliability protocol (10 idiopathic pulmonary fibrosis, mean age 71 (10) years, 11 male). Mean muscle strength (kg). Agreement between the two raters and testing sessions was analyzed using Bland-Altman plots and reliability was estimated using intraclass correlation coefficients (ICC). For elbow flexor strength there was a mean difference between raters of -0.6kg (limits of agreement (LOA) -5.6 to 4.4kg) and within raters of -0.3kg (LOA -2.8 to 2.3kg). The ICCs were 0.95 and 0.98, respectively. For knee extensor strength there was a mean difference between raters of -1.5kg (LOA -6.9 to 3.9kg) and within raters of -0.7kg (LOA -3.9 to 2.4kg). The ICCs were 0.95 and 0.97, respectively. Hand-held dynamometry is reliable in measuring elbow flexor and knee extensor strength in people with ILD. Copyright © 2015 Chartered Society of Physiotherapy. Published by Elsevier Ltd. All rights reserved.

30 CFR 56.14116 - Hand-held power tools.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand-held power tools. 56.14116 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills...

30 CFR 56.14116 - Hand-held power tools.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand-held power tools. 56.14116 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills...

30 CFR 56.14116 - Hand-held power tools.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Hand-held power tools. 56.14116 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills...

30 CFR 57.14116 - Hand-held power tools.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand-held power tools. 57.14116 Section 57... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills...

30 CFR 56.14116 - Hand-held power tools.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand-held power tools. 56.14116 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills...

30 CFR 57.14116 - Hand-held power tools.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand-held power tools. 57.14116 Section 57... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills...

30 CFR 57.14116 - Hand-held power tools.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Hand-held power tools. 57.14116 Section 57... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills...

30 CFR 56.14116 - Hand-held power tools.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Hand-held power tools. 56.14116 Section 56... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 56.14116 Hand-held power tools. (a) Power drills...

30 CFR 57.14116 - Hand-held power tools.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Hand-held power tools. 57.14116 Section 57... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills...

30 CFR 57.14116 - Hand-held power tools.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand-held power tools. 57.14116 Section 57... MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Machinery and Equipment Safety Devices and Maintenance Requirements § 57.14116 Hand-held power tools. (a) Power drills...

Reliability of measuring hip abductor strength following total knee arthroplasty using a hand-held dynamometer.

PubMed

Schache, Margaret B; McClelland, Jodie A; Webster, Kate E

2016-01-01

To investigate the test-retest reliability of measuring hip abductor strength in patients with total knee arthroplasty (TKA) using a hand-held dynamometer (HHD) with two different types of resistance: belt and manual resistance. Test-retest reliability of 30 subjects (17 female, 13 male, 71.9 ± 7.4 years old), 9.2 ± 2.7 days post TKA was measured using belt and therapist resistance. Retest reliability was calculated with intra-class coefficients (ICC3,1) and 95% confidence intervals (CI) for both the group average and the individual scores. A paired t-test assessed whether a difference existed between the belt and therapist methods of resistance. ICCs were 0.82 and 0.80 for the belt and therapist resisted methods, respectively. Hip abductor strength increases of 8 N (14%) for belt resisted and 14 N (17%) for therapist resisted measurements of the group average exceeded the 95% CI and may represent real change. For individuals, hip abductor strength increases of 33 N (72%) (belt resisted) and 57 N (79%) (therapist resisted) could be interpreted as real change. Hip abductor strength can be reliably measured using HHD in the clinical setting with the described protocol. Belt resistance demonstrated slightly higher test-retest reliability. Reliable measurement of hip abductor muscle strength in patients with TKA is important to ensure deficiencies are addressed in rehabilitation programs and function is maximized. Hip abductor strength can be reliably measured with a hand-held dynamometer in the clinical setting using manual or belt resistance.

Automated Hand-Held UXO Detection, Classification & Discrimination Sensor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bell, Thomas H.

2000-06-12

The research focused on procedures for target discrimination and classification using hand-held EMI sensors. The idea is to have a small, portable sensor that can be operated in a sweep or similar pattern in front of the operator, and that is capable of distinguishing between buried UXO and clutter on the spot. Curing Phase 1, we developed the processing techniques for distinguishing between buried UXO and clutter using the EM61-HH hand-held metal detector.

Hand held phase-shifting diffraction Moire interferometer

DOEpatents

Deason, V.A.; Ward, M.B.

1994-09-20

An interferometer is described in which a coherent beam of light is generated within a remote case and transmitted to a hand held unit tethered to said remote case, said hand held unit having optical elements for directing a pair of mutually coherent collimated laser beams at a diffraction grating. Data from the secondary or diffracted beams are then transmitted to a separate video and data acquisition system for recording and analysis for load induced deformation or for identification purposes. Means are also provided for shifting the phase of one incident beam relative to the other incident beam and being controlled from within said remote case. 4 figs.

Hand held phase-shifting diffraction moire interferometer

DOEpatents

Deason, Vance A.; Ward, Michael B.

1994-01-01

An interferometer in which a coherent beam of light is generated within a remote case and transmitted to a hand held unit tethered to said remote case, said hand held unit having optical elements for directing a pair of mutually coherent collimated laser beams at a diffraction grating. Data from the secondary or diffracted beams are then transmitted to a separate video and data acquisition system for recording and analysis for load induced deformation or for identification purposes. Means are also provided for shifting the phase of one incident beam relative to the other incident beam and being controlled from within said remote case.

Hand Held Device for Wireless Powering and Interrogation of Biomems Sensors and Actuators

NASA Technical Reports Server (NTRS)

Simons, Rainee N (Inventor); Miranda, Felix Antonio (Inventor)

2007-01-01

A compact, hand-held device for wireless powering, interrogation and data retrieval from at least one implanted sensor. The hand-held device includes an antenna for powering an implanted sensor and for receiving data from the implanted sensor to the hand-held device for at least one of storage, display or analysis. The hand-held device establishes electromagnetic coupling with a low radiating radio frequency power inductor in the implanted sensor at a predefined separation and the antenna geometry allows for the antenna to power, interrogate and retrieve data from the implanted sensor without strapping the hand-held device to a human body housing the implanted sensor The hand-held device optionally allows for activation of the implanted sensor only during interrogation and data retrieval.

Driver hand-held cellular phone use: a four-year analysis.

PubMed

Eby, David W; Vivoda, Jonathon M; St Louis, Renée M

2006-01-01

The use of hand-held cellular (mobile) phones while driving has stirred more debate, passion, and research than perhaps any other traffic safety issue in the past several years. There is ample research showing that the use of either hand-held or hands-free cellular phones can lead to unsafe driving patterns. Whether or not these performance deficits increase the risk of crash is difficult to establish, but recent studies are beginning to suggest that cellular phone use elevates crash risk. The purpose of this study was to assess changes in the rate of hand-held cellular phone use by motor-vehicle drivers on a statewide level in Michigan. This study presents the results of 13 statewide surveys of cellular phone use over a 4-year period. Hand-held cellular phone use data were collected through direct observation while vehicles were stopped at intersections and freeway exit ramps. Data were weighted to be representative of all drivers traveling during daylight hours in Michigan. The study found that driver hand-held cellular phone use has more than doubled between 2001 and 2005, from 2.7% to 5.8%. This change represents an average increase of 0.78 percentage points per year. The 5.8% use rate observed in 2005 means that at any given daylight hour, around 36,550 drivers were conversing on cellular phones while driving on Michigan roadways. The trend line fitted to these data predicts that by the year 2010, driver hand-held cellular phone use will be around 8.6%, or 55,000 drivers at any given daylight hour. These results make it clear that cellular phone use while driving will continue to be an important traffic safety issue, and highlight the importance of continued attempts to generate new ways of alleviating this potential hazard.

Promoting Physical Activity through Hand-Held Computer Technology

PubMed Central

King, Abby C.; Ahn, David K.; Oliveira, Brian M.; Atienza, Audie A.; Castro, Cynthia M.; Gardner, Christopher D.

2009-01-01

Background Efforts to achieve population-wide increases in walking and similar moderate-intensity physical activities potentially can be enhanced through relevant applications of state-of-the-art interactive communication technologies. Yet few systematic efforts to evaluate the efficacy of hand-held computers and similar devices for enhancing physical activity levels have occurred. The purpose of this first-generation study was to evaluate the efficacy of a hand-held computer (i.e., personal digital assistant [PDA]) for increasing moderate intensity or more vigorous (MOD+) physical activity levels over 8 weeks in mid-life and older adults relative to a standard information control arm. Design Randomized, controlled 8-week experiment. Data were collected in 2005 and analyzed in 2006-2007. Setting/Participants Community-based study of 37 healthy, initially underactive adults aged 50 years and older who were randomized and completed the 8-week study (intervention=19, control=18). Intervention Participants received an instructional session and a PDA programmed to monitor their physical activity levels twice per day and provide daily and weekly individualized feedback, goal setting, and support. Controls received standard, age-appropriate written physical activity educational materials. Main Outcome Measure Physical activity was assessed via the Community Healthy Activities Model Program for Seniors (CHAMPS) questionnaire at baseline and 8 weeks. Results Relative to controls, intervention participants reported significantly greater 8-week mean estimated caloric expenditure levels and minutes per week in MOD+ activity (p<0.04). Satisfaction with the PDA was reasonably high in this largely PDA-naive sample. Conclusions Results from this first-generation study indicate that hand-held computers may be effective tools for increasing initial physical activity levels among underactive adults. PMID:18201644

A hand-held EPR scanner for transcutaneous oximetry

NASA Astrophysics Data System (ADS)

Wolfson, Helen; Ahmad, Rizwan; Twig, Ygal; Blank, Aharon; Kuppusamy, Periannan

2015-03-01

Cutaneous (skin) oxygenation is an important prognostic factor for the treatment of chronic wounds, skin cancer, diabetes side effects, and limb amputation. Currently, there are no reliable methods for measuring this parameter. Oximetry, using electron paramagnetic resonance (EPR) spectroscopy, is emerging as a potential tool for clinical oximetry, including cutaneous applications. The problem with EPR oximetry, however, is that the conventional EPR design requires the use of a large magnet that can generate homogeneous field across the sample, making it unattractive for clinical practice. We present a novel approach that makes use of a miniature permanent magnet, combined with a small microwave resonator, to enable the acquisition of EPR signals from paramagnetic species placed on the skin. The instrumentation consists of a hand-held, modular, cylindrical probehead with overall dimensions of 36-mm diameter and 24-mm height, with 150-g weight. The probehead includes a Halbach array of 16 pieces (4×4×8 mm3) of Sm-Co permanent magnet and a loop-gap resonator (2.24 GHz). Preliminary measurements using a Hahn-echo pulse sequence (800 echos in 20 ms) showed a signalto- noise ratio of ~70 compared to ~435 in a homogenous magnet under identical settings. Further work is in progress to improve the performance of the probehead and to optimize the hand-held system for clinical use

Distributing Data from Desktop to Hand-Held Computers

NASA Technical Reports Server (NTRS)

Elmore, Jason L.

2005-01-01

A system of server and client software formats and redistributes data from commercially available desktop to commercially available hand-held computers via both wired and wireless networks. This software is an inexpensive means of enabling engineers and technicians to gain access to current sensor data while working in locations in which such data would otherwise be inaccessible. The sensor data are first gathered by a data-acquisition server computer, then transmitted via a wired network to a data-distribution computer that executes the server portion of the present software. Data in all sensor channels -- both raw sensor outputs in millivolt units and results of conversion to engineering units -- are made available for distribution. Selected subsets of the data are transmitted to each hand-held computer via the wired and then a wireless network. The selection of the subsets and the choice of the sequences and formats for displaying the data is made by means of a user interface generated by the client portion of the software. The data displayed on the screens of hand-held units can be updated at rates from 1 to

Development of Hand-Held Thermographic Inspection Technologies

DOT National Transportation Integrated Search

2009-09-01

This study explored the application of hand-held thermographic cameras for the detection of subsurface delaminations in concrete bridges. The goal of the research was to provide maintenance and inspection personnel with an effective tool for detectin...

Development of hand-held thermographic inspection technologies.

DOT National Transportation Integrated Search

2009-09-01

This study explored the application of hand-held thermographic cameras for the detection of subsurface delaminations in concrete : bridges. The goal of the research was to provide maintenance and inspection personnel with an effective tool for detect...

Attentionally splitting the mass distribution of hand-held rods.

PubMed

Burton, G; Turvey, M T

1991-08-01

Two experiments on the length-perception capabilities of effortful or dynamic touch differed only in terms of what the subject intended to perceive, while experimental conditions and apparatus were held constant. In each trial, a visually occluded rod was held as still as possible by the subject at an intermediate position. For two thirds of the trials, a weight was attached to the rod above or below the hand. In Experiment 1, in which the subject's task was to perceive the distance reachable with the portion of the rod forward of the hand, perceived extent was a function of the first moment of the mass distribution associated with the forward portion of the rod, and indifferent to the first moment of the entire rod. In Experiment 2, in which the task was to perceive the distance reachable with the entire rod if it was held at an end, the pattern of results was reversed. These results indicate the capability of selective sensitivity to different aspects of a hand-held object's mass distribution, without the possibility of differential exploration specific to these two tasks. Results are discussed in relation to possible roles of differential information, intention, and self-organization in the explanations of selective perceptual abilities.

Implications of Hand Held Electronic Games and Microcomputers for Informal Learning.

ERIC Educational Resources Information Center

Kee, Daniel W.

The use of hand-held electronic devices and microcomputers in places of public access and in the home are discussed. First, the different activities supported by this technology are described, with emphasis on the commonality of game playing to both hand-held devices and microcomputers. The need for research to investigate the motivational…

Hand-held internet tablets for school-based data collection.

PubMed

Denny, Simon J; Milfont, Taciano L; Utter, Jennifer; Robinson, Elizabeth M; Ameratunga, Shanthi N; Merry, Sally N; Fleming, Theresa M; Watson, Peter D

2008-07-26

In the last 20 years, researchers have been using computer self-administered questionnaires to gather data on a wide range of adolescent health related behaviours. More recently, researchers collecting data in schools have started to use smaller hand-held computers for their ease of use and portability. The aim of this study is to describe a new technology with wi-fi enabled hand-held internet tablets and to compare adolescent preferences of laptop computers or hand-held internet tablets in administering a youth health and well-being questionnaire in a school setting. A total of 177 students took part in a pilot study of a national youth health and wellbeing survey. Students were randomly assigned to internet tablets or laptops at the start of the survey and were changed to the alternate mode of administration about half-way through the questionnaire. Students at the end of the questionnaire were asked which of the two modes of administration (1) they preferred, (2) was easier to use, (3) was more private and confidential, and (4) was easier to answer truthfully. Many students expressed no preference between laptop computers or internet tablets. However, among the students who expressed a preference between laptop computers or internet tablets, the majority of students found the internet tablets more private and confidential (p < 0.001) and easier to answer questions truthfully (p < 0.001) compared to laptop computers. This study demonstrates that using wi-fi enabled hand-held internet tablets is a feasible methodology for school-based surveys especially when asking about sensitive information.

Hand-held internet tablets for school-based data collection

PubMed Central

Denny, Simon J; Milfont, Taciano L; Utter, Jennifer; Robinson, Elizabeth M; Ameratunga, Shanthi N; Merry, Sally N; Fleming, Theresa M; Watson, Peter D

2008-01-01

Background In the last 20 years, researchers have been using computer self-administered questionnaires to gather data on a wide range of adolescent health related behaviours. More recently, researchers collecting data in schools have started to use smaller hand-held computers for their ease of use and portability. The aim of this study is to describe a new technology with wi-fi enabled hand-held internet tablets and to compare adolescent preferences of laptop computers or hand-held internet tablets in administering a youth health and well-being questionnaire in a school setting. Methods A total of 177 students took part in a pilot study of a national youth health and wellbeing survey. Students were randomly assigned to internet tablets or laptops at the start of the survey and were changed to the alternate mode of administration about half-way through the questionnaire. Students at the end of the questionnaire were asked which of the two modes of administration (1) they preferred, (2) was easier to use, (3) was more private and confidential, and (4) was easier to answer truthfully. Results Many students expressed no preference between laptop computers or internet tablets. However, among the students who expressed a preference between laptop computers or internet tablets, the majority of students found the internet tablets more private and confidential (p < 0.001) and easier to answer questions truthfully (p < 0.001) compared to laptop computers. Conclusion This study demonstrates that using wi-fi enabled hand-held internet tablets is a feasible methodology for school-based surveys especially when asking about sensitive information. PMID:18710505

Intra- and Inter-Rater Reliability of the Rate of Force Development of Hip Abductor Muscles Measured by Hand-Held Dynamometer

ERIC Educational Resources Information Center

Takeda, Kazuya; Tanabe, Shigeo; Koyama, Soichiro; Nagai, Tomoko; Sakurai, Hiroaki; Kanada, Yoshikiyo; Shomoto, Koji

2018-01-01

The aim of this study was to clarify the intra- and inter-rater reliability of the rate of force development in hip abductor muscle force measurements using a hand-held dynamometer. Thirty healthy adults were separately assessed by two independent raters on two separate days. Rate of force development was calculated from the slope of the…

Computer implemented method, and apparatus for controlling a hand-held tool

NASA Technical Reports Server (NTRS)

Wagner, Kenneth William (Inventor); Taylor, James Clayton (Inventor)

1999-01-01

The invention described here in is a computer-implemented method and apparatus for controlling a hand-held tool. In particular, the control of a hand held tool is for the purpose of controlling the speed of a fastener interface mechanism and the torque applied to fasteners by the fastener interface mechanism of the hand-held tool and monitoring the operating parameters of the tool. The control is embodied in intool software embedded on a processor within the tool which also communicates with remote software. An operator can run the tool, or through the interaction of both software, operate the tool from a remote location, analyze data from a performance history recorded by the tool, and select various torque and speed parameters for each fastener.

Three-dimensional fluorescence-enhanced optical tomography using a hand-held probe based imaging system.

PubMed

Ge, Jiajia; Zhu, Banghe; Regalado, Steven; Godavarty, Anuradha

2008-07-01

Hand-held based optical imaging systems are a recent development towards diagnostic imaging of breast cancer. To date, all the hand-held based optical imagers are used to perform only surface mapping and target localization, but are not capable of demonstrating tomographic imaging. Herein, a novel hand-held probe based optical imager is developed towards three-dimensional (3-D) optical tomography studies. The unique features of this optical imager, which primarily consists of a hand-held probe and an intensified charge coupled device detector, are its ability to; (i) image large tissue areas (5 x 10 sq. cm) in a single scan, (ii) perform simultaneous multiple point illumination and collection, thus reducing the overall imaging time; and (iii) adapt to varying tissue curvatures, from a flexible probe head design. Experimental studies are performed in the frequency domain on large slab phantoms (approximately 650 ml) using fluorescence target(s) under perfect uptake (1:0) contrast ratios, and varying target depths (1-2 cm) and X-Y locations. The effect of implementing simultaneous over sequential multiple point illumination towards 3-D tomography is experimentally demonstrated. The feasibility of 3-D optical tomography studies has been demonstrated for the first time using a hand-held based optical imager. Preliminary fluorescence-enhanced optical tomography studies are able to reconstruct 0.45 ml target(s) located at different target depths (1-2 cm). However, the depth recovery was limited as the actual target depth increased, since only reflectance measurements were acquired. Extensive tomography studies are currently carried out to determine the resolution and performance limits of the imager on flat and curved phantoms.

Three-dimensional fluorescence-enhanced optical tomography using a hand-held probe based imaging system

PubMed Central

Ge, Jiajia; Zhu, Banghe; Regalado, Steven; Godavarty, Anuradha

2008-01-01

Hand-held based optical imaging systems are a recent development towards diagnostic imaging of breast cancer. To date, all the hand-held based optical imagers are used to perform only surface mapping and target localization, but are not capable of demonstrating tomographic imaging. Herein, a novel hand-held probe based optical imager is developed towards three-dimensional (3-D) optical tomography studies. The unique features of this optical imager, which primarily consists of a hand-held probe and an intensified charge coupled device detector, are its ability to; (i) image large tissue areas (5×10 sq. cm) in a single scan, (ii) perform simultaneous multiple point illumination and collection, thus reducing the overall imaging time; and (iii) adapt to varying tissue curvatures, from a flexible probe head design. Experimental studies are performed in the frequency domain on large slab phantoms (∼650 ml) using fluorescence target(s) under perfect uptake (1:0) contrast ratios, and varying target depths (1–2 cm) and X-Y locations. The effect of implementing simultaneous over sequential multiple point illumination towards 3-D tomography is experimentally demonstrated. The feasibility of 3-D optical tomography studies has been demonstrated for the first time using a hand-held based optical imager. Preliminary fluorescence-enhanced optical tomography studies are able to reconstruct 0.45 ml target(s) located at different target depths (1–2 cm). However, the depth recovery was limited as the actual target depth increased, since only reflectance measurements were acquired. Extensive tomography studies are currently carried out to determine the resolution and performance limits of the imager on flat and curved phantoms. PMID:18697559

Prediction of essential oil content of oregano by hand-held and Fourier transform NIR spectroscopy.

PubMed

Camps, Cédric; Gérard, Marianne; Quennoz, Mélanie; Brabant, Cécile; Oberson, Carine; Simonnet, Xavier

2014-05-01

In the framework of a breeding programme, the analysis of hundreds of oregano samples to determine their essential oil content (EOC) is time-consuming and expensive in terms of labour. Therefore developing a new method that is rapid, accurate and less expensive to use would be an asset to breeders. The aim of the present study was to develop a method based on near-inrared (NIR) spectroscopy to determine the EOC of oregano dried powder. Two spectroscopic approaches were compared, the first using a hand-held NIR device and the second a Fourier transform (FT) NIR spectrometer. Hand-held NIR (1000-1800 nm) measurements and partial least squares regression allowed the determination of EOC with R² and SEP values of 0.58 and 0.81 mL per 100 g dry matter (DM) respectively. Measurements with FT-NIR (1000-2500 nm) allowed the determination of EOC with R² and SEP values of 0.91 and 0.68 mL per 100 g DM respectively. RPD, RER and RPIQ values for the model implemented with FT-NIR data were satisfactory for screening application, while those obtained with hand-held NIR data were below the level required to consider the model as enough accurate for screening application. The FT-NIR approach allowed the development of an accurate model for EOC prediction. Although the hand-held NIR approach is promising, it needs additional development before it can be used in practice. © 2013 Society of Chemical Industry.

Engineering issues for hand-held sensing devices, with examples

NASA Astrophysics Data System (ADS)

Freiwald, David A.; Freiwald, Joyce

1994-03-01

It is now U.S. defense policy that there will be no new platform starts. The emphasis for platforms will be on O&M cost reduction, life-extension improvements, and force-multiplier- device upgrades. There is also an increasing emphasis on hand-held force-multiplier devices for individuals, which is the focus of this paper. Engineering issues include operations analysis, weight, cube, cost, prime power, ease of use, data storage, reliability, fault tolerance, data communications and human factors. Two examples of hand-held devices are given. Applications include USMC, Army, SOCOM, DEA, FBI, SS, Border Patrol and others. Barriers to adoption of such technology are also discussed.

Epilepsy Forewarning Using A Hand-Held Device

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hively, LM

2005-02-21

Over the last decade, ORNL has developed and patented a novel approach for forewarning of a large variety of machine and biomedical events. The present implementation uses desktop computers to analyze archival data. This report describes the next logical step in this effort, namely use of a hand-held device for the analysis.

Hand-held Calculators: Past, Present, and Future

ERIC Educational Resources Information Center

Bell, Max; And Others

1977-01-01

Recommendations of several publications with regard to the use of hand-held calculators in the mathematics curriculum are presented. Relevant portions of the NACOME and Euclid Conference reports are cited as well as a report to NSF and recommendations from an NIE/NSF conference. Recommendations support expanded use of, and research concerning,…

Hand-held photomicroscope

NASA Technical Reports Server (NTRS)

Zabower, H. R. (Inventor)

1973-01-01

A small, lightweight, compact, hand-held photomicroscope provides simultaneous viewing and photographing, with adjustable specimen illumination and exchangeable camera format. The novel photomicroscope comprises a main housing having a top plate, bottom plate, and side walls. The objective lens is mounted on the top plate in an inverted manner relative to the normal type of mounting. The specimen holder has an adjusting mechanism for adjustably moving the specimen vertically along an axis extending through the objective lens as well as transverse of the axis. The lens system serves to split the beam of light into two paths, one to the eyepiece and the other to a camera mounting. A light source is mounted on the top plate and directs light onto the specimen. A rheostat device is mounted on the top plate and coupled to the power supply for the light source so that the intensity of the light may be varied.

Balancing fast-rotating parts of hand-held machine drive

NASA Astrophysics Data System (ADS)

Korotkov, V. S.; Sicora, E. A.; Nadeina, L. V.; Yongzheng, Wang

2018-03-01

The article considers the issues related to the balancing of fast rotating parts of the hand-held machine drive including a wave transmission with intermediate rolling elements, which is constructed on the basis of the single-phase collector motor with a useful power of 1 kW and a nominal rotation frequency of 15000 rpm. The forms of balancers and their location are chosen. The method of balancing is described. The scheme for determining of residual unbalance in two correction planes is presented. Measurement results are given in tables.

Comparative Geometrical Accuracy Investigations of Hand-Held 3d Scanning Systems - AN Update

NASA Astrophysics Data System (ADS)

Kersten, T. P.; Lindstaedt, M.; Starosta, D.

2018-05-01

Hand-held 3D scanning systems are increasingly available on the market from several system manufacturers. These systems are deployed for 3D recording of objects with different size in diverse applications, such as industrial reverse engineering, and documentation of museum exhibits etc. Typical measurement distances range from 0.5 m to 4.5 m. Although they are often easy-to-use, the geometric performance of these systems, especially the precision and accuracy, are not well known to many users. First geometrical investigations of a variety of diverse hand-held 3D scanning systems were already carried out by the Photogrammetry & Laser Scanning Lab of the HafenCity University Hamburg (HCU Hamburg) in cooperation with two other universities in 2016. To obtain more information about the accuracy behaviour of the latest generation of hand-held 3D scanning systems, HCU Hamburg conducted further comparative geometrical investigations using structured light systems with speckle pattern (Artec Spider, Mantis Vision PocketScan 3D, Mantis Vision F5-SR, Mantis Vision F5-B, and Mantis Vision F6), and photogrammetric systems (Creaform HandySCAN 700 and Shining FreeScan X7). In the framework of these comparative investigations geometrically stable reference bodies were used. The appropriate reference data was acquired by measurements with two structured light projection systems (AICON smartSCAN and GOM ATOS I 2M). The comprehensive test results of the different test scenarios are presented and critically discussed in this contribution.

Reproducibility of corneal astigmatism measurements with a hand held keratometer in preschool children.

PubMed Central

Harvey, E M; Miller, J M; Dobson, V

1995-01-01

AIMS--To evaluate the overall accuracy and reproducibility of the Alcon portable autokeratometer (PAK) measurements in infants and young children. METHODS--The accuracy of the Alcon PAK in measuring toric reference surfaces (1, 3, 5, and 7 D) under various suboptimal measurement conditions was assessed, and the reproducibility of PAK measurements of corneal astigmatism in newborn infants (n = 5), children (n = 19, age 3-5 years), and adults (n = 14) was evaluated. RESULTS--Measurements of toric reference surfaces indicated (a) no significant effect of distance (17-30 mm) on accuracy of measurements, (b) no systematic relation between amount of toricity and accuracy of measurements, (c) no systematic relation between angle of measurement and accuracy, (d) no difference in accuracy of measurements when the PAK is hand held in comparison with when it is mounted, (e) no difference in accuracy of measurements when axis of toricity is oriented obliquely than when it is oriented horizontally, with respect to the PAK, and (f) a small positive bias (+0.16 D) in measurement of spherical equivalent. The PAK did not prove useful for screening newborns. However, measurements were successfully obtained from 18/19 children and 14/14 adults. There was no significant difference in median measurement deviation (deviation of a subject's five measurements from his/her mean) between children (0.21 D) and adults (0.13 D). CONCLUSIONS--The PAK produces accurate measurements of surface curvature under a variety of suboptimal conditions. Variability of PAK measurements in preschool children is small enough to suggest that it would be useful for screening for corneal astigmatism in young children. PMID:8534668

Hand-held monitor of sympathetic nervous system using salivary amylase activity and its validation by driver fatigue assessment.

PubMed

Yamaguchi, Masaki; Deguchi, Mitsuo; Wakasugi, Junichi; Ono, Shin; Takai, Noriyasu; Higashi, Tomoyuki; Mizuno, Yasufumi

2006-01-15

In order to realize a hand-held monitor of the sympathetic nervous system, we fabricated a completely automated analytical system for salivary amylase activity using a dry-chemistry system. This was made possible by the fabrication of a disposable test-strip equipped with built-in collecting and reagent papers and an automatic saliva transfer device. In order to cancel out the effects of variations in environmental temperature and pH of saliva, temperature- and pH-adjusted equations were experimentally determined, and each theoretical value was input into the memory of the hand-held monitor. Within a range of salivary amylase activity between 10 and 140 kU/l, the calibration curve for the hand-held monitor showed a coefficient with R(2)=0.97. Accordingly, it was demonstrated that the hand-held monitor enabled a user to automatically measure the salivary amylase activity with high accuracy with only 30 microl sample of saliva within a minute from collection to completion of the measurement. In order to make individual variations of salivary amylase activity negligible during driver fatigue assessment, a normalized equation was proposed. The normalized salivary amylase activity correlated with the mental and physical fatigue states. Thus, this study demonstrated that an excellent hand-held monitor with an algorithm for normalization of individuals' differences in salivary amylase activity, which could be easily and quickly used for evaluating the activity of the sympathetic nervous system at any time. Furthermore, it is suggested that the salivary amylase activity might be used as a better index for psychological research.

Hand-held computer operating system program for collection of resident experience data.

PubMed

Malan, T K; Haffner, W H; Armstrong, A Y; Satin, A J

2000-11-01

To describe a system for recording resident experience involving hand-held computers with the Palm Operating System (3 Com, Inc., Santa Clara, CA). Hand-held personal computers (PCs) are popular, easy to use, inexpensive, portable, and can share data among other operating systems. Residents in our program carry individual hand-held database computers to record Residency Review Committee (RRC) reportable patient encounters. Each resident's data is transferred to a single central relational database compatible with Microsoft Access (Microsoft Corporation, Redmond, WA). Patient data entry and subsequent transfer to a central database is accomplished with commercially available software that requires minimal computer expertise to implement and maintain. The central database can then be used for statistical analysis or to create required RRC resident experience reports. As a result, the data collection and transfer process takes less time for residents and program director alike, than paper-based or central computer-based systems. The system of collecting resident encounter data using hand-held computers with the Palm Operating System is easy to use, relatively inexpensive, accurate, and secure. The user-friendly system provides prompt, complete, and accurate data, enhancing the education of residents while facilitating the job of the program director.

78 FR 27441 - NIJ Evaluation of Hand-Held Cell Phone Detector Devices

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-10

... Hand-Held Cell Phone Detector Devices AGENCY: National Institute of Justice, Department of Justice...-held cell phone detector devices for participation in an evaluation by the NIJ Corrections Technology...-held cell phone detector devices for participation in an evaluation by the NIJ Corrections Technology...

A Cheap, Semiquantitative Hand-Held Conductivity Tester.

ERIC Educational Resources Information Center

Zawacky, Susan K. S.

1995-01-01

Describes a design for a hand-held conductivity tester powered by a 9V battery that gives semi-quantitative results for aqueous electrolyte solutions of concentrations ranging from 0.001 M to 0.1 M. The tester uses a bar-graph LED driven by an LM3914 integrated circuit to indicate the level of conductivity. A list of parts, procedures, and results…

Noise reduction techniques in the design of a pneumatic-driven hand held power tool

NASA Astrophysics Data System (ADS)

Skinner, Christian M.

2005-09-01

Pneumatic-driven hand-held power tools generate noise in the workplace. Current legislation in Europe and the USA aims at protecting workers against noise exposure. In the United States, the Occupational Safety and Health Administration (OSHA) requires that employers create a hearing conservation program if the noise exposure exceeds 85 dB(A). In the European Community under the Directive 2003/10/EC, employers are required to provide hearing protection if the noise exposure within the working environment exceeds 80 dB(A) and must require hearing protection to be worn if the noise exposure exceeds 85 dB(A). This paper examines the sources of noise which contribute to the overall noise from a hand-held power tool. A test plan was developed to identify these individual sources of noise and to determine if structure-borne noise or airborne noise is the dominant source relative to the overall noise level. The measurements were performed per International Standards Organization (ISO) 15744. This paper will describe the methodology used to identify the noise sources and reduce the overall noise of a hand-held power tool.

30 CFR 56.12033 - Hand-held electric tools.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Hand-held electric tools. 56.12033 Section 56.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56...

30 CFR 56.12033 - Hand-held electric tools.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Hand-held electric tools. 56.12033 Section 56.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56...

30 CFR 56.12033 - Hand-held electric tools.

Code of Federal Regulations, 2014 CFR

2014-07-01

... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Hand-held electric tools. 56.12033 Section 56.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56...

30 CFR 56.12033 - Hand-held electric tools.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Hand-held electric tools. 56.12033 Section 56.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56...

30 CFR 56.12033 - Hand-held electric tools.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Hand-held electric tools. 56.12033 Section 56.12033 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Electricity § 56...

Bone age maturity assessment using hand-held device

NASA Astrophysics Data System (ADS)

Ratib, Osman M.; Gilsanz, Vicente; Liu, Xiaodong; Boechat, M. I.

2004-04-01

Purpose: Assessment of bone maturity is traditionally performed through visual comparison of hand and wrist radiograph with existing reference images in textbooks. Our goal was to develop a digital index based on idealized hand Xray images that can be incorporated in a hand held computer and used for visual assessment of bone age for patients. Material and methods: Due to the large variability in bone maturation in normals, we generated a set of "ideal" images obtained by computer combinations of images from our normal reference data sets. Software for hand-held PDA devices was developed for easy navigation through the set of images and visual selection of matching images. A formula based on our statistical analysis provides the standard deviation from normal based on the chronological age of the patient. The accuracy of the program was compared to traditional interpretation by two radiologists in a double blind reading of 200 normal Caucasian children (100 boys, 100 girls). Results: Strong correlations were present between chronological age and bone age (r > 0.9) with no statistical difference between the digital and traditional assessment methods. Determinations of carpal bone maturity in adolescents was slightly more accurate using the digital system. The users did praise the convenience and effectiveness of the digital Palm Index in clinical practice. Conclusion: An idealized digital Palm Bone Age Index provides a convenient and effective alternative to conventional atlases for the assessment of skeletal maturity.

Surgical guidance system using hand-held probe with accompanying positron coincidence detector

DOE Office of Scientific and Technical Information (OSTI.GOV)

Majewski, Stanislaw; Weisenberger, Andrew G.

A surgical guidance system offering different levels of imaging capability while maintaining the same hand-held convenient small size of light-weight intra-operative probes. The surgical guidance system includes a second detector, typically an imager, located behind the area of surgical interest to form a coincidence guidance system with the hand-held probe. This approach is focused on the detection of positron emitting biomarkers with gamma rays accompanying positron emissions from the radiolabeled nuclei.

Do hand-held calorimeters provide reliable and accurate estimates of resting metabolic rate?

PubMed

Van Loan, Marta D

2007-12-01

This paper provides an overview of a new technique for indirect calorimetry and the assessment of resting metabolic rate. Information from the research literature includes findings on the reliability and validity of a new hand-held indirect calorimeter as well as use in clinical and field settings. Research findings to date are of mixed results. The MedGem instrument has provided more consistent results when compared to the Douglas bag method of measuring metabolic rate. The BodyGem instrument has been shown to be less accurate when compared to standard metabolic carts. Furthermore, when the Body Gem has been used with clinical patients or with under nourished individuals the results have not been acceptable. Overall, there is not a large enough body of evidence to definitively support the use of these hand-held devices for assessment of metabolic rate in a wide variety of clinical or research environments.

The accuracy of a hand-held navigation system in total knee arthroplasty.

PubMed

Loh, Bryan; Chen, Jerry Yongqiang; Yew, Andy Khye Soon; Pang, Hee Nee; Tay, Darren Keng Jin; Chia, Shi-Lu; Lo, Ngai Nung; Yeo, Seng Jin

2017-03-01

This study aims to evaluate the effectiveness of a new hand-held navigation system. The authors of this study hypothesize that this navigation system will improve overall lower limb alignment and implant placement without causing a delay in surgery. Two hundred consecutive patients diagnosed with tricompartmental osteoarthritis and underwent total knee arthroplasty by a senior surgeon were included in this study. One hundred patients underwent TKA using the hand-held navigation system, while the other 100 patients underwent TKA using the conventional technique. The primary outcomes of this study were the overall alignment of the lower limb and the position of the components. This was determined radiologically using the: (1) Hip-Knee-Ankle angle (HKA) for lower limb alignment; (2) Coronal Femoral-Component angle (CFA); and (3) Coronal Tibia-Component angle (CTA) for component position. Normal alignment was taken as 180° ± 3° for the HKA and 90° ± 3° for both the CFA and CTA. For the CFA, the proportion of outliers was 7 and 17% in the hand-held navigation and conventional group, respectively (p = 0.030). For the HKA and CTA, there was no difference in the proportion of outliers between the two groups. The duration of surgery was 73 ± 9 min and 87 ± 15 min in the hand-held navigation and conventional group, respectively (p < 0.001). This hand-held navigation system is an effective intraoperative tool for reducing the proportion of outliers for femoral implant placement as well as the duration of surgery. The authors conclude that it can be considered for use to check femoral implant placement intra-operatively. III.

Ultratrace detector for hand-held gas chromatography

DOEpatents

Andresen, Brian D.; Miller, Fred S.

1999-01-01

An ultratrace detector system for hand-held gas chromatography having high sensitivity, for example, to emissions generated during production of weapons, biological compounds, drugs, etc. The detector system is insensitive to water, air, helium, argon, oxygen, and C0.sub.2. The detector system is basically composed of a hand-held capillary gas chromatography (GC), an insulated heated redox-chamber, a detection chamber, and a vapor trap. For example, the detector system may use gas phase redox reactions and spectral absorption of mercury vapor. The gas chromatograph initially separates compounds that percolate through a bed of heated mercuric oxide (HgO) in a silica--or other metal--aerogel material which acts as an insulator. Compounds easily oxidized by HgO liberate atomic mercury that subsequently pass through a detection chamber which includes a detector cell, such as quartz, that is illuminated with a 254 nm ultra-violet (UV) mercury discharge lamp which generates the exact mercury absorption bands that are used to detect the liberated mercury atoms. Atomic mercury strongly absorbs 254 nm energy is therefore a specific signal for reducing compounds eluting from the capillary GC, whereafter the atomic mercury is trapped for example, in a silicon-aerogel trap.

Hand held data collection and monitoring system for nuclear facilities

DOEpatents

Brayton, D.D.; Scharold, P.G.; Thornton, M.W.; Marquez, D.L.

1999-01-26

Apparatus and method is disclosed for a data collection and monitoring system that utilizes a pen based hand held computer unit which has contained therein interaction software that allows the user to review maintenance procedures, collect data, compare data with historical trends and safety limits, and input new information at various collection sites. The system has a means to allow automatic transfer of the collected data to a main computer data base for further review, reporting, and distribution purposes and uploading updated collection and maintenance procedures. The hand held computer has a running to-do list so sample collection and other general tasks, such as housekeeping are automatically scheduled for timely completion. A done list helps users to keep track of all completed tasks. The built-in check list assures that work process will meet the applicable processes and procedures. Users can hand write comments or drawings with an electronic pen that allows the users to directly interface information on the screen. 15 figs.

Hand held data collection and monitoring system for nuclear facilities

DOEpatents

Brayton, Darryl D.; Scharold, Paul G.; Thornton, Michael W.; Marquez, Diana L.

1999-01-01

Apparatus and method is disclosed for a data collection and monitoring system that utilizes a pen based hand held computer unit which has contained therein interaction software that allows the user to review maintenance procedures, collect data, compare data with historical trends and safety limits, and input new information at various collection sites. The system has a means to allow automatic transfer of the collected data to a main computer data base for further review, reporting, and distribution purposes and uploading updated collection and maintenance procedures. The hand held computer has a running to-do list so sample collection and other general tasks, such as housekeeping are automatically scheduled for timely completion. A done list helps users to keep track of all completed tasks. The built-in check list assures that work process will meet the applicable processes and procedures. Users can hand write comments or drawings with an electronic pen that allows the users to directly interface information on the screen.

Hand-Held Ultrasonic Instrument for Reading Matrix Symbols

NASA Technical Reports Server (NTRS)

Schramm, Harry F.; Kula, John P.; Gurney, John W.; Lior, Ephraim D.

2008-01-01

A hand-held instrument that would include an ultrasonic camera has been proposed as an efficient means of reading matrix symbols. The proposed instrument could be operated without mechanical raster scanning. All electronic functions from excitation of ultrasonic pulses through final digital processing for decoding matrix symbols would be performed by dedicated circuitry within the single, compact instrument housing.

A hand-held electronic tongue based on fluorometry for taste assessment of tea.

PubMed

Chang, Kuang-Hua; Chen, Richie L C; Hsieh, Bo-Chuan; Chen, Po-Chung; Hsiao, Hsien-Yi; Nieh, Chi-Hua; Cheng, Tzong-Jih

2010-12-15

A hand-held electronic tongue was developed for determining taste levels of astringency and umami in tea infusions. The sensing principles are based on quenching the fluorescence of 3-aminophthalate by tannin, and the fluorogenic reaction of o-phthalaldehyde (OPA) with amino acids to determine astringency and umami levels, respectively. Both reactions were measured by a single fluorescence sensing system with same excitation and emission wavelengths (340/425 nm). This work describes in detail the design, fabrication, and performance evaluation of a hand-held fluorometer with an ultra-violet light emitted diode (UVLED) and a photo-detector with a filter built-in. The dimension and the weight of proposed electronic tongue prototype are only 120×60×65 mm(3) and 150 g, respectively. The detection limits of this prototype for theanine and tannic acid were 0.2 μg/ml and 1 μg/ml, respectively. Correlation coefficients of this prototype compared with a commercial fluorescence instrument are both higher than 0.995 in determinations of tannin acid and theanine. Linear detection ranges of the hand-held fluorometer for tannic acid and theanine are 1-20 μg/ml and 0.2-10 μg/ml (CV<5%, n=3), respectively. A specified taste indicator for tea, defined as ratio of umami to astringency, was adopted here to effectively distinguish flavour quality of partially fermented Oolong teas. Copyright © 2010 Elsevier B.V. All rights reserved.

Cordless hand-held optical 3D sensor

NASA Astrophysics Data System (ADS)

Munkelt, Christoph; Bräuer-Burchardt, Christian; Kühmstedt, Peter; Schmidt, Ingo; Notni, Gunther

2007-07-01

A new mobile optical 3D measurement system using phase correlation based fringe projection technique will be presented. The sensor consist of a digital projection unit and two cameras in a stereo arrangement, whereby both are battery powered. The data transfer to a base station will be done via WLAN. This gives the possibility to use the system in complicate, remote measurement situations, which are typical in archaeology and architecture. In the measurement procedure the sensor will be hand-held by the user, illuminating the object with a sequence of less than 10 fringe patterns, within a time below 200 ms. This short sequence duration was achieved by a new approach, which combines the epipolar constraint with robust phase correlation utilizing a pre-calibrated sensor head, containing two cameras and a digital fringe projector. Furthermore, the system can be utilized to acquire the all around shape of objects by using the phasogrammetric approach with virtual land marks introduced by the authors 1, 2. This way no matching procedures or markers are necessary for the registration of multiple views, which makes the system very flexible in accomplishing different measurement tasks. The realized measurement field is approx. 100 mm up to 400 mm in diameter. The mobile character makes the measurement system useful for a wide range of applications in arts, architecture, archaeology and criminology, which will be shown in the paper.

Hand-held dynamometry in patients with haematological malignancies: Measurement error in the clinical assessment of knee extension strength

PubMed Central

Knols, Ruud H; Aufdemkampe, Geert; de Bruin, Eling D; Uebelhart, Daniel; Aaronson, Neil K

2009-01-01

Background Hand-held dynamometry is a portable and inexpensive method to quantify muscle strength. To determine if muscle strength has changed, an examiner must know what part of the difference between a patient's pre-treatment and post-treatment measurements is attributable to real change, and what part is due to measurement error. This study aimed to determine the relative and absolute reliability of intra and inter-observer strength measurements with a hand-held dynamometer (HHD). Methods Two observers performed maximum voluntary peak torque measurements (MVPT) for isometric knee extension in 24 patients with haematological malignancies. For each patient, the measurements were carried out on the same day. The main outcome measures were the intraclass correlation coefficient (ICC ± 95%CI), the standard error of measurement (SEM), the smallest detectable difference (SDD), the relative values as % of the grand mean of the SEM and SDD, and the limits of agreement for the intra- and inter-observer '3 repetition average' and the 'highest value of 3 MVPT' knee extension strength measures. Results The intra-observer ICCs were 0.94 for the average of 3 MVPT (95%CI: 0.86–0.97) and 0.86 for the highest value of 3 MVPT (95%CI: 0.71–0.94). The ICCs for the inter-observer measurements were 0.89 for the average of 3 MVPT (95%CI: 0.75–0.95) and 0.77 for the highest value of 3 MVPT (95%CI: 0.54–0.90). The SEMs for the intra-observer measurements were 6.22 Nm (3.98% of the grand mean (GM) and 9.83 Nm (5.88% of GM). For the inter-observer measurements, the SEMs were 9.65 Nm (6.65% of GM) and 11.41 Nm (6.73% of GM). The SDDs for the generated parameters varied from 17.23 Nm (11.04% of GM) to 27.26 Nm (17.09% of GM) for intra-observer measurements, and 26.76 Nm (16.77% of GM) to 31.62 Nm (18.66% of GM) for inter-observer measurements, with similar results for the limits of agreement. Conclusion The results indicate that there is acceptable relative reliability for

Intrinsic fluorescence based in-vivo detection of cervical precancer with hand held prototype device

NASA Astrophysics Data System (ADS)

Meena, Bharat Lal; Raikwar, Akanksha; Pandey, Kiran; Agarwal, Asha; Pantola, Chayanika; Pradhan, Asima

2018-02-01

A prototype device (hand held probe) designed and fabricated in the lab has been tested for cervical precancer detection using intrinsic fluorescence. The intrinsic fluorescence gets strongly modulated by the interplay of scattering and absorption. This masks valuable biochemical information which is present in the intrinsic fluorescence. These distortion effects can be minimized by normalizing the polarized fluorescence spectra by the polarized elastic scattering spectra. The measurements have been made with a in-house fabricated device using a 405 nm diode laser and white light source respectively. 166 sites of different grades of cervical pre-cancer biopsy samples (CIN I and CIN II) (CIN: cervical intraepithelial neoplastic) have been discriminated from 29 sites of normal biopsy samples using principal component analysis (PCA) based linear discriminant analysis (LDA). The sensitivity and specificity for discrimination of normal samples from CIN I are found to be 99% and 96% respectively. Further the normal samples can be discriminated from CIN II samples with 96% sensitivity and 96% specificity. Based on these promising ex-vivo results an in-vivo study on patients has been initiated in the hospital. The hand held device built in-house shows promise as a useful tool for in vivo cervical precancer detection by polarized fluorescence. Preliminary in-vivo results on 10 patients indicate the efficacy of the hand held device for screening cervical precancers using intrinsic fluorescence.

Hand-held analyser based on microchip electrophoresis with contactless conductivity detection for measurement of chemical warfare agent degradation products

NASA Astrophysics Data System (ADS)

Duran, Karolina-Petkovic; Zhu, Yonggang; Chen, Chuanpin; Swallow, Anthony; Stewart, Robert; Hoobin, Pam; Leech, Patrick; Ovenden, Simon

2008-12-01

This paper reports on the development of a hand-held device for on-site detection of organophosphonate nerve agent degradation products. This field-deployable analyzer relies on efficient microchip electrophoresis separation of alkyl methylphosphonic acids and their sensitive contactless conductivity detection. Miniaturized, low-powered design is coupled with promising analytical performance for separating the breakdown products of chemical warfare agents such as Soman, Sarin and VX . The detector has a detection limit of about 10 μg/mL and has a good linear response in the range 10-300 μg/mL concentration range. Applicability to environmental samples is demonstrated .The new hand-held analyzer offers great promise for converting conventional ion chromatography or capillary electrophoresis sophisticated systems into a portable forensic laboratory for faster, simpler and more reliable on-site screening.

Hand-held optical imager (Gen-2): improved instrumentation and target detectability

PubMed Central

Gonzalez, Jean; DeCerce, Joseph; Erickson, Sarah J.; Martinez, Sergio L.; Nunez, Annie; Roman, Manuela; Traub, Barbara; Flores, Cecilia A.; Roberts, Seigbeh M.; Hernandez, Estrella; Aguirre, Wenceslao; Kiszonas, Richard

2012-01-01

Abstract. Hand-held optical imagers are developed by various researchers towards reflectance-based spectroscopic imaging of breast cancer. Recently, a Gen-1 handheld optical imager was developed with capabilities to perform two-dimensional (2-D) spectroscopic as well as three-dimensional (3-D) tomographic imaging studies. However, the imager was bulky with poor surface contact (∼30%) along curved tissues, and limited sensitivity to detect targets consistently. Herein, a Gen-2 hand-held optical imager that overcame the above limitations of the Gen-1 imager has been developed and the instrumentation described. The Gen-2 hand-held imager is less bulky, portable, and has improved surface contact (∼86%) on curved tissues. Additionally, the forked probe head design is capable of simultaneous bilateral reflectance imaging of both breast tissues, and also transillumination imaging of a single breast tissue. Experimental studies were performed on tissue phantoms to demonstrate the improved sensitivity in detecting targets using the Gen-2 imager. The improved instrumentation of the Gen-2 imager allowed detection of targets independent of their location with respect to the illumination points, unlike in Gen-1 imager. The developed imager has potential for future clinical breast imaging with enhanced sensitivity, via both reflectance and transillumination imaging. PMID:23224163

System design of a hand-held mobile robot for craniotomy.

PubMed

Kane, Gavin; Eggers, Georg; Boesecke, Robert; Raczkowsky, Jörg; Wörn, Heinz; Marmulla, Rüdiger; Mühling, Joachim

2009-01-01

This contribution reports the development and initial testing of a Mobile Robot System for Surgical Craniotomy, the Craniostar. A kinematic system based on a unicycle robot is analysed to provide local positioning through two spiked wheels gripping directly onto a patients skull. A control system based on a shared control system between both the Surgeon and Robot is employed in a hand-held design that is tested initially on plastic phantom and swine skulls. Results indicate that the system has substantially lower risk than present robotically assisted craniotomies, and despite being a hand-held mobile robot, the Craniostar is still capable of sub-millimetre accuracy in tracking along a trajectory and thus achieving an accurate transfer of pre-surgical plan to the operating room procedure, without the large impact of current medical robots based on modified industrial robots.

Continuing Measurements of CO2 Crystals with a Hand-Held 35 GHz Radiometer

NASA Technical Reports Server (NTRS)

Foster, J.; Chang, A.; Hall, D.; Tait, A.; Wergin, W.; Erbe, E.

2000-01-01

In order to increase our knowledge of the Martian polar caps, an improved understanding of the behavior of both frozen H2O and CO2 in different parts of the electromagnetic spectrum is needed. The thermal microwave part of the spectrum has received relatively little attention compared to the visible and infrared wavelengths. A simple experiment to measure the brightness temperature of frozen CO2 was first performed in the winter of 1998 using a 35 GHz radiometer. in experiments performed during the winter of 1999 and 2000, passive microwave radiation emanating from within layers of manufactured CO2 (dry ice) crystals was again measured with a 35 GHz handheld radiometer. Both large (0.8 cm) and small (0.3 cm) cylindrical-shaped dry ice pellets, at a temperature of 197 K (-76 C), were measured. A 1 sq m plate of aluminum sheet metal was positioned beneath the dry ice so that microwave emissions from the underlying soil layers would be minimized. Non-absorbing foam was positioned around the sides of the plate in order to keep the dry ice in place and to assure that the incremental deposits were level. Thirty-five GHz measurements of this plate were made through the dry ice deposits in the following way. Layers of dry ice were built up and measurements were repeated for the increasing CO2 pack. First, 7 cm of large CO2 pellets were poured onto the sheet metal plate, then an additional 7 cm were added, and finally, 12 cm were added on top of the 14 cm base. Hand-held 35 GHz measurements were made each time the thickness of the deposit was increased. The same process was repeated for the smaller grain pellets. Furthermore, during the past winter, 35 GHz measurements were taken of a 25 kg (27 cm x 27 cm x 27 cm) solid cube Of CO2, which was cut in half and then re-measured. Additional information is contained in the original extended abstract.

Hand-held indirect calorimeter offers advantages compared with prediction equations, in a group of overweight women, to determine resting energy expenditures and estimated total energy expenditures during research screening.

PubMed

Spears, Karen E; Kim, Hyunsook; Behall, Kay M; Conway, Joan M

2009-05-01

To compare standardized prediction equations to a hand-held indirect calorimeter in estimating resting energy and total energy requirements in overweight women. Resting energy expenditure (REE) was measured by hand-held indirect calorimeter and calculated by prediction equations Harris-Benedict, Mifflin-St Jeor, World Health Organization/Food and Agriculture Organization/United Nations University (WHO), and Dietary Reference Intakes (DRI). Physical activity level, assessed by questionnaire, was used to estimate total energy expenditure (TEE). Subjects (n=39) were female nonsmokers older than 25 years of age with body mass index more than 25. Repeated measures analysis of variance, Bland-Altman plot, and fitted regression line of difference. A difference within +/-10% of two methods indicated agreement. Significant proportional bias was present between hand-held indirect calorimeter and prediction equations for REE and TEE (P<0.01); prediction equations overestimated at lower values and underestimated at higher values. Mean differences (+/-standard error) for REE and TEE between hand-held indirect calorimeter and Harris-Benedict were -5.98+/-46.7 kcal/day (P=0.90) and 21.40+/-75.7 kcal/day (P=0.78); between hand-held indirect calorimeter and Mifflin-St Jeor were 69.93+/-46.7 kcal/day (P=0.14) and 116.44+/-75.9 kcal/day (P=0.13); between hand-held indirect calorimeter and WHO were -22.03+/-48.4 kcal/day (P=0.65) and -15.8+/-77.9 kcal/day (P=0.84); and between hand-held indirect calorimeter and DRI were 39.65+/-47.4 kcal/day (P=0.41) and 56.36+/-85.5 kcal/day (P=0.51). Less than 50% of predictive equation values were within +/-10% of hand-held indirect calorimeter values, indicating poor agreement. A significant discrepancy between predicted and measured energy expenditure was observed. Further evaluation of hand-held indirect calorimeter research screening is needed.

Hand-held cell phone use while driving legislation and observed driver behavior among population sub-groups in the United States.

PubMed

Rudisill, Toni M; Zhu, Motao

2017-05-12

Cell phone use behaviors are known to vary across demographic sub-groups and geographic locations. This study examined whether universal hand-held calling while driving bans were associated with lower road-side observed hand-held cell phone conversations across drivers of different ages (16-24, 25-59, ≥60 years), sexes, races (White, African American, or other), ruralities (suburban, rural, or urban), and regions (Northeast, Midwest, South, and West). Data from the 2008-2013 National Occupant Protection Use Survey were merged with states' cell phone use while driving legislation. The exposure was presence of a universal hand-held cell phone ban at time of observation. Logistic regression was used to assess the odds of drivers having a hand-held cell phone conversation. Sub-groups differences were assessed using models with interaction terms. When universal hand-held cell phone bans were effective, hand-held cell phone conversations were lower across all driver demographic sub-groups and regions. Sub-group differences existed among the sexes (p-value, <0.0001) and regions (p-value, 0.0003). Compared to states without universal hand-held cell phone bans, the adjusted odds ratio (aOR) of a driver hand-held phone conversation was 0.34 [95% confidence interval (CI): 0.28, 0.41] for females versus 0.47 (CI 0.40, 0.55) for males and 0.31 (CI 0.25, 0.38) for drivers in Western states compared to 0.47 (CI 0.30, 0.72) in the Northeast and 0.50 (CI 0.38, 0.66) in the South. The presence of universal hand-held cell phone bans were associated lower hand-held cell phone conversations across all driver sub-groups and regions. Hand-held phone conversations were particularly lower among female drivers and those from Western states when these bans were in effect. Public health interventions concerning hand-held cell phone use while driving could reasonably target all drivers.

Maintaining radiation exposures as low as reasonably achievable (ALARA) for dental personnel operating portable hand-held x-ray equipment.

PubMed

McGiff, Thomas J; Danforth, Robert A; Herschaft, Edward E

2012-08-01

Clinical experience indicates that newly available portable hand-held x-ray units provide advantages compared to traditional fixed properly installed and operated x-ray units in dental radiography. However, concern that hand-held x-ray units produce higher operator doses than fixed x-ray units has caused regulatory agencies to mandate requirements for use of hand-held units that go beyond those recommended by the manufacturer and can discourage the use of this technology. To assess the need for additional requirements, a hand-held x-ray unit and a pair of manikins were used to measure the dose to a simulated operator under two conditions: exposures made according to the manufacturer's recommendations and exposures made according to manufacturer's recommendation except for the removal of the x-ray unit's protective backscatter shield. Dose to the simulated operator was determined using an array of personal dosimeters and a pair of pressurized ion chambers. The results indicate that the dose to an operator of this equipment will be less than 0.6 mSv y⁻¹ if the device is used according to the manufacturer's recommendations. This suggests that doses to properly trained operators of well-designed, hand-held dental x-ray units will be below 1.0 mSv y⁻¹ (2% of the annual occupational dose limit) even if additional no additional operational requirements are established by regulatory agencies. This level of annual dose is similar to those reported as typical dental personnel using fixed x-ray units and appears to satisfy the ALARA principal for this class of occupational exposures.

A Novel Hand-Held Optical Imager with Real-Time Coregistration Facilities Toward Diagnostic Mammography

DTIC Science & Technology

2011-01-01

Journal Publications (1) S.J. Erickson, S.L. Martinez, J. Gonzalez, L. Caldera , and A. Godavarty. “Improved detection limits using a hand-held...Erickson, S. Martinez, J. Gonzalez, L. Caldera , and A. Godavarty. “Non- invasive Diagnostic Breast Imaging using a Hand-held Optical Imager...Proceedings of the 14th World Multi-Conference on Systems, Cybernetics and Informatics, 2010. (4) S.J. Erickson, S. Martinez, L. Caldera , and A

The reliability and validity of measurements of human dental casts made by an intra-oral 3D scanner, with conventional hand-held digital callipers as the comparison measure.

PubMed

Rajshekar, Mithun; Julian, Roberta; Williams, Anne-Marie; Tennant, Marc; Forrest, Alex; Walsh, Laurence J; Wilson, Gary; Blizzard, Leigh

2017-09-01

Intra-oral 3D scanning of dentitions has the potential to provide a fast, accurate and non-invasive method of recording dental information. The aim of this study was to assess the reliability of measurements of human dental casts made using a portable intra-oral 3D scanner appropriate for field use. Two examiners each measured 84 tooth and 26 arch features of 50 sets of upper and lower human dental casts using digital hand-held callipers, and secondly using the measuring tool provided with the Zfx IntraScan intraoral 3D scanner applied to the virtual dental casts. The measurements were repeated at least one week later. Reliability and validity were quantified concurrently by calculation of intra-class correlation coefficients (ICC) and standard errors of measurement (SEM). The measurements of the 110 landmark features of human dental casts made using the intra-oral 3D scanner were virtually indistinguishable from measurements of the same features made using conventional hand-held callipers. The difference of means as a percentage of the average of the measurements by each method ranged between 0.030% and 1.134%. The intermethod SEMs ranged between 0.037% and 0.535%, and the inter-method ICCs ranged between 0.904 and 0.999, for both the upper and the lower arches. The inter-rater SEMs were one-half and the intra-method/rater SEMs were one-third of the inter-method values. This study demonstrates that the Zfx IntraScan intra-oral 3D scanner with its virtual on-screen measuring tool is a reliable and valid method for measuring the key features of dental casts. Copyright © 2017 Elsevier B.V. All rights reserved.

Thresholds of whole-blood β-hydroxybutyrate and glucose concentrations measured with an electronic hand-held device to identify ovine hyperketonemia.

PubMed

Pichler, M; Damberger, A; Schwendenwein, I; Gasteiner, J; Drillich, M; Iwersen, M

2014-03-01

Metabolic disorders, especially hyperketonemia, are very common in dairy sheep. The whole-blood concentrations of β-hydroxybutyrate (BHBA) and glucose can be determined by commercially available electronic hand-held devices, which are used in human medicine and for the detection of ketosis in dairy cows. The aim of this study was to evaluate the suitability of the hand-held device Precision Xceed (PX; Abbott Diabetes Care Inc., Abbott Park, IL) to detect hyperketonemia in ewes. An additional objective of this study was to evaluate the agreement between samples obtained by minimal invasive venipuncture of an ear vein and measurements of whole-blood samples from the jugular vein (vena jugularis, v. jug.). Blood samples taken from the v. jug. were collected from 358 ewes on 4 different farms. These samples and a blood drop obtained from an ear vein were analyzed simultaneously on farm with the PX. For method comparison, the samples obtained from the v. jug. were also analyzed by standard methods, which served as the gold standard at the Central Laboratory of the University of Veterinary Medicine Vienna, Austria. The correlation coefficients between the serum BHBA concentration and the concentrations measured with the hand-held meter in the whole blood from an ear vein and the v. jug. were 0.94 and 0.96, respectively. The correlation coefficients of plasma and whole-blood glucose concentration were 0.68 for the v. jug. and 0.47 for the ear vein. The mean glucose concentration was significantly lower in animals classified as hyperketonemic (BHBA ≥ 1.6 mmol/L) compared with healthy ewes. Whole-blood concentrations of BHBA and glucose measured with the PX from v. jug. showed a constant negative bias of 0.15 mmol/L and 8.4 mg/dL, respectively. Hence, a receiver operating characteristic analysis was performed to determine thresholds for the PX to detect hyperketonemia in ewes. This resulted in thresholds for moderate ketosis of BHBA concentrations of 0.7 mmol/L in blood

Comparative Geometrical Investigations of Hand-Held Scanning Systems

NASA Astrophysics Data System (ADS)

Kersten, T. P.; Przybilla, H.-J.; Lindstaedt, M.; Tschirschwitz, F.; Misgaiski-Hass, M.

2016-06-01

An increasing number of hand-held scanning systems by different manufacturers are becoming available on the market. However, their geometrical performance is little-known to many users. Therefore the Laboratory for Photogrammetry & Laser Scanning of the HafenCity University Hamburg has carried out geometrical accuracy tests with the following systems in co-operation with the Bochum University of Applied Sciences (Laboratory for Photogrammetry) as well as the Humboldt University in Berlin (Institute for Computer Science): DOTProduct DPI-7, Artec Spider, Mantis Vision F5 SR, Kinect v1 + v2, Structure Sensor and Google's Project Tango. In the framework of these comparative investigations geometrically stable reference bodies were used. The appropriate reference data were acquired by measurement with two structured light projection systems (AICON smartSCAN and GOM ATOS I 2M). The comprehensive test results of the different test scenarios are presented and critically discussed in this contribution.

Use of a hand-held meter for detecting subclinical ketosis in dairy cows.

PubMed

Voyvoda, Huseyin; Erdogan, Hasan

2010-12-01

The Optium Xceed is a new hand-held meter for determining blood β-hydroxybutyrate (BHBA) and glucose in human medicine. The objective of this study was to compare BHBA and glucose results obtained using the hand-held meter with those results made with a laboratory method and to evaluate its usefulness as a cowside test in the diagnosis of subclinical ketosis (SCK) in dairy cows. Seventy-eight blood samples from clinically healthy Holstein cows between 5 and 60 days post-calving were analysed. BHBA and glucose values were significantly higher with the hand-held meter versus laboratory methods. Correlation coefficients (r) for BHBA and glucose with the Optium Xceed versus laboratory methods were 0.97 and 0.63, respectively. Based on Bland-Altman plot and Passing-Bablok regression, agreement between two methods was good for BHBA but the agreement for glucose was only fair. When SCK was defined as plasma BHBA levels ≥ 1200 μmol/L, the sensitivity and specificity of the hand-held meter ketone testing in determining SCK were 85% and 94%, respectively. Raising the threshold of the laboratory method to ≥ 1400 μmol/L, the sensitivity and specificity incremented to 0.90 and 0.98, respectively. In conclusion, the blood ketone-monitoring device can be used as a rapid and reliable diagnostic test to detect SCK under field conditions. Copyright © 2010 Elsevier Ltd. All rights reserved.

Combining heterogenous features for 3D hand-held object recognition

NASA Astrophysics Data System (ADS)

Lv, Xiong; Wang, Shuang; Li, Xiangyang; Jiang, Shuqiang

2014-10-01

Object recognition has wide applications in the area of human-machine interaction and multimedia retrieval. However, due to the problem of visual polysemous and concept polymorphism, it is still a great challenge to obtain reliable recognition result for the 2D images. Recently, with the emergence and easy availability of RGB-D equipment such as Kinect, this challenge could be relieved because the depth channel could bring more information. A very special and important case of object recognition is hand-held object recognition, as hand is a straight and natural way for both human-human interaction and human-machine interaction. In this paper, we study the problem of 3D object recognition by combining heterogenous features with different modalities and extraction techniques. For hand-craft feature, although it reserves the low-level information such as shape and color, it has shown weakness in representing hiconvolutionalgh-level semantic information compared with the automatic learned feature, especially deep feature. Deep feature has shown its great advantages in large scale dataset recognition but is not always robust to rotation or scale variance compared with hand-craft feature. In this paper, we propose a method to combine hand-craft point cloud features and deep learned features in RGB and depth channle. First, hand-held object segmentation is implemented by using depth cues and human skeleton information. Second, we combine the extracted hetegerogenous 3D features in different stages using linear concatenation and multiple kernel learning (MKL). Then a training model is used to recognize 3D handheld objects. Experimental results validate the effectiveness and gerneralization ability of the proposed method.

System stability and calibrations for hand-held electromagnetic frequency domain instruments

NASA Astrophysics Data System (ADS)

Saksa, Pauli J.; Sorsa, Joona

2017-05-01

There are a few multiple-frequency domain electromagnetic induction (EMI) hand-held rigid boom systems available for shallow geophysical resistivity investigations. They basically measure secondary field real and imaginary components after the system calibrations. One multiple-frequency system, the EMP-400 Profiler from Geophysical Survey Systems Inc., was tested for system calibrations, stability and various effects present in normal measurements like height variation, tilting, signal stacking and time stability. Results indicated that in test conditions, repeatable high-accuracy imaginary component values can be recorded for near-surface frequency soundings. In test conditions, real components are also stable but vary strongly in normal surveying measurements. However, certain calibration issues related to the combination of user influence and measurement system height were recognised as an important factor in reducing for data errors and for further processing like static offset corrections.

Hand-held digital books in radiology: convenient access to information.

PubMed

D'Alessandro, M P; Galvin, J R; Santer, D M; Erkonen, W E

1995-02-01

Radiologists need constant, convenient access to current information throughout the course of their daily work. Today most learning in radiology is obtained from the printed word in books, journals, and teaching files, supplemented by the spoken word in lectures and conferences. Although learning from printed material and lectures has been proved efficacious over time, these media share the disadvantage of not being conveniently available for reference during the course of daily work at the alternator or in the examination room when accurate and up-to-date information is needed the most. As a result, many important questions about patient care go unanswered. We have developed a technique--hand-held digital books--to lower this barrier to searching and retrieval. When radiologists have a digital library that can be carried with them, they will be able to incorporate current radiology information into their daily decision making. We describe a technique for creating hand-held digital books and their future use in radiology.

Development of dual sensor hand-held detector

NASA Astrophysics Data System (ADS)

Sezgin, Mehmet

2010-04-01

In this paper hand-held dual sensor detector development requirements are considered dedicated to buried object detection. Design characteristics of such a system are categorized and listed. Hardware and software structures, ergonomics, user interface, environmental and EMC/EMI tests to be applied and performance test issues are studied. Main properties of the developed system (SEZER) are presented, which contains Metal Detector (MD) and Ground Penetrating Radar (GPR). The realized system has ergonomic structure and can detect both metallic and non-metallic buried objects. Moreover classification of target is possible if it was defined to the signal processing software in learning phase.

49 CFR 392.82 - Using a hand-held mobile telephone.

Code of Federal Regulations, 2012 CFR

2012-10-01

...) Definitions. For the purpose of this section only, driving means operating a commercial motor vehicle on a... SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS DRIVING OF.... (a)(1) No driver shall use a hand-held mobile telephone while driving a CMV. (2) No motor carrier...

49 CFR 392.82 - Using a hand-held mobile telephone.

Code of Federal Regulations, 2014 CFR

2014-10-01

...) Definitions. For the purpose of this section only, driving means operating a commercial motor vehicle on a... SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS DRIVING OF.... (a)(1) No driver shall use a hand-held mobile telephone while driving a CMV. (2) No motor carrier...

49 CFR 392.82 - Using a hand-held mobile telephone.

Code of Federal Regulations, 2013 CFR

2013-10-01

...) Definitions. For the purpose of this section only, driving means operating a commercial motor vehicle on a... SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION FEDERAL MOTOR CARRIER SAFETY REGULATIONS DRIVING OF.... (a)(1) No driver shall use a hand-held mobile telephone while driving a CMV. (2) No motor carrier...

Online Responses towards Parental Rearing Styles Regarding Hand-Held Devices

ERIC Educational Resources Information Center

Geng, Gretchen; Disney, Leigh

2014-01-01

This article reviewed the literature on parental rearing styles and used responses from an online discussion forum to investigate people's opinions towards parental rearing styles and strategies when children use hand-held devices. Critical discourse analysis (CDA) was used as an analysis method via micro, meso and macro multi-level…

Hand-held optoacoustic probe for three-dimensional imaging of human morphology and function

NASA Astrophysics Data System (ADS)

Deán-Ben, X. Luís.; Razansky, Daniel

2014-03-01

We report on a hand-held imaging probe for real-time optoacoustic visualization of deep tissues in three dimensions. The proposed solution incorporates a two-dimensional array of ultrasonic sensors densely distributed on a spherical surface, whereas illumination is performed coaxially through a cylindrical cavity in the array. Visualization of three-dimensional tomographic data at a frame rate of 10 images per second is enabled by parallel recording of 256 time-resolved signals for each individual laser pulse along with a highly efficient GPUbased real-time reconstruction. A liquid coupling medium (water), enclosed in a transparent membrane, is used to guarantee transmission of the optoacoustically generated waves to the ultrasonic detectors. Excitation at multiple wavelengths further allows imaging spectrally distinctive tissue chromophores such as oxygenated and deoxygenated haemoglobin. The performance is showcased by video-rate tracking of deep tissue vasculature and three-dimensional measurements of blood oxygenenation in a healthy human volunteer. The flexibility provided by the hand-held hardware design, combined with the real-time operation, makes the developed platform highly usable for both small animal research and clinical imaging in multiple indications, including cancer, inflammation, skin and cardiovascular diseases, diagnostics of lymphatic system and breast

How to use hand-held computers to evaluate wood drying.

Treesearch

Howard N. Rosen; Darrell S. Martin

1985-01-01

Techniques have been developed to evaluate end generate wood drying curves with hand-held computers (3-5K memory). Predictions of time to dry to a specific moisture content, drying rates, and other characteristics of wood drying curves can be made. The paper describes the development of programs and illustrates their use.

Intrarater reliability of hand held dynamometry in measuring lower extremity isometric strength using a portable stabilization device.

PubMed

Jackson, Steven M; Cheng, M Samuel; Smith, A Russell; Kolber, Morey J

2017-02-01

Hand held dynamometry (HHD) is a more objective way to quantify muscle force production (MP) compared to traditional manual muscle testing. HHD reliability can be negatively impacted by both the strength of the tester and the subject particularly in the lower extremities due to larger muscle groups. The primary aim of this investigation was to assess intrarater reliability of HHD with use of a portable stabilization device for lower extremity MP in an athletic population. Isometric lower extremity strength was measured for bilateral lower extremities including hip abductors, external rotators, adductors, knee extensors, and ankle plantar flexors was measured in a sample of healthy recreational runners (8 male, 7 females, = 30 limbs) training for a marathon. These measurements were assessed using an intrasession intrarater reliability design. Intraclass correlation coefficients (ICC) were calculated using 3,1 model based on the single rater design. The standard error of measurement (SEM) for each muscle group was also calculated. ICC were excellent ranging from ICC (3,1) = 0.93-0.98 with standard error of measurements ranging from 0.58 to 17.2 N. This study establishes the use of a HHD with a portable stabilization device as demonstrating good reliability within testers for measuring lower extremity muscle performance in an active healthy population. Copyright © 2016 Elsevier Ltd. All rights reserved.

The Weak Link HP-41C hand-held calculator program

Treesearch

Ross A. Phillips; Penn A. Peters; Gary D. Falk

1982-01-01

The Weak Link hand-held calculator program (HP-41C) quickly analyzes a system for logging production and costs. The production equations model conventional chain saw, skidder, loader, and tandemaxle truck operations in eastern mountain areas. Production of each function of the logging system may be determined so that the system may be balanced for minimum cost. The...

Evaluation of U.S. Commercial-Off-the-Shelf Hand-Held Assays to Detect Opiate Pain Reliever Compounds in Multiple Biofluids

DTIC Science & Technology

2016-09-01

EVALUATION OF U.S. COMMERCIAL-OFF-THE-SHELF HAND-HELD ASSAYS TO DETECT OPIATE PAIN RELIEVER COMPOUNDS IN...Commercial-Off-the-Shelf Hand-Held Assays to Detect Opiate Pain Reliever Compounds in Multiple Biofluids 5a. CONTRACT NUMBER 5b. GRANT NUMBER R...study, we evaluated the potential for several U.S. commercial-off-the-shelf (COTS) hand-held assays (HHAs) to detect members of the opiate pain reliever

Hand-Held EMI Sensor Combined with Inertial Positioning for Cued UXO Discrimination - APG Standardized UXO Test Site

DTIC Science & Technology

2013-04-01

Measurement Tracking System (SAINT) with an advanced hand-held, time-domain electromagnetic sensor (TEM-HH) and document classification performance at...rejecting 77% of the clutter. 15. SUBJECT TERMS EMI, electromagnetic induction, UXO classification, UXO, IMU, inertial measurement unit, 16. SECURITY...U c. THIS PAGE U UU 19b. TELEPHONE NUMBER (include area code) 919-677-1560 Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std. Z39.18

Evaluation of a focussed protocol for hand-held echocardiography and computer-assisted auscultation in detecting latent rheumatic heart disease in scholars.

PubMed

Zühlke, Liesl J; Engel, Mark E; Nkepu, Simpiwe; Mayosi, Bongani M

2016-08-01

Introduction Echocardiography is the diagnostic test of choice for latent rheumatic heart disease. The utility of echocardiography for large-scale screening is limited by high cost, complex diagnostic protocols, and time to acquire multiple images. We evaluated the performance of a brief hand-held echocardiography protocol and computer-assisted auscultation in detecting latent rheumatic heart disease with or without pathological murmur. A total of 27 asymptomatic patients with latent rheumatic heart disease based on the World Heart Federation criteria and 66 healthy controls were examined by standard cardiac auscultation to detect pathological murmur. Hand-held echocardiography using a focussed protocol that utilises one view - that is, the parasternal long-axis view - and one measurement - that is, mitral regurgitant jet - and a computer-assisted auscultation utilising an automated decision tool were performed on all patients. The sensitivity and specificity of computer-assisted auscultation in latent rheumatic heart disease were 4% (95% CI 1.0-20.4%) and 93.7% (95% CI 84.5-98.3%), respectively. The sensitivity and specificity of the focussed hand-held echocardiography protocol for definite rheumatic heart disease were 92.3% (95% CI 63.9-99.8%) and 100%, respectively. The test reliability of hand-held echocardiography was 98.7% for definite and 94.7% for borderline disease, and the adjusted diagnostic odds ratios were 1041 and 263.9 for definite and borderline disease, respectively. Computer-assisted auscultation has extremely low sensitivity but high specificity for pathological murmur in latent rheumatic heart disease. Focussed hand-held echocardiography has fair sensitivity but high specificity and diagnostic utility for definite or borderline rheumatic heart disease in asymptomatic patients.

Gen-2 hand-held optical imager towards cancer imaging: reflectance and transillumination phantom studies.

PubMed

Gonzalez, Jean; Roman, Manuela; Hall, Michael; Godavarty, Anuradha

2012-01-01

Hand-held near-infrared (NIR) optical imagers are developed by various researchers towards non-invasive clinical breast imaging. Unlike these existing imagers that can perform only reflectance imaging, a generation-2 (Gen-2) hand-held optical imager has been recently developed to perform both reflectance and transillumination imaging. The unique forked design of the hand-held probe head(s) allows for reflectance imaging (as in ultrasound) and transillumination or compressed imaging (as in X-ray mammography). Phantom studies were performed to demonstrate two-dimensional (2D) target detection via reflectance and transillumination imaging at various target depths (1-5 cm deep) and using simultaneous multiple point illumination approach. It was observed that 0.45 cc targets were detected up to 5 cm deep during transillumination, but limited to 2.5 cm deep during reflectance imaging. Additionally, implementing appropriate data post-processing techniques along with a polynomial fitting approach, to plot 2D surface contours of the detected signal, yields distinct target detectability and localization. The ability of the gen-2 imager to perform both reflectance and transillumination imaging allows its direct comparison to ultrasound and X-ray mammography results, respectively, in future clinical breast imaging studies.

Hand-Held Calculators in the Classroom: A Review of the Research.

ERIC Educational Resources Information Center

Parkhurst, Scott

This report surveys many of the recent investigations on calculators and their use in mathematics education. The review notes that the widespread availability of hand-held calculators and their affordability has led to their consideration as a viable tool to aid in mathematics instruction. The studies reviewed suggest that many questions are still…

Hand held lasers, a hazard to aircraft: How do we address this?

NASA Astrophysics Data System (ADS)

Barat, K.

2015-10-01

The availability of hand held lasers, commonly termed "laser pointers" is easy and wide spread, through commercial web sites and brick & mortar stores. The output of these hand held devices ranges from 1-5 milliWatts (mW) the legal laser pointer output limit, to 5000mW (5Watts). This is thousand times the maximum limit for pointers. Sadly the abuse of these devices is also wide spread. Over the last few years over 3000 aircraft are exposed to laser hits per year. While these aircraft exposures are of no danger to the aircraft frame but they can cause pilot distractions with the potential to cause a serve accident. The presentation will discuss the problem review visual effects, the regulatory response and how educators need to be aware of the problem and can take steps to educate students in the hope of having an effect.

Issues Arising on the Use of Hand-Held Calculators in Schools.

ERIC Educational Resources Information Center

D'Ambrosio, Ubiratan

This paper notes three objections to the use of hand-held calculators in schools: they would (1) block reasoning, (2) make individuals machine-dependent, and (3) broaden the gap between developed and underdeveloped nations. Each is addressed, with specific examples used to refute them. The belief is strongly expressed that calculators can aid in…

Abdominal aortic aneurysm screening program using hand-held ultrasound in primary healthcare

PubMed Central

Kostov, Belchin; Navarro González, Marta; Cararach Salami, Daniel; Pérez Jiménez, Alfonso; Gilabert Solé, Rosa; Bru Saumell, Concepció; Donoso Bach, Lluís; Villalta Martí, Mireia; González-de Paz, Luis; Ruiz Riera, Rafael; Riambau Alonso, Vicenç; Acar-Denizli, Nihan; Farré Almacellas, Marta; Ramos-Casals, Manuel; Benavent Àreu, Jaume

2017-01-01

We determined the feasibility of abdominal aortic aneurysm (AAA) screening program led by family physicians in public primary healthcare setting using hand-held ultrasound device. The potential study population was 11,214 men aged ≥ 60 years attended by three urban, public primary healthcare centers. Participants were recruited by randomly-selected telephone calls. Ultrasound examinations were performed by four trained family physicians with a hand-held ultrasound device (Vscan®). AAA observed were verified by confirmatory imaging using standard ultrasound or computed tomography. Cardiovascular risk factors were determined. The prevalence of AAA was computed as the sum of previously-known aneurysms, aneurysms detected by the screening program and model-based estimated undiagnosed aneurysms. We screened 1,010 men, with mean age of 71.3 (SD 6.9) years; 995 (98.5%) men had normal aortas and 15 (1.5%) had AAA on Vscan®. Eleven out of 14 AAA-cases (78.6%) had AAA on confirmatory imaging (one patient died). The total prevalence of AAA was 2.49% (95%CI 2.20 to 2.78). The median aortic diameter at diagnosis was 3.5 cm in screened patients and 4.7 cm (p<0.001) in patients in whom AAA was diagnosed incidentally. Multivariate logistic regression analysis identified coronary heart disease (OR = 4.6, 95%CI 1.3 to 15.9) as the independent factor with the highest odds ratio. A screening program led by trained family physicians using hand-held ultrasound was a feasible, safe and reliable tool for the early detection of AAA. PMID:28453577

Library service delivery via hand-held computers--the right information at the point of care.

PubMed

Peterson, Mary

2004-03-01

Today's health and medical librarians are well aware of the move towards evidence-based clinical practice which has emerged during the past decade. Hand-in-hand with this trend is the need for health practitioners to have access to the best possible evidence to help them in their clinical decision making. Libraries have a key role in the provision of information to their clients, and this means keeping abreast, not only of the various information sources available, but also the means by which those sources may be used. This paper will examine the effects that the hand-held computer is having on the work practices of our clients-library users. It is hoped that the paper will give an insight into the various types of library material which are suitable for use with hand-held devices, and an understanding of their advantages and limitations.

Hand-held spectrophotometer design for textile fabrics

NASA Astrophysics Data System (ADS)

Böcekçi, Veysel Gökhan; Yıldız, Kazım

2017-09-01

In this study, a hand-held spectrophotometer was designed by taking advantage of the developments in modern optoelectronic technology. Spectrophotometer devices are used to determine the color information from the optic properties of the materials. As an alternative to a desktop spectrophotometer device we have implemented, it is the first prototype, low cost and portable. The prototype model designed for the textile industry can detect the color tone of any fabric. The prototype model consists of optic sensor, processor, display floors. According to the color applied on the optic sensor, it produces special frequency information on its output at that color value. In Arduino type processor, the frequency information is evaluated by the program we have written and the color tone information between 0-255 ton is decided and displayed on the screen.

Cost effective spectral sensor solutions for hand held and field applications

NASA Astrophysics Data System (ADS)

Reetz, Edgar; Correns, Martin; Notni, Gunther

2015-05-01

Optical spectroscopy is without doubt one of the most important non-contact measurement principles. It is used in a wide range of applications from bio-medical to industrial fields. One recent trend is to miniaturize spectral sensors to address new areas of application. The most common spectral sensor type is based on diffraction gratings, while other types are based on micro mechanical systems (MEMS) or filter technologies. The authors represent the opinion that there is a potentially wide spread field of applications for spectrometers, but the market limits the range of applications since they cannot keep up with targeted cost requirements for consumer products. The present article explains an alternative approach for miniature multichannel spectrometer to enhance robustness for hand held field applications at a cost efficient price point.

Comparison of a digital and an optical analogue hand-held refractometer for the measurement of canine urine specific gravity.

PubMed

Paris, J K; Bennett, A D; Dodkin, S J; Gunn-Moore, D A

2012-05-05

Urine specific gravity (USG) is used clinically as a measure of urine concentration, and is routinely assessed by refractometry. A comparison between optical analogue and digital refractometers for evaluation of canine urine has not been reported. The aim of this study was to compare a digital and an optical analogue hand-held refractometer for the measurement of canine USG, and to assess correlation with urine osmolality. Prospective study. Free-catch urine samples were collected from 285 hospitalised adult dogs, and paired USG readings were obtained with a digital and an optical analogue refractometer. In 50 dogs, urine osmolality was also measured using a freezing point depression osmometer. There was a small but statistically significant difference between the two refractometers (P<0.001), with the optical analogue refractometer reading higher than the digital refractometer (mean difference 0.0006, sd 0.0012). Paired refractometer measurements varied by <0.002 in 91.5 per cent of cases. The optical analogue and digital refractometer readings showed excellent correlation with osmolality (r=0.980 and r=0.977, respectively, P<0.001 in both cases). Despite statistical significance, the difference between the two refractometers is unlikely to be clinically significant. Both instruments provide an accurate assessment of USG in dogs.

Hand-Held Devices Detect Explosives and Chemical Agents

NASA Technical Reports Server (NTRS)

2010-01-01

Ion Applications Inc., of West Palm Beach, Florida, partnered with Ames Research Center through Small Business Innovation Research (SBIR) agreements to develop a miniature version ion mobility spectrometer (IMS). While NASA was interested in the instrument for detecting chemicals during exploration of distant planets, moons, and comets, the company has incorporated the technology into a commercial hand-held IMS device for use by the military and other public safety organizations. Capable of detecting and identifying molecules with part-per-billion sensitivity, the technology now provides soldiers with portable explosives and chemical warfare agent detection. The device is also being adapted for detecting drugs and is employed in industrial processes such as semiconductor manufacturing.

Integrating a Hand Held computer and Stethoscope into a Fetal Monitor

PubMed Central

Ahmad Soltani, Mitra

2009-01-01

This article presents procedures for modifying a hand held computer or personal digital assistant (PDA) into a versatile device functioning as an electronic stethoscope for fetal monitoring. Along with functioning as an electronic stethoscope, a PDA can provide a useful information source for a medical trainee. Feedback from medical students, residents and interns suggests the device is well accepted by medical trainees. PMID:20165517

Hand-Held Electronic Gap-Measuring Tools

NASA Technical Reports Server (NTRS)

Sugg, F. E.; Thompson, F. W.; Aragon, L. A.; Harrington, D. B.

1985-01-01

Repetitive measurements simplified by tool based on LVDT operation. With fingers in open position, Gap-measuring tool rests on digital readout instrument. With fingers inserted in gap, separation alters inductance of linear variable-differential transformer in plastic handle. Originally developed for measuring gaps between surface tiles of Space Shuttle orbiter, tool reduces measurement time from 20 minutes per tile to 2 minutes. Also reduces possibility of damage to tiles during measurement. Tool has potential applications in mass production; helps ensure proper gap dimensions in assembly of refrigerator and car doors and also used to measure dimensions of components and to verify positional accuracy of components during progressive assembly operations.

Simultaneous hand-held contact color fundus and SD-OCT imaging for pediatric retinal diseases (Conference Presentation)

NASA Astrophysics Data System (ADS)

Ruggeri, Marco; Hernandez, Victor; De Freitas, Carolina; Relhan, Nidhi; Silgado, Juan; Manns, Fabrice; Parel, Jean-Marie

2016-03-01

Hand-held wide-field contact color fundus photography is currently the standard method to acquire diagnostic images of children during examination under anesthesia and in the neonatal intensive care unit. The recent development of portable non-contact hand-held OCT retinal imaging systems has proved that OCT is of tremendous help to complement fundus photography in the management of pediatric patients. Currently, there is no commercial or research system that combines color wide-field digital fundus and OCT imaging in a contact-fashion. The contact of the probe with the cornea has the advantages of reducing motion experienced by the photographer during the imaging and providing fundus and OCT images with wider field of view that includes the periphery of the retina. In this study we produce proof of concept for a contact-type hand-held unit for simultaneous color fundus and OCT live view of the retina of pediatric patients. The front piece of the hand-held unit consists of a contact ophthalmoscopy lens integrating a circular light guide that was recovered from a digital fundus camera for pediatric imaging. The custom-made rear piece consists of the optics to: 1) fold the visible aerial image of the fundus generated by the ophthalmoscopy lens on a miniaturized level board digital color camera; 2) conjugate the eye pupil to the galvanometric scanning mirrors of an OCT delivery system. Wide-field color fundus and OCT images were simultaneously obtained in an eye model and sequentially obtained on the eye of a conscious 25 year-old human subject with healthy retina.

Hand-Held Self-Maneuvering Unit to be used during EVA on Gemini 4

NASA Image and Video Library

1965-06-02

Hand-Held Self-Maneuvering Unit to be used during extravehicular activity (EVA) on Gemini 4 flight. It is an integral unit that contains its own high pressure metering valves and nozzles required to produce controlled thrust. A camera is mounted on the front of the unit.

Defining Uncertainty and Error in Planktic Foraminiferal Oxygen Isotope Measurements

NASA Astrophysics Data System (ADS)

Fraass, A. J.; Lowery, C.

2016-12-01

Foraminifera are the backbone of paleoceanography, and planktic foraminifera are one of the leading tools for reconstructing water column structure. Currently, there are unconstrained variables when dealing with the reproducibility of oxygen isotope measurements. This study presents the first results from a simple model of foraminiferal calcification (Foraminiferal Isotope Reproducibility Model; FIRM), designed to estimate the precision and accuracy of oxygen isotope measurements. FIRM produces synthetic isotope data using parameters including location, depth habitat, season, number of individuals included in measurement, diagenesis, misidentification, size variation, and vital effects. Reproducibility is then tested using Monte Carlo simulations. The results from a series of experiments show that reproducibility is largely controlled by the number of individuals in each measurement, but also strongly a function of local oceanography if the number of individuals is held constant. Parameters like diagenesis or misidentification have an impact on both the precision and the accuracy of the data. Currently FIRM is a tool to estimate isotopic error values best employed in the Holocene. It is also a tool to explore the impact of myriad factors on the fidelity of paleoceanographic records. FIRM was constructed in the open-source computing environment R and is freely available via GitHub. We invite modification and expansion, and have planned inclusions for benthic foram reproducibility and stratigraphic uncertainty.

An Examination of Hand-Held Computer-Assisted Instruction on Subtraction Skills for Second Grade Students with Learning and Behavioral Disabilities

ERIC Educational Resources Information Center

Nordness, Philip D.; Haverkost, Ann; Volberding, Annette

2011-01-01

The effect of a mathematic flashcard application on a hand-held computing device was examined across three individual second grade students with learning and behavioral disabilities. All of the students improved their subtraction scores by an average of 17% as measured by the district-created, curriculum-based assessment. The results of this study…

Neurosurgical hand-held optical coherence tomography (OCT) forward-viewing probe

NASA Astrophysics Data System (ADS)

Sun, Cuiru; Lee, Kenneth K. C.; Vuong, Barry; Cusimano, Michael; Brukson, Alexander; Mariampillai, Adrian; Standish, Beau A.; Yang, Victor X. D.

2012-02-01

A prototype neurosurgical hand-held optical coherence tomography (OCT) imaging probe has been developed to provide micron resolution cross-sectional images of subsurface tissue during open surgery. This new ergonomic hand-held probe has been designed based on our group's previous work on electrostatically driven optical fibers. It has been packaged into a catheter probe in the familiar form factor of the clinically accepted Bayonet shaped neurosurgical non-imaging Doppler ultrasound probes. The optical design was optimized using ZEMAX simulation. Optical properties of the probe were tested to yield an ~20 um spot size, 5 mm working distance and a 3.5 mm field of view. The scan frequency can be increased or decreased by changing the applied voltage. Typically a scan frequency of less than 60Hz is chosen to keep the applied voltage to less than 2000V. The axial resolution of the probe was ~15 um (in air) as determined by the OCT system. A custom-triggering methodology has been developed to provide continuous stable imaging, which is crucial for clinical utility. Feasibility of this probe, in combination with a 1310 nm swept source OCT system was tested and images are presented to highlight the usefulness of such a forward viewing handheld OCT imaging probe. Knowledge gained from this research will lay the foundation for developing new OCT technologies for endovascular management of cerebral aneurysms and transsphenoidal neuroendoscopic treatment of pituitary tumors.

75 FR 27504 - Substantial Product Hazard List: Hand-Held Hair Dryers

Federal Register 2010, 2011, 2012, 2013, 2014

2010-05-17

...The Consumer Product Safety Improvement Act of 2008 (``CPSIA''), authorizes the United States Consumer Product Safety Commission (``Commission'') to specify, by rule, for any consumer product or class of consumer products, characteristics whose existence or absence shall be deemed a substantial product hazard under certain circumstances. In this document, the Commission is proposing a rule to determine that any hand-held hair dryer without integral immersion protection presents a substantial product hazard.

DataPlus™ - a revolutionary applications generator for DOS hand-held computers

Treesearch

David Dean; Linda Dean

2000-01-01

DataPlus allows the user to easily design data collection templates for DOS-based hand-held computers that mimic clipboard data sheets. The user designs and tests the application on the desktop PC and then transfers it to a DOS field computer. Other features include: error checking, missing data checks, and sensor input from RS-232 devices such as bar code wands,...

Driver hand-held mobile phone use and safety belt use.

PubMed

Eby, David W; Vivoda, Jonathon M

2003-11-01

The purposes of the study were to identify hand-held mobile phone use trends for Michigan and to compare safety belt use between users and nonusers. Mobile phone and safety belt use was investigated by a direct observation survey of drivers at intersections in Michigan. Data were weighted to calculate mobile phone use and safety belt use rates statewide. The study showed 2.7% of Michigan drivers were using a mobile phone at any given daylight time. Safety belt use of current mobile phone users was significantly lower than those not using mobile phones.

An efficient solid modeling system based on a hand-held 3D laser scan device

NASA Astrophysics Data System (ADS)

Xiong, Hanwei; Xu, Jun; Xu, Chenxi; Pan, Ming

2014-12-01

The hand-held 3D laser scanner sold in the market is appealing for its port and convenient to use, but price is expensive. To develop such a system based cheap devices using the same principles as the commercial systems is impossible. In this paper, a simple hand-held 3D laser scanner is developed based on a volume reconstruction method using cheap devices. Unlike convenient laser scanner to collect point cloud of an object surface, the proposed method only scan few key profile curves on the surface. Planar section curve network can be generated from these profile curves to construct a volume model of the object. The details of design are presented, and illustrated by the example of a complex shaped object.

Inter-Tester Reliability and Precision of Manual Muscle Testing and Hand-Held Dynamometry in Lower Limb Muscles of Children with Spina Bifida

ERIC Educational Resources Information Center

Mahony, Kate; Hunt, Adrienne; Daley, Deborah; Sims, Susan; Adams, Roger

2009-01-01

Reliability and measurement precision of manual muscle testing (MMT) and hand-held dynamometry (HHD) were compared for children with spina bifida. Strength measures were obtained of the hip flexors, hip abductors, and knee extensors of 20 children (10 males, 10 females; mean age 9 years 10 months; range: 5 to 15 years) by two experienced physical…

Survey reveals public open to ban on hand-held cell phone use and texting.

DOT National Transportation Integrated Search

2013-01-01

A study performed by the Bureau of Transportation Statistics : (BTS) reveals that the public is open to a ban on : hand-held cell phone use while driving. The study is based : on data from 2009s Omnibus Household Survey (OHS), : which is administe...

Direction-Sensitive Hand-Held Gamma-Ray Spectrometer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mukhopadhyay, S.

2012-10-04

A novel, light-weight, hand-held gamma-ray detector with directional sensitivity is being designed. The detector uses a set of multiple rings around two cylindrical surfaces, which provides precise location of two interaction points on two concentric cylindrical planes, wherefrom the source location can be traced back by back projection and/or Compton imaging technique. The detectors are 2.0 × 2.0 mm europium-doped strontium iodide (SrI2:Eu2+) crystals, whose light output has been measured to exceed 120,000 photons/MeV, making it one of the brightest scintillators in existence. The crystal’s energy resolution, less than 3% at 662 keV, is also excellent, and the response ismore » highly linear over a wide range of gamma-ray energies. The emission of SrI2:Eu2+ is well matched to both photo-multiplier tubes and blue-enhanced silicon photodiodes. The solid-state photomultipliers used in this design (each 2.0 × 2.0 mm) are arrays of active pixel sensors (avalanche photodiodes driven beyond their breakdown voltage in reverse bias); each pixel acts as a binary photon detector, and their summed output is an analog representation of the total photon energy, while the individual pixel accurately defines the point of interaction. A simple back-projection algorithm involving cone-surface mapping is being modeled. The back projection for an event cone is a conical surface defining the possible location of the source. The cone axis is the straight line passing through the first and second interaction points.« less

Diolistic labeling of neuronal cultures and intact tissue using a hand-held gene gun

PubMed Central

O'Brien, John A; Lummis, Sarah CR

2009-01-01

Diolistic labeling is a highly efficient method for introducing dyes into cells using biolistic techniques. The use of lipophilic carbocyanine dyes, combined with particle-mediated biolistic delivery using a hand-held gene gun, allows non-toxic labeling of multiple cells in both living and fixed tissue. The technique is rapid (labeled cells can be visualized in minutes) and technically undemanding. Here, we provide a detailed protocol for diolistic labeling of cultured human embryonic kidney 293 cells and whole brain using a hand-held gene gun. There are four major steps: (i) coating gold microcarriers with one or more dyes; (ii) transferring the microcarriers into a cartridge to make a bullet; (iii) preparation of cells or intact tissue; and (iv) firing the microcarriers into cells or tissue. The method can be readily adapted to other cell types and tissues. This protocol can be completed in less than 1 h. PMID:17406443

Applying Hand-Held 3D Printing Technology to the Teaching of VSEPR Theory

ERIC Educational Resources Information Center

Dean, Natalie L.; Ewan, Corrina; McIndoe, J. Scott

2016-01-01

The use of hand-held 3D printing technology provides a unique and engaging approach to learning VSEPR theory by enabling students to draw three-dimensional depictions of different molecular geometries, giving them an appreciation of the shapes of the building blocks of complex molecular structures. Students are provided with 3D printing pens and…

Smartphone based hand-held quantitative phase microscope using the transport of intensity equation method.

PubMed

Meng, Xin; Huang, Huachuan; Yan, Keding; Tian, Xiaolin; Yu, Wei; Cui, Haoyang; Kong, Yan; Xue, Liang; Liu, Cheng; Wang, Shouyu

2016-12-20

In order to realize high contrast imaging with portable devices for potential mobile healthcare, we demonstrate a hand-held smartphone based quantitative phase microscope using the transport of intensity equation method. With a cost-effective illumination source and compact microscope system, multi-focal images of samples can be captured by the smartphone's camera via manual focusing. Phase retrieval is performed using a self-developed Android application, which calculates sample phases from multi-plane intensities via solving the Poisson equation. We test the portable microscope using a random phase plate with known phases, and to further demonstrate its performance, a red blood cell smear, a Pap smear and monocot root and broad bean epidermis sections are also successfully imaged. Considering its advantages as an accurate, high-contrast, cost-effective and field-portable device, the smartphone based hand-held quantitative phase microscope is a promising tool which can be adopted in the future in remote healthcare and medical diagnosis.

Spray distribution evaluation of different settings of a hand-held-trolley sprayer used in greenhouse tomato crops.

PubMed

Llop, Jordi; Gil, Emilio; Gallart, Montserrat; Contador, Felipe; Ercilla, Mireia

2016-03-01

Hand-held-trolley sprayers have recently been promoted to improve spray application techniques in greenhouses in south-eastern Spain. However, certain aspects remain to be improved. A modified hand-held-trolley sprayer was evaluated under two different canopy conditions (high and low canopy density) and with several sprayer settings (nozzle type, air assistance and spray volume). In this study, the deposition, coverage and uniformity of distribution of the spray on the canopy have been assessed. The deposition on leaves was significantly higher when flat-fan nozzles and air assistance were used at both high and low spray volumes. No differences were detected between the reference system at a high spray volume and the modified trolley at a low spray volume. Flat-fan nozzles with air assistance increased penetrability into the canopy. Air assistance and flat-fan nozzles allow volume rates to be reduced while maintaining or improving spray quality distribution. The working parameters of hand-held sprayers must be considered to reduce environmental risk and increase the efficacy of the spraying process. © 2015 Society of Chemical Industry. © 2015 Society of Chemical Industry.

Hand-held Raman sensor head for in-situ characterization of meat quality applying a microsystem 671 nm diode laser

NASA Astrophysics Data System (ADS)

Schmidt, Heinar; Sowoidnich, Kay; Maiwald, Martin; Sumpf, Bernd; Kronfeldt, Heinz-Detlef

2009-05-01

A hand-held Raman sensor head was developed for the in-situ characterization of meat quality. As light source, a microsystem based external cavity diode laser module (ECDL) emitting at 671 nm was integrated in the sensor head and attached to a miniaturized optical bench which contains lens optics for excitation and signal collection as well as a Raman filter stage for Rayleigh rejection. The signal is transported with an optical fiber to the detection unit which was in the initial phase a laboratory spectrometer with CCD detector. All elements of the ECDL are aligned on a micro optical bench with 13 x 4 mm2 footprint. The wavelength stability is provided by a reflection Bragg grating and the laser has an optical power of up to 200 mW. However, for the Raman measurements of meat only 35 mW are needed to obtain Raman spectra within 1 - 5 seconds. Short measuring times are essential for the hand-held device. The laser and the sensor head are characterized in terms of stability and performance for in-situ Raman investigations. The function is demonstrated in a series of measurements with raw and packaged pork meat as samples. The suitability of the Raman sensor head for the quality control of meat and other products will be discussed.

Motion-compensated hand-held common-path Fourier-domain optical coherence tomography probe for image-guided intervention

NASA Astrophysics Data System (ADS)

Huang, Yong; Song, Cheol; Liu, Xuan; Kang, Jin U.

2013-03-01

A motion-compensated hand-held common-path Fourier-domain optical coherence tomography imaging probe has been developed for image guided intervention during microsurgery. A hand-held prototype instrument was designed and fabricated by integrating an imaging fiber probe inside a stainless steel needle which is attached to the ceramic shaft of a piezoelectric motor housed in an aluminum handle. The fiber probe obtains A-scan images. The distance information was extracted from the A-scans to track the sample surface distance and a fixed distance was maintained by a feedback motor control which effectively compensated hand tremor and target movements in the axial direction. Graphical user interface, real-time data processing, and visualization based on a CPU-GPU hybrid programming architecture were developed and used in the implantation of this system. To validate the system, free-hand optical coherence tomography images using various samples were obtained. The system can be easily integrated into microsurgical tools and robotics for a wide range of clinical applications. Such tools could offer physicians the freedom to easily image sites of interest with reduced risk and higher image quality.

Into the Wild: Neuroergonomic Differentiation of Hand-Held and Augmented Reality Wearable Displays during Outdoor Navigation with Functional Near Infrared Spectroscopy.

PubMed

McKendrick, Ryan; Parasuraman, Raja; Murtza, Rabia; Formwalt, Alice; Baccus, Wendy; Paczynski, Martin; Ayaz, Hasan

2016-01-01

Highly mobile computing devices promise to improve quality of life, productivity, and performance. Increased situation awareness and reduced mental workload are two potential means by which this can be accomplished. However, it is difficult to measure these concepts in the "wild". We employed ultra-portable battery operated and wireless functional near infrared spectroscopy (fNIRS) to non-invasively measure hemodynamic changes in the brain's Prefrontal cortex (PFC). Measurements were taken during navigation of a college campus with either a hand-held display, or an Augmented reality wearable display (ARWD). Hemodynamic measures were also paired with secondary tasks of visual perception and auditory working memory to provide behavioral assessment of situation awareness and mental workload. Navigating with an augmented reality wearable display produced the least workload during the auditory working memory task, and a trend for improved situation awareness in our measures of prefrontal hemodynamics. The hemodynamics associated with errors were also different between the two devices. Errors with an augmented reality wearable display were associated with increased prefrontal activity and the opposite was observed for the hand-held display. This suggests that the cognitive mechanisms underlying errors between the two devices differ. These findings show fNIRS is a valuable tool for assessing new technology in ecologically valid settings and that ARWDs offer benefits with regards to mental workload while navigating, and potentially superior situation awareness with improved display design.

A high resolution hand-held focused beam profiler

NASA Astrophysics Data System (ADS)

Zapata-Farfan, J.; Garduño-Mejía, J.; Rosete-Aguilar, M.; Ascanio, G.; Román-Moreno, C. J.

2017-05-01

The shape of a beam is important in any laser application and depending on the final implementation, there exists a preferred one which is defined by the irradiance distribution.1 The energy distribution (or laser beam profile) is an important parameter in a focused beam, for instance, in laser cut industry, where the beam shape determines the quality of the cut. In terms of alignment and focusing, the energy distribution also plays an important role since the system must be configured in order to reduce the aberration effects and achieve the highest intensity. Nowadays a beam profiler is used in both industry and research laboratories with the aim to characterize laser beams used in free-space communications, focusing and welding, among other systems. The purpose of the profile analyzers is to know the main parameters of the beam, to control its characteristics as uniformity, shape and beam size as a guide to align the focusing system. In this work is presented a high resolution hand-held and compact design of a beam profiler capable to measure at the focal plane, with covered range from 400 nm to 1000 nm. The detection is reached with a CMOS sensor sized in 3673.6 μm x 2738.4 μm which acquire a snap shot of the previously attenuated focused beam to avoid the sensor damage, the result is an image of beam intensity distribution, which is digitally processed with a RaspberryTMmodule gathering significant parameters such as beam waist, centroid, uniformity and also some aberrations. The profiler resolution is 1.4 μm and was probed and validated in three different focusing systems. The spot sizes measurements were compared with the Foucault knife-edge test.

78 FR 20695 - Walk-Through Metal Detectors and Hand-Held Metal Detectors Test Method Validation

Federal Register 2010, 2011, 2012, 2013, 2014

2013-04-05

... Detectors and Hand-Held Metal Detectors Test Method Validation AGENCY: National Institute of Justice, DOJ... ensure that the test methods in the standards are properly documented, NIJ is requesting proposals (including price quotes) for test method validation efforts from testing laboratories. NIJ is also seeking...

77 FR 40637 - Honeywell International, Scanning and Mobility Division, Formerly Known as Hand Held Products...

Federal Register 2010, 2011, 2012, 2013, 2014

2012-07-10

..., Scanning and Mobility Division, Formerly Known as Hand Held Products, Inc., Including On-Site Leased Workers From Manpower, Skaneatelles Falls, NY; Amended Certification Regarding Eligibility To Apply for...''), 19 U.S.C. 2273, the Department of Labor issued a Certification of Eligibility to Apply for Worker...

Applications of a hand-held GPS receiver in South American rain forests

NASA Technical Reports Server (NTRS)

Baksh, Michael

1991-01-01

A hand-held Global Positioning System receiver was used to determine the precise locations of villages, houses, gardens, and other cultural and environmental features in poorly mapped South American rain forests. The Magellan NAV 1000 unit profides extremely accurate latitude and longitude information, but determination of altitude is problematical. Overall, the receiver effectively allows anthropologists to obtain essential locational data useful for categorizing land uses, mapping tribal boundaries, and other applications in regions where environmental conditions are harsh and/or accessibility is difficult.

Rapid Diagnosis of an Ulnar Fracture with Portable Hand-Held Ultrasound

NASA Technical Reports Server (NTRS)

Kirkpatrick, Andrew W.; Brown, Ross; Diebel, Lawrence N.; Nicolaou, Savvas; Marshburn, Tom; Dulchavsky, Scott A.

2002-01-01

Orthopedic fractures are a common injury in operational activities, injuries that often occur in isolated or hostile environments. Clinical ultrasound devices have become more user friendly and lighter allowing them to be easily transported with forward medical teams. The bone-soft tissue interface has a very large acoustic impedance, with a high reflectance that can be used to visualize breaks in contour including fractures. Herein reported is a case of an ulnar fracture that was quickly visualized in the early phase of a multi-system trauma resuscitation with a hand-held ultrasound device. The implications for operational medicine are discussed.

Rapid and automatic chemical identification of the medicinal flower buds of Lonicera plants by the benchtop and hand-held Fourier transform infrared spectroscopy

NASA Astrophysics Data System (ADS)

Chen, Jianbo; Guo, Baolin; Yan, Rui; Sun, Suqin; Zhou, Qun

2017-07-01

With the utilization of the hand-held equipment, Fourier transform infrared (FT-IR) spectroscopy is a promising analytical technique to minimize the time cost for the chemical identification of herbal materials. This research examines the feasibility of the hand-held FT-IR spectrometer for the on-site testing of herbal materials, using Lonicerae Japonicae Flos (LJF) and Lonicerae Flos (LF) as examples. Correlation-based linear discriminant models for LJF and LF are established based on the benchtop and hand-held FT-IR instruments. The benchtop FT-IR models can exactly recognize all articles of LJF and LF. Although a few LF articles are misjudged at the sub-class level, the hand-held FT-IR models are able to exactly discriminate LJF and LF. As a direct and label-free analytical technique, FT-IR spectroscopy has great potential in the rapid and automatic chemical identification of herbal materials either in laboratories or in fields. This is helpful to prevent the spread and use of adulterated herbal materials in time.

Prevalence of Hand-transmitted Vibration Exposure among Grass-cutting Workers using Objective and Subjective Measures

NASA Astrophysics Data System (ADS)

Azmir, N. A.; Yahya, M. N.

2017-01-01

Extended exposure to hand-transmitted vibration from vibrating machine is associated with an increased occurrence of symptoms of occupational disease related to hand disorder. The present case study is to determine the prevalence and correlation of significant subjective as well as objective variables that induce to hand arm vibration syndrome (HAVS) among hand-held grass-cutting workers in Malaysia. Thus, recommendations are made for grass-cutting workers and grass maintenance service management based on findings. A cross sectional study using adopted subjective Hand Arm Vibration Exposure Risk Assessment (HAVERA) questionnaire from Vibration Injury Network on hand disorder signs and symptoms was distributed to a sample of one hundred and sixty eight male workers from grass and turf maintenance industry that use vibrating machine as part of their work. For objective measure, hand-transmitted vibration measurement was collected on site during operation by the following ISO 5349-1, 2001. Two groups were identified in this research comprising of high exposure group and low-moderate exposure group. Workers also gave information about their personal identification, social history, workers’ health, occupational history and machine safety inspection. There was positive HAVS symptoms relationship between the low-moderate exposure group and high exposure group among hand-held grass-cutting workers. The prevalence ratio (PR) was considered high for experiencing white colour change at fingers and fingers go numb which are 3.63 (1.41 to 9.39) and 4.24 (2.18 to 8.27), respectively. The estimated daily vibration exposure, A(8) differs between 2.1 to 20.7 ms-2 for right hand while 2.7 to 29.1 ms-2 for left hand. The subjects claimed that the feel of numbness at left hand is much stronger compared to right hand. The results suggest that HAVS is diagnosed in Malaysia especially in agriculture sector. The A(8) indicates that the exposure value is more than exposure limit value

Drift from the Use of Hand-Held Knapsack Pesticide Sprayers in Boyacá (Colombian Andes).

PubMed

García-Santos, Glenda; Feola, Giuseppe; Nuyttens, David; Diaz, Jaime

2016-05-25

Offsite pesticide losses in tropical mountainous regions have been little studied. One example is measuring pesticide drift soil deposition, which can support pesticide risk assessment for surface water, soil, bystanders, and off-target plants and fauna. This is considered a serious gap, given the evidence of pesticide-related poisoning in those regions. Empirical data of drift deposition of a pesticide surrogate, Uranine tracer, within one of the highest potato-producing regions in Colombia, characterized by small plots and mountain orography, is presented. High drift values encountered in this study reflect the actual spray conditions using hand-held knapsack sprayers. Comparison between measured and predicted drift values using three existing empirical equations showed important underestimation. However, after their optimization based on measured drift information, the equations showed a strong predictive power for this study area and the study conditions. The most suitable curve to assess mean relative drift was the IMAG calculator after optimization.

Into the Wild: Neuroergonomic Differentiation of Hand-Held and Augmented Reality Wearable Displays during Outdoor Navigation with Functional Near Infrared Spectroscopy

PubMed Central

McKendrick, Ryan; Parasuraman, Raja; Murtza, Rabia; Formwalt, Alice; Baccus, Wendy; Paczynski, Martin; Ayaz, Hasan

2016-01-01

Highly mobile computing devices promise to improve quality of life, productivity, and performance. Increased situation awareness and reduced mental workload are two potential means by which this can be accomplished. However, it is difficult to measure these concepts in the “wild”. We employed ultra-portable battery operated and wireless functional near infrared spectroscopy (fNIRS) to non-invasively measure hemodynamic changes in the brain’s Prefrontal cortex (PFC). Measurements were taken during navigation of a college campus with either a hand-held display, or an Augmented reality wearable display (ARWD). Hemodynamic measures were also paired with secondary tasks of visual perception and auditory working memory to provide behavioral assessment of situation awareness and mental workload. Navigating with an augmented reality wearable display produced the least workload during the auditory working memory task, and a trend for improved situation awareness in our measures of prefrontal hemodynamics. The hemodynamics associated with errors were also different between the two devices. Errors with an augmented reality wearable display were associated with increased prefrontal activity and the opposite was observed for the hand-held display. This suggests that the cognitive mechanisms underlying errors between the two devices differ. These findings show fNIRS is a valuable tool for assessing new technology in ecologically valid settings and that ARWDs offer benefits with regards to mental workload while navigating, and potentially superior situation awareness with improved display design. PMID:27242480

Finger tracking for hand-held device interface using profile-matching stereo vision

NASA Astrophysics Data System (ADS)

Chang, Yung-Ping; Lee, Dah-Jye; Moore, Jason; Desai, Alok; Tippetts, Beau

2013-01-01

Hundreds of millions of people use hand-held devices frequently and control them by touching the screen with their fingers. If this method of operation is being used by people who are driving, the probability of deaths and accidents occurring substantially increases. With a non-contact control interface, people do not need to touch the screen. As a result, people will not need to pay as much attention to their phones and thus drive more safely than they would otherwise. This interface can be achieved with real-time stereovision. A novel Intensity Profile Shape-Matching Algorithm is able to obtain 3-D information from a pair of stereo images in real time. While this algorithm does have a trade-off between accuracy and processing speed, the result of this algorithm proves the accuracy is sufficient for the practical use of recognizing human poses and finger movement tracking. By choosing an interval of disparity, an object at a certain distance range can be segmented. In other words, we detect the object by its distance to the cameras. The advantage of this profile shape-matching algorithm is that detection of correspondences relies on the shape of profile and not on intensity values, which are subjected to lighting variations. Based on the resulting 3-D information, the movement of fingers in space from a specific distance can be determined. Finger location and movement can then be analyzed for non-contact control of hand-held devices.

Multi-Sensor Systems Development for UXO Detection and Discrimination: Hand-Held Dual Magnetic/Electromagnetic Induction Sensor

DTIC Science & Technology

2008-04-01

5 Fluxgate magnetometer ... magnetometer into digital format, and transmitted as a single serial data string to log the Cs and fluxgate magnetometer data. After procurement...Hardware The system hardware comprises an EMI sensor, Cs vapor magnetometer , fluxgate magnetometer , hand-held data acquisition computer, integrated

Occupational risk identification using hand-held or laptop computers.

PubMed

Naumanen, Paula; Savolainen, Heikki; Liesivuori, Jyrki

2008-01-01

This paper describes the Work Environment Profile (WEP) program and its use in risk identification by computer. It is installed into a hand-held computer or a laptop to be used in risk identification during work site visits. A 5-category system is used to describe the identified risks in 7 groups, i.e., accidents, biological and physical hazards, ergonomic and psychosocial load, chemicals, and information technology hazards. Each group contains several qualifying factors. These 5 categories are colour-coded at this stage to aid with visualization. Risk identification produces visual summary images the interpretation of which is facilitated by colours. The WEP program is a tool for risk assessment which is easy to learn and to use both by experts and nonprofessionals. It is especially well adapted to be used both in small and in larger enterprises. Considerable time is saved as no paper notes are needed.

Hand-Held Model of a Sarcomere to Illustrate the Sliding Filament Mechanism in Muscle Contraction

ERIC Educational Resources Information Center

Jittivadhna, Karnyupha; Ruenwongsa, Pintip; Panijpan, Bhinyo

2009-01-01

From our teaching of the contractile unit of the striated muscle, we have found limitations in using textbook illustrations of sarcomere structure and its related dynamic molecular physiological details. A hand-held model of a striated muscle sarcomere made from common items has thus been made by us to enhance students' understanding of the…

Hand-Held Color Meters Based on Interference Filters

NASA Technical Reports Server (NTRS)

Snyder, G. Jeffrey; Fleurial, Jean-Pierre; Caillat, Thierry; Chen, Gang; Yang, Rong Gui

2004-01-01

Small, inexpensive, hand-held optoelectronic color-measuring devices based on metal-film/dielectric-film interference filters are undergoing development. These color meters could be suitable for use in a variety of applications in which there are requirements to quantify or match colors for aesthetic purposes but there is no need for the high spectral resolution of scientific-grade spectrometers. Such applications typically occur in the paint, printing, and cosmetic industries, for example. The figure schematically depicts a color meter of this type being used to measure the color of a sample in terms of the spectrum of light reflected from the sample. Light from a white source (for example, a white light-emitting diode) passes through a collimating lens to the sample. Another lens collects some of the light reflected from the sample and focuses the light onto the input end of optical fiber. Light emerging from the output end of the optical fiber illuminates an array of photodetectors covered with metal/dielectric-film interference filters like those described in Metal/Dielectric-film Interference Color Filters (NPO-20217), NASA Tech Briefs, Vol. 23, No. 2 (February 1999), page 70. Typically, these are wide-band-pass filters, as shown at the bottom of the figure. The photodetector array need not be of any particular design: it could be something as simple as an assembly containing several photodiodes or something as elaborate as an active-pixel sensor or other imaging device. What is essential is that each of the photodetectors or each of several groups of photodetectors is covered with a metal/dielectric-film filter of a different color. In most applications, it would be desirable to have at least three different filters, each for a spectral band that contains one of the three primary additive red, green, and blue colors. In some applications, it may be necessary to have more than three different color filters in order to characterize subtle differences in color

Reliability and Validity of Isometric Knee Extensor Strength Test With Hand-Held Dynamometer Depending on Its Fixation: A Pilot Study

PubMed Central

Kim, Won Kuel; Seo, Kyung Mook; Kang, Si Hyun

2014-01-01

Objective To determine the reliability and validity of hand-held dynamometer (HHD) depending on its fixation in measuring isometric knee extensor strength by comparing the results with an isokinetic dynamometer. Methods Twenty-seven healthy female volunteers participated in this study. The subjects were tested in seated and supine position using three measurement methods: isometric knee extension by isokinetic dynamometer, non-fixed HHD, and fixed HHD. During the measurement, the knee joints of subjects were fixed at a 35° angle from the extended position. The fixed HHD measurement was conducted with the HHD fixed to distal tibia with a Velcro strap; non-fixed HHD was performed with a hand-held method without Velcro fixation. All the measurements were repeated three times and among them, the maximum values of peak torque were used for the analysis. Results The data from the fixed HHD method showed higher validity than the non-fixed method compared with the results of the isokinetic dynamometer. Pearson correlation coefficients (r) between fixed HHD and isokinetic dynamometer method were statistically significant (supine-right: r=0.806, p<0.05; seating-right: r=0.473, p<0.05; supine-left: r=0.524, p<0.05), whereas Pearson correlation coefficients between non-fixed dynamometer and isokinetic dynamometer methods were not statistically significant, except for the result of the supine position of the left leg (r=0.384, p<0.05). Both fixed and non-fixed HHD methods showed excellent inter-rater reliability. However, the fixed HHD method showed a higher reliability than the non-fixed HHD method by considering the intraclass correlation coefficient (fixed HHD, 0.952-0.984; non-fixed HHD, 0.940-0.963). Conclusion Fixation of HHD during measurement in the supine position increases the reliability and validity in measuring the quadriceps strength. PMID:24639931

Assessment of foot and ankle muscle strength using hand held dynamometry in patients with established rheumatoid arthritis.

PubMed

Carroll, Matthew; Joyce, William; Brenton-Rule, Angela; Dalbeth, Nicola; Rome, Keith

2013-03-22

The foot and ankle are frequently affected in patients with rheumatoid arthritis (RA). One of the negative consequences of RA on the physical function of patients is a decrease in muscle strength. However, little is known about foot and muscle strength in this population. The aim of the study was to evaluate significant differences in foot and ankle muscle strength between patients with established RA against age and sex-matched controls using hand-held dynamometry. The maximal muscle strength of ankle plantarflexion, dorsiflexion, eversion and inversion was assessed in 14 patients with RA, mean (SD) disease duration of 22 (14.1) years, and 20 age and sex-matched control participants using hand-held dynamometry. Significant differences were observed in muscle strength between the two groups in plantarflexion (p = 0.00), eversion (p = 0.04) and inversion (p = 0.01). No significant difference was found in dorsiflexion (p > 0.05). The patients with RA displayed a significantly lower plantarflexion-dorsiflexion ratio than the control participants (p = 0.03). The results from this study showed that the RA patients displayed a significant decrease in ankle dorsiflexion, eversion and inversion when compared to the non-RA control group suggesting that foot and ankle muscle strength may be affected by the pathological processes in RA. This study is a preliminary step for the measurement of muscle impairments within the RA population.

Assessment of foot and ankle muscle strength using hand held dynamometry in patients with established rheumatoid arthritis

PubMed Central

2013-01-01

Background The foot and ankle are frequently affected in patients with rheumatoid arthritis (RA). One of the negative consequences of RA on the physical function of patients is a decrease in muscle strength. However, little is known about foot and muscle strength in this population. The aim of the study was to evaluate significant differences in foot and ankle muscle strength between patients with established RA against age and sex-matched controls using hand-held dynamometry. Methods The maximal muscle strength of ankle plantarflexion, dorsiflexion, eversion and inversion was assessed in 14 patients with RA, mean (SD) disease duration of 22 (14.1) years, and 20 age and sex-matched control participants using hand-held dynamometry. Results Significant differences were observed in muscle strength between the two groups in plantarflexion (p = 0.00), eversion (p = 0.04) and inversion (p = 0.01). No significant difference was found in dorsiflexion (p > 0.05). The patients with RA displayed a significantly lower plantarflexion-dorsiflexion ratio than the control participants (p = 0.03). Conclusions The results from this study showed that the RA patients displayed a significant decrease in ankle dorsiflexion, eversion and inversion when compared to the non-RA control group suggesting that foot and ankle muscle strength may be affected by the pathological processes in RA. This study is a preliminary step for the measurement of muscle impairments within the RA population. PMID:23522448

US-ROK Action Sheet 34: Safeguards Application of a Hand-held Mechanically Cooled Germanium Spectrometer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dreyer, J.; Burks, M.; Ham, Y.

2015-10-20

This report summarizes results of Action Sheet 34 - for the cooperative efforts on the field testing and evaluation of a high-resolution, hand-held, gamma-ray spectrometer, known as SPG (Spectroscopic Planar Germanium), for safeguards application such as short notice inspections, UF6 analysis, enrichment determination, and other potential applications. The Spectroscopic Planar Germanium (SPG) has been demonstrated IAEA Physical Inventory Verification (PIV) in South Korea. This field test was a success and the feedback provided by KINAC, IAEA, and national laboratory staff was used to direct efforts to improve the instrument this year. Key points in this report include measurement results frommore » PIV, analysis of spectra with commercially available Ortec U235 and PC-FRAM, and completion of tripod and tungsten collimator and integration of user feedback.« less

Assessment of isometric muscle strength and rate of torque development with hand-held dynamometry: Test-retest reliability and relationship with gait velocity after stroke.

PubMed

Mentiplay, Benjamin F; Tan, Dawn; Williams, Gavin; Adair, Brooke; Pua, Yong-Hao; Bower, Kelly J; Clark, Ross A

2018-04-27

Isometric rate of torque development examines how quickly force can be exerted and may resemble everyday task demands more closely than isometric strength. Rate of torque development may provide further insight into the relationship between muscle function and gait following stroke. Aims of this study were to examine the test-retest reliability of hand-held dynamometry to measure isometric rate of torque development following stroke, to examine associations between strength and rate of torque development, and to compare the relationships of strength and rate of torque development to gait velocity. Sixty-three post-stroke adults participated (60 years, 34 male). Gait velocity was assessed using the fast-paced 10 m walk test. Isometric strength and rate of torque development of seven lower-limb muscle groups were assessed with hand-held dynamometry. Intraclass correlation coefficients were calculated for reliability and Spearman's rho correlations were calculated for associations. Regression analyses using partial F-tests were used to compare strength and rate of torque development in their relationship with gait velocity. Good to excellent reliability was shown for strength and rate of torque development (0.82-0.97). Strong associations were found between strength and rate of torque development (0.71-0.94). Despite high correlations between strength and rate of torque development, rate of torque development failed to provide significant value to regression models that already contained strength. Assessment of isometric rate of torque development with hand-held dynamometry is reliable following stroke, however isometric strength demonstrated greater relationships with gait velocity. Further research should examine the relationship between dynamic measures of muscle strength/torque and gait after stroke. Copyright © 2018 Elsevier Ltd. All rights reserved.

Novel hand-held device for exhaled nitric oxide-analysis in research and clinical applications.

PubMed

Hemmingsson, Tryggve; Linnarsson, Dag; Gambert, Rudolf

2004-12-01

Changes in expired nitric oxide (NO) occur in airway inflammation and have proved to be important in the monitoring of inflammatory disease processes such as asthma. We set out to develop a novel hand-held NO-analyzer with a performance comparable to the present more costly and complex chemiluminescence instruments. The new device is based on a specially designed electrochemical sensor, where we have developed a novel sampling and analysis technology, compensating for the relatively slow response properties of the electrochemical sensor technique. A Lowest Detection Limit in NO-analysis from reference gas tests of less than 3 ppb and a response time of 15 seconds together with an average precision in human breath measurements of 1.4 ppb were obtained. We also show an agreement with the existing 'gold standard' FENO measurement technique, within 0.5 ppb in a group of 19 subjects together with a high linearity and accuracy compared to reference gases. The new analyzer enables affordable monitoring of inflammatory airway diseases in research and routine clinical practice.

Hand-transmitted vibration and biodynamic response of the human hand-arm: a critical review.

PubMed

Dong, R G; Rakheja, S; Schopper, A W; Han, B; Smutz, W P

2001-01-01

Hand-arm vibration syndrome (HAVS) has been associated with prolonged exposure to vibration transmitted to the human hand-arm system from hand-held power tools, vibrating machines, or hand-held vibrating workpieces. The biodynamic response of the human hand and arm to hand transmitted vibration (HTV) forms an essential basis for effective evaluations of exposures, vibration-attenuation mechanisms, and potential injury mechanisms. The biodynamic response to HTV and its relationship to HAVS are critically reviewed and discussed to highlight the advances and the need for further research. In view of its strong dependence on the nature of HTV and the lack of general agreement on the characteristics of HTV, the reported studies are first reviewed to enhance an understanding of HTV and related issues. The characteristics of HTV and relevant unresolved issues are discussed on the basis of measured data, proposed standards, and measurement methods, while the need for further developments in measurement systems is emphasized. The studies on biodynamic response and their findings are grouped into four categories based on the methodology used and the objective. These include studies on (1) through-the-hand-arm response, expressed in terms of vibration transmissibility; (2) to-the-hand response, expressed in terms of the force-motion relationship of the hand-arm system; (3) to-the-hand biodynamic response function, expressed in terms of vibration energy absorption; and (4) computer modeling of the biodynamic response characteristics.

Automatic detection of a hand-held needle in ultrasound via phased-based analysis of the tremor motion

NASA Astrophysics Data System (ADS)

Beigi, Parmida; Salcudean, Septimiu E.; Rohling, Robert; Ng, Gary C.

2016-03-01

This paper presents an automatic localization method for a standard hand-held needle in ultrasound based on temporal motion analysis of spatially decomposed data. Subtle displacement arising from tremor motion has a periodic pattern which is usually imperceptible in the intensity image but may convey information in the phase image. Our method aims to detect such periodic motion of a hand-held needle and distinguish it from intrinsic tissue motion, using a technique inspired by video magnification. Complex steerable pyramids allow specific design of the wavelets' orientations according to the insertion angle as well as the measurement of the local phase. We therefore use steerable pairs of even and odd Gabor wavelets to decompose the ultrasound B-mode sequence into various spatial frequency bands. Variations of the local phase measurements in the spatially decomposed input data is then temporally analyzed using a finite impulse response bandpass filter to detect regions with a tremor motion pattern. Results obtained from different pyramid levels are then combined and thresholded to generate the binary mask input for the Hough transform, which determines an estimate of the direction angle and discards some of the outliers. Polynomial fitting is used at the final stage to remove any remaining outliers and improve the trajectory detection. The detected needle is finally added back to the input sequence as an overlay of a cloud of points. We demonstrate the efficiency of our approach to detect the needle using subtle tremor motion in an agar phantom and in-vivo porcine cases where intrinsic motion is also present. The localization accuracy was calculated by comparing to expert manual segmentation, and presented in (mean, standard deviation and root-mean-square error) of (0.93°, 1.26° and 0.87°) and (1.53 mm, 1.02 mm and 1.82 mm) for the trajectory and the tip, respectively.

Hand-Held Photometer for Instant On-Spot Quantification of Nucleic Acids, Proteins, and Cells.

PubMed

Li, Shi-Hao; Jain, Abhinav; Tscharntke, Timo; Arnold, Tobias; Trau, Dieter W

2018-02-20

This paper presents a novel hand-held photometer, termed "Photopette", for on-spot absorbance measurements of biochemical analytes. The Photopette is a multicomponent, highly portable device with an overall weight of 160 g, which fits within 202 mm × 47 mm × 42 mm. Designed in the form factor of a micropipette, Photopette integrates a photodiode detector with light emitting diodes (LEDs) to form a highly customizable photometer which supports a wide variety of applications within the wavelengths between 260 and 1050 nm. A dual-purpose disposable reflective tip was designed to act as a sample holder and a light-reflecting system, which is in stark contrast to the operation of mainstream spectrophotometers and photometers. Small volume analytes may be measured with low sample loss using this proprietary CuveTip. A user-friendly software application running on smart devices was developed to control and read the values from Photopette via a low-energy Bluetooth link. This one-step strategy allows measurements on-spot without sample transfer, minimizing cross-contamination and human error. The results reported in this paper demonstrate Photopette's great potential to quantify DNA, direct protein, and cell density directly within the laminar flow hood. Results are compared with a Nanodrop 2000c spectrophotometer, a mainstream spectrophotometer for small-volume measurements.

Synthetic isotope mixtures for the calibration of isotope amount ratio measurements of carbon

NASA Astrophysics Data System (ADS)

Russe, K.; Valkiers, S.; Taylor, P. D. P.

2004-07-01

Synthetic isotope mixtures for the calibration of carbon isotope amount ratio measurements have been prepared by mixing carbon tetrafluoride highly enriched in 13C with carbon tetrafluoride depleted in 13C. Mixing procedures based on volumetry and gravimetry are described. The mixtures served as primary measurement standards for the calibration of isotope amount ratio measurements of the Isotopic Reference Materials PEF1, NBS22 and USGS24. Thus SI-traceable measurements of absolute carbon isotope amount ratios have been performed for the first time without any hypothesis needed for a correction of oxygen isotope abundances, such as is the case for measurements on carbon dioxide. As a result, "absolute" carbon isotope amount ratios determined via carbon tetrafluoride have smaller uncertainties than those published for carbon dioxide. From the measurements of the Reference Materials concerned, the absolute carbon isotope amount ratio of Vienna Pee Dee Belemnite (VPDB)--the hypothetical material upon which the scale for relative carbon isotope ratio measurements is based--was calculated to be R13(VPDB) = (11 101 +/- 16) × 10-6.

A new approach for the screening of carotid lesions: a 'fast-track' method with the use of new generation hand-held ultrasound devices.

PubMed

Aboyans, V; Lacroix, P; Jeannicot, A; Guilloux, J; Bertin, F; Laskar, M

2004-09-01

We assessed the usefulness of fast-track neck sonography with a new-generation hand-held ultrasound scanner in the detection of > or =60% carotid stenosis. Patients with a past history of atherosclerotic disease or presence of risk factors were enrolled. All had fast-track carotid screening with a hand-held ultrasound scanner. Initial assessment was performed with our quick imaging protocol. A second examiner performed a conventional complete carotid duplex as gold-standard. We enrolled 197 consecutive patients with a mean age of 67 years (range 35-94). A carotid stenosis >60% was detected in 13 cases (6%). The sensitivity, specificity, positive and negative predictive value of fast-track sonography was 100%, 64%, 17% and 100%, respectively. Concomitant power Doppler imaging during the fast-track method did not improve accuracy. The use of a fast-track method with a hand-held ultrasound device can reduce the number of unnecessary carotid Duplex and enhance the screening efficiency without missing significant carotid stenoses.

SHIELDING AND DETECTOR RESPONSE CALCULATIONS PERTAINING TO CATEGORY 1 QUANTITIES OF PLUTONIUM AND HAND-HELD PLASTIC SCINTILLATORS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Couture, A.

2013-06-07

Nuclear facilities sometimes use hand-held plastic scintillator detectors to detect attempts to divert special nuclear material in situations where portal monitors are impractical. MCNP calculations have been performed to determine the neutron and gamma radiation field arising from a Category I quantity of weapons-grade plutonium in various shielding configurations. The shields considered were composed of combinations of lead and high-density polyethylene such that the mass of the plutonium plus shield was 22.7 kilograms. Monte-Carlo techniques were also used to determine the detector response to each of the shielding configurations. The detector response calculations were verified using field measurements of high-,more » medium-, and low- energy gamma-ray sources as well as a Cf-252 neutron source.« less

Utility of hand-held devices in diagnosis and triage of cardiovascular emergencies. Observations during implementation of a PACS-based system in an acute aortic syndrome (AAS) network.

PubMed

Matar, Ralph; Renapurkar, Rahul; Obuchowski, Nancy; Menon, Venu; Piraino, David; Schoenhagen, Paul

2015-01-01

Prompt diagnosis and early referral to specialized centers is critical for patients presenting with cardiovascular emergencies, including acute aortic syndromes (AAS). Prior data has suggested that mobile access to imaging studies with hand-held devices can accelerate diagnosis and management. We conducted a study to determine the diagnostic accuracy of a hand-held device compared to conventional dedicated work-stations for diagnosing a spectrum of cardiovascular emergencies, predominantly acute aortic pathology. This study included 104 cases who underwent computed tomography (CT)-scan during "on-call'' hours between January, 2013 and August, 2014 for suspected AAS. Assessment was performed on a hand-held device independently by two readers using an iPhone5 connected via secure connection to web-based PACS servers. The subsequent interpretation from a dedicated workstation coupled with the diagnosis at the time of discharge was used as the reference standard for determining the presence or absence of an acute abnormality. Sensitivity and Specificity were calculated on a per patient basis. Readers' sensitivity and specificity using the hand-held device to diagnose acute chest pathology were calculated. Hand-held device evaluation was determined to have a sensitivity of 85.2% and a specificity of 98.6% by reader A and a sensitivity of 96.3% and specificity of 100% by reader B. Of 103 cases interpreted by both readers, the readers agreed about the diagnosis in 98 cases (95.1%). This study demonstrates that hand-held devices can be a potential useful tool to assist in diagnosis and triage of patients presenting with cardiovascular emergencies. Further studies are needed to assess the impact of screen size and resolution. Copyright © 2015 Society of Cardiovascular Computed Tomography. Published by Elsevier Inc. All rights reserved.

A new hand-held microfluidic cytometer for evaluating irradiation damage by analysis of the damaged cells distribution.

PubMed

Wang, Junsheng; Fan, Zhiqiang; Zhao, Yile; Song, Younan; Chu, Hui; Song, Wendong; Song, Yongxin; Pan, Xinxiang; Sun, Yeqing; Li, Dongqing

2016-03-17

Space radiation brings uneven damages to cells. The detection of the distribution of cell damage plays a very important role in radiation medicine and the related research. In this paper, a new hand-held microfluidic flow cytometer was developed to evaluate the degree of radiation damage of cells. The device we propose overcomes the shortcomings (e.g., large volume and high cost) of commercial flow cytometers and can evaluate the radiation damage of cells accurately and quickly with potential for onsite applications. The distribution of radiation-damaged cells is analyzed by a simultaneous detection of immunofluorescence intensity of γ-H2AX and resistance pulse sensor (RPS) signal. The γ-H2AX fluorescence intensity provides information of the degree of radiation damage in cells. The ratio of the number of cells with γ-H2AX fluorescence signals to the total numbers of cells detected by RPS indicates the percentage of the cells that are damaged by radiation. The comparison experiment between the developed hand-held microfluidic flow cytometer and a commercial confocal microscope indicates a consistent and comparable detection performance.

A new hand-held microfluidic cytometer for evaluating irradiation damage by analysis of the damaged cells distribution

NASA Astrophysics Data System (ADS)

Wang, Junsheng; Fan, Zhiqiang; Zhao, Yile; Song, Younan; Chu, Hui; Song, Wendong; Song, Yongxin; Pan, Xinxiang; Sun, Yeqing; Li, Dongqing

2016-03-01

Space radiation brings uneven damages to cells. The detection of the distribution of cell damage plays a very important role in radiation medicine and the related research. In this paper, a new hand-held microfluidic flow cytometer was developed to evaluate the degree of radiation damage of cells. The device we propose overcomes the shortcomings (e.g., large volume and high cost) of commercial flow cytometers and can evaluate the radiation damage of cells accurately and quickly with potential for onsite applications. The distribution of radiation-damaged cells is analyzed by a simultaneous detection of immunofluorescence intensity of γ-H2AX and resistance pulse sensor (RPS) signal. The γ-H2AX fluorescence intensity provides information of the degree of radiation damage in cells. The ratio of the number of cells with γ-H2AX fluorescence signals to the total numbers of cells detected by RPS indicates the percentage of the cells that are damaged by radiation. The comparison experiment between the developed hand-held microfluidic flow cytometer and a commercial confocal microscope indicates a consistent and comparable detection performance.

Application of computer image enhancement techniques to shuttle hand-held photography

NASA Technical Reports Server (NTRS)

David, B. E.

1986-01-01

With the advent of frequent Space Transportation System Shuttle missions, photography from hyperaltitudes stands to become an accessible and convenient resource for scientists and environmental managers. As satellite products (such as LANDSAT) continue to spiral in costs, all but the most affluent consumer is finding Earth imagery from space to be more and more unavailable. Therefore, the potential for Shuttle photography to serve a wide variety of users is increasing. However, despite the popularity of photos from space as public relations tools and report illustrations, little work has been performed to prove their scientific worth beyond that as basic mapping bases. It is the hypothesis of this project that hand-held Earth photography from the Space Shuttle has potentially high scientific merit and that primary data can be extracted. In effect, Shuttle photography should be considered a major remote sensing information resource.

The GSFC Mark-2 three band hand-held radiometer. [thematic mapper for ground truth data collection

NASA Technical Reports Server (NTRS)

Tucker, C. J.; Jones, W. H.; Kley, W. A.; Sundstrom, G. J.

1980-01-01

A self-contained, portable, hand-radiometer designed for field usage was constructed and tested. The device, consisting of a hand-held probe containing three sensors and a strap supported electronic module, weighs 4 1/2 kilograms. It is powered by flashlight and transistor radio batteries, utilizes two silicon and one lead sulfide detectors, has three liquid crystal displays, sample and hold radiometric sampling, and its spectral configuration corresponds to LANDSAT-D's thematic mapper bands. The device was designed to support thematic mapper ground-truth data collection efforts and to facilitate 'in situ' ground-based remote sensing studies of natural materials. Prototype instruments were extensively tested under laboratory and field conditions with excellent results.

Hand-held triangulation laser profilometer with audio output for blind people Profilométre laser à triangulation tenu en main avec sortie sonare pour non-voyants

NASA Astrophysics Data System (ADS)

Farcy, R.; Damaschini, R.

1998-06-01

We describe a device currently under industrial development which will give to the blind a means of three-dimensional space perception. It consists of a 350 g hand-held triangulating laser telemeter including electronic parts and batteries, with auditory feedback either inside the apparatus or close to the ear. The microprocessor unit converts in real time the distance measured by the telemeter into a musical note. Scanning the space with an adequate movement of the hand produces musical lines corresponding to the profiles of the environment. We discuss the optical configuration of the system relative to our first year of clinical experimentation.

InfraCAM (trade mark): A Hand-Held Commercial Infrared Camera Modified for Spaceborne Applications

NASA Technical Reports Server (NTRS)

Manitakos, Daniel; Jones, Jeffrey; Melikian, Simon

1996-01-01

In 1994, Inframetrics introduced the InfraCAM(TM), a high resolution hand-held thermal imager. As the world's smallest, lightest and lowest power PtSi based infrared camera, the InfraCAM is ideal for a wise range of industrial, non destructive testing, surveillance and scientific applications. In addition to numerous commercial applications, the light weight and low power consumption of the InfraCAM make it extremely valuable for adaptation to space borne applications. Consequently, the InfraCAM has been selected by NASA Lewis Research Center (LeRC) in Cleveland, Ohio, for use as part of the DARTFire (Diffusive and Radiative Transport in Fires) space borne experiment. In this experiment, a solid fuel is ignited in a low gravity environment. The combustion period is recorded by both visible and infrared cameras. The infrared camera measures the emission from polymethyl methacrylate, (PMMA) and combustion products in six distinct narrow spectral bands. Four cameras successfully completed all qualification tests at Inframetrics and at NASA Lewis. They are presently being used for ground based testing in preparation for space flight in the fall of 1995.

Hand-Held Units for Short-Range Wireless Biotelemetry

NASA Technical Reports Server (NTRS)

Miranda, Felix A.; Simons, Rainee N.

2008-01-01

Special-purpose hand-held radiotransceiver units have been proposed as means of short-range radio powering and interrogation of surgically implanted microelectromechanical sensors and actuators. These units are based partly on the same principles as those of the units described in "Printed Multi- Turn Loop Antennas for RF Biotelemetry" (LEW-17879-1), NASA Tech Briefs, Vol. 31, No. 6 (June 2007), page 48. Like the previously reported units, these units would make it unnecessary to have wire connections between the implanted devices and the external equipment used to activate and interrogate them. Like a unit of the previously reported type, a unit of the type now proposed would include a printed-circuit antenna on a dielectric substrate. The antenna circuitry would include integrated surface-mount inductors for impedance tuning. Circuits for processing the signals transmitted and received by the antenna would be included on the substrate. During operation, the unit would be positioned near (but not in electrical contact with) a human subject, in proximity to a microelectromechanical sensor or actuator that has been surgically implanted in the subject. It has been demonstrated that significant electromagnetic coupling with an implanted device could be established at a distance of as much as 4 in. (.10 cm). During operation in the interrogation mode, the antenna of the unit would receive a radio telemetry signal transmitted by the surgically implanted device. The antenna substrate would have dimensions of approximately 3.25 by 3.75 inches (approximately 8.3 by 9.5 cm). The substrate would have a thickness of the order of 30 mils (of the order of a somewhat less than a millimeter). The substrate would be made of low-radiofrequency- loss dielectric material that could be, for example, fused quartz, alumina, or any of a number of commercially available radio-frequency dielectric composite materials. The antenna conductors would typically be made of copper or a

Aragonite-Calcite Inversion During Biogenic Carbonate Sampling: Considerations for Interpreting Isotopic Measurements in Paleoclimate Studies

NASA Astrophysics Data System (ADS)

Waite, A. J.; Swart, P. K.

2011-12-01

As aragonite is the metastable polymorph of calcium carbonate, it lends itself to monotropic inversion to the more stable polymorph, calcite. This inversion is possible through an increase in the temperature and pressure conditions to which the sample is exposed and, although first noted nearly a century ago, has been primarily discussed in the context of sample roasting prior to analyses in paleoclimatological studies. Over the last several decades, however, researchers have found evidence to suggest that the friction associated with the sampling of biogenic carbonates via milling/drilling also induces inversion. Furthermore, this inversion may be associated with a shift in measured oxygen isotopic values and ultimately have significant implications for the interpretation of paleoclimatic reconstructions. Despite this, the isotopic heterogeneity of biogenic aragonite skeletons makes the effects of inversion challenging to test and the subject remains underrepresented in the literature. Here we present a first order study into the effects of milling on both the mineralogy and isotopic compositions measured in sclerosponges, corals, and molluscs. X-Ray diffraction analysis of samples hand ground with a mortar and pestle reveal 100% aragonitic skeletons. Conversely, samples milled with a computerized micromill show measurable inversion to calcite. On average, percent inversion of aragonite to calcite for individual specimens was 15% for sclerosponges, 16% for corals, and 9% for molluscs. Isotopic data from these specimens show that the higher the percentage of aragonite inverted to calcite, the more depleted the measured oxygen isotopic values. In the largest of the datasets (sclerosponges), it is evident that the range of oxygen isotope values from milled samples (-0.02 to +0.84%) exceeds the range in values for those samples which were hand ground and showed no inversion (+0.53 to +0.90%). This, coupled with the strong correlation between the two variables

Development and characterization of a round hand-held silicon photomultiplier based gamma camera for intraoperative imaging

PubMed Central

Popovic, Kosta; McKisson, Jack E.; Kross, Brian; Lee, Seungjoon; McKisson, John; Weisenberger, Andrew G.; Proffitt, James; Stolin, Alexander; Majewski, Stan; Williams, Mark B.

2017-01-01

This paper describes the development of a hand-held gamma camera for intraoperative surgical guidance that is based on silicon photomultiplier (SiPM) technology. The camera incorporates a cerium doped lanthanum bromide (LaBr3:Ce) plate scintillator, an array of 80 SiPM photodetectors and a two-layer parallel-hole collimator. The field of view is circular with a 60 mm diameter. The disk-shaped camera housing is 75 mm in diameter, approximately 40.5 mm thick and has a mass of only 1.4 kg, permitting either hand-held or arm-mounted use. All camera components are integrated on a mobile cart that allows easy transport. The camera was developed for use in surgical procedures including determination of the location and extent of primary carcinomas, detection of secondary lesions and sentinel lymph node biopsy (SLNB). Here we describe the camera design and its principal operating characteristics, including spatial resolution, energy resolution, sensitivity uniformity, and geometric linearity. The gamma camera has an intrinsic spatial resolution of 4.2 mm FWHM, an energy resolution of 21.1 % FWHM at 140 keV, and a sensitivity of 481 and 73 cps/MBq when using the single- and double-layer collimators, respectively. PMID:28286345

Biolistic transfection of neuronal cultures using a hand-held gene gun

PubMed Central

O'Brien, John A; Lummis, Sarah C R

2009-01-01

Biolistic transfection is a technique in which subcellular-sized particles coated with DNA are accelerated to high velocity to propel them into cells. This method is applicable to tissues, cells and organelles, and can be used for both in vitro and in vivo transformations; with the right equipment, it is simple, rapid and efficient. Here we provide a detailed protocol for biolistic transfection of plasmids into cultured human embryonic kidney (HEK) 293 cells and organotypic brain slices using a hand-held gene gun. There are three major steps: (i) coating microcarriers with DNA, (ii) transferring the microcarriers into a cartridge to make a ‘bullet’, and (iii) firing the DNA-coated microcarriers into cells using a pulse of helium gas. The method can be readily adapted to other cell types and tissues. The protocol can be completed in 1–2 h. PMID:17406333

Raman scattering method and apparatus for measuring isotope ratios and isotopic abundances

DOEpatents

Harney, Robert C.; Bloom, Stewart D.

1978-01-01

Raman scattering is used to measure isotope ratios and/or isotopic abundances. A beam of quasi-monochromatic photons is directed onto the sample to be analyzed, and the resulting Raman-scattered photons are detected and counted for each isotopic species of interest. These photon counts are treated mathematically to yield the desired isotope ratios or isotopic abundances.

Background adaptive division filtering for hand-held ground penetrating radar

NASA Astrophysics Data System (ADS)

Lee, Matthew A.; Anderson, Derek T.; Ball, John E.; White, Julie L.

2016-05-01

The challenge in detecting explosive hazards is that there are multiple types of targets buried at different depths in a highlycluttered environment. A wide array of target and clutter signatures exist, which makes detection algorithm design difficult. Such explosive hazards are typically deployed in past and present war zones and they pose a grave threat to the safety of civilians and soldiers alike. This paper focuses on a new image enhancement technique for hand-held ground penetrating radar (GPR). Advantages of the proposed technique is it runs in real-time and it does not require the radar to remain at a constant distance from the ground. Herein, we evaluate the performance of the proposed technique using data collected from a U.S. Army test site, which includes targets with varying amounts of metal content, placement depths, clutter and times of day. Receiver operating characteristic (ROC) curve-based results are presented for the detection of shallow, medium and deeply buried targets. Preliminary results are very encouraging and they demonstrate the usefulness of the proposed filtering technique.

Assessment of Lower Limb Muscle Strength and Power Using Hand-Held and Fixed Dynamometry: A Reliability and Validity Study

PubMed Central

Perraton, Luke G.; Bower, Kelly J.; Adair, Brooke; Pua, Yong-Hao; Williams, Gavin P.; McGaw, Rebekah

2015-01-01

Introduction Hand-held dynamometry (HHD) has never previously been used to examine isometric muscle power. Rate of force development (RFD) is often used for muscle power assessment, however no consensus currently exists on the most appropriate method of calculation. The aim of this study was to examine the reliability of different algorithms for RFD calculation and to examine the intra-rater, inter-rater, and inter-device reliability of HHD as well as the concurrent validity of HHD for the assessment of isometric lower limb muscle strength and power. Methods 30 healthy young adults (age: 23±5yrs, male: 15) were assessed on two sessions. Isometric muscle strength and power were measured using peak force and RFD respectively using two HHDs (Lafayette Model-01165 and Hoggan microFET2) and a criterion-reference KinCom dynamometer. Statistical analysis of reliability and validity comprised intraclass correlation coefficients (ICC), Pearson correlations, concordance correlations, standard error of measurement, and minimal detectable change. Results Comparison of RFD methods revealed that a peak 200ms moving window algorithm provided optimal reliability results. Intra-rater, inter-rater, and inter-device reliability analysis of peak force and RFD revealed mostly good to excellent reliability (coefficients ≥ 0.70) for all muscle groups. Concurrent validity analysis showed moderate to excellent relationships between HHD and fixed dynamometry for the hip and knee (ICCs ≥ 0.70) for both peak force and RFD, with mostly poor to good results shown for the ankle muscles (ICCs = 0.31–0.79). Conclusions Hand-held dynamometry has good to excellent reliability and validity for most measures of isometric lower limb strength and power in a healthy population, particularly for proximal muscle groups. To aid implementation we have created freely available software to extract these variables from data stored on the Lafayette device. Future research should examine the reliability

Extra-oral dental radiography for disaster victims using a flat panel X-ray detector and a hand-held X-ray generator.

PubMed

Ohtani, M; Oshima, T; Mimasaka, S

2017-12-01

Forensic odontologists commonly incise the skin for post-mortem dental examinations when it is difficult to open the victim's mouth. However, it is prohibited by law to incise dead bodies without permission in Japan. Therefore, we attempted using extra-oral dental radiography, using a digital X-ray equipment with rechargeable batteries, to overcome this restriction. A phantom was placed in the prone position on a table, and three plain dental radiographs were used per case: "lateral oblique radiographs" for left and right posterior teeth and a "contact radiograph" for anterior teeth were taken using a flat panel X-ray detector and a hand-held X-ray generator. The resolving power of the images was measured by a resolution test chart, and the scattered X-ray dose was measured using an ionization chamber-type survey meter. The resolving power of the flat panel X-ray detector was 3.0 lp/mm, which was less than that of intra-oral dental methods, but the three extra-oral plain dental radiographs provided the overall dental information from outside of the mouth, and this approach was less time-consuming. In addition, the higher dose of scattered X-rays was laterally distributed, but the dose per case was much less than that of intra-oral dental radiographs. Extra-oral plain dental radiography can be used for disaster victim identification by dental methods even when it is difficult to open the mouth. Portable and rechargeable devices, such as a flat panel X-ray detector and a hand-held X-ray generator, are convenient to bring and use anywhere, even at a disaster scene lacking electricity and water.

Breast-density assessment with hand-held ultrasound: A novel biomarker to assess breast cancer risk and to tailor screening?

PubMed

Sanabria, Sergio J; Goksel, Orcun; Martini, Katharina; Forte, Serafino; Frauenfelder, Thomas; Kubik-Huch, Rahel A; Rominger, Marga B

2018-03-19

To assess feasibility and diagnostic accuracy of a novel hand-held ultrasound (US) method for breast density assessment that measures the speed of sound (SoS), in comparison to the ACR mammographic (MG) categories. ACR-MG density (a=fatty to d=extremely dense) and SoS-US were assessed in the retromamillary, inner and outer segments of 106 women by two radiographers. A conventional US system was used for SoS-US. A reflector served as timing reference for US signals transmitted through the breasts. Four blinded readers assessed average SoS (m/s), ΔSoS (segment-variation SoS; m/s) and the ACR-MG density. The highest SoS and ΔSoS values of the three segments were used for MG-ACR whole breast comparison. SoS-US breasts were examined in <2 min. Mean SoS values of densities a-d were 1,421 m/s (SD 14), 1,432 m/s (SD 17), 1,448 m/s (SD 20) and 1,500 m/s (SD 31), with significant differences between all groups (p<0.001). The SoS-US comfort scores and inter-reader agreement were significantly better than those for MG (1.05 vs. 2.05 and 0.982 vs. 0.774; respectively). A strong segment correlation between SoS and ACR-MG breast density was evident (r s =0.622, p=<0.001) and increased for full breast classification (r s =0.746, p=<0.001). SoS-US allowed diagnosis of dense breasts (ACR c and d) with sensitivity 86.2 %, specificity 85.2 % and AUC 0.887. Using hand-held SoS-US, radiographers measured breast density without discomfort, readers evaluated measurements with high inter-reader agreement, and SoS-US correlated significantly with ACR-MG breast-density categories. • The novel speed-of-sound ultrasound correlated significantly with mammographic ACR breast density categories. • Radiographers measured breast density without women discomfort or radiation. • SoS-US can be implemented on a standard US machine. • SoS-US shows potential for a quantifiable, cost-effective assessment of breast density.

Hand-Held Instrument Fights Acne, Tops Over-the-Counter Market

NASA Technical Reports Server (NTRS)

2007-01-01

Tyrell Inc., a Houston-based medical technologies company, was able to access engineering support in redesigning a heating element for a hand-held acne-fighting device through SATOP, NASA's Space Alliance Technology Outreach Program. SATOP put Tyrell in contact with The Boeing Company, which assessed the design and made several major contributions. The product, named Zeno, is now the highest selling over-the-counter medical device for the treatment of acne, and in 2006, Zeno was named the "SATOP Texas, Success Story of the Year." Zeno employs proprietary ClearPoint technology to provide relief of mild to moderate inflammatory acne by delivering a precisely controlled low-level dosage of heat to the blemish, causing the bacteria at the root of more than 90 percent of acne to self-destruct. Within its first year on the market, Zeno was cited by various publications for several awards, including Allure's 2005 "Best of Beauty," Marie Claire's "10 Best Gadgets for Girls," and Popular Science's 2005 "Best of What's New." A variation of the Zeno for use in treating herpetic lesions such as cold sores, by killing the virus that causes them, is currently undergoing FDA trials.

Hand-Held Volatilome Analyzer Based on Elastically Deformable Nanofibers.

PubMed

Yucel, Muge; Akin, Osman; Cayoren, Mehmet; Akduman, Ibrahim; Palaniappan, Alagappan; Liedberg, Bo; Hizal, Gurkan; Inci, Fatih; Yildiz, Umit Hakan

2018-04-17

This study reports on a hand-held volatilome analyzer for selective determination of clinically relevant biomarkers in exhaled breath. The sensing platform is based on electrospun polymer nanofiber-multiwalled carbon nanotube (MWCNT) sensing microchannels. Polymer nanofibers of poly(vinylidene fluoride) (PVDF), polystyrene (PS), and poly(methyl methacrylate) (PMMA) incorporated with MWCNT exhibits a stable response to interferences of humidity and CO 2 and provides selective deformations upon exposure of exhaled breath target volatilomes acetone and toluene, exhibiting correlation to diabetes and lung cancer, respectively. The sensing microchannels "P1" (PVDF-MWCNT), "P2" (PS-MWCNT), and "P3" (PMMA-MWCNT) are integrated with a microfluidic cartridge (μ-card) that facilitates collection and concentration of exhaled breath. The volatilome analyzer consists of a conductivity monitoring unit, signal conditioning circuitries and a low energy display module. A combinatorial operation algorithm was developed for analyzing normalized resistivity changes of the sensing microchannels upon exposure to breath in the concentration ranges between 35 ppb and 3.0 ppm for acetone and 1 ppb and 10 ppm for toluene. Subsequently, responses of volatilomes from individuals in the different risk groups of diabetes were evaluated for validation of the proposed methodology. We foresee that proposed methodology provides an avenue for rapid detection of volatilomes thereby enabling point of care diagnosis in high-risk group individuals.

Hand-held synchronous scan spectrometer for in situ and immediate detection of live/dead bacteria ratio

NASA Astrophysics Data System (ADS)

Li, Runze; Goswami, Umang; Walck, Matthew; Khan, Kasfia; Chen, Jie; Cesario, Thomas C.; Rentzepis, Peter M.

2017-11-01

The design, construction, and operation of a hand-held synchronously scanned, excitation-emission, double monochromator spectrometer is described. Data show that it is possible to record and display within minutes the fluorescence spectra and ratio of live/dead bacteria in situ. Excitation emission matrix contour plots display clearly bacteria fluorescence spectra before and after UV inactivation, respectively. The separation of the fluorescence band maxima of molecular components, such as tryptophan, tyrosine, and DNA, may be distinguished in the diffused fluorescence spectra of bacteria and mixtures.

Hand-held synchronous scan spectrometer for in situ and immediate detection of live/dead bacteria ratio.

PubMed

Li, Runze; Goswami, Umang; Walck, Matthew; Khan, Kasfia; Chen, Jie; Cesario, Thomas C; Rentzepis, Peter M

2017-11-01

The design, construction, and operation of a hand-held synchronously scanned, excitation-emission, double monochromator spectrometer is described. Data show that it is possible to record and display within minutes the fluorescence spectra and ratio of live/dead bacteria in situ. Excitation emission matrix contour plots display clearly bacteria fluorescence spectra before and after UV inactivation, respectively. The separation of the fluorescence band maxima of molecular components, such as tryptophan, tyrosine, and DNA, may be distinguished in the diffused fluorescence spectra of bacteria and mixtures.

High-Precision Measurement of 13C/12C Isotopic Ratio Using Gas Chromatography-Combustion-Cavity Ring-Down Spectroscopy

NASA Astrophysics Data System (ADS)

Saad, N.; Kuramoto, D. S.; Haase, C.; Crosson, E.; Tan, S.; Zare, R. N.

2009-12-01

Light stable isotope analysis, and in particular, compound specific isotopic analysis (CSIA), is a valuable tool to elucidate pathways and provide a better insight into biological, ecological, and geological systems. We present here the results of compound-specific isotopic carbon analysis of short chain hydrocarbons using the world’s first combination of gas chromatography, combustion interface, and cavity ring-down spectroscopy (GC-C-CRDS). Cavity ring-down spectroscopy (CRDS) is a highly sensitive optical spectroscopy, one application of which is to measure the stable isotopic ratios in small molecules. Because it uses a highly reflective optical cavity with many kilometers effective path length, CRDS provides some of the most sensitive and precise optical absorption measurements. Most optical spectroscopy isotopic analysis measures the quantities of each isotopologue independently using their distinct ro-vibrational spectra. The most common isotopes measured with optical spectroscopy are 13C and 12C in carbon dioxide. However, the isotopes of hydrogen, oxygen, and sulfur have also been measured. Unlike isotope ratio mass spectrometry (IRMS), optical spectroscopy can distinguish among isobars, which have essentially identical m/z ratios. The combination of chemical separation, chemical conversion, and CRDS makes a nearly universal tool for isotopic analysis of mixtures. In addition, CRDS can tolerate a variety of compounds mixed with the target. For example, CRDS can measure carbon dioxide and its isotopic 13C/12C ratio in the presence of oxygen. Using the novel GC-C-CRDS system, we injected a 75-microliter mixture of approximately equal quantities of methane, ethane, and propane into a gas chromatograph using helium as carrier gas. The methane, ethane, and propane were separated in time by 100 to 200 seconds after the chromatograph. Oxygen gas was added, and the hydrocarbons were combusted in a catalytic combustor with platinum and nickel, held at 1150oC. The

Catalog of Space Shuttle Earth Observations Hand-Held Photography: Space Transportation System (STS) 41-6 Mission

NASA Technical Reports Server (NTRS)

Nowakowski, Barbara S.; Palmer, Wesley F.

1985-01-01

This document catalogs Space Shuttle hand-held Earth observations photography which was collected on the Space Transportation System (STS) 41-G mission of October 1984. The catalog includes the following data for each of 2480 frames: geographical name, feature description, latitude and longitude, percentage of cloud cover, look direction and tilt, lens focal length, exposure evaluation, stereopairs, and orbit number. The catalog is a product of the Space Shuttle Earth Observations Project, Solar System Exploration Division, Space and Life Sciences Directorate, of the National Aeronautics and Space Administration, Lyndon B. Johnson Space Center.

Potential air contamination during CO2 angiography using a hand-held syringe: theoretical considerations and gas chromatography.

PubMed

Cho, David R; Cho, Kyung J; Hawkins, Irvin F

2006-01-01

To assess air contamination in the hand-held syringes currently used for CO2 delivery and to determine whether there is an association between their position and the rate of air contamination. Assessment of air contamination in the syringe (20 ml) included theoretical modeling, mathematical calculation, and gas chromatography (GC). The model was used with Fick's first law to calculate the diffusion of CO2 and the amount of air contamination. For GC studies, the syringes were placed in the upright, horizontal, and inverted positions and gas samples were obtained after 5, 10, 20, 30, and 60 min. All trials with each position for each sampling time were performed five times. The amounts of air contamination with time calculated mathematically were 5-10% less than those of GC. With the diffusivity of air-CO2 at 0.1599 cm2/sec (9.594 cm2/min), air contamination was calculated to be 60% at 60 min. With GC air contamination was 13% at 5 min, 31% at 20 min, 43% at 30 min, and 68% at 60 min. There was no difference in air contamination between the different syringe positions. Air contamination occurs in hand-held syringes filled with CO2 when they are open to the ambient air. The amounts of air contamination over time are similar among syringes placed in the upright, horizontal, and inverted positions.

Flexible CMOS low-noise amplifiers for beyond-3G wireless hand-held devices

NASA Astrophysics Data System (ADS)

Becerra-Alvarez, Edwin C.; Sandoval-Ibarra, Federico; de la Rosa, José M.

2009-05-01

This paper explores the use of reconfigurable Low-Noise Amplifiers (LNAs) for the implementation of CMOS Radio Frequency (RF) front-ends in the next generation of multi-standard wireless transceivers. Main circuit strategies reported so far for multi-standard LNAs are reviewed and a novel flexible LNA intended for Beyond-3G RF hand-held terminals is presented. The proposed LNA circuit consists of a two-stage topology that combines inductive-source degeneration with PMOS-varactor based tuning network and a programmable load to adapt its performance to different standard specifications without penalizing the circuit noise and with a reduced number of inductors as compared to previous reported reconfigurable LNAs. The circuit has been designed in a 90-nm CMOS technology to cope with the requirements of the GSM, WCDMA, Bluetooth and WLAN (IEEE 802.11b-g) standards. Simulation results, including technology and packaging parasitics, demonstrate correct operation of the circuit for all the standards under study, featuring NF<2.8dB, S21>13.3dB and IIP3>10.9dBm, over a 1.85GHz-2.4GHz band, with an adaptive power consumption between 17mW and 22mW from a 1-V supply voltage. Preliminary experimental measurements are included, showing a correct reconfiguration operation within the operation band.

Hand-held hyperspectral imager for chemical/biological and environmental applications

NASA Astrophysics Data System (ADS)

Hinnrichs, Michele; Piatek, Bob

2004-03-01

A small, hand held, battery operated imaging infrared spectrometer, Sherlock, has been developed by Pacific Advanced Technology and was field tested in early 2003. The Sherlock spectral imaging camera has been designed for remote gas leak detection, however, the architecture of the camera is versatile enough that it can be applied to numerous other applications such as homeland security, chemical/biological agent detection, medical and pharmaceutical applications as well as standard research and development. This paper describes the Sherlock camera, theory of operations, shows current applications and touches on potential future applications for the camera. The Sherlock has an embedded Power PC and performs real-time-image processing function in an embedded FPGA. The camera has a built in LCD display as well as output to a standard monitor, or NTSC display. It has several I/O ports, ethernet, firewire, RS232 and thus can be easily controlled from a remote location. In addition, software upgrades can be performed over the ethernet eliminating the need to send the camera back to the factory for a retrofit. Using the USB port a mouse and key board can be connected and the camera can be used in a laboratory environment as a stand alone imaging spectrometer.

3D indoor modeling using a hand-held embedded system with multiple laser range scanners

NASA Astrophysics Data System (ADS)

Hu, Shaoxing; Wang, Duhu; Xu, Shike

2016-10-01

Accurate three-dimensional perception is a key technology for many engineering applications, including mobile mapping, obstacle detection and virtual reality. In this article, we present a hand-held embedded system designed for constructing 3D representation of structured indoor environments. Different from traditional vehicle-borne mobile mapping methods, the system presented here is capable of efficiently acquiring 3D data while an operator carrying the device traverses through the site. It consists of a simultaneous localization and mapping(SLAM) module, a 3D attitude estimate module and a point cloud processing module. The SLAM is based on a scan matching approach using a modern LIDAR system, and the 3D attitude estimate is generated by a navigation filter using inertial sensors. The hardware comprises three 2D time-flight laser range finders and an inertial measurement unit(IMU). All the sensors are rigidly mounted on a body frame. The algorithms are developed on the frame of robot operating system(ROS). The 3D model is constructed using the point cloud library(PCL). Multiple datasets have shown robust performance of the presented system in indoor scenarios.

Development of a minimum performance standard for hand-held fire extinguishers as a replacement for Halon 1211 on civilian transport category aircraft

DOT National Transportation Integrated Search

2002-08-01

One or more Halon 1211 hand-held fire extinguishers are specified in Federal Aviation Regulation (FAR) Part 25.851 as a requirement on transport category aircraft with 31 or more seats. Halon 1211 has been linked to the destruction of the ozone layer...

Obtaining accurate glucose measurements from wild animals under field conditions: comparing a hand held glucometer with a standard laboratory technique in grey seals

PubMed Central

Turner, Lucy M.; Millward, Sebastian; Moss, Simon E. W.; Hall, Ailsa J.

2017-01-01

Abstract Glucose is an important metabolic fuel and circulating levels are tightly regulated in most mammals, but can drop when body fuel reserves become critically low. Glucose is mobilized rapidly from liver and muscle during stress in response to increased circulating cortisol. Blood glucose levels can thus be of value in conservation as an indicator of nutritional status and may be a useful, rapid assessment marker for acute or chronic stress. However, seals show unusual glucose regulation: circulating levels are high and insulin sensitivity is limited. Accurate blood glucose measurement is therefore vital to enable meaningful health and physiological assessments in captive, wild or rehabilitated seals and to explore its utility as a marker of conservation relevance in these animals. Point-of-care devices are simple, portable, relatively cheap and use less blood compared with traditional sampling approaches, making them useful in conservation-related monitoring. We investigated the accuracy of a hand-held glucometer for ‘instant’ field measurement of blood glucose, compared with blood drawing followed by laboratory testing, in wild grey seals (Halichoerus grypus), a species used as an indicator for Good Environmental Status in European waters. The glucometer showed high precision, but low accuracy, relative to laboratory measurements, and was least accurate at extreme values. It did not provide a reliable alternative to plasma analysis. Poor correlation between methods may be due to suboptimal field conditions, greater and more variable haematocrit, faster erythrocyte settling rate and/or lipaemia in seals. Glucometers must therefore be rigorously tested before use in new species and demographic groups. Sampling, processing and glucose determination methods have major implications for conclusions regarding glucose regulation, and health assessment in seals generally, which is important in species of conservation concern and in development of circulating

Measurement of isotope abundance variations in nature by gravimetric spiking isotope dilution analysis (GS-IDA).

PubMed

Chew, Gina; Walczyk, Thomas

2013-04-02

Subtle variations in the isotopic composition of elements carry unique information about physical and chemical processes in nature and are now exploited widely in diverse areas of research. Reliable measurement of natural isotope abundance variations is among the biggest challenges in inorganic mass spectrometry as they are highly sensitive to methodological bias. For decades, double spiking of the sample with a mix of two stable isotopes has been considered the reference technique for measuring such variations both by multicollector-inductively coupled plasma mass spectrometry (MC-ICPMS) and multicollector-thermal ionization mass spectrometry (MC-TIMS). However, this technique can only be applied to elements having at least four stable isotopes. Here we present a novel approach that requires measurement of three isotope signals only and which is more robust than the conventional double spiking technique. This became possible by gravimetric mixing of the sample with an isotopic spike in different proportions and by applying principles of isotope dilution for data analysis (GS-IDA). The potential and principle use of the technique is demonstrated for Mg in human urine using MC-TIMS for isotopic analysis. Mg is an element inaccessible to double spiking methods as it consists of three stable isotopes only and shows great potential for metabolically induced isotope effects waiting to be explored.

Initial Usability Testing of a Hand-Held Electronic Logbook Prototype for the Human Research Facility

NASA Technical Reports Server (NTRS)

Berman, Andrea H.; Whitmore, Mihriban

1996-01-01

The Apple(R) Newton(TM) MessagePad 110 was flown aboard the KC-135 reduced gravity aircraft for microgravity usability testing. The Newton served as the initial hand-held electronic logbook prototype for the International Space Station (ISS) Human Research Facility (HRF). Subjects performed three different tasks with the Newton: (1) using the stylus to tap on different sections of the screen in order to launch an application and to select options within it; (2) using the stylus to write, and; (3) correcting handwriting recognition errors in a handwriting-intensive application. Subjects rated handwriting in microgravity 'Borderline' and had great difficulties finding a way in which to adequately restrain themselves at the lower body in order to have their hands free for the Newton. Handwriting recognition was rated 'Unacceptable,' but this issue is hardware-related and not unique to the microgravity environment. It is suggested that the restraint and handwriting issues are related and require further joint research with the current Handheld Electronic Logbook prototype: the Norand Pen*key Model #6300.

Hand skill measurement: a gauge for treatment.

PubMed

Bell, E; Jurek, K; Wilson, T

1976-02-01

Objective measurements of performance are vital with the increasing necessity to justify the need for occupational therapy services, and to conduct studies that measure the effectiveness of treatment procedures. This paper reports on a measurement of hand skill that was standardized by comparing hand skill performance among the able-bodied, or normal, population. The performance on this test o patients with various types of disabilities and the implications for treatment are discussed. For the paraplegic, the hand skill test indicates the need for occupational therapy services; for the quadriplegic, the test measures the effectiveness of functional orthotic devices; and for the hemiplegic, the hand skill test determines the potential for success in one aspect of self-care, dressing.

Precise and accurate isotope ratio measurements by ICP-MS.

PubMed

Becker, J S; Dietze, H J

2000-09-01

The precise and accurate determination of isotope ratios by inductively coupled plasma mass spectrometry (ICP-MS) and laser ablation ICP-MS (LA-ICP-MS) is important for quite different application fields (e.g. for isotope ratio measurements of stable isotopes in nature, especially for the investigation of isotope variation in nature or age dating, for determining isotope ratios of radiogenic elements in the nuclear industry, quality assurance of fuel material, for reprocessing plants, nuclear material accounting and radioactive waste control, for tracer experiments using stable isotopes or long-lived radionuclides in biological or medical studies). Thermal ionization mass spectrometry (TIMS), which used to be the dominant analytical technique for precise isotope ratio measurements, is being increasingly replaced for isotope ratio measurements by ICP-MS due to its excellent sensitivity, precision and good accuracy. Instrumental progress in ICP-MS was achieved by the introduction of the collision cell interface in order to dissociate many disturbing argon-based molecular ions, thermalize the ions and neutralize the disturbing argon ions of plasma gas (Ar+). The application of the collision cell in ICP-QMS results in a higher ion transmission, improved sensitivity and better precision of isotope ratio measurements compared to quadrupole ICP-MS without the collision cell [e.g., for 235U/238U approximately 1 (10 microg x L(-1) uranium) 0.07% relative standard deviation (RSD) vs. 0.2% RSD in short-term measurements (n = 5)]. A significant instrumental improvement for ICP-MS is the multicollector device (MC-ICP-MS) in order to obtain a better precision of isotope ratio measurements (with a precision of up to 0.002%, RSD). CE- and HPLC-ICP-MS are used for the separation of isobaric interferences of long-lived radionuclides and stable isotopes by determination of spallation nuclide abundances in an irradiated tantalum target.

Towards absolute laser spectroscopic CO2 isotope ratio measurements

NASA Astrophysics Data System (ADS)

Anyangwe Nwaboh, Javis; Werhahn, Olav; Ebert, Volker

2017-04-01

Knowledge of isotope composition of carbon dioxide (CO2) in the atmosphere is necessary to identify sources and sinks of this key greenhouse gas. In the last years, laser spectroscopic techniques such as cavity ring-down spectroscopy (CRDS) and tunable diode laser absorption spectroscopy (TDLAS) have been shown to perform accurate isotope ratio measurements for CO2 and other gases like water vapour (H2O) [1,2]. Typically, isotope ratios are reported in literature referring to reference materials provided by e.g. the International Atomic Energy Agency (IAEA). However, there could be some benefit if field deployable absolute isotope ratio measurement methods were developed to address issues such as exhausted reference material like the Pee Dee Belemnite (PDB) standard. Absolute isotope ratio measurements would be particularly important for situations where reference materials do not even exist. Here, we present CRDS and TDLAS-based absolute isotope ratios (13C/12C ) in atmospheric CO2. We demonstrate the capabilities of the used methods by measuring CO2 isotope ratios in gas standards. We compare our results to values reported for the isotope certified gas standards. Guide to the expression of uncertainty in measurement (GUM) compliant uncertainty budgets on the CRDS and TDLAS absolute isotope ratio measurements are presented, and traceability is addressed. We outline the current impediments in realizing high accuracy absolute isotope ratio measurements using laser spectroscopic methods, propose solutions and the way forward. Acknowledgement Parts of this work have been carried out within the European Metrology Research Programme (EMRP) ENV52 project-HIGHGAS. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union. References [1] B. Kühnreich, S. Wagner, J. C. Habig,·O. Möhler, H. Saathoff, V. Ebert, Appl. Phys. B 119:177-187 (2015). [2] E. Kerstel, L. Gianfrani, Appl. Phys. B 92, 439-449 (2008).

A new miniature hand-held solar-blind reagentless standoff chemical, biological, and explosives (CBE) sensor

NASA Astrophysics Data System (ADS)

Hug, W. F.; Reid, R. D.; Bhartia, R.; Lane, A. L.

2008-04-01

Improvised explosive devices (IEDs), vehicle-borne improvised explosive devices (VBIEDs), and suicide bombers are a major threat to many countries and their citizenry. The ability to detect trace levels of these threats with a miniature, hand-held, reagentless, standoff sensor represents a major improvement in the state of the art of CBE surface sensors. Photon Systems, Inc., in collaboration with Jet Propulsion Laboratory, recently demonstrated a new technology hand-held sensor for reagentless, close-range, standoff detection and identification of trace levels CBE materials on surfaces. This targeted ultraviolet CBE (TUCBE) sensor is the result of an Army Phase I STTR program. The resulting 5lb, 5W, flashlight-sized sensor can discriminate CBE from background materials using a combination of deep UV excited resonance Raman (RR) and laser induced native fluorescence (LINF) emissions resulting from excitation by a new technology deep UV laser. Detection and identification is accomplished in less than 1ms. Standoff excitation of suspicious packages, vehicles, persons, and other objects that may contain hazardous materials is accomplished using wavelengths below 250nm where Raman and native fluorescence emissions occupy distinctly different wavelength regions. This enables simultaneous detection of RR and LINF emissions with no interferences. The sensor employs fused RR/LINF chemometric methods to extract the identity of targeted materials from background clutter. Photon Systems has demonstrated detection and identification of 100ng/cm2 of explosives materials at a distance of 1 meter using a sensor with 3.8 cm optical aperture. Expansion of the optical aperture to 38 cm in a lantern-sized sensor will enable similar detection and identification of CBE materials at standoff distances of 10 meters. As a result of excitation and detection in the deep UV and the use of a gated detection system, the sensor is solar blind and can operate in full daylight conditions.

Detection of Francisella tularensis within infected mouse tissues by using a hand-held PCR thermocycler.

PubMed

Emanuel, Peter A; Bell, Ryan; Dang, Jessica L; McClanahan, Rebecca; David, John C; Burgess, Robert J; Thompson, Joseph; Collins, Lisa; Hadfield, Ted

2003-02-01

The diagnosis of human cases of tularemia often relies upon the demonstration of an antibody response to Francisella tularensis or the direct culturing of the bacteria from the patient. Antibody response is not detectable until 2 weeks or more after infection, and culturing requires special media and suspicion of tularemia. In addition, handling live Francisella poses a risk to laboratory personnel due to the highly infectious nature of this pathogen. In an effort to develop a rapid diagnostic assay for tularemia, we investigated the use of TaqMan 5' hydrolysis fluorogenic PCR to detect the organism in tissues of infected mice. Mice were infected to produce respiratory tularemia. The fopA and tul4 genes of F. tularensis were amplified from infected spleen, lung, liver, and kidney tissues sampled over a 5-day period. The samples were analyzed using the laboratory-based Applied Biosystems International 7900 and the Smiths Detection-Edgewood BioSeeq, a hand-held portable fluorescence thermocycler designed for use in the field. A comparison of culturing and PCR for detection of bacteria in infected tissues shows that culturing was more sensitive than PCR. However, the results for culture take 72 h, whereas PCR results were available within 4 h. PCR was able to detect infection in all the tissues tested. Lung tissue showed the earliest response at 2 days when tested with the ABI 7900 and in 3 days when tested with the BioSeeq. The results were in agreement between the ABI 7900 and the BioSeeq when presented with the same sample. Template preparation may account for the loss of sensitivity compared to culturing techniques. The hand-held BioSeeq thermocycler shows promise as an expedient means of forward diagnosis of infection in the field.

Detection of Francisella tularensis within Infected Mouse Tissues by Using a Hand-Held PCR Thermocycler

PubMed Central

Emanuel, Peter A.; Bell, Ryan; Dang, Jessica L.; McClanahan, Rebecca; David, John C.; Burgess, Robert J.; Thompson, Joseph; Collins, Lisa; Hadfield, Ted

2003-01-01

The diagnosis of human cases of tularemia often relies upon the demonstration of an antibody response to Francisella tularensis or the direct culturing of the bacteria from the patient. Antibody response is not detectable until 2 weeks or more after infection, and culturing requires special media and suspicion of tularemia. In addition, handling live Francisella poses a risk to laboratory personnel due to the highly infectious nature of this pathogen. In an effort to develop a rapid diagnostic assay for tularemia, we investigated the use of TaqMan 5′ hydrolysis fluorogenic PCR to detect the organism in tissues of infected mice. Mice were infected to produce respiratory tularemia. The fopA and tul4 genes of F. tularensis were amplified from infected spleen, lung, liver, and kidney tissues sampled over a 5-day period. The samples were analyzed using the laboratory-based Applied Biosystems International 7900 and the Smiths Detection-Edgewood BioSeeq, a hand-held portable fluorescence thermocycler designed for use in the field. A comparison of culturing and PCR for detection of bacteria in infected tissues shows that culturing was more sensitive than PCR. However, the results for culture take 72 h, whereas PCR results were available within 4 h. PCR was able to detect infection in all the tissues tested. Lung tissue showed the earliest response at 2 days when tested with the ABI 7900 and in 3 days when tested with the BioSeeq. The results were in agreement between the ABI 7900 and the BioSeeq when presented with the same sample. Template preparation may account for the loss of sensitivity compared to culturing techniques. The hand-held BioSeeq thermocycler shows promise as an expedient means of forward diagnosis of infection in the field. PMID:12574268

Development of a Minimum Performance Standard for Hand-Held Fire Extinguishers as a Replacement for Halon 1211 on Civilian Transport Category Aircraft

NASA Astrophysics Data System (ADS)

Webster, Harry

2002-08-01

One or more Halon 1211 hand-held fire extinguishers are specified in Federal Aviation Regulation (FAR) Part 25.851 as a requirement on transport category aircraft with 31 or more seats. Halon 1211 has been linked to the destruction of the ozone layer and production of new Halon 1211 has been halted per the Montreal Protocol in 1993. The phase out of Halon 1211, as the hand-held firefighting agent of choice, for civilian transport category aircraft has necessitated the development of a Minimum Performance Standard (MPS) to evaluate replacement agents. The purpose of the MPS is to insure that there is no reduction in safety, both in terms of effectiveness in fighting onboard fires and toxicity to the passengers and crew. The MPS specifies two new tests that replacement agents must pass in addition to requiring national certifications such as provided by Underwriters Laboratories. The first test evaluates the "flooding" characteristics of the agent against a hidden in-flight fire. This test determines the ability of a streaming agent to function as a flooding agent. The second test evaluates the performance of the agent in fighting a terrorist fire scenario and the associated toxicity hazard. This test measures the agent's ability to extinguish a triple-seat fire in an aircraft cabin under in-flight conditions and the toxicity characteristics of both the neat agent and the products of decomposition. This MPS will insure that the replacement agents will meet or exceed the performance of Halon 1211 both in fighting fires and maintaining a safe breathing environment in aircraft cabins.

Demonstration of the B4C/NaIO4/PTFE Delay in the U.S. Army Hand-Held Signal

DTIC Science & Technology

2015-05-20

Figure 1. Partial cross section diagram of a hand-held signal showing the rocket motor , delay element, expelling charge, and pyrotechnic payload as...The black powder-based rocket motor , consisting of propellant pellets (G) encased in a cardboard tube, contains an axial core hole to accommodate the...that ignites the rocket motor . Simultaneously, the delay element is ignited and burns for an interval (preferably 5−6 s) before it ignites the black

Four dimensional hybrid ultrasound and optoacoustic imaging via passive element optical excitation in a hand-held probe

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fehm, Thomas Felix; Razansky, Daniel, E-mail: dr@tum.de; Faculty of Medicine, Technische Universität München, Munich

2014-10-27

Ultrasonography and optoacoustic imaging share powerful advantages related to the natural aptitude for real-time image rendering with high resolution, the hand-held operation, and lack of ionizing radiation. The two methods also possess very different yet highly complementary advantages of the mechanical and optical contrast in living tissues. Nonetheless, efficient integration of these modalities remains challenging owing to the fundamental differences in the underlying physical contrast, optimal signal acquisition, and image reconstruction approaches. We report on a method for hybrid acquisition and reconstruction of three-dimensional pulse-echo ultrasound and optoacoustic images in real time based on passive ultrasound generation with an opticalmore » absorber, thus avoiding the hardware complexity of active ultrasound generation. In this way, complete hybrid datasets are generated with a single laser interrogation pulse, resulting in simultaneous rendering of ultrasound and optoacoustic images at an unprecedented rate of 10 volumetric frames per second. Performance is subsequently showcased in phantom experiments and in-vivo measurements from a healthy human volunteer, confirming general clinical applicability of the method.« less

Four dimensional hybrid ultrasound and optoacoustic imaging via passive element optical excitation in a hand-held probe

NASA Astrophysics Data System (ADS)

Fehm, Thomas Felix; Deán-Ben, Xosé Luís; Razansky, Daniel

2014-10-01

Ultrasonography and optoacoustic imaging share powerful advantages related to the natural aptitude for real-time image rendering with high resolution, the hand-held operation, and lack of ionizing radiation. The two methods also possess very different yet highly complementary advantages of the mechanical and optical contrast in living tissues. Nonetheless, efficient integration of these modalities remains challenging owing to the fundamental differences in the underlying physical contrast, optimal signal acquisition, and image reconstruction approaches. We report on a method for hybrid acquisition and reconstruction of three-dimensional pulse-echo ultrasound and optoacoustic images in real time based on passive ultrasound generation with an optical absorber, thus avoiding the hardware complexity of active ultrasound generation. In this way, complete hybrid datasets are generated with a single laser interrogation pulse, resulting in simultaneous rendering of ultrasound and optoacoustic images at an unprecedented rate of 10 volumetric frames per second. Performance is subsequently showcased in phantom experiments and in-vivo measurements from a healthy human volunteer, confirming general clinical applicability of the method.

Establishment of one-axis vibration test system for measurement of biodynamic response of human hand-arm system.

PubMed

Shibata, Nobuyuki; Hosoya, Naoki; Maeda, Setsuo

2008-12-01

Prolonged exposure to hand-arm vibration (HAV) due to use of hand-held power tools leads to an increased occurrence of symptoms of disorders in the vascular, neurological, and osteo-articular systems of the upper limbs called hand-arm vibration syndrome (HAVS). Biodynamic responses of the hand-arm system to vibration can be suggestive parameters that give us better assessment of exposure to HAV and fundamental data for design of low-vibration-exposure power tools. Recently, a single axis hand-arm vibration system has been installed in the Japan National Institute of Occupational Safety and Health (NIOSH). The aims of this study were to obtain the fundamental dynamic characteristics of an instrumented handle and to validate the performance and measurement accuracy of the system applied to dynamic response measurement. A pseudo-random vibration signal with a frequency range of 5-1,250 Hz and a power spectrum density of 1.0 (m/s2)2/Hz was used in this study. First the dynamic response of the instrumented handle without any weight was measured. After this measurement, the dynamic response measurement of the handle with weights mounted on the handle was performed. The apparent mass of a weight itself was obtained by using the mass cancellation method. The mass of the measuring cap on the instrumented handle was well compensated by using the mass cancellation method. Based on the 10% error tolerance, this handle can reliably measure the dynamic response represented by an apparent mass with a minimum weight of 2.0 g in a frequency range of 10.0 to 1,000 Hz. A marked increase in the AM magnitude of the weights of 15 g and 20 g in frequency ranges greater than 800 Hz is attributed not to the fundamental resonance frequency of the handle with weights, but to the fixation of the weight to the measuring cap. In this aspect, the peak of the AM magnitude can be reduced and hence should not be an obstacle to the biodynamic response measurement of the human hand-arm system. On the

Is it Time to Replace Physical Examination with a Hand-Held Ultrasound Device?

PubMed Central

Kaul, Sanjiv

2014-01-01

Attempts at using physical examination (PE) go back centuries, with inspection, palpation, and percussion being the mainstay of this approach until 2 centuries ago when the stethoscope was invented and auscultation became probably the most important element of PE for patients with known or suspected cardiovascular disease (CVD). Despite its several limitations, PE is still used, sometimes as the only means, of evaluating and following patients with CVD. In this paper I shall argue for the substitution of this inaccurate and archaic approach by direct visualization of the heart using a hand-held ultrasound (HHU) device. I am not in any way suggesting the substitution of a comprehensive echocardiographic examination by an expert sonographer/echocardiographer by HHU in patients with significant CVD. Instead, I am arguing for the replacement of PE for evaluation of the heart at the point of care as well as at the bedside, simply because HHU is more accurate and provides more meaningful information. PMID:28465916

Is it Time to Replace Physical Examination with a Hand-Held Ultrasound Device?

PubMed

Kaul, Sanjiv

2014-01-01

Attempts at using physical examination (PE) go back centuries, with inspection, palpation, and percussion being the mainstay of this approach until 2 centuries ago when the stethoscope was invented and auscultation became probably the most important element of PE for patients with known or suspected cardiovascular disease (CVD). Despite its several limitations, PE is still used, sometimes as the only means, of evaluating and following patients with CVD. In this paper I shall argue for the substitution of this inaccurate and archaic approach by direct visualization of the heart using a hand-held ultrasound (HHU) device. I am not in any way suggesting the substitution of a comprehensive echocardiographic examination by an expert sonographer/echocardiographer by HHU in patients with significant CVD. Instead, I am arguing for the replacement of PE for evaluation of the heart at the point of care as well as at the bedside, simply because HHU is more accurate and provides more meaningful information.

Rapid, chemical-free breaking of microfluidic emulsions with a hand-held antistatic gun

PubMed Central

Shahi, Payam; Abate, Adam R.

2017-01-01

Droplet microfluidics can form and process millions of picoliter droplets with speed and ease, allowing the execution of huge numbers of biological reactions for high-throughput studies. However, at the conclusion of most experiments, the emulsions must be broken to recover and analyze their contents. This is usually achieved with demulsifiers, like perfluorooctanol and chloroform, which can interfere with downstream reactions and harm cells. Here, we describe a simple approach to rapidly and efficiently break microfluidic emulsions, which requires no chemicals. Our method allows one-pot multi-step reactions, making it useful for large scale automated processing of reactions requiring demulsification. Using a hand-held antistatic gun, we pulse emulsions with the electric field, coalescing ∼100 μl of droplets in ∼10 s. We show that while emulsions broken with chemical demulsifiers exhibit potent PCR inhibition, the antistatic-broken emulsions amplify efficiently. The ability to break emulsions quickly without chemicals should make our approach valuable for most demulsification needs in microfluidics. PMID:28794817

Three-dimensional multispectral hand-held optoacoustic imaging with microsecond-level delayed laser pulses

NASA Astrophysics Data System (ADS)

Deán-Ben, X. L.; Bay, Erwin; Razansky, Daniel

2015-03-01

Three-dimensional hand-held optoacoustic imaging comes with important advantages that prompt the clinical translation of this modality, with applications envisioned in cardiovascular and peripheral vascular disease, disorders of the lymphatic system, breast cancer, arthritis or inflammation. Of particular importance is the multispectral acquisition of data by exciting the tissue at several wavelengths, which enables functional imaging applications. However, multispectral imaging of entire three-dimensional regions is significantly challenged by motion artefacts in concurrent acquisitions at different wavelengths. A method based on acquisition of volumetric datasets having a microsecond-level delay between pulses at different wavelengths is described in this work. This method can avoid image artefacts imposed by a scanning velocity greater than 2 m/s, thus, does not only facilitate imaging influenced by respiratory, cardiac or other intrinsic fast movements in living tissues, but can achieve artifact-free imaging in the presence of more significant motion, e.g., abrupt displacements during handheld-mode operation in a clinical environment.

Hand-held portable desorption atmospheric pressure chemical ionization ion source for in situ analysis of nitroaromatic explosives.

PubMed

Jjunju, Fred P M; Maher, Simon; Li, Anyin; Syed, Sarfaraz U; Smith, Barry; Heeren, Ron M A; Taylor, Stephen; Cooks, R Graham

2015-10-06

A novel, lightweight (0.6 kg), solvent- and gas-cylinder-free, hand-held ion source based on desorption atmospheric pressure chemical ionization has been developed and deployed for the analysis of nitroaromatic explosives on surfaces in open air, offering portability for in-field analysis. A small, inexpensive, rechargeable lithium polymer battery was used to power the custom-designed circuitry within the device, which generates up to ±5 kV dc voltage to ignite a corona discharge plasma in air for up to 12 h of continuous operation, and allowing positive- and negative-ion mass spectrometry. The generated plasma is pneumatically transported to the surface to be interrogated by ambient air at a rate of 1-3.5 L/min, compressed using a small on-board diaphragm pump. The plasma source allows liquid or solid samples to be examined almost instantaneously without any sample preparation in the open environment. The advantages of low carrier gas and low power consumption (<6 W), as well as zero solvent usage, have aided in developing the field-ready, hand-held device for trigger-based, "near-real-time" sampling/ionization. Individual nitroaromatic explosives (such as 2,4,6-trinitrotoluene) can be easily detected in amounts as low as 5.8 pg with a linear dynamic range of at least 10 (10-100 pg), a relative standard deviation of ca. 7%, and an R(2) value of 0.9986. Direct detection of several nitroaromatic compounds in a complex mixture without prior sample preparation is demonstrated, and their identities are confirmed by tandem mass spectrometry fragmentation patterns.

So the Kids Are Busy, What Now? Teacher Perceptions of the Use of Hand-Held Game Consoles in West Australian Primary Classrooms

ERIC Educational Resources Information Center

O'Rourke, John; Main, Susan; Ellis, Michelle

2013-01-01

Games technology in the form of hand-held game consoles (HGCs) when focussed on specific academic skill development has the capacity to engage students in learning and in turn produce positive academic results. This current research explores teacher perceptions of the implementation of HGCs to enhance the development of mental maths skills (namely…

Hand-held dynamic visual noise reduces naturally occurring food cravings and craving-related consumption.

PubMed

Kemps, Eva; Tiggemann, Marika

2013-09-01

This study demonstrated the applicability of the well-established laboratory task, dynamic visual noise, as a technique for reducing naturally occurring food cravings and subsequent food intake. Dynamic visual noise was delivered on a hand-held computer device. Its effects were assessed within the context of a diary study. Over a 4-week period, 48 undergraduate women recorded their food cravings and consumption. Following a 2-week baseline, half the participants watched the dynamic visual noise display whenever they experienced a food craving. Compared to a control group, these participants reported less intense cravings. They were also less likely to eat following a craving and consequently consumed fewer total calories following craving. These findings hold promise for curbing unwanted food cravings and craving-driven consumption in real-world settings. Copyright © 2013 Elsevier Ltd. All rights reserved.

The Complimentary Role of Methoxy-Isobutyl-Isonitrile and Hand-Held Gamma Probe in Adamantinoma

PubMed Central

Maharaj, Masha; Korowlay, Nisaar; Ellmann, Prof

2016-01-01

Adamantinoma is a rare locally aggressive osteolytic tumor that is found 90% of the time in the diaphysis of the tibia with the remaining lesions found in the fibula and long tubular bones. A case of adamantinoma of the tibia is presented. The added value of nuclear medicine investigations in the workup of this patient is described. A three-phase whole body 99mTc-methylene diphosphonate bone and a whole body 99mTc-methoxy-isobutyl-isonitrile scans were complimentary in the demarcation of viable bone tumor and the assessment of the remainder of the bone and soft tissue to exclude other sites. Intra-operative assistance with a hand-held gamma probe, guided the biopsy of the most metabolically active tumor tissue. Histology revealed a biphasic tumor composed of epithelial and fibrous components, in keeping with an adamantinoma. PMID:26912979

Testing of an automated online EA-IRMS method for fast and simultaneous carbon content and stable isotope measurement of aerosol samples

NASA Astrophysics Data System (ADS)

Major, István; Gyökös, Brigitta; Túri, Marianna; Futó, István; Filep, Ágnes; Hoffer, András; Molnár, Mihály

2016-04-01

Comprehensive atmospheric studies have demonstrated that carbonaceous aerosol is one of the main components of atmospheric particulate matter over Europe. Various methods, considering optical or thermal properties, have been developed for quantification of the accurate amount of both organic and elemental carbon constituents of atmospheric aerosol. The aim of our work was to develop an alternative fast and easy method for determination of the total carbon content of individual aerosol samples collected on prebaked quartz filters whereby the mass and surface concentration becomes simply computable. We applied the conventional "elemental analyzer (EA) coupled online with an isotope ratio mass spectrometer (IRMS)" technique which is ubiquitously used in mass spectrometry. Using this technique we are able to measure simultaneously the carbon stable isotope ratio of the samples, as well. During the developing process, we compared the EA-IRMS technique with an off-line catalytic combustion method worked out previously at Hertelendi Laboratory of Environmental Studies (HEKAL). We tested the combined online total carbon content and stable isotope ratio measurement both on standard materials and real aerosol samples. Regarding the test results the novel method assures, on the one hand, at least 95% of carbon recovery yield in a broad total carbon mass range (between 100 and 3000 ug) and, on the other hand, a good reproducibility of stable isotope measurements with an uncertainty of ± 0.2 per mill. Comparing the total carbon results obtained by the EA-IRMS and the off-line catalytic combustion method we found a very good correlation (R2=0.94) that proves the applicability of both preparation method. Advantages of the novel method are the fast and simplified sample preparation steps and the fully automated, simultaneous carbon stable isotope ratio measurement processes. Furthermore stable isotope ratio results can effectively be applied in the source apportionment

Candidate Quality Measures for Hand Surgery.

PubMed

2017-11-01

Quality measures are tools used by physicians, health care systems, and payers to evaluate performance, monitor the outcomes of interventions, and inform quality improvement efforts. A paucity of quality measures exist that address hand surgery care. We completed a RAND/UCLA (University of California Los Angeles) Delphi Appropriateness process with the goal of developing and evaluating candidate hand surgery quality measures to be used for national quality measure development efforts. A consortium of 9 academic upper limb surgeons completed a RAND/UCLA Delphi Appropriateness process to evaluate the importance, scientific acceptability, usability, and feasibility of 44 candidate quality measures. These addressed hand problems the panelists felt were most appropriate for quality measure development. Panelists rated the measures on an ordinal scale between 1 (definitely not valid) and 9 (definitely valid) in 2 rounds (preliminary round and final round) with an intervening face-to-face discussion. Ratings from 1 to 3 were considered not valid, 4 to 6 as equivocal or uncertain, and 7 to 9 as valid. If no more than 2 of the 9 ratings were outside the 3-point range that included the median (1-3, 4-6, or 7-9), the panelists were considered to be in agreement. If 3 or more of the panelists' ratings of a measure were within the 1 to 3 range and 3 or more ratings were in the 7 to 9 range, the panelists were considered to be in disagreement. There was agreement on 43% (19) of the measures as important, 27% (12) as scientifically sound, 48% (21) as usable, and 59% (26) as feasible to complete. Ten measures met all 4 of these criteria and were, therefore, considered valid measurements of quality. Quality measures that were developed address outcomes (patient-reported outcomes for assessment and improvement of function) and processes of care (utilization rates of imaging, antibiotics, occupational therapy, ultrasound, and operative treatment). The consortium developed 10

Hand-held microwave search detector

NASA Astrophysics Data System (ADS)

Daniels, David J.; Philippakis, Mike

2005-05-01

This paper describes the further development of a patented, novel, low cost, microwave search detector using noise radar technology operating in the 27-40GHz range of frequencies, initially reported in SPIE 2004. Initial experiments have shown that plastic explosives, ceramics and plastic material hidden on the body can be detected with the system. This paper considers the basic physics of the technique and reports on the development of a initial prototype system for hand search of suspects and addresses the work carried out on optimisation of PD and FAR. The radar uses a novel lens system and the design and modelling of this for optimum depth of field of focus will be reported.

Cellphone-Based Hand-Held Microplate Reader for Point-of-Care Testing of Enzyme-Linked Immunosorbent Assays.

PubMed

Berg, Brandon; Cortazar, Bingen; Tseng, Derek; Ozkan, Haydar; Feng, Steve; Wei, Qingshan; Chan, Raymond Yan-Lok; Burbano, Jordi; Farooqui, Qamar; Lewinski, Michael; Di Carlo, Dino; Garner, Omai B; Ozcan, Aydogan

2015-08-25

Standard microplate based enzyme-linked immunosorbent assays (ELISA) are widely utilized for various nanomedicine, molecular sensing, and disease screening applications, and this multiwell plate batched analysis dramatically reduces diagnosis costs per patient compared to nonbatched or nonstandard tests. However, their use in resource-limited and field-settings is inhibited by the necessity for relatively large and expensive readout instruments. To mitigate this problem, we created a hand-held and cost-effective cellphone-based colorimetric microplate reader, which uses a 3D-printed opto-mechanical attachment to hold and illuminate a 96-well plate using a light-emitting-diode (LED) array. This LED light is transmitted through each well, and is then collected via 96 individual optical fibers. Captured images of this fiber-bundle are transmitted to our servers through a custom-designed app for processing using a machine learning algorithm, yielding diagnostic results, which are delivered to the user within ∼1 min per 96-well plate, and are visualized using the same app. We successfully tested this mobile platform in a clinical microbiology laboratory using FDA-approved mumps IgG, measles IgG, and herpes simplex virus IgG (HSV-1 and HSV-2) ELISA tests using a total of 567 and 571 patient samples for training and blind testing, respectively, and achieved an accuracy of 99.6%, 98.6%, 99.4%, and 99.4% for mumps, measles, HSV-1, and HSV-2 tests, respectively. This cost-effective and hand-held platform could assist health-care professionals to perform high-throughput disease screening or tracking of vaccination campaigns at the point-of-care, even in resource-poor and field-settings. Also, its intrinsic wireless connectivity can serve epidemiological studies, generating spatiotemporal maps of disease prevalence and immunity.

FE and MG Isotopic Analyses of Isotopically Unusual Presolar Silicate Grains

NASA Technical Reports Server (NTRS)

Nguyen, A. N.; Messenger, S.; Ito, M.; Rahman, Z.

2011-01-01

Interstellar and circumstellar silicate grains are thought to be Mg-rich and Fe-poor, based on astronomical observations and equilibrium condensation models of silicate dust formation in stellar outflows. On the other hand, presolar silicates isolated from meteorites have surprisingly high Fe contents and few Mg-rich grains are observed. The high Fe contents in meteoritic presolar silicates may indicate they formed by a non-equilibrium condensation process. Alternatively, the Fe in the stardust grains could have been acquired during parent body alteration. The origin of Fe in presolar silicates may be deduced from its isotopic composition. Thus far, Fe isotopic measurements of presolar silicates are limited to the Fe-54/Fe-56 ratios of 14 grains. Only two slight anomalies (albeit solar within error) were observed. However, these measurements suffered from contamination of Fe from the adjacent meteorite matrix, which diluted any isotopic anomalies. We have isolated four presolar silicates having unusual O isotopic compositions by focused ion beam (FIB) milling and obtained their undiluted Mg and Fe isotopic compositions. These compositions help to identify the grains stellar sources and to determine the source of Fe in the grains.

Data-driven Approaches to Teaching Stable Isotopes in Hydrology and Environmental Geochemistry

NASA Astrophysics Data System (ADS)

Jefferson, A.; Merchant, W. R.; Dees, D.; Griffith, E. M.; Ortiz, J. D.

2016-12-01

Stable isotopes have revolutionized our understanding of watershed hydrology and other earth science processes. However, students may struggle to correctly interpret isotope ratios and few students understand how isotope measurements are made. New laser-based technologies lower the barrier to entry for giving students hands on experience with isotope measurements and data analysis. We hypothesizedthat integrating such activities into the curriculum would increase student content knowledge, perceptions, and motivation to learn. This project assessed the impact that different pedagogical approaches have on student learning of stable isotope concepts in upper-division geoscience courses. An isotope hydrograph separation module was developed and taught for a Watershed Hydrology course, and a Rayleigh distillation activity was developed and deployed for Environmental Geochemistry and Sedimentology/Stratigraphy classes. Groups of students were exposed to this content via (1) a lecture-only format; (2) a paper-based data analysis activity; and (3) hands-on data collection, sometimes including spectrometer analysis. Pre- and post-tests measured gains in content knowledge while approaches to learning and motivational questionnaires instruments were used to identify the effects of the classroom environment on learning approaches and motivation. Focus group interviews were also conducted to verify the quantitative data. All instructional styles appear to be equally effective at increasing student content knowledge of stable isotopes in the geosciences, but future studies need to move beyond "exam question" style assessment of learning. Our results may reflect that hands-on experiences are not new to upper-level geosciences students, because this is the way that many classes are taught in the geosciences (labs, field trips). Thus, active learning approaches may not have had the impact they would with other groups. The "messiness" of hands-on activities and authentic research

Determination of nitrogen-15 isotope fractionation in tropine: evaluation of extraction protocols for isotope ratio measurement by isotope ratio mass spectrometry.

PubMed

Molinié, Roland; Kwiecień, Renata A; Silvestre, Virginie; Robins, Richard J

2009-12-01

N-Demethylation of tropine is an important step in the degradation of this compound and related metabolites. With the purpose of understanding the reaction mechanism(s) involved, it is desirable to measure the 15N kinetic isotope effects (KIEs), which can be accessed through the 15N isotope shift (Deltadelta15N) during the reaction. To measure the isotope fractionation in 15N during tropine degradation necessitates the extraction of the residual substrate from dilute aqueous solution without introducing artefactual isotope fractionation. Three protocols have been compared for the extraction and measurement of the 15N/14N ratio of tropine from aqueous medium, involving liquid-liquid phase partitioning or silica-C18 solid-phase extraction. Quantification was by gas chromatography (GC) on the recovered organic phase and delta15N values were obtained by isotope ratio measurement mass spectrometry (irm-MS). Although all the protocols used can provide satisfactory data and both irm-EA-MS and irm-GC-MS can be used to obtain the delta15N values, the most convenient method is liquid-liquid extraction from a reduced aqueous volume combined with irm-GC-MS. The protocols are applied to the measurement of 15N isotope shifts during growth of a Pseudomonas strain that uses tropane alkaloids as sole source of carbon and nitrogen. The accuracy of the determination of the 15N/14N ratio is sufficient to be used for the determination of 15N-KIEs. Copyright 2009 John Wiley & Sons, Ltd.

Grasland Stable Isotope Flux Measurements: Three Isotopomers of Carbon Dioxide Measured by QCL Spectroscopy

NASA Astrophysics Data System (ADS)

Zeeman, M. J.; Tuzson, B.; Eugster, W.; Werner, R. A.; Buchmann, N.; Emmenegger, L.

2007-12-01

To improve our understanding of greenhouse gas dynamics of managed ecosystems such as grasslands, we not only need to investigate the effects of management (e.g., grass cuts) and weather events (e.g., rainy days) on carbon dioxide fluxes, but also need to increase the time resolution of our measurements. Thus, for the first time, we assessed respiration and assimilation fluxes with high time resolution (5Hz) stable isotope measurements at an intensively managed farmland in Switzerland (Chamau, 400m ASL). Two different methods were used to quantify fluxes of carbon dioxide and associated fluxes of stable carbon isotopes: (1) the flux gradient method, and (2) the eddy covariance method. During a week long intensive measurement campaign, we (1) measured mixing ratios of carbon dioxide isotopomers (12C16O2, 12C16O18O, 13C16O2) with a Quantum Cascade Laser (QCL, Aerodyne Inc.) spectroscope and (2) collected air samples for isotope analyses (13C/12C) and (18O/16O) of carbon dioxide by Isotope Ratio Mass Spectrometry (IRMS, Finnigan) every two hours, concurrently along a height profile (z = 0.05; 0.10; 0.31; 2.15m). In the following week, the QCL setup was used for closed-path eddy covariance flux measurement of the carbon dioxide isotopomers, with the air inlet located next to an open-path Infra Red Gas Analyzers (IRGA, LiCor 7500) used simultaneously for carbon dioxide measurements. During this second week, an area of grass inside the footprint was cut and harvested after several days. The first results of in-field continuous QCL measurements of carbon dioxide mixing ratios and their stable isotopic ratios show good agreement with IRGA measurements and isotope analysis of flask samples by IRMS. Thus, QCL spectroscopy is a very promising tool for stable isotope flux investigations.

CO2 laser myringotomy with a hand-held otoscope and fiber optic delivery system: animal experimentation and preclinical trials

NASA Astrophysics Data System (ADS)

DeRowe, Ari; Ophir, Dov; Finkelstein, Y.; Katzir, Abraham

1993-07-01

CO2 laser myringotomy has previously been proven effective in patients with serous otitis media for short term aeration of the middle ear. However, the system based on a microscope and a coaxially aligned laser is cumbersome and expensive. Also, conventional optical fibers do not transmit CO2 laser energy ((lambda) equals 10.6 micrometers ). We have developed a silver halide optical fiber of diameter 0.9 mm and lengths of several meters, with high transmission at 10.6 micrometers . Using a hand held otoscope coupled to a fiberoptic delivery system CO2 laser myringotomies were performed first in guinea pigs and then in humans. In the animal model the feasibility of the procedure was proven. Different irradiation parameters were studied and a `dose dependent' relationship was found between the total energy used and the duration of a patent myringotomy. This system was used to perform CO2 laser myringotomies under local anesthesia in five patients with serous otitis media and conductive hearing loss. None of the patients complained of discomfort and no scarring was noted. All patients had subjective and audiometric documentation of hearing improvement. The average duration of a patent myringotomy was 21 days. In two patients the effusion recurred. CO2 laser myringotomy utilizing a hand held otoscope coupled to an optical fiber capable of transmitting CO2 laser energy may prove simple and effective in the treatment of serous otitis media.

Use of a hand-held bladder ultrasound scanner in the assessment of dehydration and monitoring response to treatment in a paediatric emergency department.

PubMed

Enright, Kevin; Beattie, Tom; Taheri, Sepideh

2010-10-01

Dehydration is a common concern in paediatric emergency care. Limited tools are available to assess reduced urine production, which is commonly cited as a reliable marker of dehydration. To evaluate the utility of a hand-held bladder ultrasound scanner in monitoring urine production in children attending the emergency department with suspected dehydration. A prospective pilot study was undertaken on a convenience sample of patients presenting with suspected dehydration. Serial bladder ultrasound scanning was performed to monitor urine output. Dehydration was assessed clinically using the WHO guide to dehydration assessment. Decisions about treatment and admission were made independently of the urine output measurements obtained using the bladder scanner. 45 children were studied. Using the WHO guide, 33 (73%) had mild dehydration, 8 (18%) had moderate dehydration and 4 (9%) had severe dehydration. There was a significant difference in estimated urine production between those admitted and those discharged (0.9±1.2 ml/kg/h vs 1.8±1.5 ml/kg/h, p=0.01) and between those with mild dehydration versus moderate/severe dehydration (2.3±1.5 ml/kg/h vs 0.6±0.7 ml/kg/h, p=0.0011). Urine output had been significantly reduced in those who had received an intravenous fluid bolus compared with those who had not (0.4±0.46 ml/kg/h vs 1.9±1.6 ml/kg/h, p=0.001). The hand-held bladder scanner is a convenient, non-invasive and objective adjunct in the assessment and management of children attending the emergency department with suspected dehydration.

Beyond Textbook Illustrations: Hand-Held Models of Ordered DNA and Protein Structures as 3D Supplements to Enhance Student Learning of Helical Biopolymers

ERIC Educational Resources Information Center

Jittivadhna, Karnyupha; Ruenwongsa, Pintip; Panijpan, Bhinyo

2010-01-01

Textbook illustrations of 3D biopolymers on printed paper, regardless of how detailed and colorful, suffer from its two-dimensionality. For beginners, computer screen display of skeletal models of biopolymers and their animation usually does not provide the at-a-glance 3D perception and details, which can be done by good hand-held models. Here, we…

Nitrogen isotope fractionation during archaeal ammonia oxidation: Coupled estimates from isotopic measurements of ammonium and nitrite

NASA Astrophysics Data System (ADS)

Mooshammer, Maria; Stieglmeier, Michaela; Bayer, Barbara; Jochum, Lara; Melcher, Michael; Wanek, Wolfgang

2014-05-01

Ammonia-oxidizing archaea (AOA) are ubiquitous in marine and terrestrial environments and knowledge about the nitrogen (N) isotope effect associated with their ammonia oxidation activity will allow a better understanding of natural abundance isotope ratios, and therefore N transformation processes, in the environment. Here we examine the kinetic isotope effect for ammonia oxidation in a pure soil AOA culture (Ca. Nitrososphaera viennensis) and a marine AOA enrichment culture. We estimated the isotope effect from both isotopic signatures of ammonium and nitrite over the course of ammonia oxidation. Estimates of the isotope effect based on the change in the isotopic signature of ammonium give valuable insight, because these estimates are not subject to the same concerns (e.g., accumulation of an intermediate) as estimates based on isotopic measurements of nitrite. Our results show that both the pure soil AOA culture and a marine AOA enrichment culture have similar but substantial isotope effect during ammonia consumption (31-34 per mill; based on ammonium) and nitrite production (43-45 per mill; based on nitrite). The 15N fractionation factors of both cultures tested fell in the upper range of the reported isotope effects for archaeal and bacterial ammonia oxidation (10-41 per mill) or were even higher than those. The isotope fractionation for nitrite production was significantly larger than for ammonium consumption, indicating that (1) some intermediate (e.g., hydroxylamine) of ammonia oxidation accumulates, allowing for a second 15N fractionation step to be expressed, (2) a fraction of ammonia oxidized is lost via gaseous N forms (e.g., NO or N2O), which is 15N-enriched or (3) a fraction of ammonium is assimilated into AOA biomass, biomass becoming 15N-enriched. The significance of these mechanisms will be explored in more detail for the soil AOA culture, based on isotope modeling and isotopic measurements of biomass and N2O.

Glucose concentration in capillary blood of dairy cows obtained by a minimally invasive lancet technique and determined with three different hand-held devices.

PubMed

Mair, B; Drillich, M; Klein-Jöbstl, D; Kanz, P; Borchardt, S; Meyer, L; Schwendenwein, I; Iwersen, M

2016-02-24

Dairy cows have a massive demand for glucose at the onset of lactation. A poor adaption to this period leads to an excessive negative energy balance with an increased risk for ketosis and impaired animal health and production. Besides the measurement of ketones, analysing the glucose concentration in blood is reported as helpful instrument for diagnosis and differentiation of ketosis. Monitoring metabolic parameters requires multiple blood sampling. In other species, new blood sampling techniques have been introduced in which small amounts of blood are rapidly analysed using electronic hand-held devices. The objective of this study was to evaluate the suitability of capillary blood for blood glucose measurement in dairy cows using the hand-held devices FreeStyle Precision (FSP, Abbott), GlucoMen LX Plus (GLX, A. Menarini) and the WellionVet GLUCO CALEA, (WGC, MED TRUST). In total, 240 capillary blood samples were obtained from dry and fresh lactating Holstein-Friesian cows. Blood was collected from the skin of the exterior vulva by using a lancet. For method comparison, additional blood samples were taken from a coccygeal vessel and analyzed in a laboratory. Glucose concentrations measured by a standard laboratory method were defined as the criterion standard. The Pearson correlation coefficients between the glucose concentrations analyzed in capillary blood with the devices and the reference were 73% for the FSP, 81% for the GLX and 41% for the WGC. Bland-Altman plots showed biases of -18.8 mg/dL for the FSP, -11.2 mg/dL for the GLX and +20.82 mg/dL for the WGC. The optimized threshold determined by a Receiver Operating Characteristics analysis to detect hyperglycemia using the FSP was 43 mg/dL with a sensitivity (Se) and specificity (Sp) of 76 and 80%. Using the GLX and WGC optimized thresholds were 49 mg/dL (Se = 92%, Sp = 85%) and 95 mg/dL (Se = 39%, Sp = 92%). The results of this study demonstrate good performance characteristics for the GLX

Utility of hand-held echocardiography in outpatient pediatric cardiology management.

PubMed

Riley, Alan; Sable, Craig; Prasad, Aparna; Spurney, Christopher; Harahsheh, Ashraf; Clauss, Sarah; Colyer, Jessica; Gierdalski, Marcin; Johnson, Ashley; Pearson, Gail D; Rosenthal, Joanna

2014-12-01

Adult patient series have shown hand-held echocardiography (echo) units (HHE) to be accurate for rapid diagnosis and triage. This is the first study to evaluate the ability of HHE to inform decision making in outpatient pediatric cardiology. New pediatric cardiology patients in outpatient clinics staffed by six pediatric cardiologists (experience 1-17 years) were prospectively enrolled if an echocardiogram (echo) was ordered during their initial visit. After history and physical examination and before a standard echo, the cardiologists performed a bedside HHE examination (GE Vscan 1.7-3.8 MHz), documented findings, and made a clinical decision. Diagnoses and decisions based on HHE were compared with final management after the standard echo. The study enrolled 101 subjects (ages 9 days to 19 years). The cardiologists considered HHE imaging adequate for decision making for 80 of the 101 subjects. For 77 of the 80 subjects with acceptable HHE imaging (68/68 normal and 9/12 abnormal standard echoes), the HHE-based primary diagnoses and decisions agreed with the final management. The sensitivity of HHE was 75 % (95 % confidence interval [CI] 43-94 %) and the positive predictive value 100 % (95 % CI 66-100 %) for pediatric heart disease. The agreement between standard echocardiography and HHE imaging was substantial (κ = 0.82). Excluding one of the least experienced cardiologists, HHE provided the basis for correct cardiac diagnoses and management for all the subjects with acceptable HHE imaging (58/58 normal and 9/9 abnormal echoes). In outpatient pediatric cardiology, HHE has potential as a tool to complement physical examination. Further investigation is needed to evaluate how value improves with clinical experience.

Hip- and knee-strength assessments using a hand-held dynamometer with external belt-fixation are inter-tester reliable.

PubMed

Thorborg, Kristian; Bandholm, Thomas; Hölmich, Per

2013-03-01

In football, ice-hockey, and track and field, injuries have been predicted, and hip- and knee-strength deficits quantified using hand-held dynamometry (HHD). However, systematic bias exists when testers of different sex and strength perform the measurements. Belt-fixation of the dynamometer may resolve this. The aim of the present study was therefore to examine the inter-tester reliability concerning strength assessments of isometric hip abduction, adduction, flexion, extension and knee-flexion strength, using HHD with external belt-fixation. Twenty-one healthy athletes (6 women), 30 (8.6) (mean (SD)) years of age, were included. Two physiotherapy students (1 female and 1 male) performed all the measurements after careful instruction and procedure training. Isometric hip abduction, adduction, flexion, extension, and knee-flexion strength were tested. The tester-order and hip-action order were randomised. No systematic between-tester differences (bias) were observed for any of the hip or knee actions. The intra-class correlation coefficients (ICC 2.1) ranged from 0.76 to 0.95. Furthermore, standard errors of measurement in per cent (SEM %) ranged from 5 to 11 %, and minimal detectable change in per cent (MDC %) from 14 to 29 % for the different hip and knee actions. The present study shows that isometric hip- and knee-strength measurements have acceptable inter-tester reliability at the group level, when testing strong individuals, using HHD with belt-fixation. This procedure is therefore perfectly suited for the evaluation and monitoring of strong athletes with hip, groin and hamstring injuries, some of the most common and troublesome injuries in sports. Diagnostic, Level III.

Eccentric and isometric shoulder rotator cuff strength testing using a hand-held dynamometer: reference values for overhead athletes.

PubMed

Cools, Ann M J; Vanderstukken, Fran; Vereecken, Frédéric; Duprez, Mattias; Heyman, Karel; Goethals, Nick; Johansson, Fredrik

2016-12-01

In order to provide science-based guidelines for injury prevention or return to play, regular measurement of isometric and eccentric internal (IR) and external (ER) rotator strength is warranted in overhead athletes. However, up to date, no normative database exists regarding these values, when measured with a hand-held dynamometer. Therefore, the purpose of the study was to provide a normative database on isometric and eccentric rotator cuff (RC) strength values in a sample of overhead athletes, and to discuss gender, age and sports differences. A HHD was used to measure RC strength in 201 overhead athletes between 18 and 50 years old from three different sports disciplines: tennis, volleyball and handball. Isometric as well as eccentric strength was measured in different shoulder positions. Outcome variables of interest were isometric ER and IR strength, eccentric ER strength, and intermuscular strength ratios ER/IR. Our results show significant side, gender and sports discipline differences in the isometric and eccentric RC strength. However, when normalized to body weight, gender differences often are absent. In general, strength differences are in favour of the dominant side, the male athletes and handball. Intermuscular ER/IR ratios showed gender, sports, and side differences. This normative database is necessary to help the clinician in the evaluation of RC strength in healthy and injured overhead athletes. In view of the preventive screening and return-to-play decisions in overhead athletes, normalization to body weight and calculating intermuscular ratios are key points in this evaluation. Diagnostic study, Level III.

In-situ measurement of sulfur isotopic ratios in zoned apatite crystals via SIMS: a new tool for interpreting dynamic sulfur behavior in magmas

NASA Astrophysics Data System (ADS)

Economos, R. C.; Boehnke, P.; Burgisser, A.

2017-12-01

Sulfur is an important element in igneous systems due to its impact on magma redox, its role in the formation of economically valuable ore deposits, and the influence of catastrophic volcanogenic sulfur degassing on global climate. The mobility and geochemical behavior of sulfur in magmas is complex due to its multi-valent (from S2- to S6+) and multi-phase (solid, immiscible liquid, gaseous, dissolved ions) nature. Sulfur behavior is closely linked with the evolution of oxygen fugacity (fO2) in magmas; the record of fO2 evolution is often difficult to extract from rock records, particularly for intrusive systems that undergo cyclical magmatic processes and crystallize to the solidus. We apply a novel method of measuring S isotopic ratios via secondary ion mass spectrometry (SIMS) in zoned apatite crystals that we interpret as a record of open-system magmatic processes. We analyzed the S concentration and isotopic variations preserved in multiple apatite crystals from single hand specimens from the Cadiz Valley Batholith, CA via electron microprobe and ion microprobe at UCLA. A single, isotopically homogeneous crystal of Durango apatite was characterized for absolute isotopic ratio for this study (UCLA-D1). Isotopic variations in single apatite crystals ranged from 0 to 3.8‰ δ34S and total variation within a single hand sample was 6.1‰ δ34S. High S concentration cores yielded high isotopic ratios while low S concentration rims yielded low isotopic ratios. We favor an explanation of a combination of magma mixing and open-system, ascent-driven degassing under moderately reduced conditions: fO2 at or below NNO +1, although the synchronous crystallization of apatite and anhydrite is also a viable scenario. These findings have implications for the coupled S and fO2 evolution of granitic plutons and suggest that in-situ apatite S isotopic measurements could be a powerful new tool for evaluating redox and S systematics in magmatic systems.

Measurements of Forest-Atmosphere Isotopic CO2 Exchange by Eddy Covariance

NASA Astrophysics Data System (ADS)

Wehr, R. A.; Munger, J. W.; Nelson, D. D.; McManus, J. B.; Zahniser, M. S.; Saleska, S. R.

2010-12-01

Isotopic CO2 flux measurements are a promising means for partitioning the net ecosystem exchange of CO2 into photosynthetic and respiratory components. This approach to partitioning is possible in principle because of the distinct isotopic signatures of respired and photosynthesized CO2, but has been infeasible in practice—especially in forests—because of the difficulty of measuring isotopic ratios with sufficient precision and time response for use in eddy covariance (EC) flux calculations. Recent advances in laser spectroscopic instrumentation have changed that. We report measurements of isotopic (13C and 18O) CO2 exchange made by eddy covariance at Harvard Forest between April and December, 2010. The measurements were made using a continuous-wave quantum cascade laser spectrometer (Aerodyne Research Inc.) sampling at 4 Hz and are, to our knowledge, the first EC isotopic flux measurements at a forest site. The spectrometer can measure δ13C and δ18O with internal precisions (standard deviation of 1-minute averages) of 0.03 ‰, and [CO2] with an internal precision of 15 ppb; the instrumental accuracy, calibration, and long-term stability are discussed in detail. The isotopic data are considered in relation to environmental variables (PAR, temperature, humidity, soil temperature and moisture), and a first attempt at flux partitioning using the isotopic fluxes is presented.

Perceiving the vertical distances of surfaces by means of a hand-held probe.

PubMed

Chan, T C; Turvey, M T

1991-05-01

Nine experiments were conducted on the haptic capacity of people to perceive the distances of horizontal surfaces solely on the basis of mechanical stimulation resulting from contacting the surfaces with a vertically held rod. Participants touched target surfaces with rods inside a wooden cabinet and reported the perceived surface location with an indicator outside the cabinet. The target surface, rod, and the participant's hand were occluded, and the sound produced in exploration was muffled. Properties of the probe (length, mass, moment of inertia, center of mass, and shape) were manipulated, along with surface distance and the method and angle of probing. Results suggest that for the most common method of probing, namely, tapping, perceived vertical distance is specific to a particular relation among the rotational inertia of the probe, the distance of the point of contact with the surface from the probe's center of percussion, and the inclination at contact of the probe to the surface. They also suggest that the probe length and the distance probed are independently perceivable. The results were discussed in terms of information specificity versus percept-percept coupling and parallels between selective attention in haptic and visual perception.

Isotopic Measurements of Organic Sulfonates From The Murchison Meteorite

NASA Technical Reports Server (NTRS)

Cooper, G. W.; Chang, S.; DeVincenzi, Donald L. (Technical Monitor)

1995-01-01

Organic sulfonates and phosphonates have been extracted from the Murchison meteorite for stable isotope measurements. Preliminary stable isotope measurements of individual alkyl sulfonates, R-SO3H (R=C(sub n)H(sub 2n+l)), are shown. These compounds were found in aqueous extracts of Murchison. Both groups show trends similar to other homologous series of organic compounds indigenous to Murchison. Molecular abundances decrease with increasing carbon number, and all possible isomers at each carbon number (through C-4) are present. Carbon isotope measurements of the sulfonates show a decrease in the C-13/C-12 ratio with increasing carbon number. The overall objectives of this project are to obtain dime element carbon, hydrogen, and sulfur - intramolecular isotopic analyses of individual sulfonates, and isotopic measurement of carbon and hydrogen of the phosphonates as a group. The Murchison meteorite is the best characterized carbonaceous chondrite with respect to organic chemistry. The finding of organic sulfonates and phosphonates in Murchison is of interest because they are the first well-characterized series of sulfur and phosphorus containing organic compounds found in meteorites. Also, meteorites, comets, and interplanetary dust particles may have been involved in chemical evolution on the early Earth. Because of the critical role of organic phosphorus and sulfur in all living systems, it is particularly interesting to see examples of abiotic syntheses of these classes of compounds. The study of the isotopic composition of the sulfonates and phosphonates can yield insight into their possible interstellar origin as well as their mechanisms of synthesis in the early solar system. Previous isotopic analyses of other classes of organic compounds indigenous to meteorites, e.g., amino acids, carboxylic acids, and hydrocarbons indicate the possibility that interstellar molecules were incorporated into meteorite parent bodies. In these compounds the ratios of heavy to

Predicting meat quality traits of ovine m. semimembranosus, both fresh and following freezing and thawing, using a hand held Raman spectroscopic device.

PubMed

Fowler, Stephanie M; Schmidt, Heinar; van de Ven, Remy; Wynn, Peter; Hopkins, David L

2015-10-01

Complementary studies were conducted to determine the potential for a Raman spectroscopic hand held device to predict meat quality traits of fresh lamb m. semimembranosus (topside) after ageing and freezing/thawing. Spectra were collected from 80 fresh muscles at 24h and 5d PM, another 80 muscles were measured at 24h, 5d and following freezing/thawing. Shear force, cooking loss, sarcomere length, colour, particle size, collagen content, pH24, pHu, purge and thaw loss were also measured. Results indicated a potential to predict pHu (R(2)cv=0.59), pH24 (R(2)cv=0.48) and purge (R(2)cv=0.42) using spectra collected 24h PM. L* could be predicted using spectra collected 24h (R(2)cv=0.33) or 5d PM (R(2)cv=0.33). This suggests that Raman spectroscopy is suited to identifying carcases which deviate from the normal metabolic processes and related meat quality traits. Copyright © 2015. Published by Elsevier Ltd.

Hand-held dynamometer testing of the internal and external rotator musculature based on selected positions to establish normative data and unilateral ratios.

PubMed

Riemann, Bryan L; Davies, George J; Ludwig, Lauren; Gardenhour, Helen

2010-12-01

Objective documentation is needed of shoulder internal and external rotator strength using hand-held dynamometry in selected positions commonly used in a clinic. We compared strength measures and unilateral ratios between gender, limbs (dominant, nondominant), and 3 testing positions. We hypothesized that men would be stronger than women, the dominant shoulder would be stronger than the nondominant shoulder, and the seated neutral (0° adduction) and seated 30° abduction, 30° scaption, 30° diagonal (30°-30°-30°) positions would be stronger than the prone at 90°-90° position. Three positions (prone at 90°, seated at neutral, and seated at 30°-30°-30°) were evaluated in 181 individuals using hand-held dynamometry. Three separate 3-factor (limb by position by gender) analyses of variance were conducted on internal rotation, external rotation, and unilateral ratios. Although the dominant limb was significantly stronger (P < .001) than the nondominant for internal rotation, there was no difference for external rotation. The external rotators demonstrated significantly greater strength in the prone at 90° position compared with the seated at neutral (P = .001) and seated at 30°-30°-30° (P = .002) positions. The internal rotators demonstrated significantly greater (P = .036) strength in the neutral position than in the prone at 90° position for the women. The unilateral ratio of external rotators/internal rotators ranged from 86% to 99%. For the women, the prone at 90° ratio was significantly greater than seated at neutral (P = .001) and seated at 30°-30°-30° (P = .001) positions. Moderate strength relationships (r = 0.506 to 0.572) were revealed between body mass and all strength measures. The results of this study provide evidence to interpret normative data, bilateral comparisons and unilateral ratios of the internal/external rotators in the 3 selected positions. Because there are no differences between the seated at neutral and 30°-30°-30�

Water vapor isotopic measurements from the Atmospheric Radiation Measurement site on Graciosa Island, Azores

NASA Astrophysics Data System (ADS)

Delp, J. M.; Galewsky, J.

2017-12-01

Stable isotopic measurements of water vapor can potentially constrain the processes that govern the formation of low-clouds and how their distribution may change as the climate warms. Using off-axis integrated cavity output spectroscopy, in-situ water vapor isotopic measurements will be collected for a period of one year (beginning August 2017) at the US Department of Energy (DOE) Atmospheric Radiation Measurement (ARM) site in the Eastern North Atlantic (ENA) located on Graciosa Island, Azores. The Azores location within the ENA is a prime setting for studying low-cloud processes. After correcting for humidity-dependent biases and normalizing the measurements to the VSMOW-SLAP scale, the measurements from the first several months of the water vapor isotopic analyzer's deployment will be compared to complementary datasets from the suite of instruments at the DOE site, including twice-daily soundings, aerosol instrumentation, and cloud radars, with the purpose of determining links between local stratocumulus and precipitation processes and their impact on the stable isotopic composition of atmospheric water vapor. The results of this study will potentially provide a new approach for linking field observations with climate models and may help better constrain the uncertainties associated with low-cloud feedbacks.

SRS-sensor 13C/12C isotops measurements for detecting Helicobacter Pylori

NASA Astrophysics Data System (ADS)

Grishkanich, Aleksandr; Chubchenko, Yan; Elizarov, Valentin; Zhevlakov, Aleksandr; Konopelko, Leonid

2018-02-01

We developed SRS-sensor 13C/12C isotops measurements detecting Helicobacter Pylori for medical diagnostics of human health. Measuring of absolute 13C/12C isotope amount ratios allows to explore the topical problems of the modern world, alcoholic beverages and tobacco, medical diagnostics of human health. SRS method is used to measure the ratio of carbon isotopes in the exhaled carbon dioxide, which is used to diagnose the human infection of Helicobacter pylori and the influence of the Helicobacter pylori bacterium on the occurrence of gastritis, gastric and duodenal ulcers. A method for the analysis of human infection with Helicobacter pylori was developed on the basis of measurements of the ratio of 13C / 12C carbon isotopes in human exhaled air with a high level of measurement accuracy. The article reviews the work in the field of provision comparability of absolute 13C/12C isotope amount ratios in the environment and food. The analysis of the technical and metrological characteristics of traditional and perspective instruments for measuring isotope ratios is presented. The provision of comparability of absolute 13C/12C isotope amount ratios is carried by gravimetrically prepared reference standards. The key features and emerging issues are discussed.

Carbon Isotope Measurements of Experimentally-Derived Hydrothermal Mineral-Catalyzed Organic Products by Pyrolysis-Isotope Ratio Mass Spectrometry

NASA Technical Reports Server (NTRS)

Socki, Richard A.; Fu, Qi; Niles, Paul B.

2011-01-01

We report results of experiments to measure the C isotope composition of mineral catalyzed organic compounds derived from high temperature and high pressure synthesis. These experiments make use of an innovative pyrolysis technique designed to extract and measure C isotopes. To date, our experiments have focused on the pyrolysis and C isotope ratio measurements of low-molecular weight intermediary hydrocarbons (organic acids and alcohols) and serve as a proof of concept for making C and H isotope measurements on more complicated mixtures of solid-phase hydrocarbons and intermediary products produced during high temperature and high pressure synthesis on mineral-catalyzed surfaces. The impetus for this work stems from recently reported observations of methane detected within the Martian atmosphere [1-4], coupled with evidence showing extensive water-rock interaction during Martian history [5-7]. Methane production on Mars could be the result of synthesis by mineral surface-catalyzed reduction of CO2 and/or CO by Fischer-Tropsch Type (FTT) reactions during serpentization reactions [8,9]. Others have conducted experimental studies to show that FTT reactions are plausible mechanisms for low-molecular weight hydrocarbon formation in hydrothermal systems at mid-ocean ridges [10-12]. Further, recent experiments by Fu et al. [13] focus on examining detailed C isotope measurements of hydrocarbons produced by surface-catalyzed mineral reactions. Work described in this paper details the experimental techniques used to measure intermediary organic reaction products (alcohols and organic acids).

Measurement of isotope ratios on transient signals by MC-ICP-MS.

PubMed

Günther-Leopold, Ines; Wernli, Beat; Kopajtic, Zlatko; Günther, Detlef

2004-01-01

Precise and accurate isotope ratio measurements are an important task in many applications such as isotope-dilution mass spectrometry, bioavailability studies, or the determination of isotope variations in geological or nuclear samples. The technique of MC-ICP-MS has attracted much attention because it permits the precise measurement of isotope compositions for a wide range of elements combined with excellent detection limits due to high ionisation efficiencies. However, the results are based mainly on measurements using continuous sample introduction. In the present study the determination of isotope ratios on various transient signals with a time duration of 30 to 60 s has been achieved by coupling high-performance liquid chromatography to a multicollector inductively coupled plasma mass spectrometer. In order to investigate the origin of ratio drifts across the transient signals for this hyphenated technique, measurements with the same standard solutions were also carried out using a flow-injection device for sample introduction. As a result of this application it could be concluded that the main source of the bias in the measured isotope ratios is within the ICP-MS instead of fractionation effects on the chromatographic column material. Preliminary studies on short transient signals of gaseous samples (dry plasma) showed a reverse fractionation effect compared with wet plasma conditions (flow injection and HPLC).

MG Isotopic Measurement of FIB-Isolated Presolar Silicate Grains

NASA Technical Reports Server (NTRS)

Messenger, Scott R.; Nguyen, A.; Ito, M.; Rahman, Z.

2010-01-01

The majority of presolar oxide and silicate grains are ascribed to origins in low-mass red giant and asymptotic giant branch (AGB) stars based on their O isotopic ratios. However, a minor population of these grains (< 10%) has O isotopic ratios incompatible with these sources. Two principle alternative sources are higher-than-solar metallicity (Z) stars or, more likely, supernovae (SN) [1-3]. These rare (Group 4) grains [3] are characterized by enrichments in O-18, and typically also enrichments in O-17. An even rarer subset of grains with extremely large enrichments in O-17 and smaller depletions in O-18 were suggested to come from binary star systems [2]. To establish the origins of these isotopically unusual grains, it is necessary to examine isotopic systems in addition to O. Presolar silicates offer several elements diagnostic of their stellar sources and nuclear processes, including O, Si, Mg, Fe and Ca. However, the database for minor element isotopic compositions in silicates is seriously lacking. To date only two silicate grains have been analyzed for Mg [4] or Fe [5]. One major complicating factor is their small size (average 230 nm), which greatly limits the number of measurements that can be performed on any one grain and makes it more difficult to obtain statistically relevant data. This problem is compounded because the grains are identified among isotopically solar silicates, which contribute a diluting signal in isotopic measurements [1]. Thus, relatively small isotopic anomalies are missed due to this dilution effect. By applying focused ion beam (FIB) milling, we obtain undiluted Mg isotopic ratios of isolated rare presolar silicate grains to investigate their sources.

Patient-Reported Outcome Measures for Hand and Wrist Trauma

PubMed Central

Dacombe, Peter Jonathan; Amirfeyz, Rouin; Davis, Tim

2016-01-01

Background: Patient-reported outcome measures (PROMs) are important tools for assessing outcomes following injuries to the hand and wrist. Many commonly used PROMs have no evidence of reliability, validity, and responsiveness in a hand and wrist trauma population. This systematic review examines the PROMs used in the assessment of hand and wrist trauma patients, and the evidence for reliability, validity, and responsiveness of each measure in this population. Methods: A systematic review of Pubmed, Medline, and CINAHL searching for randomized controlled trials of patients with traumatic injuries to the hand and wrist was carried out to identify the PROMs. For each identified PROM, evidence of reliability, validity, and responsiveness was identified using a further systematic review of the Pubmed, Medline, CINAHL, and reverse citation trail audit procedure. Results: The PROM used most often was the Disabilities of the Arm, Shoulder and Hand (DASH) questionnaire; the Patient-Rated Wrist Evaluation (PRWE), Gartland and Werley score, Michigan Hand Outcomes score, Mayo Wrist Score, and Short Form 36 were also commonly used. Only the DASH and PRWE have evidence of reliability, validity, and responsiveness in patients with traumatic injuries to the hand and wrist; other measures either have incomplete evidence or evidence gathered in a nontraumatic population. Conclusions: The DASH and PRWE both have evidence of reliability, validity, and responsiveness in a hand and wrist trauma population. Other PROMs used to assess hand and wrist trauma patients do not. This should be considered when selecting a PROM for patients with traumatic hand and wrist pathology. PMID:27418884

Water vapor isotopes measurements at Mauna Loa, Hawaii: Comparison of laser spectroscopy and remote sensing with traditional methods, and the need for ongoing monitoring

NASA Astrophysics Data System (ADS)

Noone, D.; Galewsky, J.; Sharp, Z.; Worden, J.

2008-12-01

The isotopic composition of water vapor (2H/1H and 18O/16 ratios) provides unique information on the transport pathways that link the water sources to regional sinks, and thus proves useful in understanding the large scale humidity budgets. Recent advances in measurement technology allow the monitoring of water vapor isotope composition in ways which has can revolutionize investigations of atmospheric hydrology. Traditional measurement of isotopic composition requires trapping of samples with either large volume vacuum flasks or by trapping liquid samples with cryogens for later analyses using mass spectrometry, and are laborious and seldom span more than just short dedicated observational periods. On the other hand, laser absorption spectroscopy can provide almost continuous and autonomous in situ measurements of isotope abundances with precision almost that of traditional mass spectrometry, and observations from spacecraft can make almost daily maps of the global isotope distributions. In October of 2008 three laser based spectrometers were deployed at the Mauna Loa Laboratory in Hawaii to make continuous measurement of the 2H and 18O abundance of free tropospheric water vapor. These results are compared with traditional measurements and with measurements from two satellite platforms. While providing field validation of the new methodologies, the data show variability which captures the transport processes in the region. The data are used to characterize the role of large scale mixing of dry air, the influence of the boundary layer and the importance of moist convection in controlling the low humidity of subtropical air near Hawaii. Although the record is short, it demonstrates the usefulness of using robust isotope measurements to understand the budgets of the most important greenhouse gas. This work motivates establishing a continuous record of isotopes measurement at baseline sites, like Mauna Loa, such that the changes in water cycle can be understood and

Water vapor isotopes measurements at Mauna Loa, Hawaii: Comparison of laser spectroscopy and remote sensing with traditional methods, and the need for ongoing monitoring

NASA Astrophysics Data System (ADS)

Galewsky, J.; Noone, D.; Sharp, Z.; Worden, J.

2009-04-01

The isotopic composition of water vapor (2H/1H and 18O/16 ratios) provides unique information on the transport pathways that link water sources to regional sinks, and thus proves useful in understanding large scale atmospheric humidity budgets. Recent advances in measurement technology allow the monitoring of water vapor isotope composition in ways which has can revolutionize investigations of atmospheric hydrology. Traditional measurement of isotopic composition requires trapping of samples with either large volume vacuum flasks or by trapping liquid samples with cryogens for later analyses using mass spectrometry, and are laborious and seldom span more than just short dedicated observational periods. On the other hand, laser absorption spectroscopy can provide almost continuous and autonomous in situ measurements of isotope abundances with precision almost that of traditional mass spectrometry, and observations from spacecraft can make almost daily maps of the global isotope distributions. In October of 2008 three laser based spectrometers were deployed at the Mauna Loa Laboratory in Hawaii to make continuous measurement of the 2H and 18O abundance of free tropospheric water vapor. These results are compared with traditional measurements and with measurements from two satellite platforms. While providing field validation of the new methodologies, the data show variability which captures the transport processes in the region. The data are used to characterize the role of large scale mixing of dry air, the influence of the boundary layer and the importance of moist convection in controlling the low humidity of subtropical air near Hawaii. Although the record is short, it demonstrates the usefulness of using robust isotope measurements to understand the budgets of the most important greenhouse gas. This work motivates establishing a continuous record of isotopes measurement at baseline sites, like Mauna Loa, such that the changes in water cycle can be understood and

Measurement of isotope ratio of Ca{sup +} ions in a linear Paul Trap

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hashimoto, Y.; Minamino, K.; Nagamoto, D.

2009-03-17

Measurement of isotope ratios of Calcium is very useful in many fields. So we demonstrated the measurement of isotope ratios of {sup 40}Ca{sup +}(abundance 96.4%) to {sup 44}Ca{sup +}(2.09%) ions in a linear Paul trap with several laser lights tuning to the isotope shifts. And we found that the experimental parameters had large influences on the measurement of the isotope ratios.

Hands beat machines for collecting native seed

Treesearch

Mary Ann Davies; Scott Jensen

2008-01-01

A hedge trimmer (Garden Groom Pro) and a hand-held vacuum (Euro-Pro Shark) were tested to determine whether they might be more effective for collecting the seed of native plants than common hand methods. The common hand methods worked best.

Hands-on Science. Exploring Magnification.

ERIC Educational Resources Information Center

Kepler, Lynne

1993-01-01

Presents hands-on science activities using inexpensive, hand-held microscopes and slides made from simple, readily available materials. The article describes how to introduce students to microscopes and presents directions for using the microscopes and making slides. A student page investigates fingerprints with microscopes. (SM)

Method to make accurate concentration and isotopic measurements for small gas samples

NASA Astrophysics Data System (ADS)

Palmer, M. R.; Wahl, E.; Cunningham, K. L.

2013-12-01

Carbon isotopic ratio measurements of CO2 and CH4 provide valuable insight into carbon cycle processes. However, many of these studies, like soil gas, soil flux, and water head space experiments, provide very small gas sample volumes, too small for direct measurement by current constant-flow Cavity Ring-Down (CRDS) isotopic analyzers. Previously, we addressed this issue by developing a sample introduction module which enabled the isotopic ratio measurement of 40ml samples or smaller. However, the system, called the Small Sample Isotope Module (SSIM), does dilute the sample during the delivery with inert carrier gas which causes a ~5% reduction in concentration. The isotopic ratio measurements are not affected by this small dilution, but researchers are naturally interested accurate concentration measurements. We present the accuracy and precision of a new method of using this delivery module which we call 'double injection.' Two portions of the 40ml of the sample (20ml each) are introduced to the analyzer, the first injection of which flushes out the diluting gas and the second injection is measured. The accuracy of this new method is demonstrated by comparing the concentration and isotopic ratio measurements for a gas sampled directly and that same gas measured through the SSIM. The data show that the CO2 concentration measurements were the same within instrument precision. The isotopic ratio precision (1σ) of repeated measurements was 0.16 permil for CO2 and 1.15 permil for CH4 at ambient concentrations. This new method provides a significant enhancement in the information provided by small samples.

Hand-Held Femtogram Detection of Hazardous Picric Acid with Hydrophobic Ag Nanopillar SERS Substrates and Mechanism of Elasto-Capillarity.

PubMed

Hakonen, Aron; Wang, FengChao; Andersson, Per Ola; Wingfors, Håkan; Rindzevicius, Tomas; Schmidt, Michael Stenbæk; Soma, Venugopal Rao; Xu, Shicai; Li, YingQi; Boisen, Anja; Wu, HengAn

2017-02-24

Picric acid (PA) is a severe environmental and security risk due to its unstable, toxic, and explosive properties. It is also challenging to detect in trace amounts and in situ because of its highly acidic and anionic character. Here, we assess sensing of PA under nonlaboratory conditions using surface-enhanced Raman scattering (SERS) silver nanopillar substrates and hand-held Raman spectroscopy equipment. The advancing elasto-capillarity effects are explained by molecular dynamics simulations. We obtain a SERS PA detection limit on the order of 20 ppt, corresponding attomole amounts, which together with the simple analysis methodology demonstrates that the presented approach is highly competitive for ultrasensitive analysis in the field.

Comparison of exhalation time methods (6 sec vs. 10 sec) of a hand-held exhaled nitric oxide analyzer.

PubMed

Ito, Yasunori; Adachi, Yuichi; Itazawa, Toshiko; Okabe, Yoshie; Adachi, Yoko S; Katsumuma, Toshio; Miyawaki, Toshio

2010-10-01

Standard exhalation time for measuring fractional exhaled nitric oxide (FeNO) is 10 sec, but this is not easy for younger children. We aimed to investigate the agreement between FeNO values during 10-sec (FeNO-10) and 6-sec (FeNO-6) exhalation and the feasibility of measuring FeNO-6, using a hand-held analyzer, NIOX-MINO®. FeNO values measured during 10- and 6-sec (random order) were compared. Success rates of the two different time modes were also evaluated. In 119 asthmatic children (median age 8 years [range 4-15]) who had been already accustomed to NIOX-MINO®, median FeNO-10 (29 ppb [IQR 15.2-42.0]) and FeNO-6 (27 ppb [IQR 16.0-43.5]) did not differ significantly (P = 0.90), and there was a good correlation between both values (r = 0.984, P < 0.001). Mean difference (FeNO-10-FeNO-6) was -0.151 ppb (95% CI: -0.95 to 0.65, limits of agreement: -8.8 to 8.5). In 46 asthmatic children (median age 7 years [range 4-15]) who had never used any FeNO analyzers, all the children aged 8 years and more (n = 21) succeeded in measuring FeNO on both time modes, whereas for children aged younger than 8 years (n = 25) success rates of the 10- and 6-sec mode were 60.0% and 92.0%, respectively. In conclusion, we showed good agreement between FeNO-10 and FeNO-6, and the 6-sec mode of NIOX-MINO® is more feasible than 10-sec mode for measuring FeNO in younger children. © 2010 Wiley-Liss, Inc.

New reference materials for nitrogen-isotope-ratio measurements

USGS Publications Warehouse

Böhlke, John Karl; Gwinn, C. J.; Coplen, T. B.

1993-01-01

Three new reference materials were manufactured for calibration of relative stable nitrogen-isotope-ratio measurements: USGS25 (ammonium sulfate) d15N' = -30 per mil; USGS26 (ammonium sulfate) d15N' = +54 per mil; USGS32 (potassium nitrate) d15N' = +180 per mil, where d15N', relative to atmospheric nitrogen, is an approximate value subject to change following interlaboratory comparisons. These materials are isotopically homogeneous in aliquots at least as small as 10 µmol N2 (or about 1-2 mg of salt). The new reference materials greatly extend the range of d15N values of internationally distributed standards, and they allow normalization of d15N measurements over almost the full range of known natural isotope variation on Earth. The methods used to produce these materials may be adapted to produce homogeneous local laboratory standards for routine use.

High precision isotope ratio measurements of mercury isotopes in cinnabar ores using multi-collector inductively coupled plasma mass spectrometry.

PubMed

Hintelmann, Holger; Lu, ShengYong

2003-06-01

Variations in Hg isotope ratios in cinnabar ores obtained from different countries were detected by high precision isotope ratio measurements using multi-collector inductively coupled mass spectrometry (MC-ICP-MS). Values of delta198/202Hg varied from 0.0-1.3 percent per thousand relative to a NIST SRM 1641d Hg solution. The typical external uncertainty of the delta values was 0.06 to 0.26 percent per thousand. Hg was introduced into the plasma as elemental Hg after reduction by sodium borohydride. A significant fractionation of lead isotopes was observed during the simultaneous generation of lead hydride, preventing normalization of the Hg isotope ratios using the measured 208/206Pb ratio. Hg ratios were instead corrected employing the simultaneously measured 205/203T1 ratio. Using a 10 ng ml(-1) Hg solution and 10 min of sampling, introducing 60 ng of Hg, the internal precision of the isotope ratio measurements was as low as 14 ppm. Absolute Hg ratios deviated from the representative IUPAC values by approximately 0.2% per u. This observation is explained by the inadequacy of the exponential law to correct for mass bias in MC-ICP-MS measurements. In the absence of a precisely characterized Hg isotope ratio standard, we were not able to determine unambiguously the absolute Hg ratios of the ore samples, highlighting the urgent need for certified standard materials.

21 CFR 872.4565 - Dental hand instrument.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Dental hand instrument. 872.4565 Section 872.4565...) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4565 Dental hand instrument. (a) Identification. A dental hand instrument is a hand-held device intended to perform various tasks in general dentistry and...

21 CFR 872.4565 - Dental hand instrument.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Dental hand instrument. 872.4565 Section 872.4565...) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4565 Dental hand instrument. (a) Identification. A dental hand instrument is a hand-held device intended to perform various tasks in general dentistry and...

21 CFR 872.4565 - Dental hand instrument.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Dental hand instrument. 872.4565 Section 872.4565...) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4565 Dental hand instrument. (a) Identification. A dental hand instrument is a hand-held device intended to perform various tasks in general dentistry and...

21 CFR 872.4565 - Dental hand instrument.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Dental hand instrument. 872.4565 Section 872.4565...) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4565 Dental hand instrument. (a) Identification. A dental hand instrument is a hand-held device intended to perform various tasks in general dentistry and...

21 CFR 872.4565 - Dental hand instrument.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Dental hand instrument. 872.4565 Section 872.4565...) MEDICAL DEVICES DENTAL DEVICES Surgical Devices § 872.4565 Dental hand instrument. (a) Identification. A dental hand instrument is a hand-held device intended to perform various tasks in general dentistry and...

Isotopic Ratios in Titan's Methane: Measurements and Modeling

NASA Technical Reports Server (NTRS)

Nixon, C. A.; Temelso, B.; Vinatier, S.; Teanby, N. A.; Bezard, B.; Achterberg, R. K.; Mandt, K. E.; Sherrill, C. D.; Irwin, P. G.; Jennings, D. E.;

DANCEing with the Stars: Measuring Neutron Capture on Unstable Isotopes with DANCE

DOE Office of Scientific and Technical Information (OSTI.GOV)

Couture, A.; Bond, E.; Bredeweg, T. A.

2009-03-10

Isotopes heavier than iron are known to be produced in stars through neutron capture processes. Two major processes, the slow (s) and rapid (r) processes are each responsible for 50% of the abundances of the heavy isotopes. The neutron capture cross sections of the isotopes on the s process path reveal information about the expected abundances of the elements as well as stellar conditions and dynamics. Until recently, measurements on unstable isotopes, which are most important for determining stellar temperatures and reaction flow, have not been experimentally feasible. The Detector for Advance Neutron Capture Experiments (DANCE) located at the Losmore » Alamos Neutron Science Center (LANSCE) was designed to perform time-of-flight neutron capture measurements on unstable isotopes for nuclear astrophysics, stockpile stewardship, and reactor development. DANCE is a 4-{pi}BaF{sub 2} scintillator array which can perform measurements on sub-milligram samples of isotopes with half-lives as short as a few hundred days. These cross sections are critical for advancing our understanding of the production of the heavy isotopes.« less

[Hand hygiene: first measure to control nosocomial infection].

PubMed

Christiaens, G; Barbier, C; Mutsers, J; Warnotte, J; De Mol, P; Bouffioux, C

2006-01-01

Hand hygiene prevents cross infection in hospi tals, however adherence to guidelines is commonly poor. The hand-hygiene promotion programme started on May 2004 at the University Hospital of Liège after a baseline survey of compliance. We attempted to promote hand hygiene and most par ticularly alcohol-based hand disinfection. We measured MRSA transmission rates and consumption of alcohol-based handrub solution and soap in parallel. During the campaign, consump tion of alcohol-based handrub solution and soap increased by 56% and 24% respectively and MRSA transmission rates decreased from 11,04 to 7,07 cases per 1000 admissions.

Preliminary results of oxygen isotope ratio measurement with a particle-gamma coincidence method

NASA Astrophysics Data System (ADS)

Borysiuk, Maciek; Kristiansson, Per; Ros, Linus; Abdel, Nassem S.; Elfman, Mikael; Nilsson, Charlotta; Pallon, Jan

2015-04-01

The possibility to study variations in the oxygen isotopic ratio with photon tagged nuclear reaction analysis (pNRA) is evaluated in the current work. The experiment described in the article was performed at Lund Ion Beam Analysis Facility (LIBAF) with a 2 MeV deuteron beam. Isotopic fractionation of light elements such as carbon, oxygen and nitrogen is the basis of many analytical tools in hydrology, geology, paleobiology and paleogeology. IBA methods provide one possible tool for measurement of isotopic content. During this experimental run we focused on measurement of the oxygen isotopic ratio. The measurement of stable isotopes of oxygen has a number of applications; the particular one driving the current investigation belongs to the field of astrogeology and specifically evaluation of fossil extraterrestrial material. There are three stable isotopes of oxygen: 16O, 17O and 18O. We procured samples highly enriched with all three isotopes. Isotopes 16O and 18O were easily detected in the enriched samples, but no significant signal from 17O was detected in the same samples. The measured yield was too low to detect 18O in a sample with natural abundances of oxygen isotopes, at least in the current experimental setup, but the spectral line from the reaction with 16O was clearly visible.

Hand involvement in children with Charcot-Marie-Tooth disease type 1A.

PubMed

Burns, Joshua; Bray, Paula; Cross, Lauren A; North, Kathryn N; Ryan, Monique M; Ouvrier, Robert A

2008-12-01

Charcot-Marie-Tooth disease type 1A (CMT1A), a demyelinating neuropathy characterised by progressive length-dependent muscle weakness and atrophy, is thought to affect the foot and leg first followed some time later by hand weakness and dysfunction. We aimed to characterise hand strength, function and disease-related symptoms in children with CMT1A. Intrinsic and extrinsic hand strength was measured by hand-held dynamometry, function by nine-hole peg test, and disease-related symptoms by interview and examination in 84 affected children aged 2-16 years. Hand weakness and dysfunction was present from the earliest stages of the disease. While hand strength and function measures tended to increase with age throughout childhood, at no point did they reach normal values. Day-to-day hand problems such as poor handwriting, weakness, pain and sensory symptoms also worsened with age. The hand is affected at all ages in children with CMT1A, but may be under-recognised in its early stages, potentially delaying therapy.

Absolute Isotopic Abundance Ratios and the Accuracy of Δ47 Measurements

NASA Astrophysics Data System (ADS)

Daeron, M.; Blamart, D.; Peral, M.; Affek, H. P.

2016-12-01

Conversion from raw IRMS data to clumped isotope anomalies in CO2 (Δ47) relies on four external parameters: the (13C/12C) ratio of VPDB, the (17O/16O) and (18O/16O) ratios of VSMOW (or VPDB-CO2), and the slope of the triple oxygen isotope line (λ). Here we investigate the influence that these isotopic parameters exert on measured Δ47 values, using real-world data corresponding to 7 months of measurements; simulations based on randomly generated data; precise comparisons between water-equilibrated CO2 samples and between carbonate standards believed to share quasi-identical Δ47 values; reprocessing of two carbonate calibration data sets with different slopes of Δ47 versus T. Using different sets of isotopic parameters generally produces systematic offsets as large as 0.04 ‰ in final Δ47 values. What's more, even using a single set of isotopic parameters can produce intra- and inter-laboratory discrepancies in final Δ47 values, if some of these parameters are inaccurate. Depending on the isotopic compositions of the standards used for conversion to "absolute" values, these errors should correlate strongly with either δ13C or δ18O, or more weakly with both. Based on measurements of samples expected to display identical Δ47 values, such as 25°C water-equilibrated CO2 with different carbon and oxygen isotope compositions, or high-temperature standards ETH-1 and ETH-2, we conclude that the isotopic parameters used so far in most clumped isotope studies produces large, systematic errors controlled by the relative bulk isotopic compositions of samples and standards, which should be one of the key factors responsible for current inter-laboratory discrepancies. By contrast, the isotopic parameters of Brand et al. [2010] appear to yield accurate Δ47 values regardless of bulk isotopic composition. References:Brand, Assonov and Coplen [2010] http://dx.doi.org/10.1351/PAC-REP-09-01-05

Sulphur isotope applications in two Philippine geothermal systems

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bayon, F.E.B.

1996-12-31

A general and very preliminary study of sulphur isotope geochemistry is presented in this paper. Data from the Mt. Apo and Palinpinon geothermal fields are used to demonstrate the use of sulphur isotopes in geothermometry and correlation of sulphur species. Sulphur and oxygen isotope geothermometers applied to Mt. Apo data show very good agreement with temperatures estimated using other established geothermometers, as well as bore measured temperatures. This signifies that sulphur isotopes in S-species in fluids of the Mt. Apo hydrothermal system are in equilibrium at drilled depths. In Palinpinon, on the other hand, temperature estimates from fluid and mineralmore » sulphur isotope geothermometry calculations do not agree with, and are commonly higher than, well measured temperatures and temperatures estimated from other geothermometers. Sulphur isotopes in the presently-exploited Palinpinon fluid are not in equilibrium, and sulphur isotope geothermometry may be reflective of isotopic equilibrium of the deeper portions of the hydrothermal system. Dissolved sulphate in both the Palinpinon and Mt. Apo geothermal fluids appear to originate from the disproportionation of magmatic SO{sub 2} at temperatures below 400{degrees}C. Hydrogen sulphide in well discharge fluids are dominantly directly derived from the magma, with a minor amount coming from SO{sub 2} disproportionation.« less

Development of a high-speed VCSEL OCT system for real-time imaging of conscious patients larynx using a hand-held probe (Conference Presentation)

NASA Astrophysics Data System (ADS)

Rangarajan, Swathi; Chou, Li-Dek; Coughlan, Carolyn; Sharma, Giriraj; Wong, Brian J. F.; Ramalingam, Tirunelveli S.

2016-02-01

Fourier domain optical coherence tomography (FD-OCT) is a noninvasive imaging modality that has previously been used to image the human larynx. However, differences in anatomical geometry and short imaging range of conventional OCT limits its application in a clinical setting. In order to address this issue, we have developed a gradient-index (GRIN) lens rod-based hand-held probe in conjunction with a long imaging range 200 kHz Vertical-Cavity Surface Emitting Lasers (VCSEL) swept-source optical coherence tomography (SS-OCT) system for high speed real-time imaging of the human larynx in an office setting. This hand-held probe is designed to have a long and dynamically tunable working distance to accommodate the differences in anatomical geometry of human test subjects. A nominal working distance (~6 cm) of the probe is selected to have a lateral resolution <100 um within a depth of focus of 6.4 mm, which covers more than half of the 12 mm imaging range of the VCSEL laser. The maximum lateral scanning range of the probe at 6 cm working distance is approximately 8.4 mm, and imaging an area of 8.5 mm by 8.5 mm is accomplished within a second. Using the above system, we will demonstrate real-time cross-sectional OCT imaging of larynx during phonation in vivo in human and ex-vivo in pig vocal folds.

Landscape Evolution Mechanisms in Gale Crater from In-Situ Measurement of Cosmogenic Noble Gas Isotopes

NASA Astrophysics Data System (ADS)

Martin, P.; Farley, K. A.; Mahaffy, P. R.; Malespin, C.; Vasconcelos, P. M.

2017-12-01

The Sample Analysis at Mars (SAM) instrument onboard the Curiosity rover can measure the noble gas isotopes contained in drilled rock samples on Mars by heating these samples to 930°C. In combination with bulk chemistry measured by the Alpha Particle X-ray Spectrometer (APXS), cosmogenic nuclide production rates can be determined and an exposure age may be calculated. Three cosmogenic nuclides are measured: 3He, and 21Ne, which are produced via spallation of mainly O, Mg, Si, and Al (held mostly in detrital grains); and 36Ar, which is produced from neutron capture of 35Cl (held mostly in secondary materials). To date, three samples have been measured: Cumberland (CB), Windjana (WJ), and Mojave 2 (MJ2). CB yielded 3He, 21Ne, and 36Ar ages of 72 ± 15, 84 ± 28, and 79 ± 24 Ma, respectively [Farley et al., 2014]. Two aliquots of WJ gave error-weighted mean ages of 30 ± 27 Ma (3He), 54 ± 19 Ma (21Ne), and 63 ± 84 Ma (36Ar) [Vasconcelos et al., 2016]. These relatively young ages were interpreted to suggest that a scarp-retreat mechanism is responsible for erosion at both the CB and WJ localities. The most recent measurements on MJ2 do not include the 21Ne isotope because of an instrument issue at this mass. 3He observed in MJ2 is the highest of any sample yet measured, suggesting an exposure age of approximately 1 Ga. In contrast, the calculated exposure age from 36Ar appears to be less than 100 Ma (despite a high uncertainty due to isobaric H35Cl). This discrepancy could be explained by 1) a contribution of extraterrestrial 3He from interplanetary dust or meteoritic fragments, or 2) approximately 1 Ga of prior exposure to the detrital grains. In the latter case 36Ar accumulates only after the Cl-bearing secondary minerals are formed and exposed at the surface. In either scenario the 36Ar measurement provides the better estimate of the recent exposure history. The young upper limit for 36Ar at MJ2 is consistent with the scarp-retreat mechanism observed at CB and

Performance evaluation of haptic hand-controllers in a robot-assisted surgical system.

PubMed

Zareinia, Kourosh; Maddahi, Yaser; Ng, Canaan; Sepehri, Nariman; Sutherland, Garnette R

2015-12-01

This paper presents the experimental evaluation of three commercially available haptic hand-controllers to evaluate which was more suitable to the participants. Two surgeons and seven engineers performed two peg-in-hole tasks with different levels of difficulty. Each operator guided the end-effector of a Kuka manipulator that held surgical forceps and was equipped with a surgical microscope. Sigma 7, HD(2) and PHANToM Premium 3.0 hand-controllers were compared. Ten measures were adopted to evaluate operators' performances with respect to effort, speed and accuracy in completing a task, operator improvement during the tests, and the force applied by each haptic device. The best performance was observed with the Premium 3.0; the hand-piece was able to be held in a similar way to that used by surgeons to hold conventional tools. Hand-controllers with a linkage structure similar to the human upper extremity take advantage of the inherent human brain connectome, resulting in improved surgeon performance during robotic-assisted surgery. Copyright © 2015 John Wiley & Sons, Ltd.

Measurement of natural carbon isotopic composition of acetone in human urine.

PubMed

Yamada, Keita; Ohishi, Kazuki; Gilbert, Alexis; Akasaka, Mai; Yoshida, Naohiro; Yoshimura, Ryoko

2016-02-01

The natural carbon isotopic composition of acetone in urine was measured in healthy subjects using gas chromatography-combustion-isotope ratio mass spectrometry combined with headspace solid-phase microextraction (HS-SPME-GC-C-IRMS). Before applying the technique to a urine sample, we optimized the measurement conditions of HS-SPME-GC-C-IRMS using aqueous solutions of commercial acetone reagents. The optimization enabled us to determine the carbon isotopic compositions within ±0.2 ‰ of precision and ±0.3‰ of error using 0.05 or 0.2 mL of aqueous solutions with acetone concentrations of 0.3-121 mg/L. For several days, we monitored the carbon isotopic compositions and concentrations of acetone in urine from three subjects who lived a daily life with no restrictions. We also monitored one subject for 3 days including a fasting period of 24 h. These results suggest that changes in the availability of glucose in the liver are reflected in changes in the carbon isotopic compositions of urine acetone. Results demonstrate that carbon isotopic measurement of metabolites in human biological samples at natural abundance levels has great potential as a tool for detecting metabolic changes caused by changes in physiological states and disease.

Experimental Artifacts in Nitrogen Isotope Measurements of Meteorites

NASA Astrophysics Data System (ADS)

Kim, J. S.; Marti, K.

1993-07-01

Several research groups have studied contamination problems and molecular interferences in nitrogen isotope measurements, but some problems still require clarification. Protocols adopted for nitrogen isotope measurements generally consider questions such as CO interference, removal of hydrocarbons, and N2O and NO conversion [1]. In the analysis of nanogram amounts of N, contamination, exchange reactions, and interferences are more visible than in large N samples. During nitrogen measurements we observed several potential problems and developed an improved protocol to achieve high-quality isotopic data: 1. Nitrogen loss and isotopic exchange were observed on the extraction system wall. The wall has active surfaces produced by vapor deposition (previous samples) that absorb many molecules, including nitrogen. This absorbed nitrogen releases or exchanges nitrogen with sample N in the following extraction steps. Therefore the losses need to be calibrated and the extent of isotopic exchange determined at the nanogram level. A continuous adsorption during sample extraction of the gas phase onto zeolite at liquid nitrogen temperature reduces nitrogen loss and amount of exchange. 2. We also found nitrogen isotopic memory effect by CuO. During sample gas cleaning by CuO, nitrogen exchanges with residual nitrogen in the CuO, and losses to CuO by solubility and/or uptake of nitrogen during oxygen uptake. This effect is clearly visible after analysis of large amounts of nitrogen. In such cases the CuO blank showed traces of previously measured isotopic signatures. Therefore, the isotopic signature of the CuO blank must be assessed before proceeding. 3. NO interference was recognized. In measurements of N in bulk H chondrites, the steps above 900 degrees C show anomalous contribution to the mass 30 peak, which decreases rapidly with time in the mass spectrometer. Using the ratio mass 30 to mass 31 and the corresponding physical properties of the interfering compound, we

Comparison of non-invasive tear film stability measurement techniques.

PubMed

Wang, Michael Tm; Murphy, Paul J; Blades, Kenneth J; Craig, Jennifer P

2018-01-01

Measurement of tear film stability is commonly used to give an indication of tear film quality but a number of non-invasive techniques exists within the clinical setting. This study sought to compare three non-invasive tear film stability measurement techniques: instrument-mounted wide-field white light clinical interferometry, instrument-mounted keratoscopy and hand-held keratoscopy. Twenty-two subjects were recruited in a prospective, randomised, masked, cross-over study. Tear film break-up or thinning time was measured non-invasively by independent experienced examiners, with each of the three devices, in a randomised order, within an hour. Significant correlation was observed between instrument-mounted interferometric and keratoscopic measurements (p < 0.001) but not between the hand-held device and the instrument-mounted techniques (all p > 0.05). Tear film stability values obtained from the hand-held device were significantly shorter and demonstrated narrower spread than the other two instruments (all p < 0.05), while no significant differences were observed between the two instrument-mounted devices (all p > 0.05). Good clinical agreement exists between the instrument-mounted interferometric and keratoscopic measurements but not between the hand-held device and either of the instrument-mounted techniques. The results highlight the importance of specifying the instrument employed to record non-invasive tear film stability. © 2017 Optometry Australia.

Automation Study for Longhorn Army Ammunition Plant Hand Held Signal Flight Assembly, Rocket Barrel Assembly, 40 MM Signal, Final Packaging/Pack-Out, and Star Finishing

DTIC Science & Technology

1990-03-01

J.B. Webb Jonesboro , AR Farmington, MI Crimping Press Joraco Drake Corp. Smithfield, RI Phoenix, AZ Die Cutter Roll Cut Peerless Machinery Co. Harbour...be taken are detailed for each assembly procedure. The report provides overall system integration requirements. The layouts of the two manufacturing...buildings are detailed. Several component changes to the Hand Held Signals are proposed. None of these will affect the operation of the-final product

Natural isotope correction of MS/MS measurements for metabolomics and (13)C fluxomics.

PubMed

Niedenführ, Sebastian; ten Pierick, Angela; van Dam, Patricia T N; Suarez-Mendez, Camilo A; Nöh, Katharina; Wahl, S Aljoscha

2016-05-01

Fluxomics and metabolomics are crucial tools for metabolic engineering and biomedical analysis to determine the in vivo cellular state. Especially, the application of (13)C isotopes allows comprehensive insights into the functional operation of cellular metabolism. Compared to single MS, tandem mass spectrometry (MS/MS) provides more detailed and accurate measurements of the metabolite enrichment patterns (tandem mass isotopomers), increasing the accuracy of metabolite concentration measurements and metabolic flux estimation. MS-type data from isotope labeling experiments is biased by naturally occurring stable isotopes (C, H, N, O, etc.). In particular, GC-MS(/MS) requires derivatization for the usually non-volatile intracellular metabolites introducing additional natural isotopes leading to measurements that do not directly represent the carbon labeling distribution. To make full use of LC- and GC-MS/MS mass isotopomer measurements, the influence of natural isotopes has to be eliminated (corrected). Our correction approach is analyzed for the two most common applications; (13)C fluxomics and isotope dilution mass spectrometry (IDMS) based metabolomics. Natural isotopes can have an impact on the calculated flux distribution which strongly depends on the substrate labeling and the actual flux distribution. Second, we show that in IDMS based metabolomics natural isotopes lead to underestimated concentrations that can and should be corrected with a nonlinear calibration. Our simulations indicate that the correction for natural abundance in isotope based fluxomics and quantitative metabolomics is essential for correct data interpretation. © 2015 Wiley Periodicals, Inc.

Electric Dipole Moment Measurements with Rare Isotopes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chupp, Timothy

The origin of matter is one of the deepest questions addressed by science and remains a mystery because our understanding of the Big Bang suggests that equal amounts of matter as antimatter would be created and annihilate leaving nothing from which stars, galaxies, planets and ultimately life as we know it was created. We know this is not the case in the universe, and so the explanation that the laws of physics can distinguish the difference of moving forward and backward in time and provide mechanisms that produce more matter that antimatter so that a little bit was left over.more » These same laws of physics affect our world today and would very slightly change the shape of an atom, stretching is along the direction of the spin of its nucleus. This subtle shape change has been searched in many systems - the neutron, atoms and molecules, but has not yet been detected, even as the motivation is strengthened by our understanding of their structure. We therefore look to new systems that have special features that make these effects stand out. Rare isotopes provide one possibility and specific radon atoms are our choice. We have developed techniques to make these measurements with short-lived radioactive atoms, studied the nuclei to provide deeper understanding of how these affect arise in such atoms (including radium) and developed new laser-based techniques to measure and control the magnetic fields necessary to perform these exquisitely sensitive measurements. In this work we have shown that radioactive radon atoms can be produced and transported to an apparatus that lines up the spins of the atoms. We have also shown that the nuclei of nearby radium are pear shaped and that the radon nuclei likely oscillate from one pear shape to its mirror reflection. We have also used the techniques which control nuclear spin to study the magnetic environment in a magnetically shielded room, which has the smallest magnetic field in a large volume in the universe. Measuring

A Portable, Field-Deployable Analyzer for Isotopic Water Measurements

NASA Astrophysics Data System (ADS)

Berman, E. S.; Gupta, M.; Huang, Y. W.; Lacelle, D.; McKay, C. P.; Fortson, S.

2015-12-01

Water stable isotopes have for many years been used to study the hydrological cycle, catchment hydrology, and polar climate among other applications. Typically, discrete water samples are collected and transported to a laboratory for isotope analysis. Due to the expense and labor associated with such sampling, isotope studies have generally been limited in scope and time-resolution. Field sampling of water isotopes has been shown in recent years to provide dense data sets with the increased time resolution illuminating substantially greater short term variability than is generally observed during discrete sampling. A truly portable instrument also opens the possibility to utilize the instrument as a tool for identifying which water samples would be particularly interesting for further laboratory investigation. To make possible such field measurements of liquid water isotopes, Los Gatos Research has developed a miniaturized, field-deployable liquid water isotope analyzer. The prototype miniature liquid water isotope analyzer (mini-LWIA) uses LGR's patented Off-Axis ICOS (Integrated Cavity Output Spectroscopy) technology in a rugged, Pelican case housing for easy transport and field operations. The analyzer simultaneously measures both δ2H and δ18O from liquid water, with both manual and automatic water introduction options. The laboratory precision for δ2H is 0.6 ‰, and for δ18O is 0.3 ‰. The mini-LWIA was deployed in the high Arctic during the summer of 2015 at Inuvik in the Canadian Northwest Territories. Samples were collected from Sachs Harbor, on the southwest coast of Banks Island, including buried basal ice from the Lurentide Ice Sheet, some ice wedges, and other types of ground ice. Methodology and water analysis results from this extreme field deployment will be presented.

Do Right- and Left-Handed Monkeys Differ on Cognitive Measures?

NASA Technical Reports Server (NTRS)

Hopkins, William D.; Washburn, David A.

1994-01-01

Twelve left- and 14 right-handed monkeys were compared on 6 measures of cognitive performance (2 maze-solving tasks, matching-to-sample, delayed matching-to-sample, delayed response using spatial cues, and delayed response using form cues). The dependent variable was trials-to-training criterion for each of the 6 tasks. Significant differences were found between left- and right-handed monkeys on the 2 versions of the delayed response task. Right-handed monkeys reached criterion significantly faster on the form cue version of the task, whereas left-handed monkeys reached criterion significantly faster on delayed response for spatial position (p less than .05). The results suggest that sensitive hand preference measures of laterality can reveal differences in cognitive performance, which in turn may reflect underlying laterality in functional organization of the nervous system.

Validation of hand and foot anatomical feature measurements from smartphone images

NASA Astrophysics Data System (ADS)

Amini, Mohammad; Vasefi, Fartash; MacKinnon, Nicholas

2018-02-01

A smartphone mobile medical application, previously presented as a tool for individuals with hand arthritis to assess and monitor the progress of their disease, has been modified and expanded to include extraction of anatomical features from the hand (joint/finger width, and angulation) and foot (length, width, big toe angle, and arch height index) from smartphone camera images. Image processing algorithms and automated measurements were validated by performing tests on digital hand models, rigid plastic hand models, and real human hands and feet to determine accuracy and reproducibility compared to conventional measurement tools such as calipers, rulers, and goniometers. The mobile application was able to provide finger joint width measurements with accuracy better than 0.34 (+/-0.25) millimeters. Joint angulation measurement accuracy was better than 0.50 (+/-0.45) degrees. The automatically calculated foot length accuracy was 1.20 (+/-1.27) millimeters and the foot width accuracy was 1.93 (+/-1.92) millimeters. Hallux valgus angle (used in assessing bunions) accuracy was 1.30 (+/-1.29) degrees. Arch height index (AHI) measurements had an accuracy of 0.02 (+/-0.01). Combined with in-app documentation of symptoms, treatment, and lifestyle factors, the anatomical feature measurements can be used by both healthcare professionals and manufacturers. Applications include: diagnosing hand osteoarthritis; providing custom finger splint measurements; providing compression glove measurements for burn and lymphedema patients; determining foot dimensions for custom shoe sizing, insoles, orthotics, or foot splints; and assessing arch height index and bunion treatment effectiveness.

O-stable Isotopes Distribution In Deep-sea Corals From Sims Measurements

NASA Astrophysics Data System (ADS)

Blamart, D.; Cuif, J.-P.; Juillet-Leclerc, A.

Urey's theoretical calculations (Urey, 1947) have predicted that the O-isotope fraction- ations between calcium carbonates and water should be large enough to be used as a paleothermometer. However, stable isotopes studies on aragonitic invertebrates includ- ing corals have also demonstrated departure of several per mil from O-equilibrium. Different tentative explanations have been proposed in the literature: (1) influence of the polymorphism form and chemical composition of the calcium carbonate (2) kinetic effects related to calcification process during rapid growth rate (3) metabolic effect due to respiration and photosynthesis. All these explanations are based on the assumption that the coral skeleton represents a structural homogeneous entity. Early microscopic studies of coral skeletons have suggested that coral skeletons are built by two different structures: (1) fibres and (2) centres of calcification confirmed by recent biominerali- sation studies. SIMS O-stable isotopes measurements have been performed on lines of centres of calcification and the surrounding aragonitic fibre on deep-sea coral (Lophe- lia Pertusa). Different transects of O-isotope distribution have been carried out in the septa and in the thick wall of Lophelia pertusa. O-isotopic values of the fibres of the septa and of the wall show a very large range of variation of around 10L' from -5 to +5L' (PDB). O-measurement performed on line of the centre of calcification from the inner part of the septa to the wall show a restricted range of variation which not exceed 1L'. O-values of the centres of calcification in the septa and in the wall are similar with a mean value of -2.9s0.3L'. Temperature derived from O values of the centre of cal- ´ cification are not consistant with the measured ones in situ indicating also a constant fractionation in this microstructure. Coupled with C-isotopes measurements O-isotope distribution should better constraint the growth mechanism, calcification process

Hand-held UXO Discriminator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gasperikova, E.; Smith, J.T.; Kappler, K.N.

2010-04-01

With prior funding (UX-1225, MM-0437, and MM-0838), we have successfully designed and built a cart-mounted Berkeley UXO Discriminator (BUD) and demonstrated its performance at various test sites (e.g., Gasperikova et al., 2007, 2009). It is a multi-transmitter multi-receiver active electromagnetic system that is able to discriminate UXO from scrap at a single measurement position, hence eliminates equirement of a very accurate sensor location. The cart-mounted system comprises of three orthogonal transmitters and eight pairs of differenced receivers (Smith et al., 2007). Receiver coils are located on ymmetry lines through the center of the system and see identical fields during themore » on-time of the pulse in all of the transmitter coils. They can then be wired in opposition to produce zero output during the n-ime of the pulses in three orthogonal transmitters. Moreover, this configuration dramatically reduces noise in the measurements by canceling the background electromagnetic fields (these fields are uniform ver the scale of the receiver array and are consequently nulled by the differencing operation), and by canceling the noise contributed by the tilt of the receivers in the Earth's magnetic field, and therefore reatly enhances receivers sensitivity to the gradients of the target.« less

Suitability of capillary blood obtained by a minimally invasive lancet technique to detect subclinical ketosis in dairy cows by using 3 different electronic hand-held devices.

PubMed

Kanz, P; Drillich, M; Klein-Jöbstl, D; Mair, B; Borchardt, S; Meyer, L; Schwendenwein, I; Iwersen, M

2015-09-01

The objective of this study was to evaluate the suitability of capillary blood obtained by a minimally invasive lancet technique to detect subclinical ketosis in 49 prepartum and 191 postpartum Holstein-Friesian cows using 3 different electronic hand-held devices [FreeStyle Precision (FSP, Abbott), GlucoMen LX Plus (GLX, A. Menarini), NovaVet (NOV, Nova Biomedical)]. The β-hydroxybutyrate (BHBA) concentration in serum harvested from coccygeal blood samples was analyzed in a laboratory and used as a reference value. Capillary samples were obtained from the skin of the exterior vulva by using 1 of 3 different lancets. In all samples, the concentration of BHBA was immediately analyzed with all 3 hand-held devices used in random order. All lancets used in the study were eligible for capillary blood collection but differed in the total number of incisions needed. Spearman correlation coefficients between the BHBA concentrations in capillary blood and the reference test were highly significant with 83% for the FSP, 73% for the NOV, and 63% for the GLX. Using capillary blood, the FSP overestimated the mean BHBA concentration compared with the reference test (+0.08 mmol/L), whereas the GLX and NOV underestimated the mean concentration (-0.07 and -0.01 mmol/L). When a BHBA concentration of 1.2 mmol/L in serum was used to define subclinical ketosis, the corresponding analyses of receiver operating characteristics resulted in optimized thresholds for capillary blood of 1.1 mmol/L for the NOV and GLX devices, and of 1.0 mmol/L for the FSP. Based on these thresholds, sensitivities (Se) and specificities (Sp) were 89 and 84% for the NOV, 80 and 89% for the GLX, and 100 and 76% for the FSP. Based on a serum BHBA concentration of 1.4 mmol/L, analyses of receiver operating characteristics resulted in optimized cut-offs of 1.4 mmol/L for the FSP (Se 100%, Sp 92%), 1.3 mmol/L for the NOV (Se 80%, Sp 95%), and 1.1 mmol/L (Se 90%, Sp 85%) for the GLX. Using these optimized thresholds

Isotopic Resonance Hypothesis: Experimental Verification by Escherichia coli Growth Measurements

NASA Astrophysics Data System (ADS)

Xie, Xueshu; Zubarev, Roman A.

2015-03-01

Isotopic composition of reactants affects the rates of chemical and biochemical reactions. As a rule, enrichment of heavy stable isotopes leads to progressively slower reactions. But the recent isotopic resonance hypothesis suggests that the dependence of the reaction rate upon the enrichment degree is not monotonous. Instead, at some ``resonance'' isotopic compositions, the kinetics increases, while at ``off-resonance'' compositions the same reactions progress slower. To test the predictions of this hypothesis for the elements C, H, N and O, we designed a precise (standard error +/-0.05%) experiment that measures the parameters of bacterial growth in minimal media with varying isotopic composition. A number of predicted resonance conditions were tested, with significant enhancements in kinetics discovered at these conditions. The combined statistics extremely strongly supports the validity of the isotopic resonance phenomenon (p << 10-15). This phenomenon has numerous implications for the origin of life studies and astrobiology, and possible applications in agriculture, biotechnology, medicine, chemistry and other areas.

Learning "Hands On."

ERIC Educational Resources Information Center

Ritter, Janice T.

2001-01-01

Discusses a computer teacher's incorporation of hand-held computer technology into her third- and fifth-grade students' study of acid rain. The project successfully brought two grade levels together for cross-grade research, provided an opportunity for classroom teachers and technology specialists to work collaboratively, and enhanced students'…

Detector optimization for hand-held CsI(Tl)/HgI{sub 2} gamma-ray scintillation spectrometer applications

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Y.J.; Patt, B.E.; Iwanczyk, J.S.

Gamma-ray spectrometers using mercuric iodide (HgI{sub 2}) photodetectors (PDs) coupled with CsI(Tl) scintillators have shown excellent energy resolutions and high detection efficiency at room temperature. Additionally HgI{sub 2} semiconductor PDs allow for extreme miniaturization of the detector packaging compared with photomultiplier tube (PMT) based detectors. These advantages make possible the construction of a new generation of hand-held gamma-ray spectrometers. Studies of detector optimization for this application have been undertaken. Several contact materials including hydrogen and semi-transparent metal films have been evaluated and compared for their performances and long term stability. In order to provide higher gamma-ray detection efficiency (i.e., largermore » scintillator volume), but without causing significant degradation of the excellent response achieved with the matched scintillator/PD interface, the scintillator/PD configuration has been studied. A Monte Carlo simulation model has been developed so that the spectral shape can be predicted for various scintillator shapes and surface treatments.« less

The influence of room temperature on Mg isotope measurements by MC-ICP-MS.

PubMed

Zhang, Xing-Chao; Zhang, An-Yu; Zhang, Zhao-Feng; Huang, Fang; Yu, Hui-Min

2018-03-24

We observed that the accuracy and precision of magnesium (Mg) isotope analyses could be affected if the room temperature oscillated during measurements. To achieve high quality Mg isotopic data, it is critical to evaluate how the unstable room temperature affects Mg isotope measurements by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). We measured the Mg isotopes for the reference material DSM-3 using MC-ICP-MS under oscillating room temperatures in spring. For a comparison, we also measured the Mg isotopes under stable room temperatures, which was achieved by the installation of an improved temperature control system in the laboratory. The δ 26 Mg values measured under oscillating room temperatures have a larger deviation (δ 26 Mg from -0.09 to 0.08‰, with average δ 26 Mg = 0.00 ± 0.08 ‰) than those measured under a stable room temperature (δ 26 Mg from -0.03 to 0.03‰, with average δ 26 Mg = 0.00 ± 0.02 ‰) using the same MC-ICP-MS system. The room temperature variation can influence the stability of MC-ICP-MS. Therefore, it is critical to keep the room temperature stable to acquire high precise and accurate isotopic data when using MC-ICP-MS, especially when using the sample-standard bracketing (SSB) correction method. This article is protected by copyright. All rights reserved.

Natural Isotope Abundance in Metabolites: Techniques and Kinetic Isotope Effect Measurement in Plant, Animal, and Human Tissues.

PubMed

Tea, Illa; Tcherkez, Guillaume

2017-01-01

The natural isotope abundance in bulk organic matter or tissues is not a sufficient base to investigate physiological properties, biosynthetic mechanisms, and nutrition sources of biological systems. In fact, isotope effects in metabolism lead to a heterogeneous distribution of 2 H, 18 O, 13 C, and 15 N isotopes in metabolites. Therefore, compound-specific isotopic analysis (CSIA) is crucial to biological and medical applications of stable isotopes. Here, we review methods to implement CSIA for 15 N and 13 C from plant, animal, and human samples and discuss technical solutions that have been used for the conversion to CO 2 and N 2 for IRMS analysis, derivatization and isotope effect measurements. It appears that despite the flexibility of instruments used for CSIA, there is no universal method simply because the chemical nature of metabolites of interest varies considerably. Also, CSIA methods are often limited by isotope effects in sample preparation or the addition of atoms from the derivatizing reagents, and this implies that corrections must be made to calculate a proper δ-value. Therefore, CSIA has an enormous potential for biomedical applications, but its utilization requires precautions for its successful application. © 2017 Elsevier Inc. All rights reserved.

Negligible fractionation of Kr and Xe isotopes by molecular diffusion in water

NASA Astrophysics Data System (ADS)

Tyroller, Lina; Brennwald, Matthias S.; Busemann, Henner; Maden, Colin; Baur, Heinrich; Kipfer, Rolf

2018-06-01

Molecular diffusion is a key transport process for noble gases in water. Such diffusive transport is often thought to cause a mass-dependent fractionation of noble gas isotopes that is inversely proportional to the square root of the ratio of their atomic mass, referred to as the square root relation. Previous studies, challenged the commonly held assumption that the square root relation adequately describes the behaviour of noble gas isotopes diffusing through water. However, the effect of diffusion on noble gas isotopes has only been determined experimentally for He, Ne and Ar to date, whereas the extent of fractionation of Kr and Xe has not been measured. In the present study the fractionation of Kr and Xe isotopes diffusing through water immobilised by adding agar was quantified through measuring the respective isotope ratio after diffusing through the immobilised water. No fractionation of Kr and Xe isotopes was observed, even using high-precision noble gas analytics. These results complement our current understanding on isotopic fractionation of noble gases diffusing through water. Therefore this complete data set builds a robust basis to describe molecular diffusion of noble gases in water in a physical sound manner which is fundamental to assess the physical aspects of gas dynamics in aquatic systems.

Hand-arm vibration disorder among grass-cutter workers in Malaysia.

PubMed

Azmir, Nor Azali; Ghazali, Mohd Imran; Yahya, Musli Nizam; Ali, Mohamad Hanafi

2016-09-01

Prolonged exposure to hand-transmitted vibration from grass-cutting machines has been associated with increasing occurrences of symptoms and signs of occupational diseases related to hand-arm vibration syndrome (HAVS). A cross-sectional study was carried out using an adopted HAVS questionnaire on hand-arm vibration exposure and symptoms distributed to 168 male workers from the grass and turf maintenance industry who use hand-held grass-cutting machines as part of their work. The prevalence ratio and symptom correlation to HAVS between high and low-moderate exposure risk groups were evaluated. There were positive HAVS symptoms relationships between the low-moderate exposure group and the high exposure group among hand-held grass-cutting workers. The prevalence ratio was considered high because there were indicators that fingers turned white and felt numb, 3.63, 95% CI [1.41, 9.39] and 4.24, 95% CI [2.18, 8.27], respectively. Less than 14.3% of workers stated that they were aware of the occupational hand-arm vibration, and it seemed to be related to the finger blanching and numbness. The results suggest that HAVS is under-diagnosed in Malaysia, especially in the agricultural sectors. More information related to safety and health awareness programmes for HAVS exposure is required among hand-held grass-cutting workers.

An embedded system developed for hand held assay used in water monitoring

NASA Astrophysics Data System (ADS)

Wu, Lin; Wang, Jianwei; Ramakrishna, Bharath; Hsueh, Mingkai; Liu, Jonathan; Wu, Qufei; Wu, Chao-Cheng; Cao, Mang; Chang, Chein-I.; Jensen, Janet L.; Jensen, James O.; Knapp, Harlan; Daniel, Robert; Yin, Ray

2005-11-01

The US Army Joint Service Agent Water Monitor (JSAWM) program is currently interested in an approach that can implement a hardware- designed device in ticket-based hand-held assay (currently being developed) used for chemical/biological agent detection. This paper presents a preliminary investigation of the proof of concept. Three components are envisioned to accomplish the task. One is the ticket development which has been undertaken by the ANP, Inc. Another component is the software development which has been carried out by the Remote Sensing Signal and Image Processing Laboratory (RSSIPL) at the University of Maryland, Baltimore County (UMBC). A third component is an embedded system development which can be used to drive the UMBC-developed software to analyze the ANP-developed HHA tickets on a small pocket-size device like a PDA. The main focus of this paper is to investigate the third component that is viable and is yet to be explored. In order to facilitate to prove the concept, a flatbed scanner is used to replace a ticket reader to serve as an input device. The Stargate processor board is used as the embedded System with Embedded Linux installed. It is connected to an input device such as scanner as well as output devices such as LCD display or laptop etc. It executes the C-Coded processing program developed for this embedded system and outputs its findings on a display device. The embedded system to be developed and investigated in this paper is the core of a future hardware device. Several issues arising in such an embedded system will be addressed. Finally, the proof-of-concept pilot embedded system will be demonstrated.

Dual Si and O Isotope Measurement of Lunar Samples Using IRMS

NASA Astrophysics Data System (ADS)

Banerjee, N.; Hill, P. J. A.; Osinski, G. R.

2016-12-01

The use of isotopic systems and their associated theoretical models have become an increasingly sophisticated tool for investigating the origin of planetary bodies in the solar system. It was originally hypothesized that evidence for the impact origin of Moon would manifest itself as an isotopic heterogeneity between lunar and terrestrial samples; however, most isotope systems show no difference between the bulk Earth and Moon. The stable isotopes of both silicon (Si) and oxygen (O) have been essential in further understanding planetary processes including core formation. Historically the analysis of the Si and O isotope ratios in terrestrial and extraterrestrial material has primarily been measured independent of each other through three main techniques: isotope ratio mass spectrometry (IRMS), secondary ion mass spectrometry (SIMS), and multi-collector inductively coupled plasma mass-spectrometry (MC-ICPMS). Each technique has its own strength and weakness in regards to resolution and precision; however, one of the main limiting factors in all three of these techniques rests on the requirement of multiple aliquots. As most literature focuses on the measurement of oxygen or silicon isotopes, this unique line allows for the precise analysis of Si and O isotopes from the same aliquot of bulk sample, which cannot be done with SIMS or ICP-MS analysis. To deal with this problem a unique laser line system has been developed in the Laboratory for Stable Isotope Science at Western University, Canada, that simultaneously extracts SiF4 and O2 from the same 1-2 mg aliquot. We present the application of analyzing both isotopic systems from the sample aliquot to Apollo, meteoritic, and terrestrial samples and its implication for the formation of the Moon. Preliminary results from this line suggest that although the O isotopes ratios are consistent with a homogenous Moon-Earth system, a difference is observed in Si isotopes between Apollo and terrestrial samples compared to

Segmentation of Environmental Time Lapse Image Sequences for the Determination of Shore Lines Captured by Hand-Held Smartphone Cameras

NASA Astrophysics Data System (ADS)

Kröhnert, M.; Meichsner, R.

2017-09-01

The relevance of globally environmental issues gains importance since the last years with still rising trends. Especially disastrous floods may cause in serious damage within very short times. Although conventional gauging stations provide reliable information about prevailing water levels, they are highly cost-intensive and thus just sparsely installed. Smartphones with inbuilt cameras, powerful processing units and low-cost positioning systems seem to be very suitable wide-spread measurement devices that could be used for geo-crowdsourcing purposes. Thus, we aim for the development of a versatile mobile water level measurement system to establish a densified hydrological network of water levels with high spatial and temporal resolution. This paper addresses a key issue of the entire system: the detection of running water shore lines in smartphone images. Flowing water never appears equally in close-range images even if the extrinsics remain unchanged. Its non-rigid behavior impedes the use of good practices for image segmentation as a prerequisite for water line detection. Consequently, we use a hand-held time lapse image sequence instead of a single image that provides the time component to determine a spatio-temporal texture image. Using a region growing concept, the texture is analyzed for immutable shore and dynamic water areas. Finally, the prevalent shore line is examined by the resultant shapes. For method validation, various study areas are observed from several distances covering urban and rural flowing waters with different characteristics. Future work provides a transformation of the water line into object space by image-to-geometry intersection.

Spectroscopic metrology for isotope composition measurements and transfer standards

NASA Astrophysics Data System (ADS)

Anyangwe Nwaboh, Javis; Balslev-Harder, David; Kääriäinen, Teemu; Richmond, Craig; Manninen, Albert; Mohn, Joachim; Kiseleva, Maria; Petersen, Jan C.; Werhahn, Olav; Ebert, Volker

2017-04-01

The World Meteorological Organization (WMO) has identified greenhouse gases such as CO2, CH4 and N2O as critical for global climate monitoring. Other molecules such as CO that has an indirect effect of enhancing global warming are also monitored. WMO has stated compatibility goals for atmospheric concentration and isotope ratio measurements of these gases, e.g. 0.1 ppm for CO2 concentration measurements in the northern hemisphere and 0.01 ‰ for δ13C-CO2. For measurements of the concentration of greenhouse gases, gas analysers are typically calibrated with static gas standards e.g. traceable to the WMO scale or to the International System of Units (SI) through a national metrology institute. However, concentrations of target components, e.g. CO, in static gas standards have been observed to drift, and typically the gas matrix as well as the isotopic composition of the target component does not always reflect field gas composition, leading to deviations of the analyser response, even after calibration. The deviations are dependent on the measurement technique. To address this issue, part of the HIGHGAS (Metrology for high-impact greenhouse gases) project [1] focused on the development of optical transfer standards (OTSs) for greenhouse gases, e.g. CO2 and CO, potentially complementing gas standards. Isotope ratio mass spectrometry (IRMS) [2] is currently used to provide state-of-the-art high precision (in the 0.01 ‰ range) measurements for the isotopic composition of greenhouse gases. However, there is a need for field-deployable techniques such as optical isotope ratio spectroscopy (OIRS) that can be combined with metrological measurement methods. Within the HIGHGAS project, OIRS methods and procedures based on e.g. cavity enhanced spectroscopy (CES) and tunable diode laser absorption spectroscopy (TDLAS), matched to metrological principles have been established for the measurement of 13C/12C and 18O/16O ratios in CO2, 15N/14N ratios in N2O, and 13C/12C and 2H

VAPOR PRESSURE ISOTOPE EFFECTS IN THE MEASUREMENT OF ENVIRONMENTAL TRITIUM SAMPLES.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuhne, W.

2012-12-03

Standard procedures for the measurement of tritium in water samples often require distillation of an appropriate sample aliquot. This distillation process may result in a fractionation of tritiated water and regular light water due to the vapor pressure isotope effect, introducing either a bias or an additional contribution to the total tritium measurement uncertainty. The magnitude of the vapor pressure isotope effect is characterized as functions of the amount of water distilled from the sample aliquot and the heat settings for the distillation process. The tritium concentration in the distillate is higher than the tritium concentration in the sample earlymore » in the distillation process, it then sharply decreases due to the vapor pressure isotope effect and becomes lower than the tritium concentration in the sample, until the high tritium concentration retained in the boiling flask is evaporated at the end of the process. At that time, the tritium concentration in the distillate again overestimates the sample tritium concentration. The vapor pressure isotope effect is more pronounced the slower the evaporation and distillation process is conducted; a lower heat setting during the evaporation of the sample results in a larger bias in the tritium measurement. The experimental setup used and the fact that the current study allowed for an investigation of the relative change in vapor pressure isotope effect in the course of the distillation process distinguish it from and extend previously published measurements. The separation factor as a quantitative measure of the vapor pressure isotope effect is found to assume values of 1.034 {+-} 0.033, 1.052 {+-} 0.025, and 1.066 {+-} 0.037, depending on the vigor of the boiling process during distillation of the sample. A lower heat setting in the experimental setup, and therefore a less vigorous boiling process, results in a larger value for the separation factor. For a tritium measurement in water samples, this implies

Comparison of two exhaled nitric oxide analyzers: the NIOX MINO hand-held electrochemical analyzer and the NOA280i stationary chemiluminescence analyzer.

PubMed

Kim, Sang-Heon; Moon, Ji-Yong; Kwak, Hyun Jung; Kim, Sa Il; Park, Dong Won; Kim, Jee Woo; Kim, Tae Hyung; Sohn, Jang Won; Shin, Dong Ho; Park, Sung Soo; Yoon, Ho Joo

2012-07-01

Measurement of the fraction of nitric oxide (FeNO) in exhaled air is useful in the management of asthma. A new hand-held nitric oxide (NO) analyzer, the NIOX MINO, is simple and easy to use in clinical practice. In this study, FeNO values measured using the NIOX MINO were compared with those obtained using a stationary chemiluminescence analyzer, the Sievers NOA280i. FeNO was measured in 100 adults, using both the NIOX MINO and the NOA280i. Nine (9.0%) of these subjects had asthma. The first acceptable measurement with the NIOX MINO and the mean of two acceptable measurements with the NOA280i were compared. There was a significant correlation between FeNO concentrations measured with the two devices (r = 0.876, P < 0.001). A Bland-Altman plot showed a high degree of agreement between the two devices: the mean inter-device difference was 3.3 parts per billion (ppb), and the 95% limits of agreement were -7.0 and 13.6 ppb. In addition, the mean relative difference was 14.5%, with the 95% limits of agreement being -33.7 and 62.7%. The mean value (± standard error of the mean) for FeNO as measured with the NIOX MINO (18.8 ± 0.9 ppb) was significantly lower than that measured with the NOA280i (22.1 ± 1.2 ppb, P < 0.001). There was a significant correlation, but only moderate agreement, between FeNO values measured with the NIOX MINO and those measured with the NOA280i, with the NIOX MINO values being significantly lower than the NOA280i values. Significant differences in FeNO values obtained with these two NO analyzers should be considered when interpreting the results of FeNO measurements. © 2012 The Authors. Respirology © 2012 Asian Pacific Society of Respirology.

Lifetime measurement of neutron-rich even-even molybdenum isotopes

NASA Astrophysics Data System (ADS)

Ralet, D.; Pietri, S.; Rodríguez, T.; Alaqeel, M.; Alexander, T.; Alkhomashi, N.; Ameil, F.; Arici, T.; Ataç, A.; Avigo, R.; Bäck, T.; Bazzacco, D.; Birkenbach, B.; Boutachkov, P.; Bruyneel, B.; Bruce, A. M.; Camera, F.; Cederwall, B.; Ceruti, S.; Clément, E.; Cortés, M. L.; Curien, D.; De Angelis, G.; Désesquelles, P.; Dewald, M.; Didierjean, F.; Domingo-Pardo, C.; Doncel, M.; Duchêne, G.; Eberth, J.; Gadea, A.; Gerl, J.; Ghazi Moradi, F.; Geissel, H.; Goigoux, T.; Goel, N.; Golubev, P.; González, V.; Górska, M.; Gottardo, A.; Gregor, E.; Guastalla, G.; Givechev, A.; Habermann, T.; Hackstein, M.; Harkness-Brennan, L.; Henning, G.; Hess, H.; Hüyük, T.; Jolie, J.; Judson, D. S.; Jungclaus, A.; Knoebel, R.; Kojouharov, I.; Korichi, A.; Korten, W.; Kurz, N.; Labiche, M.; Lalović, N.; Louchart-Henning, C.; Mengoni, D.; Merchán, E.; Million, B.; Morales, A. I.; Napoli, D.; Naqvi, F.; Nyberg, J.; Pietralla, N.; Podolyák, Zs.; Pullia, A.; Prochazka, A.; Quintana, B.; Rainovski, G.; Reese, M.; Recchia, F.; Reiter, P.; Rudolph, D.; Salsac, M. D.; Sanchis, E.; Sarmiento, L. G.; Schaffner, H.; Scheidenberger, C.; Sengele, L.; Singh, B. S. Nara; Singh, P. P.; Stahl, C.; Stezowski, O.; Thoele, P.; Valiente Dobon, J. J.; Weick, H.; Wendt, A.; Wieland, O.; Winfield, J. S.; Wollersheim, H. J.; Zielinska, M.; PreSPEC Collaboration

2017-03-01

Background: In the neutron-rich A ≈100 mass region, rapid shape changes as a function of nucleon number as well as coexistence of prolate, oblate, and triaxial shapes are predicted by various theoretical models. Lifetime measurements of excited levels in the molybdenum isotopes allow the determination of transitional quadrupole moments, which in turn provides structural information regarding the predicted shape change. Purpose: The present paper reports on the experimental setup, the method that allowed one to measure the lifetimes of excited states in even-even molybdenum isotopes from mass A =100 up to mass A =108 , and the results that were obtained. Method: The isotopes of interest were populated by secondary knock-out reaction of neutron-rich nuclei separated and identified by the GSI fragment separator at relativistic beam energies and detected by the sensitive PreSPEC-AGATA experimental setup. The latter included the Lund-York-Cologne calorimeter for identification, tracking, and velocity measurement of ejectiles, and AGATA, an array of position sensitive segmented HPGe detectors, used to determine the interaction positions of the γ ray enabling a precise Doppler correction. The lifetimes were determined with a relativistic version of the Doppler-shift-attenuation method using the systematic shift of the energy after Doppler correction of a γ -ray transition with a known energy. This relativistic Doppler-shift-attenuation method allowed the determination of mean lifetimes from 2 to 250 ps. Results: Even-even molybdenum isotopes from mass A =100 to A =108 were studied. The decays of the low-lying states in the ground-state band were observed. In particular, two mean lifetimes were measured for the first time: τ =29 .7-9.1+11.3 ps for the 4+ state of 108Mo and τ =3 .2-0.7+0.7 ps for the 6+ state of 102Mo. Conclusions: The reduced transition strengths B (E 2 ) , calculated from lifetimes measured in this experiment, compared to beyond

Stable isotope measurements of evapotranspiration partitioning in a maize field

NASA Astrophysics Data System (ADS)

Hogan, Patrick; Parajka, Juraj; Oismüller, Markus; Strauss, Peter; Heng, Lee; Blöschl, Günter

2017-04-01

Evapotranspiration (ET) is one of the most important processes in describing land surface - atmosphere interactions as it connects the energy and water balances. Furthermore knowledge of the individual components of evapotranspiration is important for ecohydrological modelling and agriculture, particularly for irrigation efficiency and crop productivity. In this study, we tested the application of the stable isotope method for evapotranspiration partitioning to a maize crop during the vegetative stage, using sap flow sensors as a comparison technique. Field scale ET was measured using an eddy covariance device and then partitioned using high frequency in-situ measurements of the isotopic signal of the canopy water vapor. The fraction of transpiration (Ft) calculated with the stable isotope method showed good agreement with the sap flow method. High correlation coefficient values were found between the two techniques, indicating the stable isotope method can successfully be applied in maize. The results show the changes in transpiration as a fraction of evapotranspiration after rain events and during the subsequent drying conditions as well as the relationship between transpiration and solar radiation and vapor pressure deficit.

Hydrogen Isotope Measurements of Organic Acids and Alcohols by Pyrolysis-GC-MS-TC-IRMS

NASA Technical Reports Server (NTRS)

Socki, Richard A.; Fu, Qi; Niles, Paul B.

2011-01-01

One possible process responsible for methane generation on Mars is abiotic formation by Fischer-Tropsch-type (FTT) synthesis during serpentinization reactions. Measurement of carbon and hydrogen isotopes of intermediary organic compounds can help constrain the origin of this methane by tracing the geochemical pathway during formation. Of particular interest within the context of this work is the isotopic composition of organic intermediaries produced on the surfaces of mineral catalysts (i.e. magnetite) during hydrothermal experiments, and the ability to make meaningful and reproducible hydrogen isotope measurements. Reported here are results of experiments to characterize the hydrogen isotope composition of low molecular weight organic acids and alcohols. The presence of these organic compounds has been suggested by others as intermeadiary products made during mineral surface catalyzed reactions. This work compliments our previous study characterizing the carbon isotope composition of similar low molecular weight intermediary organic compounds (Socki, et al, American Geophysical Union Fall meeting, Abstr. #V51B-2189, Dec., 2010). Our hydrogen isotope measurements utilize a unique analytical technique combining Pyrolysis-Gas Chromatograph-Mass Spectrometry-High Temperature Conversion-Isotope Ratio Mass Spectrometry (Py-GC-MS-TC-IRMS). Our technique is unique in that it carries a split of the pyrolyzed GC-separated product to a Thermo DSQ-II? quadrupole mass spectrometer as a means of making qualitative and semi-quantitative compositional measurements of separated organic compounds, therefore both chemical and isotopic measurements can be carried out simultaneously on the same sample.

Separation of copper, iron, and zinc from complex aqueous solutions for isotopic measurement

USGS Publications Warehouse

Borrok, D.M.; Wanty, R.B.; Ridley, W.I.; Wolf, R.; Lamothe, P.J.; Adams, M.

2007-01-01

The measurement of Cu, Fe, and Zn isotopes in natural samples may provide valuable information about biogeochemical processes in the environment. However, the widespread application of stable Cu, Fe, and Zn isotope chemistry to natural water systems remains limited by our ability to efficiently separate these trace elements from the greater concentrations of matrix elements. In this study, we present a new method for the isolation of Cu, Fe, and Zn from complex aqueous solutions using a single anion-exchange column with hydrochloric acid media. Using this method we are able to quantitatively separate Cu, Fe, and Zn from each other and from matrix elements in a single column elution. Elution of the elements of interest, as well as all other elements, through the anion-exchange column is a function of the speciation of each element in the various concentrations of HCl. We highlight the column chemistry by comparing our observations with published studies that have investigated the speciation of Cu, Fe, and Zn in chloride solutions. The functionality of the column procedure was tested by measuring Cu, Fe, and Zn isotopes in a variety of stream water samples impacted by acid mine drainage. The accuracy and precision of Zn isotopic measurements was tested by doping Zn-free stream water with the Zn isotopic standard. The reproducibility of the entire column separation process and the overall precision of the isotopic measurements were also evaluated. The isotopic results demonstrate that the Cu, Fe, and Zn column separates from the tested stream waters are of sufficient purity to be analyzed directly using a multicollector inductively coupled plasma mass spectrometer (MC-ICP-MS), and that the measurements are fully-reproducible, accurate, and precise. Although limited in scope, these isotopic measurements reveal significant variations in ??65Cu (- 1.41 to + 0.30???), ??56Fe (- 0.56 to + 0.34???), and ??66Zn (0.31 to 0.49???) among samples collected from different

Iron Isotopes in Meteorites

NASA Astrophysics Data System (ADS)

Kehm, K.; Alexander, C. M.; Hauri, E. H.

2001-12-01

The recent identification of naturally occurring isotopic mass fractionation of the transition met-als on the Earth has prompted a search for similar variability in meteorites. Studies of Cu, Zn, and Fe, for example, have revealed per-mil level and larger mass fractionations between different bulk meteorites. Such variations can result from temperature-sensitive isotope exchange reactions and kinetic processes, and therefore may reflect conditions in the solar nebula and on meteorite parent bodies. Recent advances in ICP-MS have permitted isotope studies of transition metals and other elements with similarly small isotopic mass dispersions. Among the transition metals, Fe is perhaps the most difficult to analyze by ICP-MS because plasma sources are copious producers of argide molecules that interfere with the measurement of iron isotopes. However, the stable isotope behavior of Fe is of special interest because it is a non-refractory major element in meteorites, present in a variety of mineral associations and redox states. Considerable effort has gone into overcoming the inherent analytical difficulties of measuring Fe using ICP-MS. We recently reported on a technique that achieves argide reduction by operating the plasma source in so-called 'cold' mode. In this presentation, we report results from this ongoing work. To date, analyses of nine different meteorites, and eight individual Tieschitz (H3) chondrules have been completed, along with a number of measurements of the Hawaiian basalt sample Kil1919. All of the bulk meteorite compositions, which include both chondrites and irons, have identical 56Fe/54Fe to within ~ 0.14 per mil (2 sigma), and are indistinguishable from the composition of the terrestrial basalt. The Tieschitz chondrules, on the other hand, tend to have isotopically light compositions. This could reflect formation from fractionated starting material. Alternatively, Fe condensation, under non-equilibrium conditions can enrich light isotopes

[Influence of two positions for measuring instrument adapter on measurement of hand-transmitted vibration in grinding machine].

PubMed

Xie, X S; Zhang, M; Zheng, Y D; Du, X Y; Qi, C

2016-06-20

To investigate the influence of two positions for measuring instrument adapter on the measurement of hand-transmitted vibration in grinding machine using the intraclass correlation coefficient (ICC) of reliability assessment index, and to provide a basis for studies on the measurement standard for hand-transmitted vibration. With reference to the measurement standard for hand-transmitted vibration ISO 5349 Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-Part 1: General requirements and Mechanical vibration-Measurement and evaluation of human exposure to hand-transmitted vibration-Part 2: Practical guidance for measurement at the workplace, the domestic AWA5936 hand-transmitted vibration measuring instrument and SVAN-106 hand-transmitted vibration measuring instrument from Poland were used to measure hand-transmitted vibration in 3 workers for grinding machine in a foundry for 5 days continuously from September to October, 2014, and Y-axis data were recorded and compared. In worker A, the "T" -shaped adapter had a significantly higher mean Y-axis accelerated speed effective value than the "O" -shaped adapter [4.34 m/s(2) (95%CI 4.05(-)4.63) vs 2.32 m/s(2) (95%CI 2.27~2.38) , t=13.781, P<0.01]. In workers B and C, AWA5936 "U" -shaped adapter (placed at the position of the handle of grinding machine) had lower degrees of data variation of 12.55% and 15.77%, respectively, suggesting good data stability. The measurement results showed significant differences across different positions of adapter (P<0.01) and between all adapters except "O" -shaped and line-shaped adapters (all P<0.01) , while the measurement results showed no significant differences between the "O" -shaped and line-shaped adapters (P>0.01). The comparison of the measurement results of AWA5936 vibration measuring instrument with an "U" -shaped adapter and SVAN-106 vibration measuring instrument with an "S" -shaped adapter showed an ICC of >0.80 (ICC=0

Quantitatively measured tremor in hand-arm vibration-exposed workers.

PubMed

Edlund, Maria; Burström, Lage; Hagberg, Mats; Lundström, Ronnie; Nilsson, Tohr; Sandén, Helena; Wastensson, Gunilla

2015-04-01

The aim of the present study was to investigate the possible increase in hand tremor in relation to hand-arm vibration (HAV) exposure in a cohort of exposed and unexposed workers. Participants were 178 male workers with or without exposure to HAV. The study is cross-sectional regarding the outcome of tremor and has a longitudinal design with respect to exposure. The dose of HAV exposure was collected via questionnaires and measurements at several follow-ups. The CATSYS Tremor Pen(®) was used for measuring postural tremor. Multiple linear regression methods were used to analyze associations between different tremor variables and HAV exposure, along with predictor variables with biological relevance. There were no statistically significant associations between the different tremor variables and cumulative HAV or current exposure. Age was a statistically significant predictor of variation in tremor outcomes for three of the four tremor variables, whereas nicotine use was a statistically significant predictor of either left or right hand or both hands for all four tremor variables. In the present study, there was no evidence of an exposure-response association between HAV exposure and measured postural tremor. Increase in age and nicotine use appeared to be the strongest predictors of tremor.

Ionization cross section, pressure shift and isotope shift measurements of osmium

NASA Astrophysics Data System (ADS)

Hirayama, Yoshikazu; Mukai, Momo; Watanabe, Yutaka; Oyaizu, Michihiro; Ahmed, Murad; Kakiguchi, Yutaka; Kimura, Sota; Miyatake, Hiroari; Schury, Peter; Wada, Michiharu; Jeong, Sun-Chan

2017-11-01

In-gas-cell laser resonance ionization spectroscopy of neutral osmium atoms was performed with the use of a two-color two-step laser resonance ionization technique. Saturation curves for the ionization scheme were measured, and the ionization cross section was experimentally determined by solving the rate equations for the ground, intermediate and ionization continuum populations. The pressure shift and pressure broadening in the resonance spectra of the excitation transition were measured. The electronic factor {F}247 for the transition {λ }1=247.7583 nm to the intermediate state was deduced from the measured isotope shifts of stable {}{188,189,{190,192}}Os isotopes. The efficient ionization scheme, pressure shift, nuclear isotope shift and {F}247 are expected to be useful for applications of laser ion sources to unstable nuclei and for nuclear spectroscopy based on laser ionization techniques.

Evaluation of the combined measurement uncertainty in isotope dilution by MC-ICP-MS.

PubMed

Fortunato, G; Wunderli, S

2003-09-01

The combination of metrological weighing, the measurement of isotope amount ratios by a multicollector inductively coupled plasma mass spectrometer (MC-ICP-MS) and the use of high-purity reference materials are the cornerstones to achieve improved results for the amount content of lead in wine by the reversed isotope dilution technique. Isotope dilution mass spectrometry (IDMS) and reversed IDMS have the potential to be a so-called primary method, with which close comparability and well-stated combined measurement uncertainties can be obtained. This work describes the detailed uncertainty budget determination using the ISO-GUM approach. The traces of lead in wine were separated from the matrix by ion exchange chromatography after HNO(3)/H(2)O(2) microwave digestion. The thallium isotope amount ratio ( n((205)Tl)/ n((203)Tl)) was used to correct for mass discrimination using an exponential model approach. The corrected lead isotope amount ratio n((206)Pb)/ n((208)Pb) for the isotopic standard SRM 981 measured in our laboratory was compared with ratio values considered to be the least uncertain. The result has been compared in a so-called pilot study "lead in wine" organised by the CCQM (Comité Consultatif pour la Quantité de Matière, BIPM, Paris; the highest measurement authority for analytical chemical measurements). The result for the lead amount content k(Pb) and the corresponding expanded uncertainty U given by our laboratory was:k(Pb)=1.329 x 10-10mol g-1 (amount content of lead in wine)U[k(Pb)]=1.0 x 10-12mol g-1 (expanded uncertainty U=kxuc, k=2)The uncertainty of the main influence parameter of the combined measurement uncertainty was determined to be the isotope amount ratio R(206,B) of the blend between the enriched spike and the sample.

ICP-MS for isotope ratio measurement

USDA-ARS?s Scientific Manuscript database

The use of stable isotopes in mineral nutrition research has become a fundamental aspect of conducting this research. A gradual transition has occurred, now virtually complete, from radioactive isotope studies to those using stable isotopes. Although primarily used in human research, mineral stable ...

Laser ablation inductively coupled plasma mass spectrometry for direct isotope ratio measurements on solid samples

NASA Astrophysics Data System (ADS)

Pickhardt, Carola; Dietze, Hans-Joachim; Becker, J. Sabine

2005-04-01

Isotope ratio measurements have been increasingly used in quite different application fields, e.g., for the investigation of isotope variation in nature, in geoscience (geochemistry and geochronology), in cosmochemistry and planetary science, in environmental science, e.g., in environmental monitoring, or by the application of the isotope dilution technique for quantification purposes using stable or radioactive high-enriched isotope tracers. Due to its high sensitivity, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) is today a challenging mass spectrometric technique for the direct determination of precise and accurate isotope ratios in solid samples. In comparison to laser ablation quadrupole ICP-MS (LA-ICP-QMS), laser ablation coupled to a double-focusing sector field ICP-MS (LA-ICP-SFMS) with single ion detection offers a significant improvement of sensitivity at low mass resolution, whereby isotope ratios can be measured with a precision to 0.1% relative standard deviation (R.S.D.). In LA-ICP-SFMS, many disturbing isobaric interferences of analyte and molecular ions can be separated at the required mass resolution (e.g., 40Ar16O+ and 56Fe+ for iron isotope ratio measurements). The precision on isotope ratio measurements was improved by one order of magnitude via the simultaneous detection of mass-separated ion currents of isotopes using multiple ion collectors in LA-ICP-MS (LA-MC-ICP-MS). The paper discusses the state of the art, the challenges and limits in isotope ratio measurements by LA-ICP-MS using different instrumentations at the trace and ultratrace level in different fields of application as in environmental and biological research, geochemistry and geochronology with respect to their precision and accuracy.

Hydrogeochemistry and isotope hydrology of surface water and groundwater systems in the Ellembelle district, Ghana, West Africa

NASA Astrophysics Data System (ADS)

Edjah, A. K. M.; Akiti, T. T.; Osae, S.; Adotey, D.; Glover, E. T.

2017-05-01

An integrated approach based on the hydrogeochemistry and the isotope hydrology of surface water and groundwater was carried out in the Ellembelle district of the Western Region of Ghana. Measurement of physical parameters (pH, temperature, salinity, total dissolved solutes, total hardness and conductivity), major ions (Ca2+, Mg2+, Na+, K+, HCO3 -, Cl-, SO4 2- and NO3 -), and stable isotopes (δ2H and δ18O) in 7 rivers, 13 hand-dug wells and 18 boreholes were taken. Na+ was the dominant cation and HCO3 - was the dominant anion for both rivers and groundwater. The dominant hydrochemical facies for the rivers were Na-K-HCO3 - type while that of the groundwater (hand-dug wells and boreholes) were Na-Cl and Na-HCO3 - type. According to the Gibbs diagram, majority of the rivers fall in the evaporation-crystallization field and majority of the hand-dug wells and the boreholes fall in the rock dominance field. From the stable isotope composition measurements, all the rivers appeared to be evaporated, 60 % of the hand-dug wells and 70 % of the boreholes clustered along and in between the global meteoric water line and the local meteoric water line, suggesting an integrative and rapid recharge from meteoric origin.

Iron isotope fractionation among magnetite, pyrrhotite, chalcopyrite, rhyolite melt and aqueous fluid at magmatic-hydrothermal conditions

NASA Astrophysics Data System (ADS)

Bilenker, L. D.; Simon, A.; Lundstrom, C.; Gajos, N.

2012-12-01

Fractionation of non-traditional stable isotopes (NTSI) such as Fe in magmatic systems is a relatively understudied subject. The fractionation of Fe stable isotopes has been quantified in some natural igneous samples, but there is a paucity of experimental data that could provide further insight into the causative processes of the observed fractionation. Substantial experimental work has been performed at higher temperatures pertaining to the formation of chondrites and the Earth's core, but only a handful of studies have addressed crustal rocks. To fill this knowledge gap, we performed isothermal, isobaric experiments containing mineral (e.g., magnetite, Fe-sulfides) and fluid, or mineral, rhyolite melt, and fluid assemblages to quantify equilibrium fractionation factors (α). These data, to our knowledge, are the first data that quantify the effect of a fluid phase on iron isotope fractionation at conditions appropriate for evolving magmatic systems. Charges were run inside gold capsules held in a René-41 cold seal vessel, and heated to 400, 600, or 800°C at 150 MPa for mineral-fluid, and 800°C and 100 MPa for mineral-melt-fluid runs. Use of the René vessel fixed the fO2 at the NNO buffer, an oxidation state consistent with arc magmas. The isotopic compositions of the starting and quenched phases were obtained by using a Multi-Collector Plasma Mass Spectrometer (MC-ICP-MS). Equilibrium was assessed by performing time-series runs and the three-isotope method, used only once before in a similar Fe isotope study. Correlation between Fe isotope mass and oxidation state is also being explored. Magnetite-fluid results indicate enrichment of heavy Fe isotopes in the mineral relative to the fluid, consistent with measurements of felsic igneous rocks. Magnetite-melt-fluid relationships are also consistent with measurements of natural samples. In the latter assemblage, over the course of the run, the rhyolite melt becomes heavy relative to the fluid while magnetite

On-line Differential Thermal Isotope Analysis: A New Method for Measuring Oxygen and Hydrogen Isotopes of Hydration Water in Minerals

NASA Astrophysics Data System (ADS)

Bauska, T.; Hodell, D. A.; Walters, G.

2016-12-01

Oxygen (16O,17O,18O) and hydrogen (H,D) isotopes of hydration water in minerals provide a rich source of information about the conditions under which hydrated minerals form on Earth and other planetary bodies (e.g. Mars). We have developed a new method for measuring different types of bonded water (e.g., molecular, hydroxyl) contained in hydrated minerals by coupling a thermal gravimeter (TG) and a cavity ringdown laser spectrometer (CRDS). The method involves step heating a mineral sample, precisely measuring the weight loss and enthalpy as the sample undergoes dehydration and dehydroxylation, whilst simultaneously determining the oxygen and hydrogen isotopes of the water vapor evolved from the mineral sample by cavity ring-down laser spectroscopy (CRDS). Nitrogen carrier gas is used to transfer the sample from the TG to the CRDS via a heated line and interface box. The interface includes the capability of (i) cryogenic trapping discrete types of water for samples containing small amounts of water; (ii) injecting small quantities of water of known isotopic value for calibration; and (iii) converting volatile organic compounds to nascent amounts of water using a catalyst. The CRDS continually measures water vapor concentration in the optical cavity and hydrogen and oxygen isotope ratios. Isotopic values are calculated by integrating the product of the water amount and its isotopic value for the separated peaks after correcting for background. Precision of the method was estimated by comparing isotope results of total water for gypsum measured by DTIA with our conventional method of extraction and analysis (Gázquez et al., 2015. Rapid Communications in Mass Spectrometry, 29, 1997-2006). Errors for the isotopic values of total hydration water vary between ±0.08 and ±0.34 ‰ for δ18O and between ±0.16 and ±0.86 ‰ for δD. We demonstrate the application of the DTIA method to a variety of hydrous minerals and mineraloids including gypsum, clays, and amorphous

Hand function in workers with hand-arm vibration syndrome.

PubMed

Cederlund, R; Isacsson, A; Lundborg, G

1999-01-01

Hand-arm vibration syndrome has been specially addressed in the Scandinavian countries in recent years, but the syndrome is still not sufficiently recognized in many countries. The object of this preliminary study was to describe the nature and character of vibration-induced impairment in the hands of exposed workers. Twenty symptomatic male workers (aged 28 to 65 years) subjected to vibration by hand-held tools were interviewed about subjective symptoms and activities of daily living and were assessed with a battery of objective tests for sensibility, dexterity, grip function, and grip strength. The test results were compared with normative data. The majority of patients complained of cold intolerance, numbness, pain, sensory impairment, and difficulties in handling manual tools and in handwriting. The various objective tests showed considerable variation in indications of pathologic outcome, revealing differences in sensitivity to detect impaired hand function. Semmes-Weinstein monofilament testing for perception of light touch-deep pressure sensation, the small-object shape identification test, and moving two-point discrimination testing for functional sensibility provided the most indications of pathologic outcomes. The authors conclude that vibration-exposed patients present considerable impairment in hand function.

Existing and emerging technologies for measuring stable isotope labelled retinol in biological samples: isotope dilution analysis of body retinol stores.

PubMed

Preston, Tom

2014-01-01

This paper discusses some of the recent improvements in instrumentation used for stable isotope tracer measurements in the context of measuring retinol stores, in vivo. Tracer costs, together with concerns that larger tracer doses may perturb the parameter under study, demand that ever more sensitive mass spectrometric techniques are developed. GCMS is the most widely used technique. It has high sensitivity in terms of sample amount and uses high resolution GC, yet its ability to detect low isotope ratios is limited by background noise. LCMSMS may become more accessible for tracer studies. Its ability to measure low level stable isotope tracers may prove superior to GCMS, but it is isotope ratio MS (IRMS) that has been designed specifically for low level stable isotope analysis through accurate analysis of tracer:tracee ratios (the tracee being the unlabelled species). Compound-specific isotope analysis, where GC is interfaced to IRMS, is gaining popularity. Here, individual 13C-labelled compounds are separated by GC, combusted to CO2 and transferred on-line for ratiometric analysis by IRMS at the ppm level. However, commercially-available 13C-labelled retinol tracers are 2 - 4 times more expensive than deuterated tracers. For 2H-labelled compounds, GC-pyrolysis-IRMS has now become more generally available as an operating mode on the same IRMS instrument. Here, individual compounds are separated by GC and pyrolysed to H2 at high temperature for analysis by IRMS. It is predicted that GC-pyrolysis-IRMS will facilitate low level tracer procedures to measure body retinol stores, as has been accomplished in the case of fatty acids and amino acids. Sample size requirements for GC-P-IRMS may exceed those of GCMS, but this paper discusses sample preparation procedures and predicts improvements, particularly in the efficiency of sample introduction.

Prosthetic Hand Lifts Heavy Loads

NASA Technical Reports Server (NTRS)

Carden, James R.; Norton, William; Belcher, Jewell G.; Vest, Thomas W.

1991-01-01

Prosthetic hand designed to enable amputee to lift diverse heavy objects like rocks and logs. Has simple serrated end effector with no moving parts. Prosthesis held on forearm by system of flexible straps. Features include ruggedness, simplicity, and relatively low cost.

Development and Deployment of a Portable Water Isotope Analyzer for Accurate, Continuous and High-Frequency Oxygen and Hydrogen Isotope Measurements in Water Vapor and Liquid Water

NASA Astrophysics Data System (ADS)

Dong, Feng; Baer, Douglas

2010-05-01

Stable isotopes of water in liquid and vapor samples are powerful tracers to investigate the hydrological cycle and ecological processes. Therefore, continuous, in-situ and accurate measurements of del_18O and del_2H are critical to advance the understanding of water cycle dynamics around the globe. Furthermore, the combination of meteorological techniques and high-frequency isotopic water measurements can provide detailed time-resolved information on the eco-physiological performance of plants and enable improved understanding of water fluxes at ecosystem scales. In this work, we present recent laboratory development and field deployment of a novel Water Vapor Isotope Analyzer (WVIA), based on cavity enhanced laser absorption spectroscopy, capable of simultaneous in-situ measurements of del_18O and del_2H and water mixing ratio with high precision and high frequency (up to 10 Hz measurement rate). In addition, to ensure the accuracy of the water vapor isotope measurements, a novel Water Vapor Isotope Standard Source (WVISS), based on the instantaneous evaporation of micro-droplets of liquid water (with known isotope composition), has been developed to provide the reference water vapor with widely adjustable mixing ratio (500-30,000 ppmv) for real-time calibration of the WVIA. The comprehensive system that includes the WVIA and WVISS has been validated in extensive laboratory and field studies to be insensitive to ambient temperature changes (5-40 C) and to changes in water mixing ratio over a wide range of mixing ratios. In addition, by operating in the dual inlet mode, measurement drift has essentially been eliminated. The system (WVIA+WVISS) has also been deployed for long-term unattended continuous measurements in the field. In addition to water vapor isotope measurements, the new Water Vapor Isotopic Standard Source (WVISS) may be combined with the WVIA to provide continuous isotopic measurements of liquid water samples at rapid data rate. The availability of

Advances in Multicollector ICPMS for precise and accurate isotope ratio measurements of Uranium isotopes

NASA Astrophysics Data System (ADS)

Bouman, C.; Lloyd, N. S.; Schwieters, J.

2011-12-01

The accurate and precise determination of uranium isotopes is challenging, because of the large dynamic range posed by the U isotope abundances and the limited available sample material. Various mass spectrometric techniques are used for the measurement of U isotopes, where TIMS is the most accepted and accurate one. Multicollector inductively coupled plasma mass spectrometry (MC-ICPMS) can offer higher productivity compared to TIMS, but is traditionally limited by low efficiency of sample utilisation. This contribution will discuss progress in MC-ICPMS for detecting 234U, 235U, 236U and 238U in various uranium reference materials from IRMM and NBL. The Thermo Scientific NEPTUNE Plus with Jet Interface offers a modified dry plasma ICP interface using a large interface pump combined with a special set of sample and skimmer cones giving ultimate sensitivity for all elements across the mass range. For uranium, an ion yield of > 3 % was reported previously [1]. The NEPTUNE Plus also offers Multi Ion Counting using discrete dynode electron multipliers as well as two high abundance-sensitivity filters to discriminate against peak tailing effects on 234U and 236U originating from the major uranium beams. These improvements in sensitivity and dynamic range allow accurate measurements of 234U, 235U and 236U abundances on very small samples and at low concentration. In our approach, minor U isotopes 234U and 236U were detected on ion counters with high abundance sensitivity filters, whereas 235U and 238U were detected on Faraday Cups using a high gain current amplifier (10e12 Ohm) for 235U. Precisions and accuracies for 234U and 236U were down to ~1%. For 235U, subpermil levels were reached.

Continuous-flow water sampler for real-time isotopic water measurements

NASA Astrophysics Data System (ADS)

Carter, J.; Dennis, K.

2013-12-01

Measuring the stable isotopes of liquid water (δ18O and δD) is a tool familiar to many Earth scientists, but most current techniques require discrete sampling. For example, isotope ratio mass spectrometry requires the collection of aliquots of water that are then converted to CO2, CO or H2 for analysis. Similarly, laser-based techniques, such as Cavity Ring-Down Spectroscopy (CRDS) convert discrete samples (typically < 2μL) of liquid water to water vapor using a flash vaporization process. By requiring the use of discrete samples fine-scale spatial and temporal studies of changes in δ18O and δD are limited. Here we present a continuous-flow water sampler that will enable scientists to probe isotopic changes in real-time, with applications including, but not limited to, quantification of the 'amount effect' (Dansgaard, 1964) during an individual precipitation event or storm track, real-time mixing of water in river systems, and shipboard continuous water measurements (Munksgaard et al., 2012). Due to the inherent ability of CRDS to measure a continuous flow of water vapor it is an ideal candidate for interfacing with a continuous water sampling system. Here we present results from the first commercially available continuous-flow water sampler, developed by engineers at Picarro. This peripheral device is compatible with Picarro CRDS isotopic water analyzers, allowing real-time, continuous isotopic measurements of liquid water. The new device, which expands upon the design of Munskgaard et al. (2011), utilizes expanded polytetrafluoroethylene (ePTFE) membrane technology to continuously generate gas-phase water, while liquid water is pumped through the system. The water vapor subsequently travels to the CRDS analyzer where the isotopic ratios are measured and recorded. The generation of water vapor using membrane technology is sensitive to environmental conditions, which if not actively control, lead to sustainable experimental noise and drift. Consequently, our

Measurement of the Isotopic Signature of Soil Carbon Dioxide: Methods Development and Initial Field Results

NASA Astrophysics Data System (ADS)

Kayler, Z.; Rugh, W.; Mix, A. C.; Bond, B. J.; Sulzman, E. W.

2005-12-01

Soil respiration is a significant component of ecosystem respiration and its isotopic composition is likely to lend insight into ecosystem processes. We have designed probes to determine the isotopic signature of soil-respired CO2 using a two end-member mixing model approach (i.e., Keeling plot). Each probe consists of three 35 ml PVC chambers cased in fiberglass mesh and connected to the soil surface via stainless steel tubing with a septa-lined swagelok fitting. Chambers are vertically connected such that they sample gases at depth intervals centered on 5, 15, and 30 cm. Gases are sampled via a hand vacuum pump equipped with a two-way valve, which allows vials pre-filled with N2 gas in the laboratory to be evacuated and re-filled with only a single septa puncture in the field. Data indicate samples can be stored reliably for up to three days if punctured septa are coated in silicone sealant. To test whether this field sampling method was robust, we constructed a carbon-free sand column out of PVC pipe into which we plumbed a tank of known CO2 concentration and isotopic composition. We have tested the effects of wetting and flow rate on our ability to reproduce tank values. A linear model (geometric mean regression) yielded a more negative isotopic value than the actual gas, but a simple polynomial curve fit the tank value. After laboratory testing, the probes were established in a steep drainage in the H.J. Andrews LTER site in the Cascade Mountains of western Oregon (as part of the Andrews Airshed project). We established a transect of five 10 m2 plots with four soil probes and a companion respiration collar and measured soil CO2 efflux and soil δ13CO2 values biweekly from June-Sept. Results indicate there is a clear difference in isotopic and respiration flux patterns between the north- and south-facing slopes, with the north facing slope exhibiting higher fluxes and more 13C enriched respiration. The temporal pattern of respiration correlates well with

Tracing source pollution in soils using cadmium and lead isotopes.

PubMed

Cloquet, C; Carignan, J; Libourel, G; Sterckeman, T; Perdrix, E

2006-04-15

Tracing the source of heavy metals in the environment is of key importance for our understanding of their pollution and natural cycles in the surface Earth reservoirs. Up to now, most exclusively Pb isotopes were used to effectively trace metal pollution sources in the environment. Here we report systematic variations of Cd isotope ratios measured in polluted topsoils surrounding a Pb-Zn refinery plant in northern France. Fractionated Cd was measured in soil samples surrounding the refinery, and this fractionation can be attributed to the refining processes. Despite the Cd isotopic ratios being precisely measured, the obtained uncertainties are still large compared to the total isotopic variation. Nevertheless, for the first time, Cd isotopically fractionated by industrial processes may be traced in the environment. On the same samples, Pb isotope systematics suggested that materials actually used by the refinery were not the major source of Pb in soils, probably because refined ore origins changed over the 100 years of operation. On the other hand, Cd isotopes and concentrations measured in topsoils allowed identification of three main origins (industrial dust and slag and agriculture), assuming that all Cd ores are not fractionated, as suggested by terrestrial rocks so far analyzed, and calculation of their relative contributions for each sampling point. Understanding that this refinery context was an ideal situation for such a study, our results lead to the possibility of tracing sources of anthropogenic Cd and better constrain mixing processes, fluxes, transport, and phasing out of industrial input in nature.

Evaluation of a hand-held blood gas analyzer for rapid determination of blood gases, electrolytes and metabolites in intensive care setting.

PubMed

Luukkonen, Antti A M; Lehto, Tiina M; Hedberg, Pirjo S M; Vaskivuo, Tommy E

2016-04-01

Intensive care units, operating rooms, emergency departments, and neonatology units need rapid measurements of blood gases, electrolytes, and metabolites. These analyses can be performed in a central laboratory or at the clinic with traditional or compact cassette-type blood gas analyzers such as the epoc blood gas testing system for analyzing whole blood samples at the bedside. In this study, the performance and interchangeability of a hand-held epoc blood gas analyzer was evaluated. The analytical performance of the epoc analyzer was evaluated by determining within-and between-run precisions. The accuracy of the epoc analyzer was assessed by comparing patient results from the device with those obtained with the Siemens Rapidlab 1265 and Rapidpoint RP500 and Siemens Dimension Vista and Sysmex XE-2100 analyzers. The following parameters were measured: pH, pCO2, pO2, Hb (calc), Na+, K+, iCa2+, glucose, and lactate. The CV% of the epoc's between-day imprecision for the various parameters varied from 0.4 to 8.6. The within-run imprecision CV% varied from 0.6 to 5.2. The squared regression coefficient (R2) between the epoc and RL1265 varied from 0.94 to 0.99, with the exception of Na+ and Ca2+ (R2≥0.82). The correlation (R2) of Na+ and K+ between epoc and Dimension Vista was 0.73 and 0.89, respectively. The correlation (R2) of Hb between the epoc and the XE-2100 analyzer was 0.94. With most of the measured blood gas parameters, the epoc analyzer correlated well with reference techniques. The epoc analyzer is suitable for rapid measurement of the blood gases, the electrolytes, and the metabolites in the ICU.

Recent advances in understanding atmospheric CO based on stable isotope measurements

NASA Astrophysics Data System (ADS)

Popa, Maria Elena; Naus, Stijn; Ferrero Lopez, Noelia; Vijverberg, Sem; de Leeuw, Selma; Röckmann, Thomas

2017-04-01

Carbon monoxide (CO) plays an important role for atmospheric chemistry and for carbon cycling in the atmosphere. Via its reaction with the OH radical it influences concentrations of many other trace gases, it is an important precursor for O3 formation, and its oxidation leads to the formation of about 1 Pg C per year of CO2. The natural and anthropogenic sources of CO are subject to relatively large temporal changes due to natural variability (e.g. biomass burning), industrial activity and mitigation measures (e.g. fossil fuel burning), variations in precursor compounds (e.g. CH4 and VOC) and variations in the abundance of the OH radical in the atmosphere, which are difficult to quantify. Isotope measurements can be used to distinguish between the effects of individual sources and sinks to put tighter constrains on its budget, but the isotopic characterization of the CO sources is in many cases still based on a few relatively old measurements that did not allow to account for dependence on parameters. We will present an update of the isotopic composition of several sources and removal processes of CO that have been carried out in the past years with the automated continuous-flow IRMS system at Utrecht University. This includes: - the previously unknown isotopic composition of direct biogenic CO emissions - a surprisingly large variability in the isotopic composition of CO emitted by different vehicles and single vehicles under various driving conditions - previously very poorly investigated signatures, like the fractionation in the removal of CO by soils, and its interaction with CO that is simultaneously emitted from soil. These results from process specific investigations will be linked to recent atmospheric measurements at various locations.

Integrated optical detection of autonomous capillary microfluidic immunoassays:a hand-held point-of-care prototype.

PubMed

Novo, P; Chu, V; Conde, J P

2014-07-15

The miniaturization of biosensors using microfluidics has potential in enabling the development of point-of-care devices, with the added advantages of reduced time and cost of analysis with limits-of-detection comparable to those obtained through traditional laboratory techniques. Interfacing microfluidic devices with the external world can be difficult especially in aspects involving fluid handling and the need for simple sample insertion that avoids special equipment or trained personnel. In this work we present a point-of-care prototype system by integrating capillary microfluidics with a microfabricated photodiode array and electronic instrumentation into a hand-held unit. The capillary microfluidic device is capable of autonomous and sequential fluid flow, including control of the average fluid velocity at any given point of the analysis. To demonstrate the functionality of the prototype, a model chemiluminescence ELISA was performed. The performance of the integrated optical detection in the point-of-care prototype is equal to that obtained with traditional bench-top instrumentation. The photodiode signals were acquired, displayed and processed by a simple graphical user interface using a computer connected to the microcontroller through USB. The prototype performed integrated chemiluminescence ELISA detection in about 15 min with a limit-of-detection of ≈2 nM with an antibody-antigen affinity constant of ≈2×10(7) M(-1). Copyright © 2014 Elsevier B.V. All rights reserved.

[Does the hand solely belong in the hands of a qualified hand surgeon?

PubMed

Güven, Asim; Kols, Kerstin; Fischer, Klaus; Schönberger, Michael; Allert, Sixtus

2017-09-01

Background In Germany, Hand Surgery is an additional qualification that can only be obtained by a three-year training after a completed residency in General Surgery, Plastic Surgery or Trauma and Orthopaedic Surgery. Nevertheless, injuries and diseases of the hand are also treated by physicians without this particular qualification. It is questionable whether these treatments more often lead to medical malpractice. Material and Methods 376 charges of medical malpractice in surgical treatments of the hand and forearm that were closed in 2014 and 2015 were collected by the Arbitration Board for Medical Liability Issues of the Medical Association of North Germany.Cases with proven medical malpractice were classified by the qualification of the physician in charge and analysed. A statistical analysis was performed with the use of the program SPSS (IBM). Results Medical malpractice was proven in 42 of 113 cases with an attending physician who held the additional qualification for Hand Surgery (37.2 %). For physicians without this qualification, the figures were 79 out of 155 (51.0 %) in the group of trauma and orthopaedic surgeons and 54 out of 108 (50.0 %) in the group of general surgeons. The differences between the hand surgeons and the trauma and orthopaedic surgeons (p = 0.017) and between hand surgeons and general surgeons were significant (p = 0.037). Conclusions It was shown that physicians with an additional qualification in hand surgery had signifcantly fewer proven medical malpratice cases than physicians without this qualification. The following trends were observed in the cases of the physicians without the additional qualification in hand surgery: underestimation of the severity of trauma to soft tissues and infections of the hand, errors in the surgical examination of the hand, including functional tests of tendons and nerves, as well as in diagnostic findings after X-ray studies of the hand. Georg Thieme Verlag KG Stuttgart · New York.

Portable Cavity Ringdown Spectrometer for Methane Isotope Ratio Measurements

NASA Astrophysics Data System (ADS)

Bostrom, G.; Rice, A.; Atkinson, D.

2008-12-01

Close to 45% (244 Tg/yr) of the methange (CH4) in the atmosphere is produced in anaerobic soil conditions (wetlands and rice paddies). Under aerobic soil conditions, bacteria oxidize CH4 to produce CO2 and H2O. Both production and oxidation rates depend on soil composition, nutrient loadings, water content, and plant conditions, but these dependencies are not well characterized. Measurements of CH4 isotope ratios can provide a better understanding of CH4 processes in natural and man- made ecosystems. Here we present progress on the development of a field deployable instrument capable of making precision 13CH4/12CH4 and CH3D/ CH4 isotope ratio measurements of CH4. Moving the instrument out of the lab and into the field will significantly improve the spatial and temporal resolution of data and enhance the study of plant-soil-atmosphere CH4 source and sink processes. Our instrument is a Near-IR (1280-1340 nm) tunable diode laser Cavity Ringdown Spectroscopy (CRDS) system. CRDS is a technique in which the laser injects energy into a high finesse cavity by tuning to one of the cavity resonant modes, resulting in a buildup of energy. At some threshold intra-cavity intensity the injection is stopped, and the intensity decays exponentially due to losses such as absorption by molecules. If the laser is tuned to an absorption line of a sample gas, the concentration of the molecule is proportional to the decay constant (according to the Beer-Lambert law)--scanning over a frequency range produces an absorption spectrum. Currently our system has a resolution of 150 MHz scanning over a 30 GHz (0.2 nm) region, allowing us to resolve peaks at pressures of 100 torr. Using combinations of CH4 standard (natural isotopic abundance) and a 99% pure 13CH4 standard, we identified several lines in the CH4 HITRAN Database that we attribute to 13CH4. We use these and 12CH4 lines within the same region to measure 13CH4 concentration, 12CH4 concentration, and the isotope ratio (13C/12C and D

Uranium Isotopic Ratio Measurements of U3O8 Reference Materials by Atom Probe Tomography

DOE Office of Scientific and Technical Information (OSTI.GOV)

Fahey, Albert J.; Perea, Daniel E.; Bartrand, Jonah AG

2016-01-01

We report results of measurements of isotopic ratios obtained with atom probe tomography on U3O8 reference materials certified for their isotopic abundances of uranium. The results show good agreement with the certified values. High backgrounds due to tails from adjacent peaks complicate the measurement of the integrated peak areas as well as the fact that only oxides of uranium appear in the spectrum, the most intense of which is doubly charged. In addition, lack of knowledge of other instrumental parameters, such as the dead time, may bias the results. Isotopic ratio measurements can be performed at the nanometer-scale with themore » expectation of sensible results. The abundance sensitivity and mass resolving power of the mass spectrometer are not sufficient to compete with magnetic-sector instruments but are not far from measurements made by ToF-SIMS of other isotopic systems. The agreement of the major isotope ratios is more than sufficient to distinguish most anthropogenic compositions from natural.« less

Spacecraft measurements of the elemental and isotopic composition of solar energetic particles

NASA Technical Reports Server (NTRS)

Mewaldt, R. A.

1980-01-01

Within the past few years, instruments flown on satellites and space probes have made significant progress in measuring the elemental and isotopic composition of energetic heavy nuclei accelerated in solar flares. These new observations are discussed, focusing on: (1) the energy dependence of the elemental composition at energies not greater than 1 MeV/nucleon; (2) flare to flare variations in the composition; and (3) comparisons of the average solar particle abundances (Z not less than 2 and not greater than 28) with other measures of the solar composition, including photospheric, coronal, and solar wind observations. These comparisons have led to the suggestion that solar flares sample the composition of the corona. Isotopic measurements of heavy solar flare nuclei have recently added a new dimension to these studies. In particular, the isotopic composition of solar flare neon has been found to be significantly different from that measured in the solar wind, but consistent with the meteoritic component neon-A.

Mass spectrometric measurements of the isotopic anatomies of molecules (Invited)

NASA Astrophysics Data System (ADS)

Eiler, J. M.; Krumwiede, D.; Schlueter, H.

2013-12-01

Site-specific and multiple isotopic substitutions in molecular structures potentially provide an extraordinarily rich set of constraints on their sources, conditions of formation, reaction and transport histories, and perhaps other issues. Examples include carbonate ';clumped isotope' thermometry, clumped isotope measurements of CO2, O2, and, recently, methane, ethane and N2O; site-specific 15N measurements in N2O and 13C and D analyses of fatty acids, sugars, cellulose, food products, and, recently, n-alkanes. Extension of the principles behind these tools to the very large number of isotopologues of complex molecules could potentially lead to new uses of isotope chemistry, similar to proteomics, metabolomics and genomics in their complexity and depth of detail (';isotomics'?). Several technologies are potentially useful for this field, including ';SNIF-NMR', gas source mass spectrometry and IR absorption spectroscopy. However, all well established methods have restrictive limits in the sizes of samples, types of analyzes, and the sorts of isotopologues that can be measured with useful precision. We will present an overview of several emerging instruments and techniques of high-resolution gas source mass spectrometry that may enable study of a large proportion of the isotopologues of a wide range of volatile and semi-volatile compounds, including many organics, with precisions and sample sizes suitable for a range of applications. A variety of isotopologues can be measured by combining information from the Thermo 253 Ultra (a new high resolution, multi-collector gas source mass spectrometer) and the Thermo DFS (a very high resolution single collector, but used here on a novel mode to achieve ~per mil precision ratio measurements), sometimes supplemented by conventional bulk isotopic measurements. It is possible to design methods in which no one of these sources of data meaningfully constrain abundances of specific isotopologues, but their combination fully and

Measuring Room Area or Volume Electronically

NASA Technical Reports Server (NTRS)

Kavaya, M. J.

1987-01-01

Area- and volume-measuring instrument hand-held or mounted on tripod. Instrument rapidly measures distances to walls, ceiling, or floor at many viewing angles and automatically computes area or volume of room. Results obtained rapidly with minimal effort.

Oxygen Isotope Measurements of a Rare Murchison Type A CAI and Its Rim

NASA Technical Reports Server (NTRS)

Matzel, J. E. P.; Simon, J. I.; Hutcheon, I. D.; Jacobsen, B.; Simon, S. B.; Grossman, L.

2013-01-01

Ca-, Al-rich inclusions (CAIs) from CV chondrites commonly show oxygen isotope heterogeneity among different mineral phases within individual inclusions reflecting the complex history of CAIs in both the solar nebula and/or parent bodies. The degree of isotopic exchange is typically mineral-specific, yielding O-16-rich spinel, hibonite and pyroxene and O-16-depleted melilite and anorthite. Recent work demonstrated large and systematic variations in oxygen isotope composition within the margin and Wark-Lovering rim of an Allende Type A CAI. These variations suggest that some CV CAIs formed from several oxygen reservoirs and may reflect transport between distinct regions of the solar nebula or varying gas composition near the proto-Sun. Oxygen isotope compositions of CAIs from other, less-altered chondrites show less intra-CAI variability and 16O-rich compositions. The record of intra-CAI oxygen isotope variability in CM chondrites, which commonly show evidence for low-temperature aqueous alteration, is less clear, in part because the most common CAIs found in CM chondrites are mineralogically simple (hibonite +/- spinel or spinel +/- pyroxene) and are composed of minerals less susceptible to O-isotopic exchange. No measurements of the oxygen isotope compositions of rims on CAIs in CM chondrites have been reported. Here, we present oxygen isotope data from a rare, Type A CAI from the Murchison meteorite, MUM-1. The data were collected from melilite, hibonite, perovskite and spinel in a traverse into the interior of the CAI and from pyroxene, melilite, anorthite, and spinel in the Wark-Lovering rim. Our objectives were to (1) document any evidence for intra-CAI oxygen isotope variability; (2) determine the isotopic composition of the rim minerals and compare their composition(s) to the CAI interior; and (3) compare the MUM-1 data to oxygen isotope zoning profiles measured from CAIs in other chondrites.

High-precision measurement of (186)Os/(188)Os and (187)Os/(188)Os: isobaric oxide corrections with in-run measured oxygen isotope ratios.

PubMed

Chu, Zhu-Yin; Li, Chao-Feng; Chen, Zhi; Xu, Jun-Jie; Di, Yan-Kun; Guo, Jing-Hui

2015-09-01

We present a novel method for high precision measurement of (186)Os/(188)Os and (187)Os/(188)Os ratios, applying isobaric oxide interference correction based on in-run measurements of oxygen isotopic ratios. For this purpose, we set up a static data collection routine to measure the main Os(16)O3(-) ion beams with Faraday cups connected to conventional 10(11) amplifiers, and (192)Os(16)O2(17)O(-) and (192)Os(16)O2(18)O(-) ion beams with Faraday cups connected to 10(12) amplifiers. Because of the limited number of Faraday cups, we did not measure (184)Os(16)O3(-) and (189)Os(16)O3(-) simultaneously in-run, but the analytical setup had no significant influence on final (186)Os/(188)Os and (187)Os/(188)Os data. By analyzing UMd, DROsS, an in-house Os solution standard, and several rock reference materials, including WPR-1, WMS-1a, and Gpt-5, the in-run measured oxygen isotopic ratios were proven to present accurate Os isotopic data. However, (186)Os/(188)Os and (187)Os/(188)Os data obtained with in-run O isotopic compositions for the solution standards and rock reference materials show minimal improvement in internal and external precision, compared to the conventional oxygen correction method. We concluded that, the small variations of oxygen isotopes during OsO3(-) analytical sessions are probably not the main source of error for high precision Os isotopic analysis. Nevertheless, use of run-specific O isotopic compositions is still a better choice for Os isotopic data reduction and eliminates the requirement of extra measurements of the oxygen isotopic ratios.

Potassium Stable Isotopic Compositions Measured by High-Resolution MC-ICP-MS

NASA Technical Reports Server (NTRS)

Morgan, Leah E.; Lloyd, Nicholas S.; Ellam, Robert M.; Simon, Justin I.

2012-01-01

Potassium isotopic (K-41/K-39) compositions are notoriously difficult to measure. TIMS measurements are hindered by variable fractionation patterns throughout individual runs and too few isotopes to apply an internal spike method for instrumental mass fractionation corrections. Internal fractionation corrections via the K-40/K-39 ratio can provide precise values but assume identical K-40/K-39 ratios (e.g. 0.05% (1sigma) in [1]); this is appropriate in some cases (e.g. identifying excess K-41) but not others (e.g., determining mass fractionation effects and metrologically traceable isotopic abundances). SIMS analyses have yielded measurements with 0.25% precisions (1sigma) [2]. ICP-MS analyses are significantly affected by interferences from molecular species such as Ar-38H(+) and Ar-40H(+) and instrument mass bias. Single collector ICP-MS instruments in "cold plasma" mode have yielded uncertainties as low as 2% (1sigma, e.g. [3]). Although these precisions may be acceptable for some concentration determinations, they do not resolve isotopic variation in terrestrial materials. Here we present data from a series of measurements made on the Thermo Scientific NEPTUNE Plus multi-collector ICP-MS that demonstrate the ability to make K-41/K-39 ratio measurements with 0.07% precisions (1sigma). These data, collected on NIST K standards, indicate the potential for MC-ICP-MS measurements to look for K isotopic variations at the sub-permil level. The NEPTUNE Plus can sufficiently resolve 39K and 41K from the interfering 38ArH+ and 40ArH+ peaks in wet cold plasma and high-resolution mode. Measurements were made on small but flat, interference-free, plateaus (ca. 50 ppm by mass width for K-41). Although ICP-MS does not yield accurate K-41/K-39 values due to significant instrumental mass fractionation (ca. 6%), this bias can be sufficiently stable over the time required for several measurements so that relative K-41/K-39 values can be precisely determined via sample

A technique for fast and accurate measurement of hand volumes using Archimedes' principle.

PubMed

Hughes, S; Lau, J

2008-03-01

A new technique for measuring hand volumes using Archimedes principle is described. The technique involves the immersion of a hand in a water container placed on an electronic balance. The volume is given by the change in weight divided by the density of water. This technique was compared with the more conventional technique of immersing an object in a container with an overflow spout and collecting and weighing the volume of overflow water. The hand volume of two subjects was measured. Hand volumes were 494 +/- 6 ml and 312 +/- 7 ml for the immersion method and 476 +/- 14 ml and 302 +/- 8 ml for the overflow method for the two subjects respectively. Using plastic test objects, the mean difference between the actual and measured volume was -0.3% and 2.0% for the immersion and overflow techniques respectively. This study shows that hand volumes can be obtained more quickly than the overflow method. The technique could find an application in clinics where frequent hand volumes are required.

Precision mass measurements of neutron-rich Co isotopes beyond N =40

NASA Astrophysics Data System (ADS)

Izzo, C.; Bollen, G.; Brodeur, M.; Eibach, M.; Gulyuz, K.; Holt, J. D.; Kelly, J. M.; Redshaw, M.; Ringle, R.; Sandler, R.; Schwarz, S.; Stroberg, S. R.; Sumithrarachchi, C. S.; Valverde, A. A.; Villari, A. C. C.

2018-01-01

The region near Z =28 and N =40 is a subject of great interest for nuclear structure studies due to spectroscopic signatures in 68Ni suggesting a subshell closure at N =40 . Trends in nuclear masses and their derivatives provide a complementary approach to shell structure investigations via separation energies. Penning trap mass spectrometry has provided precise measurements for a number of nuclei in this region; however, a complete picture of the mass surfaces has so far been limited by the large uncertainty remaining for nuclei with N >40 along the iron (Z =26 ) and cobalt (Z =27 ) chains because these species are not available from traditional isotope separator online rare isotope facilities. The Low-Energy Beam and Ion Trap Facility at the National Superconducting Cyclotron Laboratory is the first and only Penning trap mass spectrometer coupled to a fragmentation facility and therefore presents the unique opportunity to perform precise mass measurements of these elusive isotopes. Here we present the first Penning trap measurements of Co,6968, carried out at this facility. Some ambiguity remains as to whether the measured values are ground-state or isomeric-state masses. A detailed discussion is presented to evaluate this question and to motivate future work. In addition, we perform ab initio calculations of ground-state and two-neutron separation energies of cobalt isotopes with the valence-space in-medium similarity renormalization group approach based on a particular set of two- and three-nucleon forces that predict saturation in infinite matter. We discuss the importance of these measurements and calculations for understanding the evolution of nuclear structure near 68Ni.

Review and Evaluation of Hand-Arm Coordinate Systems for Measuring Vibration Exposure, Biodynamic Responses, and Hand Forces.

PubMed

Dong, Ren G; Sinsel, Erik W; Welcome, Daniel E; Warren, Christopher; Xu, Xueyan S; McDowell, Thomas W; Wu, John Z

2015-09-01

The hand coordinate systems for measuring vibration exposures and biodynamic responses have been standardized, but they are not actually used in many studies. This contradicts the purpose of the standardization. The objectives of this study were to identify the major sources of this problem, and to help define or identify better coordinate systems for the standardization. This study systematically reviewed the principles and definition methods, and evaluated typical hand coordinate systems. This study confirms that, as accelerometers remain the major technology for vibration measurement, it is reasonable to standardize two types of coordinate systems: a tool-based basicentric (BC) system and an anatomically based biodynamic (BD) system. However, these coordinate systems are not well defined in the current standard. Definition of the standard BC system is confusing, and it can be interpreted differently; as a result, it has been inconsistently applied in various standards and studies. The standard hand BD system is defined using the orientation of the third metacarpal bone. It is neither convenient nor defined based on important biological or biodynamic features. This explains why it is rarely used in practice. To resolve these inconsistencies and deficiencies, we proposed a revised method for defining the realistic handle BC system and an alternative method for defining the hand BD system. A fingertip-based BD system for measuring the principal grip force is also proposed based on an important feature of the grip force confirmed in this study.

Combination of hand-held probe and microscopy for fluorescence guided surgery in the brain tumor marginal zone.

PubMed

Richter, Johan C O; Haj-Hosseini, Neda; Hallbeck, Martin; Wårdell, Karin

2017-06-01

Visualization of the tumor is crucial for differentiating malignant tissue from healthy brain during surgery, especially in the tumor marginal zone. The aim of the study was to introduce a fluorescence spectroscopy-based hand-held probe (HHF-probe) for tumor identification in combination with the fluorescence guided resection surgical microscope (FGR-microscope), and evaluate them in terms of diagnostic performance and practical aspects of fluorescence detection. Eighteen operations were performed on 16 patients with suspected high-grade glioma. The HHF-probe and the FGR-microscope were used for detection of protoporphyrin (PpIX) fluorescence induced by 5-aminolevulinic acid (5-ALA) and evaluated against histopathological analysis and visual grading done through the FGR-microscope by the surgeon. A ratio of PpIX fluorescence intensity to the autofluorescence intensity (fluorescence ratio) was used to quantify the spectra detected by the probe. Fluorescence ratio medians (range 0 - 40) measured by the probe were related to the intensity of the fluorescence in the FGR-microscope, categorized as "none" (0.3, n=131), "weak" (1.6, n=34) and "strong" (5.4, n=28). Of 131 "none" points in the FGR-microscope, 88 (67%) exhibited fluorescence with the HHF-probe. For the tumor marginal zone, the area under the receiver operator characteristics (ROC) curve was 0.49 for the FGR-microscope and 0.65 for the HHF-probe. The probe was integrated in the established routine of tumor resection using the FGR-microscope. The HHF-probe was superior to the FGR-microscope in sensitivity; it detected tumor remnants after debulking under the FGR-microscope. The combination of the HHF-probe and the FGR-microscope was beneficial especially in the tumor marginal zone. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.

[Measurements of stable isotopes in atmospheric CO2 and H2O by open-path Fourier transform infrared spectrometry].

PubMed

Wang, Wei; Liu, Wen-Qing; Zhang, Tian-Shu

2013-08-01

The development of spectroscopic techniques has offered continuous measurement of stable isotopes in the ambient air. The method of measuring environmental stable isotopes based on Fourier transform infrared spectrometry (FTIR) is described. In order to verify the feasibility of the method for continuous measurement of the stable isotopes, an open-path FTIR system was used to measure stable isotopes of CO2 and H2O in ambient air directly in a seven-day field experiment, including 12CO2, 3CO2, H2 16O and HD16 O. Also, the time course of carbon isotopic ratio delta13 C and deuterium isotope composition deltaD was calculated. The measurement precision is about 1.08 per thousand for delta13 C and 1.32 per thousand for deltaD. The measured stable isotopes of CO2 and H2O were analyzed on different time scales by Keeling plot methods, and the deuterium isotopic ratios of evapotranspiration were determined. The results of the field experiment demonstrate the potential of the open-path FTIR system for continuous measurement of stable isotopes in the air.

Eddy Covariance measurements of stable isotopes (δD and δ18O) in water vapor

NASA Astrophysics Data System (ADS)

Braden-Behrens, Jelka; Knohl, Alexander

2017-04-01

Stable isotopes are a promising tool to enhance our understanding of ecosystem gas exchanges. Studying 18O and 2H in water vapour (H2Ov) can e.g. help partitioning evapotranspiration into its components. With recent developments in laser spectroscopy direct Eddy Covariance (EC) measurements for investigating fluxes of stable isotopologues became feasible. So far very few case studies have applied the EC method to measure stable isotopes in water vapor. We continuously measure fluxes of water vapor isotopologues with the EC method in a managed beech forest in Thuringia, Germany, since autumn 2015 using the following setup: An off-axis integrated cavity output water vapor isotope analyzer (WVIA, Los Gatos Research. Inc, USA) measures the water vapour concentration and its isotopic composition (δD and δ18O). The instrument, that was optimized for high flow rates (app. 4slpm) to generate high frequency (2Hz) measurements, showed sufficient precision with Allan Deviations of app. 0.12 ‰ for δD and 0.06 ‰ for δ18O for averaging periods of 100s. The instrument was calibrated hourly using a high-flow optimized version of the water vapor isotope standard source (WVISS, Los Gatos Research. Inc, USA) that provides water vapor with known isotopic composition for a large range of different concentrations. Our calibration scheme includes a near continuous concentration range calibration instead of a simple 2 or 3-point calibration to face the analyzers strong concentration dependency within a range of app. 6 000 to 16 000 ppm in winter and app. 8 000 to 23 000 ppm in summer. In the used setup, the high-flow and high-frequency optimized water vapor isotope analyzer (WVIA) showed suitable characteristics (Allan deviation and spectral energy distribution) to perform Eddy covariance measurements of stable isotopes in H2Ov. Thus, this novel instrument for EC measurements of water vapor isotopologues provides a new opportunity for studying the hydrological cycle in long

Manual muscle testing and hand-held dynamometry in people with inflammatory myopathy: An intra- and interrater reliability and validity study

PubMed Central

Baschung Pfister, Pierrette; Sterkele, Iris; Maurer, Britta; de Bie, Rob A.; Knols, Ruud H.

2018-01-01

Manual muscle testing (MMT) and hand-held dynamometry (HHD) are commonly used in people with inflammatory myopathy (IM), but their clinimetric properties have not yet been sufficiently studied. To evaluate the reliability and validity of MMT and HHD, maximum isometric strength was measured in eight muscle groups across three measurement events. To evaluate reliability of HHD, intra-class correlation coefficients (ICC), the standard error of measurements (SEM) and smallest detectable changes (SDC) were calculated. To measure reliability of MMT linear Cohen`s Kappa was computed for single muscle groups and ICC for total score. Additionally, correlations between MMT8 and HHD were evaluated with Spearman Correlation Coefficients. Fifty people with myositis (56±14 years, 76% female) were included in the study. Intra-and interrater reliability of HHD yielded excellent ICCs (0.75–0.97) for all muscle groups, except for interrater reliability of ankle extension (0.61). The corresponding SEMs% ranged from 8 to 28% and the SDCs% from 23 to 65%. MMT8 total score revealed excellent intra-and interrater reliability (ICC>0.9). Intrarater reliability of single muscle groups was substantial for shoulder and hip abduction, elbow and neck flexion, and hip extension (0.64–0.69); moderate for wrist (0.53) and knee extension (0.49) and fair for ankle extension (0.35). Interrater reliability was moderate for neck flexion (0.54) and hip abduction (0.44); fair for shoulder abduction, elbow flexion, wrist and ankle extension (0.20–0.33); and slight for knee extension (0.08). Correlations between the two tests were low for wrist, knee, ankle, and hip extension; moderate for elbow flexion, neck flexion and hip abduction; and good for shoulder abduction. In conclusion, the MMT8 total score is a reliable assessment to consider general muscle weakness in people with myositis but not for single muscle groups. In contrast, our results confirm that HHD can be recommended to evaluate

Purdue Rare Isotope Measurement Laboratory

NASA Astrophysics Data System (ADS)

Caffee, M.; Elmore, D.; Granger, D.; Muzikar, P.

2002-12-01

The Purdue Rare Isotope Measurement Laboratory (PRIME Lab) is a dedicated research and service facility for accelerator mass spectrometry. AMS is an ultra-sensitive analytical technique used to measure low levels of long-lived cosmic-ray-produced and anthropogenic radionuclides, and rare trace elements. We measure 10Be (T1/2 = 1.5 My), 26Al (.702 My), 36Cl (.301 My), and 129I (16 My), in geologic samples. Applications include dating the cosmic-ray-exposure time of rocks on Earth's surface, determining rock and sediment burial ages, measuring the erosion rates of rocks and soils, and tracing and dating ground water. We perform sample preparation and separation chemistries for these radio-nuclides for our internal research activities and for those external researchers not possessing this capability. Our chemical preparation laboratories also serve as training sites for members of the geoscience community developing these techniques at their institutions. Research at Purdue involves collaborators among members of the Purdue Departments of Physics, Earth and Atmospheric Sciences, Chemistry, Agronomy, and Anthropology. We also collaborate and serve numerous scientists from other institutions. We are currently in the process of modernizing the facility with the goals of higher precision for routinely measured radio-nuclides, increased sample throughput, and the development of new measurement capabilities for the geoscience community.

Portable computing for taking part of the lab to the sample types of applications. From hand held personal digital assistants to smart phones for mobile spectrometry

NASA Astrophysics Data System (ADS)

Weagant, Scott; Karanassios, Vassili

2015-06-01

The use of portable hand held computing devices for the acquisition of spectrochemical data is briefly discussed using examples from the author's laboratory. Several network topologies are evaluated. At present, one topology that involves a portable computing device for data acquisition and spectrometer control and that has wireless access to the internet at one end and communicates with a smart phone at the other end appears to be better suited for "taking part of the lab to the sample" types of applications. Thus, spectrometric data can be accessed from anywhere in the world.

Characterization of a new candidate isotopic reference material for natural Pb using primary measurement method.

PubMed

Nonose, Naoko; Suzuki, Toshihiro; Shin, Ki-Cheol; Miura, Tsutomu; Hioki, Akiharu

2017-06-29

A lead isotopic standard solution with natural abundance has been developed by applying a mixture of a solution of enriched 208 Pb and a solution of enriched 204 Pb ( 208 Pb- 204 Pb double spike solution) as bracketing method. The amount-of-substance ratio of 208 Pb: 204 Pb in this solution is accurately measured by applying EDTA titrimetry, which is one of the primary measurement methods, to each enriched Pb isotope solution. Also metal impurities affecting EDTA titration and minor lead isotopes contained in each enriched Pb isotope solution are quantified by ICP-SF-MS. The amount-of-substance ratio of 208 Pb: 204 Pb in the 208 Pb- 204 Pb double spike solution is 0.961959 ± 0.000056 (combined standard uncertainty; k = 1). Both the measurement of lead isotope ratios in a candidate isotopic standard solution and the correction of mass discrimination in MC-ICP-MS are carried out by coupling of a bracketing method with the 208 Pb- 204 Pb double spike solution and a thallium internal addition method, where thallium solution is added to the standard and the sample. The measured lead isotope ratios and their expanded uncertainties (k = 2) in the candidate isotopic standard solution are 18.0900 ± 0.0046 for 206 Pb: 204 Pb, 15.6278 ± 0.0036 for 207 Pb: 204 Pb, 38.0626 ± 0.0089 for 208 Pb: 204 Pb, 2.104406 ± 0.00013 for 208 Pb: 206 Pb, and 0.863888 ± 0.000036 for 207 Pb: 206 Pb. The expanded uncertainties are about one half of the stated uncertainty for NIST SRM 981, for 208 Pb: 204 Pb, 207 Pb: 204 Pb and 206 Pb: 204 Pb, or one eighth, for 208 Pb: 206 Pb and 207 Pb: 206 Pb, The combined uncertainty consists of the uncertainties due to lead isotope ratio measurements and the remaining time-drift effect of mass discrimination in MC-ICP-MS, which is not removed by the coupled correction method. In the measurement of 208 Pb: 204 Pb, 207 Pb: 204 Pb and 206 Pb: 204 Pb, the latter contribution is two or three times larger than the former. When the coupling of

Carbon Isotopic Measurements of Amino Acids in Stardust-Returned Samples

NASA Technical Reports Server (NTRS)

Elsila, Jamie

2009-01-01

NASA's Stardust spacecraft returned to Earth samples from comet 81P/Wild 2 in January 2006. Preliminary examinations revealed the presence of a suite of organic compounds including several amines and amino acids, but the origin of these compounds could not be identified. Here, we present the carbon isotopic ratios of glycine and e-aminocaproic acid (EACA), the two most abundant amino acids, in Stardust-returned foil samples measured by gas chromatography-combustion-isotope ratio mass spectrometry coupled with quadrupole mass spectrometry (GC-CAMS/IRMS).

An analysis of the input-output properties of neuroprosthetic hand grasps.

PubMed

Memberg, W D; Crago, P E

2000-01-01

We measured the input-output properties of the hand grasps of 14 individuals with tetraplegia at the C5/C6 level who had received an implanted upper limb neuroprosthesis. The data provide a quantitative description of grasp-opening and grasp-force control with neuroprosthetic hand grasp systems. Static properties were estimated by slowly ramping the command (input) from 0 to 100%. A hand-held sensor monitored the outputs: grasp force and grasp opening. Trials were performed at different wrist positions, with two different-sized objects being held, and with both grasp modes (lateral and palmar grasps). Larger forces were produced when grasping larger objects, and greater opening was achieved with the wrist in flexion. Although active grasp force increased with wrist extension, it was not significant statistically. Lateral grasp produced larger forces than the palmar grasp. The command range can be divided into a portion that controls grasp opening and a portion that controls grasp force. The portion controlling force increased with spacer size, but did not depend significantly on grasp mode or wrist position. The force-command relationships were more linear than the position-command relationships. Grasp opening decreased significantly over a one-year period, while no significant change in grasp force was observed. These quantitative descriptions of neuroprosthetic hand grasps under varying conditions provide useful information about output capabilities that can be used to gauge the effectiveness of different control schemes and to design future control systems.

Paired measurements of K and Mg isotopes and clay authigenesis in marine sediments

NASA Astrophysics Data System (ADS)

Santiago Ramos, D. P.; Dunlea, A. G.; Higgins, J. A.

2016-12-01

Despite its importance as a major sink for seawater K and Mg, estimates of clay authigenesis in marine sediments remain poorly constrained. Previous work on Mg isotope fractionation during clay formation has revealed a preferential uptake of 26Mg, yielding authigenic clay products with potentially distinct δ26Mg compared to the detrital component. In a similar manner, we aim to quantify the K isotope fractionation during authigenic clay formation and to use paired δ26Mg and δ41K measurements as proxies for the identification and quantification of authigenic clays in shallow and deep marine sedimentary systems. To better understand the behavior of paired Mg and K isotopes during authigenic clay formation in marine sediments, we measured δ26Mg and δ41K values of pore-fluids and sediments from ODP/IODP sites 1052, U1395, U1403 and U1366. We find that while pore-fluid K concentrations at sites 1052, U1395 and U1403 all decline with depth, δ41K profiles differ significantly. These differences might be a result of a complex interplay between clay authigenesis, sedimentation rate, and fractionation of K isotopes during diffusion. Results from 1-D diffusion-advection-reaction models suggest that, in contrast to Mg, diffusion may play an important role in determining the overall K isotope fractionation during clay authigenesis in sites with low-sedimentation rates. Sites with high sedimentation rates may act as close systems where diffusion is negligible. In such cases, K uptake can be modeled as a Rayleigh distillation process and K isotope fractionation can be estimated. Measurements of δ26Mg and δ41K of pore-fluids from site U1395 and bulk sediments from U1366 suggest that paired measurements of these isotopic systems in siliciclastic marine sediments can provide new insights into rates of marine clay authigenesis, a globally important but understudied component of many geochemical cycles.

High temporal resolution measurements of the isotopic composition of CH4 at the Lutjewad station, The Netherlands

NASA Astrophysics Data System (ADS)

Röckmann, Thomas; van der Veen, Carina; Chen, Huilin; Scheeren, Bert

2017-04-01

Isotope measurements can help constraining the atmospheric budget of the greenhouse gas methane (CH4) because different sources emit CH4 with slightly different isotopic composition. In the past, high precision isotope measurements have primarily been carried out by isotope ratio mass spectrometry on flask samples that are usually collected at relatively low temporal resolution. We have recently developed a fully automated gas chromatography - isotope ratio mass spectrometry system (GC-IRMS) for autonomous and unattended CH4 isotope measurements (δD and δ13C) in the field. The first deployment at the Cabauw Experimental Site for Atmospheric Research (CESAR) indicated that CH4 emissions from fossil fuel sources are overestimated in this region [1]. To further exploit the potential of this approach, the in situ system has been installed in November 2016 at the Lutjewad atmospheric monitoring and sampling site in the North of the Netherlands. This site is expected to sample also emissions from the large Groningen gas fields. The isotope measurements are expected to allow distinguishing these emissions from the agricultural emissions, which are also strong in this region. We will present the results from these ongoing measurements of δD and δ13C in CH4.. 1. Röckmann, T., et al., In situ observations of the isotopic composition of methane at the Cabauw tall tower site, Atmos. Chem. Phys., 2016. 16: 10469-10487.

Stable Isotope Measurements of Carbon Dioxide, Methane, and Hydrogen Sulfide Gas Using Frequency Modulation Spectroscopy

NASA Astrophysics Data System (ADS)

Nowak-Lovato, K.

2014-12-01

Seepage from enhanced oil recovery, carbon storage, and natural gas sites can emit trace gases such as carbon dioxide, methane, and hydrogen sulfide. Trace gas emission at these locations demonstrate unique light stable isotope signatures that provide information to enable source identification of the material. Light stable isotope detection through surface monitoring, offers the ability to distinguish between trace gases emitted from sources such as, biological (fertilizers and wastes), mineral (coal or seams), or liquid organic systems (oil and gas reservoirs). To make light stable isotope measurements, we employ the ultra-sensitive technique, frequency modulation spectroscopy (FMS). FMS is an absorption technique with sensitivity enhancements approximately 100-1000x more than standard absorption spectroscopy with the advantage of providing stable isotope signature information. We have developed an integrated in situ (point source) system that measures carbon dioxide, methane and hydrogen sulfide with isotopic resolution and enhanced sensitivity. The in situ instrument involves the continuous collection of air and records the stable isotope ratio for the gas being detected. We have included in-line flask collection points to obtain gas samples for validation of isotopic concentrations using our in-house isotope ratio mass spectroscopy (IRMS). We present calibration curves for each species addressed above to demonstrate the sensitivity and accuracy of the system. We also show field deployment data demonstrating the capabilities of the system in making live dynamic measurements from an active source.

Absolute measurements and certified reference material for iron isotopes using multiple-collector inductively coupled mass spectrometry.

PubMed

Zhou, Tao; Zhao, Motian; Wang, Jun; Lu, Hai

2008-01-01

Two enriched isotopes, 99.94 at.% 56Fe and 99.90 at.% 54Fe, were blended under gravimetric control to prepare ten synthetic isotope samples whose 56Fe isotope abundances ranged from 95% to 20%. For multiple-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) measurements typical polyatomic interferences were removed by using Ar and H2 as collision gas and operating the MC-ICP-MS system in soft mode. Thus high-precision measurements of the Fe isotope abundance ratios were accomplished. Based on the measurement of the synthetic isotope abundance ratios by MC-ICP-MS, the correction factor for mass discrimination was calculated and the results were in agreement with results from IRMM014. The precision of all ten correction factors was 0.044%, indicating a good linearity of the MC-ICP-MS method for different isotope abundance ratio values. An isotopic reference material was certified under the same conditions as the instrument was calibrated. The uncertainties of ten correction factors K were calculated and the final extended uncertainties of the isotopic certified Fe reference material were 5.8363(37) at.% 54Fe, 91.7621(51) at.% 56Fe, 2.1219(23) at.% 57Fe, and 0.2797(32) at.% 58Fe.

Bio-electrical impedance spectroscopy: alternatives for the conventional hand-to-foot measurements.

PubMed

Cox-Reijven, P L M; Van Kreel, B; Soeters, P B

2002-04-01

Bio-impedance spectroscopy (BIS) is a very attractive method for measuring body composition. The standard method measures impedance from hand to foot. However, in patients a hand or foot is not always accessible. In these cases alternative methods would be helpful. The objective of this study was to compare BIS measurements from hand to foot (HF) with foot to foot (FF) and hand to hand (HH) measurements as alternatives. Aims were firstly, to assess the relationship between resistance (R) values measured by the different methods, secondly, to study the influence of body geometry on this relationship and lastly, to assess the predictive capacity of the methods for measuring body fluid volumes. In 53 subjects with different degrees of obesity (mean BMI = 38; SD = 9 kg/m(2)) three BIS measurements were performed from HF, HH and FF with a Xitron 4000B machine. Resistances of extracellular (Recw) and intracellular water (Ricw) were extrapolated by fitting the data to a Cole-Cole plot. Total body water (TBW) and extracellular water (ECW) were measured by deuterium and bromide dilution respectively. Intracellular water (ICW) was calculated as TBW-ECW. Anthropometric measurements, including length and circumference of limbs and trunk, were performed as measures for body geometry. The Recw, Ricw and R50 values of HF measurements could be accurately described as a function of the Recw, Ricw and R50 values of HH or FF measurements. The relative circumference of arms and legs and the length of the trunk influenced the relationship between R values of the three different measurements. The degree of overweight did not affect this relationship. The precision of the predictions of TBW, ECW and ICW based on R values of the HH measurements were comparable with the traditional HF measurements while the FF measurements gave slightly less accurate results. Under circumstances where total body BIS measurements cannot be performed, FF or HH measurements may be used as alternatives

First total-absorption spectroscopy measurement on the neutron-rich Cu isotopes

NASA Astrophysics Data System (ADS)

Naqvi, F.; Spyrou, A.; Liddick, S. N.; Larsen, A. C.; Guttormsen, M.; Bleuel, D. L.; Campo, L. C.; Couture, A.; Crider, B. P.; Dombos, A. C.; Ginter, T.; Lewis, R.; Mosby, S.; Perdikakis, G.; Prokop, C. P.; Quinn, S. J.; Renstrom, T.; Rubio, B.; Siem, S.

2015-10-01

The first beta-decay studies of 73-71Cu isotopes using the Total Absorption Spectroscopy (TAS) will be reported. The Cu isotopes have one proton outside the Z = 28 shell and hence are good candidates to probe the single-particle structure in the region.Theories predict weakening of the Z = 28 shell gap due to the tensor interaction between the valence πν single-particle orbitals. Comparing the beta-decay strength distributions in the daughter Zn isotopes to the theoretical calculations will provide a stringent test of the predictions. The experiment was performed at the National Superconducting Cyclotron Laboratory (NSCL) employing the TAS technique with the Summing NaI(Tl) detector, while beta decays were measured in the NSCL beta-counting system. The experimentally obtained total absorption spectra for the neutron-rich Cu isotopes will be presented and the implications of the extracted beta-feeding intensities will be discussed.

Spectroscopic Measurement of LEAD-204 Isotope Shift and LEAD-205 Nuclear Spin.

NASA Astrophysics Data System (ADS)

Schonberger, Peter

The isotope shift of ('204)Pb and the nuclear spin of 1.4 x 10('7)-y ('205)Pb was determined from a high -resolution optical measurement of the 6p('2) ('3)P(,o) -6p7s('3)P(,1)('o) 283.3-nm resonance line. The value of the shift, relative to ('208)Pb is -140.2(8) x 10('-3)cm(' -1), the negative sign indicating a shift to lower wave numbers. The precision is 3-4 times greater than that of previous measurements. The spin of ('205)Pb l = 5/2 was obtained from the measurement of the relative intensities of its three hyperfine components. This method of absorption spectroscopy determination of ground state nuclear spin is applicable to any stable or longlived isotope. High resolution optical absorption spectra were obtained with a 25.4cm diffraction grating in a 9.1m focal length Czerny-Turner spectrometer. A signal-averaging scanning technique was used to record the spectra. Increased precision in the isotope shift measurement was attained by using separated isotope samples of ('204)Pb and ('207)Pb. A controlled amount of the later was incorporated in the absorption cell to provide internal calibration by its 6p7s ('3)P(,1)('o) hfs separation. Absorption spectra were recorded for several optical thicknesses of the absorber. A single spin value of increased precision was derived from the entire set of combined data.

Knee-laxity measurements examined by a left-hand- and a right-hand-dominant physiotherapist, in patients with anterior cruciate ligament injuries and healthy controls.

PubMed

Sernert, Ninni; Helmers, Janett; Kartus, Catarina; Ejerhed, Lars; Kartus, Jüri

2007-10-01

The purpose of the study was to analyse and compare KT-1000 knee laxity as examined by a left-hand- and a right-hand-dominant physiotherapist in a group of patients with an anterior cruciate ligament (ACL) injury and a group of patients, 2 years after ACL reconstruction. The other aim was to measure and analyse knee laxity in a group of persons without any known knee problems. A cross-sectional examination of two groups of patients pre-operatively and post-operatively after ACL reconstruction and examination of healthy controls on two different occasions was performed. Fifty-three patients who were scheduled for ACL reconstruction and 39 patients who attended a 2-year follow-up examination were included in the study. In the ACL-deficient group, 32 patients had a right-sided ACL injury and 21 patients a left-sided ACL injury. The corresponding figures in the post-operative group were 21 patients with a right-sided ACL injury and 18 patients with a left-sided ACL injury. Twenty-eight healthy persons without any known knee problems served as controls. One left-hand- and one right-hand-dominant experienced physiotherapist performed all the examinations. To be able to evaluate the intra and inter-reliability of the examiners the controls were examined at two occasions. The left-hand-dominant physiotherapist measured significantly higher absolute laxity values in the left knee, both injured and non-injured ones, compared with the right-hand-dominant physiotherapist. This was found irrespectively of whether the patients belonged to the ACL deficient or the post-operative group. In the healthy control group, the right-hand-dominant physiotherapist measured significantly higher knee-laxity values in the right knee compared with the left-hand-dominant physiotherapist. Correspondingly, the left-hand-dominant physiotherapist measured significantly higher knee laxity values in the left knee. We conclude that KT-1000 arthrometer laxity measurements can be affected by the hand

On the cross-sensitivity between water vapor mixing ratio and stable isotope measurements of in-situ analyzers

NASA Astrophysics Data System (ADS)

Parkes, Stephen; Wang, Lixin; McCabe, Matthew

2015-04-01

In recent years there has been an increasing amount of water vapor stable isotope data collected using in-situ instrumentation. A number of papers have characterized the performance of these in-situ analyzers and suggested methods for calibrating raw measurements. The cross-sensitivity of the isotopic measurements on the mixing ratio has been shown to be a major uncertainty and a variety of techniques have been suggested to characterize this inaccuracy. However, most of these are based on relating isotopic ratios to water vapor mixing ratios from in-situ analyzers when the mixing ratio is varied and the isotopic composition kept constant. An additional correction for the span of the isotopic ratio scale is then applied by measuring different isotopic standards. Here we argue that the water vapor cross-sensitivity arises from different instrument responses (span and offset) of the parent H2O isotope and the heavier isotopes, rather than spectral overlap that could cause a true variation in the isotopic ratio with mixing ratio. This is especially relevant for commercial laser optical instruments where absorption lines are well resolved. Thus, the cross-sensitivity determined using more conventional techniques is dependent on the isotopic ratio of the standard used for the characterization, although errors are expected to be small. Consequently, the cross-sensitivity should be determined by characterizing the span and zero offset of each isotope mixing ratio. In fact, this technique makes the span correction for the isotopic ratio redundant. In this work we model the impact of changes in the span and offset of the heavy and light isotopes and illustrate the impact on the cross-sensitivity of the isotopic ratios on water vapor. This clearly shows the importance of determining the zero offset for the two isotopes. The cross-sensitivity of the isotopic ratios on water vapor is then characterized by determining the instrument response for the individual isotopes for a

Intrarater reliability of goniometry and hand-held dynamometry for shoulder and elbow examinations in female team handball athletes and asymptomatic volunteers.

PubMed

Fieseler, Georg; Molitor, Thomas; Irlenbusch, Lars; Delank, Karl-Stefan; Laudner, Kevin G; Hermassi, Souhail; Schwesig, Rene

2015-12-01

To evaluate the intrarater reliability for examining active range of motion (ROM) and isometric strength of the shoulder and elbow among asymptomatic female team handball athletes and a control group using a manual goniometer and hand-held dynamometry (HHD). 22 female team handball athletes (age: 21.0 ± 3.7 years) and 25 volunteers (13 female, 12 male, age: 21.9 ± 1.24 years) participated to determine bilateral ROM for shoulder rotation and elbow flexion/extension, as well as isometric shoulder rotation and elbow flexion/extension strength. Subjects were assessed on two separate test sessions with 7 days between sessions. Relative (intraclass correlation coefficients (ICC) and standard error of measurement (SEM) reliability were calculated. Reliability for ROM and strength were good to excellent for both shoulders and groups (athletes: ICC = 0.94-0.97, SEM 1.07°-4.76 N, controls: ICC = 0.96-1.00, SEM = 0.00 N-4.48 N). Elbow measurements for both groups also showed good-to-excellent reliability (athletes: ICC = 0.79-0.97, SEM = 0.98°-5.94 N, controls: ICC = 0.87-1.00, SEM = 0.00 N-5.43 N). It is important to be able to reliably reproduce active ROM and isometric strength evaluations. Using a standardized testing position, goniometry and HHD are reliable instruments in the assessment of shoulder and elbow joint performance testing. We showed good-to-excellent reproducible results for male and female control subjects and female handball athletes, although the single parameters in ROM and strength were different for each group and between the shoulders and elbows.

Measurement of Enzyme Isotope Effects.

PubMed

Kholodar, Svetlana A; Ghosh, Ananda K; Kohen, Amnon

2017-01-01

Enzyme isotope effects, or the kinetic effects of "heavy" enzymes, refer to the effect of isotopically labeled protein residues on the enzyme's activity or physical properties. These effects are increasingly employed in the examination of the possible contributions of protein dynamics to enzyme catalysis. One hypothesis assumed that isotopic substitution of all 12 C, 14 N, and nonexchangeable 1 H by 13 C, 15 N, and 2 H, would slow down protein picosecond to femtosecond dynamics without any effect on the system's electrostatics following the Born-Oppenheimer approximation. It was suggested that reduced reaction rates reported for several "heavy" enzymes accords with that hypothesis. However, numerous deviations from the predictions of that hypothesis were also reported. Current studies also attempt to test the role of individual residues by site-specific labeling or by labeling a pattern of residues on activity. It appears that in several systems the protein's fast dynamics are indeed reduced in "heavy" enzymes in a way that reduces the probability of barrier crossing of its chemical step. Other observations, however, indicated that slower protein dynamics are electrostatically altered in isotopically labeled enzymes. Interestingly, these effects appear to be system dependent, thus it might be premature to suggest a general role of "heavy" enzymes' effect on catalysis. © 2017 Elsevier Inc. All rights reserved.

Precise and traceable carbon isotope ratio measurements by multicollector ICP-MS: what next?

PubMed

Santamaria-Fernandez, Rebeca

2010-06-01

This article reviews recent developments in the use of multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) to provide high-precision carbon isotope ratio measurements. MC-ICP-MS could become an alternative method to isotope ratio mass spectrometry (IRMS) for rapid carbon isotope ratio determinations in organic compounds and characterisation and certification of isotopic reference materials. In this overview, the advantages, drawbacks and potential of the method for future applications are critically discussed. Furthermore, suggestions for future improvements in terms of precision and sensitivity are made. No doubt, this is an exciting analytical challenge and, as such, hurdles will need to be cleared.

A hydrogen gas-water equilibration method produces accurate and precise stable hydrogen isotope ratio measurements in nutrition studies

USDA-ARS?s Scientific Manuscript database

Stable hydrogen isotope methodology is used in nutrition studies to measure growth, breast milk intake, and energy requirement. Isotope ratio MS is the best instrumentation to measure the stable hydrogen isotope ratios in physiological fluids. Conventional methods to convert physiological fluids to ...

Measurement of longitudinal sulfur isotopic variations by laser ablation MC-ICP-MS in single human hair strands.

PubMed

Santamaria-Fernandez, Rebeca; Giner Martínez-Sierra, Justo; Marchante-Gayón, J M; García-Alonso, J Ignacio; Hearn, Ruth

2009-05-01

A new method for the measurement of longitudinal variations of sulfur isotope amount ratios in single hair strands using a laser ablation system coupled to a multicollector inductively coupled plasma mass spectrometer (LA-MC-ICP-MS) is reported here for the first time. Ablation parameters have been optimized for the measurement of sulfur isotope ratios in scalp human hair strands of 80-120-microm thickness and different washing procedures have been evaluated. The repeatability of the method has been tested and the ability to measure sulfur isotopic variations in 1,000-microm-long hair segments has been evaluated. A horse hair sample previously characterized for carbon and nitrogen isotope ratios in an interlaboratory study has been characterized by LA-MC-ICP-MS to be used as an in-house standard for the bracketing of human hair strands. (34)S/(32)S isotope amount ratios have been measured and corrected for instrumental mass bias adopting the external standardization approach using National Institute of Standards and Technology (NIST) RM8553 and full uncertainty budgets have been calculated using the Kragten approach. Results are reported as both (34)S/(32)S isotope amount ratios and deltaS(V-CDT) values (sulfur isotopic differences relative to a reference sample expressed in the Vienna Canyon Diablo Troilite (V-CDT) scale) calculated using NIST RM8553, NIST RM8554, and NIST RM8556 to anchor results to the V-CDT scale. The main advantage of the new method versus conventional gas source isotope ratio mass spectrometry measurements is that longitudinal variations in sulfur isotope amount ratios can be resolved. Proof of concept is shown with human scalp hair strands from three individuals, two UK residents and one traveler (long periods of time abroad). The method enables monitoring of longitudinal isotope ratio variations in single hair strands. Absolute ratios are reported and delta(34)S(V-CDT) values are plotted for comparison. Slight variations of <1.2 per

Natural Ca Isotope Composition of Urine as a Rapid Measure of Bone Mineral Balance

NASA Astrophysics Data System (ADS)

Skulan, J.; Gordon, G. W.; Morgan, J.; Romaniello, S. J.; Smith, S. M.; Anbar, A. D.

2011-12-01

Naturally occurring stable Ca isotope variations in urine are emerging as a powerful tool to detect changes in bone mineral balance. Bone formation depletes soft tissue of light Ca isotopes while bone resorption releases isotopically light Ca into soft tissue. Previously published work found that variations in Ca isotope composition could be detected at 4 weeks of bed rest in a 90-day bed rest study (data collected at 4, 8 and 12 weeks). A new 30-day bed rest study involved 12 patients on a controlled diet, monitored for 7 days prior to bed rest and 7 days post bed rest. Samples of urine, blood and food were collected throughout the study. Four times daily blood samples and per void urine samples were collected to monitor diurnal or high frequency variations. An improved chemical purification protocol, followed by measurement using multiple collector inductively coupled plasma mass spectrometry (MC-ICP-MS) allowed accurate and precise determinations of mass-dependent Ca isotope variations in these biological samples to better than ±0.2% (δ44/42Ca) on <25 μg of Ca. Results from this new study show that Ca isotope ratios shift in a direction consistent with net bone loss after just 7 days, long before detectible changes in bone density by X-ray measurements occur. Consistent with this interpretation, the Ca isotope variations track changes observed in N-teleopeptide, a bone resorption biomarker. Bone-specific alkaline phosphatase, a bone formation biomarker, is unchanged over this period. Ca isotopes can in principle be used to quantify net changes in bone mass. Using a mass-balance model, our results indicate an average loss of 0.62 ± 0.16 % in bone mass over the course of this 30-day study. This is consistent with the rate of bone loss in longer-term studies as seen by X-ray measurements. This Ca isotope technique should accelerate the pace of discovery of new treatments for bone disease and provide novel insights into the dynamics of bone metabolism.

Neutron-Induced Fission Cross Section Measurements for Full Suite of Uranium Isotopes

NASA Astrophysics Data System (ADS)

Laptev, Alexander; Tovesson, Fredrik; Hill, Tony

2010-11-01

A well established program of neutron-induced fission cross section measurement at Los Alamos Neutron Science Center (LANSCE) is supporting the Fuel Cycle Research program (FC R&D). The incident neutron energy range spans energies from sub-thermal energies up to 200 MeV by measuring both the Lujan Center and the Weapons Neutron Research center (WNR). Conventional parallel-plate fission ionization chambers with actinide deposited foils are used as a fission detector. The time-of-flight method is implemented to measure neutron energy. Counting rate ratio from investigated and standard U-235 foils is translated into fission cross section ratio. Different methods of normalization for measured ratio are employed, namely, using of actinide deposit thicknesses, normalization to evaluated data, etc. Finally, ratios are converted to cross sections based on the standard U-235 fission cross section data file. Preliminary data for newly investigated isotopes U-236 and U-234 will be reported. Those new data complete a full suite of Uranium isotopes, which were investigated with presented experimental approach. When analysis of the new measured data will is completed, data will be delivered to evaluators. Having data for full set of Uranium isotopes will increase theoretical modeling capabilities and make new data evaluations much more reliable.

Maximal isometric muscle strength values obtained By hand-held dynamometry in children between 6 and 15 years of age.

PubMed

Escobar, Raul G; Munoz, Karin T; Dominguez, Angelica; Banados, Pamela; Bravo, Maria J

2017-01-01

In this study we aimed to determine the maximal isometric muscle strength of a healthy, normal-weight, pediatric population between 6 and 15 years of age using hand-held dynamometry to establish strength reference values. The secondary objective was determining the relationship between strength and anthropometric parameters. Four hundred normal-weight Chilean children, split into 10 age groups, separated by 1-year intervals, were evaluated. Each age group included between 35 and 55 children. The strength values increased with increasing age and weight, with a correlation of 0.83 for age and 0.82 for weight. The results were similar to those reported in previous studies regarding the relationships among strength, age, and anthropometric parameters, but the reported strength differed. These results provide normal strength parameters for healthy and normal-weight Chilean children between 6 and 15 years of age and highlight the relevance of ethnicity in defining reference values for muscle strength in a pediatric population. Muscle Nerve 55: 16-22, 2017. © 2016 Wiley Periodicals, Inc.

Advances in Methane Isotope Measurements via Direct Absorption Spectroscopy with Applications to Oil and Gas Source Characterization

NASA Astrophysics Data System (ADS)

Yacovitch, T. I.; Herndon, S. C.; Roscioli, J. R.; Petron, G.; Shorter, J. H.; Jervis, D.; McManus, J. B.; Nelson, D. D.; Zahniser, M. S.; Kolb, C. E., Jr.

2015-12-01

Instrumental developments in the measurement of multiple isotopes of methane (12CH4, 13CH4 and 12CH3D) are presented. A first generation 8-micron instrument quantifies 12CH4 and 13CH4 at a 1-second rate via tunable infrared direct absorption spectroscopy (TILDAS). A second generation instrument uses two 3-micron intraband cascade lasers in an Aerodyne dual laser chassis for simultaneous measurement of 12CH4, 13CH4 and 12CH3D. Sensitivity and noise performance improvements are examined. The isotopic signature of methane provides valuable information for emission source identification of this greenhouse gas. A first generation spectrometer has been deployed in the field on a mobile laboratory along with a sophisticated 4-tank calibration system. Calibrations are done on an agressive schedule, allowing for the correction of measured isotope ratios to an absolute isotope scale. Distinct isotopic signatures are found for a number of emission sources in the Denver-Julesburg Basin: oil and gas gathering stations, compressor stations and processing plants; a municipal landfill, and dairy/cattle operations. The isotopic signatures are compared with measured ethane/methane ratios. These direct absorption measurements have larger uncertainties than samples measured via gas chromatography-mass spectrometry, but have several advantages over canister sampling methods: individual sources of short duration are easier to isolate; calibrated isotope ratio results are available immediately; replicate measurements on a single source are easily performed; and the number of sources sampled is not limited by canister availability and processing time.

Isotopic Ratios Measured in the Dust of Comet 67P/Churyumov-Gerasimenko Using Rosetta/COSIMA

NASA Astrophysics Data System (ADS)

Paquette, J. A.; Engrand, C.; Hilchenbach, M.; Fray, N.; Stenzel, O.; Merouane, S.

2017-12-01

The COSIMA instrument aboard the Rosetta orbiter captured dust from the coma of comet 67P/Churyumov-Gerasimenko on metal targets. The dust was then imaged, and some of it was subjected to Time of Flight Secondary Ion Mass Spectrometry, yielding information on the dust composition. Isotopic ratios for species such as oxygen and sulfur have been measured for a number of COSIMA dust particles and these measurements are presented in this talk. Isotopic ratios for several species have been measured for a number of comets, but with the exception of the Stardust results, these have been measurements in the gas phase. The measurements presented here are from the solid phase, most probably from silicate or carbonaceous material. The isotopic ratios measured in the dust are compared to the measurements in the gas, to values measured in the insoluble organic matter of meteorites, and to the values measured in interplanetary dust particles and Antarctic micrometeorites.

Partitioning evapotranspiration fluxes with water stable isotopic measurements: from the lab to the field

NASA Astrophysics Data System (ADS)

Quade, M. E.; Brueggemann, N.; Graf, A.; Rothfuss, Y.

2017-12-01

Water stable isotopes are powerful tools for partitioning net into raw water fluxes such as evapotranspiration (ET) into soil evaporation (E) and plant transpiration (T). The isotopic methodology for ET partitioning is based on the fact that E and T have distinct water stable isotopic compositions, which in turn relies on the fact that each flux is differently affected by isotopic kinetic effects. An important work to be performed in parallel to field measurements is to better characterize these kinetic effects in the laboratory under controlled conditions. A soil evaporation laboratory experiment was conducted to retrieve characteristic values of the kinetic fractionation factor (αK) under varying soil and atmospheric water conditions. For this we used a combined soil and atmosphere column to monitor the soil and atmospheric water isotopic composition profiles at a high temporal and vertical resolution in a nondestructive manner by combining micro-porous membranes and laser spectroscopy. αK was calculated by using a well-known isotopic evaporation model in an inverse mode with the isotopic composition of E as one input variable, which was determined using a micro-Keeling regression plot. Knowledge on αK was further used in the field (Selhausen, North Rhine-Westphalia, Germany) to partition ET of catch crops and sugar beet (Beta vulgaris) during one growing season. Soil and atmospheric water isotopic profiles were measured automatically across depths and heights following a similar modus operandi as in the laboratory experiment. Additionally, a newly developed continuously moving elevator was used to obtain water vapor isotopic composition profiles with a high vertical resolution between soil surface, plant canopy and atmosphere. Finally, soil and plant samples were collected destructively to provide a comparison with the traditional isotopic methods. Our results illustrate the changing proportions of T and E along the growing season and demonstrate the

Steps toward identifying a biogeochemical signal in non-equilibrium methane clumped isotope measurements

NASA Astrophysics Data System (ADS)

Douglas, P. M.; Eiler, J. M.; Sessions, A. L.; Dawson, K.; Walter Anthony, K. M.; Smith, D. A.; Lloyd, M. K.; Yanay, E.

2016-12-01

Microbially produced methane is a globally important greenhouse gas, energy source, and biological substrate. Methane clumped isotope measurements have recently been developed as a new analytical tool for understanding the source of methane in different environments. When methane forms in isotopic equilibrium clumped isotope values are determined by formation temperature, but in many cases microbial methane clumped isotope values deviate strongly from expected equilibrium values. Indeed, we observe a very wide range of clumped isotope values in microbial methane, which are likely strongly influenced by kinetic isotope effects, but thus far the biological and environmental parameters controlling this variability are not understood. We will present data from both culture experiments and natural environments to explore patterns of variability in non-equilibrium clumped isotope values on temporal and spatial scales. In methanogen batch cultures sampled at different time points along a growth curve we observe significant variability in clumped isotope values, with values decreasing from early to late exponential growth. Clumped isotope values then increase during stationary growth. This result is consistent with previous work suggesting that differences in the reversibility of methanogenesis related to metabolic rates control non-equilibrium clumped isotope values. Within single lakes in Alaska and Sweden we observe substantial variability in clumped isotope values on the order of 5‰. Lower clumped isotope values are associated with larger 2H isotopic fractionation between water and methane, which is also consistent with a kinetic isotope effect determined by the reversibility of methanogenesis. Finally, we analyzed a time-series clumped isotope compositions of methane emitted from two seeps in an Alaskan lake over several months. Temporal variability in these seeps is on the order of 2‰, which is much less than the observed spatial variability within the lake

Application of neodymium isotope ratio measurements for the origin assessment of uranium ore concentrates.

PubMed

Krajkó, Judit; Varga, Zsolt; Yalcintas, Ezgi; Wallenius, Maria; Mayer, Klaus

2014-11-01

A novel procedure has been developed for the measurement of (143)Nd/(144)Nd isotope ratio in various uranium-bearing materials, such as uranium ores and ore concentrates (UOC) in order to evaluate the usefulness and applicability of variations of (143)Nd/(144)Nd isotope ratio for provenance assessment in nuclear forensics. Neodymium was separated and pre-concentrated by extraction chromatography and then the isotope ratios were measured by multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS). The method was validated by the measurement of standard reference materials (La Jolla, JB-2 and BCR-2) and the applicability of the procedure was demonstrated by the analysis of uranium samples of world-wide origin. The investigated samples show distinct (143)Nd/(144)Nd ratio depending on the ore type, deposit age and Sm/Nd ratio. Together with other characteristics of the material in question, the Nd isotope ratio is a promising signature for nuclear forensics and suggests being indicative of the source material, the uranium ore. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

Study of Hand-Held Fire Extinguishers Aboard Civil Aviation Aircraft.

DTIC Science & Technology

1982-06-01

or combustion products of the polymers used in aircraft construction have been found to include carbon monoxide (CO), carbon dioxide (CO ), hydrogen...toxicity rating, and ease of cleanup. The extinguishing agents used in this country for hand portable fire extinguishers are Carbon Dioxide, water, Halon...point where combustion stops." " Carbon dioxide fire extinguishing systems are useful within the limits of this standard in extinguishing fires in

Constraints on nitrogen cycling at the subtropical North Pacific Station ALOHA from isotopic measurements of nitrate and particulate nitrogen

NASA Astrophysics Data System (ADS)

Casciotti, K. L.; Trull, T. W.; Glover, D. M.; Davies, D.

2008-07-01

Nitrogen supply to surface waters can play an important role in the productivity and ecology of subtropical ecosystems. As part of the Vertical Transport in the Global Ocean (VERTIGO) program, we examined the fluxes of nitrogen into and out of the euphotic zone at station ALOHA in the North Pacific Subtropical Gyre using natural abundance stable isotopic measurements of nitrate ( δN and δO), as well as sinking and suspended particulate nitrogen (δ 15N PN). Paralleling the steep gradient in nitrate concentration in the upper thermocline at ALOHA, we observed a steep gradient in δN, decreasing from a maximum of +7.1‰ at 500 meters (m) to +1.5-2.4‰ at 150 m. δO values also decreased from +3.0‰ at 300 m to +0.7-0.9‰ at 150 m. The decreases in both δN and δO require inputs of isotopically "light" nitrate to balance the upward flux of nitrate with high δN (and δO). We conclude that both nitrogen fixation and diagenetic alteration of the sinking flux contribute to the decrease in δN and δO in the upper thermocline at station ALOHA. While nitrogen fixation is required to explain the nitrogen isotope patterns, the rates of nitrogen fixation may be lower than previously estimated. By including high-resolution nitrate isotope measurements in the nitrogen isotope budget for the euphotic zone at ALOHA, we estimate that approximately 25%, rather than 50%, of export production was fueled by N 2 fixation during our study. On the other hand, this input of N 2-derived production accumulates in the upper thermocline over time, playing a significant role in subtropical nutrient cycling through maintenance of the subsurface nitrate pool. An increase in sinking δ 15N PN between 150 and 300 m, also suggests that fractionation during remineralization contributed to the low δN values observed in this depth range by introducing a subsurface nitrate source that is 0.5‰ lower in δ 15N than the particle flux exported from the euphotic zone. While the time scale of these

TEMTADS Adjunct Sensor Systems Hand-Held EMI Sensor for Cued UXO Discrimination (ESTCP MR-200807) and Man-Portable EMI Array for UXO Detection and Discrimination (ESTCP MR-200909)

DTIC Science & Technology

2012-04-05

C la ss ifi ca tio n TY PE D ep th (M ) A zi m ut h (D eg re es ) D ip (D eg re es ) 1 2 3...Naval Research Laboratory Washington, DC 20375-5320 NRL/MR/ 6110 --12-9401 TEMTADS Adjunct Sensor Systems Hand-held EMI Sensor for Cued UXO...NUMBER 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 5d. PROJECT NUMBER 5e. TASK NUMBER 5f. WORK UNIT NUMBER 2 . REPORT TYPE1. REPORT DATE (DD-MM-YYYY) 4

29 CFR 1910.242 - Hand and portable powered tools and equipment, general.

Code of Federal Regulations, 2011 CFR

2011-07-01

... to less than 30 p.s.i. and then only with effective chip guarding and personal protective equipment. ... 29 Labor 5 2011-07-01 2011-07-01 false Hand and portable powered tools and equipment, general... Powered Tools and Other Hand-Held Equipment § 1910.242 Hand and portable powered tools and equipment...

29 CFR 1910.242 - Hand and portable powered tools and equipment, general.

Code of Federal Regulations, 2010 CFR

2010-07-01

... to less than 30 p.s.i. and then only with effective chip guarding and personal protective equipment. ... 29 Labor 5 2010-07-01 2010-07-01 false Hand and portable powered tools and equipment, general... Powered Tools and Other Hand-Held Equipment § 1910.242 Hand and portable powered tools and equipment...

Detection of counterfeit antiviral drug Heptodin and classification of counterfeits using isotope amount ratio measurements by multicollector inductively coupled plasma mass spectrometry (MC-ICPMS) and isotope ratio mass spectrometry (IRMS).

PubMed

Santamaria-Fernandez, Rebeca; Hearn, Ruth; Wolff, Jean-Claude

2009-06-01

Isotope ratio mass spectrometry (IRMS) and multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS) are highly important techniques that can provide forensic evidence that otherwise would not be available. MC-ICP-MS has proved to be a very powerful tool for measuring high precision and accuracy isotope amount ratios. In this work, the potential of combining isotope amount ratio measurements performed by MC-ICP-MS and IRMS for the detection of counterfeit pharmaceutical tablets has been investigated. An extensive study for the antiviral drug Heptodin has been performed for several isotopic ratios combining MC-ICP-MS and an elemental analyser EA-IRMS for stable isotope amount ratio measurements. The study has been carried out for 139 batches of the antiviral drug and analyses have been performed for C, S, N and Mg isotope ratios. Authenticity ranges have been obtained for each isotopic system and combined to generate a unique multi-isotopic pattern only present in the genuine tablets. Counterfeit tablets have then been identified as those tablets with an isotopic fingerprint outside the genuine isotopic range. The combination of those two techniques has therefore great potential for pharmaceutical counterfeit detection. A much greater power of discrimination is obtained when at least three isotopic systems are combined. The data from these studies could be presented as evidence in court and therefore methods need to be validated to support their credibility. It is also crucial to be able to produce uncertainty values associated to the isotope amount ratio measurements so that significant differences can be identified and the genuineness of a sample can be assessed.

Exhaled nitric oxide measurements: correction equation to compare hand-held device to stationary analyzer.

PubMed

Pizzimenti, Stefano; Bugiani, Massimiliano; Piccioni, Pavilio; Heffler, Enrico; Carosso, Aurelia; Guida, Giuseppe; Rolla, Giovanni

2008-09-01

Exhaled nitric oxide (FE(NO)) is a reliable non-invasive marker of airway inflammation. In 2003 FE(NO) chemiluminescence analyzer (NIOX; Aerocrine AB, Solna, Sweden) was approved by U.S. Food and Drug Administration for monitoring asthma therapy. Recently, the same company developed a portable device using electrochemical sensors (NIOX-MINO; Aerocrine AB). The aim of our study was to compare NIOX-MINO FE(NO) values to those obtained by NIOX and to calculate a correction equation. Two adequate measurements obtained by NIOX and NIOX-MINO were recorded in 32 subjects (16 females, mean age 41 years). FE(NO) values measured by NIOX-MINO were systematically higher than those obtained by NIOX (47.1ppb, IC 95% 35.2-59.1 and 36.9ppb, IC 95% 25.0-49.0, respectively). There was a significant correlation (r=0.998, p<0.001) between FE(NO) measured by the two analyzers and the following conversion equation was calculated as: FE(NO(NIOX))=-1.656(SE=0.61)+0.808(SE=0.009)x FE(NO(NIOX-MINO)) DISCUSSION: FE(NO) values measured by the portable nitric oxide analyzer are reliable and strongly correlated with values obtained by the standard stationary device, with a systematic difference observed between the two instruments' values that can be described by the conversion equation we provided. This equation will help clinicians and researchers to compare data obtainable by the two analyzers.

Reliability of infrared thermometric measurements of skin temperature in the hand.

PubMed

Packham, Tara L; Fok, Diana; Frederiksen, Karen; Thabane, Lehana; Buckley, Norman

2012-01-01

Clinical measurement study. Skin temperature asymmetries (STAs) are used in the diagnosis of complex regional pain syndrome (CRPS), but little evidence exists for reliability of the equipment and methods. This study examined the reliability of an inexpensive infrared (IR) thermometer and measurement points in the hand for the study of STA. ST was measured three times at five points on both hands with an IR thermometer by two raters in 20 volunteers (12 normals and 8 CRPS). ST measurement results using IR thermometers support inter-rater reliability: intraclass correlation coefficient (ICC) estimate for single measures 0.80; all ST measurement points were also highly reliable (ICC single measures, 0.83-0.91). The equipment demonstrated excellent reliability, with little difference in the reliability of the five measurement sites. These preliminary findings support their use in future CRPS research. Not applicable. Copyright © 2012 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

RAPID3 scores and hand outcome measurements in RA patients: a preliminary study.

PubMed

Qorolli, Merita; Hundozi-Hysenaj, Hajrije; Rexhepi, Sylejman; Rehxepi, Blerta; Grazio, Simeon

2017-06-01

The Routine Assessment of Patient Index Data 3 (RAPID3) is a patient-reported disease activity measure used to assess physical function, pain, and global health in patients with rheumatoid arthritis (RA) without formal joint counts. Since hand involvement and its decreased function are hallmarks of RA, the aim of our study was to investigate the performance of RAPID3 scores with regard to hand function and to confirm previous findings that the RAPID3 score as a disease activity measure is strongly correlated with the DAS28 score. Sixty-eight consecutive patients with RA (85% female), aged 18-75 years, were included in the study and were recruited during their outpatient visit. Apart from demographic and clinical data, the obtained parameters of interest included RAPID3 scores and assessments of the function of the hand, namely, the signal of functional impairment (SOFI)-hand, grip strength, and pulp-to-palm distance, as well the Health Assessment Questionnaire- Disability Index (HAQ-DI) and DAS28 scores. Pearson's correlation coefficient, Student's t test and linear regression were used in the statistical analysis of the results. The significance was set to p < 0.05. A positive correlation was found between RAPID3 scores and HAQ-DI scores, SOFI-hand scores, and pulp-to-palm distance, and negative correlation was observed between RAPID3 scores and grip strength. The order regarding the strength of correlations between RAPID3 scores and other variables (from the strongest to the weakest) was as follows: HAQ-DI, grip strength, SOFI-hand and pulp-to-palm distance. The hand assessment variables had stronger correlations with RAPID3 scores than with DAS28 scores. Our preliminary study showed that RAPID3 scores were strongly correlated with measurements of the functional ability of the hand, demonstrating that RAPID3 can be used as a measure of disease activity in clinical practice and to characterize hand function. Further studies are needed to confirm this result.

Analysis of shipboard aerosol optical thickness measurements from multiple sunphotometers aboard the R/V Ronald H. Brown during the Aerosol Characterization Experiment - Asia

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miller, Mark A.; Knobelspiesse, Kirk; Frouin, Robert

2005-06-20

Marine sunphotometer measurements collected aboard the R/V Ronald H. Brown during the Aerosol Characterization Experiment - Asia (ACE-Asia) are used to evaluate the ability of complementary instrumentation to obtain the best possible estimates of aerosol optical thickness and Angstrom exponent from ships at sea. A wide range of aerosol conditions, including clean maritime conditions and highly polluted coastal environments, were encountered during the ACE-Asia cruise. The results of this study suggest that shipboard hand-held sunphotometers and fast-rotating shadow-band radiometers (FRSRs) yield similar measurements and uncertainties if proper measurement protocols are used and if the instruments are properly calibrated. The automatedmore » FRSR has significantly better temporal resolution (2 min) than the hand-held sunphotometers when standard measurement protocols are used, so it more faithfully represents the variability of the local aerosol structure in polluted regions. Conversely, results suggest that the hand-held sunphotometers may perform better in clean, maritime air masses for unknown reasons. Results also show that the statistical distribution of the Angstrom exponent measurements is different when the distributions from hand-held sunphotometers are compared with those from the FRSR and that the differences may arise from a combination of factors.« less

Development of an observational measure of healthcare worker hand-hygiene behaviour: the hand-hygiene observation tool (HHOT).

PubMed

McAteer, J; Stone, S; Fuller, C; Charlett, A; Cookson, B; Slade, R; Michie, S

2008-03-01

Previous observational measures of healthcare worker (HCW) hand-hygiene behaviour (HHB) fail to provide adequate standard operating procedures (SOPs), accounts of inter-rater agreement testing or evidence of sensitivity to change. This study reports the development of an observational tool in a way that addresses these deficiencies. Observational categories were developed systematically, guided by a clinical guideline, previous measures and pilot hand-hygiene behaviour observations (HHOs). The measure, a simpler version of the Geneva tool, consists of HHOs (before and after low-risk, high-risk or unobserved contact), HHBs (soap, alcohol hand rub, no action, unknown), and type of HCW. Inter-observer agreement for each category was assessed by observation of 298 HHOs and HHBs by two independent observers on acute elderly and intensive care units. Raw agreement (%) and Kappa were 77% and 0.68 for HHB; 83% and 0.77 for HHO; and 90% and 0.77 for HCW. Inter-observer agreement for overall compliance of a group of HCWs was assessed by observation of 1191 HHOs and HHBs by two pairs of independent observers. Overall agreement was good (intraclass correlation coefficient = 0.79). Sensitivity to change was examined by autoregressive time-series modelling of longitudinal observations for 8 months on the intensive therapy unit during an Acinetobacter baumannii outbreak and subsequent strengthening of infection control measures. Sensitivity to change was demonstrated by a rise in compliance from 80 to 98% with an odds ratio of increased compliance of 7.00 (95% confidence interval: 4.02-12.2) P < 0.001.

Water isotope systematics: Improving our palaeoclimate interpretations

USGS Publications Warehouse

Jones, M. D.; Dee, S.; Anderson, L.; Baker, A.; Bowen, G.; Noone, D.

2016-01-01

The stable isotopes of oxygen and hydrogen, measured in a variety of archives, are widely used proxies in Quaternary Science. Understanding the processes that control δ18O change have long been a focus of research (e.g. Shackleton and Opdyke, 1973; Talbot, 1990 ; Leng, 2006). Both the dynamics of water isotope cycling and the appropriate interpretation of geological water-isotope proxy time series remain subjects of active research and debate. It is clear that achieving a complete understanding of the isotope systematics for any given archive type, and ideally each individual archive, is vital if these palaeo-data are to be used to their full potential, including comparison with climate model experiments of the past. Combining information from modern monitoring and process studies, climate models, and proxy data is crucial for improving our statistical constraints on reconstructions of past climate variability.As climate models increasingly incorporate stable water isotope physics, this common language should aid quantitative comparisons between proxy data and climate model output. Water-isotope palaeoclimate data provide crucial metrics for validating GCMs, whereas GCMs provide a tool for exploring the climate variability dominating signals in the proxy data. Several of the studies in this set of papers highlight how collaborations between palaeoclimate experimentalists and modelers may serve to expand the usefulness of palaeoclimate data for climate prediction in future work.This collection of papers follows the session on Water Isotope Systematics held at the 2013 AGU Fall Meeting in San Francisco. Papers in that session, the breadth of which are represented here, discussed such issues as; understanding sub-GNIP scale (Global Network for Isotopes in Precipitation, (IAEA/WMO, 2006)) variability in isotopes in precipitation from different regions, detailed examination of the transfer of isotope signals from precipitation to geological archives, and the

Evaluation strategies for isotope ratio measurements of single particles by LA-MC-ICPMS.

PubMed

Kappel, S; Boulyga, S F; Dorta, L; Günther, D; Hattendorf, B; Koffler, D; Laaha, G; Leisch, F; Prohaska, T

2013-03-01

Data evaluation is a crucial step when it comes to the determination of accurate and precise isotope ratios computed from transient signals measured by multi-collector-inductively coupled plasma mass spectrometry (MC-ICPMS) coupled to, for example, laser ablation (LA). In the present study, the applicability of different data evaluation strategies (i.e. 'point-by-point', 'integration' and 'linear regression slope' method) for the computation of (235)U/(238)U isotope ratios measured in single particles by LA-MC-ICPMS was investigated. The analyzed uranium oxide particles (i.e. 9073-01-B, CRM U010 and NUSIMEP-7 test samples), having sizes down to the sub-micrometre range, are certified with respect to their (235)U/(238)U isotopic signature, which enabled evaluation of the applied strategies with respect to precision and accuracy. The different strategies were also compared with respect to their expanded uncertainties. Even though the 'point-by-point' method proved to be superior, the other methods are advantageous, as they take weighted signal intensities into account. For the first time, the use of a 'finite mixture model' is presented for the determination of an unknown number of different U isotopic compositions of single particles present on the same planchet. The model uses an algorithm that determines the number of isotopic signatures by attributing individual data points to computed clusters. The (235)U/(238)U isotope ratios are then determined by means of the slopes of linear regressions estimated for each cluster. The model was successfully applied for the accurate determination of different (235)U/(238)U isotope ratios of particles deposited on the NUSIMEP-7 test samples.

Electron-capture Isotopes Could Constrain Cosmic-Ray Propagation Models

NASA Astrophysics Data System (ADS)

Benyamin, David; Shaviv, Nir J.; Piran, Tsvi

2017-12-01

Electron capture (EC) isotopes are known to provide constraints on the low-energy behavior of cosmic rays (CRs), such as reacceleration. Here, we study the EC isotopes within the framework of the dynamic spiral-arms CR propagation model in which most of the CR sources reside in the galactic spiral arms. The model was previously used to explain the B/C and sub-Fe/Fe ratios. We show that the known inconsistency between the 49Ti/49V and 51V/51Cr ratios remains also in the spiral-arms model. On the other hand, unlike the general wisdom that says the isotope ratios depend primarily on reacceleration, we find here that the ratio also depends on the halo size (Z h) and, in spiral-arms models, also on the time since the last spiral-arm passage ({τ }{arm}). Namely, EC isotopes can, in principle, provide interesting constraints on the diffusion geometry. However, with the present uncertainties in the lab measurements of both the electron attachment rate and the fragmentation cross sections, no meaningful constraint can be placed.

Guidelines and recommended terms for expression of stable-isotope-ratio and gas-ratio measurement results

USGS Publications Warehouse

Coplen, Tyler B.

2011-01-01

To minimize confusion in the expression of measurement results of stable isotope and gas-ratio measurements, recommendations based on publications of the Commission on Isotopic Abundances and Atomic Weights of the International Union of Pure and Applied Chemistry (IUPAC) are presented. Whenever feasible, entries are consistent with the Système International d'Unités, the SI (known in English as the International System of Units), and the third edition of the International Vocabulary of Basic and General Terms in Metrology (VIM, 3rd edition). The recommendations presented herein are approved by the Commission on Isotopic Abundances and Atomic Weights and are designed to clarify expression of quantities related to measurement of isotope and gas ratios to ensure that quantity equations instead of numerical value equations are used for quantity definitions. Examples of column headings consistent with quantity calculus (also called the algebra of quantities) and examples of various deprecated usages connected with the terms recommended are presented.

Ground based mobile isotopic methane measurements in the Front Range, Colorado

NASA Astrophysics Data System (ADS)

Vaughn, B. H.; Rella, C.; Petron, G.; Sherwood, O.; Mielke-Maday, I.; Schwietzke, S.

2014-12-01

Increased development of unconventional oil and gas resources in North America has given rise to attempts to monitor and quantify fugitive emissions of methane from the industry. Emission estimates of methane from oil and gas basins can vary significantly from one study to another as well as from EPA or State estimates. New efforts are aimed at reconciling bottom-up, or inventory-based, emission estimates of methane with top-down estimates based on atmospheric measurements from aircraft, towers, mobile ground-based vehicles, and atmospheric models. Attributing airborne measurements of regional methane fluxes to specific sources is informed by ground-based measurements of methane. Stable isotopic measurements (δ13C) of methane help distinguish between emissions from the O&G industry, Confined Animal Feed Operations (CAFO), and landfills, but analytical challenges typically limit meaningful isotopic measurements to individual point sampling. We are developing a toolbox to use δ13CH4 measurements to assess the partitioning of methane emissions for regions with multiple methane sources. The method was applied to the Denver-Julesberg Basin. Here we present data from continuous isotopic measurements obtained over a wide geographic area by using MegaCore, a 1500 ft. tube that is constantly filled with sample air while driving, then subsequently analyzed at slower rates using cavity ring down spectroscopy (CRDS). Pressure, flow and calibration are tightly controlled allowing precise attribution of methane enhancements to their point of collection. Comparisons with point measurements are needed to confirm regional values and further constrain flux estimates and models. This effort was made in conjunction with several major field campaigns in the Colorado Front Range in July-August 2014, including FRAPPÉ (Front Range Air Pollution and Photochemistry Experiment), DISCOVER-AQ, and the Air Water Gas NSF Sustainability Research Network at the University of Colorado.

Paleoproxies: Heavy Stable Isotope Perspectives

NASA Astrophysics Data System (ADS)

Nagler, T. F.; Hippler, D.; Siebert, C.; Kramers, J. D.

2002-12-01

Recent advances in isotope ratio mass spectrometry, namely multiple collector ICP-MS and refined TIMS techniques, will significantly enhance the ability to measure heavy stable isotope fractionation, which will lead to the development of a wide array of process-identifying (bio)-geochemical tools. Thus far research in this area is not easily assessable to scientists outside the isotope field. This is due to the fact that analyzing heavy stable isotopes does not provide routine numbers which are per se true (the preciser the truer) but is still a highly experimental field. On the other hand resolving earth science problems requires specialists familiar with the environment being studied. So what is in there for paleoceanographers? In a first order approach, relating isotope variations to physical processes is straightforward. A prominent example are oxygen isotope variations with temperature. The total geological signal is of course far more complicated. At low temperatures, heavy stable isotopes variations have been reported for e.g. Ca, Cr, Fe, Cu, Zn, Mo and Tl. Fractionation mechanisms and physical parameters responsible for the observed variations are not yet resolved for most elements. Significant equilibrium isotope fractionation is expected from redox reactions of transition metals. However a difference in coordination number between two coexisting speciations of an element in the same oxidation state can also cause fractionation. Protonation of dissolved Mo is one case currently discussed. For paleoceanography studies, a principal distinction between transition metals essential for life (V to Zn plus Mo) or not will be helpful. In case of the former group, distinction between biogenic and abiogenic isotope fractionation will remain an important issue. For example, abiotic Fe redox reactions result in isotope fractionations indistinguishable in direction and magnitude from microbial effects. Only a combination of different stable isotope systems bears the

A precise few-nucleon size difference by isotope shift measurements of helium

NASA Astrophysics Data System (ADS)

Rezaeian, Nima Hassan

We perform high precision measurements of an isotope shift between the two stable isotopes of helium. We use laser excitation of the 23 S1 -- 23P0 transition at 1083 .... in a metastable beam of 3He and 4He atoms. A newly developed tunable laser frequency selector along with our previous electro-optic frequency modulation technique provides extremely reliable, adaptable, and precise frequency and intensity control. The intensity control contributes negligibly to overall experimental uncertainty by selecting (t selection < 50 ) and stabilizing the intensity of the required sideband and eliminating (˜10-5) the unwanted frequencies generated during the modulation of 1083 nm laser carrier frequency. The selection technique uses a MEMS based fiber switch (tswitch ≈ 10 ms) and several temperature stabilized narrow band (˜3 GHz) fiber gratings. A fiber based optical circulator and an inline fiber amplifier provide the desired isolation and the net gain for the selected frequency. Also rapid (˜2 sec.) alternating measurements of the 23 S1 -- 23P0 interval for both species of helium is achieved with a custom fiber laser for simultaneous optical pumping. A servo-controlled retro-reflected laser beam eliminates residual Doppler effects during the isotope shift measurement. An improved detection design and software control makes negligible subtle potential biases in the data collection. With these advances, combined with new internal and external consistency checks, we are able to obtain results consistent with the best previous measurements, but with substantially improved precision. Our measurement of the 23S 1 -- 23P0 isotope shift between 3He and 4He is 31 097 535.2 (5)kHz. The most recent theoretic calculation combined with this measuremen. yields a new determination for nuclear size differences between 3He and 4He: Deltarc = 0.292 6 (1)exp (8)th(52)expfm, with a precision of less than a part in 104 coming from the experimental uncertainty (first parenthesis), and a

Measurement of (n,α) cross section for set of structural material isotopes

NASA Astrophysics Data System (ADS)

Khryachkov, Vitaly; Gurbich, Alexander; Khromyleva, Tatiana; Bondarenko, Ivan; Ketlerov, Vladimir; Prusachenko, Pavel

2017-09-01

A novel spectrometer was developed and used to measure the cross section for the (n,α) reaction at IPPE. Direct measurements of the α-particles yield from solid isotopic pure targets of 50, 52 and 53 chromium, 54 and 57 iron, 60 nickel, and 64 zinc were carried out in the neutron energy range from 4.7 to 7.2 MeV. For some isotopes the (n,α) reaction cross-section for neutron energies less than 14 MeV were measured for the first time. The result of the comparison of new experimental data with the evaluated data from libraries ENDF/B VII, JENDL 4.0, JEFF 3.1, ROSFOND 2010 and BROND 3 and with the experimental data of other authors is presented.

Measurement properties of the Patient-Rated Wrist and Hand Evaluation: Rasch analysis of responses from a traumatic hand injury population.

PubMed

Packham, Tara; MacDermid, Joy C

2013-01-01

The Patient-Rated Wrist and Hand Evaluation (PRWHE) is a self-reported assessment of pain and disability to evaluate outcome after hand injuries. Rasch analysis is an alternative strategy for examining the psychometric properties of a measurement scale based in item response theory, rather than classical test theory. This study used Rasch analysis to examine the content, scoring and measurement properties of the PRWHE. PRWHE scores (n = 264) from persons with a traumatic injury or reconstructive surgery to one hand were collected from an outpatient hand rehabilitation facility. Rasch analysis was conducted to assess how the PRWHE fit the Rasch model, confirms the scaling structure of the pain and disability subscales, and identifies any areas of bias from differential item functioning. Rasch analysis of the PRWHE supports internal consistency of the scale (α = 0.96) and reliability (as measured by the person separation index) of 0.95. While gender, age, diagnosis, and duration since injury all systematically influenced how people scored the PRWHE, hand dominance and affected side did not. Rasch analysis supported a 3 subscale structure (pain, specific activities and usual activities) rather than the current divisions of pain and disability. Initial examination of the PRWHE indicates the psychometric properties of consistency, reliability and responsiveness previously tested by classical methods are further supported by Rasch analysis. It also suggests the scale structure may be best considered as 3 subscales rather than simply pain and disability. Copyright © 2013 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Beyond textbook illustrations: Hand-held models of ordered DNA and protein structures as 3D supplements to enhance student learning of helical biopolymers.

PubMed

Jittivadhna, Karnyupha; Ruenwongsa, Pintip; Panijpan, Bhinyo

2010-11-01

Textbook illustrations of 3D biopolymers on printed paper, regardless of how detailed and colorful, suffer from its two-dimensionality. For beginners, computer screen display of skeletal models of biopolymers and their animation usually does not provide the at-a-glance 3D perception and details, which can be done by good hand-held models. Here, we report a study on how our students learned more from using our ordered DNA and protein models assembled from colored computer-printouts on transparency film sheets that have useful structural details. Our models (reported in BAMBED 2009), having certain distinguished features, helped our students to grasp various aspects of these biopolymers that they usually find difficult. Quantitative and qualitative learning data from this study are reported. Copyright © 2010 International Union of Biochemistry and Molecular Biology, Inc.

Toward a simple, repeatable, non-destructive approach to measuring stable-isotope ratios of water within tree stems

NASA Astrophysics Data System (ADS)

Raulerson, S.; Volkmann, T.; Pangle, L. A.

2017-12-01

Traditional methodologies for measuring ratios of stable isotopes within the xylem water of trees involve destructive coring of the stem. A recent approach involves permanently installed probes within the stem, and an on-site assembly of pumps, switching valves, gas lines, and climate-controlled structure for field deployment of a laser spectrometer. The former method limits the possible temporal resolution of sampling, and sample size, while the latter may not be feasible for many research groups. We present results from initial laboratory efforts towards developing a non-destructive, temporally-resolved technique for measuring stable isotope ratios within the xylem flow of trees. Researchers have used direct liquid-vapor equilibration as a method to measure isotope ratios of the water in soil pores. Typically, this is done by placing soil samples in a fixed container, and allowing the liquid water within the soil to come into isotopic equilibrium with the headspace of the container. Water can also be removed via cryogenic distillation or azeotropic distillation, with the resulting liquid tested for isotope ratios. Alternatively, the isotope ratios of the water vapor can be directly measured using a laser-based water vapor isotope analyzer. Well-established fractionation factors and the isotope ratios in the vapor phase are then used to calculate the isotope ratios in the liquid phase. We propose a setup which would install a single, removable chamber onto a tree, where vapor samples could non-destructively and repeatedly be taken. These vapor samples will be injected into a laser-based isotope analyzer by a recirculating gas conveyance system. A major part of what is presented here is in the procedure of taking vapor samples at 100% relative humidity, appropriately diluting them with completely dry N2 calibration gas, and injecting them into the gas conveyance system without inducing fractionation in the process. This methodology will be helpful in making

Measurement of sulfur isotope compositions by tunable laser spectroscopy of SO2.

PubMed

Christensen, Lance E; Brunner, Benjamin; Truong, Kasey N; Mielke, Randall E; Webster, Christopher R; Coleman, Max

2007-12-15

Sulfur isotope measurements offer comprehensive information on the origin and history of natural materials. Tunable laser spectroscopy is a powerful analytical technique for isotope analysis that has proven itself readily adaptable for in situ terrestrial and planetary measurements. Measurements of delta(34)S in SO2 were made using tunable laser spectroscopy of combusted gas samples from six sulfur-bearing solids with delta(34)S ranging from -34 to +22 per thousand (also measured with mass spectrometry). Standard deviation between laser and mass spectrometer measurements was 3.7 per thousand for sample sizes of 200 +/- 75 nmol SO(2). Although SO(2)(g) decreased 9% over 15 min upon entrainment in the analysis cell from wall uptake, observed fractionation was insignificant (+0.2 +/- 0.6 per thousand). We also describe a strong, distinct (33)SO(2) rovibrational transition in the same spectral region, which may enable simultaneous delta(34)S and Delta(33)S measurements.

A Non-Contact Measurement System for the Range of Motion of the Hand

PubMed Central

Pham, Trieu; Pathirana, Pubudu N.; Trinh, Hieu; Fay, Pearse

2015-01-01

An accurate and standardised tool to measure the active range of motion (ROM) of the hand is essential to any progressive assessment scenario in hand therapy practice. Goniometers are widely used in clinical settings for measuring the ROM of the hand. However, such measurements have limitations with regard to inter-rater and intra-rater reliability and involve direct physical contact with the hand, possibly increasing the risk of transmitting infections. The system proposed in this paper is the first non-contact measurement system utilising Intel Perceptual Technology and a Senz3D Camera for measuring phalangeal joint angles. To enhance the accuracy of the system, we developed a new approach to achieve the total active movement without measuring three joint angles individually. An equation between the actual spacial position and measurement value of the proximal inter-phalangeal joint was established through the measurement values of the total active movement, so that its actual position can be inferred. Verified by computer simulations, experimental results demonstrated a significant improvement in the calculation of the total active movement and successfully recovered the actual position of the proximal inter-phalangeal joint angles. A trial that was conducted to examine the clinical applicability of the system involving 40 healthy subjects confirmed the practicability and consistency in the proposed system. The time efficiency conveyed a stronger argument for this system to replace the current practice of using goniometers. PMID:26225976

Production of highly-enriched 134Ba for a reference material for isotope dilution mass spectrometry measurements

DOE PAGES

Horkley, J. J.; Carney, K. P.; Gantz, E. M.; ...

2015-03-17

Isotope dilution mass spectrometry (IDMS) is an analytical technique capable of providing accurate and precise quantitation of trace isotope abundance and assay providing measurement uncertainties below 1 %. To achieve these low uncertainties, the IDMS method ideally utilizes chemically pure “spike” solutions that consist of a single highly enriched isotope that is well-characterized relating to the abundance of companion isotopes and concentration in solution. To address a current demand for accurate 137Cs/137Ba ratio measurements for “age” determination of radioactive 137Cs sources, Idaho National Laboratory (INL) is producing enriched 134Ba isotopes that are tobe used for IDMS spikes to accurately determinemore » 137Ba accumulation from the decay of 137Cs. The final objective of this work it to provide a homogenous set of reference materials that the National Institute of Standards and Technology can certify as standard reference materials used for IDMS. The process that was developed at INL for the separation and isolation of Ba isotopes, chemical purification of the isotopes in solution, and the encapsulation of the materials will be described.« less

Towards the hand-held mass spectrometer: design considerations, simulation, and fabrication of micrometer-scaled cylindrical ion traps

NASA Astrophysics Data System (ADS)

Blain, Matthew G.; Riter, Leah S.; Cruz, Dolores; Austin, Daniel E.; Wu, Guangxiang; Plass, Wolfgang R.; Cooks, R. Graham

2004-08-01

Breakthrough improvements in simplicity and reductions in the size of mass spectrometers are needed for high-consequence fieldable applications, including error-free detection of chemical/biological warfare agents, medical diagnoses, and explosives and contraband discovery. These improvements are most likely to be realized with the reconceptualization of the mass spectrometer, rather than by incremental steps towards miniaturization. Microfabricated arrays of mass analyzers represent such a conceptual advance. A massively parallel array of micrometer-scaled mass analyzers on a chip has the potential to set the performance standard for hand-held sensors due to the inherit selectivity, sensitivity, and universal applicability of mass spectrometry as an analytical method. While the effort to develop a complete micro-MS system must include innovations in ultra-small-scale sample introduction, ion sources, mass analyzers, detectors, and vacuum and power subsystems, the first step towards radical miniaturization lies in the design, fabrication, and characterization of the mass analyzer itself. In this paper we discuss design considerations and results from simulations of ion trapping behavior for a micrometer scale cylindrical ion trap (CIT) mass analyzer (internal radius r0 = 1 [mu]m). We also present a description of the design and microfabrication of a 0.25 cm2 array of 106 one-micrometer CITs, including integrated ion detectors, constructed in tungsten on a silicon substrate.

Measurement Variation and the Factors Influencing the UV Index

ERIC Educational Resources Information Center

Downs, Nathan; Parisi, Alfio; McDonnell, Brendan; Thornton, Peter

2008-01-01

The article presents a technique to measure the ultraviolet index using a personal hand-held ultraviolet meter to illustrate concepts of physics. Measurements of the erythemally effective (sun-burning) direct solar beam, diffuse skylight, and total global ultraviolet irradiance are converted to daily ultraviolet index measurements. Daily…

Rate equation model of laser induced bias in uranium isotope ratios measured by resonance ionization mass spectrometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Isselhardt, B. H.; Prussin, S. G.; Savina, M. R.

2016-01-01

Resonance Ionization Mass Spectrometry (RIMS) has been developed as a method to measure uranium isotope abundances. In this approach, RIMS is used as an element-selective ionization process between uranium atoms and potential isobars without the aid of chemical purification and separation. The use of broad bandwidth lasers with automated feedback control of wavelength was applied to the measurement of the U-235/U-238 ratio to decrease laser-induced isotopic fractionation. In application, isotope standards are used to identify and correct bias in measured isotope ratios, but understanding laser-induced bias from first-principles can improve the precision and accuracy of experimental measurements. A rate equationmore » model for predicting the relative ionization probability has been developed to study the effect of variations in laser parameters on the measured isotope ratio. The model uses atomic data and empirical descriptions of laser performance to estimate the laser-induced bias expected in experimental measurements of the U-235/U-238 ratio. Empirical corrections are also included to account for ionization processes that are difficult to calculate from first principles with the available atomic data. Development of this model has highlighted several important considerations for properly interpreting experimental results.« less

Rate equation model of laser induced bias in uranium isotope ratios measured by resonance ionization mass spectrometry

DOE PAGES

Isselhardt, B. H.; Prussin, S. G.; Savina, M. R.; ...

2015-12-07

Resonance Ionization Mass Spectrometry (RIMS) has been developed as a method to measure uranium isotope abundances. In this approach, RIMS is used as an element-selective ionization process between uranium atoms and potential isobars without the aid of chemical purification and separation. The use of broad bandwidth lasers with automated feedback control of wavelength was applied to the measurement of the 235U/238U ratio to decrease laser-induced isotopic fractionation. In application, isotope standards are used to identify and correct bias in measured isotope ratios, but understanding laser-induced bias from first-principles can improve the precision and accuracy of experimental measurements. A rate equationmore » model for predicting the relative ionization probability has been developed to study the effect of variations in laser parameters on the measured isotope ratio. The model uses atomic data and empirical descriptions of laser performance to estimate the laser-induced bias expected in experimental measurements of the 235U/ 238U ratio. Empirical corrections are also included to account for ionization processes that are difficult to calculate from first principles with the available atomic data. As a result, development of this model has highlighted several important considerations for properly interpreting experimental results.« less

Outcome measurement of hand function following mirror therapy for stroke rehabilitation: A systematic review.

PubMed

Cantero-Téllez, Raquel; Naughton, Nancy; Algar, Lori; Valdes, Kristin

2018-02-28

Systematic review. Mirror therapy is a treatment used to address hand function following a stroke. Measurement of outcomes using appropriate assessment tools is crucial; however, many assessment options exist. The purpose of this study is to systematically review outcome measures that are used to assess hand function following mirror therapy after stroke and, in addition, to identify the psychometric and descriptive properties of the included measures and through the linking process determine if the outcome measures are representative of the International Classification of Functioning, Disability and Health (ICF). Following a comprehensive literature search, outcome measures used in the included studies were linked to the ICF and analyzed based on descriptive information and psychometric properties. Eleven studies met inclusion criteria and included 24 different assessment tools to measure hand or upper limb function. Most outcome measures used in the selected studies (63%) were rated by the evaluating therapist. Thirteen outcome measures (54%) linked to the ICF body function category and 10 measures (42%) linked to activities and participation. One outcome measure was linked to not defined, and all other ICF categories were not represented. A majority of outcome measures have been assessed for validity, reliability, and responsiveness, but responsiveness was the least investigated psychometric property. Current studies on mirror therapy after stroke are not consistent in the assessment tools used to determine hand function. Understanding of study outcomes requires analysis of the assessment tools. The outcome measures used in the included studies are not representative of personal and environmental factors, but tools linking to body functions and activities and participations provide important information on functional outcome. Integrating a combination of measures that are psychometrically sound and reflective of the ICF should be considered for assessment of

Silicon Isotopic Measurements in Desolvated Samples by MC-ICP-MS

NASA Astrophysics Data System (ADS)

Cardinal, D.; Alleman, L.; Ziegler, K.; de Jong, J.; Andre, L.

2002-12-01

Silicon, the most ubiquitous rock-forming element presents also a key role in biological processes. In particular, its biogeochemical cycle constitutes one of the most challenging issues in recent years due to its close relationship with the carbon cycle in marine environments (Tréguer et al., 1995; Ragueneau et al., 2000). The most recent silicon isotopic investigations on various natural samples have highlighted the great potential of this (palaeo)-proxy for oceanographers (De La Rocha et al., 1997, 1998). Better understanding the silicon isotope fractionation due to various biogeochemical processes can be achieved by facilitating its measurements through MC-ICPMS technique (De La Rocha et al., 2002; Alleman et al., 2002). In this regard we have developed an original method to analyze silicon isotopes under dry plasma conditions. We demonstrate that coupling a Nu Plasma MC-ICP-MS with a Cetac Aridus desolvator allows the rapid acquisition of natural silicon isotope abundances with high sensitivity and accuracy. To adequately correct for the mass fractionation occurring at the interface between the plasma source and the mass spectrometer line, we combine external normalization using Mg as a dopant with standard-sample bracketing using NBS-28 as the reference. With the desolvating nebulization system, the measurement of 28Si and 29Si isotopes is not hampered by significant interferences. δ29Si values are obtained with an accuracy and repeatability better than 0.1 \\permil. The accuracy has been successfully calibrated against the laser fluorination line technique (De La Rocha et al., 1996; Alleman et al., 2002). We could demonstrate that the isotopic fractionation that might occur in the plasma or the desolvator was adequately corrected by combining Mg isotopes and the sample-standard bracketing procedure. Moreover, the preservation of the Si isotopic signatures of the samples is validated by the different chemical sample treatments required by these two

Paloma: In-situ Measurement of The Elemental and Isotopic Composition of The Mars Atmosphere

NASA Astrophysics Data System (ADS)

Chassefiere, E.; Jambon, A.; Berthelier, J.-J.; Correia, J.-J.; Covinhes, J.; Goulpeau, G.; Leblanc, F.; Malique, Ch.; Sarda, P.; Schaetzel, P.; Sabroux, J.-C.; Ferry, C.; Richon, P.; Pineau, J.-F.; Desjean, M.-C.

The PALOMA instrument, presently under study in the frame of the NASA/CNES Mars exploration program, is devoted to the accurate measurement of isotopic and el- emental ratios in Mars atmosphere. It consists of a mass spectrometer coupled with a gas preparation line for separation of reactive and noble gas species, and noble gas species (and reactive gases) from each other, by chemical and cryogenic trapping, and possibly permeation techniques. This instrument, ranked among the most important four types of measurement recommended by the US Committee on Planetary and Lu- nar Exploration (COMPLEX), will be proposed as a part of the payload of the 07 NASA smart landers. The general objectives of PALOMA are to provide instanta- neous and time-varying patterns of noble gas isotopic spectra, and stable isotopes. Such measurements will allow to improve our general understanding of volatile cy- cles on Mars, and to better decipher the history of the atmosphere and climate. Past escape processes, exchanges between solid planet and atmosphere, post-accretional addition of volatil-rich matter from comets, are expected to have imprinted specific isotopic signatures. Although these signatures are strongly interlocked, a compara- tive Earth-Mars approach may allow to discriminate between them, and therefore to reconstruct the history of Martian volatiles. The evolution of atmospheric mass and composition may have had a major impact on climate evolution, e.g. through massive escape of carbon dioxide and water. In addition, precise measurements of isotopes in the present Mars atmosphere are the most promising way on the short term to confirm that SNC meteorites are from Martian origin. PALOMA also includes a small separate device for measuring ambient natural radioactivity, which might provide information about the presence of a near subsurface permafrost, possible residual volcanic activity, vertical mixing rate in the boundary layer.

Hand and Power Tools

DTIC Science & Technology

1998-01-01

equipped with a constant- pressure switch or control: drills; tappers; fastener drivers; horizontal, vertical, and angle grinders with wheels more than...hand-held power tools must be equipped with either a positive “on-off” control switch, a constant pressure switch , or a “lock-on” control: disc sanders...percussion tools with no means of holding accessories securely, must be equipped with a constant- pressure switch that will shut off the power when the

Effects of a new mild shampoo for preventing hair loss in Asian by a simple hand-held phototrichogram technique.

PubMed

Baek, J H; Lee, S Y; Yoo, M; Park, W-S; Lee, S J; Boo, Y C; Koh, J-S

2011-12-01

This study was conducted to evaluate the effects of a commercially available shampoo in Korean subjects with alopecia using a simple hand-held phototrichogram technique. Forty-four subjects with alopecia were enrolled and forty subjects continued for 16 weeks. In the test group, total hair counts increased significantly at weeks 8 and 16, and the number of shedding hair significantly decreased at week 16. Terminal hair counts significantly increased at week 8. In the control group, hair thickness and the number of vellus hairs significantly decreased at week 16. The number of total hairs significantly increased in the test group than in the control group at weeks 8 and 16. The number of shedding hairs significantly decreased in the test group than in the control group at week 16. Visual assessment using clinical digital images showed that the number of total hairs appeared to increase although there was no statistical significance. In this study, it was found that the test shampoo could prevent hair loss. © 2011 DERMAPRO Co Ltd. ICS © 2011 Society of Cosmetic Scientists and the Société Française de Cosmétologie.

A novel procedure for Rubidium separation and its isotope measurements on geological samples by MC-ICP-MS

NASA Astrophysics Data System (ADS)

Ma, J.; Zhang, Z.; Wei, G.; Zhang, L.

2017-12-01

A method including a novel column Rb separation procedure and high-precision Rb isotope measurement in geological materials by using multi-collector inductively coupled plasma mass spectrometry (MC-ICP-MS) in standard-sample-bracketing (SSB) mode has been developed. Sr-Spec resin was employed, in which the distribution coefficients for Rb, K, Ba and Sr are different in nitric acid, to sequentially separate them from the matrix. The dissolved samples were loaded on the column in 3 M HNO3, the main matrix such as Al, Ca, Fe, Mg, Mn and Na were removed by rinsing with 4.5 mL HNO3, Rb and K were then sequentially eluted by 3 M HNO3 in different volumes. After that, Ba was eluted by 8 M HNO3, and Sr was finally eluted by Milli-Q water. This enable us to collect the pure Rb, K, Ba and Sr one by one with recovery close to 100% for their isotopic compositions measurement on MC-ICP-MS. We here focus on Rb isotope measurement. The measurement using MC-ICP-MS yielded an internal precision for δ87Rb of < ± 0.03‰ (2SE), and the external precision was generally better than ± 0.06‰ (2SD) based on the long-term results of the Rb standard solutions NIST SRM 984. A series of geological rock standards, were analyzed using this method, and the results indicate significant Rb isotope differences in different geologic materials. This will provide a powerful tool to investigate Rb isotope fractionation during geological processes.Based on this method, Rb isotope compositions from a basaltic weathering profile were carried out. The data show the lighter Rb (85Rb) isotope is preferentially leached from the weathering profile and remains heavy Rb isotope (87Rb) in the weathered residues during the incipient weathering stage. From the moderate to advanced weathering stage, the significant variations of Rb isotope were observed and multiple factors, such as leaching, adsorption, desorption, and precipitation, should play important role in fractionating Rb isotope.

Subjective scaling of hand-arm vibration.

PubMed

Maeda, Setsuo; Shibata, Nobuyuki

2008-04-01

The purpose of this research was to establish a scale for comfort with regard to hand-arm vibration using the category judgment method and to validate the frequency-weighting method of the ISO 5349-1 standard. Experiments were conducted using random signals as stimuli. These stimuli consisted of three types of signal, namely designated stimulus F, with flat power spectrum density (PSD) ranging from 1 to 1,000 Hz, stimulus H with PSD which became 20 dB higher at 1,000 Hz than at 1 Hz, and stimulus L that had a PSD 20 dB lower at 1,000 Hz. These stimuli were selected from the specific spectrum patterns of hand-held vibration tools. These signals were modified by the Wh frequency weighting in accordance with ISO 5349-1, and the R.M.S. values were adjusted to be equal. In addition, the signal levels were varied over a range of five steps to create 15 kinds of individual stimuli. The subjects sat in front of a vibrator and grasped the mounted handle which exposed them to vertical vibrations after which they were asked to choose a numerical category to best indicate their perceived level of comfort (or otherwise) during each stimulus. From the experimental results of the category judgment method, the relationship between the psychological values and the frequency-weighted R.M.S. acceleration according to the ISO 5349-1 standard was obtained. It was found that the subjective response scaling of hand-arm vibration can be used for design-objective values of hand-held tool vibration.

A feasibility and efficacy trial of a hand-held humidification device in patients undergoing radiotherapy for head and neck cancer.

PubMed

Ghosh, Priyanka; Lazar, Ann A; Ryan, William R; Yom, Sue S

2017-08-01

This study aimed to evaluate the effects of warm-mist humidification during and after head and neck radiation therapy (HN RT) on quality of life (QOL), as measured by the M. D. Anderson Symptom Inventory-Head and Neck (MDASI-HN) HN score. A secondary aim was to compare QOL among compliers (≥60% of protocol-recommended usage) versus non-compliers. Twenty patients self-administered a hand-held, self-sterilizing humidification device for a recommended time of at least 15 min twice daily for 12 weeks. Patients completed the MDASI-HN instrument at RT start, after 6 weeks, and after 12 weeks. Compliance was reported weekly. The average HN score at baseline was 1.7 (SD = 1.8) and increased to 6.0 (SD = 1.6) after 6 weeks; this increase was much higher than anticipated and the primary endpoint could not be reached. However, compliers had an average of nearly two less HN symptoms (-1.8, 95% CI -4 to 0.2; p = 0.08) than non-compliers at 6 weeks and fewer symptoms at 12 weeks as well (-0.9, 95% CI -2.9 to 1.2; p = 0.39). The most common terms patients used to describe humidification were "helpful" and "soothing." Compliance with humidification during RT was associated with fewer reported HN symptoms and a strong trend to better QOL. Improvements were seen from compliance with occasional required use of a portable, inexpensive device. Our findings support continued efforts to reduce barriers to humidification, as an intervention that should be considered for standard HN RT clinical practice.

26 CFR 1.1223-1 - Determination of period for which capital assets are held.

Code of Federal Regulations, 2013 CFR

2013-04-01

... Gains and Losses § 1.1223-1 Determination of period for which capital assets are held. (a) The holding... determining gain or loss in the hands of the taxpayer as the property exchanged. However, this rule shall... in part in the hands of the taxpayer for determining gain or loss from a sale or exchange as it would...

26 CFR 1.1223-1 - Determination of period for which capital assets are held.

Code of Federal Regulations, 2014 CFR

2014-04-01

... Gains and Losses § 1.1223-1 Determination of period for which capital assets are held. (a) The holding... determining gain or loss in the hands of the taxpayer as the property exchanged. However, this rule shall... in part in the hands of the taxpayer for determining gain or loss from a sale or exchange as it would...

26 CFR 1.1223-1 - Determination of period for which capital assets are held.

Code of Federal Regulations, 2012 CFR

2012-04-01

... Gains and Losses § 1.1223-1 Determination of period for which capital assets are held. (a) The holding... determining gain or loss in the hands of the taxpayer as the property exchanged. However, this rule shall... in part in the hands of the taxpayer for determining gain or loss from a sale or exchange as it would...

26 CFR 1.1223-1 - Determination of period for which capital assets are held.

Code of Federal Regulations, 2011 CFR

2011-04-01

... Gains and Losses § 1.1223-1 Determination of period for which capital assets are held. (a) The holding... determining gain or loss in the hands of the taxpayer as the property exchanged. However, this rule shall... in part in the hands of the taxpayer for determining gain or loss from a sale or exchange as it would...

Quantitative Determination of Isotope Ratios from Experimental Isotopic Distributions

PubMed Central

Kaur, Parminder; O’Connor, Peter B.

2008-01-01

Isotope variability due to natural processes provides important information for studying a variety of complex natural phenomena from the origins of a particular sample to the traces of biochemical reaction mechanisms. These measurements require high-precision determination of isotope ratios of a particular element involved. Isotope Ratio Mass Spectrometers (IRMS) are widely employed tools for such a high-precision analysis, which have some limitations. This work aims at overcoming the limitations inherent to IRMS by estimating the elemental isotopic abundance from the experimental isotopic distribution. In particular, a computational method has been derived which allows the calculation of 13C/12C ratios from the whole isotopic distributions, given certain caveats, and these calculations are applied to several cases to demonstrate their utility. The limitations of the method in terms of the required number of ions and S/N ratio are discussed. For high-precision estimates of the isotope ratios, this method requires very precise measurement of the experimental isotopic distribution abundances, free from any artifacts introduced by noise, sample heterogeneity, or other experimental sources. PMID:17263354

Hand sensibility measures used by therapists.

PubMed

Mielke, K; Novak, C B; Mackinnon, S E; Feely, C A

1996-03-01

Sensory evaluations are frequently used to assess patients with functional loss resulting from nerve injury. The results of these tests are routinely utilized by hand surgeons as an indication for conservative management or surgical intervention in the evaluation of surgical outcome and in the determination of disability ratings. Reports in the literature regarding specific tests for sensibility show variation in their application. The purpose of this study was to evaluate which tests are used to evaluate hand sensibility and the techniques of application currently used by hand therapists. Two hundred members of the American Society of Hand Therapists were randomly selected and a survey was sent to these members. The results of this study identify the need to develop standardized protocols for sensory evaluations and the need for therapists to follow the standardized methods for administration of moving and static two-point discrimination, and Semmes-Weinstein monofilaments, if comparisons of results between centers are to be meaningful.

Non-destructive measurement of carbonic anhydrase activity and the oxygen isotope composition of soil water

NASA Astrophysics Data System (ADS)

Jones, Sam; Sauze, Joana; Ogée, Jérôme; Wohl, Steven; Bosc, Alexandre; Wingate, Lisa

2016-04-01

oxygen isotope composition of ambient CO2. This non-destructive approach was tested through laboratory incubations of air-dried soils that were re-wetted with water of known isotopic composition. Performance was assessed by comparing estimates of the soil water oxygen isotope composition derived from open chamber flux measurements with those measured in the irrigation water and soil water extracted following incubations. The influence of soil pH and bovine carbonic anhydrase additions on these estimates was also investigated. Coherent values were found between the soil water composition estimates obtained from the dual steady state approach and those measured for irrigation waters. Estimates of carbonic anhydrase activity made using this approach also reflected well artificial increases to the concentration of carbonic anhydrase and indicated that this activity was sensitive to soil pH.

Spectral contaminant identifier for off-axis integrated cavity output spectroscopy measurements of liquid water isotopes

NASA Astrophysics Data System (ADS)

Brian Leen, J.; Berman, Elena S. F.; Liebson, Lindsay; Gupta, Manish

2012-04-01

Developments in cavity-enhanced absorption spectrometry have made it possible to measure water isotopes using faster, more cost-effective field-deployable instrumentation. Several groups have attempted to extend this technology to measure water extracted from plants and found that other extracted organics absorb light at frequencies similar to that absorbed by the water isotopomers, leading to δ2H and δ18O measurement errors (Δδ2H and Δδ18O). In this note, the off-axis integrated cavity output spectroscopy (ICOS) spectra of stable isotopes in liquid water is analyzed to determine the presence of interfering absorbers that lead to erroneous isotope measurements. The baseline offset of the spectra is used to calculate a broadband spectral metric, mBB, and the mean subtracted fit residuals in two regions of interest are used to determine a narrowband metric, mNB. These metrics are used to correct for Δδ2H and Δδ18O. The method was tested on 14 instruments and Δδ18O was found to scale linearly with contaminant concentration for both narrowband (e.g., methanol) and broadband (e.g., ethanol) absorbers, while Δδ2H scaled linearly with narrowband and as a polynomial with broadband absorbers. Additionally, the isotope errors scaled logarithmically with mNB. Using the isotope error versus mNB and mBB curves, Δδ2H and Δδ18O resulting from methanol contamination were corrected to a maximum mean absolute error of 0.93 ‰ and 0.25 ‰ respectively, while Δδ2H and Δδ18O from ethanol contamination were corrected to a maximum mean absolute error of 1.22 ‰ and 0.22 ‰. Large variation between instruments indicates that the sensitivities must be calibrated for each individual isotope analyzer. These results suggest that the properly calibrated interference metrics can be used to correct for polluted samples and extend off-axis ICOS measurements of liquid water to include plant waters, soil extracts, wastewater, and alcoholic beverages. The general technique

Development of a Hand Held Thromboelastograph

DTIC Science & Technology

2015-01-01

documents will be referenced during the Entegrion PCM System design, verification and validation activities. EN 61010 -1:2010 (Edition3.0) Safety...requirements for electrical equipment for measurement, control, and laboratory use – Part 1: General requirements. EN 61010 -2-101:2002 Safety...IPC-A-610E Acceptability of Electronic Assemblies IPC 7711/21B Rework, Modification and Repair of Electronic Assemblies. IEC 62304:2006/AC:2008

Isotope Variations in Terrestrial Carbonates and Thermal Springs as Biomarkers: Analogs for Martian Processes

NASA Technical Reports Server (NTRS)

Socki, Richard A.; Gibson, Everett K., Jr.; Bissada, K. K.

2006-01-01

Stable isotope measurements of carbonate minerals contained within ALH84001 [1] suggest that fluids were present at 3.9 Gy on Mars [2, 3, 4, 5]. Both oxygen and carbon isotopes provide independent means of deciphering paleoenvironmental conditions at the time of carbonate mineral precipitation. In terrestrial carbonate rocks oxygen isotopes not only indicate the paleotemperature of the precipitating fluid, but also provide clues to environmental conditions that affected the fluid chemistry. Carbon isotopes, on the other hand, can indicate the presence or absence of organic compounds during precipitation (i.e. biogenically vs. thermogenically-generated methane), thus serving as a potential biomarker. We have undertaken a study of micro scale stable isotope variations measured in some terrestrial carbonates and the influence of organic compounds associated with the formation of these carbonates. Preliminary results indicate that isotope variations occur within narrow and discrete intervals, providing clues to paleoenvironmental conditions that include both biological and non-biological activity. These results carry implications for deciphering Martian isotope data and therefore potential biological prospecting on the planet Mars. Recently, Fourier Transform Spectrometer observations have detected methane occurring in the Martian atmosphere [6] that could be attributed to a possible biogenic source. Indeed, Mars Express has detected the presence of methane in the Martian atmosphere [7], with evidence indicating that methane abundances are greatest above those basins with high water concentrations.

Smart mug to measure hand's geometrical mechanical impedance.

PubMed

Hondori, Hossein Mousavi; Tech, Ang Wei

2011-01-01

A novel device, which looks like a mug, has been proposed for measuring the impedance of human hand. The device is designed to have convenient size and light weight similar to an ordinary coffee mug. It contains a 2-axis inertia sensor to monitor vibration and a small motor to carry an eccentric mass (m=100 gr, r=2 cm, rpm=600). The centrifugal force due to the rotating mass applies a dynamic force to the hand that holds the mug. Correlation of the acceleration signals with the perturbing force gives the geometrical mechanical impedance. Experimental results on a healthy subject shows that impedance is posture dependant while it changes with the direction of the applied perturbing force. For nine postures the geometrical impedance is obtained all of which have elliptical shapes. The method can be used for assessment of spasticity and monitoring stability in patients with stroke or similar problems.

Radiogenic Isotopes As Paleoceanographic Tracers in Deep-Sea Corals: Advances in TIMS Measurements of Pb Isotopes and Application to Southern Ocean Corals

NASA Astrophysics Data System (ADS)

Wilson, D. J.; van de Flierdt, T.; Bridgestock, L. J.; Paul, M.; Rehkamper, M.; Robinson, L. F.; Adkins, J. F.

2014-12-01

Deep-sea corals have emerged as a valuable archive of deep ocean paleoceanographic change, with uranium-series dating providing absolute ages and the potential for centennial resolution. In combination with measurements of radiocarbon, neodymium isotopes and clumped isotopes, this archive has recently been exploited to reconstruct changes in ventilation, water mass sourcing and temperature in relation to millennial climate change. Lead (Pb) isotopes in both corals and seawater have also been used to track anthropogenic inputs through space and time and to trace transport pathways within the oceans. Better understanding of the oceanic Pb cycle is emerging from the GEOTRACES programme. However, while Pb isotopes have been widely used in environmental studies, their full potential as a (pre-anthropogenic) paleoceanographic tracer remains to be exploited. In deep-sea corals, challenges exist from low Pb concentrations in aragonite in comparison to secondary coatings, the potential for contamination, and the efficient elemental separation required for measurement by thermal ionisation mass spectrometry (TIMS). Here we discuss progress in measuring Pb isotopes in coral aragonite using a 207Pb-204Pb double spike on a ThermoFinnigan Triton TIMS. For a 2 ng NIST-981 Pb standard, the long term reproducibility (using 1011 Ω resistors) is ~1000 ppm (2 s.d.) on 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios. We now show that using a new 1012 Ω resistor to measure the small 204Pb beam improves the internal precision on these ratios from ~500 ppm (2 s.e.) to ~250 ppm (2 s.e.) and we envisage a potential improvement in the long term reproducibility as a consequence. We further assess the internal precision and external reproducibility of our method using a BCR-2 rock standard and an in-house coral standard. Preliminary evidence on the application of this method to natural samples is derived from cleaning experiments and replication tests on deep-sea corals from the Southern

Carbon and Hydrogen Isotope Measurements of Alcohols and Organic Acids by Online Pyroprobe-GC-IRMS

NASA Technical Reports Server (NTRS)

Socki, Richard A.; Fu, Qi; Niles, Paul B.; Gibson, Everett K., Jr.

2012-01-01

The detection of methane in the atmosphere of Mars, combined with evidence showing widespread water-rock interaction during martian history, suggests that the production of methane on Mars may be the result of mineral surface-catalyzed CO2 and or CO reduction during Fisher-Tropsch Type (FTT) reactions. A better understanding of these reaction pathways and corresponding C and H isotope fractionations is critical to deciphering the synthesis of organic compounds produced under abiotic hydrothermal conditions. Described here is a technique for the extraction and analysis of both C and H isotopes from alcohols (C1-C4) and organic acids (C1-C6). This work is meant to provide a "proof of concept" for making meaningful isotope measurements on complex mixtures of solid-phase hydrocarbons and other intermediary products produced during high-temperature and high-pressure synthesis on mineral-catalyzed surfaces. These analyses are conducted entirely "on-line" utilizing a CDS model 5000 Pyroprobe connected to a Thermo Trace GC Ultra that is interfaced with a Thermo MAT 253 isotope ratio mass spectrometer operating in continuous flow mode. Also, this technique is designed to carry a split of the GC-separated product to a DSQ II quadrupole mass spectrometer as a means of making semi-quantitative compositional measurements. Therefore, both chemical and isotopic measurements can be carried out on the same sample.

Measurement of picosecond lifetimes in neutron-rich Xe isotopes

NASA Astrophysics Data System (ADS)

Ilieva, S.; Kröll, Th.; Régis, J.-M.; Saed-Samii, N.; Blanc, A.; Bruce, A. M.; Fraile, L. M.; de France, G.; Hartig, A.-L.; Henrich, C.; Ignatov, A.; Jentschel, M.; Jolie, J.; Korten, W.; Köster, U.; Lalkovski, S.; Lozeva, R.; Mach, H.; Mǎrginean, N.; Mutti, P.; Paziy, V.; Regan, P. H.; Simpson, G. S.; Soldner, T.; Thürauf, M.; Ur, C. A.; Urban, W.; Warr, N.

2016-09-01

Background: Lifetimes of nuclear excited states in fission fragments have been studied in the past following isotope separation, thus giving access mainly to the fragments' daughters and only to long-lived isomeric states in the primary fragments. For the first time now, short-lived excited states in the primary fragments, produced in neutron-induced prompt fission of 235U and 241Pu, were studied within the EXILL&FATIMA campaign at the intense neutron-beam facility of the Institute Laue-Langevin in Grenoble. Purpose: We aim to investigate the quadrupole collective properties of neutron-rich even-even 138,140,142Xe isotopes lying between the double shell closure N =82 and Z =50 and a deformed region with octupole collectivity. Method: The γ rays emitted from the excited fragments were detected with a mixed array consisting of 8 HPGe EXOGAM Clover detectors (EXILL) and 16 LaBr3(Ce) fast scintillators (FATIMA). The detector system has the unique ability to select the interesting fragment making use of the high resolution of the HPGe detectors and determine subnanosecond lifetimes using the fast scintillators. For the analysis the generalized centroid difference method was used. Results: We show that quadrupole collectivity increases smoothly with increasing neutron number above the closed N =82 neutron shell. Our measurements are complemented by state-of-the-art theory calculations based on shell-model descriptions. Conclusions: The observed smooth increase in quadrupole collectivity is similar to the evolution seen in the measured masses of the xenon isotopic chain and is well reproduced by theory. This behavior is in contrast to higher Z even-even nuclei where abrupt change in deformation occurs around N =90 .

Mobile measurement of methane: plumes, isotopes and inventory verification

NASA Astrophysics Data System (ADS)

Lowry, D.; Zazzeri, G.; Fisher, R. E.; France, J.; Al-Shalaan, A.; Lanoisellé, M.; Nisbet, E. G.

2015-12-01

Since 2013 the RHUL group has been identifying methane plumes from major UK sources using a Picarro 2301 coupled to the A0941 mobile module. Once identified the plumes have been sampled by filling Tedlar or Flexfoil bags for later carbon isotopic analysis by high-precision IRMS. This method has ben successfully deployed to isotopically characterize the main anthropogenic methane emitters in the UK (natural gas, coal, landfill, wastewater treatment, cattle; Zazzeri et al., 2015) and during overseas campaigns in eastern Australia (coal, cattle, legacy gas wells) and Kuwait (landfill, wastewater treatment, oil refineries, cattle, camels). This has identified strong similarities of isotopic signature for some sources (landfill, cattle), but large variations for others (natural gas, coal), which must be isotopically resolved at regional scale. Both landfill and natural gas emissions in SE England have tightly-constrained δ13C signatures, averaging -58 ± 3‰ and -36 ± 2‰, respectively, the latter being characteristic of homogenised North Sea gas supply. In contrast, signatures for coal mines in England and Wales fall in a range of 51.2 ± 0.3‰ to 30.9 ± 1.4‰, but can be tightly constrained by region. On a local scale in west London, repeat surveys in the boroughs of Hounslow and Runnymede have been made for comparison with the latest 1x1 km grid UK inventories for 2009 and 2012, which are subdivided by UNECE categories. An excess methane map can be derived for comparison with inventory emissions maps by identifying daily background and binning the excess values from mobile measurements by grid-square. This shows that the spatial distribution of emissions in the UK 2012 inventory is a big improvement on that of 2009. It also suggests that there is an overestimation of emissions from old landfills (closed before 2000 and reliant on a topsoil cap for oxidation), and an underestimation on emissions from currently active landfill cells. Zazzeri, G. et al. (2015

Measurement of infiltration rates in urban sewer systems by use of oxygen isotopes.

PubMed

De Bénédittis, J; Bertrand-Krajewski, J L

2005-01-01

The paper presents the principle of a method to measure infiltration rates in sewer systems based on the use of oxygen isotopes and its application in Lyon (France). In the urban area of Lyon, significant differences in delta 18O that can reach 3 per thousand are observed between the oxygen isotopic compositions of groundwater originating from Rhone, Saone and from their associated alluvial aquifers. Drinking water supplying Lyon results mainly from pumping in the Rhone alluvial aquifer. Therefore, in some areas, the difference of isotopic composition between wastewater resulting from the consumption of drinking water and local groundwater can be used to measure infiltration in sewer systems. The application in the catchment of Ecully shows that the infiltration flow rate presents strong fluctuations at an hourly scale: it varies between 15 and 40 m3/h. This variability could be explained by non-constant discharges of pumping and by variations of the water level in the sewer.

Methane clumped isotopes: Progress and potential for a new isotopic tracer

DOE Office of Scientific and Technical Information (OSTI.GOV)

Douglas, Peter M. J.; Stolper, Daniel A.; Eiler, John M.

The isotopic composition of methane is of longstanding geochemical interest, with important implications for understanding hydrocarbon systems, atmospheric greenhouse gas concentrations, the global carbon cycle, and life in extreme environments. Recent analytical developments focusing on multiply substituted isotopologues (‘clumped isotopes’) are opening a potentially valuable new window into methane geochemistry. When methane forms in internal isotopic equilibrium, clumped isotopes can provide a direct record of formation temperature, making this property particularly valuable for identifying different methane origins. However, it has also become clear that in certain settings methane clumped isotope measurements record kinetic rather than equilibrium isotope effects. Here wemore » present a substantially expanded dataset of methane clumped isotope analyses, and provide a synthesis of the current interpretive framework for this parameter. We review different processes affecting methane clumped isotope compositions, describe the relationships between conventional isotope and clumped isotope data, and summarize the types of information that this measurement can provide in different Earth and planetary environments.« less

Use of hand-held computers to determine the relative contribution of different cognitive, attitudinal, social, and organizational factors on health care workers' decision to decontaminate hands.

PubMed

Lee, Karen; Burnett, Emma; Morrison, Kenny; Ricketts, Ian

2014-02-01

Observational and survey methods have limitations in measuring hand hygiene behavior. The ability of a personal digital assistant to anonymously gather data at the point of decision making could potentially address these. Participants were provided with a personal digital assistant to be used for three 2-hour periods and asked to rate influential factors of the Health Belief Model (HBM). Participants were also required to enter what they thought they should do and what they actually did. A total of 741 hand hygiene opportunities was recorded. All HBM constructs were higher for hand hygiene opportunities where there was compliance versus noncompliance, with a significant difference for patient pressure, my risk, perceived benefits, perceived seriousness, and availability of good facilities. Only 20% of doctors, 28% of nurses, and 66% of physiotherapists always did what they thought they should. There was no correlation between self-reported and actual compliance. The HBM appeared to be a useful theoretical framework. Surprisingly, participants rated their compliance as high despite having recorded instances where they did not do what they thought they should do. This suggests that staff may have a different definition of compliance than strict observation of the guidelines. Copyright © 2014 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Mosby, Inc. All rights reserved.

[Design of hand-held heart rate variability acquisition and analysis system].

PubMed

Li, Kaiyuan; Wang, Buqing; Wang, Weidong

2012-07-01

A design of handheld heart rate variability acquisition and analysis system is proposed. The system collects and stores the patient's ECG every five minutes through both hands touching on the electrodes, and then -uploads data to a PC through USB port. The system uses software written in LabVIEW to analyze heart rate variability parameters, The parameters calculated function is programmed and generated to components in Matlab.

Measuring hand function in the young child.

PubMed

Ho, Emily S

2010-01-01

Assessing outcomes is vital in any hand therapy practice setting, as it is the primary method of determining whether or not a treatment program is working. In the pediatric population, determining improvements in hand function can be challenging. The author describes using a developmental perspective to evaluate hand function for infants and young children. The utilization of a consistent approach to play along with standard toys is described in this article as a method to evaluate the quality of hand function throughout developmental grasp patterns. Copyright © 2010 Hanley & Belfus. Published by Elsevier Inc. All rights reserved.

Polyatomic interferences on high precision uranium isotope ratio measurements by MC-ICP-MS: Applications to environmental sampling for nuclear safeguards

DOE PAGES

Pollington, Anthony D.; Kinman, William S.; Hanson, Susan K.; ...

2015-09-04

Modern mass spectrometry and separation techniques have made measurement of major uranium isotope ratios a routine task; however accurate and precise measurement of the minor uranium isotopes remains a challenge as sample size decreases. One particular challenge is the presence of isobaric interferences and their impact on the accuracy of minor isotope 234U and 236U measurements. Furthermore, we present techniques used for routine U isotopic analysis of environmental nuclear safeguards samples and evaluate polyatomic interferences that negatively impact accuracy as well as methods to mitigate their impacts.

Measurements of Interaction Cross Sections for 19-27F Isotopes

NASA Astrophysics Data System (ADS)

Homma, Akira; Takechi, Maya; Ohtsubo, Takashi; Nishimura, Daiki; Fukuda, Mitsunori; Suzuki, Takeshi; Yamaguchi, Takayuki; Kuboki, Takamasa; Ozawa, Akira; Suzuki, Sinji; Ooishi, Hiroto; Moriguchi, Tetsuaki; Sumikawa, Takashi; Geissel, H.; Aoi, Nori; Chen, Rui-jiu; Fang, De-Qing; Fukuda, Naoki; Fukuoka, Shota; Furuki, Hisahiro; Inaba, Naruki; Ishibashi, Nobuyuki; Ito, Takeshi; Izumikawa, Takuji; Kameda, Daisuke; Kubo, Toshiyuki; Lantz, M.; Lee, C. S.; Ma, Yu-Gang; Mihara, Mototsugu; Momota, Satao; Nagae, Daisuke; Nishikiori, Ryo; Niwa, Takahiro; Ohnishi, Tetsuya; Okumura, Kimitake; Ogura, Toshiyuki; Nagashima, Masayuki; Sakurai, Hiroyoshi; Sato, Kanae; Shimbara, Yoshiriro; Suzuki, Hiroshi; Takeda, Hiroyuki; Takeuchi, Satoshi; Tanaka, Kenji; Uenishi, Hideaki; Winkler, M.; Yanagisawa, Yoshiyuki

Interaction cross sections (σI) and reaction cross sections (σR) are physical quantities which are strongly related to the nuclear size. In our previous study of σI for Ne isotopes, the deformation features of neutron-rich Ne isotopes in the so-called "island of inversion" region have been successfully observed, and also the formation of the deformed halo structure in 31Ne has been indicated. In this study, σI for 19-27F, up to the vicinity of the island of inversion have been measured at around 240A MeV using BigRIPS at RIBF, RIKEN. Our preliminary results are slightly larger than A1/3 systematics and some of the data could be explained by nuclear deformation.

The use of hand-held 35 mm color infrared imagery for estimates of suspended solids - A progress report. [in water pollution monitoring

NASA Technical Reports Server (NTRS)

Miller, W. F.; Whisler, F. D.; Robinette, H. R.; Finnie, D.; Cannon, T.

1975-01-01

A cost-effective aerial surveillance technique is proposed for detection and identification of suspended solids which would be operational for both governmental monitoring organizations and private individuals operating catfish farms. Sixteen catfish ponds were flown daily for seven days using two hand-held 35 mm cameras with both Kodachrome X and Ektachrome infrared film. Hue, value, and chroma designations were recorded for each pond on each date by three interpreters, and the accepted color was that recorded by at least two of the interpreters, or if there was a three hue range, the median was accepted. Relations between suspended solids and color designations were analyzed graphically, and chroma was discarded due to an apparent lack of correlation. The data obtained were then analyzed by multiple regression. Significant correlations were revealed between hue and value and total and inorganic suspended solids. If perfected, this technique could be developed to sufficent accuracy for large-scale reconnaissance surveys to monitor the quality of rivers and streams.

The Rubber Hand Illusion: Feeling of Ownership and Proprioceptive Drift Do Not Go Hand in Hand

PubMed Central

Rohde, Marieke; Di Luca, Massimiliano; Ernst, Marc O.

2011-01-01

In the Rubber Hand Illusion, the feeling of ownership of a rubber hand displaced from a participant's real occluded hand is evoked by synchronously stroking both hands with paintbrushes. A change of perceived finger location towards the rubber hand (proprioceptive drift) has been reported to correlate with this illusion. To measure the time course of proprioceptive drift during the Rubber Hand Illusion, we regularly interrupted stroking (performed by robot arms) to measure perceived finger location. Measurements were made by projecting a probe dot into the field of view (using a semi-transparent mirror) and asking participants if the dot is to the left or to the right of their invisible hand (Experiment 1) or to adjust the position of the dot to that of their invisible hand (Experiment 2). We varied both the measurement frequency (every 10 s, 40 s, 120 s) and the mode of stroking (synchronous, asynchronous, just vision). Surprisingly, with frequent measurements, proprioceptive drift occurs not only in the synchronous stroking condition but also in the two control conditions (asynchronous stroking, just vision). Proprioceptive drift in the synchronous stroking condition is never higher than in the just vision condition. Only continuous exposure to asynchronous stroking prevents proprioceptive drift and thus replicates the differences in drift reported in the literature. By contrast, complementary subjective ratings (questionnaire) show that the feeling of ownership requires synchronous stroking and is not present in the asynchronous stroking condition. Thus, subjective ratings and drift are dissociated. We conclude that different mechanisms of multisensory integration are responsible for proprioceptive drift and the feeling of ownership. Proprioceptive drift relies on visuoproprioceptive integration alone, a process that is inhibited by asynchronous stroking, the most common control condition in Rubber Hand Illusion experiments. This dissociation implies that

Absolute Reliability and Concurrent Validity of Hand Held Dynamometry and Isokinetic Dynamometry in the Hip, Knee and Ankle Joint: Systematic Review and Meta-analysis

PubMed Central

Chamorro, Claudio; Armijo-Olivo, Susan; De la Fuente, Carlos; Fuentes, Javiera; Javier Chirosa, Luis

2017-01-01

Abstract The purpose of the study is to establish absolute reliability and concurrent validity between hand-held dynamometers (HHDs) and isokinetic dynamometers (IDs) in lower extremity peak torque assessment. Medline, Embase, CINAHL databases were searched for studies related to psychometric properties in muscle dynamometry. Studies considering standard error of measurement SEM (%) or limit of agreement LOA (%) expressed as percentage of the mean, were considered to establish absolute reliability while studies using intra-class correlation coefficient (ICC) were considered to establish concurrent validity between dynamometers. In total, 17 studies were included in the meta-analysis. The COSMIN checklist classified them between fair and poor. Using HHDs, knee extension LOA (%) was 33.59%, 95% confidence interval (CI) 23.91 to 43.26 and ankle plantar flexion LOA (%) was 48.87%, CI 35.19 to 62.56. Using IDs, hip adduction and extension; knee flexion and extension; and ankle dorsiflexion showed LOA (%) under 15%. Lower hip, knee, and ankle LOA (%) were obtained using an ID compared to HHD. ICC between devices ranged between 0.62, CI (0.37 to 0.87) for ankle dorsiflexion to 0.94, IC (0.91to 0.98) for hip adduction. Very high correlation were found for hip adductors and hip flexors and moderate correlations for knee flexors/extensors and ankle plantar/dorsiflexors. PMID:29071305

Characterization of a high performance ultra-thin heat pipe cooling module for mobile hand held electronic devices

NASA Astrophysics Data System (ADS)

Ahamed, Mohammad Shahed; Saito, Yuji; Mashiko, Koichi; Mochizuki, Masataka

2017-11-01

In recent years, heat pipes have been widely used in various hand held mobile electronic devices such as smart phones, tablet PCs, digital cameras. With the development of technology these devices have different user friendly features and applications; which require very high clock speeds of the processor. In general, a high clock speed generates a lot of heat, which needs to be spreaded or removed to eliminate the hot spot on the processor surface. However, it is a challenging task to achieve proper cooling of such electronic devices mentioned above because of their confined spaces and concentrated heat sources. Regarding this challenge, we introduced an ultra-thin heat pipe; this heat pipe consists of a special fiber wick structure named as "Center Fiber Wick" which can provide sufficient vapor space on the both sides of the wick structure. We also developed a cooling module that uses this kind of ultra-thin heat pipe to eliminate the hot spot issue. This cooling module consists of an ultra-thin heat pipe and a metal plate. By changing the width, the flattened thickness and the effective length of the ultra-thin heat pipe, several experiments have been conducted to characterize the thermal properties of the developed cooling module. In addition, other experiments were also conducted to determine the effects of changes in the number of heat pipes in a single module. Characterization and comparison of the module have also been conducted both experimentally and theoretically.

A quantitative evaluation of spurious results in the infrared spectroscopic measurement of CO2 isotope ratios

NASA Astrophysics Data System (ADS)

Mansfield, C. D.; Rutt, H. N.

2002-02-01

The possible generation of spurious results, arising from the application of infrared spectroscopic techniques to the measurement of carbon isotope ratios in breath, due to coincident absorption bands has been re-examined. An earlier investigation, which approached the problem qualitatively, fulfilled its aspirations in providing an unambiguous assurance that 13C16O2/12C16O2 ratios can be confidently measured for isotopic breath tests using instruments based on infrared absorption. Although this conclusion still stands, subsequent quantitative investigation has revealed an important exception that necessitates a strict adherence to sample collection protocol. The results show that concentrations and decay rates of the coincident breath trace compounds acetonitrile and carbon monoxide, found in the breath sample of a heavy smoker, can produce spurious results. Hence, findings from this investigation justify the concern that breath trace compounds present a risk to the accurate measurement of carbon isotope ratios in breath when using broadband, non-dispersive, ground state absorption infrared spectroscopy. It provides recommendations on the length of smoking abstention required to avoid generation of spurious results and also reaffirms, through quantitative argument, the validity of using infrared absorption spectroscopy to measure CO2 isotope ratios in breath.

Isometric hand grip strength measured by the Nintendo Wii Balance Board - a reliable new method.

PubMed

Blomkvist, A W; Andersen, S; de Bruin, E D; Jorgensen, M G

2016-02-03

Low hand grip strength is a strong predictor for both long-term and short-term disability and mortality. The Nintendo Wii Balance Board (WBB) is an inexpensive, portable, wide-spread instrument with the potential for multiple purposes in assessing clinically relevant measures including muscle strength. The purpose of the study was to explore intrarater reliability and concurrent validity of the WBB by comparing it to the Jamar hand dynamometer. Intra-rater test-retest cohort design with randomized validity testing on the first session. Using custom WBB software, thirty old adults (69.0 ± 4.2 years of age) were studied for reproducibility and concurrent validity compared to the Jamar hand dynamometer. Reproducibility was tested for dominant and non-dominant hands during the same time-of-day, one week apart. Intraclass correlation coefficient (ICC) and standard error of measurement (SEM) and limits of agreement (LOA) were calculated to describe relative and absolute reproducibility respectively. To describe concurrent validity, Pearson's product-moment correlation and ICC was calculated. Reproducibility was high with ICC values of >0.948 across all measures. Both SEM and LOA were low (0.2-0.5 kg and 2.7-4.2 kg, respectively) in both the dominant and non-dominant hand. For validity, Pearson correlations were high (0.80-0.88) and ICC values were fair to good (0.763-0.803). Reproducibility for WBB was high for relative measures and acceptable for absolute measures. In addition, concurrent validity between the Jamar hand dynamometer and the WBB was acceptable. Thus, the WBB may be a valid instrument to assess hand grip strength in older adults.

A drift correction optimization technique for the reduction of the inter-measurement dispersion of isotope ratios measured using a multi-collector plasma mass spectrometer

NASA Astrophysics Data System (ADS)

Doherty, W.; Lightfoot, P. C.; Ames, D. E.

2014-08-01

The effects of polynomial interpolation and internal standardization drift corrections on the inter-measurement dispersion (statistical) of isotope ratios measured with a multi-collector plasma mass spectrometer were investigated using the (analyte, internal standard) isotope systems of (Ni, Cu), (Cu, Ni), (Zn, Cu), (Zn, Ga), (Sm, Eu), (Hf, Re) and (Pb, Tl). The performance of five different correction factors was compared using a (statistical) range based merit function ωm which measures the accuracy and inter-measurement range of the instrument calibration. The frequency distribution of optimal correction factors over two hundred data sets uniformly favored three particular correction factors while the remaining two correction factors accounted for a small but still significant contribution to the reduction of the inter-measurement dispersion. Application of the merit function is demonstrated using the detection of Cu and Ni isotopic fractionation in laboratory and geologic-scale chemical reactor systems. Solvent extraction (diphenylthiocarbazone (Cu, Pb) and dimethylglyoxime (Ni) was used to either isotopically fractionate the metal during extraction using the method of competition or to isolate the Cu and Ni from the sample (sulfides and associated silicates). In the best case, differences in isotopic composition of ± 3 in the fifth significant figure could be routinely and reliably detected for Cu65/63 and Ni61/62. One of the internal standardization drift correction factors uses a least squares estimator to obtain a linear functional relationship between the measured analyte and internal standard isotope ratios. Graphical analysis demonstrates that the points on these graphs are defined by highly non-linear parametric curves and not two linearly correlated quantities which is the usual interpretation of these graphs. The success of this particular internal standardization correction factor was found in some cases to be due to a fortuitous, scale dependent