Detecting Life and Biology-Related Parameters on Mars
NASA Technical Reports Server (NTRS)
Levin, Gilbet V.; Miller, Joseph D.; Straat, Patricia A.; Lodder, Robert; Hoover, Richard B.
2007-01-01
An integrated, miniaturized, low-power instrument capable of the detection and early characterization of microbial life in the soil of Mars is proposed. Based on the detection apd monitoring of on-going metabolism as being the surest evidence for extant life, the experiments will probe for chirality in metabolism, for circadian rhythm, and for photosynthesis. However, the instrument package will also be able to detect biosignatures and a variety of other physical and chemical parameters of the Martian surface that have significance for life. These include the presence and the physical state of water, the existence of an oxidant, the pH and the penetrability of the soil. Using the legacy of the 1976 Viking Labeled Release (LR) life detection experiment in conjunction with state-of-the-art laser diode spectral analysis, the instrument can be flown stand-alone, with or without a rover, or as part of an MSL-type mission. Sterility for experiment integrity and for planetary protection is provided.
Stealth life detection instruments aboard Curiosity
NASA Astrophysics Data System (ADS)
Levin, Gilbert V.
2012-10-01
NASA has often stated (e.g. MSL Science Corner1) that it's Mars Science Laboratory (MSL), "Curiosity," Mission to Mars carries no life detection experiments. This is in keeping with NASA's 36-year explicit ban on such, imposed immediately after the 1976 Viking Mission to Mars. The space agency attributes the ban to the "ambiguity" of that Mission's Labeled Release (LR) life detection experiment, fearing an adverse effect on the space program should a similar "inconclusive" result come from a new robotic quest. Yet, despite the NASA ban, this author, the Viking LR Experimenter, contends there are "stealth life detection instruments" aboard Curiosity. These are life detection instruments in the sense that they can free the Viking LR from the pall of ambiguity that has held it prisoner so long. Curiosity's stealth instruments are those seeking organic compounds, and the mission's high-resolution camera system. Results from any or all of these devices, coupled with the Viking LR data, can confirm the LR's life detection claim. In one possible scenario, Curiosity can, of itself, completely corroborate the finding of life on Mars. MSL has just successfully landed on Mars. Hopefully, its stealth confirmations of life will be reported shortly.
No Organic Compounds on Mars? Understanding the Structure of Spiral Galaxies
NASA Technical Reports Server (NTRS)
Morrison, Nancy D.; Morrison, David
1977-01-01
A prime goal of the Viking missions to Mars is to search for life on that planet. Each of the two landers incorporate three specific life-detection experiments, and all have operated successfully. However, as any newspaper reader knows, the results are ambiguous, in that some experiments suggest a highly active martian biology while others appear to indicate that the samples are sterile. It would be premature to conclude from the results of the biological experiments that martian life forms have definitely been detected. In addition, the picture is clouded by unexpected results from another Viking experiment, which is designed to detect organic and inorganic chemical compounds in the martian soil. In Science for 1 October 1976, K. Biemann of MIT and ten of his colleagues report the first results from the Viking 1 Gas-Chromatograph/Mass Spectrometer (GCMS) experiment.
The carbon-assimilation experiment - The Viking Mars Lander.
NASA Technical Reports Server (NTRS)
Horowitz, N. H.; Hubbard, J. S.; Hobby, G. L.
1972-01-01
The carbon-assimilation experiment detects life in soils by measuring the incorporation of carbon from carbon-14 monoxide and carbon-14 dioxide into organic matter. It is based on the premise that Martian life, if it exists, is carbonaceous and exchanges carbon with the atmosphere, as do all terrestrial organisms. It is especially sensitive for photosynthesizing cells, but it detects heterotrophs also. The experiment has the particular advantage that it can be carried out under essentially Martian conditions of temperature, pressure, atmospheric composition, and water abundance.
NASA Astrophysics Data System (ADS)
Dillon, James; Quinn, R. C.
2010-01-01
The Viking Mars landers of 1976 conducted three biology experiments designed to detect the presence of microbial life in the Martian surface. The gas exchange experiment carried out by the Viking landers periodically sampled the gaseous headspace of Mars soil samples saturated with an organic/inorganic aqueous mixture, M4 nutrient. A gas chromatograph measured the change in concentrations of N2, O2, CO2, Kr, H2, and CH4 over various time intervals. The presence of metabolically active microbial life would be confirmed by the consumption or release of one of these gases. A significant release of O2 was detected after the addition of nutrient, however since the Gas Chromatograph - Mass Spectrometer experiment did not detect organics in the soil, this rapid release of O2 could not be attributed to microbial life, but rather a chemical reaction. The recent discovery of the oxidizer perchlorate in the Martian soil by the Phoenix Mars lander was investigated as the principal cause of this O2 release detected by the Viking gas exchange experiment. A variety of oxychloride salts ranging from hypochlorite to perchlorate were examined under conditions similar to the Viking experiment in order to determine if a rapid release of O2 would be detected upon addition of M4 nutrient. No oxychloride species examined decomposed with the kinetics required to support an oxychloride as the cause of the O2 response detected by the Viking experiment.
Levin, Gilbert V; Straat, Patricia Ann
2016-10-01
The 1976 Viking Labeled Release (LR) experiment was positive for extant microbial life on the surface of Mars. Experiments on both Viking landers, 4000 miles apart, yielded similar, repeatable, positive responses. While the authors eventually concluded that the experiment detected martian life, this was and remains a highly controversial conclusion. Many believe that the martian environment is inimical to life and the LR responses were nonbiological, attributed to an as-yet-unidentified oxidant (or oxidants) in the martian soil. Unfortunately, no further metabolic experiments have been conducted on Mars. Instead, follow-on missions have sought to define the martian environment, mostly searching for signs of water. These missions have collected considerable data regarding Mars as a habitat, both past and present. The purpose of this article is to consider recent findings about martian water, methane, and organics that impact the case for extant life on Mars. Further, the biological explanation of the LR and recent nonbiological hypotheses are evaluated. It is concluded that extant life is a strong possibility, that abiotic interpretations of the LR data are not conclusive, and that, even setting our conclusion aside, biology should still be considered as an explanation for the LR experiment. Because of possible contamination of Mars by terrestrial microbes after Viking, we note that the LR data are the only data we will ever have on biologically pristine martian samples. Key Words: Extant life on Mars-Viking Labeled Release experiment-Astrobiology-Extraterrestrial life-Mars. Astrobiology 16, 798-810.
2000-02-01
HIDS] Program: Power Drive Train Crack Detection Diagnostics and Prognostics ife Usage Monitoring and Damage Tolerance; Techniques, Methodologies, and...and Prognostics , Life Usage Monitoring , and Damage Tolerance; Techniques, Methodologies, and Experiences Andrew Hess Harrison Chin William Hardman...continuing program and deployed engine monitoring systems in fixed to evaluate helicopter diagnostic, prognostic , and wing aircraft, notably on the A
A novel approach to simulate chest wall micro-motion for bio-radar life detection purpose
NASA Astrophysics Data System (ADS)
An, Qiang; Li, Zhao; Liang, Fulai; Chen, Fuming; Wang, Jianqi
2016-10-01
Volunteers are often recruited to serve as the detection targets during the research process of bio-radar life detection technology, in which the experiment results are highly susceptible to the physical status of different individuals (shape, posture, etc.). In order to objectively evaluate the radar system performance and life detection algorithms, a standard detection target is urgently needed. The paper first proposed a parameter quantitatively controllable system to simulate the chest wall micro-motion caused mainly by breathing and heart beating. Then, the paper continued to analyze the material and size selection of the scattering body mounted on the simulation system from the perspective of back scattering energy. The computational electromagnetic method was employed to determine the exact scattering body. Finally, on-site experiments were carried out to verify the reliability of the simulation platform utilizing an IR UWB bioradar. Experimental result shows that the proposed system can simulate a real human target from three aspects: respiration frequency, amplitude and body surface scattering energy. Thus, it can be utilized as a substitute for a human target in radar based non-contact life detection research in various scenarios.
The Case for Extant Life on Mars and Its Possible Detection by the Viking Labeled Release Experiment
NASA Astrophysics Data System (ADS)
Levin, Gilbert V.; Straat, Patricia Ann
2016-10-01
The 1976 Viking Labeled Release (LR) experiment was positive for extant microbial life on the surface of Mars. Experiments on both Viking landers, 4000 miles apart, yielded similar, repeatable, positive responses. While the authors eventually concluded that the experiment detected martian life, this was and remains a highly controversial conclusion. Many believe that the martian environment is inimical to life and the LR responses were nonbiological, attributed to an as-yet-unidentified oxidant (or oxidants) in the martian soil. Unfortunately, no further metabolic experiments have been conducted on Mars. Instead, follow-on missions have sought to define the martian environment, mostly searching for signs of water. These missions have collected considerable data regarding Mars as a habitat, both past and present. The purpose of this article is to consider recent findings about martian water, methane, and organics that impact the case for extant life on Mars. Further, the biological explanation of the LR and recent nonbiological hypotheses are evaluated. It is concluded that extant life is a strong possibility, that abiotic interpretations of the LR data are not conclusive, and that, even setting our conclusion aside, biology should still be considered as an explanation for the LR experiment. Because of possible contamination of Mars by terrestrial microbes after Viking, we note that the LR data are the only data we will ever have on biologically pristine martian samples.
Hwang, J Y; Kang, J M; Jang, Y W; Kim, H
2004-01-01
Novel algorithm and real-time ambulatory monitoring system for fall detection in elderly people is described. Our system is comprised of accelerometer, tilt sensor and gyroscope. For real-time monitoring, we used Bluetooth. Accelerometer measures kinetic force, tilt sensor and gyroscope estimates body posture. Also, we suggested algorithm using signals which obtained from the system attached to the chest for fall detection. To evaluate our system and algorithm, we experimented on three people aged over 26 years. The experiment of four cases such as forward fall, backward fall, side fall and sit-stand was repeated ten times and the experiment in daily life activity was performed one time to each subject. These experiments showed that our system and algorithm could distinguish between falling and daily life activity. Moreover, the accuracy of fall detection is 96.7%. Our system is especially adapted for long-time and real-time ambulatory monitoring of elderly people in emergency situation.
NASA Technical Reports Server (NTRS)
1972-01-01
A general graded life detection approach ranging from environmental and in situ observations to specific metabolic experiments on Mars is reported. A zero dead volume leak and computer mediated data acquisition system is also discussed. Soil analyses were also conducted.
A search for life on earth at 100 meter resolution
NASA Technical Reports Server (NTRS)
Sagan, C.; Wallace, D.
1970-01-01
A study of several thousand photos indicated approximately 1% of Gemini and Apollo photographs of the earth at 100 m resolution revealed signs of life; rectangular arrays due to human agricultural and urban territoriality, roads, canals, jet contrails, and industrial pollution. Potential false positives such as dunes, sand bars, and jet stream clouds abound. A curve was derived for the detectivity of contemporary life on earth, in a plot of ground resolution versus global coverage. A comparable biology on Mars would not have been detected by all observations of Mars through Mariner 7. Forthcoming Mars orbiter and lander imaging experiments hold significant promise of detecting life on Mars of contemporary terrestrial extent and advancement, should such life exist.
Refinement of planetary protection policy for Mars missions
NASA Technical Reports Server (NTRS)
DeVincenzi, D. L.; Stabekis, P.; Barengoltz, J.
1996-01-01
Under existing COSPAR policy adopted in 1984, missions to Mars (landers, probes, and some orbiters) are designated as Category IV missions. As such, the procedures for implementing planetary protection requirements could include trajectory biasing, cleanrooms, bioload reduction, sterilization of hardware, and bioshields. In 1992, a U.S. National Research Council study recommended that controls on forward contamination of Mars be tied to specific mission objectives. The report recommended that Mars landers with life detection instruments be subject to at least Viking-level sterilization procedures for bioload reduction, while spacecraft (including orbiters) without life detection instruments be subject to at least Viking-level pre-sterilization procedures for bioload reduction but need not be sterilized. In light of this, it is proposed that the current policy's Category IV and its planetary protection requirements be divided into two sub-categories as follows: Category IVa, for missions comprising landers and probes without life detection experiments, which will meet a specified bioburden limit for exposed surfaces, and Category IVb, for landers and probes with life detection experiments, which will require sterilization of landed systems. In addition, Category III orbiter mission specifications are expanded to be consistent with these recommendations.
NASA Astrophysics Data System (ADS)
Stoker, C. R.
2007-07-01
Drilling for subsurface life should be a goal of future Mars missions. The approach is illustrated by MARTE: A search for subsurface life in Rio Tinto, Spain explored a biosphere using reduced iron and sulfur minerals and demonstrated automated drilling, sample handling, and life detection.
NASA Technical Reports Server (NTRS)
1975-01-01
The Viking program, its characteristics, goals, and investigations are described. The program consists of launching two spacecraft to Mars in 1975 to soft-land on the surface and test for signs of life. Topics discussed include the launch, the journey through space, tracking, Mars orbit and landing, experiments on the search for life, imaging systems, lander camera, water detection experiments, thermal mapping, and a possible weather station on Mars.
Automated Microbial Metabolism Laboratory
NASA Technical Reports Server (NTRS)
1971-01-01
The effect of several environmental parameters on previously developed life detection systems is explored. Initial attempts were made to conduct all the experiments in a moist mode (high soil volume to water volume ratio). However, only labeled release and measurement of ATP were found to be feasible under conditions of low moisture. Therefore, these two life detection experiments were used for most of the environmental effects studies. Three soils, Mojave (California desert), Wyaconda (Maryland, sandy loam) and Victoria Valley (Antarctic desert) were generally used throughout. The environmental conditions studied included: incubation temperature 3 C to 80 C, ultraviolet irradiation of soils, variations in soil/liquid ratio, specific atmospheric gases, various antimetabolites, specific substrates, and variation in pH. An experiment designed to monitor nitrogen metabolism was also investigated.
Practical life log video indexing based on content and context
NASA Astrophysics Data System (ADS)
Tancharoen, Datchakorn; Yamasaki, Toshihiko; Aizawa, Kiyoharu
2006-01-01
Today, multimedia information has gained an important role in daily life and people can use imaging devices to capture their visual experiences. In this paper, we present our personal Life Log system to record personal experiences in form of wearable video and environmental data; in addition, an efficient retrieval system is demonstrated to recall the desirable media. We summarize the practical video indexing techniques based on Life Log content and context to detect talking scenes by using audio/visual cues and semantic key frames from GPS data. Voice annotation is also demonstrated as a practical indexing method. Moreover, we apply body media sensors to record continuous life style and use body media data to index the semantic key frames. In the experiments, we demonstrated various video indexing results which provided their semantic contents and showed Life Log visualizations to examine personal life effectively.
[Design and experiment of micro biochemical detector based on micro spectrometer].
Yu, Qing-hua; Wen, Zhi-yu; Chen, Gang; Dai, Wei-wei; Liu, Nian-ci; Wu, Xin
2012-03-01
According to the requirements of rapid detection of important life parameters for the sick and wounded, a new micro bio-chemical detection configuration was proposed utilizing continuous spectroscopy analysis, which was founded on MOEMS and embedded technology. The configuration was developed as so much research work was carried out on the detecting objects and methods. Important parameters such as stray light, absorbance linearity, absorbance ratability, stability and temperature accuracy of the instrument were tested, which are all in good agreement with the design requirements. Clinic tests show that it can detect multiple life parameters quickly (Na+, GLU, Hb eg.).
Detection of soil microorganism in situ by combined gas chromatography mass spectrometry
NASA Technical Reports Server (NTRS)
Alexander, M.; Duxbury, J. M.; Francis, A. J.; Adamson, J.
1972-01-01
Experimental tests were made to determine whether analysis of volatile metabolic products, formed in situ, is a viable procedure for an extraterrestrial life detection system. Laboratory experiments, carried out under anaerobic conditions with addition of carbon source, extended to include a variety of soils and additional substrates. In situ experiments were conducted without amendment using a vacuum sampling system.
Ames Coronagraph Experiment: Enabling Missions to Directly Image Exoplanets
NASA Technical Reports Server (NTRS)
Belikov, Ruslan
2014-01-01
Technology to find biomarkers and life on other worlds is rapidly maturing. If there is a habitable planet around the nearest star, we may be able to detect it this decade with a small satellite mission. In the 2030 decade, we will likely know if there is life in our Galactic neighborhood (1000 nearest stars). The Ames Coronagraph Experiment is developing coronagraphic technologies to enable such missions.
A search for a nonbiological explanation of the Viking Labeled Release life detection experiment
NASA Technical Reports Server (NTRS)
Levin, G. V.; Straat, P. A.
1981-01-01
The possibility of nonbiological reactions involving hydrogen peroxide being the source of the positive response detected by the Viking Labeled Release (LR) life detection experiment on the surface of Mars is assessed. Labeled release experiments were conducted in the LR Test Standards Module which replicates the Viking flight instrument configuration on analog Martian soils prepared to match the Viking inorganic analysis of Mars surface material to which an aqueous solution of hydrogen peroxide had been added. Getter experiments were also conducted to compare several reactions simultaneously in the presence and absence of UV radiation prior to the addition of nutrient. Hydrogen peroxide on certain analog soils is found to be capable of reproducing the kinetics and thermal information contained in the Mars data. The peroxide concentration necessary for this response, however, is shown to require a chemical stability or production rate much greater than seems likely in the Mars environment. As previous experiments have shown hydrogen peroxide to be the most likely nonbiological source of the positive LR response, it is concluded that the presence of a biological agent on Mars must not yet be ruled out.
NASA Astrophysics Data System (ADS)
Meinert, C.; Jones, N. C.; Hoffmann, S. V.; Nahon, L.; d'Hendecourt, L.; Meierhenrich, U. J.
2017-07-01
Simulated cometary ice experiments have indicated that circularly polarised light could be the initial source of life's handedness. We detected chiral sugars, amino acids and their molecular precursors within these interstellar achiral ice analogues.
Matsubara, Hiroki; Enami, Miki; Hirose, Keiko; Kamikura, Takahisa; Nishi, Taiki; Takei, Yutaka; Inaba, Hideo
2015-04-01
To determine the effect of Japanese obligatory basic life support training for new driver's license applicants on their willingness to carry out basic life support. We distributed a questionnaire to 9,807 participants of basic life support courses in authorized driving schools from May 2007 to April 2008 after the release of the 2006 Japanese guidelines. The questionnaire explored the participants' willingness to perform basic life support in four hypothetical scenarios: cardiopulmonary resuscitation on one's own initiative; compression-only cardiopulmonary resuscitation following telephone cardiopulmonary resuscitation; early emergency call; and use of an automated external defibrillator. The questionnaire was given at the beginning of the basic life support course in the first 6-month term and at the end in the second 6-month term. The 9,011 fully completed answer sheets were analyzed. The training significantly increased the proportion of respondents willing to use an automated external defibrillator and to perform cardiopulmonary resuscitation on their own initiative in those with and without prior basic life support training experience. It significantly increased the proportion of respondents willing to carry out favorable actions in all four scenarios. In multiple logistic regression analysis, basic life support training and prior training experiences within 3 years were associated with the attitude. The analysis of reasons for unwillingness suggested that the training reduced the lack of confidence in their skill but did not attenuate the lack of confidence in detection of arrest or clinical judgment to initiate a basic life support action. Obligatory basic life support training should be carried out periodically and modified to ensure that participants gain confidence in judging and detecting cardiac arrest.
Searching for Extant Life on Mars - The ATP-Firefly LuciferinLuciferase Technique
NASA Astrophysics Data System (ADS)
Obousy, R. K.; Tziolas, A. C.; Kaltsas, K.; Sims, M. R.; Grant, W. D.
We have investigated the use of the ATP-Firefly Luciferin/Luciferase (FFL) enzymic photoluminescent reaction as a possible means of detecting extant life in the Martian environment. Experiments carried out by the authors illustrate the capacity of the method to successfully detect extant forms of life on Mars assuming ATP is an intrinsic part of the biochemistry of such life-forms. A photodiode based apparatus, built to test the assumptions and applicability of the ATP-Firefly Luciferase/Luciferin technique to an exobiologically inclined mission to Mars, revealed the adequate resolution and reproducibility of the methodology plus areas of improvement. Also detailed are extraction, delivery and analysis system concepts, proposed for future Mars missions.
Revision to Planetary Protection Policy for Mars Missions
NASA Technical Reports Server (NTRS)
DeVincenzi, D. L.; Stabekis, P.; Barengoltz, J.; Morrison, David (Technical Monitor)
1994-01-01
Under existing COSPAR policy adopted in 1984, missions to Mars (landers, probes, and some orbiters) are designated as Category IV missions. As such, the procedures for implementing planetary protection requirements could include trajectory biasing, cleanrooms, bioload reduction, sterilization of hardware, and bioshields, i. e. requirements could be similar to Viking. However, in 1992, a U. S. National Academy of Sciences study recommended that controls on forward contamination of Mars be tied to specific mission objectives. The report recommended that Mars landers with life detection instruments be subject to at least Viking-level sterilization procedures for bioload reduction, while spacecraft (including orbiters) without life detection instruments be subject to at least Viking-level pre sterilization procedures for bioload reduction but need not be sterilized. In light of this, it is proposed that the current policy's Category IV missions and their planetary protection requirements be divided into two subcategories as follows: Category IV A, for missions comprising landers and probes without life detection experiments and some orbiters, which will meet a specified bioburden limit for exposed surfaces; Category IV B, for landers and probes with life detection experiments, which will require complete system sterilization. For Category IV A missions, bioburden specifications will be proposed and implementing procedures discussed. A resolution will be proposed to modify the existing COSPAR policy to reflect these changes. Similar specifications, procedures, and resolution for Category IV B missions will be the subject of a later study.
Viking and Mars Rover exobiology
NASA Technical Reports Server (NTRS)
Schwartz, D. E.; Mancinelli, Rocco L.; Ohara, B. J.
1989-01-01
Other than Earth, Mars is the planet generating the greatest interest among those researching and contemplating the origin and distribution of life throughout the universe. The similarity of the early environments of Earth and Mars, and the biological evolution on early Earth provides the motivation to seriously consider the possibility of a primordial Martian biosphere. In 1975 the Viking project launched two unmanned spacecraft to Mars with the intent of finding evidence of the existence of present or past life on this planet. Three Viking Biology experiments were employed: the Labeled Release experiment, the Gas Exchange Experiment, and the Pyrolytic Release experiment. Each of these three experiments tested for microbial existence and utilization of a substrate by examining the gases evolved from specific chemical reactions. Although the results of these experiments were inconclusive, they inferred that there are no traces of extant life on Mars. However, the experiments did not specifically look for indication of extinct life. Therefore, most of the exobiologic strategies and experiments suggested for the Mars Rover Sample Return Mission involve searching for signature of extinct life. The most significant biological signatures and chemical traces to detect include: isotopic and chemical signatures of metabolic activity, anomalous concentrations of certain metals, trace and microfossils, organically preserved materials, carbonates, nitrates, and evaporites.
Panel summary of recommendations
NASA Technical Reports Server (NTRS)
Dunbar, Bonnie J.; Coleman, Martin E.; Mitchell, Kenneth L.
1990-01-01
The following Space Station internal contamination topics were addressed: past flight experience (Skylab and Spacelab missions); present flight activities (Spacelabs and Soviet Space Station Mir); future activities (materials science and life science experiments); Space Station capabilities (PPMS, FMS, ECLSS, and U.S. Laboratory overview); manned systems/crew safety; internal contamination detection; contamination control - stowage and handling; and contamination control - waste gas processing. Space Station design assumptions are discussed. Issues and concerns are discussed as they relate to (1) policy and management, (2) subsystem design, (3) experiment design, and (4) internal contamination detection and control. The recommendations generated are summarized.
The Gas Exchange Experiment for life detection - The Viking Mars Lander.
NASA Technical Reports Server (NTRS)
Oyama, V. I.
1972-01-01
The Gas Exchange Experiment of the Viking mission accepts a sample of Martian soil, incubates this soil with nutrient medium, and periodically samples the enclosed atmosphere over this soil for the gases H2, N2, O2, Kr, and CO2. These gases are analyzed by an automated gas chromatograph, and the data are transmitted to earth. The design of the experiment and the qualitative and quantitative changes, if any, of gas composition should allow conclusions to be made on the presence of life on Mars. Data and theory substantiating this approach are presented.
NASA Technical Reports Server (NTRS)
2004-01-01
A revolutionary, low-calorie sugar is now available to the food and beverage market, offering an all-natural alternative to table sugar and artificial sweeteners. Tagatose, a sugar that appears in nature in small quantities, began its unusual journey to the commercial market nearly 30 years ago, when Dr. Gilbert V. Levin invented a life detection experiment to place aboard NASA s Mars Viking 1 and Viking 2 landers. The experiment involved using radiation-laced nutrients to determine the presence of microbial life in Martian soil samples.
Post-harvest decay in fresh-cut lettuce
USDA-ARS?s Scientific Manuscript database
Shelf-life of fresh-cut lettuce was assessed in two mapping population (Salinas 88 x La Brillante, and Pavane x Parade. The most significant QTL was detected in both populations on linkage group 4. This QTL was detected in seven experiments grown in different environments. Molecular markers are bein...
Microbial fuel cells applied to the metabolically based detection of extraterrestrial life.
Abrevaya, Ximena C; Mauas, Pablo J D; Cortón, Eduardo
2010-12-01
Since the 1970s, when the Viking spacecrafts carried out experiments to detect microbial metabolism on the surface of Mars, the search for nonspecific methods to detect life in situ has been one of the goals of astrobiology. It is usually required that a methodology detect life independently from its composition or form and that the chosen biological signature point to a feature common to all living systems, such as the presence of metabolism. In this paper, we evaluate the use of microbial fuel cells (MFCs) for the detection of microbial life in situ. MFCs are electrochemical devices originally developed as power electrical sources and can be described as fuel cells in which the anode is submerged in a medium that contains microorganisms. These microorganisms, as part of their metabolic process, oxidize organic material, releasing electrons that contribute to the electric current, which is therefore proportional to metabolic and other redox processes. We show that power and current density values measured in MFCs that use microorganism cultures or soil samples in the anode are much larger than those obtained with a medium free of microorganisms or sterilized soil samples, respectively. In particular, we found that this is true for extremophiles, which have been proposed as potential inhabitants of extraterrestrial environments. Therefore, our results show that MFCs have the potential to be used for in situ detection of microbial life.
Microbial Fuel Cells Applied to the Metabolically Based Detection of Extraterrestrial Life
NASA Astrophysics Data System (ADS)
Abrevaya, Ximena C.; Mauas, Pablo J. D.; Cortón, Eduardo
2010-12-01
Since the 1970s, when the Viking spacecrafts carried out experiments to detect microbial metabolism on the surface of Mars, the search for nonspecific methods to detect life in situ has been one of the goals of astrobiology. It is usually required that a methodology detect life independently from its composition or form and that the chosen biological signature point to a feature common to all living systems, such as the presence of metabolism. In this paper, we evaluate the use of microbial fuel cells (MFCs) for the detection of microbial life in situ. MFCs are electrochemical devices originally developed as power electrical sources and can be described as fuel cells in which the anode is submerged in a medium that contains microorganisms. These microorganisms, as part of their metabolic process, oxidize organic material, releasing electrons that contribute to the electric current, which is therefore proportional to metabolic and other redox processes. We show that power and current density values measured in MFCs that use microorganism cultures or soil samples in the anode are much larger than those obtained with a medium free of microorganisms or sterilized soil samples, respectively. In particular, we found that this is true for extremophiles, which have been proposed as potential inhabitants of extraterrestrial environments. Therefore, our results show that MFCs have the potential to be used for in situ detection of microbial life.
Possibilities for the detection of hydrogen peroxide-water-based life on Mars by the Phoenix Lander
NASA Astrophysics Data System (ADS)
Houtkooper, Joop M.; Schulze-Makuch, Dirk
2009-04-01
The Phoenix Lander landed on Mars on 25 May 2008. It has instruments on board to explore the geology and climate of subpolar Mars and to explore if life ever arose on Mars. Although the Phoenix mission is not a life detection mission per se, it will look for the presence of organic compounds and other evidence to support or discredit the notion of past or present life. The possibility of extant life on Mars has been raised by a reinterpretation of the Viking biology experiments [Houtkooper, J. M., Schulze-Makuch, D., 2007. A possible biogenic origin for hydrogen peroxide on Mars: the Viking results reinterpreted. International Journal of Astrobiology 6, 147-152]. The results of these experiments are in accordance with life based on a mixture of water and hydrogen peroxide instead of water. The near-surface conditions on Mars would give an evolutionary advantage to organisms employing a mixture of H 2O 2 and H 2O in their intracellular fluid: the mixture has a low freezing point, is hygroscopic and provides a source of oxygen. The H 2O 2-H 2O hypothesis also explains the Viking results in a logically consistent way. With regard to its compatibility with cellular contents, H 2O 2 is used for a variety of purposes in terran biochemistry. The ability of the anticipated organisms to withstand low temperatures and the relatively high water vapor content of the atmosphere in the Martian arctic, means that Phoenix will land in an area not inimical to H 2O 2-H 2O-based life. Phoenix has a suite of instruments which may be able to detect the signatures of such putative organisms.
Acetate: A better astrobiological indicator of life than methane?
NASA Astrophysics Data System (ADS)
Kanik, I.; Russell, M. J.; Hodyss, R. P.; Johnson, P. V.
2009-12-01
The emergence of life on the ocean floor of the early Earth has implications for life detection on other rocky planetary bodies having subsurface ocean or ground waters in our solar system. At bottom life hydrogenates carbon dioxide. This is true not only of oxygenic photosynthesis—a relatively late evolutionary invention—but also of autotrophic chemosynthesizers such as the acetogenic bacteria and the methanoarchaea; respectively probably the first and second organisms to have emerged on Earth. Both of these prokaryotes use the acetyl coenzyme-a pathway for biosynthesis, though the variant leading to methanogenesis is substantially more complicated and therefore more highly evolved. Yet serpentinization and volcanism can produce methane with facility—an ambiguity that confounds life detection. In contrast, hydrothermal vent experiments to date along with hot spring analyses have indicated that no significant concentrations of abiotic acetate were produced in spite of the simplicity of the biological pathway. It seems that the geochemical conditions that generate abiotic methane are generally too reducing to produce acetate. Thus, the generation of acetate is solely a biotic process. As there is every reason to believe that the same chemical and electrochemical tensions would occur on other wet rocky planets containing subsurface ocean or ground waters. This encourages us to look into chemical and spectroscopic methods of detecting of acetate (both remotely and in situ) which is a better indicator than methane for the past or present biological activity on planetary bodies such as Mars. We, at the Jet Propulsion Laboratory, have designed laboratory experiments to investigate the feasibility of detecting acetate using conventional chemical and spectroscopic methods. The results and applicability of these techniques for the future astrobiology missions will be discussed.
Analysis of methods for growth detection in the search for extraterrestrial life.
Merek, E L; Oyama, V I
1968-05-01
In the search for life on other planets, experiments designed to detect the growth of microorganisms may prove to be definitive when coupled with chemical characterization and metabolic experiments. If organisms are not abundant, growth provides the only means for obtaining a large mass of biological material suitable for chemical compositional analyses and metabolic assays. Several methods of monitoring growth are described. Of these, optical monitoring in a unique system free of soil particles is advanced as the most appropriate. Theoretical problems related to the formulation of culture media are discussed, and several possible solutions are proposed. The sampling system, the type of monitoring, the size and placement of inoculum, and the medium volume and composition are contingent upon one another and must be integrated without sacrifice to the biological demands.
NASA Astrophysics Data System (ADS)
Khanmohammadi, Hamid; Rezaeian, Khatereh; Abdollahi, Alieh
2015-03-01
New N-monosubstituted diaminomaleonitrile-based azo-azomethine dyes have been synthesized in order to develop colorimetric sensors for detection of biologically important anions in aqueous media. Importantly, the reported sensor decorated with strong electron-withdrawing group can detect inorganic fluoride in water even at 0.037 ppm level, which is lower than WHO permissible level (below 1 ppm). Successfully, the prepared dyes were used for qualitative and quantitative detection of inorganic fluoride in toothpaste and mouthwash. The anion recognition mechanism was also investigated by detailed UV-Vis and 1H NMR experiments. The detailed 1H NMR experiments corroborated that anion recognition is based on the deprotonation phenomenon.
Autonomous detection of ISO fade point with color laser printers
NASA Astrophysics Data System (ADS)
Yan, Ni; Maggard, Eric; Fothergill, Roberta; Jessome, Renee J.; Allebach, Jan P.
2015-01-01
Image quality assessment is a very important field in image processing. Human observation is slow and subjective, it also requires strict environment setup for the psychological test 1. Thus developing algorithms to match desired human experiments is always in need. Many studies have focused on detecting the fading phenomenon after the materials are printed, that is to monitor the persistence of the color ink 2-4. However, fading is also a common artifact produced by printing systems when the cartridges run low. We want to develop an automatic system to monitor cartridge life and report fading defects when they appear. In this paper, we first describe a psychological experiment that studies the human perspective on printed fading pages. Then we propose an algorithm based on Color Space Projection and K-means clustering to predict the visibility of fading defects. At last, we integrate the psychological experiment result with our algorithm to give a machine learning tool that monitors cartridge life.
Design and experiment of a neural signal detection using a FES driving system.
Zonghao, Huang; Zhigong, Wang; Xiaoying, Lu; Wenyuan, Li; Xiaoyan, Shen; Xintai, Zhao; Shushan, Xie; Haixian, Pan; Cunliang, Zhu
2010-01-01
The channel bridging, signal regenerating, and functional rebuilding of injured nerves is one of the most important issues in life science research. In recent years, some progresses in the research area have been made in repairing injured nerves with microelectronic neural bridge. Based on the previous work, this paper presents a neural signal detection and functional electrical stimulation (FES) driving system with using high performance operational amplifiers, which has been realized. The experimental results show that the designed system meets requirements. In animal experiments, sciatic nerve signal detection, regeneration and function rebuilding between two toads have been accomplished successfully by using the designed system.
2004-01-01
This volume contains selected papers of the Joint COSPAR-IAC event "Search for signatures of life in the solar system, terrestrial analogues and simulation experiments" held during the World Space Congress 2002 in Houston, Texas, USA. The first section of the volume reports on the rich variety of terrestrial microbial communities adapted to extreme environments, such as microbial life at very low temperatures in permafrost and ice layers, at high salt concentrations, as inhabitants of rocks and the microbial recolonization of impact-shocked rocks. These communities are suggested to serve as analogues for extraterrestrial habitats, which are also described in this section. The second section deals with the detection of biomarkers and signatures from extinct life on Earth, which might provide clues for detection of potential extraterrestrial biomarkers. This section is followed by reports of experiments in space and in the laboratory simulating space conditions, such as the prebiotic organic chemistry, the chemistry of dust particles to be detected during the Cassini mission to Saturn, as well as the photochemistry of biological systems exposed to space or planetary surface conditions. The second part of the issue contains papers from the session "The nervous system: space flight environmental factors effects--present results and new perspectives." The presentations in this session explored various aspects of the effects of exposure to protons and heavy particles on central nervous system function and on behavior. The second series of papers examines the effects of exposure to heavy particles and protons on neurochemistry and on behavior.
NASA Technical Reports Server (NTRS)
Fujishima, Kosuke; Dziomba, Szymon; Takahagi, Wataru; Shibuya, Takazo; Takano, Yoshinori; Guerrouache, Mohamed; Carbonnier, Benjamin; Takai, Ken; Rothschild, Lynn J.; Yano, Hajime
2016-01-01
In situ detection of organic molecules in the extraterrestrial environment provides a key step towards better understanding the variety and the distribution of building blocks of life and it may ultimately lead to finding extraterrestrial life within the Solar System. Here we present combined results of two separate experiments that enable us to realize such in situ life signature detection from the deep habitats of the "Ocean World": a hydrothermal reactor experiment simulating complex organic synthesis and a simulated fly-through capture experiment of organic-bearing microparticles using silica aerogels, followed by subsequent analysis. Both experiments employ peptide as a plausible organics existing in Encleadus plume particles produced in its subsurface ocean. Recent laboratory hydrothermal experiments and a theoretical model on silica saturation indicated an on going hydrothermal reactions in subsurface Enceladus ocean. Given the porous chondritic origin of the core, it is likely that organic compounds originated by radiation chemistry such as amino acid precursors could have been provided, leached, and altered through widespread water-rock interactions. By using the same laboratory experimental setup from the latest water-rock interaction study, we performed amino acid polymerization experiments for 144 days and monitored the organic complexity changing over time. So far over 3,000 peaks up to the size of greater than 600 MW were observed through the analysis of capillary electrophoresis time-of-flight mass spectrometry (CE-TOF-MS) with an indication of amino acid derivatives and short peptides. Generally abiotic polymerization of enantiomeric amino acids results in forming stereoisomeric peptides with identical molecular weight and formula as opposed to homochiral biopolymers. Assuming Enceladus plume particles may contain a mixture of stereoisomeric peptides, we were able to distinguish 16 of the 17 stereoisomeric tripeptides as a test sample using capillary electrophoresis (CE) under optimized conditions. We further conducted Enceladus plume fly-through capture experiment by accelerating peptides soaked in rock particles up to a speed of 5.7 km/s and capturing with originally developed hydrophobic silica aerogels. Direct peptide extraction with acetonitrile-water followed by CE analysis led to detection of only but two stereoisomeric acidic peptide peaks, presenting the first run-through hypervelocuty impact sample analysis targeting peptides as key molecule to to understand the ongoing astrobiology on Enceladus.
Optical Detection of Organic Chemical Biosignatures at Hydrothermal Vents
NASA Technical Reports Server (NTRS)
Conrad, P. G.; Lane, A. L.; Bhartia, R.; Hug, W. H.
2004-01-01
We have developed a non-contact, optical life detection instrument that can detect organic chemical biosignatures in a number of different environments, including dry land, shallow aqueous, deep marine or in ice. Hence, the instrument is appropriate as a biosignature survey tool both for Mars exploration or in situ experiments in an ice-covered ocean such as one might wish to explore on Europa. Here, we report the results we obtained on an expedition aboard the Russian oceanographic vessel Akademik Mstislav Keldysh to hydrothermal vent sites in the Pacific Ocean using our life detection instrument MCDUVE, a multichannel, deep ultraviolet excitation fluorescence detector. MCDUVE detected organic material distribution on rocks near the vent, as well as direct detection of organisms, both microbial and microscopic. We also were able to detect organic material issuing directly from vent chimneys, measure the organic signature of the water column as we ascended, and passively observe the emission of light directly from some vents.
Life-table methods for detecting age-risk factor interactions in long-term follow-up studies.
Logue, E E; Wing, S
1986-01-01
Methodological investigation has suggested that age-risk factor interactions should be more evident in age of experience life tables than in follow-up time tables due to the mixing of ages of experience over follow-up time in groups defined by age at initial examination. To illustrate the two approaches, age modification of the effect of total cholesterol on ischemic heart disease mortality in two long-term follow-up studies was investigated. Follow-up time life table analysis of 116 deaths over 20 years in one study was more consistent with a uniform relative risk due to cholesterol, while age of experience life table analysis was more consistent with a monotonic negative age interaction. In a second follow-up study (160 deaths over 24 years), there was no evidence of a monotonic negative age-cholesterol interaction by either method. It was concluded that age-specific life table analysis should be used when age-risk factor interactions are considered, but that both approaches yield almost identical results in absence of age interaction. The identification of the more appropriate life-table analysis should be ultimately guided by the nature of the age or time phenomena of scientific interest.
Beyond Detection: Nuclear Physics with a Webcam in an Educational Setting
ERIC Educational Resources Information Center
Pallone, A.; Barnes, P.
2016-01-01
Basic understanding of nuclear science enhances our daily-life experience in many areas, such as the environment, medicine, electric power generation, and even politics. Yet typical school curricula do not provide for experiments that explore the topic. We present a means by which educators can use the ubiquitous webcam and inexpensive sources of…
Patients understanding of depression associated with chronic physical illness: a qualitative study
2014-01-01
Background Detection of depression can be difficult in primary care, particularly when associated with chronic illness. Patient beliefs may affect detection and subsequent engagement with management. We explored patient beliefs about the nature of depression associated with physical illness. Methods A qualitative interview study of patients registered with general practices in Leeds, UK. We invited patients with coronary heart disease or diabetes from primary care to participate in semi-structured interviews exploring their beliefs and experiences. We analysed transcripts using a thematic approach, extended to consider narratives as important contextual elements. Results We interviewed 26 patients, including 17 with personal experience of depression. We developed six themes: recognising a problem, complex causality, the role of the primary care, responsibility, resilience, and the role of their life story. Participants did not consistently talk about depression as an illness-like disorder. They described a change in their sense of self against the background of their life stories. Participants were unsure about seeking help from general practitioners (GPs) and felt a personal responsibility to overcome depression themselves. Chronic illness, as opposed to other life pressures, was seen as a justifiable cause of depression. Conclusions People with chronic illness do not necessarily regard depression as an easily defined illness, especially outside of the context of their life stories. Efforts to engage patients with chronic illness in the detection and management of depression may need further tailoring to accommodate beliefs about how people view themselves, responsibility and negative views of treatment. PMID:24555886
Nucleic Acid Extraction from Synthetic Mars Analog Soils for in situ Life Detection.
Mojarro, Angel; Ruvkun, Gary; Zuber, Maria T; Carr, Christopher E
2017-08-01
Biological informational polymers such as nucleic acids have the potential to provide unambiguous evidence of life beyond Earth. To this end, we are developing an automated in situ life-detection instrument that integrates nucleic acid extraction and nanopore sequencing: the Search for Extra-Terrestrial Genomes (SETG) instrument. Our goal is to isolate and determine the sequence of nucleic acids from extant or preserved life on Mars, if, for example, there is common ancestry to life on Mars and Earth. As is true of metagenomic analysis of terrestrial environmental samples, the SETG instrument must isolate nucleic acids from crude samples and then determine the DNA sequence of the unknown nucleic acids. Our initial DNA extraction experiments resulted in low to undetectable amounts of DNA due to soil chemistry-dependent soil-DNA interactions, namely adsorption to mineral surfaces, binding to divalent/trivalent cations, destruction by iron redox cycling, and acidic conditions. Subsequently, we developed soil-specific extraction protocols that increase DNA yields through a combination of desalting, utilization of competitive binders, and promotion of anaerobic conditions. Our results suggest that a combination of desalting and utilizing competitive binders may establish a "universal" nucleic acid extraction protocol suitable for analyzing samples from diverse soils on Mars. Key Words: Life-detection instruments-Nucleic acids-Mars-Panspermia. Astrobiology 17, 747-760.
NASA Astrophysics Data System (ADS)
Stoker, Carol R.; Cannon, Howard N.; Dunagan, Stephen E.; Lemke, Lawrence G.; Glass, Brian J.; Miller, David; Gomez-Elvira, Javier; Davis, Kiel; Zavaleta, Jhony; Winterholler, Alois; Roman, Matt; Rodriguez-Manfredi, Jose Antonio; Bonaccorsi, Rosalba; Bell, Mary Sue; Brown, Adrian; Battler, Melissa; Chen, Bin; Cooper, George; Davidson, Mark; Fernández-Remolar, David; Gonzales-Pastor, Eduardo; Heldmann, Jennifer L.; Martínez-Frías, Jesus; Parro, Victor; Prieto-Ballesteros, Olga; Sutter, Brad; Schuerger, Andrew C.; Schutt, John; Rull, Fernando
2008-10-01
The Mars Astrobiology Research and Technology Experiment (MARTE) simulated a robotic drilling mission to search for subsurface life on Mars. The drill site was on Peña de Hierro near the headwaters of the Río Tinto river (southwest Spain), on a deposit that includes massive sulfides and their gossanized remains that resemble some iron and sulfur minerals found on Mars. The mission used a fluidless, 10-axis, autonomous coring drill mounted on a simulated lander. Cores were faced; then instruments collected color wide-angle context images, color microscopic images, visible near infrared point spectra, and (lower resolution) visible-near infrared hyperspectral images. Cores were then stored for further processing or ejected. A borehole inspection system collected panoramic imaging and Raman spectra of borehole walls. Life detection was performed on full cores with an adenosine triphosphate luciferin-luciferase bioluminescence assay and on crushed core sections with SOLID2, an antibody array-based instrument. Two remotely located science teams analyzed the remote sensing data and chose subsample locations. In 30 days of operation, the drill penetrated to 6 m and collected 21 cores. Biosignatures were detected in 12 of 15 samples analyzed by SOLID2. Science teams correctly interpreted the nature of the deposits drilled as compared to the ground truth. This experiment shows that drilling to search for subsurface life on Mars is technically feasible and scientifically rewarding.
Stoker, Carol R; Cannon, Howard N; Dunagan, Stephen E; Lemke, Lawrence G; Glass, Brian J; Miller, David; Gomez-Elvira, Javier; Davis, Kiel; Zavaleta, Jhony; Winterholler, Alois; Roman, Matt; Rodriguez-Manfredi, Jose Antonio; Bonaccorsi, Rosalba; Bell, Mary Sue; Brown, Adrian; Battler, Melissa; Chen, Bin; Cooper, George; Davidson, Mark; Fernández-Remolar, David; Gonzales-Pastor, Eduardo; Heldmann, Jennifer L; Martínez-Frías, Jesus; Parro, Victor; Prieto-Ballesteros, Olga; Sutter, Brad; Schuerger, Andrew C; Schutt, John; Rull, Fernando
2008-10-01
The Mars Astrobiology Research and Technology Experiment (MARTE) simulated a robotic drilling mission to search for subsurface life on Mars. The drill site was on Peña de Hierro near the headwaters of the Río Tinto river (southwest Spain), on a deposit that includes massive sulfides and their gossanized remains that resemble some iron and sulfur minerals found on Mars. The mission used a fluidless, 10-axis, autonomous coring drill mounted on a simulated lander. Cores were faced; then instruments collected color wide-angle context images, color microscopic images, visible-near infrared point spectra, and (lower resolution) visible-near infrared hyperspectral images. Cores were then stored for further processing or ejected. A borehole inspection system collected panoramic imaging and Raman spectra of borehole walls. Life detection was performed on full cores with an adenosine triphosphate luciferin-luciferase bioluminescence assay and on crushed core sections with SOLID2, an antibody array-based instrument. Two remotely located science teams analyzed the remote sensing data and chose subsample locations. In 30 days of operation, the drill penetrated to 6 m and collected 21 cores. Biosignatures were detected in 12 of 15 samples analyzed by SOLID2. Science teams correctly interpreted the nature of the deposits drilled as compared to the ground truth. This experiment shows that drilling to search for subsurface life on Mars is technically feasible and scientifically rewarding.
Astrobiology's Central Dilemma: How can we detect Life if we cannot even Define it?
NASA Astrophysics Data System (ADS)
Clark, B. C.
2001-11-01
Culling and consolidating from a collection of 102 attributes asserted as properties of Life, and the numerous Definitions of Life which invoke them, a new definition is proposed. Analysis of the pathways to proving that any given entity, from micro-sample to planetary object, harbors one or more lifeforms provides strategies for the observations, experiments and detection approaches. These are necessarily varied because of the relative accessibility/inaccessibility of the samples themselves, for example, from Mars, Europa, the ancient Earth or extra-solar system planets. A two-tiered Definition of Life has been formulated, involving both Lifeform and Organism. Devising exploration strategies with a reasonable probability of success and acceptance should proceed along the steps needed for detection and verification of the minimal properties which define Life itself. Multiple approaches, such as high resolution remote spectroscopy for detection of biomarker gases, in situ demonstrations of energy utilization to performs functions such as anabolic or catabolic transformations, achievement of demonstrated reproduction through multi-condition incubations, and probes for macromolecular biochemicals which indicate information storage should be undertaken wherever possible, as should return of samples to terrestrial laboratories for more versatile, more sensitive and more definitive examinations. Use of control samples is paramount, as is detailed understanding of the chemistry and physics of the environment which constrains the activities and tracers being sought.
Farar, Johannes; Schüssler, Gerhard
2011-01-01
Do some life story patterns exist, which are associated with depression? Can some life story factors be identified, which influence or determine a special kind of personality, predisposing to depression? Retrospective, cross sectional study with nonexperimental character, using a number of 60 nonmelancholic depressed patients. First, they were asked to give an interview on their life story. Then, they were asked to fill in questionnaires about personality, parental style of raising, clinical symptoms and personality disorders. Significant correlations could be found between parental style of raising, a family history affected by depression, a dysfunctional household, the family composition, negative school experience and all investigated styles of personality. Further, clusters of personality, clusters of parental style of raising and clusters of specific life story factors could be detected. Results show a strong relation between life story factors and personality styles, predisposing to depression and emphasize the importance of considering personality, when exploring special life story factors. Vice versa, actual personality styles can point to different patterns of life story and thus, show the relevance for the diagnostic and therapeutic process.
Statistical evaluation of vibration analysis techniques
NASA Technical Reports Server (NTRS)
Milner, G. Martin; Miller, Patrice S.
1987-01-01
An evaluation methodology is presented for a selection of candidate vibration analysis techniques applicable to machinery representative of the environmental control and life support system of advanced spacecraft; illustrative results are given. Attention is given to the statistical analysis of small sample experiments, the quantification of detection performance for diverse techniques through the computation of probability of detection versus probability of false alarm, and the quantification of diagnostic performance.
Detection of Extraterrestrial Ecology (Exoecology)
NASA Technical Reports Server (NTRS)
Jones, Harry; DeVincenzi, Donald L. (Technical Monitor)
2000-01-01
Researchers in the Astrobiology Technology Branch at Ames Research Center have begun investigating alternate concepts for the detection of extraterrestrial life. We suggest searching for extraterrestrial ecology, exoecology, as well as for extraterrestrial biology, exobiology. Ecology describes the interactions of living things with their environment. All ecosystems are highly constrained by their environment and are constrained by well-known system design principles. Ecology could exist wherever there is an energy source and living I things have discovered some means to capture, store, and use the available energy. Terrestrial ecosystems use as energy sources, light, organic molecules, and in thermal vents and elsewhere, simple inorganic molecules. Ecosystem behavior is controlled by matter and energy conservation laws and can be described by linear and nonlinear dynamic systems theory. Typically in an ecosystem different molecules are not in chemical equilibrium and scarce material is conserved, stored, or recycled. Temporal cycles and spatial variations are often observed. These and other -eneral principles of exoecology can help guide the search for extraterrestrial life. The chemical structure observed in terrestrial biology may be highly contingent on evolutionary accidents. Oxygen was not always abundant on Earth. Primitive sulfur bacteria use hydrogen sulfide and sulfur to perform photosynthesis instead of water and oxygen. Astrobiologists have assumed, for the sake of narrowing and focusing our life detection strategies, that extraterrestrial life will have detailed chemical similarities with terrestrial life. Such assumptions appear very reasonable and they allow us to design specific and highly sensitive life detection experiments. But the fewer assumptions we make, the less chance we have of being entirely wrong The best strategy for the detection of extraterrestrial life could be a mixed strategy. We should use detailed assumptions based on terrestrial biology to guide some but not all future searches for alien life. The systems principles of exoecology seem much more fundamental and inescapable than the terrestrial biology analogies of exobiology. We should search for exoecology as well as exobiology.
Measuring double-electron capture with liquid xenon experiments
NASA Astrophysics Data System (ADS)
Mei, D.-M.; Marshall, I.; Wei, W.-Z.; Zhang, C.
2014-01-01
We investigate the possibilities of observing the decay mode for 124Xe in which two electrons are captured, two neutrinos are emitted, and the final daughter nucleus is in its ground state, using dark matter experiments with liquid xenon. The first upper limit of the decay half-life is calculated to be 1.66 × 1021 years at a 90% confidence level (C.L.) obtained with the published background data from the XENON100 experiment. Employing a known background model from the large underground xenon (LUX) experiment, we predict that the detection of double-electron capture of 124Xe to the ground state of 124Te with LUX will have approximately 115 events, assuming a half-life of 2.9 × 1021 years. We conclude that measuring 124Xe 2ν double-electron capture to the ground state of 124Te can be performed more precisely with the proposed LUX-Zeplin (LZ) experiment.
High precision measurements of 26Naβ- decay
NASA Astrophysics Data System (ADS)
Grinyer, G. F.; Svensson, C. E.; Andreoiu, C.; Andreyev, A. N.; Austin, R. A.; Ball, G. C.; Chakrawarthy, R. S.; Finlay, P.; Garrett, P. E.; Hackman, G.; Hardy, J. C.; Hyland, B.; Iacob, V. E.; Koopmans, K. A.; Kulp, W. D.; Leslie, J. R.; MacDonald, J. A.; Morton, A. C.; Ormand, W. E.; Osborne, C. J.; Pearson, C. J.; Phillips, A. A.; Sarazin, F.; Schumaker, M. A.; Scraggs, H. C.; Schwarzenberg, J.; Smith, M. B.; Valiente-Dobón, J. J.; Waddington, J. C.; Wood, J. L.; Zganjar, E. F.
2005-04-01
High-precision measurements of the half-life and β-branching ratios for the β- decay of 26Na to 26Mg have been measured in β-counting and γ-decay experiments, respectively. A 4π proportional counter and fast tape transport system were employed for the half-life measurement, whereas the γ rays emitted by the daughter nucleus 26Mg were detected with the 8π γ-ray spectrometer, both located at TRIUMF's isotope separator and accelerator radioactive beam facility. The half-life of 26Na was determined to be T1/2=1.07128±0.00013±0.00021s, where the first error is statistical and the second systematic. The logft values derived from these experiments are compared with theoretical values from a full sd-shell model calculation.
Alsina-Pagès, Rosa Ma; Navarro, Joan; Alías, Francesc; Hervás, Marcos
2017-04-13
The consistent growth in human life expectancy during the recent years has driven governments and private organizations to increase the efforts in caring for the eldest segment of the population. These institutions have built hospitals and retirement homes that have been rapidly overfilled, making their associated maintenance and operating costs prohibitive. The latest advances in technology and communications envisage new ways to monitor those people with special needs at their own home, increasing their quality of life in a cost-affordable way. The purpose of this paper is to present an Ambient Assisted Living (AAL) platform able to analyze, identify, and detect specific acoustic events happening in daily life environments, which enables the medic staff to remotely track the status of every patient in real-time. Additionally, this tele-care proposal is validated through a proof-of-concept experiment that takes benefit of the capabilities of the NVIDIA Graphical Processing Unit running on a Jetson TK1 board to locally detect acoustic events. Conducted experiments demonstrate the feasibility of this approach by reaching an overall accuracy of 82% when identifying a set of 14 indoor environment events related to the domestic surveillance and patients' behaviour monitoring field. Obtained results encourage practitioners to keep working in this direction, and enable health care providers to remotely track the status of their patients in real-time with non-invasive methods.
Alsina-Pagès, Rosa Ma; Navarro, Joan; Alías, Francesc; Hervás, Marcos
2017-01-01
The consistent growth in human life expectancy during the recent years has driven governments and private organizations to increase the efforts in caring for the eldest segment of the population. These institutions have built hospitals and retirement homes that have been rapidly overfilled, making their associated maintenance and operating costs prohibitive. The latest advances in technology and communications envisage new ways to monitor those people with special needs at their own home, increasing their quality of life in a cost-affordable way. The purpose of this paper is to present an Ambient Assisted Living (AAL) platform able to analyze, identify, and detect specific acoustic events happening in daily life environments, which enables the medic staff to remotely track the status of every patient in real-time. Additionally, this tele-care proposal is validated through a proof-of-concept experiment that takes benefit of the capabilities of the NVIDIA Graphical Processing Unit running on a Jetson TK1 board to locally detect acoustic events. Conducted experiments demonstrate the feasibility of this approach by reaching an overall accuracy of 82% when identifying a set of 14 indoor environment events related to the domestic surveillance and patients’ behaviour monitoring field. Obtained results encourage practitioners to keep working in this direction, and enable health care providers to remotely track the status of their patients in real-time with non-invasive methods. PMID:28406459
Sulfate Minerals: A Problem for the Detection of Organic Compounds on Mars?
Watson, Jonathan S.; Najorka, Jens; Luong, Duy; Sephton, Mark A.
2015-01-01
Abstract The search for in situ organic matter on Mars involves encounters with minerals and requires an understanding of their influence on lander and rover experiments. Inorganic host materials can be helpful by aiding the preservation of organic compounds or unhelpful by causing the destruction of organic matter during thermal extraction steps. Perchlorates are recognized as confounding minerals for thermal degradation studies. On heating, perchlorates can decompose to produce oxygen, which then oxidizes organic matter. Other common minerals on Mars, such as sulfates, may also produce oxygen upon thermal decay, presenting an additional complication. Different sulfate species decompose within a large range of temperatures. We performed a series of experiments on a sample containing the ferric sulfate jarosite. The sulfate ions within jarosite break down from 500°C. Carbon dioxide detected during heating of the sample was attributed to oxidation of organic matter. A laboratory standard of ferric sulfate hydrate released sulfur dioxide from 550°C, and an oxygen peak was detected in the products. Calcium sulfate did not decompose below 1000°C. Oxygen released from sulfate minerals may have already affected organic compound detection during in situ thermal experiments on Mars missions. A combination of preliminary mineralogical analyses and suitably selected pyrolysis temperatures may increase future success in the search for past or present life on Mars. Key Words: Mars—Life detection—Geochemistry—Organic matter—Jarosite. Astrobiology 15, 247–258. PMID:25695727
The MASSE Project: Applications of Biotechnology for Planetary Exploration
NASA Technical Reports Server (NTRS)
Lynch, Kennda; Steele, Andrew; Hedgecock, Jud; Wainwright, Norm; McKay, David S.; Maule, Jake; Schweitzer, Mary
2003-01-01
Automated life-detection experiments for solar system exploration have been previously. proposed and used onboard the. Viking, Mars lander,s, although. with ambiguous results. The recent advances in biotechnology such as biosensors, protein microarrays, and microfluidics alongside increased. knowledge in biomarker science have led to vastly improved sophistication and sensitivity for a new approach in life detection. The MASSE project has taken the challenge of integrating all of this knowledge into a new generation of interplanetary flight instrumentation for the main purpose.ot combining several mutually. confirming tests for life, organic/microbial contamination, prebiotic and abiotic chemicals into a small low powered instrument. Although the primary goal is interplanetary exploration, several terrestrial applications have become apparent specifically in point-of-care medical technology, bio-warfare, environmental sensing and microbial monitoring of manned space-flight vehicles.
Nucleic Acid Extraction from Synthetic Mars Analog Soils for in situ Life Detection
Mojarro, Angel; Ruvkun, Gary; Zuber, Maria T.
2017-01-01
Abstract Biological informational polymers such as nucleic acids have the potential to provide unambiguous evidence of life beyond Earth. To this end, we are developing an automated in situ life-detection instrument that integrates nucleic acid extraction and nanopore sequencing: the Search for Extra-Terrestrial Genomes (SETG) instrument. Our goal is to isolate and determine the sequence of nucleic acids from extant or preserved life on Mars, if, for example, there is common ancestry to life on Mars and Earth. As is true of metagenomic analysis of terrestrial environmental samples, the SETG instrument must isolate nucleic acids from crude samples and then determine the DNA sequence of the unknown nucleic acids. Our initial DNA extraction experiments resulted in low to undetectable amounts of DNA due to soil chemistry–dependent soil-DNA interactions, namely adsorption to mineral surfaces, binding to divalent/trivalent cations, destruction by iron redox cycling, and acidic conditions. Subsequently, we developed soil-specific extraction protocols that increase DNA yields through a combination of desalting, utilization of competitive binders, and promotion of anaerobic conditions. Our results suggest that a combination of desalting and utilizing competitive binders may establish a “universal” nucleic acid extraction protocol suitable for analyzing samples from diverse soils on Mars. Key Words: Life-detection instruments—Nucleic acids—Mars—Panspermia. Astrobiology 17, 747–760. PMID:28704064
NASA Astrophysics Data System (ADS)
Bonaccorsi, R.; Stoker, C. R.
2006-12-01
The subsurface is the key environment for searching for life on planets lacking surface life. This includes the search for past/present life on Mars where possible subsurface life could exist [1]. The Mars-Analog-Rio-Tinto-Experiment (MARTE) performed a simulation of a Mars robotic drilling at the RT Borehole#7 Site ~6.07m, atop a massive-pyrite deposit from the Iberian Pyritic Belt. The RT site is considered an important analog of Sinus Meridiani on Mars, an ideal model analog for a subsurface Martian setting [2], and a relevant example of deep subsurface microbial community including aerobic and anaerobic chemoautotrophs [4-5]. Searching for microbes or bulk organics of biological origin in a subsurface sample from a planet is a key scientific objective of Robotic drilling missions. During the 2005 Field experiment 28 minicores were robotically handled and subsampled for life detection experiments under anti-contamination protocols. Ground truth included visual observation of cores and lab based Elemental and Isotope Ratios Mass Spectrometry analysis (EA-IRMS) of bulk organics in Hematite and Gohetite-rich gossanized tuffs, gossan and clay layers within 0-6m-depth. C-org and N-tot vary up to four orders of magnitude among the litter (~11Wt%, 0-1cm) and the mineralized (~3Wt%, 1-3cm) layers, and the first 6 m-depth (C-org=0.02-0.38Wt%). Overall, the distribution/ preservation of plant and soil-derived organics (d13C-org = 26 per mil to 24 per mil) is ten times higher (C-org=0.33Wt%) that in hematite-poor clays, or where rootlets are present, than in hematite- rich samples (C-org=<0.01Wt%). This is consistent with ATP assay (Lightning-MVP, Biocontrol) for total biomass in subsurface (Borehole#7 ~6.07m, ~avg. 153RLU) vs. surface soil samples (~1,500-81,449RLU) [5]. However, the in-situ ATP assay failed in detecting presence of roots during the in-situ life detection experiment. Furthermore, cm-sized roots were overlooked during remote observations. Finally, ATP Luminometry provided insights for potential contamination from core-handling and environmental dust loadings on cleaned/sterilized control surfaces (e.g., 6,782-36,243RLU/cm2). Cleanliness/sterility can be maintained by applying a simple sterile protocol under field conditions. Science results from this research will support future Astrobiology driven drilling mission planned on Mars. Specifically, ground truth offers relevant insights to assess strengths and limits of in-situ/remote observations vs. laboratory measurements. Results from this experiment will also aid the debate on advantages/ disadvantages of manned vs. robotic drilling missions on Mars or other planets. [1] Boston et al., 1997; [2] http://marte.arc.nasa.gov; [3] Stoker, C., et al., 2006 AbSciCon, [4] Stoker et al., submitted; [5] Bonaccorsi., et al., 2006 AbSciCon.
Evaluation of sample preservation methods for space mission
NASA Technical Reports Server (NTRS)
Schubert, W.; Rohatgi, N.; Kazarians, G.
2002-01-01
For interplanetary spacecraft that will travel to destinations where future life detection experiments may be conducted or samples are to be returned to earth, we should archive and preserve relevant samples from the spacecraft and cleanrooms for evaluation at a future date.
NASA Technical Reports Server (NTRS)
Silverman, M. P.; Munoz, E. F.
1974-01-01
Experiments are reported which show that measuring metabolic activity in soil solutions by means of dynamic changes in electrical conductivity, water-soluble Ca, or water-soluble Mg is a feasible life detection method. The addition of 0.5% glucose solutions to 12 different air-dried soils always resulted in increases in all three of these parameters. The kinetics and magnitude of these changes for at least two and usually all three of the parameters over a 14-day period were clearly distinguishable from the changes in heat-sterilized controls or unsterilized controls without added glucose. In general, maximal values were achieved more rapidly under aerobic than under anaerobic incubation.
NASA Astrophysics Data System (ADS)
Wee, S. Y.; Edgcomb, V. P.; Burgaud, G.; Klein, F.; Schubotz, F.; Yvon-Lewis, S. A.; Sylvan, J. B.
2017-12-01
International Ocean Discovery Program (IODP) Expedition 360 represents the first leg of a multi-phase drilling program, SloMo, aimed at investigating the nature of the lower crust and Moho at slow spreading ridges. The goal of Expedition 360 was to recover a representative transect of the lower oceanic crust formed at Atlantis Bank, an oceanic core complex on the SW Indian Ridge. Recovered cores were primarily gabbro and olivine gabbro, which may potentially host serpentinization reactions and associated microbial life. Our goal was to sample this subseafloor environment and determine quantity, diversity and metabolic capabilities of any resident microbial life. Hole U1473A was drilled during Expedition 360 down to 790 m below seafloor and samples for detection of microbial communities and microbial biosignatures were collected throughout. We present here quantification of microbial biomass via fluorescence microscopy, preliminary analysis of nutrient addition experiments, data from sequencing of microbial 16S rRNA genes, analysis of microbial lipids, and data from Raman spectra of subsurface isolates. We initiated and sampled 12 nutrient addition experiments from 71-745 mbsf by adding sampled rocks to artificial seawater with no additions, added ammonium, added ammonium plus phosphate, and added organic acids. In nearly all of the experiment bottles, methane was detected when samples were collected at six months and again after one year of incubation. Phosphate in the incubations was drawn down, indicating active microbial metabolism, and archaeal lipids from in situ samples indicate the presence of methanogens, corroborating the likelihood of methanogens as the source of detected methane in the nutrient addition incubations. Altogether, the interdisciplinary approach used here provides a peek into life in the subseafloor upper ocean crust.
The processing of social stimuli in early infancy: from faces to biological motion perception.
Simion, Francesca; Di Giorgio, Elisa; Leo, Irene; Bardi, Lara
2011-01-01
There are several lines of evidence which suggests that, since birth, the human system detects social agents on the basis of at least two properties: the presence of a face and the way they move. This chapter reviews the infant research on the origin of brain specialization for social stimuli and on the role of innate mechanisms and perceptual experience in shaping the development of the social brain. Two lines of convergent evidence on face detection and biological motion detection will be presented to demonstrate the innate predispositions of the human system to detect social stimuli at birth. As for face detection, experiments will be presented to demonstrate that, by virtue of nonspecific attentional biases, a very coarse template of faces become active at birth. As for biological motion detection, studies will be presented to demonstrate that, since birth, the human system is able to detect social stimuli on the basis of their properties such as the presence of a semi-rigid motion named biological motion. Overall, the empirical evidence converges in supporting the notion that the human system begins life broadly tuned to detect social stimuli and that the progressive specialization will narrow the system for social stimuli as a function of experience. Copyright © 2011 Elsevier B.V. All rights reserved.
Cooperative Robotics and the Search for Extraterrestrial Life
NASA Technical Reports Server (NTRS)
Lupisella, M. L.
2000-01-01
If we think tenuous abodes of life may be hiding in remote extraterrestrial environmental niches, and if we want to assess the biological status of a given locale or entire planet before sending humans (perhaps because of contamination concerns or other motivations) then we face the challenge of robotically exploring a large space efficiently and in enough detail to have confidence in our assessment of the biological status of the environment in question. On our present schedule of perhaps two or so missions per opportunity, we will likely need a different exploratory approach than singular stationary landers or singular rover missions or sample return, because there appear to be fundamental limitations in these mission profiles to obtain the many samples we will likely need if we want to have confidence in assessing the biological status of an environment in which life could be hiding in remote environmental niches. Singular rover missions can potentially accommodate sampling over a fairly large area, but are still limited by range and can be a single point of failure. More importantly, such mission profiles have limited payload capabilities which are unlikely to meet the demanding requirements of life-detection. Sample return has the advantage of allowing sophisticated analysis of the sample, but also has the severe limitations associated with only being able to bring back a few samples. This presentation will suggest two cooperative robotic approaches for exploration that have the potential to overcome these difficulties and facilitate efficient and thorough life-detecting exploration of a large space. Given the two premises stated above, it appears at least two fundamental challenges have to be met simultaneously: (1) coverage of a large space and (2) bringing to bear a sophisticated suite of detection and experimental payloads on any specific location in order to address a major challenge in looking for extraterrestrial life: namely, executing a wide variety of detection scenarios and in situ experiments in order to gather the required data for a confident assessment that life has been detected and to, more generally, cover a wide range of extraterrestrial life possibilities. Cooperative robotics lends itself to this kind of problem because cooperation among the combined capabilities of a variety of simple single function agents can give rise to fairly complex task execution such as the search for and detection of extraterrestrial life.
Cooperative Robotics and the Search for Extraterrestrial Life
NASA Technical Reports Server (NTRS)
Lupisella, Mark L.
2000-01-01
If we think tenuous abodes of life may be hiding in remote extraterrestrial environmental niches, and if we want to assess the biological status of a given locale or entire planet before sending humans (perhaps because of contamination concerns or other motivations) then we face the challenge of robotically exploring a large space efficiently and in enough detail to have confidence in our assessment of the biological status of the environment in question. On our present schedule of perhaps two or so missions per opportunity, we will likely need a different exploratory approach than singular stationary landers or singular rover missions or sample return, because there appear to be fundamental limitations in these mission profiles to-obtain the many samples we will likely need if we want to have confidence in assessing the biological status of an environment in which life could be hiding in remote environmental niches. Singular rover missions can potentially accommodate sampling over a fairly large area, but are still limited by range and can be a single point of failure. More importantly, such mission profiles have limited payload capabilities which are unlikely to meet the demanding requirements of life-detection. Sample return has the advantage of allowing sophisticated analysis of the sample, but also has the severe limitations associated with only being able to bring back a few samples. This presentation will suggest two cooperative robotic approaches for exploration that have the potential to overcome these difficulties and facilitate efficient and thorough life-detecting exploration of a large space. Given the two premises state above, it appears at least two fundamental challenges have to be met simultaneously: coverage of a large space and bringing to bear a sophisticated suite of detection and experimental payloads on any specific location in order to address a major challenge in looking for extraterrestrial life: namely, executing a wide variety of detection scenarios and in situ experiments in order to gather the required data for a confident assessment that life has been detected and to, more generally, cover a wide range of extraterrestrial life possibilities. Cooperative robotics ]ends itself to this kind of problem because cooperation among the combined capabilities of a variety of simple single function agents can give rise to fairly complex task execution such as the search for and detection of extraterrestrial life.
2012-01-20
ultrasonic Lamb waves to plastic strain and fatigue life. Theory was developed and validated to predict second harmonic generation for specific mode... Fatigue and damage generation and progression are processes consisting of a series of interrelated events that span large scales of space and time...strain and fatigue life A set of experiments were completed that worked to relate the acoustic nonlinearity measured with Lamb waves to both the
Herbicide Persistence in Seawater Simulation Experiments
Mercurio, Philip; Mueller, Jochen F.; Eaglesham, Geoff; Flores, Florita; Negri, Andrew P.
2015-01-01
Herbicides are detected year-round in marine waters, including those of the World Heritage listed Great Barrier Reef (GBR). The few previous studies that have investigated herbicide persistence in seawater generally reported half-lives in the order of months, and several studies were too short to detect significant degradation. Here we investigated the persistence of eight herbicides commonly detected in the GBR or its catchments in standard OECD simulation flask experiments, but with the aim to mimic natural conditions similar to those found on the GBR (i.e., relatively low herbicide concentrations, typical temperatures, light and microbial communities). Very little degradation was recorded over the standard 60 d period (Experiment 1) so a second experiment was extended to 365 d. Half-lives of PSII herbicides ametryn, atrazine, diuron, hexazinone and tebuthiuron were consistently greater than a year, indicating high persistence. The detection of atrazine and diuron metabolites and longer persistence in mercuric chloride-treated seawater confirmed that biodegradation contributed to the breakdown of herbicides. The shortest half-life recorded was 88 d for growth-regulating herbicide 2,4-D at 31°C in the dark, while the fatty acid-inhibitor metolachlor exhibited a minimum half-life of 281 d. The presence of moderate light and elevated temperatures affected the persistence of most of the herbicides; however, the scale and direction of the differences were not predictable and were likely due to changes in microbial community composition. The persistence estimates here represent some of the first appropriate data for application in risk assessments for herbicide exposure in tropical marine systems. The long persistence of herbicides identified in the present study helps explain detection of herbicides in nearshore waters of the GBR year round. Little degradation of these herbicides would be expected during the wet season with runoff and associated flood plumes transporting a high proportion of the original herbicide from rivers into the GBR lagoon. PMID:26313296
Herbicide Persistence in Seawater Simulation Experiments.
Mercurio, Philip; Mueller, Jochen F; Eaglesham, Geoff; Flores, Florita; Negri, Andrew P
2015-01-01
Herbicides are detected year-round in marine waters, including those of the World Heritage listed Great Barrier Reef (GBR). The few previous studies that have investigated herbicide persistence in seawater generally reported half-lives in the order of months, and several studies were too short to detect significant degradation. Here we investigated the persistence of eight herbicides commonly detected in the GBR or its catchments in standard OECD simulation flask experiments, but with the aim to mimic natural conditions similar to those found on the GBR (i.e., relatively low herbicide concentrations, typical temperatures, light and microbial communities). Very little degradation was recorded over the standard 60 d period (Experiment 1) so a second experiment was extended to 365 d. Half-lives of PSII herbicides ametryn, atrazine, diuron, hexazinone and tebuthiuron were consistently greater than a year, indicating high persistence. The detection of atrazine and diuron metabolites and longer persistence in mercuric chloride-treated seawater confirmed that biodegradation contributed to the breakdown of herbicides. The shortest half-life recorded was 88 d for growth-regulating herbicide 2,4-D at 31°C in the dark, while the fatty acid-inhibitor metolachlor exhibited a minimum half-life of 281 d. The presence of moderate light and elevated temperatures affected the persistence of most of the herbicides; however, the scale and direction of the differences were not predictable and were likely due to changes in microbial community composition. The persistence estimates here represent some of the first appropriate data for application in risk assessments for herbicide exposure in tropical marine systems. The long persistence of herbicides identified in the present study helps explain detection of herbicides in nearshore waters of the GBR year round. Little degradation of these herbicides would be expected during the wet season with runoff and associated flood plumes transporting a high proportion of the original herbicide from rivers into the GBR lagoon.
Genetic Inventory Task Final Report. Volume 2
NASA Technical Reports Server (NTRS)
Venkateswaran, Kasthuri; LaDuc, Myron T.; Vaishampayan, Parag
2012-01-01
Contaminant terrestrial microbiota could profoundly impact the scientific integrity of extraterrestrial life-detection experiments. It is therefore important to know what organisms persist on spacecraft surfaces so that their presence can be eliminated or discriminated from authentic extraterrestrial biosignatures. Although there is a growing understanding of the biodiversity associated with spacecraft and cleanroom surfaces, it remains challenging to assess the risk of these microbes confounding life-detection or sample-return experiments. A key challenge is to provide a comprehensive inventory of microbes present on spacecraft surfaces. To assess the phylogenetic breadth of microorganisms on spacecraft and associated surfaces, the Genetic Inventory team used three technologies: conventional cloning techniques, PhyloChip DNA microarrays, and 454 tag-encoded pyrosequencing, together with a methodology to systematically collect, process, and archive nucleic acids. These three analysis methods yielded considerably different results: Traditional approaches provided the least comprehensive assessment of microbial diversity, while PhyloChip and pyrosequencing illuminated more diverse microbial populations. The overall results stress the importance of selecting sample collection and processing approaches based on the desired target and required level of detection. The DNA archive generated in this study can be made available to future researchers as genetic-inventory-oriented technologies further mature.
Reversed-phase high-performance liquid chromatography of sulfur mustard in water
DOE Office of Scientific and Technical Information (OSTI.GOV)
Raghuveeran, C.D.; Malhotra, R.C.; Dangi, R.S.
1993-01-01
A reversed-phase high-performance liquid chromatography method for the detection and quantitation of sulfur mustard (HD) in water is described with detection at 200 nm. The detection based on the solubility of HD in water revealed that extremely low quantities of HD (4 to 5 mg/L) only are soluble. Experience shows that water is still the medium of choice for the analysis of HD in water and aqueous effluents in spite of the minor handicap of its half-life of ca. 4 minutes, which only calls for speedy analysis.
Automated Microbial Metabolism Laboratory
NASA Technical Reports Server (NTRS)
1972-01-01
The Automated Microbial Metabolism Laboratory (AMML) 1971-1972 program involved the investigation of three separate life detection schemes. The first was a continued further development of the labeled release experiment. The possibility of chamber reuse without inbetween sterilization, to provide comparative biochemical information was tested. Findings show that individual substrates or concentrations of antimetabolites may be sequentially added to a single test chamber. The second detection system which was investigated for possible inclusion in the AMML package of assays, was nitrogen fixation as detected by acetylene reduction. Thirdly, a series of preliminary steps were taken to investigate the feasibility of detecting biopolymers in soil. A strategy for the safe return to Earth of a Mars sample prior to manned landings on Mars is outlined. The program assumes that the probability of indigenous life on Mars is unity and then broadly presents the procedures for acquisition and analysis of the Mars sample in a manner to satisfy the scientific community and the public that adequate safeguards are being taken.
Edwards, Howell G M
2007-10-01
The recognition of extinct or extant life signatures in the terrestrial geological record is fundamentally dependent upon the understanding of both the structural morphology and chemical composition of relict biomaterials; the identification of cyanobacterial colonies that have adapted biogeologically their mineral matrices in early evolutionary processes is a fundamental step in the acquisition of analytical data from remote planetary probes designed for life-detection experiments, particularly on Mars and on the planetary satellite moons, Europa and Titan. A key factor in the assessment of early life signatures is the molecular presence of chemicals designed to protect the emerging organisms from the damaging effect of radiation exposure and of desiccation and temperature changes; in this respect the non-destructive capability of Raman spectroscopy to delineate the interfacial interactions between substrates and endolithic biology is now deemed an essential part of the ExoMars life-detection suite of instrumentation planned by the European Space Agency in the AURORA programme. A description of the scientific basis for the biogeological discrimination offered by Raman spectroscopy between organic and inorganic moieties in specimens from terrestrial Mars analogue sites is followed by selected examples of the type of analytical information provided, which will be complementary to the elementary and microscopic data obtained from other instrumentation on the same mission.
The Viking mission search for life on Mars
NASA Technical Reports Server (NTRS)
Klein, H. P.; Lederberg, J.; Rich, A.; Horowitz, N. H.; Oyama, V. I.; Levin, G. V.
1976-01-01
The scientific payload on the Viking Mars landers is described. Shortly after landing, two facsimile cameras capable of stereoscopic imaging will scan the landing site area in black and white, color, and infrared to reveal gross evidence of past or present living systems. A wide range mass spectrometer will record a complete mass spectrum for soil samples from mass 12 to mass 200 every 10.3 sec. Three experiments based on different assumptions on the nature of life on Mars, if it exists, will be carried out by the bio-lab. A pyrolytic release experiment is designed to measure photosynthetic or dark fixation of carbon dioxide or carbon monoxide into organic compounds. A labelled release experiment will test for metabolic activity during incubation of a surface sample moistened with a solution of radioactively labelled simple organic compounds. A gas exchange experiment will detect changes in the gaseous medium surrounding a soil sample as the result of metabolic activity. The hardware, function, and terrestrial test results of the bio-lab experiments are discussed.
NASA Technical Reports Server (NTRS)
Cooper, John F.
2006-01-01
Accessible surfaces of the most likely astrobiological habitats (Mars, Europa, Titan) in the solar system beyond Earth are exposed to various chemical and hydrologic weathering processes directly or indirectly induced by interaction with the overlying space environment. These processes can be both beneficial, through provision of chemical compounds and energy, and destructive, through chemical dissociation or burial, to detectable presence of biosignatures. Orbital, suborbital, and surface platforms carrying astrobiological instrumentation must survive, and preferably exploit, space environment interactions to reach these habitats and search for evidence of life or its precursors. Experience from Mars suggests that any detection of biosignatures must be accompanied by characterization of the local chemical environment and energy sources including irradiation by solar ultraviolet photons and energetic particles from the space environment. Orbital and suborbital surveys of surface chemistry and astrobiological potential in the context of the space environment should precede targeted in-situ measurements to maximize probability of biosignature detection through site selection. The Space Physics of Life (SPOL) investigation has recently been proposed to the NASA Astrobiology Institute and is briefly described in this presentation. SPOL is the astrobiologically relevant study of the interactions and relationships of potentially? or previously inhabited, bodies of the solar system with the surrounding environments. This requires an interdisciplinary effort in space physics, planetary science, and radiation biology. The proposed investigation addresses the search for habitable environments, chemical resources to support life, and techniques for detection of organic and inorganic signs of life in the context of the space environment.
NASA Technical Reports Server (NTRS)
Wells, H. B.
1977-01-01
The preliminary data of the environmental control and life support subsystem for a space construction base manufacturing module was reported. A space processing module, which is capable of performing production biological experiments, was chosen as a baseline configuration. The primary assemblies and components considered for use were humidity and temperature control, ventilation fan, cabin fan, water separator, condensate storage, overboard dumping, distribution system, contaminant monitoring, cabin sensors, and fire and smoke detection.
[ETHICAL CONFLICTS AT THE END OF LIFE FROM NURSE PERCEPTION].
Calvo Rodríguez, Begoña; Berdial Cabal, Ignacio
2015-10-01
Current medicine tends to dehumanize the end of life process, which contributes to generate certain ethical conflict to nurse staff The major scientific datadas research. The four main ethical conflicts detected are: decisions making, communicating information, futile treatments and hydration and artificial feeding. The nurses suffer moral distress with ethical conflicts by the obligation of safeguard the dignity and rights of their patients. The lack of training and experience to treat ethical problems contribute to increase nurse disconfort.
Pediatric Coccidioidomycosis Patients: Perceptions, Quality of Life and Psychosocial Factors
Gaab, Erin Mary; Naeem, Fouzia
2015-01-01
Research investigating the effects of coccidioidomycosis (valley fever) on children and the psychosocial implications of this disease in general is lacking. This study reviews what is known about pediatric coccidioidomycosis patients. It documents the psychological functioning, quality of life, and illness perceptions of a sample of coccidioidomycosis patient families. Primary caregivers of pediatric patients and patients from a major hospital in the San Joaquin Valley of California were interviewed regarding their perceptions of disease detection, access to care and the patient/family experience. PMID:27417796
NASA Astrophysics Data System (ADS)
ten Kate, Inge L.
2010-08-01
Organics are expected to exist on Mars based on meteorite infall, in situ production, and any possible biological sources. Yet they have not been detected on the martian surface; are they there, or are we not capable enough to detect them? The Viking gas chromatograph-mass spectrometer did not detect organics in the headspace of heated soil samples with a detection limit of parts per billion. This null result strongly influenced the interpretation of the reactivity seen in the Viking biology experiments and led to the conclusion that life was not present and, instead, that there was some chemical reactivity in the soil. The detection of perchlorates in the martian soil by instruments on the Phoenix lander and the reports of methane in the martian atmosphere suggest that it may be time to reconsider the question of organics. The high-temperature oxidizing properties of perchlorate will promote combustion of organics in pyrolytic experiments and may have affected the ability of both Phoenix's organic analysis experiment and the Viking mass spectrometer experiments to detect organics. So the question of organics on Mars remains open. A primary focus of the upcoming Mars Science Laboratory will be the detection and identification of organic molecules by means of thermal volatilization, followed by gas chromatography - mass spectrometry - as was done on Viking. However, to enhance organic detectability, some of the samples will be processed with liquid derivatization agents that will dissolve organics from the soil before pyrolysis, which may separate them from the soil perchlorates. Nonetheless, the problem of organics on Mars is not solved, and for future missions other organic detection techniques should therefore be considered as well.
ten Kate, Inge L
2010-01-01
Organics are expected to exist on Mars based on meteorite infall, in situ production, and any possible biological sources. Yet they have not been detected on the martian surface; are they there, or are we not capable enough to detect them? The Viking gas chromatograph-mass spectrometer did not detect organics in the headspace of heated soil samples with a detection limit of parts per billion. This null result strongly influenced the interpretation of the reactivity seen in the Viking biology experiments and led to the conclusion that life was not present and, instead, that there was some chemical reactivity in the soil. The detection of perchlorates in the martian soil by instruments on the Phoenix lander and the reports of methane in the martian atmosphere suggest that it may be time to reconsider the question of organics. The high-temperature oxidizing properties of perchlorate will promote combustion of organics in pyrolytic experiments and may have affected the ability of both Phoenix's organic analysis experiment and the Viking mass spectrometer experiments to detect organics. So the question of organics on Mars remains open. A primary focus of the upcoming Mars Science Laboratory will be the detection and identification of organic molecules by means of thermal volatilization, followed by gas chromatography-mass spectrometry--as was done on Viking. However, to enhance organic detectability, some of the samples will be processed with liquid derivatization agents that will dissolve organics from the soil before pyrolysis, which may separate them from the soil perchlorates. Nonetheless, the problem of organics on Mars is not solved, and for future missions other organic detection techniques should therefore be considered as well.
Beyond detection: nuclear physics with a webcam in an educational setting
NASA Astrophysics Data System (ADS)
Pallone, A.; Barnes, P.
2016-09-01
Basic understanding of nuclear science enhances our daily-life experience in many areas, such as the environment, medicine, electric power generation, and even politics. Yet typical school curricula do not provide for experiments that explore the topic. We present a means by which educators can use the ubiquitous webcam and inexpensive sources of radiation to lead their students in a quantitative exploration of radioactivity, radiation, and the applications of nuclear physics.
When the Viking Missions Discovered Life on the Red Planet
NASA Astrophysics Data System (ADS)
Bianciardi, G.; Miller, J. D.; Straat, P. A.; Levin, G. V.
2012-09-01
The first (and only) dedicated life detection experiments on another planet were performed by the Viking Landers of 1976. In the Viking Labeled Release (LR) experiment of Levin and Straat, injections of organic compounds into Martian soil samples caused radioactive gas to evolve approaching plateaus of 10,000 - 15,000 cpm over several sols (Martian days). These "actives" were run at lander sites 1 and 2 with similar results. In contrast, the LR response to the 160o C control sample soils was very low. In conjunction with the active experiment results this negative result from the controls satisfied the pre-mission criteria for life. However, a controversy immediately arose concerning a biologic interpretation of the data. In an attempt to resolve this issue in the current work, we have employed complexity analysis of the Viking LR data for the initial six sols, and of terrestrial LR pilot studies using bacteria-laden, active soil (Biol 5) and sterilized soil (Biol 6). . Measures of mathematical complexity permitted a deep analysis of signal structure. Martian LR active response data were strongly superimposable upon the terrestrial biological time series, forming a welldefined cluster; and the heat-treated control samples, terrestrial and Martian, also clustered together, but distant from the active group, suggesting that the LR had, indeed, detected biological activity on Mars. The results presente herein are a key subset of the details published earlier by the same authors (IJASS, 13 (1), 14-26, 2012).
Graham, Bronwyn M; Richardson, Rick
2010-06-01
Fibroblast growth factor-2 (FGF2) is a potent neurotrophic factor that is involved in brain development and the formation of long-term memory. It has recently been shown that acute FGF2, administered at the time of learning, enhances long-term memory for contextual fear conditioning as well as extinction of conditioned fear in developing rats. As other research has shown that administering FGF2 on the first day of life leads to long-term morphological changes in the hippocampus, in the present study we investigated whether early life exposure to FGF2 affects contextual fear conditioning, and renewal following extinction, later in life. Experiment 1 demonstrated that a single injection of FGF2 on Postnatal Day (PND) 1 did not lead to any detectable changes in contextual fear conditioning in PND 16 or PND 23 rats. Experiments 2 and 3 demonstrated that 5 days of injections of FGF2 (from PND 1-5) facilitated contextual fear conditioning in PND 16 and PND 23 rats. Experiment 4 demonstrated that the observed facilitation of memory was not due to FGF2 increasing rats' sensitivity to foot shock. Experiment 5 showed that early life exposure to FGF2 did not affect learning about a discrete conditioned stimulus, but did allow PND 16 rats to use contextual information in more complex ways, leading to context-dependent extinction of conditioned fear. These results further implicate FGF2 as a critical signal involved in the development of learning and memory.
High-Precision Half-life Measurements for the Superallowed β+ Emitter 14O
NASA Astrophysics Data System (ADS)
Laffoley, A. T.; Svensson, C. E.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Blank, B.; Bouzomita, H.; Cross, D. S.; Diaz Varela, A.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Garrett, P. E.; Giovinazzo, J.; Grinyer, G. F.; Hackman, G.; Hadinia, B.; Jamieson, D. S.; Ketelhut, S.; Leach, K. G.; Leslie, J. R.; Tardiff, E. R.; Thomas, J. C.; Unsworth, C.
2014-03-01
The half-life of 14O, a superallowed Fermi β+ emitter, has been determined via simultaneous γ and β counting experiments at TRIUMF's Isotope Separator and Accelerator facility. Following the implantation of 14O samples at the center of the 8π spectrometer, a γ counting measurement was performed by detecting the 2313 keV γ-rays emitted from the first excited state of the daughter 14N using 20 high-purity germanium (HPGe) detectors. A simultaneous β counting experiment was performed using a fast plastic scintillator positioned directly behind the implantation site. The results, T½(γ) = 70:632 ± 0:094 s and T½(β) = 70:610 ± 0:030 s, are consistent with one another and, together with eight previous measurements, establish a new average for the 14O half-life of T½ = 70:619 ± 0:011 s with a reduced χ2 of 0.99.
Comparison of Next-Generation Sequencing Systems
Liu, Lin; Li, Yinhu; Li, Siliang; Hu, Ni; He, Yimin; Pong, Ray; Lin, Danni; Lu, Lihua; Law, Maggie
2012-01-01
With fast development and wide applications of next-generation sequencing (NGS) technologies, genomic sequence information is within reach to aid the achievement of goals to decode life mysteries, make better crops, detect pathogens, and improve life qualities. NGS systems are typically represented by SOLiD/Ion Torrent PGM from Life Sciences, Genome Analyzer/HiSeq 2000/MiSeq from Illumina, and GS FLX Titanium/GS Junior from Roche. Beijing Genomics Institute (BGI), which possesses the world's biggest sequencing capacity, has multiple NGS systems including 137 HiSeq 2000, 27 SOLiD, one Ion Torrent PGM, one MiSeq, and one 454 sequencer. We have accumulated extensive experience in sample handling, sequencing, and bioinformatics analysis. In this paper, technologies of these systems are reviewed, and first-hand data from extensive experience is summarized and analyzed to discuss the advantages and specifics associated with each sequencing system. At last, applications of NGS are summarized. PMID:22829749
NASA Astrophysics Data System (ADS)
Singh, Archana; Trivedi, Darshak R.
2017-05-01
A colorimetric receptor R 2-[(2-Hydroxy-naphthalen-1-ylmethylene)-hydrazonomethyl]-quinolin-8-ol has been designed and synthesized with good yield and characterized by the standard spectroscopic techniques such as FT-IR, UV-Visible, 1H NMR, 13C NMR and ESI-MS. The receptor R showed naked-eye detection and spectral change in the presence of F-, AcO- and H2PO4- over other anions. Interestingly, receptor R displaying high selective recognition towards F-, AcO- ion with a drastic color change from pale yellow to red in dry DMSO solvent and orange in mixed solvent DMSO/H2O (9:1, v/v). The behavior of receptor R towards F-, AcO- ion was investigated using UV-Vis and 1H NMR experiment. The detailed 1H NMR experiment result revealed that the receptor R is forming the hydrogen bonding between imine nitrogen and phenolic sbnd OH proton towards anions. The receptor R is able to detect sodium salts of flouride (NaF) and acetate (NaAcO) in aqueous medium and it exhibited dramatic color change from pale yellow to red. The receptor R demonstrated itself to be useful for real life application by detecting flouride and acetate ion in sea-water and commercially available product such as toothpaste, mouthwash and vinegar solution.
Neveu, Marc; Hays, Lindsay E; Voytek, Mary A; New, Michael H; Schulte, Mitchell D
2018-06-04
We describe the history and features of the Ladder of Life Detection, a tool intended to guide the design of investigations to detect microbial life within the practical constraints of robotic space missions. To build the Ladder, we have drawn from lessons learned from previous attempts at detecting life and derived criteria for a measurement (or suite of measurements) to constitute convincing evidence for indigenous life. We summarize features of life as we know it, how specific they are to life, and how they can be measured, and sort these features in a general sense based on their likelihood of indicating life. Because indigenous life is the hypothesis of last resort in interpreting life-detection measurements, we propose a small but expandable set of decision rules determining whether the abiotic hypothesis is disproved. In light of these rules, we evaluate past and upcoming attempts at life detection. The Ladder of Life Detection is not intended to endorse specific biosignatures or instruments for life-detection measurements, and is by no means a definitive, final product. It is intended as a starting point to stimulate discussion, debate, and further research on the characteristics of life, what constitutes a biosignature, and the means to measure them. Key Words: Life detection-Life-detection instruments-Biosignatures-Biomarkers. Astrobiology 18, xxx-xxx.
NASA Astrophysics Data System (ADS)
Baqué, M.; Dobrijevic, M.; Le Postollec, A.; Moreau, T.; Faye, C.; Vigier, F.; Incerti, S.; Coussot, G.; Caron, J.; Vandenabeele-Trambouze, O.
2017-01-01
Several instruments based on immunoassay techniques have been proposed for life-detection experiments in the framework of planetary exploration but few experiments have been conducted so far to test the resistance of antibodies against cosmic ray particles. We present several irradiation experiments carried out on both grafted and free antibodies for different types of incident particles (protons, neutrons, electrons and 12C) at different energies (between 9 MeV and 50 MeV) and different fluences. No loss of antibodies activity was detected for the whole set of experiments except when considering protons with energy between 20 and 30 MeV (on free and grafted antibodies) and fluences much greater than expected for a typical planetary mission to Mars for instance. Our results on grafted antibodies suggest that biochip-based instruments must be carefully designed according to the expected radiation environment for a given mission. In particular, a surface density of antibodies much larger than the expected proton fluence would prevent significant loss of antibodies activity and thus assuring a successful detection.
NASA Technical Reports Server (NTRS)
Stoker, Carol
2004-01-01
The discovery of near surface ground ice by the Mars Odyssey mission and the abundant evidence for recent Gulley features observed by the Mars Global Surveyor mission support longstanding theoretical arguments for subsurface liquid water on Mars. Thus, implementing the Mars program goal to search for life points to drilling on Mars to reach liquid water, collecting samples and analyzing them with instrumentation to detect in situ organisms and biomarker compounds. Searching for life in the subsurface of Mars will require drilling, sample extraction and handling, and new technologies to find and identify biomarker compounds and search for living organisms.
Neuroethology and life history adaptations of the elasmobranch electric sense.
Sisneros, Joseph A; Tricas, Timothy C
2002-01-01
The electric sense of elasmobranch fishes (sharks and rays) is an important sensory modality known to mediate the detection of bioelectric stimuli. Although the best known function for the use of the elasmobranch electric sense is prey detection, relatively few studies have investigated other possible biological functions. Here, we review recent studies that demonstrate the elasmobranch electrosensory system functions in a wide number of behavioral contexts including social, reproductive and anti-predator behaviors. Recent work on non-electrogenic stingrays demonstrates that the electric sense is used during reproduction and courtship for conspecific detection and localization. Electrogenic skates may use their electrosensory encoding capabilities and electric organ discharges for communication during social and reproductive interactions. The electric sense may also be used to detect and avoid predators during early life history stages in many elasmobranch species. Embryonic clearnose skates demonstrate a ventilatory freeze response when a weak low-frequency electric field is imposed upon the egg capsule. Peak frequency sensitivity of the peripheral electrosensory system in embryonic skates matches the low frequencies of phasic electric stimuli produced by natural fish egg-predators. Neurophysiology experiments reveal that electrosensory tuning changes across the life history of a species and also seasonally due to steroid hormone changes during the reproductive season. We argue that the ontogenetic and seasonal variation in electrosensory tuning represent an adaptive electrosensory plasticity that may be common to many elasmobranchs to enhance an individual's fitness throughout its life history.
Suicidal behaviour and suicide prevention in later life.
Draper, Brian M
2014-10-01
Despite a general decline in late life suicide rates over the last 30 years, older people have the highest rates of suicide in most countries. In contrast, non-fatal suicidal behaviour declines with age and more closely resembles suicide than in younger age groups. There are difficulties in the detection and determination of pathological suicidal ideation in older people. Multiple factors increase suicide risk ranging from distal early and mid-life issues such as child abuse, parental death, substance misuse and traumatic life experiences to proximal precipitants in late life such as social isolation and health-related concerns. Clinical depression is the most frequently identified proximal mental health concern and in many cases is a first episode of major depression. Recent studies have identified changes on neuroimaging and neurocognitive factors that might distinguish suicidal from non-suicidal depression in older people. Strategies for suicide prevention need to be 'whole of life' and, as no single prevention strategy is likely to be successful alone, a multi-faceted, multi-layered approach is required. This should include optimal detection and management of depression and of high risk individuals as available evidence indicates that this can reduce suicidal behaviour. How best to improve the quality of depression management in primary and secondary care requires further research. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Al-Shukri, H.; Eyuboglu, S.; Mahdi, H.
2005-12-01
Many geophysical techniques have been suggested as candidates for detecting water leakage in water distribution system, including ground penetrating radar (GPR), acoustic devices, and gas sampling devices. A series of laboratory experiments were conducted to determine the validity and effectiveness of GPR in detecting water leakage in metal and plastic PVC pipes. The goal was to derive a practical and robust procedure for detecting such leakage. Initially, prototype laboratory experiments were designed to simulate leaks in both PVC and metal pipe. The experiments were very well controlled and results obtained indicate that GPR is effective in detecting subsurface water leaks. This was followed by an outdoor life size experiments. 50 feet by 30 feet by 5 feet test bed was constructed using local soil and commercial water distribution pipes. A 400 MHz antenna was used to collect three-dimensional GPR data as a function of time for a number of experiments using different type of pipes. Advanced imaging and visualization technology was used to further analyze the data. The UALR Virtual Reality Center CAVE facilities were utilized to accomplish this test. Results obtained indicate that GPR is effective in detecting subsurface water leaks in both pipes. Synthetic models of the GPR signals based on Finite Difference Time Domain Method (FDTD) were built to help select an appropriate equipment configuration (frequency band, type of antenna, and real-time imaging software) prior to data acquisition. The simulation software was used to determine the near-field radiation characteristics of the GPR antenna. Different experimental models were adapted for which observational GPR data was previously collected. Matlab regression analysis was used to generate the incident waves for each model to ensure highly accurate and controlled experiments.
NASA Astrophysics Data System (ADS)
Horowitz, N. H.
1987-12-01
The shattering of the Lowellian picture of Mars by the Mount Wilson observation and Mariners 4, 6, and 7 is discussed. The Viking mission, instrumented to continue the search for life on Mars, did not detect even a trace of organic matter at the ppb-level of detectability. However, the experiments did indicate the presence of OH radicals (or peroxides derived from them) in the Martian soil. On Mars, OH would diffuse into the dry soil and there act as a strong oxidizing agent.
Input, flux, and persistence of six select pesticides in San Francisco Bay
Kuivila, K.M.; Jennings, B.E.
2007-01-01
Temporal patterns of pesticide inputs to San Francisco Bay were identified and correlated with timing of application and transport mechanism. Fluxes were calculated from measured concentrations and estimated flow. Persistence of the pesticides under typical riverine or estuarine conditions were estimated from laboratory experiments. Simazine was detected most frequently and had the highest flux into the Bay, which could be explained by its continuous use and long half-life. In comparison, diazinon was detected at lower concentrations and had a lower flux which corresponded to its lower use and shorter half-life. The order-of-magnitude lower fluxes of carbofuran and methidathion corresponded to their lower use and expected hydrolysis. Molinate was detected at the highest concentration but its flux was lower than expected, considering its very high use and persistence in the laboratory experiments. Additional loss of molinate is likely to occur from volatilization and photodegradation on the rice fields. Although thiobencarb had the second highest use, it had the lowest flux of the six pesticides, which can be attributed to its loss via hydrolysis, photodegradation, volatilization, and sorption to sediments. Fluxes into San Francisco Bay were equal to or greater than those reported for other estuaries, except for the Gulf of Mexico. ?? 2007 Taylor & Francis.
Exobiological exploration of Mars.
Klein, H P; DeVincenzi, D L
1995-03-01
Of all the other planets in the solar system, Mars remains the most promising for further elucidating concepts about chemical evolution and the origin of life. Strategies were developed to pursue three exobiological objectives for Mars exploration: determining the abundance and distribution of the biogenic elements and organic compounds, detecting evidence of an ancient biota on Mars, and determining whether indigenous organisms exist anywhere on the planet. The three strategies are quite similar and, in fact, share the same sequence of phases. In the first phase, each requires global reconnaissance and remote sensing by orbiters to select sites of interest for detailed in situ analyses. In the second phase, lander missions are conducted to characterize the chemical and physical properties of the selected sites. The third phase involves conducting "critical" experiments at sites whose properties make them particularly attractive for exobiology. These critical experiments would include, for example, identification of organics, detection of fossils, and detection of extant life. The fourth phase is the detailed analysis of samples returned from these sites in Earth-based laboratories to confirm and extend previous discoveries. Finally, in the fifth phase, human exploration is needed to establish the geological settings for the earlier findings or to discover and explore sites that are not accessible to robotic spacecraft.
NASA Astrophysics Data System (ADS)
Storrie-Lombardi, Michael C.; Sattler, Birgit
2009-08-01
Once thought to be a barren desert devoid of life, it now appears that Earth's cryosphere is an ice ecosystem harbouring a rich community of metabolically active microorganisms inhabiting ice, snow, water, and lithic environments. The ability to rapidly survey this ecosystem during in situ and orbital missions is of considerable interest for monitoring Earth's carbon budget and for efficiently searching for life on Mars or any exoplanet with an analogous cryosphere. Laser induced fluorescence emission (L.I.F.E.) imaging and spectroscopy using excitation in ultraviolet (UV) wavelengths have been proposed as non-destructive astrobiological survey tools to search for amino acids, nucleic acids, microbial life, and polycyclic aromatic hydrocarbons (PAHs) deep in the Mars regolith. However, the technique is easily adapted to search for larger, more complex biomolecular targets using longer wavelength sources. Of particular interest is the ability for excitation at blue, green, and red wavelengths to produce visible and near infrared fluorescence of photosynthetic pigments in cyanobacteria-dominated microbial communities populating the ice of alpine, Arctic, and Antarctic lakes, glaciers, ice sheets, and even the supercooled water-ice droplets of clouds. During the Tawani 2008 International Antarctic Expedition we tested the in situ use of the technique as part of a field campaign in the Dry Valleys of Schirmacher Oasis and Lake Untersee, Queen Maud Land, Antarctica. In the spring of 2009, we performed airborne remote sensing tests of the technology in Alaska. In this paper we review our in situ laser detection experiments and present for the first time preliminary results on our efforts to detect cryosphere L.I.F.E. from an airborne platform.
Simple gas chromatographic system for analysis of microbial respiratory gases
NASA Technical Reports Server (NTRS)
Carle, G. C.
1972-01-01
Dual column ambient temperature system, consisting of pair of capillary columns, microbead thermistor detector and micro gas-sampling valve, is used in remote life-detection equipment for space experiments. Performance outweighs advantage gained by utilizing single-column systems to reduce weight, conserve carrier gas and operate at lower power levels.
Fungal leaching of titanium from rock.
NASA Technical Reports Server (NTRS)
Silverman, M. P.; Munoz, E. F.
1971-01-01
Penicillium simplicissimum is found to solubilize up to 80% of the titanium in granitic rocks but less than 2% of the titanium in basaltic rocks. These findings were made in investigating the interactions of microorganisms with rocks and minerals of the biosphere in studies aimed at developing experiments for the detection of extraterrestrial life.
Microbiology studies in the Space Shuttle
NASA Technical Reports Server (NTRS)
Taylor, G. R.
1976-01-01
Past space microbiology studies have evaluated three general areas: microbe detection in extraterrestrial materials; monitoring of autoflora and medically important species on crewmembers, equipment, and cabin air; and in vitro evaluations of isolated terrestrial species carried on manned and unmanned spaceflights. These areas are briefly reviewed to establish a basis for presenting probable experiment subjects applicable to the Space Shuttle era. Most extraterrestrial life detection studies involve visitations to other heavenly bodies. Although this is not applicable to the first series of Shuttle flights, attempts to capture meteors and spores in space could be important. Human pathogen and autoflora monitoring will become more important with increased variety among crewmembers. Inclusion of contaminated animal and plant specimens in the space lab will necessitate inflight evaluation of cross-contamination and infection potentials. The majority of Shuttle microbiology studies will doubtless fall into the third study area. Presence of a space lab will permit a whole range of experimentation under conditions similar to these experienced in earth-based laboratories. The recommendations of various study groups are analyzed, and probable inflight microbiological experiment areas are identified for the Life Sciences Shuttle Laboratory.
Williams, Veronika; Victor, Christina R; McCrindle, Rachel
2013-01-01
Background. Falls and fear of falling present a major risk to older people as both can affect their quality of life and independence. Mobile assistive technologies (AT) fall detection devices may maximise the potential for older people to live independently for as long as possible within their own homes by facilitating early detection of falls. Aims. To explore the experiences and perceptions of older people and their carers as to the potential of a mobile falls detection AT device. Methods. Nine focus groups with 47 participants including both older people with a range of health conditions and their carers. Interviews were audio recorded, transcribed verbatim, and thematically analysed. Results. Four key themes were identified relating to participants' experiences and perceptions of falling and the potential impact of a mobile falls detector: cause of falling, falling as everyday vulnerability, the environmental context of falling, and regaining confidence and independence by having a mobile falls detector. Conclusion. The perceived benefits of a mobile falls detector may differ between older people and their carers. The experience of falling has to be taken into account when designing mobile assistive technology devices as these may influence perceptions of such devices and how older people utilise them.
NASA Astrophysics Data System (ADS)
Parro, Víctor; Fernández-Calvo, Patricia; Rodríguez Manfredi, José A.; Moreno-Paz, Mercedes; Rivas, Luis A.; García-Villadangos, Miriam; Bonaccorsi, Rosalba; González-Pastor, José Eduardo; Prieto-Ballesteros, Olga; Schuerger, Andrew C.; Davidson, Mark; Gómez-Elvira, Javier; Stoker, Carol R.
2008-10-01
A field prototype of an antibody array-based life-detector instrument, Signs Of LIfe Detector (SOLID2), has been tested in a Mars drilling mission simulation called MARTE (Mars Astrobiology Research and Technology Experiment). As one of the analytical instruments on the MARTE robotic drilling rig, SOLID2 performed automatic sample processing and analysis of ground core samples (0.5 g) with protein microarrays that contained 157 different antibodies. Core samples from different depths (down to 5.5 m) were analyzed, and positive reactions were obtained in antibodies raised against the Gram-negative bacterium Leptospirillum ferrooxidans, a species of the genus Acidithiobacillus (both common microorganisms in the Río Tinto area), and extracts from biofilms and other natural samples from the Río Tinto area. These positive reactions were absent when the samples were previously subjected to a high-temperature treatment, which indicates the biological origin and structural dependency of the antibody-antigen reactions. We conclude that an antibody array-based life-detector instrument like SOLID2 can detect complex biological material, and it should be considered as a potential analytical instrument for future planetary missions that search for life.
Parro, Víctor; Fernández-Calvo, Patricia; Rodríguez Manfredi, José A; Moreno-Paz, Mercedes; Rivas, Luis A; García-Villadangos, Miriam; Bonaccorsi, Rosalba; González-Pastor, José Eduardo; Prieto-Ballesteros, Olga; Schuerger, Andrew C; Davidson, Mark; Gómez-Elvira, Javier; Stoker, Carol R
2008-10-01
A field prototype of an antibody array-based life-detector instrument, Signs Of LIfe Detector (SOLID2), has been tested in a Mars drilling mission simulation called MARTE (Mars Astrobiology Research and Technology Experiment). As one of the analytical instruments on the MARTE robotic drilling rig, SOLID2 performed automatic sample processing and analysis of ground core samples (0.5 g) with protein microarrays that contained 157 different antibodies. Core samples from different depths (down to 5.5 m) were analyzed, and positive reactions were obtained in antibodies raised against the Gram-negative bacterium Leptospirillum ferrooxidans, a species of the genus Acidithiobacillus (both common microorganisms in the Río Tinto area), and extracts from biofilms and other natural samples from the Río Tinto area. These positive reactions were absent when the samples were previously subjected to a high-temperature treatment, which indicates the biological origin and structural dependency of the antibody-antigen reactions. We conclude that an antibody array-based life-detector instrument like SOLID2 can detect complex biological material, and it should be considered as a potential analytical instrument for future planetary missions that search for life.
Analysis and interpretation of Viking labeled release experimental results
NASA Technical Reports Server (NTRS)
Levin, G. V.
1979-01-01
The Viking Labeled Release (LR) life detection experiment on the surface of Mars produced data consistent with a biological interpretation. In considering the plausibility of this interpretation, terrestrial life forms were identified which could serve as models for Martian microbial life. Prominent among these models are lichens which are known to survive for years in a state of cryptobiosis, to grow in hostile polar environments, to exist on atmospheric nitrogen as sole nitrogen source, and to survive without liquid water by absorbing water directly from the atmosphere. Another model is derived from the endolithic bacteria found in the dry Antarctic valleys; preliminary experiments conducted with samples of these bacteria indicate that they produce positive LR responses approximating the Mars results. However, because of the hositility of the Martian environment to life, and the failure to find organics on the surface of Mars, a number of nonbiological explanations were advanced to account for the Viking LR data. A reaction of the LR nutrient with putative surface hydrogen peroxide is the leading candidate. Other possibilities raised include reactions caused by or with ultraviolet irradiation, gamma-Fe2O3, metalloperoxides or superoxides.
Decision-Making Regarding Mammography Screening for Older Women.
Schonberg, Mara A
2016-12-01
The population is aging, and breast cancer incidence increases with age, peaking between the ages of 75 and 79. However, it is not known whether mammography screening helps women aged 75 and older live longer because they have not been included in randomized controlled trials evaluating mammography screening. Guidelines recommend that older women with less than a 10-year life expectancy not be screened because it takes approximately 10 years before a screen-detected breast cancer may affect an older woman's survival. Guidelines recommend that clinicians discuss the benefits and risks of screening with women aged 75 and older with a life expectancy of 10 years or longer to help them elicit their values and preferences. It is estimated that two of 1,000 women who continue to be screened every other year from age 70 to 79 may avoid breast cancer death, but 12% to 27% of these women will experience a false-positive test, and 10% to 20% of women who experience a false-positive test will undergo a breast biopsy. In addition, approximately 30% of screen-detected cancers would not otherwise have shown up in an older woman's lifetime, yet nearly all older women undergo treatment for these breast cancers, and the risks of treatment increase with age. To inform decision-making, tools are available to estimate life expectancy and to educate older women about the benefits and harms of mammography screening. Guides are also available to help clinicians discuss stopping screening with older women with less than a 10-year life expectancy. Ideally, screening decisions would consider an older woman's life expectancy, breast cancer risk, and her values and preferences. © 2016, Copyright the Authors Journal compilation © 2016, The American Geriatrics Society.
Magnetoelastic Effect-Based Transmissive Stress Detection for Steel Strips: Theory and Experiment
Zhang, Qingdong; Su, Yuanxiao; Zhang, Liyuan; Bi, Jia; Luo, Jiang
2016-01-01
For the deficiencies of traditional stress detection methods for steel strips in industrial production, this paper proposes a non-contact stress detection scheme based on the magnetoelastic effect. The theoretical model of the transmission-type stress detection is established, in which the output voltage and the tested stress obey a linear relation. Then, a stress detection device is built for the experiment, and Q235 steel under uniaxial tension is tested as an example. The result shows that the output voltage rises linearly with the increase of the tensile stress, consistent with the theoretical prediction. To ensure the accuracy of the stress detection method in actual application, the temperature compensation, magnetic shielding and some other key technologies are investigated to reduce the interference of the external factors, such as environment temperature and surrounding magnetic field. The present research develops the theoretical and experimental foundations for the magnetic stress detection system, which can be used for online non-contact monitoring of strip flatness-related stress (tension distribution or longitudinal residual stress) in the steel strip rolling process, the quality evaluation of strip flatness after rolling, the life and safety assessment of metal construction and other industrial production links. PMID:27589742
Detection of density dependence requires density manipulations and calculation of lambda.
Fowler, N L; Overath, R Deborah; Pease, Craig M
2006-03-01
To investigate density-dependent population regulation in the perennial bunchgrass Bouteloua rigidiseta, we experimentally manipulated density by removing adults or adding seeds to replicate quadrats in a natural population for three annual intervals. We monitored the adjacent control quadrats for 14 annual intervals. We constructed a population projection matrix for each quadrat in each interval, calculated lambda, and did a life table response experiment (LTRE) analysis. We tested the effects of density upon lambda by comparing experimental and control quadrats, and by an analysis of the 15-year observational data set. As measured by effects on lambda and on N(t+1/Nt in the experimental treatments, negative density dependence was strong: the population was being effectively regulated. The relative contributions of different matrix elements to treatment effect on lambda differed among years and treatments; overall the pattern was one of small contributions by many different life cycle stages. In contrast, density dependence could not be detected using only the observational (control quadrats) data, even though this data set covered a much longer time span. Nor did experimental effects on separate matrix elements reach statistical significance. These results suggest that ecologists may fail to detect density dependence when it is present if they have only descriptive, not experimental, data, do not have data for the entire life cycle, or analyze life cycle components separately.
Figueredo, Federico; Cortón, Eduardo; Abrevaya, Ximena C
2015-09-01
Microbial fuel cells (MFCs) are bioelectrochemical systems (BES) capable of harvesting electrons from redox reactions involved in metabolism. In a previous work, we used chemoorganoheterotrophic microorganisms from the three domains of life-Bacteria, Archaea, and Eukarya-to demonstrate that these BES could be applied to the in situ detection of extraterrestrial life. Since metabolism can be considered a common signature of life "as we know it," we extended in this study the ability to use MFCs as sensors for photolithoautotrophic metabolisms. To achieve this goal, two different photosynthetic microorganisms were used: the microalgae Parachlorella kessleri and the cyanobacterium Nostoc sp. MFCs were loaded with nonsterilized samples, sterilized samples, or sterilized culture medium of both microorganisms. Electric potential measurements were recorded for each group in single experiments or in continuum during light-dark cycles, and power and current densities were calculated. Our results indicate that the highest power and current density values were achieved when metabolically active microorganisms were present in the anode of the MFC. Moreover, when continuous measurements were performed during light-dark cycles, it was possible to see a positive response to light. Therefore, these BES could be used not only to detect chemoorganoheterotrophic metabolisms but also photolithoautotrophic metabolisms, in particular those involving oxygenic photosynthesis. Additionally, the positive response to light when using these BES could be employed to distinguish photosynthetic from nonphotosynthetic microorganisms in a sample.
Microfluidics microFACS for Life Detection
NASA Technical Reports Server (NTRS)
Platt, Donald W.; Hoover, Richard B.
2010-01-01
A prototype micro-scale Fluorescent Activated Cell Sorter (microFACS) for life detection has been built and is undergoing testing. A functional miniature microfluidics instrument with the ability to remotely distinguish live or dead bacterial cells from abiotic particulates in ice or permafrost of icy bodies of the solar system would be of fundamental value to NASA. The use of molecular probes to obtain the bio-signature of living or dead cells could answer the most fundamental question of Astrobiology: Does life exist beyond Earth? The live-dead fluorescent stains to be used in the microFACS instrument function only with biological cell walls. The detection of the cell membranes of living or dead bacteria (unlike PAH's and many other Biomarkers) would provide convincing evidence of present or past life. This miniature device rapidly examine large numbers of particulates from a polar ice or permafrost sample and distinguish living from dead bacteria cells and biological cells from mineral grains and abiotic particulates and sort the cells and particulates based on a staining system. Any sample found to exhibit fluorescence consistent with living cells could then be used in conjunction with a chiral labeled release experiment or video microscopy system to seek addition evidence for cellular metabolism or motility. Results of preliminary testing and calibration of the microFACS prototype instrument system with pure cultures and enrichment assemblages of microbial extremophiles will be reported.
Life science experiments performed in space in the ISS/Kibo facility and future research plans
Ohnishi, Takeo
2016-01-01
Over the past several years, current techniques in molecular biology have been used to perform experiments in space, focusing on the nature and effects of space radiation. In the Japanese ‘Kibo’ facility in the International Space Station (ISS), the Japan Aerospace Exploration Agency (JAXA) has performed five life science experiments since 2009, and two additional experiments are currently in progress. The first life science experiment in space was the ‘Rad Gene’ project, which utilized two human cultured lymphoblastoid cell lines containing a mutated p53 gene (mp53) and a parental wild-type p53 gene (wtp53) respectively. Four parameters were examined: (i) detecting space radiation–induced DSBs by observing γH2AX foci; (ii) observing p53-dependent gene expression during space flight; (iii) observing p53-dependent gene expression after space flight; and (iv) observing the adaptive response in the two cell lines containing the mutated and wild type p53 genes after exposure to space radiation. These observations were completed and have been reported, and this paper is a review of these experiments. In addition, recent new information from space-based experiments involving radiation biology is presented here. These experiments involve human cultured cells, silkworm eggs, mouse embryonic stem cells and mouse eggs in various experiments designed by other principal investigators in the ISS/Kibo. The progress of Japanese science groups involved in these space experiments together with JAXA are also discussed here. The Japanese Society for Biological Sciences in Space (JSBSS), the Utilization Committee of Space Environment Science (UCSES) and the Science Council of Japan (ACJ) have supported these new projects and new experimental facilities in ISS/Kibo. Currently, these organizations are proposing new experiments for the ISS through 2024. PMID:27130692
Akers, Katherine G; Yang, Zhen; DelVecchio, Dominic P; Reeb, Bethany C; Romeo, Russell D; McEwen, Bruce S; Tang, Akaysha C
2008-06-30
Early experience is known to have a profound impact on brain and behavioral function later in life. Relatively few studies, however, have examined whether the effects of early experience remain detectable in the aging animal. Here, we examined the effects of neonatal novelty exposure, an early stimulation procedure, on late senescent rats' ability to win in social competition. During the first 3 weeks of life, half of each litter received daily 3-min exposures to a novel environment while the other half stayed in the home cage. At 24 months of age, pairs of rats competed against each other for exclusive access to chocolate rewards. We found that novelty-exposed rats won more rewards than home-staying rats, indicating that early experience exerts a life-long effect on this aspect of social dominance. Furthermore, novelty-exposed but not home-staying rats exhibited habituation of corticosterone release across repeated days of social competition testing, suggesting that early experience permanently enhances plasticity of the stress response system. Finally, we report a surprising finding that across individual rat families, greater effects of neonatal novelty exposure on stress response plasticity were found among families whose dams provided more reliable, instead of a greater total quantity of, maternal care.
Polygraph lie detection on real events in a laboratory setting.
Bradley, M T; Cullen, M C
1993-06-01
This laboratory study dealt with real-life intense emotional events. Subjects generated embarrassing stories from their experience, then submitted to polygraph testing and, by lying, denied their stories and, by telling the truth, denied a randomly assigned story. Money was given as an incentive to be judged innocent on each story. An interrogator, blind to the stories, used Control Question Tests and found subjects more deceptive when lying than when truthful. Stories interacted with order such that lying on the second story was more easily detected than lying on the first. Embarrassing stories provide an alternative to the use of mock crimes to study lie detection in the laboratory.
Studies related to the development of the Viking 1975 labeled release experiment
NASA Technical Reports Server (NTRS)
Devincenzi, D. L.; Deal, P. H.
1976-01-01
The labeled release life detection experiment on the Viking 1975 Mars mission is based on the concept that microorganisms will metabolize radioactive organic substrates in a nutrient medium and release radioactive carbon dioxide. Several experiments, using laboratory equipment, were carried out to evaluate various aspects of the concept. Results indicate: (1) label is released by sterilization-treated soil, (2) substantial quantities of label are retained in solution under basic conditions, (3) the substrate used, as well as position of label in the molecule, affect release of label, (4) label release is depressed by radiolytic decomposition of substrates, and (5) About 100,000 organisms are required to produce a detectable response. These results, suggest additional areas for testing, add to the data base for interpretation of flight results, and have significance for broader application of this technique for assessing microbial activity.
The Subjective and Objective Interface of Bias Detection on Language Tests
ERIC Educational Resources Information Center
Ross, Steven J.; Okabe, Junko
2006-01-01
Test validity is predicated on there being a lack of bias in tasks, items, or test content. It is well-known that factors such as test candidates' mother tongue, life experiences, and socialization practices of the wider community may serve to inject subtle interactions between individuals' background and the test content. When the gender of the…
High-precision half-life measurements for the superallowed Fermi β+ emitter 14O
NASA Astrophysics Data System (ADS)
Laffoley, A. T.; Svensson, C. E.; Andreoiu, C.; Austin, R. A. E.; Ball, G. C.; Blank, B.; Bouzomita, H.; Cross, D. S.; Diaz Varela, A.; Dunlop, R.; Finlay, P.; Garnsworthy, A. B.; Garrett, P. E.; Giovinazzo, J.; Grinyer, G. F.; Hackman, G.; Hadinia, B.; Jamieson, D. S.; Ketelhut, S.; Leach, K. G.; Leslie, J. R.; Tardiff, E.; Thomas, J. C.; Unsworth, C.
2013-07-01
The half-life of the superallowed Fermi β+ emitter 14O has been determined via simultaneous direct β and γ counting experiments at TRIUMF's Isotope Separator and Accelerator (ISAC) facility. A γ-ray counting measurement was performed by detecting the 2312.6-keV γ rays emitted from an excited state of the daughter 14N following the implantation of samples at the center of the 8π γ-ray spectrometer, a spherical array of 20 high-purity germanium (HPGe) detectors. A simultaneous β counting experiment was performed using a fast plastic scintillator positioned behind the implantation site with a solid angle coverage of ˜20%. The results, T1/2(β)=70.610±0.030s and T1/2(γ)=70.632±0.094s, form a consistent set and, together with eight previous measurements, establish a new average for the 14O half-life of T1/2=70.619±0.011s with a reduced χ2 of 0.99.
Nucleic Acid Extraction from Synthetic Mars Analog Soils for in situ Life Detection
NASA Astrophysics Data System (ADS)
Mojarro, Angel; Ruvkun, Gary; Zuber, Maria T.; Carr, Christopher E.
2017-08-01
Biological informational polymers such as nucleic acids have the potential to provide unambiguous evidence of life beyond Earth. To this end, we are developing an automated in situ life-detection instrument that integrates nucleic acid extraction and nanopore sequencing: the Search for Extra-Terrestrial Genomes (SETG) instrument. Our goal is to isolate and determine the sequence of nucleic acids from extant or preserved life on Mars, if, for example, there is common ancestry to life on Mars and Earth. As is true of metagenomic analysis of terrestrial environmental samples, the SETG instrument must isolate nucleic acids from crude samples and then determine the DNA sequence of the unknown nucleic acids. Our initial DNA extraction experiments resulted in low to undetectable amounts of DNA due to soil chemistry-dependent soil-DNA interactions, namely adsorption to mineral surfaces, binding to divalent/trivalent cations, destruction by iron redox cycling, and acidic conditions. Subsequently, we developed soil-specific extraction protocols that increase DNA yields through a combination of desalting, utilization of competitive binders, and promotion of anaerobic conditions. Our results suggest that a combination of desalting and utilizing competitive binders may establish a "universal" nucleic acid extraction protocol suitable for analyzing samples from diverse soils on Mars.
Agostini, Francesca; Neri, Erica; Salvatori, Paola; Dellabartola, Sara; Bozicevic, Laura; Monti, Fiorella
2015-05-01
This study aimed to identify different kinds of stressful life events and social support associated with antenatal depressive symptoms in a sample of pregnant Italian women. We conducted the study at a primary health-care centre in an urban area (northeast Italy). Mainly recruited at antenatal classes, 404 eligible pregnant women completed a socio-demographic questionnaire that included questions about the present pregnancy, the Edinburgh Depression Scale (EDS) to estimate the prevalence of depressive symptoms, the Multidimensional Scale of Perceived Social Support and List of Threatening Experiences Questionnaire to investigate the quality and nature of social support and recent negative life events. Of the 404 women, 60 (14.9 %) scored 13 or higher on the EDS. This group reported significantly lower social support from various sources-family, friends, and significant others; only in primiparous women were depressive symptoms significantly related to lower support from friends. Women with EDS scores equal or higher than 13 also reported a higher occurrence of recent stressful life events-specifically, death or a serious problem with a close friend or relative, unemployment, financial problems, and moving or housing difficulties. Regression analyses showed that women with high levels of social support or with a positive experience of pregnancy were less likely to experience antenatal depressive symptoms. Our results underscore the associations among antenatal depression, specific life stressors, and low social support from various sources. Clinical attention to these psychosocial correlates is recommended toward detecting vulnerability to antenatal depressive symptoms.
A non-earthcentric approach to life detection
NASA Technical Reports Server (NTRS)
Conrad, P. G.; Nealson, K. H.
2001-01-01
The ultimate goal of a comprehensive life detection strategy is never to miss life when we encounter it. To accomplish this goal, we must define life in universal, that is, non-Earthcentric, measurable terms. Next, we must understand the nature of biosignatures observed from the measured parameters of life. And finally, we must have a clear idea of the end-member states for the search--what does life, past life, or no life look like (in terms of the measured parameters) at multiple spatial and temporal scales? If we can approach these problems both in the laboratory and in the field on Earth, then we have a chance of being able to detect life elsewhere in our solar system. What are the required limits of detection at each of those scales? What spatial, spectral, and temporal resolutions are necessary to detect life? These questions are actively being investigated in our group, and in this report, we present our strategy and approach to non-Earthcentric life detection.
Detection of dehydration by using volume kinetics.
Zdolsek, Joachim; Li, Yuhong; Hahn, Robert G
2012-10-01
Patients admitted to surgery may be dehydrated, which is difficult to diagnose except when it is severe (>5% Gl116 of the body weight). We hypothesized that modest dehydration can be detected by kinetic analysis of the blood hemoglobin concentration after a bolus infusion of crystalloid fluid. Four series of experiments were performed on 10 conscious, healthy male volunteers. Separated by at least 2 days, they received 5 or 10 mL/kg acetated Ringer's solution over 15 minutes. Before starting half of the IV infusions, volume depletion amounting to 1.5 to 2.0 L (approximately 2% of body weight) was induced with furosemide. The elimination clearance and the half-life of the infused fluid were calculated based on blood hemoglobin over 120 minutes. The perfusion index and the pleth variability index were monitored by pulse oximetry after a change of body position. Dehydration decreased the elimination clearance of acetated Ringer's solution [median (25th-75th percentile)] from 1.84 (1.23-2.57) to 0.53 (0.41-0.79) mL/kg/min (Wilcoxon matched-pair test P < 0.001) and increased the half-life from 23 (12-37) to 76 (57-101) minutes (P < 0.001). The smaller infusion, 5 mL/kg, fully discriminated between experiments performed in the euhydrated and dehydrated states, whereas the urinary excretion provided a less-reliable indication of hydration status. Dehydration decreased the perfusion index but did not affect the pleth variability index. Dehydration amounting to 2% of the body weight could be detected from the elimination clearance and the half-life of an infusion of 5 mL/kg Ringer's solution.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, Adam; Pratt, L.M.; Vishnivetskaya, Tatiana A
2011-01-01
Recent orbital and landed missions have provided substantial evidence for ancient liquid water on the martian surface as well as evidence of more recent sedimentary deposits formed by water and/or ice. These observations raise serious questions regarding an independent origin and evolution of life on Mars. Future missions seek to identify signs of extinct martian biota in the form of biomarkers or morphological characteristics, but the inherent danger of spacecraft-borne terrestrial life makes the possibility of forward contamination a serious threat not only to the life detection experiments, but also to any extant martian ecosystem. A variety of cold andmore » desiccation-tolerant organisms were exposed to 40 days of simulated martian surface conditions while embedded within several centimeters of regolith simulant in order to ascertain the plausibility of such organisms survival as a function of environmental parameters and burial depth. Relevant amino acid biomarkers associated with terrestrial life were also analyzed in order to understand the feasibility of detecting chemical evidence for previous biological activity. Results indicate that stresses due to desiccation and oxidation were the primary deterrent to organism survival, and that the effects of UV-associated damage, diurnal temperature variations, and reactive atmospheric species were minimal. Organisms with resistance to desiccation and radiation environments showed increased levels of survival after the experiment compared to organisms characterized as psychrotolerant. Amino acid analysis indicated the presence of an oxidation mechanism that migrated downward through the samples during the course of the experiment and likely represents the formation of various oxidizing species at mineral surfaces as water vapor diffused through the regolith. Current sterilization protocols may specifically select for organisms best adapted to survival at the martian surface, namely species that show tolerance to radical-induced oxidative damage and low water activity environments. Additionally, any hypothetical martian ecosystems may have evolved similar physiological traits that allow sporadic metabolism during periods of increased water activity.« less
Neural correlates of humor detection and appreciation.
Moran, Joseph M; Wig, Gagan S; Adams, Reginald B; Janata, Petr; Kelley, William M
2004-03-01
Humor is a uniquely human quality whose neural substrates remain enigmatic. The present report combined dynamic, real-life content and event-related functional magnetic resonance imaging (fMRI) to dissociate humor detection ("getting the joke") from humor appreciation (the affective experience of mirth). During scanning, subjects viewed full-length episodes of the television sitcoms Seinfeld or The Simpsons. Brain activity time-locked to humor detection moments revealed increases in left inferior frontal and posterior temporal cortices, whereas brain activity time-locked to moments of humor appreciation revealed increases in bilateral regions of insular cortex and the amygdala. These findings provide evidence that humor depends critically upon extant neural systems important for resolving incongruities (humor detection) and for the expression of affect (humor appreciation).
Infrared dim target detection based on visual attention
NASA Astrophysics Data System (ADS)
Wang, Xin; Lv, Guofang; Xu, Lizhong
2012-11-01
Accurate and fast detection of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. Based on human visual attention mechanisms, an automatic detection algorithm for infrared dim target is presented. After analyzing the characteristics of infrared dim target images, the method firstly designs Difference of Gaussians (DoG) filters to compute the saliency map. Then the salient regions where the potential targets exist in are extracted by searching through the saliency map with a control mechanism of winner-take-all (WTA) competition and inhibition-of-return (IOR). At last, these regions are identified by the characteristics of the dim IR targets, so the true targets are detected, and the spurious objects are rejected. The experiments are performed for some real-life IR images, and the results prove that the proposed method has satisfying detection effectiveness and robustness. Meanwhile, it has high detection efficiency and can be used for real-time detection.
Reward and punishment learning in daily life: A replication study.
Heininga, Vera E; van Roekel, Eeske; Wichers, Marieke; Oldehinkel, Albertine J
2017-01-01
Day-to-day experiences are accompanied by feelings of Positive Affect (PA) and Negative Affect (NA). Implicitly, without conscious processing, individuals learn about the reward and punishment value of each context and activity. These associative learning processes, in turn, affect the probability that individuals will re-engage in such activities or seek out that context. So far, implicit learning processes are almost exclusively investigated in controlled laboratory settings and not in daily life. Here we aimed to replicate the first study that investigated implicit learning processes in real life, by means of the Experience Sampling Method (ESM). That is, using an experience-sampling study with 90 time points (three measurements over 30 days), we prospectively measured time spent in social company and amount of physical activity as well as PA and NA in the daily lives of 18-24-year-old young adults (n = 69 with anhedonia, n = 69 without anhedonia). Multilevel analyses showed a punishment learning effect with regard to time spent in company of friends, but not a reward learning effect. Neither reward nor punishment learning effects were found with regard to physical activity. Our study shows promising results for future research on implicit learning processes in daily life, with the proviso of careful consideration of the timescale used. Short-term retrospective ESM design with beeps approximately six hours apart may suffer from mismatch noise that hampers accurate detection of associative learning effects over time.
NASA Astrophysics Data System (ADS)
Bonaccorsi, R.; Stoker, C. R.
2005-12-01
The subsurface is the key environment for searching for life on planets lacking surface life. Subsurface ecosystems are of great relevance to astrobiology including the search for past/present life on Mars. The surface of Mars has conditions preventing current life but the subsurface might preserve organics and even host some life [1]. The Mars-Analog-Rio-Tinto-Experiment (MARTE) is performing a simulation of a Mars drilling experiment. This comprises conventional and robotic drilling of cores in a volcanically-hosted-massive-pyrite deposit [2] from the Iberian Pyritic Belt (IBP) and life detection experiments applying anti-contamination protocols (e.g., ATP Luminometry assay). The RT is considered an important analog of the Sinus Meridiani site on Mars and an ideal model analog for a deep subsurface Martian environment. Former results from MARTE suggest the existence of a relatively complex subsurface life including aerobic and anaerobic chemoautotrophs and strict anaerobic methanogens sustained by Fe and S minerals in anoxic conditions. A key requirement for the analysis of a subsurface sample on Mars is a set of simple tests that can help determine if the sample contains organic material of biological origin, and its potential for retaining definitive biosignatures. We report here on the presence of bulk organic matter Corg (0.03-0.05 Wt%), and Ntot (0.01-0.04 Wt%) and amount of measured ATP (Lightning MVP, Biocontrol) in weathered rocks (tuffs, gossan, pyrite stockwork from Borehole #8; >166m). This provides key insight on the type of trophic system sustaining the subsurface biosphere (i.e., heterotrophs vs. autotrophs) at RT. ATP data (Relative-Luminosity-Units, RLU) provide information on possible contamination and distribution of viable biomass with core depth (BH#8, and BH#7, ~3m). Avg. 153 RLU, i.e., surface vs. center of core, suggest that cleaness/sterility can be maintained when using a simple sterile protocol under field conditions. Results from this research will support future drilling mission planned on Mars. [1] Boston, P.J., et al., 1992. Icarus 95,300-308; [2] Leistel et al., 1998.
EEG seizure detection and prediction algorithms: a survey
NASA Astrophysics Data System (ADS)
Alotaiby, Turkey N.; Alshebeili, Saleh A.; Alshawi, Tariq; Ahmad, Ishtiaq; Abd El-Samie, Fathi E.
2014-12-01
Epilepsy patients experience challenges in daily life due to precautions they have to take in order to cope with this condition. When a seizure occurs, it might cause injuries or endanger the life of the patients or others, especially when they are using heavy machinery, e.g., deriving cars. Studies of epilepsy often rely on electroencephalogram (EEG) signals in order to analyze the behavior of the brain during seizures. Locating the seizure period in EEG recordings manually is difficult and time consuming; one often needs to skim through tens or even hundreds of hours of EEG recordings. Therefore, automatic detection of such an activity is of great importance. Another potential usage of EEG signal analysis is in the prediction of epileptic activities before they occur, as this will enable the patients (and caregivers) to take appropriate precautions. In this paper, we first present an overview of seizure detection and prediction problem and provide insights on the challenges in this area. Second, we cover some of the state-of-the-art seizure detection and prediction algorithms and provide comparison between these algorithms. Finally, we conclude with future research directions and open problems in this topic.
Mannion, Damien J; Donkin, Chris; Whitford, Thomas J
2017-01-01
We investigated the relationship between psychometrically-defined schizotypy and the ability to detect a visual target pattern. Target detection is typically impaired by a surrounding pattern (context) with an orientation that is parallel to the target, relative to a surrounding pattern with an orientation that is orthogonal to the target (orientation-dependent contextual modulation). Based on reports that this effect is reduced in those with schizophrenia, we hypothesised that there would be a negative relationship between the relative score on psychometrically-defined schizotypy and the relative effect of orientation-dependent contextual modulation. We measured visual contrast detection thresholds and scores on the Oxford-Liverpool Inventory of Feelings and Experiences (O-LIFE) from a non-clinical sample ( N = 100). Contrary to our hypothesis, we find an absence of a monotonic relationship between the relative magnitude of orientation-dependent contextual modulation of visual contrast detection and the relative score on any of the subscales of the O-LIFE. The apparent difference of this result with previous reports on those with schizophrenia suggests that orientation-dependent contextual modulation may be an informative condition in which schizophrenia and psychometrically-defined schizotypy are dissociated. However, further research is also required to clarify the strength of orientation-dependent contextual modulation in those with schizophrenia.
Optimizing Probability of Detection Point Estimate Demonstration
NASA Technical Reports Server (NTRS)
Koshti, Ajay M.
2017-01-01
Probability of detection (POD) analysis is used in assessing reliably detectable flaw size in nondestructive evaluation (NDE). MIL-HDBK-18231and associated mh18232POD software gives most common methods of POD analysis. Real flaws such as cracks and crack-like flaws are desired to be detected using these NDE methods. A reliably detectable crack size is required for safe life analysis of fracture critical parts. The paper provides discussion on optimizing probability of detection (POD) demonstration experiments using Point Estimate Method. POD Point estimate method is used by NASA for qualifying special NDE procedures. The point estimate method uses binomial distribution for probability density. Normally, a set of 29 flaws of same size within some tolerance are used in the demonstration. The optimization is performed to provide acceptable value for probability of passing demonstration (PPD) and achieving acceptable value for probability of false (POF) calls while keeping the flaw sizes in the set as small as possible.
Derveni, Mariliza; Hands, Alex; Allen, Marjorie; Sims, Mark R; Cullen, David C
2012-08-01
The Life Marker Chip (LMC) instrument is part of the proposed payload on the ESA ExoMars rover that is scheduled for launch in 2018. The LMC will use antibody-based assays to detect molecular signatures of life in samples obtained from the shallow subsurface of Mars. For the LMC antibodies, the ability to resist inactivation due to space particle radiation (both in transit and on the surface of Mars) will therefore be a prerequisite. The proton and neutron components of the mission radiation environment are those that are expected to have the dominant effect on the operation of the LMC. Modeling of the radiation environment for a mission to Mars led to the calculation of nominal mission fluences for proton and neutron radiation. Various combinations and multiples of these values were used to demonstrate the effects of radiation on antibody activity, primarily at the radiation levels envisaged for the ExoMars mission as well as at much higher levels. Five antibodies were freeze-dried in a variety of protective molecular matrices and were exposed to various radiation conditions generated at a cyclotron facility. After exposure, the antibodies' ability to bind to their respective antigens was assessed and found to be unaffected by ExoMars mission level radiation doses. These experiments indicated that the expected radiation environment of a Mars mission does not pose a significant risk to antibodies packaged in the form anticipated for the LMC instrument.
Spectral-spatial classification for noninvasive cancer detection using hyperspectral imaging
NASA Astrophysics Data System (ADS)
Lu, Guolan; Halig, Luma; Wang, Dongsheng; Qin, Xulei; Chen, Zhuo Georgia; Fei, Baowei
2014-10-01
Early detection of malignant lesions could improve both survival and quality of life of cancer patients. Hyperspectral imaging (HSI) has emerged as a powerful tool for noninvasive cancer detection and diagnosis, with the advantage of avoiding tissue biopsy and providing diagnostic signatures without the need of a contrast agent in real time. We developed a spectral-spatial classification method to distinguish cancer from normal tissue on hyperspectral images. We acquire hyperspectral reflectance images from 450 to 900 nm with a 2-nm increment from tumor-bearing mice. In our animal experiments, the HSI and classification method achieved a sensitivity of 93.7% and a specificity of 91.3%. The preliminary study demonstrated that HSI has the potential to be applied in vivo for noninvasive detection of tumors.
Near-infrared tunable laser diode spectroscopy: an easy way for gas sensing
NASA Astrophysics Data System (ADS)
Larive, Marc; Henriot, V.
1997-05-01
A gas sensor using optical spectrometry and dedicated to a specific gas is studied. It should be able to operate out of laboratories with a very long life and a low maintenance requirement. It is based on TLDS (tunable laser diode spectroscopy) and uses a standard Perot-Fabry laser diode already developed for telecommunications. The mode selection is realized by a passband filter and the wavelength tuning is performed via the diode temperature or its injection current. A PIN photodiode is used for detection, however a rough photoacoustic solution is intended for the future. Absorptions as low as 3.10-3 are detected with this rough system and a limit detection of 10-3 is available with a signal to noise ratio of unity. Experiments have shown that this system is strongly selective for the specified gas (currently the methane). A simulation has been performed which very well fits the experiment and allows us to extrapolate the performances of the system for other gases.
NASA and the search for life in the universe.
Dick, Steven J
2006-06-01
Almost from its beginnings in 1958, the National Aeronautics and Space Administration (NASA) set up a life-science program. Because one of the priorities of the organization is to search for life beyond Earth, NASA began designing spacecraft to unravel the mysteries of Mars. The effort to search for life on Mars culminated in the landing of two Viking spacecraft on the surface of the planet in 1976. Although the biology experiments conducted as part of these missions provided some evidence for the possibility of life, the scientific consensus was that they drew a blank. In 1996, however, the 'Mars rock' rekindled interest in life in our solar system. The discovery of an ocean on the Jovian moon Europa, of organic molecules on the Saturnian moon Titan and persuasive evidence that water once flowed on Mars suggests that the solar system is still of considerable exobiological interest. In addition, since 1995 approximately 175 planets have been found beyond our solar system. Although these discoveries are gas giants, NASA spacecraft might soon detect Earth-sized planets. The search for life in the universe continues.
Exposure to a mildly aversive early life experience leads to prefrontal cortex deficits in the rat.
Stamatakis, Antonios; Manatos, Vasileios; Kalpachidou, Theodora; Stylianopoulou, Fotini
2016-11-01
Aversive early life experiences in humans have been shown to result in deficits in the function of the prefrontal cortex (PFC). In an effort to elucidate possible neurobiological mechanisms involved, we investigated in rats, the effects of a mildly aversive early experience on PFC structure and function. The early experience involved exposure of rat pups during postnatal days (PND) 10-13 to a T-maze in which they search for their mother, but upon finding her are prohibited contact with her, thus being denied the expected reward (DER). We found that the DER experience resulted in adulthood in impaired PFC function, as assessed by two PFC-dependent behavioral tests [attention set-shifting task (ASST) and fear extinction]. In the ASST, DER animals showed deficits specifically in the intra-dimensional reversal shifts and a lower activation-as determined by c-Fos immunohistochemistry-of the medial orbital cortex (MO), a PFC subregion involved in this aspect of the task. Furthermore, the DER experience resulted in decreased glutamatergic neuron and dendritic spine density in the MO and infralimbic cortex (IL) in the adult brain. The decreased neuronal density was detected as early as PND12 and was accompanied by increased micro- and astroglia-density in the MO/IL.
NASA Technical Reports Server (NTRS)
Allen, C. C.; Wainwright, N. R.; Grasby, S. E.; Harvey, R. P.
2003-01-01
The current Martian surface environment is extremely hostile to any known form of life. The combination of subfreezing temperature, low atmospheric pressure and high ultraviolet flux, combined with desiccated and possibly oxidizing soil, could destroy even the hardiest microorganisms. The Viking biology experiments are generally interpreted to indicate that the surface of Mars is currently devoid of life and organic molecules at the part-per-billion level. Speculation on the possibility of extant or preserved microbial life on Mars thus centers on refuges in some manner protected from the current surface environment, either in space or time. Terrestrial analogs include hydrothermal systems, lakes, caves and subsurface aquifers as well as more clement conditions in the distant past. We are examining the evidence for microbiology in Earth's glaciated polar regions as analogs to the polar caps of Mars. This research concerns the detection of microorganisms or their preserved remains at the surface and within polar glacial ice.
Forward Contamination of the Moon and Mars: Implications for Future Life Detection Missions
NASA Technical Reports Server (NTRS)
Glavin, Daniel P.; Dworkin, Jason P.; Lupisella, Mark; Kminek, Gerhard; Rummel, John D.
2004-01-01
NASA and ESA have outlined new visions for solar system exploration that will include a series of lunar robotic missions to prepare for, and support a human return to the Moon, and future human exploration of Mars and other destinations. One of the guiding principles for exploration is to pursue compelling scientific questions about the origin and evolution of life. The search for life on objects such as Mars will require that all spacecraft and instrumentation be sufficiently cleaned and sterilized prior to launch to ensure that the scientific integrity of extraterrestrial samples is not jeopardized by terrestrial organic contamination. Under COSPAR's current planetary protection policy for the Moon, no sterilization procedures are required for outbound lunar spacecraft. Nonetheless, future in situ investigations of a variety of locations on the Moon by highly sensitive instruments designed to search for biologically derived organic compounds would help assess the contamination of the Moon by lunar spacecraft. These studies could also provide valuable "ground truth" data for Mars sample return missions and help define planetary protection requirements for future Mars bound spacecraft carrying life detection experiments. In addition, studies of the impact of terrestrial contamination of the lunar surface by the Apollo astronauts could provide valuable data to help refine future Mars surface exploration plans for a human mission to Mars.
NASA Astrophysics Data System (ADS)
Stan-Lotter, Helga; Fendrihan, Sergiu; Dornmayr-Pfaffenhuemer, Marion; Holzinger, Anita; Polacsek, Tatjana K.; Legat, Andrea; Grösbacher, Michael; Weigl, Andreas
2010-05-01
Background: The search for extraterrestrial life has been declared as a goal for the 21th century by several space agencies. Potential candidates are microorganisms on or in the surface of moons and planets, such as Mars. Extremely halophilic archaea (haloarchaea) are of astrobiological interest since viable strains have been isolated from million years old salt deposits (1) and halite has been found in Martian meteorites and in surface pools. Therefore, haloarchaeal responses to simulated and real space conditions were explored. Immuno assays for a potential Life Marker Chip experiment were developed with antisera against the universal enzyme ATP synthase. Methods: The focus of these studies was on the application of fluorescent probes since they provide strong signals, and detection devices are suitable for miniaturization. Viability of haloarchaeal strains (Halococcus dombrowskii and Halobacterium salinarum NRC-1) was probed with the LIVE/DEAD BacLight™ kit and the BacLight™ Bacterial Membrane Potential kit. Cyclobutane pyrimidine dimers (CPD) in the DNA, following exposure to simulated and real space conditions (UV irradiation from 200 - 400 nm; 18 months exposure on the International Space Station [ISS] within the ADAPT experiment by Dr. P. Rettberg), were detected with fluorescent Alexa-Fluor-488-coupled antibodies. Immuno assays with antisera against the A-ATPase subunits from Halorubrum saccharovorum were carried out with the highly sensitive Immun-Star ™ WesternC ™ chemiluminescent kit (Bio-Rad). Results: Using the LIVE/DEAD BacLight™ kit, the D37 (dose of 37% survival) for Hcc. dombrowskii and Hbt. salinarum NRC-1, following exposure to UV (200-400 nm) was about 400 kJ/m2, when cells were embedded in halite and about 1 kJ/m2, when cells were in liquid cultures. Fluorescent staining indicated a slightly higher cellular activity than that which was derived from the determination of colony forming units. Assessment of viability with the BacLight™ Bacterial Membrane Potential kit gave strong signals with Hcc. dombrowskii and the control microorganism E. coli; as expected, the uncoupler CCCP diminished the membrane potential. Reaction times were generally longer with Hcc. dombrowskii than with E. coli. Hcc. dombrowskii from the ISS experiment showed > 80% viable cells when judged with the LIVE/DEAD kit. CPD formation was detectable in about 3-5 % of the total cells. It is not yet known if growing cells of Hcc. dombrowskii were recovered from the ISS. ATPase subunits were detected in crude membrane preparations, in whole haloarchaeal and bacterial cells, and even in spores (from Geobacillus stearothermophilus), suggesting the usefulness of the ATP synthase as a molecular target for life detection. Conclusions: Fluorescent dyes provide strong signals, which are suitable for remote detection and are compatible with high ionic strength. The advantages of staining with fluorescent dyes are rapid results on membrane intactness, membrane potential, and the presence of certain biomolecules. But more data are needed for a better correlation to cellular viability. (1) Stan-Lotter H, Pfaffenhuemer M, Legat A, Busse H-J, Radax C, Gruber C (2002) Halococcus dombrowskii sp. nov., an archaeal isolate from a Permian alpine salt deposit. Int System Evol Microbiol 52, 1807-1814.
Life science experiments performed in space in the ISS/Kibo facility and future research plans.
Ohnishi, Takeo
2016-08-01
Over the past several years, current techniques in molecular biology have been used to perform experiments in space, focusing on the nature and effects of space radiation. In the Japanese 'Kibo' facility in the International Space Station (ISS), the Japan Aerospace Exploration Agency (JAXA) has performed five life science experiments since 2009, and two additional experiments are currently in progress. The first life science experiment in space was the 'Rad Gene' project, which utilized two human cultured lymphoblastoid cell lines containing a mutated P53 : gene (m P53 : ) and a parental wild-type P53 : gene (wt P53 : ) respectively. Four parameters were examined: (i) detecting space radiation-induced DSBs by observing γH2AX foci; (ii) observing P53 : -dependent gene expression during space flight; (iii) observing P53 : -dependent gene expression after space flight; and (iv) observing the adaptive response in the two cell lines containing the mutated and wild type P53 : genes after exposure to space radiation. These observations were completed and have been reported, and this paper is a review of these experiments. In addition, recent new information from space-based experiments involving radiation biology is presented here. These experiments involve human cultured cells, silkworm eggs, mouse embryonic stem cells and mouse eggs in various experiments designed by other principal investigators in the ISS/Kibo. The progress of Japanese science groups involved in these space experiments together with JAXA are also discussed here. The Japanese Society for Biological Sciences in Space (JSBSS), the Utilization Committee of Space Environment Science (UCSES) and the Science Council of Japan (ACJ) have supported these new projects and new experimental facilities in ISS/Kibo. Currently, these organizations are proposing new experiments for the ISS through 2024. © The Author 2016. Published by Oxford University Press on behalf of The Japan Radiation Research Society and Japanese Society for Radiation Oncology.
Macías-Chapula, C A
1987-01-01
Indicators, variables and barriers to scientific and technical health information have been detected and described by CENIDS in Mexico within the life cycle of the information production model, covering the phases of: a) generation; b) institutionalization; c) maintenance/development; and d) distribution/dissemination. Emphasis is placed on the important role that play social, economic, demographic, and political factors of each developing country to conform their ideal information life cycle. After an analysis of the existing Mexican situation, and a short description of CENIDS' structure, organization, functions and services, CENIDS' short-term and mid-term projects, and suggestions for further research lines to improve the current situation in Mexico are also given.
Simmonds, Peter G.
1970-01-01
Pyrolysis-gas chromatography-mass spectrometric studies of two microorganisms, Micrococcus luteus and Bacillus subtilis var. niger, indicate that the majority of thermal fragments originate from the principal classes of bio-organic matter found in living systems such as protein and carbohydrate. Furthermore, there is a close qualitative similarity between the type of pyrolysis products found in microorganisms and the pyrolysates of other biological materials. Conversely, there is very little correlation between microbial pyrolysates and comparable pyrolysis studies of meteoritic and fossil organic matter. These observations will aid in the interpretation of a soil organic analysis experiment to be performed on the surface of Mars in 1975. The science payload of this landed mission will include a combined pyrolysis-gas chromatography-mass spectrometry instrument as well as several “direct biology experiments” which are designed to search for extraterrestrial life. PMID:16349890
Viking labeled release biology experiment - Interim results
NASA Technical Reports Server (NTRS)
Levin, G. V.; Straat, P. A.
1976-01-01
All results of the labeled-release life-detection experiment conducted on Mars prior to conjunction are summarized. Tests at both landing sites provide remarkably similar evolution of radioactive gas upon addition of a radioactive nutrient to the Mars sample. The 'active' agent in the sample is stable to 18 C, but is substantially inactivated by heat treatment for 3 hours at 50 C and completely inactivated at 160 C, as would be anticipated if the active response were caused by microorganisms. Results from test and heat-sterilized control samples are compared with those obtained from terrestrial soils and a lunar sample. Possible nonbiological explanations of the Mars data are reviewed. Although such explanations of the labeled-release data depend on UV irradiation, the labeled-release response does not appear to depend on recent direct UV activation of surface material. Available facts do not yet permit a conclusion regarding the existence of life on Mars.
Reward and punishment learning in daily life: A replication study
van Roekel, Eeske; Wichers, Marieke; Oldehinkel, Albertine J.
2017-01-01
Day-to-day experiences are accompanied by feelings of Positive Affect (PA) and Negative Affect (NA). Implicitly, without conscious processing, individuals learn about the reward and punishment value of each context and activity. These associative learning processes, in turn, affect the probability that individuals will re-engage in such activities or seek out that context. So far, implicit learning processes are almost exclusively investigated in controlled laboratory settings and not in daily life. Here we aimed to replicate the first study that investigated implicit learning processes in real life, by means of the Experience Sampling Method (ESM). That is, using an experience-sampling study with 90 time points (three measurements over 30 days), we prospectively measured time spent in social company and amount of physical activity as well as PA and NA in the daily lives of 18-24-year-old young adults (n = 69 with anhedonia, n = 69 without anhedonia). Multilevel analyses showed a punishment learning effect with regard to time spent in company of friends, but not a reward learning effect. Neither reward nor punishment learning effects were found with regard to physical activity. Our study shows promising results for future research on implicit learning processes in daily life, with the proviso of careful consideration of the timescale used. Short-term retrospective ESM design with beeps approximately six hours apart may suffer from mismatch noise that hampers accurate detection of associative learning effects over time. PMID:28976985
NASA Astrophysics Data System (ADS)
Sugino, Tomohiro; Yokobori, Shin-Ichi; Yang, Yinjie; Kawaguchi, Yuko; Okudaira, Kyoko; Tabata, Makoto; Kawai, Hideyuki; Hasegawa, Sunao; Yamagishi, Akihiko
Microbes have been collected at the altitude up to about 70 km in the sampling experiment done by several groups[1]. We have also collected high altitude microbes, by using an airplane and balloons[2][3][4][5]. We collected new deinococcal strain (Deinococcus aetherius and Deinococ-cus aerius) and several strains of spore-forming bacilli from stratosphere[2][4][5]. However, microbe sampling in space has never been reported. On the other hand, "Panspermia" hy-pothesis, where terrestrial life is originated from outside of Earth, has been proposed[6][7][8][9]. Recent report suggesting existence of the possible microbe fossils in the meteorite of Mars origin opened the serious debate on the possibility of migration of life embedded in meteorites (and cosmic dusts)[10][11]. If we were able to find terrestrial microbes in space, it would suggest that the terrestrial life can travel between astronomical bodies. We proposed a mission "Tanpopo: Astrobiology Exposure and Micrometeoroid Capture Experiments" to examine possible inter-planetary migration of microbes, organic compounds and meteoroids on Japan Experimental Module of the International Space Station (ISS)[12]. Two of six sub themes in this mission are directly related to interplanetary migration of microbes. One is the direct capturing experi-ment of microbes (probably within the particles such as clay) in space by the exposed ultra-low density aerogel. Another is the exposure experiment to examine survivability of the microbes in harsh space environment. They will tell us the possibility of interplanetary migration of microbes (life) from Earth to outside of Earth (or vise versa). In this report, we will report whether aerogel that have been used for the collection of space debris and cosmic dusts can be used for microbe sampling in space. We will discuss how captured particles by aerogel can be detected with DNA-specific fluorescent dye, and how to distinguish microbes from other mate-rials (i.e. aerogel and particles such as clay). The surface of micro-particles captured by aerogel is often vitrified. The non-specific fluorescent light is often observed from vitrified materials. Therefore, we need to distinguish fluorescent light of stained microbes from that of vitrified ma-terials. We are going to use two types of differences (wavelength dependence and attenuation rate of fluorescent) between stained microbes with DNA-specific fluorescent dye and other ma-terials such as clay and aerogel. Fluorescent light of stained microbes shows attenuation faster than that of vitrified materials. Fluorescent light of vitrified materials shows broader range of emission spectra than that of stained microbes. In addition, we simulated the high-speed collision experiment of micro-particles to the aerogel with the two stage light gas gun (ca. 4 km/s). The micro-particles containing pre-stained and dried cells of Deinococcus radiodurans mixed with clay material were used for the collision experiment, and the captured particles were observed with fluorescence microscope. This experiment suggests that the captured microbes can be detected and be distinguished from clay materials. Reference [1] Yang, Y. et al. (2009) Biol. Sci. Space, 23, 151-163. [2] Yang, Y., et al. (2008) Biol. Sci. Space 22:18-25. [3] Yang, Y., et al. (2008) JAXA-RR-08-001: 34-42. [4] Yang, Y., et al. (2009) Internatl. J. Syst. Evol. Bacteriol., 59: 1862-1866. [5] Yang, Y. et al. (2010) Internatl. J. Syst. Evol. Bacteriol. (in press). [6] Arrhenius, S. (1908) Worlds in the Making-the Evolution of the Universe (translation to English by H. Borns) Harper and Brothers Publishers, New York. [7]Crick, F. (1981) Life Itself. Simon Schuster, New York. [8] W.L. Nicholson et al., Microbiol. Mol. Biol. Rev. 64 (2000) 548. [9] G. Horneck et al., Orig. Life Evol. Biosph. 31 (2001) 527. [10] Chyba, C. and C. Sagan (1992) Nature 355: 125-132. [11] Sandford, S. A., et al. (2006) Science 314: 1720-1724. [12] Yamagishi, A., et al. (2008) International Symposium on Space Technology and Science (ISTS) Web Paper Archives. 2008-k-05.
NASA Astrophysics Data System (ADS)
Wohland, Thorsten
2015-06-01
Single Molecule Detection and Spectroscopy have grown from their first beginnings into mainstream, mature research areas that are widely applied in the biological sciences. However, despite the advances in technology and the application of many single molecule techniques even in in vivo settings, the data analysis of single molecule experiments is complicated by noise, systematic errors, and complex underlying processes that are only incompletely understood. Colomb and Sarkar provide in this issue an overview of single molecule experiments and the accompanying problems in data analysis, which have to be overcome for a proper interpretation of the experiments [1].
Statistics of software vulnerability detection in certification testing
NASA Astrophysics Data System (ADS)
Barabanov, A. V.; Markov, A. S.; Tsirlov, V. L.
2018-05-01
The paper discusses practical aspects of introduction of the methods to detect software vulnerability in the day-to-day activities of the accredited testing laboratory. It presents the approval results of the vulnerability detection methods as part of the study of the open source software and the software that is a test object of the certification tests under information security requirements, including software for communication networks. Results of the study showing the allocation of identified vulnerabilities by types of attacks, country of origin, programming languages used in the development, methods for detecting vulnerability, etc. are given. The experience of foreign information security certification systems related to the detection of certified software vulnerabilities is analyzed. The main conclusion based on the study is the need to implement practices for developing secure software in the development life cycle processes. The conclusions and recommendations for the testing laboratories on the implementation of the vulnerability analysis methods are laid down.
Interference and deception detection technology of satellite navigation based on deep learning
NASA Astrophysics Data System (ADS)
Chen, Weiyi; Deng, Pingke; Qu, Yi; Zhang, Xiaoguang; Li, Yaping
2017-10-01
Satellite navigation system plays an important role in people's daily life and war. The strategic position of satellite navigation system is prominent, so it is very important to ensure that the satellite navigation system is not disturbed or destroyed. It is a critical means to detect the jamming signal to avoid the accident in a navigation system. At present, the detection technology of jamming signal in satellite navigation system is not intelligent , mainly relying on artificial decision and experience. For this issue, the paper proposes a method based on deep learning to monitor the interference source in a satellite navigation. By training the interference signal data, and extracting the features of the interference signal, the detection sys tem model is constructed. The simulation results show that, the detection accuracy of our detection system can reach nearly 70%. The method in our paper provides a new idea for the research on intelligent detection of interference and deception signal in a satellite navigation system.
Remote sensing of life: polarimetric signatures of photosynthetic pigments as sensitive biomarkers
NASA Astrophysics Data System (ADS)
Berdyugina, Svetlana V.; Kuhn, Jeff R.; Harrington, David M.; Šantl-Temkiv, Tina; Messersmith, E. John
2016-01-01
We develop a polarimetry-based remote-sensing method for detecting and identifying life forms in distant worlds and distinguishing them from non-biological species. To achieve this we have designed and built a bio-polarimetric laboratory experiment BioPol for measuring optical polarized spectra of various biological and non-biological samples. Here we focus on biological pigments, which are common in plants and bacteria that employ them either for photosynthesis or for protection against reactive oxygen species. Photosynthesis, which provides organisms with the ability to use light as a source of energy, emerged early in the evolution of life on Earth. The ability to harvest such a significant energy resource could likely also develop on habited exoplanets. Thus, we investigate the detectability of biomolecules that can capture photons of particular wavelengths and contribute to storing their energy in chemical bonds. We have carried out laboratory spectropolarimetric measurements of a representative sample of plants containing various amounts of pigments such as chlorophyll, carotenoids and others. We have also measured a variety of non-biological samples (sands, rocks). Using our lab measurements, we have modelled intensity and polarized spectra of Earth-like planets having different surface coverage by photosynthetic organisms, deserted land and ocean, as well as clouds. Our results demonstrate that linearly polarized spectra provide very sensitive and rather unambiguous detection of photosynthetic pigments of various kinds. Our work paves the path towards analogous measurements of microorganisms and remote sensing of microbial ecology on the Earth and of extraterrestrial life on other planets and moons.
Freissinet, C; Buch, A; Sternberg, R; Szopa, C; Geffroy-Rodier, C; Jelinek, C; Stambouli, M
2010-01-29
Within the context of the future space missions to Mars (MSL 2011 and Exomars 2016), which aim at searching for traces of life at the surface, the detection and quantitation of enantiomeric organic molecules is of major importance. In this work, we have developed and optimized a method to derivatize and analyze chiral organic molecules suitable for space experiments, using N,N-dimethylformamide dimethylacetal (DMF-DMA) as the derivatization agent. The temperature, duration of the derivatization reaction, and chromatographic separation parameters have been optimized to meet instrument design constraints imposed upon space experiment devices. This work demonstrates that, in addition to its intrinsic qualities, such as production of light-weight derivatives and a great resistance to drastic operating conditions, DMF-DMA facilitates simple and fast derivatization of organic compounds (three minutes at 140 degrees C in a single-step) that is suitable for an in situ analysis in space. By using DMF-DMA as the derivatization agent, we have successfully identified 19 of the 20 proteinic amino acids and been able to enantiomerically separate ten of the potential 19 (glycine being non-chiral). Additionally, we have minimized the percentage of racemized amino acid compounds produced by optimizing the conditions of the derivatization reaction itself. Quantitative linearity studies and the determination of the limit of detection show that the proposed method is also suitable for the quantitative determination of both enantiomeric forms of most of the tested amino acids, as limits of detection obtained are lower than the ppb level of organic molecules already detected in Martian meteorites. Copyright (c) 2009 Elsevier B.V. All rights reserved.
Detection of cardiac activity changes from human speech
NASA Astrophysics Data System (ADS)
Tovarek, Jaromir; Partila, Pavol; Voznak, Miroslav; Mikulec, Martin; Mehic, Miralem
2015-05-01
Impact of changes in blood pressure and pulse from human speech is disclosed in this article. The symptoms of increased physical activity are pulse, systolic and diastolic pressure. There are many methods of measuring and indicating these parameters. The measurements must be carried out using devices which are not used in everyday life. In most cases, the measurement of blood pressure and pulse following health problems or other adverse feelings. Nowadays, research teams are trying to design and implement modern methods in ordinary human activities. The main objective of the proposal is to reduce the delay between detecting the adverse pressure and to the mentioned warning signs and feelings. Common and frequent activity of man is speaking, while it is known that the function of the vocal tract can be affected by the change in heart activity. Therefore, it can be a useful parameter for detecting physiological changes. A method for detecting human physiological changes by speech processing and artificial neural network classification is described in this article. The pulse and blood pressure changes was induced by physical exercises in this experiment. The set of measured subjects was formed by ten healthy volunteers of both sexes. None of the subjects was a professional athlete. The process of the experiment was divided into phases before, during and after physical training. Pulse, systolic, diastolic pressure was measured and voice activity was recorded after each of them. The results of this experiment describe a method for detecting increased cardiac activity from human speech using artificial neural network.
Testing the H2O2-H2O hypothesis for life on Mars with the TEGA instrument on the Phoenix lander.
Schulze-Makuch, Dirk; Turse, Carol; Houtkooper, Joop M; McKay, Christopher P
2008-04-01
In the time since the Viking life-detection experiments were conducted on Mars, many missions have enhanced our knowledge about the environmental conditions on the Red Planet. However, the martian surface chemistry and the Viking lander results remain puzzling. Nonbiological explanations that favor a strong inorganic oxidant are currently favored (e.g., Mancinelli, 1989; Plumb et al., 1989; Quinn and Zent, 1999; Klein, 1999; Yen et al., 2000), but problems remain regarding the lifetime, source, and abundance of that oxidant to account for the Viking observations (Zent and McKay, 1994). Alternatively, a hypothesis that favors the biological origin of a strong oxidizer has recently been advanced (Houtkooper and Schulze-Makuch, 2007). Here, we report on laboratory experiments that simulate the experiments to be conducted by the Thermal and Evolved Gas Analyzer (TEGA) instrument of the Phoenix lander, which is to descend on Mars in May 2008. Our experiments provide a baseline for an unbiased test for chemical versus biological responses, which can be applied at the time the Phoenix lander transmits its first results from the martian surface.
Preliminary design of the redundant software experiment
NASA Technical Reports Server (NTRS)
Campbell, Roy; Deimel, Lionel; Eckhardt, Dave, Jr.; Kelly, John; Knight, John; Lauterbach, Linda; Lee, Larry; Mcallister, Dave; Mchugh, John
1985-01-01
The goal of the present experiment is to characterize the fault distributions of highly reliable software replicates, constructed using techniques and environments which are similar to those used in comtemporary industrial software facilities. The fault distributions and their effect on the reliability of fault tolerant configurations of the software will be determined through extensive life testing of the replicates against carefully constructed randomly generated test data. Each detected error will be carefully analyzed to provide insight in to their nature and cause. A direct objective is to develop techniques for reducing the intensity of coincident errors, thus increasing the reliability gain which can be achieved with fault tolerance. Data on the reliability gains realized, and the cost of the fault tolerant configurations can be used to design a companion experiment to determine the cost effectiveness of the fault tolerant strategy. Finally, the data and analysis produced by this experiment will be valuable to the software engineering community as a whole because it will provide a useful insight into the nature and cause of hard to find, subtle faults which escape standard software engineering validation techniques and thus persist far into the software life cycle.
Karkar, Ravi; Schroeder, Jessica; Epstein, Daniel A; Pina, Laura R; Scofield, Jeffrey; Fogarty, James; Kientz, Julie A; Munson, Sean A; Vilardaga, Roger; Zia, Jasmine
2017-05-02
Diagnostic self-tracking, the recording of personal information to diagnose or manage a health condition, is a common practice, especially for people with chronic conditions. Unfortunately, many who attempt diagnostic self-tracking have trouble accomplishing their goals. People often lack knowledge and skills needed to design and conduct scientifically rigorous experiments, and current tools provide little support. To address these shortcomings and explore opportunities for diagnostic self-tracking, we designed, developed, and evaluated a mobile app that applies a self-experimentation framework to support patients suffering from irritable bowel syndrome (IBS) in identifying their personal food triggers. TummyTrials aids a person in designing, executing, and analyzing self-experiments to evaluate whether a specific food triggers their symptoms. We examined the feasibility of this approach in a field study with 15 IBS patients, finding that participants could use the tool to reliably undergo a self-experiment. However, we also discovered an underlying tension between scientific validity and the lived experience of self-experimentation. We discuss challenges of applying clinical research methods in everyday life, motivating a need for the design of self-experimentation systems to balance rigor with the uncertainties of everyday life.
Sulfate minerals: a problem for the detection of organic compounds on Mars?
Lewis, James M T; Watson, Jonathan S; Najorka, Jens; Luong, Duy; Sephton, Mark A
2015-03-01
The search for in situ organic matter on Mars involves encounters with minerals and requires an understanding of their influence on lander and rover experiments. Inorganic host materials can be helpful by aiding the preservation of organic compounds or unhelpful by causing the destruction of organic matter during thermal extraction steps. Perchlorates are recognized as confounding minerals for thermal degradation studies. On heating, perchlorates can decompose to produce oxygen, which then oxidizes organic matter. Other common minerals on Mars, such as sulfates, may also produce oxygen upon thermal decay, presenting an additional complication. Different sulfate species decompose within a large range of temperatures. We performed a series of experiments on a sample containing the ferric sulfate jarosite. The sulfate ions within jarosite break down from 500 °C. Carbon dioxide detected during heating of the sample was attributed to oxidation of organic matter. A laboratory standard of ferric sulfate hydrate released sulfur dioxide from 550 °C, and an oxygen peak was detected in the products. Calcium sulfate did not decompose below 1000 °C. Oxygen released from sulfate minerals may have already affected organic compound detection during in situ thermal experiments on Mars missions. A combination of preliminary mineralogical analyses and suitably selected pyrolysis temperatures may increase future success in the search for past or present life on Mars.
NASA Astrophysics Data System (ADS)
Shepherd, Douglas
2015-06-01
Understanding how a population acts based on the collective actions of individuals is a long-standing challenge across all scientific fields. Over the last twenty years, a revolution in the detection of individual fluorescent molecules has brought together scientists from multiple fields, particularly with respect to imaging applications in cellular and microbiology [1-3]. Recently, new techniques have paved the way for sub-diffraction limit imaging of biological regulation in fixed and live cells, generating a wealth of new data [4-9]. However, this explosion in our ability to generate information on biology at the single-molecule level has so far outpaced our ability to robustly analyze, test, and understand what these experiments are actually reporting [10-12]. Because there are many sources of noise in these experiments, ranging from instrumental to stochastic chemical reactions, it is important to understand each source of noise and how to utilize it. In this sense, there is information in all the fluctuations that occur in these experiments.
NASA Astrophysics Data System (ADS)
Levin, Gilbert V.
2006-08-01
July 30, 2006 was the 30 th anniversary of the Viking Mission's first Labeled Release (LR) life detection experiment on Mars. The strong response, together with supporting results from eight additional LR tests of Martian soil, established the presence of an active agent that was inhibited by heating. The data satisfied the pre-mission criteria for the detection of living microorganisms. However, the scientific community reacted cautiously, generally concluding that the activity in the soil was caused by chemistry or physics. Over the last three decades, investigation of Mars has greatly increased. Soil, rock and atmospheric analyses have been made. Multi-spectral observations have been made from Mars and Earth orbits and from Earth-based telescopes. Knowledge of extreme habitats and bizarre life forms that populate them on Earth has increased dramatically. However, this vast amount of new astrobiological information has yet to be integrated into an objective scientific evaluation of the LR results and the possibilities for life on Mars. Indeed, in part upon misinterpretations of the new findings, myths have been embedded into the scientific literature of Mars. Based on these myths as key ingredients, a false "standard model" of Martian life potential has been developed. It has been accepted by much of the astrobiological community, and, through its endorsement, the world at large. This paper attempts to bring the supportable facts together in calling for a revision of the current consensus regarding life on Mars. It recommends actions to facilitate the paradigm change.
Leuko, Stefan; Bohmeier, Maria; Hanke, Franziska; Böettger, Ute; Rabbow, Elke; Parpart, Andre; Rettberg, Petra; de Vera, Jean-Pierre P.
2017-01-01
Outer space, the final frontier, is a hostile and unforgiving place for any form of life as we know it. The unique environment of space allows for a close simulation of Mars surface conditions that cannot be simulated as accurately on the Earth. For this experiment, we tested the resistance of Deinococcus radiodurans to survive exposure to simulated Mars-like conditions in low-Earth orbit for a prolonged period of time as part of the Biology and Mars experiment (BIOMEX) project. Special focus was placed on the integrity of the carotenoid deinoxanthin, which may serve as a potential biomarker to search for remnants of life on other planets. Survival was investigated by evaluating colony forming units, damage inflicted to the 16S rRNA gene by quantitative PCR, and the integrity and detectability of deinoxanthin by Raman spectroscopy. Exposure to space conditions had a strong detrimental effect on the survival of the strains and the 16S rRNA integrity, yet results show that deinoxanthin survives exposure to conditions as they prevail on Mars. Solar radiation is not only strongly detrimental to the survival and 16S rRNA integrity but also to the Raman signal of deinoxanthin. Samples not exposed to solar radiation showed only minuscule signs of deterioration. To test whether deinoxanthin is able to withstand the tested parameters without the protection of the cell, it was extracted from cell homogenate and exposed to high/low temperatures, vacuum, germicidal UV-C radiation, and simulated solar radiation. Results obtained by Raman investigations showed a strong resistance of deinoxanthin against outer space and Mars conditions, with the only exception of the exposure to simulated solar radiation. Therefore, deinoxanthin proved to be a suitable easily detectable biomarker for the search of Earth-like organic pigment-containing life on other planets. PMID:28966605
Leuko, Stefan; Bohmeier, Maria; Hanke, Franziska; Böettger, Ute; Rabbow, Elke; Parpart, Andre; Rettberg, Petra; de Vera, Jean-Pierre P
2017-01-01
Outer space, the final frontier, is a hostile and unforgiving place for any form of life as we know it. The unique environment of space allows for a close simulation of Mars surface conditions that cannot be simulated as accurately on the Earth. For this experiment, we tested the resistance of Deinococcus radiodurans to survive exposure to simulated Mars-like conditions in low-Earth orbit for a prolonged period of time as part of the Biology and Mars experiment (BIOMEX) project. Special focus was placed on the integrity of the carotenoid deinoxanthin, which may serve as a potential biomarker to search for remnants of life on other planets. Survival was investigated by evaluating colony forming units, damage inflicted to the 16S rRNA gene by quantitative PCR, and the integrity and detectability of deinoxanthin by Raman spectroscopy. Exposure to space conditions had a strong detrimental effect on the survival of the strains and the 16S rRNA integrity, yet results show that deinoxanthin survives exposure to conditions as they prevail on Mars. Solar radiation is not only strongly detrimental to the survival and 16S rRNA integrity but also to the Raman signal of deinoxanthin. Samples not exposed to solar radiation showed only minuscule signs of deterioration. To test whether deinoxanthin is able to withstand the tested parameters without the protection of the cell, it was extracted from cell homogenate and exposed to high/low temperatures, vacuum, germicidal UV-C radiation, and simulated solar radiation. Results obtained by Raman investigations showed a strong resistance of deinoxanthin against outer space and Mars conditions, with the only exception of the exposure to simulated solar radiation. Therefore, deinoxanthin proved to be a suitable easily detectable biomarker for the search of Earth-like organic pigment-containing life on other planets.
Cyber-Critical Infrastructure Protection Using Real-Time Payload-Based Anomaly Detection
NASA Astrophysics Data System (ADS)
Düssel, Patrick; Gehl, Christian; Laskov, Pavel; Bußer, Jens-Uwe; Störmann, Christof; Kästner, Jan
With an increasing demand of inter-connectivity and protocol standardization modern cyber-critical infrastructures are exposed to a multitude of serious threats that may give rise to severe damage for life and assets without the implementation of proper safeguards. Thus, we propose a method that is capable to reliably detect unknown, exploit-based attacks on cyber-critical infrastructures carried out over the network. We illustrate the effectiveness of the proposed method by conducting experiments on network traffic that can be found in modern industrial control systems. Moreover, we provide results of a throughput measuring which demonstrate the real-time capabilities of our system.
Testing the Turing Test — do Men Pass It?
NASA Astrophysics Data System (ADS)
Adam, Ruth; Hershberg, Uri; Schul, Yaacov; Solomon, Sorin
We are fascinated by the idea of giving life to the inanimate. The fields of Artificial Life and Artificial Intelligence (AI) attempt to use a scientific approach to pursue this desire. The first steps on this approach hark back to Turing and his suggestion of an imitation game as an alternative answer to the question "can machines think?".1 To test his hypothesis, Turing formulated the Turing test1 to detect human behavior in computers. But how do humans pass such a test? What would you say if you would learn that they do not pass it well? What would it mean for our understanding of human behavior? What would it mean for our design of tests of the success of artificial life? We report below an experiment in which men consistently failed the Turing test.
[Carcinogenic efficacy of the transuranium elements americium-241 and curium-244].
Rudnitskaia, E I
1984-01-01
Albino female rats were used in the experiments. After a single intraperitoneal administration of 241Am and 244Cm chloride is doses ranging from 0.37 to 185 kBq/kg (14 doses were used) it was established that the doses applied had different effect on the average life of animals. The largest doses shortened and the lowest increased the life span of experimental animals as compared to the controls. The carcinogenic effect of the studied radionuclides and the development of malignant tumors were detected at sufficiently low doses absorbed. Malignant tumors developed in the experimental and control animals were different not only in their incidence but also their localization and spectrum.
Microscale Determination of Vitamin C by Weight Titrimetry
NASA Astrophysics Data System (ADS)
East, Gaston A.; Nascimento, Erica C.
2002-01-01
A laboratory experiment involving the quantitative microscale determination of ascorbic acid in pharmaceutical tablets of vitamin C by weight-titrimetry using (diacetoxyiodo)benzene as titrant and differential electrolytic potentiometry to locate the end-point is presented. The experiment affords an opportunity for students to explore nonconventional techniques such as the use of a novel organic oxidimetric titrant, titration in a semiaqueous medium, gravimetric titration, and an electrometric method of end-point detection using polarized electrodes. Synthesis, purification, and purity checking of the titrant may also be included in the project. Some advantages of the method are very low reagent consumption, low-cost equipment, improved sensitivity, and high precision and accuracy. Furthermore, the experiment will help the student to relate chemical analysis to everyday life.
NASA Astrophysics Data System (ADS)
Shyu, Mei-Ling; Huang, Zifang; Luo, Hongli
In recent years, pervasive computing infrastructures have greatly improved the interaction between human and system. As we put more reliance on these computing infrastructures, we also face threats of network intrusion and/or any new forms of undesirable IT-based activities. Hence, network security has become an extremely important issue, which is closely connected with homeland security, business transactions, and people's daily life. Accurate and efficient intrusion detection technologies are required to safeguard the network systems and the critical information transmitted in the network systems. In this chapter, a novel network intrusion detection framework for mining and detecting sequential intrusion patterns is proposed. The proposed framework consists of a Collateral Representative Subspace Projection Modeling (C-RSPM) component for supervised classification, and an inter-transactional association rule mining method based on Layer Divided Modeling (LDM) for temporal pattern analysis. Experiments on the KDD99 data set and the traffic data set generated by a private LAN testbed show promising results with high detection rates, low processing time, and low false alarm rates in mining and detecting sequential intrusion detections.
Infrared small target detection technology based on OpenCV
NASA Astrophysics Data System (ADS)
Liu, Lei; Huang, Zhijian
2013-05-01
Accurate and fast detection of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. In this paper, some basic principles and the implementing flow charts of a series of algorithms for target detection are described. These algorithms are traditional two-frame difference method, improved three-frame difference method, background estimate and frame difference fusion method, and building background with neighborhood mean method. On the foundation of above works, an infrared target detection software platform which is developed by OpenCV and MFC is introduced. Three kinds of tracking algorithms are integrated in this software. In order to explain the software clearly, the framework and the function are described in this paper. At last, the experiments are performed for some real-life IR images. The whole algorithm implementing processes and results are analyzed, and those algorithms for detection targets are evaluated from the two aspects of subjective and objective. The results prove that the proposed method has satisfying detection effectiveness and robustness. Meanwhile, it has high detection efficiency and can be used for real-time detection.
Infrared small target detection technology based on OpenCV
NASA Astrophysics Data System (ADS)
Liu, Lei; Huang, Zhijian
2013-09-01
Accurate and fast detection of infrared (IR) dim target has very important meaning for infrared precise guidance, early warning, video surveillance, etc. In this paper, some basic principles and the implementing flow charts of a series of algorithms for target detection are described. These algorithms are traditional two-frame difference method, improved three-frame difference method, background estimate and frame difference fusion method, and building background with neighborhood mean method. On the foundation of above works, an infrared target detection software platform which is developed by OpenCV and MFC is introduced. Three kinds of tracking algorithms are integrated in this software. In order to explain the software clearly, the framework and the function are described in this paper. At last, the experiments are performed for some real-life IR images. The whole algorithm implementing processes and results are analyzed, and those algorithms for detection targets are evaluated from the two aspects of subjective and objective. The results prove that the proposed method has satisfying detection effectiveness and robustness. Meanwhile, it has high detection efficiency and can be used for real-time detection.
Consensus-based methodology for detection communities in multilayered networks
NASA Astrophysics Data System (ADS)
Karimi-Majd, Amir-Mohsen; Fathian, Mohammad; Makrehchi, Masoud
2018-03-01
Finding groups of network users who are densely related with each other has emerged as an interesting problem in the area of social network analysis. These groups or so-called communities would be hidden behind the behavior of users. Most studies assume that such behavior could be understood by focusing on user interfaces, their behavioral attributes or a combination of these network layers (i.e., interfaces with their attributes). They also assume that all network layers refer to the same behavior. However, in real-life networks, users' behavior in one layer may differ from their behavior in another one. In order to cope with these issues, this article proposes a consensus-based community detection approach (CBC). CBC finds communities among nodes at each layer, in parallel. Then, the results of layers should be aggregated using a consensus clustering method. This means that different behavior could be detected and used in the analysis. As for other significant advantages, the methodology would be able to handle missing values. Three experiments on real-life and computer-generated datasets have been conducted in order to evaluate the performance of CBC. The results indicate superiority and stability of CBC in comparison to other approaches.
Root Cause Analysis of Sexual Assault: Shifting from Early Detection to a Vaccine
2015-02-17
Women Bystander Behavior Basic Development /Personal Identity Sexuality Pornography Dating STDs/Communicable Diseases He Said/She Said - Mars vs Venus...trust over time and sharing of current life experiences allows for “ developmental coaching” (CCLD, “ Developing Leaders,” 21) in a safe environment...skill development . Just as root sources for cancer are mitigated by not smoking, minimal sun exposure, adopting healthy eating habits and alcohol use
Habitable worlds with no signs of life.
Cockell, Charles S
2014-04-28
'Most habitable worlds in the cosmos will have no remotely detectable signs of life' is proposed as a biological hypothesis to be tested in the study of exoplanets. Habitable planets could be discovered elsewhere in the Universe, yet there are many hypothetical scenarios whereby the search for life on them could yield negative results. Scenarios for habitable worlds with no remotely detectable signatures of life include: planets that are habitable, but have no biosphere (Uninhabited Habitable Worlds); planets with life, but lacking any detectable surface signatures of that life (laboratory examples are provided); and planets with life, where the concentrations of atmospheric gases produced or removed by biota are impossible to disentangle from abiotic processes because of the lack of detailed knowledge of planetary conditions (the 'problem of exoplanet thermodynamic uncertainty'). A rejection of the hypothesis would require that the origin of life usually occurs on habitable planets, that spectrally detectable pigments and/or metabolisms that produce unequivocal biosignature gases (e.g. oxygenic photosynthesis) usually evolve and that the organisms that harbour them usually achieve a sufficient biomass to produce biosignatures detectable to alien astronomers.
[Detection of organic compounds on Mars].
Kobayashi, K
1997-03-01
McKay et al. detected polycyclic aromatic hydrocarbons (PAHs) in Martian meteorite ALH 84001 by two-step laser mass spectrometry. From the presence of PAHs, together with other results, they concluded that there were past life of Mars. On the other hands, no organisms nor organic compounds were detected in Martian regolith in Viking experiments in 1976. In order to obtain solid evidence for organisms or bioorganic compounds compounds on Mars, further analyses of Martian samples are required. There may be four classes of organic compounds on Mars, which are (i) organic compounds abiotically formed from primitive Mars atmosphere, (ii) Organic compounds delivered out of Mars, (iii) Organic compounds biotically formed by Mars organisms, and (iv) Organic compounds abiotically formed from the present Mars atmosphere. Possible organic compounds on Mars and analytical methods for them are discussed.
Alpern, Adrianne N; Gardner, Melissa; Kogan, Barry; Sandberg, David E; Quittner, Alexandra L
2017-06-01
Research in disorders of sex development (DSD) is hindered by a lack of standardized measures sensitive to the experiences of affected children and families. We developed and evaluated parent proxy (children 2-6 years) and parent self-report (children ≤6 years) health-related quality of life (HRQoL) instruments for DSD. Items were derived from focus groups and open-ended interviews. Clarity and comprehensiveness were assessed with cognitive interviews. Psychometric properties were examined in a field survey of 94 families. Measures demonstrated adequate to good psychometrics, including internal consistency, test-retest reliability, convergent validity, and ability to detect known-group differences. Parents reported greatest stress on Early Experiences , Surgery , and Future Concerns scales. These instruments identify patients' and families' needs, monitor health and quality of life status, and can evaluate clinical interventions. Findings highlight the need for improved psychosocial support during the diagnostic period, better parent-provider communication, and shared decision-making. HRQoL measures are needed for older youth. © The Author 2016. Published by Oxford University Press on behalf of the Society of Pediatric Psychology. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com
NASA Astrophysics Data System (ADS)
Direito, Susana O. L.; Ehrenfreund, Pascale; Marees, Andries; Staats, Martijn; Foing, Bernard; Röling, Wilfred F. M.
2011-07-01
Humankind's innate curiosity makes us wonder whether life is or was present on other planetary bodies such as Mars. The EuroGeoMars 2009 campaign was organized at the Mars Desert Research Station (MDRS) to perform multidisciplinary astrobiology research. MDRS in southeast Utah is situated in a cold arid desert with mineralogy and erosion processes comparable to those on Mars. Insight into the microbial community composition of this terrestrial Mars analogue provides essential information for the search for life on Mars: including sampling and life detection methodology optimization and what kind of organisms to expect. Soil samples were collected from different locations. Culture-independent molecular analyses directed at ribosomal RNA genes revealed the presence of all three domains of life (Archaea, Bacteria and Eukarya), but these were not detected in all samples. Spiking experiments revealed that this appears to relate to low DNA recovery, due to adsorption or degradation. Bacteria were most frequently detected and showed high alpha- and beta-diversity. Members of the Actinobacteria, Proteobacteria, Bacteroidetes and Gemmatimonadetes phyla were found in the majority of samples. Archaea alpha- and beta-diversity was very low. For Eukarya, a diverse range of organisms was identified, such as fungi, green algae and several phyla of Protozoa. Phylogenetic analysis revealed an extraordinary variety of putative extremophiles, mainly Bacteria but also Archaea and Eukarya. These comprised radioresistant, endolithic, chasmolithic, xerophilic, hypolithic, thermophilic, thermoacidophilic, psychrophilic, halophilic, haloalkaliphilic and alkaliphilic micro-organisms. Overall, our data revealed large difference in occurrence and diversity over short distances, indicating the need for high-sampling frequency at similar sites. DNA extraction methods need to be optimized to improve extraction efficiencies.
45 CFR 158.231 - Life-years used to determine credible experience.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 45 Public Welfare 1 2013-10-01 2013-10-01 false Life-years used to determine credible experience... and Providing the Rebate § 158.231 Life-years used to determine credible experience. (a) The life-years used to determine the credibility of an issuer's experience are the life-years for the MLR...
45 CFR 158.231 - Life-years used to determine credible experience.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 45 Public Welfare 1 2014-10-01 2014-10-01 false Life-years used to determine credible experience... and Providing the Rebate § 158.231 Life-years used to determine credible experience. (a) The life-years used to determine the credibility of an issuer's experience are the life-years for the MLR...
Ferrate (IV) as a Possible Oxidant on the Martian Surface
NASA Astrophysics Data System (ADS)
Tsapin, Alexandre; Goldfeld, M. G.; McDonald, G. D.; Nealson, K. H.; Mohnke, J.; Moskovitz, B.; Solheid, P.; Kemner, K. H.; Orlandini, K.
Viking experiments showed that Martian soil has a very strong oxidant, which could be responsible for the results of experiments performed on Viking landers. These experiments were designed specifically to detect life on Mars. The nature of that oxidant was not determined during Viking mission. Later several groups tried to reconstruct Viking experiments and find out the nature of Martian oxidant. None of these attempts were completely successful. The general perception was that there are several chemically different oxidants on Martian surface. In this study we suggested that potassium ferrate K_2FeO_4 can be Martian oxidant responsible at least partially for the results of experiments on Viking landers. We characterized liquid and powder preparation of Fe (VI) with EPR, optical spectroscopy, Mossbauer spectroscopy, and by Fe-XANES. All properties of our preparations of (FeVI) are consistent with the proposal role of that compound as a strong oxidant on Martian surface.
Massetti, Greta M; Ragan, Kathleen R; Thomas, Cheryll C; Ryerson, A Blythe
2015-10-20
Advances in cancer prevention, detection, and treatment have led to reductions in morbidity and premature mortality and improvements in quality of life. However, not all Americans have benefitted equally from these advances, and certain populations experience continued disparities in cancer care. Although research and public health efforts have highlighted the experiences of some groups, other populations have been relatively understudied, such as lesbian, gay, bisexual, and transgender (LGBT) individuals. Public health efforts in surveillance, research, programs, and partnerships can provide opportunities to advance health equity for LGBT at the population level and lead to better health outcomes for LGBT individuals with cancer.
NASA Astrophysics Data System (ADS)
Meroz, Yasmine
2015-06-01
In the 1980s the world witnessed the advent of single-molecule experiments. The first atomic resolution characterization of a surface was reported by scanning tunneling microscope (STM) in 1982 [1], followed by atomic force microscope (AFM) in 1986 [2]. The first optical detection and spectroscopy of a single molecule in a solid took place in 1989 [3,4], in a time where essentially all chemical experiments were made on bulk, i.e. averaging over millions of copies of the same molecule.
Possibilities for the detection of microbial life on extrasolar planets.
Knacke, Roger F
2003-01-01
We consider possibilities for the remote detection of microbial life on extrasolar planets. The Darwin/Terrestrial Planet Finder (TPF) telescope concepts for observations of terrestrial planets focus on indirect searches for life through the detection of atmospheric gases related to life processes. Direct detection of extraterrestrial life may also be possible through well-designed searches for microbial life forms. Satellites in Earth orbit routinely monitor colonies of terrestrial algae in oceans and lakes by analysis of reflected ocean light in the visible region of the spectrum. These remote sensing techniques suggest strategies for extrasolar searches for signatures of chlorophylls and related photosynthetic compounds associated with life. However, identification of such life-related compounds on extrasolar planets would require observations through strong, interfering absorptions and scattering radiances from the remote atmospheres and landmasses. Techniques for removal of interfering radiances have been extensively developed for remote sensing from Earth orbit. Comparable techniques would have to be developed for extrasolar planet observations also, but doing so would be challenging for a remote planet. Darwin/TPF coronagraph concepts operating in the visible seem to be best suited for searches for extrasolar microbial life forms with instruments that can be projected for the 2010-2020 decades, although resolution and signal-to-noise ratio constraints severely limit detection possibilities on terrestrial-type planets. The generation of telescopes with large apertures and extremely high spatial resolutions that will follow Darwin/TPF could offer striking possibilities for the direct detection of extrasolar microbial life.
NMR spectroscopy of single sub-nL ova with inductive ultra-compact single-chip probes
Grisi, Marco; Vincent, Franck; Volpe, Beatrice; Guidetti, Roberto; Harris, Nicola; Beck, Armin; Boero, Giovanni
2017-01-01
Nuclear magnetic resonance (NMR) spectroscopy enables non-invasive chemical studies of intact living matter. However, the use of NMR at the volume scale typical of microorganisms is hindered by sensitivity limitations, and experiments on single intact organisms have so far been limited to entities having volumes larger than 5 nL. Here we show NMR spectroscopy experiments conducted on single intact ova of 0.1 and 0.5 nL (i.e. 10 to 50 times smaller than previously achieved), thereby reaching the relevant volume scale where life development begins for a broad variety of organisms, humans included. Performing experiments with inductive ultra-compact (1 mm2) single-chip NMR probes, consisting of a low noise transceiver and a multilayer 150 μm planar microcoil, we demonstrate that the achieved limit of detection (about 5 pmol of 1H nuclei) is sufficient to detect endogenous compounds. Our findings suggest that single-chip probes are promising candidates to enable NMR-based study and selection of microscopic entities at biologically relevant volume scales. PMID:28317887
Atmospheric scavenging exhaust
NASA Technical Reports Server (NTRS)
Fenton, D. L.; Purcell, R. Y.
1977-01-01
Solid propellant rocket exhaust was directly utilized to ascertain raindrop scavenging rates for hydrogen chloride. The airborne HCl concentration varied from 0.2 to 10.0 ppm and the raindrop sizes tested included 0.55 mm, 1.1 mm, and 3.0 mm. Two chambers were used to conduct the experiments. A large, rigid walled, spherical chamber stored the exhaust constituents while the smaller chamber housing all the experiments was charged as required with rocket exhaust HCl. Surface uptake experiments demonstrated an HCl concentration dependence for distilled water. Sea water and brackish water HCl uptake was below the detection limit of the chlorine-ion analysis technique employed. Plant life HCl uptake experiments were limited to corn and soybeans. Plant age effectively correlated the HCl uptake data. Metallic corrosion was not significant for single 20 minute exposures to the exhaust HCl under varying relative humidity.
Atmospheric scavenging of solid rocket exhaust effluents
NASA Technical Reports Server (NTRS)
Fenton, D. L.; Purcell, R. Y.
1978-01-01
Solid propellant rocket exhaust was directly utilized to ascertain raindrop scavenging rates for hydrogen chloride. Two chambers were used to conduct the experiments; a large, rigid walled, spherical chamber stored the exhaust constituents, while the smaller chamber housing all the experiments was charged as required with rocket exhaust HCl. Surface uptake experiments demonstrated an HCl concentration dependence for distilled water. Sea water and brackish water HCl uptake was below the detection limit of the chlorine-ion analysis technique used. Plant life HCl uptake experiments were limited to corn and soybeans. Plant age effectively correlated the HCl uptake data. Metallic corrosion was not significant for single 20 minute exposures to the exhaust HCl under varying relative humidity. Characterization of the aluminum oxide particles substantiated the similarity between the constituents of the small scale rocket and the full size vehicles.
What are the best ways to look for extinct or extant life on mars? Thinking outside the box
NASA Astrophysics Data System (ADS)
Bada, J. L.; Grunthaner, F.; Mathies, R.
2003-12-01
Although the Viking missions a quarter century ago performed a series of life detection experiments, the question of whether life ever existed or even still exists on Mars remains unanswered. The finding that the Martian surface is highly oxidizing seemed to preclude the presence of a robust surface biology, but the subsurface may be more compatible with respect to the survival of both viable organisms (1) and organic compounds. Moreover, it is now also known that the Viking GCMS would not have detected refractory organic compounds (2) or amino acids associated with over a million bacterial cells in a gram of soil (3). The entire Mars community now faces a major challenge as to what we should do next in our search for evidence of life on Mars. The option that is presently favored is to fly "safe" missions focused on characterizing the mineral and elemental makeup of the surface with little emphasis on state-of-the-art analyses for important biomarkers. A second, or perhaps parallel, bolder approach would be to fly payloads made up of highly sensitive instruments designed to search for a wide variety of key organic compounds. Instrumentation available to detect trace levels of key biological compounds have improved dramatically since the Viking missions and many of these methods can be miniaturized so they can be accommodated into a spacecraft. The critical issue is what suite of instruments would provide the most definitive results in answering the life on Mars question. To rigorously address this question, we propose that various organic detection systems be extensively tested in situ using a common and well controlled set of samples in an environment that is known to have low levels of both microbes and organic compounds. One locality that would be a strong candidate is the Yungay Station site in the Atacama desert of Chile, one of the driest and harshest places on Earth. Only those instruments that are able to detect at high sensitivity organic biomarkers in a natural field situation such as this should be considered for components for a future Mars mission payload package. If an instrument can not detect the presence of life's organic signature here on Earth, there is no justification for flying this instrument in a payload to Mars! NIH and DOE embarked upon a similar critical competition to development the best methodology to sequence the human genome and this process was dramically successful. NASA's search for possible signs of life on Mars deserves at the same level of critical and competitive decision-making where scientific capability rather than other factors determine what is included in payloads. 1. B. P. Weiss et al, Proc. Natl Acad. Sci USA 97, 1395 (2000). 2. S. A. Benner et al, Proc. Natl Acad. Sci USA 97, 2425 (2000). 3. D. P. Glavin et al, Earth Planet. Sci. Lettrs. 185, 1 (2001).
[Space experiments on the development of biological systems for the human life].
Sychev, V N
2013-01-01
Over the past 22 years, the Institute of Biomedical Problems has stubbornly continued the investigations with higher plants aimed at the development of cultivation technologies suitable for the conditions of space flight. Analysis of the results of 24 plant experiments performed aboard orbital complex MIR and the ISS Russian segment evidenced the ability of higher plants to grow, develop and reproduce inside spacecraft living compartments. Space crops were normal as compared with the laboratory controls. Microbial contamination of the plants was within the normal limits; no pathogen has been detected on plant surfaces. Plants did not change genetically, at least in four space generations. It should be noted that the presence of greenhouse on board the ISS also has a marked positive effect on wellbeing of people living in the close environment and isolation from Earth's biosphere. In the context of the above, the higher plants might become a secure and beneficial part of the life support system for crews on space exploration missions.
Using a high spatial resolution tactile sensor for intention detection.
Castellini, Claudio; Koiva, Risto
2013-06-01
Intention detection is the interpretation of biological signals with the aim of automatically, reliably and naturally understanding what a human subject desires to do. Although intention detection is not restricted to disabled people, such methods can be crucial in improving a patient's life, e.g., aiding control of a robotic wheelchair or of a self-powered prosthesis. Traditionally, intention detection is done using, e.g., gaze tracking, surface electromyography and electroencephalography. In this paper we present exciting initial results of an experiment aimed at intention detection using a high-spatial-resolution, high-dynamic-range tactile sensor. The tactile image of the ventral side of the forearm of 9 able-bodied participants was recorded during a variable-force task stimulated at the fingertip. Both the forces at the fingertip and at the forearm were synchronously recorded. We show that a standard dimensionality reduction technique (Principal Component Analysis) plus a Support Vector Machine attain almost perfect detection accuracy of the direction and the intensity of the intended force. This paves the way for high spatial resolution tactile sensors to be used as a means for intention detection.
Spectrum analysis of radar life signal in the three kinds of theoretical models
NASA Astrophysics Data System (ADS)
Yang, X. F.; Ma, J. F.; Wang, D.
2017-02-01
In the single frequency continuous wave radar life detection system, based on the Doppler effect, the theory model of radar life signal is expressed by the real function, and there is a phenomenon that can't be confirmed by the experiment. When the phase generated by the distance between the measured object and the radar measuring head is л of integer times, the main frequency spectrum of life signal (respiration and heartbeat) is not existed in radar life signal. If this phase is л/2 of odd times, the main frequency spectrum of breath and heartbeat frequency is the strongest. In this paper, we use the Doppler effect as the basic theory, using three different mathematical expressions——real function, complex exponential function and Bessel's function expansion form. They are used to establish the theoretical model of radar life signal. Simulation analysis revealed that the Bessel expansion form theoretical model solve the problem of real function form. Compared with the theoretical model of the complex exponential function, the derived spectral line is greatly reduced in the theoretical model of Bessel expansion form, which is more consistent with the actual situation.
Habitable worlds with no signs of life
Cockell, Charles S.
2014-01-01
‘Most habitable worlds in the cosmos will have no remotely detectable signs of life’ is proposed as a biological hypothesis to be tested in the study of exoplanets. Habitable planets could be discovered elsewhere in the Universe, yet there are many hypothetical scenarios whereby the search for life on them could yield negative results. Scenarios for habitable worlds with no remotely detectable signatures of life include: planets that are habitable, but have no biosphere (Uninhabited Habitable Worlds); planets with life, but lacking any detectable surface signatures of that life (laboratory examples are provided); and planets with life, where the concentrations of atmospheric gases produced or removed by biota are impossible to disentangle from abiotic processes because of the lack of detailed knowledge of planetary conditions (the ‘problem of exoplanet thermodynamic uncertainty’). A rejection of the hypothesis would require that the origin of life usually occurs on habitable planets, that spectrally detectable pigments and/or metabolisms that produce unequivocal biosignature gases (e.g. oxygenic photosynthesis) usually evolve and that the organisms that harbour them usually achieve a sufficient biomass to produce biosignatures detectable to alien astronomers. PMID:24664917
A Field-Based Cleaning Protocol for Sampling Devices Used in Life-Detection Studies
NASA Astrophysics Data System (ADS)
Eigenbrode, Jennifer; Benning, Liane G.; Maule, Jake; Wainwright, Norm; Steele, Andrew; Amundsen, Hans E. F.
2009-06-01
Analytical approaches to extant and extinct life detection involve molecular detection often at trace levels. Thus, removal of biological materials and other organic molecules from the surfaces of devices used for sampling is essential for ascertaining meaningful results. Organic decontamination to levels consistent with null values on life-detection instruments is particularly challenging at remote field locations where Mars analog field investigations are carried out. Here, we present a seven-step, multi-reagent decontamination method that can be applied to sampling devices while in the field. In situ lipopolysaccharide detection via low-level endotoxin assays and molecular detection via gas chromatography-mass spectrometry were used to test the effectiveness of the decontamination protocol for sampling of glacial ice with a coring device and for sampling of sediments with a rover scoop during deployment at Arctic Mars-analog sites in Svalbard, Norway. Our results indicate that the protocols and detection technique sufficiently remove and detect low levels of molecular constituents necessary for life-detection tests.
A field-based cleaning protocol for sampling devices used in life-detection studies.
Eigenbrode, Jennifer; Benning, Liane G; Maule, Jake; Wainwright, Norm; Steele, Andrew; Amundsen, Hans E F
2009-06-01
Analytical approaches to extant and extinct life detection involve molecular detection often at trace levels. Thus, removal of biological materials and other organic molecules from the surfaces of devices used for sampling is essential for ascertaining meaningful results. Organic decontamination to levels consistent with null values on life-detection instruments is particularly challenging at remote field locations where Mars analog field investigations are carried out. Here, we present a seven-step, multi-reagent decontamination method that can be applied to sampling devices while in the field. In situ lipopolysaccharide detection via low-level endotoxin assays and molecular detection via gas chromatography-mass spectrometry were used to test the effectiveness of the decontamination protocol for sampling of glacial ice with a coring device and for sampling of sediments with a rover scoop during deployment at Arctic Mars-analog sites in Svalbard, Norway. Our results indicate that the protocols and detection technique sufficiently remove and detect low levels of molecular constituents necessary for life-detection tests.
Vedder, Oscar; Kürten, Nathalie; Bouwhuis, Sandra
Embryonic development time is thought to impact life histories through trade-offs against life-history traits later in life, yet the inference is based on interspecific comparative analyses only. It is largely unclear whether intraspecific variation in embryonic development time that is not caused by environmental differences occurs, which would be required to detect life-history trade-offs. Here we performed a classical common-garden experiment by incubating fresh eggs of free-living common terns (Sterna hirundo) in a controlled incubation environment at two different temperatures. Hatching success was high but was slightly lower at the lower temperature. While correcting for effects of year, incubation temperature, and laying order, we found significant variation in the incubation time embryos required until hatching and in their heart rate. Embryonic heart rate was significantly positively correlated within clutches, and a similar tendency was found for incubation time, suggesting that intrinsic differences in embryonic development rate between offspring of different parents exist. Incubation time and embryonic heart rate were strongly correlated: embryos with faster heart rates required shorter incubation time. However, after correction for heart rate, embryos still required more time for development at the lower incubation temperature. This suggests that processes other than development require a greater share of resources in a suboptimal environment and that relative resource allocation to development is, therefore, environment dependent. We conclude that there is opportunity to detect intraspecific life-history trade-offs with embryonic development time and that the resolution of trade-offs may differ between embryonic environments.
Perspectives on the Future Search for Life on Mars and Beyond
NASA Technical Reports Server (NTRS)
Nealson, K. H.
1998-01-01
One can view the search for life on Mars in two ways: first, as the initial step in the search for life elsewhere, and second, as the one place where in situ methods for life detection can be tested and proved via sample return. After Mars, most of the life detection will he done via in situ studies with data return. Mars offers us the opportunity to fine tune our methods - perhaps for a long time to come. Our group is involved in the development of methods for life detection that are independent of specific signals used for detection of life on Earth. These approaches include general indicators of metabolic activity and organismal structure and composition. Using such approaches, we hope to detect the signals of life (biosignatures) that are independent of preconceived notions and yet are convincing and unambiguous. The approaches we are focusing on include stable isotopic analyses of metals, mineral formation and disolution, and elemental analysis. These methods allow us to examine samples at a variety of scales, looking for nonequilibrium distribution of elements that serve as biosignatures. For futures studies of Mars and beyond, they, or some variation of them, should allow inference or proof of life in non-Earth locations.
Podolich, O; Zaets, I; Kukharenko, O; Orlovska, I; Reva, O; Khirunenko, L; Sosnin, M; Haidak, A; Shpylova, S; Rohutskyy, I; Kharina, A; Skoryk, М; Kremenskoy, M; Klymchuk, D; Demets, R; de Vera, J-P; Kozyrovska, N
2017-06-01
Biofilm-forming microbial communities are known as the most robust assemblages that can survive in harsh environments. Biofilm-associated microorganisms display greatly increased resistance to physical and chemical adverse conditions, and they are expected to be the first form of life on Earth or anywhere else. Biological molecules synthesized by biofilm -protected microbiomes may serve as markers of the nucleoprotein life. We offer a new experimental model, a kombucha multimicrobial culture (KMC), to assess a structural integrity of a widespread microbial polymer - cellulose - as a biosignature of bacteria-producers for the multipurpose international project "BIOlogical and Mars Experiment (BIOMEX)", which aims to study the vitality of pro- and eukaryotic organisms and the stability of organic biomolecules in contact with minerals to analyze the detectability of life markers in the context of a planetary background. In this study, we aimed to substantiate the detectability of mineralized cellulose with spectroscopy and to study the KMC macrocolony phenotype stability under adverse conditions (UV, excess of inorganics etc.). Cellulose matrix of the KMC macrocolony has been mineralized in the mineral-water interface under assistance of KMC-members. Effect of bioleached ions on the cellulose matrix has been visible, and the FT-IR spectrum proved changes in cellulose structure. However, the specific cellulose band vibration, confirming the presence of β(1,4)-linkages between monomers, has not been quenched by secondary minerals formed on the surface of pellicle. The cellulose-based KMC macrocolony phenotype was in a dependence on extracellular matrix components (ionome, viriome, extracellular membrane vesicles), which provided its integrity and rigidness in a certain extent under impact of stressful factors.
NASA Astrophysics Data System (ADS)
Podolich, O.; Zaets, I.; Kukharenko, O.; Orlovska, I.; Reva, O.; Khirunenko, L.; Sosnin, M.; Haidak, A.; Shpylova, S.; Rohutskyy, I.; Kharina, A.; Skoryk, M.; Kremenskoy, M.; Klymchuk, D.; Demets, R.; de Vera, J.-P.; Kozyrovska, N.
2017-06-01
Biofilm-forming microbial communities are known as the most robust assemblages that can survive in harsh environments. Biofilm-associated microorganisms display greatly increased resistance to physical and chemical adverse conditions, and they are expected to be the first form of life on Earth or anywhere else. Biological molecules synthesized by biofilm -protected microbiomes may serve as markers of the nucleoprotein life. We offer a new experimental model, a kombucha multimicrobial culture (KMC), to assess a structural integrity of a widespread microbial polymer - cellulose - as a biosignature of bacteria-producers for the multipurpose international project "BIOlogical and Mars Experiment (BIOMEX)", which aims to study the vitality of pro- and eukaryotic organisms and the stability of organic biomolecules in contact with minerals to analyze the detectability of life markers in the context of a planetary background. In this study, we aimed to substantiate the detectability of mineralized cellulose with spectroscopy and to study the KMC macrocolony phenotype stability under adverse conditions (UV, excess of inorganics etc.). Cellulose matrix of the KMC macrocolony has been mineralized in the mineral-water interface under assistance of KMC-members. Effect of bioleached ions on the cellulose matrix has been visible, and the FT-IR spectrum proved changes in cellulose structure. However, the specific cellulose band vibration, confirming the presence of β(1,4)-linkages between monomers, has not been quenched by secondary minerals formed on the surface of pellicle. The cellulose-based KMC macrocolony phenotype was in a dependence on extracellular matrix components (ionome, viriome, extracellular membrane vesicles), which provided its integrity and rigidness in a certain extent under impact of stressful factors.
The Detection of Extraterrestrial Life: Are We Ready?
NASA Astrophysics Data System (ADS)
Capova, Klara Anna
This chapter offers a sociocultural perspective on the scientific search for life beyond Earth. It sheds light on the ways in which alien life is imagined and theorized in order to assess the possible societal response to the detection of other life. This chapter is based on the findings of research conducted over two years in the UK, which conceptualizes the extraterrestrial life hypothesis as a significant part of the general worldview, constantly shaped by the work and discoveries of science. Based on these data, the chapter offers insights into the current Western concepts of other life as understood, perceived, and interpreted by the scientific community and popular culture. The post-detection scenarios currently discussed deal mostly with a profound cultural shock following discovery of a superior extraterrestrial civilization. In contrast, the most recent scientific quest for other life now operates with a distinctly different concept of extraterrestrial life that ushers in other possible reactions to a detection or a contact. To establish current concepts of other life then seems to be crucial for predicting the societal response to a first contact. The chapter presents an overview of multiple conceptions of other life in science and science fiction to outline the potential variety of responses. The aim of this chapter is to suggest that the societal readiness and overall acceptance of the other life hypothesis needs to be taken into account and that the actual response to the discovery of other life will be determined by the actual form or type of life detected. This chapter will present examples from science fiction and other ethnographic material collected during fieldwork to demonstrate how popular culture has adapted the other life idea and how the presupposed other life is perceived.
Race Differences in the Association of Spiritual Experiences and Life Satisfaction in Older Age
Skarupski, Kimberly A.; Fitchett, George; Evans, Denis A.; de Leon, Carlos F. Mendes
2013-01-01
Objectives The primary objective of this study was to examine an African American ‘faith advantage’ in life satisfaction. Specifically, we sought to test the hypothesis that the positive relationship between spiritual experiences and life satisfaction is stronger among older African Americans than among older Whites. Method The data came from 6,864 community-dwelling persons aged 65+ (66% African American) who participated in the Chicago Health and Aging Project. Life satisfaction was measured using a five-item composite and we used a five-item version of the Daily Spiritual Experiences scale. Results In a regression model adjusting for age, sex, marital status, education, income, and worship attendance, we found that African American race was associated with lower life satisfaction. We also found a positive association between spiritual experiences and life satisfaction. In an additional model, a significant race × spiritual experiences interaction term indicates that spiritual experiences are more positively associated with life satisfaction among African Americans. Conclusion The data suggest that at higher levels of spiritual experiences, racial differences in life satisfaction are virtually non-existent. However, at lower levels of spiritual experiences, older African Americans show modestly lower levels of life satisfaction than do older Whites. This pattern suggests that spiritual experiences are a positive resource - distinct from worship attendance- that enable older African Americans to overcome decrements in life satisfaction and in fact, that lower spiritual experiences may be especially harmful for older African American’s life satisfaction. PMID:23627686
Development of Solid-State Nanopore Technology for Life Detection
NASA Technical Reports Server (NTRS)
Bywaters, K. B.; Schmidt, H.; Vercoutere, W.; Deamer, D.; Hawkins, A. R.; Quinn, R. C.; Burton, A. S.; Mckay, C. P.
2017-01-01
Biomarkers for life on Earth are an important starting point to guide the search for life elsewhere. However, the search for life beyond Earth should incorporate technologies capable of recognizing an array of potential biomarkers beyond what we see on Earth, in order to minimize the risk of false negatives from life detection missions. With this in mind, charged linear polymers may be a universal signature for life, due to their ability to store information while also inherently reducing the tendency of complex tertiary structure formation that significantly inhibit replication. Thus, these molecules are attractive targets for biosignature detection as potential "self-sustaining chemical signatures." Examples of charged linear polymers, or polyelectrolytes, include deoxyribonucleic acid (DNA) and ribonucleic acid (RNA) as well as synthetic polyelectrolytes that could potentially support life, including threose nucleic acid (TNA) and other xenonucleic acids (XNAs). Nanopore analysis is a novel technology that has been developed for singlemolecule sequencing with exquisite single nucleotide resolution which is also well-suited for analysis of polyelectrolyte molecules. Nanopore analysis has the ability to detect repeating sequences of electrical charges in organic linear polymers, and it is not molecule- specific (i.e. it is not restricted to only DNA or RNA). In this sense, it is a better life detection technique than approaches that are based on specific molecules, such as the polymerase chain reaction (PCR), which requires that the molecule being detected be composed of DNA.
ERIC Educational Resources Information Center
Weststrate, Nic M.; Glück, Judith
2017-01-01
Laypersons and experts believe that wisdom is cultivated through a diverse range of positive and negative life experiences. Yet, not all individuals with life experience are wise. We propose that one possible determinant of growth in wisdom from life experience is self-reflection. In a life span sample of adults (N = 94) ranging from 26 to 92…
Tauscher, Courtney; Schuerger, Andrew C; Nicholson, Wayne L
2006-08-01
Bacterial spores have been considered as microbial life that could survive interplanetary transport by natural impact processes or human spaceflight activity. Deposition of terrestrial microbes or their biosignature molecules onto the surface of Mars could negatively impact life detection experiments and planetary protection measures. Simulated Mars solar radiation, particularly the ultraviolet component, has been shown to reduce spore viability, but its effect on spore germination and resulting production of biosignature molecules has not been explored. We examined the survival and germinability of Bacillus subtilis spores exposed to simulated martian conditions that include solar radiation. Spores of B. subtilis that contain luciferase resulting from expression of an sspB-luxAB gene fusion were deposited on aluminum coupons to simulate deposition on spacecraft surfaces and exposed to simulated Mars atmosphere and solar radiation. The equivalent of 42 min of simulated Mars solar radiation exposure reduced spore viability by nearly 3 logs, while germination-induced bioluminescence, a measure of germination metabolism, was reduced by less than 1 log. The data indicate that spores can retain the potential to initiate germination-associated metabolic processes and produce biological signature molecules after being rendered nonviable by exposure to Mars solar radiation.
Varnali, Tereza; Edwards, Howell G M
2010-07-13
The recognition that scytonemin, the radiation protectant pigment produced by extremophilic cyanobacterial colonies in stressed terrestrial environments, is a key biomarker for extinct or extant life preserved in geological scenarios is critically important for the detection of life signatures by remote analytical instrumentation on planetary surfaces and subsurfaces. The ExoMars mission to seek life signatures on Mars is just one experiment that will rely upon the detection of molecules such as scytonemin in the Martian regolith. Following a detailed structural analysis of the parent scytonemin, we report here for the first time a similar analysis of several of its methoxy derivatives that have recently been extracted from stressed cyanobacteria. Ab initio calculations have been carried out to determine the most stable molecular configurations, and the implications of the structural changes imposed by the methoxy group additions on the spectral characteristics of the parent molecule are discussed. The calculated electronic absorption bands of the derivative molecules reveal that their capability of removing UVA wavelengths is removed while preserving the ability to absorb the shorter wavelength UVB and UVC radiation, in contrast to scytonemin itself. This is indicative of a special role for these molecules in the protective strategy of the cyanobacterial extremophiles.
In situ survey of life cycle phases of the coccolithophore Emiliania huxleyi (Haptophyta).
Frada, Miguel J; Bidle, Kay D; Probert, Ian; de Vargas, Colomban
2012-06-01
The cosmopolitan coccolithophore Emiliania huxleyi is characterized by a strongly differentiated haplodiplontic life cycle consisting of a diploid phase, generally bearing coccoliths (calcified) but that can be also non-calcified, and a non-calcified biflagellated haploid phase. Given most studies have focused on the bloom-producing calcified phase, there is little-to-no information about non-calcified cells in nature. Using field mesocoms as experimental platforms, we quantitatively surveyed calcified and non-calcified cells using the combined calcareous detection fluorescent in situ hybridization (COD-FISH) method and qualitatively screened for haploid specific transcripts using reverse transcription-PCR during E. huxleyi bloom successions. Diploid, calcified cells formed dense blooms that were followed by the massive proliferation of E. huxleyi viruses (EhVs), which caused bloom demise. Non-calcified cells were also detected throughout the experiment, accounting for a minor fraction of the population but becoming progressively more abundant during mid-late bloom periods concomitant with EhV burst. Non-calcified cell growth also paralleled a distinct window of haploid-specific transcripts and the appearance of autotrophic flagellates morphologically similar to haploid cells, both of which are suggestive of meiosis and sexual life cycling during natural blooms of this prominent marine phytoplankton species. © 2012 Society for Applied Microbiology and Blackwell Publishing Ltd.
The Rate of Crude Oil Biodegradation in the Sea.
Prince, Roger C; Butler, Josh D; Redman, Aaron D
2017-02-07
Various groups have studied the rate of oil biodegradation in the sea over many years, but with no consensus on results. This can be attributed to many factors, but we show here that the principal confounding influence is the concentration of oil used in different experiments. Because of dilution, measured concentrations of dispersed oil in the sea are sub-parts-per-million within a day of dispersal, and at such concentrations the rate of biodegradation of detectable oil hydrocarbons has an apparent half-life of 7-14 days. This can be contrasted with the rate of degradation at the higher concentrations found in oil slicks or when stranded on a shoreline; there the apparent half-life varies from many months to many years.
Laboratory Detection and Analysis of Organic Compounds in Rocks Using HPLC and XRD Methods
NASA Technical Reports Server (NTRS)
Dragoi, D.; Kanik, I.; Bar-Cohen, Y.; Sherrit, S.; Tsapin, A.; Kulleck, J.
2004-01-01
In this work we describe an analytical method for determining the presence of organic compounds in rocks, limestone, and other composite materials. Our preliminary laboratory experiments on different rocks/limestone show that the organic component in mineralogical matrices is a minor phase on order of hundreds of ppm and can be better detected using high precision liquid chromatography (HPLC). The matrix, which is the major phase, plays an important role in embedding and protecting the organic molecules from the harsh Martian environment. Some rocks bear significant amounts of amino acids therefore, it is possible to identify these phases using powder x-ray diffraction (XRD) by crystallizing the organic. The method of detection/analysis of organics, in particular amino acids, that have been associated with life will be shown in the next section.
Application of metal magnetic memory technology on defects detection of jack-up platform
NASA Astrophysics Data System (ADS)
Xu, Changhang; Cheng, Liping; Xie, Jing; Yin, Xiaokang; Chen, Guoming
2016-02-01
Metal magnetic memory test (MMMT), which is an effective way in evaluating early damages of ferrimagnets, can determine the existence of material stresses concentration and premature defects. As one of offshore oil exploration and development equipment, jack-up platform always generate stress concentration during its life-cycle due to complicated loading condition and the hash marine environment, which will decline the bearing capacity and cause serious consequences. The paper conducts in situ experiments of defects detection on some key structural components of jack-up platform using MMMT. The signals acquired by MMM-System are processed for feature extraction to evaluate the severity of structure stress concentration. The results show that the method presented in this paper based on MMMT can provide an effective and convenient way of defect detection and structural health monitoring for Jack-up Platform.
The Viking biological investigation - Preliminary results
NASA Technical Reports Server (NTRS)
Klein, H. P.; Oyama, V. I.; Berdahl, B. J.; Horowitz, N. H.; Hobby, G. L.; Levin, G. V.; Straat, P. A.; Lederberg, J.; Rich, A.; Hubbard, J. S.
1976-01-01
A preliminary progress report is presented for the Viking biological investigation through its first month. The carbon assimilation, gas exchange, and labeled release experiments are described in detail, and the chronology of the experiments is outlined. For the first experiment, it is found that a small amount of gas was converted into organic material in one sample and that heat treatment of a duplicate sample prevented such conversion. In the second experiment, a substantial amount of O2 was detected along with significant increases in CO2 and small changes in N2. In the third experiment, a significant amount of radioactive gas was evolved from one sample, but not from a duplicate heat-treated sample. Possible biological and nonbiological interpretations are considered for these results. It is concluded that while the experiments provide clear evidence for the occurrence of chemical reactions and while the results do not violate any prima facie criteria for biological processes, a definitive answer cannot yet be given to the question of whether life exists on Mars.
2007-08-01
ERDC/TN ANSRP-07-2 August 2007 Detection of Apoptosis in Early Life Stages as a Tool to Evaluate Chemical Control of Invasive Species by J...4. TITLE AND SUBTITLE Detection of Apoptosis in Early Life Stages as a Tool to Evaluate Chemical Control of Invasive Species 5a. CONTRACT NUMBER 5b...heralding apoptosis . Data analysis. An apoptotic index (API) was established by calculating the percentage of embryos in each life stage with
A non-invasive tool for detecting cervical cancer odor by trained scent dogs.
Guerrero-Flores, Héctor; Apresa-García, Teresa; Garay-Villar, Ónix; Sánchez-Pérez, Alejandro; Flores-Villegas, David; Bandera-Calderón, Artfy; García-Palacios, Raúl; Rojas-Sánchez, Teresita; Romero-Morelos, Pablo; Sánchez-Albor, Verónica; Mata, Osvaldo; Arana-Conejo, Víctor; Badillo-Romero, Jesús; Taniguchi, Keiko; Marrero-Rodríguez, Daniel; Mendoza-Rodríguez, Mónica; Rodríguez-Esquivel, Miriam; Huerta-Padilla, Víctor; Martínez-Castillo, Andrea; Hernández-Gallardo, Irma; López-Romero, Ricardo; Bandala, Cindy; Rosales-Guevara, Juan; Salcedo, Mauricio
2017-01-26
Cervical Cancer (CC) has become a public health concern of alarming proportions in many developing countries such as Mexico, particularly in low income sectors and marginalized regions. As such, an early detection is a key medical factor in improving not only their population's quality of life but also its life expectancy. Interestingly, there has been an increase in the number of reports describing successful attempts at detecting cancer cells in human tissues or fluids using trained (sniffer) dogs. The great odor detection threshold exhibited by dogs is not unheard of. However, this represented a potential opportunity to develop an affordable, accessible, and non-invasive method for detection of CC. Using clicker training, a male beagle was trained to recognize CC odor. During training, fresh CC biopsies were used as a reference point. Other samples used included cervical smears on glass slides and medical surgical bandages used as intimate sanitary pads by CC patients. A double-blind procedure was exercised when testing the beagle's ability to discriminate CC from control samples. The beagle was proven able to detect CC-specific volatile organic compounds (VOC) contained in both fresh cervical smear samples and adsorbent material samples. Beagle's success rate at detecting and discriminating CC and non-CC odors, as indicated by specificity and sensitivity values recorded during the experiment, stood at an overall high (>90%). CC-related VOC in adsorbent materials were detectable after only eight hours of use by CC patients. Present data suggests different applications for VOC from the uterine cervix to be used in the detection and diagnosis of CC. Furthermore, data supports the use of trained dogs as a viable, affordable, non-invasive and, therefore, highly relevant alternative method for detection of CC lesions. Additional benefits of this method include its quick turnaround time and ease of use while remaining highly accurate and robust.
NASA Technical Reports Server (NTRS)
Glavin, Daniel P.; Dworkin, Jason P.; Lupisella, Mark; Kminek, Gerhard; Rummel, John D.
2010-01-01
NASA and ESA have outlined visions for solar system exploration that will include a series of lunar robotic precursor missions to prepare for, and support a human return to the Moon, and future human exploration of Mars and other destinations. One of the guiding principles for exploration is to pursue compelling scientific questions about the origin and evolution of life. The search for life on objects such as Mars will require that all spacecraft and instrumentation be sufficiently cleaned and sterilized prior to launch to ensure that the scientific integrity of extraterrestrial samples is not jeopardized by terrestrial organic contamination. Under the Committee on Space Research's (COSPAR's) current planetary protection policy for the Moon, no sterilization procedures are required for outbound lunar spacecraft, nor is there yet a planetary protection category for human missions. Future in situ investigations of a variety of locations on the Moon by highly sensitive instruments designed to search for biologically derived organic compounds would help assess the contamination of the Moon by lunar spacecraft. These studies could also provide valuable "ground truth" data for Mars sample return missions and help define planetary protection requirements for future Mars bound spacecraft carrying life detection experiments. In addition, studies of the impact of terrestrial contamination of the lunar surface by the Apollo astronauts could provide valuable data to help refine future Mars surface exploration plans for a human mission to Mars.
Robotic Astrobiology: Searching for Life with Rovers
NASA Astrophysics Data System (ADS)
Cabrol, N. A.; Wettergreen, D. S.; Team, L.
2006-05-01
The Life In The Atacama (LITA) project has developed and field tested a long-range, solar-powered, automated rover platform (Zoe) and a science payload assembled to search for microbial life in the Atacama desert. Life is hardly detectable over most of the extent of the driest desert on Earth. Its geological, climatic, and biological evolution provides a unique training ground for designing and testing exploration strategies and life detection methods for the robotic search for life on Mars. LITA opens the path to a new generation of rover missions that will transition from the current study of habitability (MER) to the upcoming search for, and study of, habitats and life on Mars. Zoe's science payload reflects this transition by combining complementary elements, some directed towards the remote sensing of the environment (geology, morphology, mineralogy, weather/climate) for the detection of conditions favorable to microbial habitats and oases along survey traverses, others directed toward the in situ detection of life' signatures (biological and physical, such as biological constructs and patterns). New exploration strategies specifically adapted to the search for microbial life were designed and successfully tested in the Atacama between 2003-2005. They required the development and implementation in the field of new technological capabilities, including navigation beyond the horizon, obstacle avoidance, and "science-on-the-fly" (automated detection of targets of science value), and that of new rover planning tools in the remote science operation center.
Ways that Social Change Predicts Personal Quality of Life
ERIC Educational Resources Information Center
Cheung, Chau-Kiu; Leung, Kwok
2010-01-01
A notable way that social change affects personal quality of life would rely on the person's experience with social change. This experience may influence societal quality of life and quality of work life, which may in turn affect personal quality of life. Additionally, the experience of social change is possibly less detrimental to personal…
[Day surgery in breast reconstructive surgery: our experience].
Fierro, N; D'Ermo, G; Barbetti, E; Mazza, E; Gallinaro, L S; Amanti, C; De Biasio, G; Galassi, G; Galassi, G
2004-10-01
Breast cancer is the most common tumour in Italy in the female population, counting for about 40000 new cases every year. The psychological aspects of breast mutilation and the social and economic implications are receiving increasing attention. Despite of the diffusion of screening programs to detect pre-clinical breast cancers, 30% of patients still undergo radical interventions. Therefore, many women present serious limitations of their social-life that can lead to severe depression since, in occidental countries, the biological function of the breast is less considered than its primary role of femininity and sexuality. The gold-standard is to conceal oncological radicality and aesthetic preservation. The Authors present their experience analysing the techniques employed.
Enzyme-Cascade Analysis of the Rio Tinto Subsurface Environment: A Biosensor Experiment
NASA Technical Reports Server (NTRS)
McKay, David S.; Lynch, Kennda; Wainwright, Norman; Child, Alice; Williams, Kendra; McKay, David; Amils, Ricardo; Gonzalez, Elena; Stoker, Carol
2004-01-01
The Portable Test System (PTS), designed & developed by Charles Rivers Laboratories, Inc. (Charleston, SC) is a portable instrument that was designed to perform analysis of enzymatic assays related to rapid assessment of microbial contamination (Wainwright, 2003). The enzymatic cascade of Limulus Amebocyte Lysate (LAL) is known to be one of the most sensitive techniques available for microbial detection, enabling the PTS to be evaluated as a potential life detection instrument for in situ Astrobiology missions. In the summer of 2003 the system was tested as a part of the Mars Astrobiology Research and Technology Experiment (MARTE) ground truth science campaign in the Rio Tinto Analogue environment near Nerva, Spain. The preliminary results show that the PTS analysis correlates well with the contamination control tests and the more traditional lab-based biological assays performed during the MARTE field mission. Further work will be conducted on this research during a second field campaign in 2004 and a technology demonstration of a prototype instrument that includes autonomous sample preparation will occur in 2005.
Detection of non-coding RNA in bacteria and archaea using the DETR'PROK Galaxy pipeline.
Toffano-Nioche, Claire; Luo, Yufei; Kuchly, Claire; Wallon, Claire; Steinbach, Delphine; Zytnicki, Matthias; Jacq, Annick; Gautheret, Daniel
2013-09-01
RNA-seq experiments are now routinely used for the large scale sequencing of transcripts. In bacteria or archaea, such deep sequencing experiments typically produce 10-50 million fragments that cover most of the genome, including intergenic regions. In this context, the precise delineation of the non-coding elements is challenging. Non-coding elements include untranslated regions (UTRs) of mRNAs, independent small RNA genes (sRNAs) and transcripts produced from the antisense strand of genes (asRNA). Here we present a computational pipeline (DETR'PROK: detection of ncRNAs in prokaryotes) based on the Galaxy framework that takes as input a mapping of deep sequencing reads and performs successive steps of clustering, comparison with existing annotation and identification of transcribed non-coding fragments classified into putative 5' UTRs, sRNAs and asRNAs. We provide a step-by-step description of the protocol using real-life example data sets from Vibrio splendidus and Escherichia coli. Copyright © 2013 The Authors. Published by Elsevier Inc. All rights reserved.
Wepfer, Ariane G; Brauchli, Rebecca; Jenny, Gregor J; Hämmig, Oliver; Bauer, Georg F
2015-12-24
The division of paid and unpaid labor in families continues to be highly gendered with men doing more paid work and women doing more unpaid care work. This is especially true for life stages with young children. Our study investigates the subjective experience of demands in the work and the private domain and the experience of work-life balance across family-life stages as a consequence of this gendered division of labor. We used data from a survey study on work-life issues and health in four large companies in Switzerland (N = 3664). In line with our hypotheses, subjective work and private demands were predicted by an interaction of family-life stages and gender. Specifically, during the primary child-rearing family-life stages, women experience more private demands than men while men experience more work demands, regardless of level of employment. Furthermore, women who work part time experience more work-life balance than women who work full time and more than men who work part or full time during the primary child-rearing family-life stages. Results are discussed in terms of a gendered work-life experience across the life course and the need for part-time work for both genders. Finally, conclusions are drawn concerning our results' implications for public health considerations.
Lipase-nanoporous gold biocomposite modified electrode for reliable detection of triglycerides.
Wu, Chao; Liu, Xueying; Li, Yufei; Du, Xiaoyu; Wang, Xia; Xu, Ping
2014-03-15
For triglycerides biosensor design, protein immobilization is necessary to create the interface between the enzyme and the electrode. In this study, a glassy carbon electrode (GCE) was modified with lipase-nanoporous gold (NPG) biocomposite (denoted as lipase/NPG/GCE). Due to highly conductive, porous, and biocompatible three-dimensional structure, NPG is suitable for enzyme immobilization. In cyclic voltammetry experiments, the lipase/NPG/GCE bioelectrode displayed surface-confined reaction in a phosphate buffer solution. Linear responses were obtained for tributyrin concentrations ranging from 50 to 250 mg dl(-1) and olive oil concentrations ranging from 10 to 200 mg dl(-1). The value of apparent Michaelis-Menten constant for tributyrin was 10.67 mg dl(-1) and the detection limit was 2.68 mg dl(-1). Further, the lipase/NPG/GCE bioelectrode had strong anti-interference ability against urea, glucose, cholesterol, and uric acid as well as a long shelf-life. For the detection of triglycerides in human serum, the values given by the lipase/NPG/GCE bioelectrode were in good agreement with those of an automatic biochemical analyzer. These properties along with a long self-life make the lipase/NPG/GCE bioelectrode an excellent choice for the construction of triglycerides biosensor. © 2013 Elsevier B.V. All rights reserved.
To call a cloud 'cirrus': sound symbolism in names for categories or items.
Ković, Vanja; Sučević, Jelena; Styles, Suzy J
2017-01-01
The aim of the present paper is to experimentally test whether sound symbolism has selective effects on labels with different ranges-of-reference within a simple noun-hierarchy. In two experiments, adult participants learned the make up of two categories of unfamiliar objects ('alien life forms'), and were passively exposed to either category-labels or item-labels, in a learning-by-guessing categorization task. Following category training, participants were tested on their visual discrimination of object pairs. For different groups of participants, the labels were either congruent or incongruent with the objects. In Experiment 1, when trained on items with individual labels, participants were worse (made more errors) at detecting visual object mismatches when trained labels were incongruent. In Experiment 2, when participants were trained on items in labelled categories, participants were faster at detecting a match if the trained labels were congruent, and faster at detecting a mismatch if the trained labels were incongruent. This pattern of results suggests that sound symbolism in category labels facilitates later similarity judgments when congruent, and discrimination when incongruent, whereas for item labels incongruence generates error in judgements of visual object differences. These findings reveal that sound symbolic congruence has a different outcome at different levels of labelling within a noun hierarchy. These effects emerged in the absence of the label itself, indicating subtle but pervasive effects on visual object processing.
Automatic discrimination of fine roots in minirhizotron images.
Zeng, Guang; Birchfield, Stanley T; Wells, Christina E
2008-01-01
Minirhizotrons provide detailed information on the production, life history and mortality of fine roots. However, manual processing of minirhizotron images is time-consuming, limiting the number and size of experiments that can reasonably be analysed. Previously, an algorithm was developed to automatically detect and measure individual roots in minirhizotron images. Here, species-specific root classifiers were developed to discriminate detected roots from bright background artifacts. Classifiers were developed from training images of peach (Prunus persica), freeman maple (Acer x freemanii) and sweetbay magnolia (Magnolia virginiana) using the Adaboost algorithm. True- and false-positive rates for classifiers were estimated using receiver operating characteristic curves. Classifiers gave true positive rates of 89-94% and false positive rates of 3-7% when applied to nontraining images of the species for which they were developed. The application of a classifier trained on one species to images from another species resulted in little or no reduction in accuracy. These results suggest that a single root classifier can be used to distinguish roots from background objects across multiple minirhizotron experiments. By incorporating root detection and discrimination algorithms into an open-source minirhizotron image analysis application, many analysis tasks that are currently performed by hand can be automated.
Evolution of organic molecules under Mars-like UV radiation conditions in space and laboratory
NASA Astrophysics Data System (ADS)
Rouquette, L.; Stalport, F.; Cottin, H.; Coll, P.; Szopa, C.; Saiagh, K.; Poch, O.; Khalaf, D.; Chaput, D.; Grira, K.; Dequaire, T.
2017-09-01
The detection and identification of organic molecules at Mars are of prime importance, as some of these molecules are life precursors and components. While in situ planetary missions are searching for them, it is essential to understand how organic molecules evolve and are preserved at the surface of Mars. Indeed the harsh conditions of the environment of Mars such as ultraviolet (UV) radiation or oxidative processes could explain the low abundance and diversity of organic molecules detected by now [1]. In order to get a better understanding of the evolution of organic matter at the surface of Mars, we exposed organic molecules under a Mars-like UV radiation environment. Similar organic samples were exposed to the Sun radiation, outside the International Space Station (ISS), and under a UV lamp (martian pressure and temperature conditions) in the laboratory. In both experiments, organic molecules tend to photodegrade under Mars-like UV radiation. Minerals, depending on their nature, can protect or accelerate the degradation of organic molecules. For some molecules, new products, possibly photoresistant, seem to be produced. Finally, experimenting in space allow us to get close to in situ conditions and to validate our laboratory experiment while the laboratory experiment is essential to study the evolution of a large amount and diversity of organic molecules.
Determining the inventory impact of extended-shelf-life platelets with a network simulation model.
Blake, John T
2017-12-01
The regulatory shelf life for platelets (PLTs) in many jurisdictions is 5 days. PLT shelf life can be extended to 7 days with an enhanced bacterial detection algorithm. Enhanced testing, however, comes at a cost, which may be offset by reductions in wastage due to longer shelf life. This article describes a method for estimating systemwide reductions in PLT outdates after PLT shelf life is extended. A simulation was used to evaluate the impact of an extended PLT shelf life within a national blood network. A network model of the Canadian Blood Services PLT supply chain was built and validated. PLT shelf life was extended from 5 days to 6, 7, and 8 days and runs were completed to determine the impact on outdates. Results suggest that, in general, a 16.3% reduction in PLT wastage can be expected with each additional day that PLT shelf life is extended. Both suppliers and hospitals will experience fewer outdating units, but wastage will decrease at a faster rate at hospitals. No effect was seen by blood group, but there was some evidence that supplier site characteristics influences both the number of units wasted and the site's ability to benefit from extended-shelf-life PLTs. Extended-shelf-life PLTs will reduce wastage within a blood supply chain. At 7 days, an improvement of 38% reduction in wastage can be expected with outdates being equally distributed between suppliers and hospital customers. © 2017 AABB.
Background-free search for neutrinoless double-β decay of 76Ge with GERDA.
2017-04-05
Many extensions of the Standard Model of particle physics explain the dominance of matter over antimatter in our Universe by neutrinos being their own antiparticles. This would imply the existence of neutrinoless double-β decay, which is an extremely rare lepton-number-violating radioactive decay process whose detection requires the utmost background suppression. Among the programmes that aim to detect this decay, the GERDA Collaboration is searching for neutrinoless double-β decay of 76 Ge by operating bare detectors, made of germanium with an enriched 76 Ge fraction, in liquid argon. After having completed Phase I of data taking, we have recently launched Phase II. Here we report that in GERDA Phase II we have achieved a background level of approximately 10 -3 counts keV -1 kg -1 yr -1 . This implies that the experiment is background-free, even when increasing the exposure up to design level. This is achieved by use of an active veto system, superior germanium detector energy resolution and improved background recognition of our new detectors. No signal of neutrinoless double-β decay was found when Phase I and Phase II data were combined, and we deduce a lower-limit half-life of 5.3 × 10 25 years at the 90 per cent confidence level. Our half-life sensitivity of 4.0 × 10 25 years is competitive with the best experiments that use a substantially larger isotope mass. The potential of an essentially background-free search for neutrinoless double-β decay will facilitate a larger germanium experiment with sensitivity levels that will bring us closer to clarifying whether neutrinos are their own antiparticles.
Background-free search for neutrinoless double-β decay of 76Ge with GERDA
NASA Astrophysics Data System (ADS)
Agostini, M.; Allardt, M.; Bakalyarov, A. M.; Balata, M.; Barabanov, I.; Baudis, L.; Bauer, C.; Bellotti, E.; Belogurov, S.; Belyaev, S. T.; Benato, G.; Bettini, A.; Bezrukov, L.; Bode, T.; Borowicz, D.; Brudanin, V.; Brugnera, R.; Caldwell, A.; Cattadori, C.; Chernogorov, A.; D'Andrea, V.; Demidova, E. V.; di Marco, N.; di Vacri, A.; Domula, A.; Doroshkevich, E.; Egorov, V.; Falkenstein, R.; Fedorova, O.; Freund, K.; Frodyma, N.; Gangapshev, A.; Garfagnini, A.; Gooch, C.; Grabmayr, P.; Gurentsov, V.; Gusev, K.; Hakenmüller, J.; Hegai, A.; Heisel, M.; Hemmer, S.; Hofmann, W.; Hult, M.; Inzhechik, L. V.; Janicskó Csáthy, J.; Jochum, J.; Junker, M.; Kazalov, V.; Kihm, T.; Kirpichnikov, I. V.; Kirsch, A.; Kish, A.; Klimenko, A.; Kneißl, R.; Knöpfle, K. T.; Kochetov, O.; Kornoukhov, V. N.; Kuzminov, V. V.; Laubenstein, M.; Lazzaro, A.; Lebedev, V. I.; Lehnert, B.; Liao, H. Y.; Lindner, M.; Lippi, I.; Lubashevskiy, A.; Lubsandorzhiev, B.; Lutter, G.; Macolino, C.; Majorovits, B.; Maneschg, W.; Medinaceli, E.; Miloradovic, M.; Mingazheva, R.; Misiaszek, M.; Moseev, P.; Nemchenok, I.; Palioselitis, D.; Panas, K.; Pandola, L.; Pelczar, K.; Pullia, A.; Riboldi, S.; Rumyantseva, N.; Sada, C.; Salamida, F.; Salathe, M.; Schmitt, C.; Schneider, B.; Schönert, S.; Schreiner, J.; Schulz, O.; Schütz, A.-K.; Schwingenheuer, B.; Selivanenko, O.; Shevchik, E.; Shirchenko, M.; Simgen, H.; Smolnikov, A.; Stanco, L.; Vanhoefer, L.; Vasenko, A. A.; Veresnikova, A.; von Sturm, K.; Wagner, V.; Walter, M.; Wegmann, A.; Wester, T.; Wiesinger, C.; Wojcik, M.; Yanovich, E.; Zhitnikov, I.; Zhukov, S. V.; Zinatulina, D.; Zuber, K.; Zuzel, G.; GERDA Collaboration
2017-04-01
Many extensions of the Standard Model of particle physics explain the dominance of matter over antimatter in our Universe by neutrinos being their own antiparticles. This would imply the existence of neutrinoless double-β decay, which is an extremely rare lepton-number-violating radioactive decay process whose detection requires the utmost background suppression. Among the programmes that aim to detect this decay, the GERDA Collaboration is searching for neutrinoless double-β decay of 76Ge by operating bare detectors, made of germanium with an enriched 76Ge fraction, in liquid argon. After having completed Phase I of data taking, we have recently launched Phase II. Here we report that in GERDA Phase II we have achieved a background level of approximately 10-3 counts keV-1 kg-1 yr-1. This implies that the experiment is background-free, even when increasing the exposure up to design level. This is achieved by use of an active veto system, superior germanium detector energy resolution and improved background recognition of our new detectors. No signal of neutrinoless double-β decay was found when Phase I and Phase II data were combined, and we deduce a lower-limit half-life of 5.3 × 1025 years at the 90 per cent confidence level. Our half-life sensitivity of 4.0 × 1025 years is competitive with the best experiments that use a substantially larger isotope mass. The potential of an essentially background-free search for neutrinoless double-β decay will facilitate a larger germanium experiment with sensitivity levels that will bring us closer to clarifying whether neutrinos are their own antiparticles.
State-of-the-art Instruments for Detecting Extraterrestrial Life
NASA Technical Reports Server (NTRS)
Bada, Jeffrey L.
2003-01-01
In the coming decades, state-of-the-art spacecraft-based instruments that can detect key components associated with life as we know it on Earth will directly search for extinct or extant extraterrestrial life in our solar system. Advances in our analytical and detection capabilities, especially those based on microscale technologies, will be important in enhancing the abilities of these instruments. Remote sensing investigations of the atmospheres of extrasolar planets could provide evidence of photosynthetic-based life outside our solar system, although less advanced life will remain undetectable by these methods. Finding evidence of extraterrestrial life would have profound consequences both with respect to our understanding of chemical and biological evolution, and whether the biochemistry on Earth is unique in the universe.
Temporal Audiovisual Motion Prediction in 2D- vs. 3D-Environments
Dittrich, Sandra; Noesselt, Tömme
2018-01-01
Predicting motion is essential for many everyday life activities, e.g., in road traffic. Previous studies on motion prediction failed to find consistent results, which might be due to the use of very different stimulus material and behavioural tasks. Here, we directly tested the influence of task (detection, extrapolation) and stimulus features (visual vs. audiovisual and three-dimensional vs. non-three-dimensional) on temporal motion prediction in two psychophysical experiments. In both experiments a ball followed a trajectory toward the observer and temporarily disappeared behind an occluder. In audiovisual conditions a moving white noise (congruent or non-congruent to visual motion direction) was presented concurrently. In experiment 1 the ball reappeared on a predictable or a non-predictable trajectory and participants detected when the ball reappeared. In experiment 2 the ball did not reappear after occlusion and participants judged when the ball would reach a specified position at two possible distances from the occluder (extrapolation task). Both experiments were conducted in three-dimensional space (using stereoscopic screen and polarised glasses) and also without stereoscopic presentation. Participants benefitted from visually predictable trajectories and concurrent sounds during detection. Additionally, visual facilitation was more pronounced for non-3D stimulation during detection task. In contrast, for a more complex extrapolation task group mean results indicated that auditory information impaired motion prediction. However, a post hoc cross-validation procedure (split-half) revealed that participants varied in their ability to use sounds during motion extrapolation. Most participants selectively profited from either near or far extrapolation distances but were impaired for the other one. We propose that interindividual differences in extrapolation efficiency might be the mechanism governing this effect. Together, our results indicate that both a realistic experimental environment and subject-specific differences modulate the ability of audiovisual motion prediction and need to be considered in future research. PMID:29618999
Temporal Audiovisual Motion Prediction in 2D- vs. 3D-Environments.
Dittrich, Sandra; Noesselt, Tömme
2018-01-01
Predicting motion is essential for many everyday life activities, e.g., in road traffic. Previous studies on motion prediction failed to find consistent results, which might be due to the use of very different stimulus material and behavioural tasks. Here, we directly tested the influence of task (detection, extrapolation) and stimulus features (visual vs. audiovisual and three-dimensional vs. non-three-dimensional) on temporal motion prediction in two psychophysical experiments. In both experiments a ball followed a trajectory toward the observer and temporarily disappeared behind an occluder. In audiovisual conditions a moving white noise (congruent or non-congruent to visual motion direction) was presented concurrently. In experiment 1 the ball reappeared on a predictable or a non-predictable trajectory and participants detected when the ball reappeared. In experiment 2 the ball did not reappear after occlusion and participants judged when the ball would reach a specified position at two possible distances from the occluder (extrapolation task). Both experiments were conducted in three-dimensional space (using stereoscopic screen and polarised glasses) and also without stereoscopic presentation. Participants benefitted from visually predictable trajectories and concurrent sounds during detection. Additionally, visual facilitation was more pronounced for non-3D stimulation during detection task. In contrast, for a more complex extrapolation task group mean results indicated that auditory information impaired motion prediction. However, a post hoc cross-validation procedure (split-half) revealed that participants varied in their ability to use sounds during motion extrapolation. Most participants selectively profited from either near or far extrapolation distances but were impaired for the other one. We propose that interindividual differences in extrapolation efficiency might be the mechanism governing this effect. Together, our results indicate that both a realistic experimental environment and subject-specific differences modulate the ability of audiovisual motion prediction and need to be considered in future research.
The future of spectroscopic life detection on exoplanets
Seager, Sara
2014-01-01
The discovery and characterization of exoplanets have the potential to offer the world one of the most impactful findings ever in the history of astronomy—the identification of life beyond Earth. Life can be inferred by the presence of atmospheric biosignature gases—gases produced by life that can accumulate to detectable levels in an exoplanet atmosphere. Detection will be made by remote sensing by sophisticated space telescopes. The conviction that biosignature gases will actually be detected in the future is moderated by lessons learned from the dozens of exoplanet atmospheres studied in last decade, namely the difficulty in robustly identifying molecules, the possible interference of clouds, and the permanent limitations from a spectrum of spatially unresolved and globally mixed gases without direct surface observations. The vision for the path to assess the presence of life beyond Earth is being established. PMID:25092345
The future of spectroscopic life detection on exoplanets.
Seager, Sara
2014-09-02
The discovery and characterization of exoplanets have the potential to offer the world one of the most impactful findings ever in the history of astronomy--the identification of life beyond Earth. Life can be inferred by the presence of atmospheric biosignature gases--gases produced by life that can accumulate to detectable levels in an exoplanet atmosphere. Detection will be made by remote sensing by sophisticated space telescopes. The conviction that biosignature gases will actually be detected in the future is moderated by lessons learned from the dozens of exoplanet atmospheres studied in last decade, namely the difficulty in robustly identifying molecules, the possible interference of clouds, and the permanent limitations from a spectrum of spatially unresolved and globally mixed gases without direct surface observations. The vision for the path to assess the presence of life beyond Earth is being established.
NASA Technical Reports Server (NTRS)
Cabrol, N. A.a; Wettergreen, D. S.; Whittaker, R.; Grin, E. A.; Moersch, J.; Diaz, G. Chong; Cockell, C.; Coppin, P.; Dohm, J. M.; Fisher, G.
2005-01-01
The Life In The Atacama (LITA) project develops and field tests a long-range, solarpowered, automated rover platform (Zo ) and a science payload assembled to search for microbial life in the Atacama desert. Life is barely detectable over most of the driest desert on Earth. Its unique geological, climatic, and biological evolution have created a unique training site for designing and testing exploration strategies and life detection methods for the robotic search for life on Mars.
Storrie-Lombardi, Michael C; Muller, Jan-Peter; Fisk, Martin R; Cousins, Claire; Sattler, Birgit; Griffiths, Andrew D; Coates, Andrew J
2009-12-01
The European Space Agency will launch the ExoMars mission in 2016 with a primary goal of surveying the martian subsurface for evidence of organic material. We have recently investigated the utility of including either a 365 nm light-emitting diode or a 375 nm laser light source in the ExoMars rover panoramic camera (PanCam). Such a modification would make it feasible to monitor rover drill cuttings optically for the fluorescence signatures of aromatic organic molecules and map the distribution of polycyclic aromatic hydrocarbons (PAHs) as a function of depth to the 2 m limit of the ExoMars drill. The technique described requires no sample preparation, does not consume irreplaceable resources, and would allow mission control to prioritize deployment of organic detection experiments that require sample destruction, expenditure of non-replaceable consumables, or both. We report here for the first time laser-induced fluorescence emission (L.I.F.E.) imaging detection limits for anthracene, pyrene, and perylene targets doped onto a Mars analog granular peridotite with a 375 nm Nichia laser diode in optically uncorrected wide-angle mode. Data were collected via the Beagle 2 PanCam backup filter wheel fitted with original blue (440 nm), green (530 nm), and red (670 nm) filters. All three PAH species can be detected with the PanCam green (530 nm) filter. Detection limits in the green band for signal-to-noise ratios (S/N) > 10 are 49 parts per million (ppm) for anthracene, 145 ppm for pyrene, and 20 ppm for perylene. The anthracene detection limit improves to 7 ppm with use of the PanCam blue filter. We discuss soil-dependent detection limit constraints; use of UV excitation with other rover cameras, which provides higher spatial resolution; and the advantages of focused and wide-angle laser modes. Finally, we discuss application of L.I.F.E. techniques at multiple wavelengths for exploration of Mars analog extreme environments on Earth, including Icelandic hydrothermally altered basalts and the ice-covered lakes and glaciers of Dronning Maud Land, Antarctica.
Fracture Mechanics Analysis of LH2 Feed Line Flow Liners
NASA Technical Reports Server (NTRS)
James, Mark A.; Dawicke, David S.; Brzowski, Matthew B.; Raju, Ivatury S.; Elliott, Kenny B.; Harris, Charles E.
2006-01-01
Inspections of the Space Shuttle Main Engine revealed fatigue cracks growing from slots in the flow liner of the liquid hydrogen (LH2) feed lines. During flight, the flow liners experience complex loading induced by flow of LH2 and the resonance characteristics of the structure. The flow liners are made of Inconel 718 and had previously not been considered a fracture critical component. However, fatigue failure of a flow liner could have catastrophic effect on the Shuttle engines. A fracture mechanics study was performed to determine if a damage tolerance approach to life management was possible and to determine the sensitivity to the load spectra, material properties, and crack size. The load spectra were derived separately from ground tests and material properties were obtained from coupon tests. The stress-intensity factors for the fatigue cracks were determined from a shell-dynamics approach that simulated the dominant resonant frequencies. Life predictions were obtained using the NASGRO life prediction code. The results indicated that adequate life could not be demonstrated for initial crack lengths of the size that could be detected by traditional NDE techniques.
[Isolated congenital anosmia--clinical and daily life aspects of a life without a sense of smell].
Bojanowski, V; Hummel, T; Croy, I
2013-01-01
Isolated congenital anosmia is a disorder (ICA) characterized by not or only rudimentary developed central olfactory structures. This results in the lack of the sense of smell since birth. Although this phenomenon is known among clinicians almost no knowledge exists on how those people cope with the disorder. 43 people with ICA were asked with a standardised questionnaire about when they fi rst noticed their disorder, how they experience the lack of smelling ability and about different aspects of daily life. ICA is detected by the patients self or by their parents at the age of 10 in average. However about 13 years pass, until the right diagnosis is confirmed. In contrast to people with acquired olfactory loos ICA patients have developed strategies to adapt to the deficit in daily life. Nevertheless they report increased social insecurity and more hazardous events. The results can be of advantage for clinicians and patients to get a better understanding of the disorder. © Georg Thieme Verlag KG Stuttgart · New York.
Prins, Theo W; van Dijk, Jeroen P; Beenen, Henriek G; Van Hoef, AM Angeline; Voorhuijzen, Marleen M; Schoen, Cor D; Aarts, Henk JM; Kok, Esther J
2008-01-01
Background To maintain EU GMO regulations, producers of new GM crop varieties need to supply an event-specific method for the new variety. As a result methods are nowadays available for EU-authorised genetically modified organisms (GMOs), but only to a limited extent for EU-non-authorised GMOs (NAGs). In the last decade the diversity of genetically modified (GM) ingredients in food and feed has increased significantly. As a result of this increase GMO laboratories currently need to apply many different methods to establish to potential presence of NAGs in raw materials and complex derived products. Results In this paper we present an innovative method for detecting (approved) GMOs as well as the potential presence of NAGs in complex DNA samples containing different crop species. An optimised protocol has been developed for padlock probe ligation in combination with microarray detection (PPLMD) that can easily be scaled up. Linear padlock probes targeted against GMO-events, -elements and -species have been developed that can hybridise to their genomic target DNA and are visualised using microarray hybridisation. In a tenplex PPLMD experiment, different genomic targets in Roundup-Ready soya, MON1445 cotton and Bt176 maize were detected down to at least 1%. In single experiments, the targets were detected down to 0.1%, i.e. comparable to standard qPCR. Conclusion Compared to currently available methods this is a significant step forward towards multiplex detection in complex raw materials and derived products. It is shown that the PPLMD approach is suitable for large-scale detection of GMOs in real-life samples and provides the possibility to detect and/or identify NAGs that would otherwise remain undetected. PMID:19055784
Prins, Theo W; van Dijk, Jeroen P; Beenen, Henriek G; Van Hoef, Am Angeline; Voorhuijzen, Marleen M; Schoen, Cor D; Aarts, Henk J M; Kok, Esther J
2008-12-04
To maintain EU GMO regulations, producers of new GM crop varieties need to supply an event-specific method for the new variety. As a result methods are nowadays available for EU-authorised genetically modified organisms (GMOs), but only to a limited extent for EU-non-authorised GMOs (NAGs). In the last decade the diversity of genetically modified (GM) ingredients in food and feed has increased significantly. As a result of this increase GMO laboratories currently need to apply many different methods to establish to potential presence of NAGs in raw materials and complex derived products. In this paper we present an innovative method for detecting (approved) GMOs as well as the potential presence of NAGs in complex DNA samples containing different crop species. An optimised protocol has been developed for padlock probe ligation in combination with microarray detection (PPLMD) that can easily be scaled up. Linear padlock probes targeted against GMO-events, -elements and -species have been developed that can hybridise to their genomic target DNA and are visualised using microarray hybridisation.In a tenplex PPLMD experiment, different genomic targets in Roundup-Ready soya, MON1445 cotton and Bt176 maize were detected down to at least 1%. In single experiments, the targets were detected down to 0.1%, i.e. comparable to standard qPCR. Compared to currently available methods this is a significant step forward towards multiplex detection in complex raw materials and derived products. It is shown that the PPLMD approach is suitable for large-scale detection of GMOs in real-life samples and provides the possibility to detect and/or identify NAGs that would otherwise remain undetected.
The mechanism of valence-space metaphors: ERP evidence for affective word processing.
Xie, Jiushu; Wang, Ruiming; Chang, Song
2014-01-01
Embodied cognition contends that the representation and processing of concepts involve perceptual, somatosensory, motoric, and other physical re-experiencing information. In this view, affective concepts are also grounded in physical information. For instance, people often say "feeling down" or "cheer up" in daily life. These phrases use spatial information to understand affective concepts. This process is referred to as valence-space metaphor. Valence-space metaphors refer to the employment of spatial information (lower/higher space) to elaborate affective concepts (negative/positive concepts). Previous studies have demonstrated that processing affective words affects performance on a spatial detection task. However, the mechanism(s) behind this effect remain unclear. In the current study, we hypothesized that processing affective words might produce spatial information. Consequently, spatial information would affect the following spatial cue detection/discrimination task. In Experiment 1, participants were asked to remember an affective word. Then, they completed a spatial cue detection task while event-related potentials were recorded. The results indicated that the top cues induced enhanced amplitude of P200 component while participants kept positive words relative to negative words in mind. On the contrary, the bottom cues induced enhanced P200 amplitudes while participants kept negative words relative to positive words in mind. In Experiment 2, we conducted a behavioral experiment that employed a similar paradigm to Experiment 1, but used arrows instead of dots to test the attentional nature of the valence-space metaphor. We found a similar facilitation effect as found in Experiment 1. Positive words facilitated the discrimination of upper arrows, whereas negative words facilitated the discrimination of lower arrows. In summary, affective words might activate spatial information and cause participants to allocate their attention to corresponding locations. Valence-space metaphors might be grounded in attention allocation.
Study on thin wideband applicator for detecting blood characteristics in human body
NASA Astrophysics Data System (ADS)
Bamba, Kazuki; Kuki, Takao; Nikawa, Yoshio
2016-11-01
Preventive care as well as early detection method and monitoring technique for diseases are highly attracted attention to increase quality of life. Noninvasive measurement method for blood characteristics in body is expected by patients with kidney dysfunction. Complex permittivity of blood is changed a few present at 6GHz. This change is caused by the change of water and albumin contents in blood. In this study, to detect blood characteristics in human body, experiments with phantom model has been performed using thin wideband applicator for examining microwave transmission up to 6GHz. The thin wideband applicator has advantages for detecting living body information in detail. The thin wideband applicator is designed based on Antipodal Vivaldi Antenna and is not required any balun and is very easy handling. Using developed Antipodal Vivaldi Antenna, transmission coefficient can be obtained as a function of thickness of phantom model with high sensitivity. Using this method, highly sensitive sensor for obtaining characteristics of blood in body can be developed.
Modeling inter-signal arrival times for accurate detection of CAN bus signal injection attacks
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moore, Michael Roy; Bridges, Robert A; Combs, Frank L
Modern vehicles rely on hundreds of on-board electronic control units (ECUs) communicating over in-vehicle networks. As external interfaces to the car control networks (such as the on-board diagnostic (OBD) port, auxiliary media ports, etc.) become common, and vehicle-to-vehicle / vehicle-to-infrastructure technology is in the near future, the attack surface for vehicles grows, exposing control networks to potentially life-critical attacks. This paper addresses the need for securing the CAN bus by detecting anomalous traffic patterns via unusual refresh rates of certain commands. While previous works have identified signal frequency as an important feature for CAN bus intrusion detection, this paper providesmore » the first such algorithm with experiments on five attack scenarios. Our data-driven anomaly detection algorithm requires only five seconds of training time (on normal data) and achieves true positive / false discovery rates of 0.9998/0.00298, respectively (micro-averaged across the five experimental tests).« less
NASA Technical Reports Server (NTRS)
Carle, G. C.
1985-01-01
Gas chromatography (GC) technology was developed for flight experiments in solar system exploration. The GC is a powerful analytical technique with simple devices separating individual components from complex mixtures to make very sensitive quantitative and qualitative measurements. It monitors samples containing mixtures of fixed gases and volatile organic molecules. The GC was used on the Viking mission in support of life detection experiments and on the Pioneer Venus Large Probe to determine the composition of the venusian atmosphere. A flight GC is under development to study the progress and extent of STS astronaut denitrogenation prior to extravehicular activity. Advanced flight GC concepts and systems for future solar system exploration are also studied. Studies include miniature ionization detectors and associated control systems capable of detecting from ppb up to 100% concentration levels. Further miniaturization is investigated using photolithography and controlled chemical etching in silicon wafers. Novel concepts such as ion mobility drift spectroscopy and multiplex gas chromatography are also developed for future flight experiments. These powerful analytical concepts and associated hardware are ideal for the monitoring of cabin atmospheres containing potentially dangerous volatile compounds.
A framework for the comparative study of language.
Uriagereka, Juan; Reggia, James A; Wilkinson, Gerald S
2013-07-18
Comparative studies of language are difficult because few language precursors are recognized. In this paper we propose a framework for designing experiments that test for structural and semantic patterns indicative of simple or complex grammars as originally described by Chomsky. We argue that a key issue is whether animals can recognize full recursion, which is the hallmark of context-free grammar. We discuss limitations of recent experiments that have attempted to address this issue, and point out that experiments aimed at detecting patterns that follow a Fibonacci series have advantages over other artificial context-free grammars. We also argue that experiments using complex sequences of behaviors could, in principle, provide evidence for fully recursive thought. Some of these ideas could also be approached using artificial life simulations, which have the potential to reveal the types of evolutionary transitions that could occur over time. Because the framework we propose has specific memory and computational requirements, future experiments could target candidate genes with the goal of revealing the genetic underpinnings of complex cognition.
Ali, Abdulbaset; Hu, Bing; Ramahi, Omar
2015-05-15
This work presents a real life experiment of implementing an artificial intelligence model for detecting sub-millimeter cracks in metallic surfaces on a dataset obtained from a waveguide sensor loaded with metamaterial elements. Crack detection using microwave sensors is typically based on human observation of change in the sensor's signal (pattern) depicted on a high-resolution screen of the test equipment. However, as demonstrated in this work, implementing artificial intelligence to classify cracked from non-cracked surfaces has appreciable impact in terms of sensing sensitivity, cost, and automation. Furthermore, applying artificial intelligence for post-processing data collected from microwave sensors is a cornerstone for handheld test equipment that can outperform rack equipment with large screens and sophisticated plotting features. The proposed method was tested on a metallic plate with different cracks and the obtained experimental results showed good crack classification accuracy rates.
Tissue phantom-based breast cancer detection using continuous near-infrared sensor
Liu, Dan; Liu, Xin; Zhang, Yan; Wang, Qisong; Lu, Jingyang
2016-01-01
ABSTRACT Women's health is seriously threatened by breast cancer. Taking advantage of efficient diagnostic instruments to identify the disease is very meaningful in prolonging life. As a cheap noninvasive radiation-free technology, Near-infrared Spectroscopy is suitable for general breast cancer examination. A discrimination method of breast cancer is presented using the deference between absorption coefficients and applied to construct a blood oxygen detection device based on Modified Lambert-Beer theory. Combined with multi-wavelength multi-path near-infrared sensing technology, the proposed method can quantitatively distinguish the normal breast from the abnormal one by measuring the absorption coefficients of breast tissue and the blood oxygen saturation. An objective judgment about the breast tumor is made according to its high absorption of near-infrared light. The phantom experiment is implemented to show the presented method is able to recognize the absorption differences between phantoms and demonstrates its feasibility in the breast tumor detection. PMID:27459672
Tissue phantom-based breast cancer detection using continuous near-infrared sensor.
Liu, Dan; Liu, Xin; Zhang, Yan; Wang, Qisong; Lu, Jingyang
2016-09-02
Women's health is seriously threatened by breast cancer. Taking advantage of efficient diagnostic instruments to identify the disease is very meaningful in prolonging life. As a cheap noninvasive radiation-free technology, Near-infrared Spectroscopy is suitable for general breast cancer examination. A discrimination method of breast cancer is presented using the deference between absorption coefficients and applied to construct a blood oxygen detection device based on Modified Lambert-Beer theory. Combined with multi-wavelength multi-path near-infrared sensing technology, the proposed method can quantitatively distinguish the normal breast from the abnormal one by measuring the absorption coefficients of breast tissue and the blood oxygen saturation. An objective judgment about the breast tumor is made according to its high absorption of near-infrared light. The phantom experiment is implemented to show the presented method is able to recognize the absorption differences between phantoms and demonstrates its feasibility in the breast tumor detection.
Detecting double compression of audio signal
NASA Astrophysics Data System (ADS)
Yang, Rui; Shi, Yun Q.; Huang, Jiwu
2010-01-01
MP3 is the most popular audio format nowadays in our daily life, for example music downloaded from the Internet and file saved in the digital recorder are often in MP3 format. However, low bitrate MP3s are often transcoded to high bitrate since high bitrate ones are of high commercial value. Also audio recording in digital recorder can be doctored easily by pervasive audio editing software. This paper presents two methods for the detection of double MP3 compression. The methods are essential for finding out fake-quality MP3 and audio forensics. The proposed methods use support vector machine classifiers with feature vectors formed by the distributions of the first digits of the quantized MDCT (modified discrete cosine transform) coefficients. Extensive experiments demonstrate the effectiveness of the proposed methods. To the best of our knowledge, this piece of work is the first one to detect double compression of audio signal.
Make Caffeine Visible: a Fluorescent Caffeine “Traffic Light” Detector
NASA Astrophysics Data System (ADS)
Xu, Wang; Kim, Tae-Hyeong; Zhai, Duanting; Er, Jun Cheng; Zhang, Liyun; Kale, Anup Atul; Agrawalla, Bikram Keshari; Cho, Yoon-Kyoung; Chang, Young-Tae
2013-07-01
Caffeine has attracted abundant attention due to its extensive existence in beverages and medicines. However, to detect it sensitively and conveniently remains a challenge, especially in resource-limited regions. Here we report a novel aqueous phase fluorescent caffeine sensor named Caffeine Orange which exhibits 250-fold fluorescence enhancement upon caffeine activation and high selectivity. Nuclear magnetic resonance spectroscopy and Fourier transform infrared spectroscopy indicate that π-stacking and hydrogen-bonding contribute to their interactions while dynamic light scattering and transmission electron microscopy experiments demonstrate the change of Caffeine Orange ambient environment induces its fluorescence emission. To utilize this probe in real life, we developed a non-toxic caffeine detection kit and tested it for caffeine quantification in various beverages. Naked-eye sensing of various caffeine concentrations was possible based on color changes upon irradiation with a laser pointer. Lastly, we performed the whole system on a microfluidic device to make caffeine detection quick, sensitive and automated.
Ali, Abdulbaset; Hu, Bing; Ramahi, Omar M.
2015-01-01
This work presents a real-life experiment implementing an artificial intelligence model for detecting sub-millimeter cracks in metallic surfaces on a dataset obtained from a waveguide sensor loaded with metamaterial elements. Crack detection using microwave sensors is typically based on human observation of change in the sensor's signal (pattern) depicted on a high-resolution screen of the test equipment. However, as demonstrated in this work, implementing artificial intelligence to classify cracked from non-cracked surfaces has appreciable impacts in terms of sensing sensitivity, cost, and automation. Furthermore, applying artificial intelligence for post-processing the data collected from microwave sensors is a cornerstone for handheld test equipment that can outperform rack equipment with large screens and sophisticated plotting features. The proposed method was tested on a metallic plate with different cracks, and the experimental results showed good crack classification accuracy rates. PMID:25988871
Planetary protection program for Mars 94/96 mission.
Rogovski, G; Bogomolov, V; Ivanov, M; Runavot, J; Debus, A; Victorov, A; Darbord, J C
1996-01-01
Mars surface in-situ exploration started in 1975 with the American VIKING mission. Two probes landed on the northern hemisphere and provided, for the first time, detailed information on the martian terrain, atmosphere and meteorology. The current goal is to undertake larger surface investigations and many projects are being planned by the major Space Agencies with this objective. Among these projects, the Mars 94/96 mission will make a major contributor toward generating significant information about the martian surface on a large scale. Since the beginning of the Solar System exploration, planets where life could exist have been subject to planetary protection requirements. Those requirements accord with the COSPAR Policy and have two main goals: the protection of the planetary environment from influence or contamination by terrestrial microorganisms, the protection of life science, and particularly of life detection experiments searching extra-terrestrial life, and not life carried by probes and spacecrafts. As the conditions for life and survival for terrestrial microorganisms in the Mars environment became known, COSPAR recommendations were updated. This paper will describe the decontamination requirements which will be applied for the MARS 94/96 mission, the techniques and the procedures which are and will be used to realize and control the decontamination of probes and spacecrafts.
Blake, Ruth E.; Alt, Jeffrey C.; Martini, Anna M.
2001-01-01
The distinctive relations between biological activity and isotopic effect recorded in biomarkers (e.g., carbon and sulfur isotope ratios) have allowed scientists to suggest that life originated on this planet nearly 3.8 billion years ago. The existence of life on other planets may be similarly identified by geochemical biomarkers, including the oxygen isotope ratio of phosphate (δ18Op) presented here. At low near-surface temperatures, the exchange of oxygen isotopes between phosphate and water requires enzymatic catalysis. Because enzymes are indicative of cellular activity, the demonstration of enzyme-catalyzed PO4–H2O exchange is indicative of the presence of life. Results of laboratory experiments are presented that clearly show that δ18OP values of inorganic phosphate can be used to detect enzymatic activity and microbial metabolism of phosphate. Applications of δ18Op as a biomarker are presented for two Earth environments relevant to the search for extraterrestrial life: a shallow groundwater reservoir and a marine hydrothermal vent system. With the development of in situ analytical techniques and future planned sample return strategies, δ18Op may provide an important biosignature of the presence of life in extraterrestrial systems such as that on Mars. PMID:11226207
Blake, R E; Alt, J C; Martini, A M
2001-02-27
The distinctive relations between biological activity and isotopic effect recorded in biomarkers (e.g., carbon and sulfur isotope ratios) have allowed scientists to suggest that life originated on this planet nearly 3.8 billion years ago. The existence of life on other planets may be similarly identified by geochemical biomarkers, including the oxygen isotope ratio of phosphate (delta(18)O(p)) presented here. At low near-surface temperatures, the exchange of oxygen isotopes between phosphate and water requires enzymatic catalysis. Because enzymes are indicative of cellular activity, the demonstration of enzyme-catalyzed PO(4)-H(2)O exchange is indicative of the presence of life. Results of laboratory experiments are presented that clearly show that delta(18)O(P) values of inorganic phosphate can be used to detect enzymatic activity and microbial metabolism of phosphate. Applications of delta(18)O(p) as a biomarker are presented for two Earth environments relevant to the search for extraterrestrial life: a shallow groundwater reservoir and a marine hydrothermal vent system. With the development of in situ analytical techniques and future planned sample return strategies, delta(18)O(p) may provide an important biosignature of the presence of life in extraterrestrial systems such as that on Mars.
Bos, Fionneke M; Schoevers, Robert A; aan het Rot, Marije
2015-11-01
Experience sampling methods (ESM) and ecological momentary assessment (EMA) offer insight into daily life experiences, including symptoms of mental disorders. The application of ESM/EMA in psychopharmacology can be a valuable addition to more traditional measures such as retrospective self-report questionnaires because they may help reveal the impact of psychotropic medication on patients' actual experiences. In this paper we systematically review the existing literature on the use of ESM/EMA in psychopharmacology research. To this end, we searched the PsycInfo and Medline databases for all available ESM/EMA studies on the use of psychotropic medication in patients with DSM-III-R and DSM-IV disorders. Dissertations were excluded. We included 18 studies that applied ESM/EMA to study the effects of medication on patients with major depressive disorder, substance use disorder, attention-deficit hyperactivity disorder, psychotic disorder, and anxiety disorder. We found that ESM/EMA may allow researchers and clinicians to track patients during different phases of treatment: before treatment to predict outcome, during treatment to examine the effects of treatment on symptoms and different aspects of daily life experience, and after treatment to detect vulnerability for relapse. Moreover, ESM/EMA can potentially help determine how long and in what contexts medications are effective. Thus, ESM/EMA may benefit both researchers and clinicians and might prove to be an effective tool for improving the treatment of psychiatric patients. Copyright © 2015 Elsevier B.V. and ECNP. All rights reserved.
Searching for life in the Universe: unconventional methods for an unconventional problem.
Nealson, K H; Tsapin, A; Storrie-Lombardi, M
2002-12-01
The search for life, on and off our planet, can be done by conventional methods with which we are all familiar. These methods are sensitive and specific, and are often capable of detecting even single cells. However, if the search broadens to include life that may be different (even subtly different) in composition, the methods and even the approach must be altered. Here we discuss the development of what we call non-earthcentric life detection--detecting life with methods that could detect life no matter what its form or composition. To develop these methods, we simply ask, can we define life in terms of its general properties and particularly those that can be measured and quantified? Taking such an approach we can search for life using physics and chemistry to ask questions about structure, chemical composition, thermodynamics, and kinetics. Structural complexity can be searched for using computer algorithms that recognize complex structures. Once identified, these structures can be examined for a variety of chemical traits, including elemental composition, chirality, and complex chemistry. A second approach involves defining our environment in terms of energy sources (i.e., reductants), and oxidants (e.g. what is available to eat and breathe), and then looking for areas in which such phenomena are inexplicably out of chemical equilibrium. These disequilibria, when found, can then be examined in detail for the presence of the structural and chemical complexity that presumably characterizes any living systems. By this approach, we move the search for life to one that should facilitate the detection of any earthly life it encountered, as well as any non-conventional life forms that have structure, complex chemistry, and live via some form of redox chemistry.
Online model-based diagnosis to support autonomous operation of an advanced life support system.
Biswas, Gautam; Manders, Eric-Jan; Ramirez, John; Mahadevan, Nagabhusan; Abdelwahed, Sherif
2004-01-01
This article describes methods for online model-based diagnosis of subsystems of the advanced life support system (ALS). The diagnosis methodology is tailored to detect, isolate, and identify faults in components of the system quickly so that fault-adaptive control techniques can be applied to maintain system operation without interruption. We describe the components of our hybrid modeling scheme and the diagnosis methodology, and then demonstrate the effectiveness of this methodology by building a detailed model of the reverse osmosis (RO) system of the water recovery system (WRS) of the ALS. This model is validated with real data collected from an experimental testbed at NASA JSC. A number of diagnosis experiments run on simulated faulty data are presented and the results are discussed.
Online model-based diagnosis to support autonomous operation of an advanced life support system
NASA Technical Reports Server (NTRS)
Biswas, Gautam; Manders, Eric-Jan; Ramirez, John; Mahadevan, Nagabhusan; Abdelwahed, Sherif
2004-01-01
This article describes methods for online model-based diagnosis of subsystems of the advanced life support system (ALS). The diagnosis methodology is tailored to detect, isolate, and identify faults in components of the system quickly so that fault-adaptive control techniques can be applied to maintain system operation without interruption. We describe the components of our hybrid modeling scheme and the diagnosis methodology, and then demonstrate the effectiveness of this methodology by building a detailed model of the reverse osmosis (RO) system of the water recovery system (WRS) of the ALS. This model is validated with real data collected from an experimental testbed at NASA JSC. A number of diagnosis experiments run on simulated faulty data are presented and the results are discussed.
SNC Meteorites, Organic Matter and a New Look at Viking
NASA Technical Reports Server (NTRS)
Warmflash, David M.; Clemett, Simon J.; McKay, David S.
2001-01-01
Recently, evidence has begun to grow supporting the possibility that the Viking GC-MS would not have detected certain carboxylate salts that could have been present as metastable oxidation products of high molecular weight organic species. Additionally, despite the instrument's high sensitivity, the possibility had remained that very low levels of organic matter, below the instrument's detection limit, could have been present. In fact, a recent study indicates that the degradation products of several million microorganisms per gram of soil on Mars would not have been detected by the Viking GC-MS. Since the strength of the GC-MS findings was considered enough to dismiss the biology packet, particularly the LR results, any subsequent evidence suggesting that organic molecules may in fact be present on the Martian surface necessitates a re-evaluation of the Viking LR data. In addition to an advanced mass spectrometer to look for isotopic signatures of biogenic processes, future lander missions will include the ability to detect methane produced by methanogenic bacteria, as well as techniques based on biotechnology. Meanwhile, the identification of Mars samples already present on Earth in the form of the SNC meteorites has provided us with the ability to study samples of the Martian upper crust a decade or more in advance of any planned sample return missions. While contamination issues are of serious concern, the presence of indigenous organic matter in the form of polycyclic aromatic hydrocarbons has been detected in the Martian meteorites ALH84001 and Nakhla, while there is circumstantial evidence for carbonaceous material in Chassigny. The radiochronological ages of these meteorites are 4.5 Ga, 1.3 Ga, and 165 Ma respectively representing a span of time in Earth history from the earliest single-celled organisms to the present day. Given this perspective on organic material, a biological interpretation to the Viking LR results can no longer be ruled out. In the LR experiment, a solution containing C-14 labeled organic compounds was injected into soil samples. The detection of radioactivity in the overhead space would indicate that one or more of the substrates had been chemically converted into a carbon-containing gas. To serve as a control, some samples were heated enough to destroy most known terrestrial microbes so that an indication for life would be a positive response from unheated samples and a negative response from heated samples. On Mars, the LR results had met minimum criteria for a biological interpretation but due to the GC-MS results, the LR responses were later attributed to putative soil inorganic oxidants. Since the time of Viking, studies have been carried out with the objective of determining an oxidant or combination of oxidants that might exist on Mars and have produced the observed kinetics of the LR response. To date, no such agent has been found that produces all aspects of the LR results on Mars. While the above considerations in no way imply the existence of life forms at the two Viking landing sites, inorganic and biological explanations for the Viking LR data should now be considered equally plausible until more complete studies of the Martian surface are carried out. Therefore, in light of the SNC meteorites data and their implications for the possibility of organic matter near or on the Martian surface the Viking biology experiments should thus be seen, not as failures for their inability to provide unambiguous evidence for or against Martian life, but as a foundation for the development of future life-detection instruments. Additional information is contained in the original extended abstract.
Kuhrik, Marilee; Seckman, Christy; Kuhrik, Nancy; Ahearn, Tina; Ercole, Patrick
2011-12-01
Skin cancer is the most common cancer in the United States, with about 1,000,000 people developing the disease each year. The incidence of melanoma has rapidly increased in young white women between the ages of 15-34 over the last three decades. While melanoma accounts for approximately 3% of skin cancers, it causes more than 75% of skin cancer deaths. Thorough skin assessments and awareness of new or changing appearance of skin lesions are critical to early detection and treatment of skin cancer, as well as teaching sun-protective behaviors. Educators created a novel approach to "bring to life" skin cancer assessment skills to promote awareness of prevention and early detection of skin cancer using moulage in a human patient simulation lab. Through the use of moulage-like lesions, simulated patients were evaluated and taught skin cancer prevention and early detection principles by baccalaureate nursing students. The average age of study participants (n = 104) was 26.50 years. The majority of responders were female. At the end of the lab, students' average responses to an evaluation based on program goals were very positive. Anecdotal comments affirmed positive student perceptions of their simulation experience. Data analyses indicated item means were consistently higher for upper-division students. The age and gender of students who participated in this study align with the NCI statistics on age and gender of the population with increased incidence of melanoma.
Song, Shiming; Wei, Jie; Chen, Zhaojie; Lei, Yuhao; Zhang, Yan; Deng, Cheng; Tan, Huihua; Li, Xuesheng
2018-03-04
A sensitive and specific method for the determination of propineb and its metabolites, propylenethiourea (PTU) and propylenediamine (PDA), using gas chromatography with flame photometric detection (GC-FPD) and LC-MS/MS was developed and validated. Propineb and its metabolite residue dynamics in supervised field trials under Good Agricultural Practice (GAP) conditions in banana and soil were studied. Recovery of propineb (as CS 2 ), PDA and PTU ranged from 75.3 to 115.4% with RSD (n = 5) of 1.3-11.1%. The limit of quantification (LOQ) of CS 2 , PDA and PTU ranged from 0.005 to 0.01 mg kg -1 , and the limit of detection (LOD) ranged from 0.0015 to 0.0033 mg kg -1 . Dissipation experiments showed that the half-life of propineb in banana and soil ranged from 4.4 to 13.3 days. PTU was found in banana with a half-life of 31.5-69.3 days, while levels of PDA were less than 0.01 mg kg -1 in banana and soil. It has been suggested that PTU is the major metabolite of propineb in banana. The method was demonstrated to be reliable and sensitive for the routine monitoring of propineb and its metabolites in banana and soil. It also serves as a reference for the detection and monitoring of dithiocarbamates (DTCs) residues and the evaluation of their metabolic pathway.
Aubry, Lise M; Cam, Emmanuelle; Koons, David N; Monnat, Jean-Yves; Pavard, Samuel
2011-03-01
1. We assessed the relative influence of variability in recruitment age, dynamic reproductive investment (time-specific reproductive states) and frailty (unobserved differences in survival abilities across individuals) on survival in the black-legged kittiwake. Furthermore, we examined whether observed variability in survival trajectories was best explained by immediate reproductive investment, cumulative investment, or both. 2. Individuals that delayed recruitment (≥ age 7) suffered a higher mortality risk than early recruits (age 3), especially later in life, suggesting that recruitment age may be an indicator of individual quality. Although recruitment age helped explain variation in survival, time-varying reproductive investment had a more substantial influence. 3. The dichotomy of attempting to breed or not explained variability in survival across life better than other parameterizations of reproductive states such as clutch size, brood size or breeding success. In the kittiwake, the sinequanon condition to initiate reproduction is to hold a nest site, which is considered a very competitive activity. This might explain why attempting to breed is the key level of investment that affects survival, independent of the outcome (failure or success). 4. Interestingly, the more individuals cumulate reproductive attempts over life, the lower their mortality risk, indicating that breeding experience may be a good indicator of parental quality as well. In contrast, attempting to breed at time t increased the risk of mortality between t and t + 1. We thus detected an immediate trade-off between attempting to breed and survival in this population; however, the earlier individuals recruited, and the more breeding experience they accumulated, the smaller the cost. 5. Lastly, unobserved heterogeneity across individuals improved model fit more (1·3 times) than fixed and dynamic sources of observed heterogeneity in reproductive investment, demonstrating that it is critical to account for both sources of individual heterogeneity when studying survival trajectories. Only after simultaneously accounting for both sources of heterogeneity were we able to detect the 'cost' of immediate reproductive investment on survival and the 'benefit' of cumulative breeding attempts (experience), a proxy to individual quality. © 2010 The Authors. Journal of Animal Ecology © 2010 British Ecological Society.
Recurrent bottlenecks in the malaria life cycle obscure signals of positive selection.
Chang, Hsiao-Han; Hartl, Daniel L
2015-02-01
Detecting signals of selection in the genome of malaria parasites is a key to identify targets for drug and vaccine development. Malaria parasites have a unique life cycle alternating between vector and host organism with a population bottleneck at each transition. These recurrent bottlenecks could influence the patterns of genetic diversity and the power of existing population genetic tools to identify sites under positive selection. We therefore simulated the site-frequency spectrum of a beneficial mutant allele through time under the malaria life cycle. We investigated the power of current population genetic methods to detect positive selection based on the site-frequency spectrum as well as temporal changes in allele frequency. We found that a within-host selective advantage is difficult to detect using these methods. Although a between-host transmission advantage could be detected, the power is decreased when compared with the classical Wright-Fisher (WF) population model. Using an adjusted null site-frequency spectrum that takes the malaria life cycle into account, the power of tests based on the site-frequency spectrum to detect positive selection is greatly improved. Our study demonstrates the importance of considering the life cycle in genetic analysis, especially in parasites with complex life cycles.
Progress in Life Marker Chip Technology for Detection of Life on Mars
NASA Astrophysics Data System (ADS)
Sims, M. R.; Cullen, D. C.; Laan, E.; Borst, G.; Prak, A.; Richter, L.; Gaubert, F.; Steele, A.; Parnell, J.; Sephton, M.
2007-12-01
Detection of Life on Mars will rely on detection of biomarkers, physical or chemical structures that can be associated with Life. As a possible payload for the ESA ExoMars rover mission planned in 2013 and other future missions a Life Marker Chip instrument is being developed. This instrument uses immuno-assay techniques to detect the relevant biomarkers. This paper describes the typical targets it will search for, its operating principle and the status of development. 63 biomarker targets have been identified and assays have been developed for a limited subset. Assay development includes use of recombinant DNA techniques to generate the molecular receptors (antibodies). This type of instrument has applications in terrestrial research e.g. sub-glacial lakes as well as planetary exploration. Breadboard demonstrators have been built of the assay system and key components of the micro-fluidics. Results from these breadboards will be presented, along with plans for future development.
Raman Life Detection Instrument Development for Icy Worlds
NASA Technical Reports Server (NTRS)
Thomson, Seamus; Allen, A'Lester; Gutierrez, Daniel; Quinn, Richard C.; Chen, Bin; Koehne, Jessica E.
2017-01-01
The objective of this project is to develop a compact, high sensitivity Raman sensor for detection of life signatures in a flow cell configuration to enable bio-exploration and life detection during future mission to our Solar Systems Icy Worlds. The specific project objectives are the following: 1) Develop a Raman spectroscopy liquid analysis sensor for biosignatures; 2) Demonstrate applicability towards a future Enceladus or other Icy Worlds missions; 3) Establish key parameters for integration with the ARC Sample Processor for Life on Icy Worlds (SPLIce); 4) Position ARC for a successful response to upcoming Enceladus or other Icy World mission instrument opportunities.
NASA Astrophysics Data System (ADS)
Batory, Krzysztof J.; Govindjee; Andersen, Dale; Presley, John; Lucas, John M.; Sears, S. Kelly; Vali, Hojatollah
Unambiguous detection of extraterrestrial nitrogenous hydrocarbon microbiology requires an instrument both to recognize potential biogenic specimens and to successfully discriminate them from geochemical settings. Such detection should ideally be in-situ and not jeopardize other experiments by altering samples. Taken individually most biomarkers are inconclusive. For example, since amino acids can be synthesized abiotically they are not always considered reliable biomarkers. An enantiomeric imbalance, which is characteristic of all terrestrial life, may be questioned because chirality can also be altered abiotically. However, current scientific understanding holds that aggregates of identical proteins or proteinaceous complexes, with their well-defined amino acid residue sequences, are indisputable biomarkers. Our paper describes the Mars Analytical Microimager, an instrument for the simultaneous imaging of generic autofluorescent biomarkers and overall morphology. Autofluorescence from ultraviolet to near-infrared is emitted by all known terrestrial biology, and often as consistent complex bands uncharacteristic of abiotic mineral luminescence. The MAM acquires morphology, and even sub-micron morphogenesis, at a 3-centimeter working distance with resolution approaching a laser scanning microscope. Luminescence is simultaneously collected via a 2.5-micron aperture, thereby permitting accurate correlation of multi-dimensional optical behavior with specimen morphology. A variable wavelength excitation source and photospectrometer serve to obtain steady-state and excitation spectra of biotic and luminescent abiotic sources. We believe this is the first time instrumentation for detecting hydrated or desiccated microbiology non-destructively in-situ has been demonstrated. We have obtained excellent preliminary detection of biota and inorganic matrix discrimination from terrestrial polar analogues, and perimetric morphology of individual magnetotactic bacteria. Proposed analytical components for enhanced detection are: fluorescence anisotropy which analyzes chromophore-based proteins, anisotropy depletion to detect the presence of a fluid environment, anisotropy excitation spectrum for augmented characterization, and fluorescence-detected circular dichroism. Because all its analytical components are independent of chirality and amino acid types, life detection ability of the MAM is not limited to the terrestrial core biomolecular subsets.
Work-Life Balance and Ideal Worker Expectations for Administrators
ERIC Educational Resources Information Center
Wilk, Kelly E.
2016-01-01
This chapter explores the work-life experiences of administrators as well as whether and how the ideal worker model affects those experiences. Departmental and supervisory differences and technology complicate administrators' work-life experiences.
NASA Astrophysics Data System (ADS)
Levin, E.; Zarnowski, A.; McCarty, J. L.; Bialas, J.; Banaszek, A.; Banaszek, S.
2016-06-01
Significant efforts are invested by rescue agencies worldwide to save human lives during natural and man-made emergency situations including those that happen in wilderness locations. These emergency situations include but not limited to: accidents with alpinists, mountainous skiers, people hiking and lost in remote areas. Sometimes in a rescue operation hundreds of first responders are involved to save a single human life. There are two critical issues where geospatial imaging can be a very useful asset in rescue operations support: 1) human detection and 2) confirming a fact that detected a human being is alive. International group of researchers from the Unites States and Poland collaborated on a pilot research project devoted to identify a feasibility of use for the human detection and alive-human state confirmation small unmanned aerial vehicles (SUAVs) and inexpensive forward looking infrared (FLIR) sensors. Equipment price for both research teams was below 8,000 including 3DR quadrotor UAV and Lepton longwave infrared (LWIR) imager which costs around 250 (for the US team); DJI Inspire 1 UAS with commercial Tamarisc-320 thermal camera (for the Polish team). Specifically both collaborating groups performed independent experiments in the USA and Poland and shared imaging data of on the ground and airborne electro-optical and FLIR sensor imaging collected. In these experiments dead bodies were emulated by use of medical training dummies. Real humans were placed nearby as live human subjects. Electro-optical imagery was used for the research in optimal human detection algorithms. Furthermore, given the fact that a dead human body after several hours has a temperature of the surrounding environment our experiments were challenged by the SUAS data optimization, i.e., distance from SUAV to object so that the FLIR sensor is still capable to distinguish temperature differences between a dummy and a real human. Our experiments indicated feasibility of use SUAVs and small thermal sensors for the human detection scenarios described above. Differences in temperatures were collected by deployed imaging acquisition platform are interpretable on FLIR images visually. Moreover, we applied ENVI image processing functions for calibration and numerical estimations of such a temperature differences. There are more potential system functionalities such as voice messages from rescue teams and even distant medication delivery for the victims of described emergencies. This paper describes experiments, processing results, and future research in more details.
NASA Astrophysics Data System (ADS)
Safonova, M.; Murthy, J.; Shchekinov, Yu. A.
2016-04-01
A `habitable zone' of a star is defined as a range of orbits within which a rocky planet can support liquid water on its surface. The most intriguing question driving the search for habitable planets is whether they host life. But is the age of the planet important for its habitability? If we define habitability as the ability of a planet to beget life, then probably it is not. After all, life on Earth has developed within only ~800 Myr after its formation - the carbon isotope change detected in the oldest rocks indicates the existence of already active life at least 3.8 Gyr ago. If, however, we define habitability as our ability to detect life on the surface of exoplanets, then age becomes a crucial parameter. Only after life had evolved sufficiently complex to change its environment on a planetary scale, can we detect it remotely through its imprint on the atmosphere - the so-called biosignatures, out of which the photosynthetic oxygen is the most prominent indicator of developed (complex) life as we know it. Thus, photosynthesis is a powerful biogenic engine that is known to have changed our planet's global atmospheric properties. The importance of planetary age for the detectability of life as we know it follows from the fact that this primary process, photosynthesis, is endothermic with an activation energy higher than temperatures in habitable zones, and is sensitive to the particular thermal conditions of the planet. Therefore, the onset of photosynthesis on planets in habitable zones may take much longer time than the planetary age. The knowledge of the age of a planet is necessary for developing a strategy to search for exoplanets carrying complex (developed) life - many confirmed potentially habitable planets are too young (orbiting Population I stars) and may not have had enough time to develop and/or sustain detectable life. In the last decade, many planets orbiting old (9-13 Gyr) metal-poor Population II stars have been discovered. Such planets had had enough time to develop necessary chains of chemical reactions and may carry detectable life if located in a habitable zone. These old planets should be primary targets in search for the extraterrestrial life.
Gastrointestinal symptoms and quality of life in screen-detected celiac disease.
Paavola, Aku; Kurppa, Kalle; Ukkola, Anniina; Collin, Pekka; Lähdeaho, Marja-Leena; Huhtala, Heini; Mäki, Markku; Kaukinen, Katri
2012-10-01
Active serological screening has proved an effective means of increasing the diagnostic rate in celiac disease. The effects of a long-term gluten-free diet on possible gastrointestinal symptoms and psychological well-being in screen-detected patients have nevertheless remained obscure. Abdominal symptoms and quality of life were measured in a large cohort of treated screen-detected celiac adults. Comparisons were made with corresponding symptom-detected patients and with non-celiac controls. Dietary adherence was assessed both by structured interview and by serological testing. In both screen- and symptom-detected celiac groups, 88% of the patients were adherent. On a diet, both screen- and symptom-detected patients reported significantly more gastrointestinal symptoms than non-celiac controls. Those screen-detected patients who reported having no symptoms at the time of diagnosis, also remained asymptomatic during the diet. Despite persistent symptoms, psychological well-being in screen-detected patients was comparable with that in non-celiac controls, whereas the symptom-detected patients showed lower quality of life. Long-term treated screen-detected celiac patients, especially women, suffer from gastrointestinal symptoms on a gluten free diet similarly to symptom-detected patients. However, despite a similar frequency of persistent symptoms, the quality of life was unimpaired in the screen found, but remained low in the symptom-detected group. Copyright © 2012 Editrice Gastroenterologica Italiana S.r.l. Published by Elsevier Ltd. All rights reserved.
Selbmann, Laura; Pacelli, Claudia; Zucconi, Laura; Dadachova, Ekaterina; Moeller, Ralf; de Vera, Jean-Pierre; Onofri, Silvano
2018-06-01
The Antarctic black meristematic fungus Cryomyces antarcticus CCFEE 515 occurs endolithically in the McMurdo Dry Valleys of Antarctica, one of the best analogue for Mars environment on Earth. To date, this fungus is considered one of the best eukaryotic models for astrobiological studies and has been repeatedly selected for space experiments in the last decade. The obtained results are reviewed here, with special focus on responses to space relevant irradiation, UV radiation, and both sparsely and densely ionizing radiation, which represent the major injuries for a putative space-traveller. The remarkable resistance of this model organism to space stress, its radioresistance in particular, and mechanisms involved, significantly contributed to expanding our concept of limits for life and provided new insights on the origin and evolution of life in planetary systems, habitability, and biosignatures for life detection as well as on human protection during space missions. Copyright © 2017 British Mycological Society. Published by Elsevier Ltd. All rights reserved.
Characterization of an Electroanalytical Instrument Suite Searching for Water and Life on Mars
NASA Technical Reports Server (NTRS)
Bostic, Heidi E.
2005-01-01
Seeking the existence of life on other planets is an essential part of NASA's research. Our terrestrial experience suggests that water is a mandatory resource for life to exist and thrive. However, instruments capable of detecting water at the levels likely to be present on Mars are lacking. This project tests the possibility of using electrical measurements of soils, at variable frequencies, as a water detector. Generally, the electrical resistance of soils can be described as a combination of resistance and capacitance, which can be described by a vector including a magnitude and (phase) angle. By specifically studying the impedance measurements and phase angles of different types of soil, spiked with varying concentrations of dissolved ions, measurements can be taken to provide an idea of the behavior of dry Martian soils. The presentation will describe the experimental technique, apparatus and procedures, as well as results conducted to calibrate the instrument and to establish sample preparation protocols.
The Impact of the Temporal Distribution of Communicating Civilizations on Their Detectability.
Balbi, Amedeo
2018-01-01
We used a statistical model to investigate the detectability (defined by the requirement that causal contact has been initiated with us) of communicating civilizations within a volume of the Universe surrounding our location. If the civilizations are located in our galaxy, the detectability requirement imposes a strict constraint on their epoch of appearance and their communicating life span. This, in turn, implies that our ability to gather empirical evidence of the fraction of civilizations within range of detection strongly depends on the specific features of their temporal distribution. Our approach illuminates aspects of the problem that can escape the standard treatment based on the Drake equation. Therefore, it might provide the appropriate framework for future studies dealing with the evolutionary aspects of the search for extraterrestrial intelligence (SETI). Key Words: Astrobiology-Extraterrestrial life-SETI-Complex life-Life detection-Intelligence. Astrobiology 18, 54-58.
Ahrens, Kym R.; Spencer, Renee; Bonnar, Mavis; Coatney, Alexis; Hall, Tyson
2016-01-01
Purpose To explore how attitudes, norms, behaviors, responses to early life experiences, and protective factors influence pregnancy and sexually transmitted infection risks from the perspectives of current and former foster youth to inform the development of prevention strategies. Methods We conducted semi-structured individual qualitative interviews with a diverse sample of 22 current/former foster youth aged 15–21 years (63% female; average age = 18.6 years). We then used Theoretical Thematic Analysis to systematically analyze the data for key themes related to sexual health in four categories: 1) norms and attitudes, 2) responses to early life experiences, 3) protective factors, and 4) youth-driven intervention ideas. Results Participants reported a range of sexual experience levels, varied sexual orientations, and also reported varied life experiences prior to and during foster care. We detected several norms and attitudes that likely contribute to risks of early pregnancies and sexually transmitted infections. These included that one can tell by looking whether a partner is trustworthy or has a sexually transmitted infection, that condoms aren’t necessary with long-term or infrequent partners or if birth control is used, and that teen pregnancy is an inevitable event. With respect to responses to early life experiences, youth frequently described difficulties dealing with strong emotions in the context of romantic and/or sexual relationships; many attributed these difficulties to early experiences with biological family members or in foster care. Participants linked emotion regulation difficulties with struggles in trust appraisal, effective communication, and impulsive behaviors. Youth also described a variety of protective factors that they felt helped them prevent sexual risk behaviors or improved their lives in other respects. Finally, participants endorsed factors likely to improve intervention acceptability and efficacy, including an open, non-judgmental group-based environment, involvement of peer mentors, and inclusion of caregiver and caseworker training components. Conclusions Trauma-informed, tailored intervention strategies which address key norms and attitudes and provide broad-based assertiveness and emotion regulation skills are likely to be the most effective strategies to reduce risks of teen pregnancies and sexually transmitted infections among teens in foster care. Group-based interventions that involve peer mentors and caregiver and caseworker components may be especially acceptable and effective for teens in foster and/or kinship care. PMID:26941470
Brain structure correlates of urban upbringing, an environmental risk factor for schizophrenia.
Haddad, Leila; Schäfer, Axel; Streit, Fabian; Lederbogen, Florian; Grimm, Oliver; Wüst, Stefan; Deuschle, Michael; Kirsch, Peter; Tost, Heike; Meyer-Lindenberg, Andreas
2015-01-01
Urban upbringing has consistently been associated with schizophrenia, but which specific environmental exposures are reflected by this epidemiological observation and how they impact the developing brain to increase risk is largely unknown. On the basis of prior observations of abnormal functional brain processing of social stress in urban-born humans and preclinical evidence for enduring structural brain effects of early social stress, we investigated a possible morphological correlate of urban upbringing in human brain. In a sample of 110 healthy subjects studied with voxel-based morphometry, we detected a strong inverse correlation between early-life urbanicity and gray matter (GM) volume in the right dorsolateral prefrontal cortex (DLPFC, Brodmann area 9). Furthermore, we detected a negative correlation of early-life urbanicity and GM volumes in the perigenual anterior cingulate cortex (pACC) in men only. Previous work has linked volume reductions in the DLPFC to the exposure to psychosocial stress, including stressful experiences in early life. Besides, anatomical and functional alterations of this region have been identified in schizophrenic patients and high-risk populations. Previous data linking functional hyperactivation of pACC during social stress to urban upbringing suggest that the present interaction effect in brain structure might contribute to an increased risk for schizophrenia in males brought up in cities. Taken together, our results suggest a neural mechanism by which early-life urbanicity could impact brain architecture to increase the risk for schizophrenia. © The Author 2014. Published by Oxford University Press on behalf of the Maryland Psychiatric Research Center. All rights reserved. For permissions, please email: journals.permissions@oup.com.
NASA Technical Reports Server (NTRS)
Glavin, Daniel P.; Dworkin, Jason P.; Lupisella, Mark; Williams, David R.; Kminek, Gerhard; Rummel, John D.
2010-01-01
NASA and ESA have outlined visions for solar system exploration that will include a series of lunar robotic precursor missions to prepare for, and support a human return to the Moan, and future human exploration of Mars and other destinations, including possibly asteroids. One of the guiding principles for exploration is to pursue compelling scientific questions about the origin and evolution of life. The search for life on objects such as Mars will require careful operations, and that all systems be sufficiently cleaned and sterilized prior to launch to ensure that the scientific integrity of extraterrestrial samples is not jeopardized by terrestrial organic contamination. Under the Committee on Space Research's (COSPAR's) current planetary protection policy for the Moon, no sterilization procedures are required for outbound lunar spacecraft, nor is there a different planetary protection category for human missions, although preliminary C SPAR policy guidelines for human missions to Mars have been developed. Future in situ investigations of a variety of locations on the Moon by highly sensitive instruments designed to search for biologically derived organic compounds would help assess the contamination of the Moon by lunar spacecraft. These studies could also provide valuable "ground truth" data for Mars sample return missions and help define planetary protection requirements for future Mars bound spacecraft carrying life detection experiments. In addition, studies of the impact of terrestrial contamination of the lunar surface by the Apollo astronauts could provide valuable data to help refine future: Mars surface exploration plans for a human mission to Mars.
Climatic niche and flowering and fruiting phenology of an epiphytic plant
Barve, Narayani; Martin, Craig E.; Peterson, A. Townsend
2015-01-01
Species have geographic distributions constrained by combinations of abiotic factors, biotic factors and dispersal-related factors. Abiotic requirements vary across the life stages for a species; for plant species, a particularly important life stage is when the plant flowers and develops seeds. A previous year-long experiment showed that ambient temperature of 5–35 °C, relative humidity of >50 % and ≤15 consecutive rainless days are crucial abiotic conditions for Spanish moss (Tillandsia usneoides L.). Here, we explore whether these optimal physiological intervals relate to the timing of the flowering and fruiting periods of Spanish moss across its range. As Spanish moss has a broad geographic range, we examined herbarium specimens to detect and characterize flowering/fruiting periods for the species across the Americas; we used high-temporal-resolution climatic data to assess the availability of optimal conditions for Spanish moss populations during each population's flowering period. We explored how long populations experience suboptimal conditions and found that most populations experience suboptimal conditions in at least one environmental dimension. Flowering and fruiting periods of Spanish moss populations are either being optimized for one or a few parameters or may be adjusted such that all parameters are suboptimal. Spanish moss populations appear to be constrained most closely by minimum temperature during this period. PMID:26359490
NASA Technical Reports Server (NTRS)
Rummel, John D.
2001-01-01
Before martian soil and rock samples can be distributed to the research community, the returned materials will initially be quarantined and examined in a proposed BSL-4 containment facility to assure that no putative martian microorganisms or attendant potential biohazards exist. During the initial quarantine, state-of-the-art life detection and biohazard testing of the returned martian samples will be conducted. Life detection, as defined here in regard to Mars sample return missions, is the detection of living organisms and/or materials that have been derived from living organisms that may be present in the sample.
Baldewijns, Greet; Debard, Glen; Mertes, Gert; Vanrumste, Bart; Croonenborghs, Tom
2016-03-01
Fall incidents are an important health hazard for older adults. Automatic fall detection systems can reduce the consequences of a fall incident by assuring that timely aid is given. The development of these systems is therefore getting a lot of research attention. Real-life data which can help evaluate the results of this research is however sparse. Moreover, research groups that have this type of data are not at liberty to share it. Most research groups thus use simulated datasets. These simulation datasets, however, often do not incorporate the challenges the fall detection system will face when implemented in real-life. In this Letter, a more realistic simulation dataset is presented to fill this gap between real-life data and currently available datasets. It was recorded while re-enacting real-life falls recorded during previous studies. It incorporates the challenges faced by fall detection algorithms in real life. A fall detection algorithm from Debard et al. was evaluated on this dataset. This evaluation showed that the dataset possesses extra challenges compared with other publicly available datasets. In this Letter, the dataset is discussed as well as the results of this preliminary evaluation of the fall detection algorithm. The dataset can be downloaded from www.kuleuven.be/advise/datasets.
Mars, clays and the origins of life
NASA Technical Reports Server (NTRS)
Hartman, Hyman
1989-01-01
To detect life in the Martian soil, tests were designed to look for respiration and photosynthesis. Both tests (labeled release, LR, and pyrolytic release, PR) for life in the Martian soils were positive. However, when the measurement for organic molecules in the soil of Mars was made, none were found. The interpretation given is that the inorganic constituents of the soil of Mars were responsible for these observations. The inorganic analysis of the soil was best fitted by a mixture of minerals: 60 to 80 percent clay, iron oxide, quartz, and soluble salts such as halite (NaCl). The minerals most successful in simulating the PR and LR experiments are iron-rich clays. There is a theory that considers clays as the first organisms capable of replication, mutation, and catalysis, and hence of evolving. Clays are formed when liquid water causes the weathering of rocks. The distribution of ions such as aluminum, magnesium, and iron play the role of bases in the DNA. The information was stored in the distribution of ions in the octahedral and tetrahedral molecules, but that they could, like RNA and DNA, replicate. When the clays replicated, each sheet of clay would be a template for a new sheet. The ion substitutions in one clay sheet would give rise to a complementary or similar pattern on the clay synthesized on its surface. It was theorized that it was on the surface of replicating iron-rich clays that carbon dioxide would be fixed in the light into organic acids such as formic or oxalic acid. If Mars had liquid water during a warm period in its past, clay formation would have been abundant. These clays would have replicated and evolved until the liquid water was removed due to cooling of Mars. It is entirely possible that the Viking mission detected life on Mars, but it was clay life that awaits the return of water to continue its evolution into life based on organic molecules.
The sample handling system for the Mars Icebreaker Life mission: from dirt to data.
Davé, Arwen; Thompson, Sarah J; McKay, Christopher P; Stoker, Carol R; Zacny, Kris; Paulsen, Gale; Mellerowicz, Bolek; Glass, Brian J; Willson, David; Bonaccorsi, Rosalba; Rask, Jon
2013-04-01
The Mars Icebreaker Life mission will search for subsurface life on Mars. It consists of three payload elements: a drill to retrieve soil samples from approximately 1 m below the surface, a robotic sample handling system to deliver the sample from the drill to the instruments, and the instruments themselves. This paper will discuss the robotic sample handling system. Collecting samples from ice-rich soils on Mars in search of life presents two challenges: protection of that icy soil--considered a "special region" with respect to planetary protection--from contamination from Earth, and delivery of the icy, sticky soil to spacecraft instruments. We present a sampling device that meets these challenges. We built a prototype system and tested it at martian pressure, drilling into ice-cemented soil, collecting cuttings, and transferring them to the inlet port of the SOLID2 life-detection instrument. The tests successfully demonstrated that the Icebreaker drill, sample handling system, and life-detection instrument can collectively operate in these conditions and produce science data that can be delivered via telemetry--from dirt to data. Our results also demonstrate the feasibility of using an air gap to prevent forward contamination. We define a set of six analog soils for testing over a range of soil cohesion, from loose sand to basalt soil, with angles of repose of 27° and 39°, respectively. Particle size is a key determinant of jamming of mechanical parts by soil particles. Jamming occurs when the clearance between moving parts is equal in size to the most common particle size or equal to three of these particles together. Three particles acting together tend to form bridges and lead to clogging. Our experiments show that rotary-hammer action of the Icebreaker drill influences the particle size, typically reducing particle size by ≈ 100 μm.
Skarupski, Kimberly A; Parisi, Jeanine M; Thorpe, Roland; Tanner, Elizabeth; Gross, Deborah
2016-01-01
To explore the association of experiencing death, trauma, and abuse during childhood with depressive symptoms and quality of life at mid-life among incarcerated men and to understand how current social support and coping strategies mediate the impact of childhood trauma histories on mental health. Study participants were 192 male inmates in a maximum security prison. Participants completed measures of adverse childhood experiences related to death, trauma, and abuse, and depressive symptoms and quality of life. Data were analyzed using multiple mediation modeling. Men who reported having experienced adverse childhood experiences reported more depressive symptoms and lower quality of life than their counterparts. The results showed that in models both unadjusted and adjusted for age, race, education, number of years served, and whether the inmate had a life sentence, the association between adverse childhood experiences and quality of life were partially explained by the total of the indirect effects (point estimate = -.5052; CI.95 = -1.0364, -.0429 and point estimate = -.7792; CI.95 = -1.6369, -.0381), primarily via social support. However, the associations between adverse childhood experiences and depressive symptoms were not explained by social support and coping. Adverse childhood experiences are associated with deleterious mental health effects in later life. Social support and coping partially mediate the association between adverse childhood experiences and quality of life. The high prevalence of childhood trauma among aging prison inmates warrants attention to increasing social support mechanisms to improve mental health.
NASA Technical Reports Server (NTRS)
Hudson, C. M.
1972-01-01
Axial load fatigue life, fatigue-crack propagation, and fracture toughness tests were conducted on 0.090-inch thick specimens made of 7075-T6 aluminum alloy. The fatigue life and fatigue-crack propagation experiments were conducted at a stress ratio of 0.02. Maximum stresses ranged from 33 to 60 ksi in the fatigue life experiments, and from 10 to 40 ksi in the fatigue-crack propagation experiments, and fatigue life experiments were conducted at gas pressures of 760, 0.5, 0.05, and 0.00000005 torr. Fatigue-crack-growth and fracture toughness experiments were conducted at gas pressures of 760 and 5 x 10 to the minus 8th power torr. Residual stress measurements were made on selected fatigue life specimens to determine the effect of such stresses on fatigue life. Analysis of the results from the fatigue life experiments indicated that fatigue life progressively increased as the gas pressure decreased. Analysis of the results from the fatigue-crack-growth experiments indicates that at low values of stress-intensity range, the fatigue crack growth rates were approximately twice as high in air as in vacuum. Fracture toughness data showed there was essentially no difference in the fracture toughness of 7075-T6 in vacuum and in air.
Antibiotic Resistome: Improving Detection and Quantification Accuracy for Comparative Metagenomics.
Elbehery, Ali H A; Aziz, Ramy K; Siam, Rania
2016-04-01
The unprecedented rise of life-threatening antibiotic resistance (AR), combined with the unparalleled advances in DNA sequencing of genomes and metagenomes, has pushed the need for in silico detection of the resistance potential of clinical and environmental metagenomic samples through the quantification of AR genes (i.e., genes conferring antibiotic resistance). Therefore, determining an optimal methodology to quantitatively and accurately assess AR genes in a given environment is pivotal. Here, we optimized and improved existing AR detection methodologies from metagenomic datasets to properly consider AR-generating mutations in antibiotic target genes. Through comparative metagenomic analysis of previously published AR gene abundance in three publicly available metagenomes, we illustrate how mutation-generated resistance genes are either falsely assigned or neglected, which alters the detection and quantitation of the antibiotic resistome. In addition, we inspected factors influencing the outcome of AR gene quantification using metagenome simulation experiments, and identified that genome size, AR gene length, total number of metagenomics reads and selected sequencing platforms had pronounced effects on the level of detected AR. In conclusion, our proposed improvements in the current methodologies for accurate AR detection and resistome assessment show reliable results when tested on real and simulated metagenomic datasets.
NASA Astrophysics Data System (ADS)
Murray, A.
2014-04-01
Ice-entrained Lake Vida brine has provided an accessible natural habitat to study life in the slow lane - where cellular growth is limited, but not extinguished. We measured in situ stable isotopic signatures of N2O, SO42-, H2, conducted experiments utilizing stable isotope geochemical tracers to detect microbial transformations and employed radioisotopically-labeled amino acid precursors to detect cellular macromolecule biosynthesis. The results indicated a dominance of abiotic processes in the brine - yet support metabolically active life through detection of nominal rates of protein biosynthesis. At the same time, the brine has posed a challenge to our understanding of ecosystem energetics. Data collected thus far suggests that the brine is isolated from surfical processes and receives no new mass or energy from above. Calculations have estimated carbon remineralization rates, which indicate that resources should be depleted to the level of small molecules perhaps supporting a methanogenic ecosystem given the amount of time since encapsulation at the temperatures recorded - yet the brine is resource-rich harboring abundant bacteria and large molecules, in addition to a complex mixture of both reduced and oxidized compounds. This has motivated explorations into alternative sources of energy such as hydrogen - which was detected at levels 10 micromolar - that could be generated by brine-rock interactions and supply endogenous energy to this closed ecosystem. This cold, salty, anoxic and organically rich brine, provides insight into a new category of habitable earth ecosystems that may also give us food for thought when considering habitability of giant planet icy worlds or of icy exoplanets. However, the methods we use, and the framework of scientific inquiry applied, are limited by perception and familiarity of rates of change that are important in human time scales. The Vida-icy brine ecosystem provides a model for expansion of our understanding of habitability in which time scales need to be extended, and the role of intermingling abiotic and biotic processes need to be considered.
Life adverse experiences in relation with obesity and binge eating disorder: A systematic review
Palmisano, Giovanni Luca; Innamorati, Marco; Vanderlinden, Johan
2016-01-01
Background and aims Several studies report a positive association between adverse life experiences and adult obesity. Despite the high comorbidity between binge eating disorder (BED) and obesity, few authors have studied the link between trauma and BED. In this review the association between exposure to adverse life experiences and a risk for the development of obesity and BED in adulthood is explored. Methods Based on a scientific literature review in Medline, PubMed and PsycInfo databases, the results of 70 studies (N = 306,583 participants) were evaluated including 53 studies on relationship between adverse life experiences and obesity, 7 studies on post-traumatic stress disorder (PTSD) symptoms in relation to obesity, and 10 studies on the association between adverse life experiences and BED. In addition, mediating factors between the association of adverse life experiences, obesity and BED were examined. Results The majority of studies (87%) report that adverse life experiences are a risk factor for developing obesity and BED. More precisely a positive association between traumatic experiences and obesity and PTSD and obesity were found, respectively, in 85% and 86% of studies. Finally, the great majority of studies (90%) between trauma and the development of BED in adulthood strongly support this association. Meanwhile, different factors mediating between the trauma and obesity link were identified. Discussion and conclusions Although research data show a strong association between life adverse experiences and the development of obesity and BED, more research is needed to explain this association. PMID:28092189
NDE: A key to engine rotor life prediction
NASA Technical Reports Server (NTRS)
Doherty, J. E.
1977-01-01
A key ingredient in the establishment of safe life times for critical components is the means of reliably detecting flaws which may potentially exist. Currently used nondestructive evaluation procedures are successful in detecting life limiting defects; however, the development of automated and computer aided NDE technology permits even greater assurance of flight safety.
Sweep Width Determination for HU-25B Airborne Radars: Life Raft and Recreational Boat Targets
1989-09-01
in this case ), instead of to multiple parameters of interest. The effects of other parameters cannot be identified or quantified. 2 . The binary...rougher than those represented in the main body of data, averaging 9 to 10 feet (see section 1.3.6). Table 2 -1. Number of Searcher/Target Interactions...1987 experiment. 2 -1 2.2 DETECTION PERFORMANCE Sections 2.2.1 through 2.2.3 present results of the AN/APS-127 FLAR, AN/APS-131 SLAR, and combined FLAK
Focusing and directional beaming effects of airborne sound through a planar lens with zigzag slits
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tang, Kun; Qiu, Chunyin, E-mail: cyqiu@whu.edu.cn; Lu, Jiuyang
2015-01-14
Based on the Huygens-Fresnel principle, we design a planar lens to efficiently realize the interconversion between the point-like sound source and Gaussian beam in ambient air. The lens is constructed by a planar plate perforated elaborately with a nonuniform array of zigzag slits, where the slit exits act as subwavelength-sized secondary sources carrying desired sound responses. The experiments operated at audible regime agree well with the theoretical predictions. This compact device could be useful in daily life applications, such as for medical and detection purposes.
Operational plans for life science payloads - From experiment selection through postflight reporting
NASA Technical Reports Server (NTRS)
Mccollum, G. W.; Nelson, W. G.; Wells, G. W.
1976-01-01
Key features of operational plans developed in a study of the Space Shuttle era life science payloads program are presented. The data describes the overall acquisition, staging, and integration of payload elements, as well as program implementation methods and mission support requirements. Five configurations were selected as representative payloads: (a) carry-on laboratories - medical emphasis experiments, (b) mini-laboratories - medical/biology experiments, (c) seven-day dedicated laboratories - medical/biology experiments, (d) 30-day dedicated laboratories - Regenerative Life Support Evaluation (RLSE) with selected life science experiments, and (e) Biomedical Experiments Scientific Satellite (BESS) - extended duration primate (Type I) and small vertebrate (Type II) missions. The recommended operational methods described in the paper are compared to the fundamental data which has been developed in the life science Spacelab Mission Simulation (SMS) test series. Areas assessed include crew training, experiment development and integration, testing, data-dissemination, organization interfaces, and principal investigator working relationships.
Noh, Jin-Won; Park, Hyunchun; Kim, Minji; Kwon, Young Dae; Kim, Jin-Seok; Yu, Shieun
2018-01-01
This study investigated the mediation effect of stress between the experience of discrimination and life satisfaction among North Korean refugees who resettled in South Korea. The findings of the current study provide empirical evidence for the need of social interventions to mitigate adverse effects of stress on North Korean refugees who are subject to social discrimination on a daily basis. In this study, we included 500 subjects among 2,138 North Korean refugees who took refuge in South Korea in 2007. The interview started from April 6th 2009 and finished on May 25th 2009. We conducted moderator effect analysis with Path analysis was conducted because we confirm the experience of discrimination was affected by life satisfaction and stress can affected life satisfaction as a moderator. The experience of discrimination significantly affects stress and stress significantly affects life satisfaction. However, the experience of discrimination was not directly related to life satisfaction. The more stress the study respondents experienced, the lower the life satisfaction they reported. The present finding suggests that the effects of discriminating experiences on the life satisfaction of North Korean refugees in South Korea were mediated by their own perceived stress.
S3: School Zone Safety System Based on Wireless Sensor Network
Yoo, Seong-eun; Chong, Poh Kit; Kim, Daeyoung
2009-01-01
School zones are areas near schools that have lower speed limits and where illegally parked vehicles pose a threat to school children by obstructing them from the view of drivers. However, these laws are regularly flouted. Thus, we propose a novel wireless sensor network application called School zone Safety System (S3) to help regulate the speed limit and to prevent illegal parking in school zones. S3 detects illegally parked vehicles, and warns the driver and records the license plate number. To reduce the traveling speed of vehicles in a school zone, S3 measures the speed of vehicles and displays the speed to the driver via an LED display, and also captures the image of the speeding vehicle with a speed camera. We developed a state machine based vehicle detection algorithm for S3. From extensive experiments in our testbeds and data from a real school zone, it is shown that the system can detect all kinds of vehicles, and has an accuracy of over 95% for speed measurement. We modeled the battery life time of a sensor node and validated the model with a downscaled measurement; we estimate the battery life time to be over 2 years. We have deployed S3 in 15 school zones in 2007, and we have demonstrated the robustness of S3 by operating them for over 1 year. PMID:22454567
NASA Astrophysics Data System (ADS)
Li, Jiangtong; Luo, Yongdao; Dai, Honglin
2018-01-01
Water is the source of life and the essential foundation of all life. With the development of industrialization, the phenomenon of water pollution is becoming more and more frequent, which directly affects the survival and development of human. Water quality detection is one of the necessary measures to protect water resources. Ultraviolet (UV) spectral analysis is an important research method in the field of water quality detection, which partial least squares regression (PLSR) analysis method is becoming predominant technology, however, in some special cases, PLSR's analysis produce considerable errors. In order to solve this problem, the traditional principal component regression (PCR) analysis method was improved by using the principle of PLSR in this paper. The experimental results show that for some special experimental data set, improved PCR analysis method performance is better than PLSR. The PCR and PLSR is the focus of this paper. Firstly, the principal component analysis (PCA) is performed by MATLAB to reduce the dimensionality of the spectral data; on the basis of a large number of experiments, the optimized principal component is extracted by using the principle of PLSR, which carries most of the original data information. Secondly, the linear regression analysis of the principal component is carried out with statistic package for social science (SPSS), which the coefficients and relations of principal components can be obtained. Finally, calculating a same water spectral data set by PLSR and improved PCR, analyzing and comparing two results, improved PCR and PLSR is similar for most data, but improved PCR is better than PLSR for data near the detection limit. Both PLSR and improved PCR can be used in Ultraviolet spectral analysis of water, but for data near the detection limit, improved PCR's result better than PLSR.
de Marcellus, Pierre; Bertrand, Marylène; Nuevo, Michel; Westall, Frances; Le Sergeant d'Hendecourt, Louis
2011-11-01
The delivery of extraterrestrial organic materials to primitive Earth from meteorites or micrometeorites has long been postulated to be one of the origins of the prebiotic molecules involved in the subsequent apparition of life. Here, we report on experiments in which vacuum UV photo-irradiation of interstellar/circumstellar ice analogues containing H(2)O, CH(3)OH, and NH(3) led to the production of several molecules of prebiotic interest. These were recovered at room temperature in the semi-refractory, water-soluble residues after evaporation of the ice. In particular, we detected small quantities of hydantoin (2,4-imidazolidinedione), a species suspected to play an important role in the formation of poly- and oligopeptides. In addition, hydantoin is known to form under extraterrestrial, abiotic conditions, since it has been detected, along with various other derivatives, in the soluble part of organic matter of primitive carbonaceous meteorites. This result, together with other related experiments reported recently, points to the potential importance of the photochemistry of interstellar "dirty" ices in the formation of organics in Solar System materials. Such molecules could then have been delivered to the surface of primitive Earth, as well as other telluric (exo-) planets, to help trigger first prebiotic reactions with the capacity to lead to some form of primitive biomolecular activity.
Biota and Biomolecules in Extreme Environments on Earth: Implications for Life Detection on Mars
Aerts, Joost W.; Röling, Wilfred F.M.; Elsaesser, Andreas; Ehrenfreund, Pascale
2014-01-01
The three main requirements for life as we know it are the presence of organic compounds, liquid water, and free energy. Several groups of organic compounds (e.g., amino acids, nucleobases, lipids) occur in all life forms on Earth and are used as diagnostic molecules, i.e., biomarkers, for the characterization of extant or extinct life. Due to their indispensability for life on Earth, these biomarkers are also prime targets in the search for life on Mars. Biomarkers degrade over time; in situ environmental conditions influence the preservation of those molecules. Nonetheless, upon shielding (e.g., by mineral surfaces), particular biomarkers can persist for billions of years, making them of vital importance in answering questions about the origins and limits of life on early Earth and Mars. The search for organic material and biosignatures on Mars is particularly challenging due to the hostile environment and its effect on organic compounds near the surface. In support of life detection on Mars, it is crucial to investigate analogue environments on Earth that resemble best past and present Mars conditions. Terrestrial extreme environments offer a rich source of information allowing us to determine how extreme conditions affect life and molecules associated with it. Extremophilic organisms have adapted to the most stunning conditions on Earth in environments with often unique geological and chemical features. One challenge in detecting biomarkers is to optimize extraction, since organic molecules can be low in abundance and can strongly adsorb to mineral surfaces. Methods and analytical tools in the field of life science are continuously improving. Amplification methods are very useful for the detection of low concentrations of genomic material but most other organic molecules are not prone to amplification methods. Therefore, a great deal depends on the extraction efficiency. The questions “what to look for”, “where to look”, and “how to look for it” require more of our attention to ensure the success of future life detection missions on Mars. PMID:25370528
Biota and biomolecules in extreme environments on Earth: implications for life detection on Mars.
Aerts, Joost W; Röling, Wilfred F M; Elsaesser, Andreas; Ehrenfreund, Pascale
2014-10-13
The three main requirements for life as we know it are the presence of organic compounds, liquid water, and free energy. Several groups of organic compounds (e.g., amino acids, nucleobases, lipids) occur in all life forms on Earth and are used as diagnostic molecules, i.e., biomarkers, for the characterization of extant or extinct life. Due to their indispensability for life on Earth, these biomarkers are also prime targets in the search for life on Mars. Biomarkers degrade over time; in situ environmental conditions influence the preservation of those molecules. Nonetheless, upon shielding (e.g., by mineral surfaces), particular biomarkers can persist for billions of years, making them of vital importance in answering questions about the origins and limits of life on early Earth and Mars. The search for organic material and biosignatures on Mars is particularly challenging due to the hostile environment and its effect on organic compounds near the surface. In support of life detection on Mars, it is crucial to investigate analogue environments on Earth that resemble best past and present Mars conditions. Terrestrial extreme environments offer a rich source of information allowing us to determine how extreme conditions affect life and molecules associated with it. Extremophilic organisms have adapted to the most stunning conditions on Earth in environments with often unique geological and chemical features. One challenge in detecting biomarkers is to optimize extraction, since organic molecules can be low in abundance and can strongly adsorb to mineral surfaces. Methods and analytical tools in the field of life science are continuously improving. Amplification methods are very useful for the detection of low concentrations of genomic material but most other organic molecules are not prone to amplification methods. Therefore, a great deal depends on the extraction efficiency. The questions "what to look for", "where to look", and "how to look for it" require more of our attention to ensure the success of future life detection missions on Mars.
Design Tools for Cost-Effective Implementation of Planetary Protection Requirements
NASA Technical Reports Server (NTRS)
Hamlin, Louise; Belz, Andrea; Evans, Michael; Kastner, Jason; Satter, Celeste; Spry, Andy
2006-01-01
Since the Viking missions to Mars in the 1970s, accounting for the costs associated with planetary protection implementation has not been done systematically during early project formulation phases, leading to unanticipated costs during subsequent implementation phases of flight projects. The simultaneous development of more stringent planetary protection requirements, resulting from new knowledge about the limits of life on Earth, together with current plans to conduct life-detection experiments on a number of different solar system target bodies motivates a systematic approach to integrating planetary protection requirements and mission design. A current development effort at NASA's Jet Propulsion Laboratory is aimed at integrating planetary protection requirements more fully into the early phases of mission architecture formulation and at developing tools to more rigorously predict associated cost and schedule impacts of architecture options chosen to meet planetary protection requirements.
Dissipation kinetics of bifenazate in tea under tropical conditions.
Satheshkumar, Annamalai; Senthurpandian, Velu Kalaipandian; Shanmugaselvan, Veilumuthu Anandham
2014-02-15
Field experiments were conducted during April and May of 2011 in Valparai, Coonoor and Gudalur (Tamil Nadu, India) to determine the residues of bifenazate in black tea. From this study, residue levels of bifenazate at different harvest intervals, persistence, dissipation pattern during processing, rate constant and half-life values were calculated. Residues of bifenazate dissipated exponentially after spraying and at Gudalur trial, on the 16th day after application residues were below the maximum residue level of 0.02 mg/kg set by the European Union. However, no residues were detected in the tea brew. Regression lines drawn for bifenazate showed that it followed first order dissipation kinetics. Half-life values varied from 1.03 to 1.36 days for bifenazate and a pre-harvest interval of 16 days is suggested. Copyright © 2013 Elsevier Ltd. All rights reserved.
A software engineering approach to expert system design and verification
NASA Technical Reports Server (NTRS)
Bochsler, Daniel C.; Goodwin, Mary Ann
1988-01-01
Software engineering design and verification methods for developing expert systems are not yet well defined. Integration of expert system technology into software production environments will require effective software engineering methodologies to support the entire life cycle of expert systems. The software engineering methods used to design and verify an expert system, RENEX, is discussed. RENEX demonstrates autonomous rendezvous and proximity operations, including replanning trajectory events and subsystem fault detection, onboard a space vehicle during flight. The RENEX designers utilized a number of software engineering methodologies to deal with the complex problems inherent in this system. An overview is presented of the methods utilized. Details of the verification process receive special emphasis. The benefits and weaknesses of the methods for supporting the development life cycle of expert systems are evaluated, and recommendations are made based on the overall experiences with the methods.
Exoplanet Biosignatures: Future Directions.
Walker, Sara I; Bains, William; Cronin, Leroy; DasSarma, Shiladitya; Danielache, Sebastian; Domagal-Goldman, Shawn; Kacar, Betul; Kiang, Nancy Y; Lenardic, Adrian; Reinhard, Christopher T; Moore, William; Schwieterman, Edward W; Shkolnik, Evgenya L; Smith, Harrison B
2018-06-01
We introduce a Bayesian method for guiding future directions for detection of life on exoplanets. We describe empirical and theoretical work necessary to place constraints on the relevant likelihoods, including those emerging from better understanding stellar environment, planetary climate and geophysics, geochemical cycling, the universalities of physics and chemistry, the contingencies of evolutionary history, the properties of life as an emergent complex system, and the mechanisms driving the emergence of life. We provide examples for how the Bayesian formalism could guide future search strategies, including determining observations to prioritize or deciding between targeted searches or larger lower resolution surveys to generate ensemble statistics and address how a Bayesian methodology could constrain the prior probability of life with or without a positive detection. Key Words: Exoplanets-Biosignatures-Life detection-Bayesian analysis. Astrobiology 18, 779-824.
[The influence of meaning making following stressful life experiences on change of self-concept].
Horita, Ryo; Sugie, Masashi
2013-10-01
As interest in meaning making following stressful life experiences continues to grow, it is important to clarify the features and functions of the meaning- making process. We examined the influence of meaning making following stressful life experiences on change of self-concept. In two studies, university students selected their most stressful life experience and completed the Assimilation and Accommodation of Meaning Making Scale. In Study 1, 235 university students also completed questionnaires regarding post-traumatic growth and positive change of the sense of identity following their stressful life experience. The results of covariance structure analysis indicated that accommodation promoted a positive change of self-concept. In Study 2, 199 university students completed questionnaires regarding change of self-concept and emotion as a positive or negative change following stressful life experiences. The results of covariance structure analysis indicated that accommodation promoted a positive change, similar to the results of Study 1. In addition, accommodation also promoted negative change. However, assimilation did not promote positive change but did restrain negative change.
Gas and water recycling system for IOC vivarium experiments
NASA Technical Reports Server (NTRS)
Nitta, K.; Otsubo, K.
1986-01-01
Water and gas recycling units designed as one of the common experiment support system for the life science experiment facilities used in the Japanese Experiment Module are discussed. These units will save transportation and operation costs for the life science experiments in the space station. These units are also designed to have interfaces so simple that the connection to another life science experiment facilities such as the Research Animal Holding Facility developed by the Rockheed Missiles and Space Company can be easily done with small modification.
Behavior analysis for elderly care using a network of low-resolution visual sensors
NASA Astrophysics Data System (ADS)
Eldib, Mohamed; Deboeverie, Francis; Philips, Wilfried; Aghajan, Hamid
2016-07-01
Recent advancements in visual sensor technologies have made behavior analysis practical for in-home monitoring systems. The current in-home monitoring systems face several challenges: (1) visual sensor calibration is a difficult task and not practical in real-life because of the need for recalibration when the visual sensors are moved accidentally by a caregiver or the senior citizen, (2) privacy concerns, and (3) the high hardware installation cost. We propose to use a network of cheap low-resolution visual sensors (30×30 pixels) for long-term behavior analysis. The behavior analysis starts by visual feature selection based on foreground/background detection to track the motion level in each visual sensor. Then a hidden Markov model (HMM) is used to estimate the user's locations without calibration. Finally, an activity discovery approach is proposed using spatial and temporal contexts. We performed experiments on 10 months of real-life data. We show that the HMM approach outperforms the k-nearest neighbor classifier against ground truth for 30 days. Our framework is able to discover 13 activities of daily livings (ADL parameters). More specifically, we analyze mobility patterns and some of the key ADL parameters to detect increasing or decreasing health conditions.
Lunar and Planetary Science XXXV: Astrobiology: Analogs and Applications to the Search for Life
NASA Technical Reports Server (NTRS)
2004-01-01
The session "Astrobiology: Analogs and Applications to the Search for Life" included the folowing reports:The Search for Life on Mars Using Macroscopically Visible Microbial Mats (Stromatolites) in 3.5/3.3 Ga Cherts from the Pilbara in Australia and Barberton in South Africa as Analogues; Life in a Mars Analog: Microbial Activity Associated with Carbonate Cemented Lava Breccias from NW Spitsbergen; Groundwater-fed Iron-rich Microbial Mats in a Freshwater Creek: Growth Cycles and Fossilization Potential of Microbial Features; Episodic Fossilization of Microorganisms on an Annual Timescale in an Anthropogenically Modified Natural Environment: Geochemical Controls and Implications for Astrobiology; Proterozoic Microfossils and Their Implications for Recognizing Life on Mars; Microbial Alteration of Volcanic Glass in Modern and Ancient Oceanic Crust as a Proxy for Studies of Extraterrestrial Material ; Olivine Alteration on Earth and Mars; Searching for an Acidic Aquifer in the R!o Tinto Basin. First Geobiology Results of MARTE Project; In-Field Testing of Life Detection Instruments and Protocols in a Mars Analogue Arctic Environment; Habitability of the Shallow Subsurface on Mars: Clues from the Meteorites; Mars Analog Rio Tinto Experiment (MARTE): 2003 Drilling Campaign to Search for a Subsurface Biosphere at Rio Tinto Spain; Characterization of the Organic Matter in an Archean Chert (Warrawoona, Australia); and The Solfatara Crater, Italy: Characterization of Hydrothermal Deposits, Biosignatures and Their Astrobiological Implication.
Dietary restraint and subjective well-being in university students in Chile.
Schnettler, Berta; Miranda, Horacio; Sepúlveda, José; Orellana, Ligia; Etchebarne, Soledad; Lobos, Germán; Mora, Marcos; Denegri, Marianela; Grunert, Klaus G
2014-08-01
To characterize university students typologies according to chronic food restriction, satisfaction with life and food consumption. A questionnaire was applied on a non-probability sample of 369 male and female students from five Chilean universities. The questionnaire included: Revised Restraint Scale (RRS), Satisfaction with Life Scale (SWLS), Satisfaction with Food-related Life (SWFL) and the Health-related Quality of Life Index. The survey included food and drink consumption habits, weight and approximate height and sociodemographic variables. Two factors in the RRS were detected by exploratory factor analysis: Preoccupation with Diet (PD) and Weight fluctuations (WF). A confirmatory factor analysis validated the bifactor structure of the RRS with an acceptable adjustment kindness. The cluster analysis allowed a distinction of four typologies with a significant variation in PD, WF, SWLS and SWFL scoring, number of days with mental health problems, frequency of alcoholic drinks consumption, restraint on the consumption of certain foods, drinks and spices, consumption frequency of fruit out of the main meals and types. Typologies did not differ on their body mass index. Both, students preoccupied with diet and those who are not, experience higher levels of satisfaction with life and with food. Lower levels of global life satisfaction and satisfaction with food are related with the fluctuations in weight. Copyright AULA MEDICA EDICIONES 2014. Published by AULA MEDICA. All rights reserved.
Taylor, Mark A; Cooper, Martha D; Sellamuthu, Reena; Braun, Peter; Migneault, Andrew; Browning, Alyssa; Perry, Emily; Schmitt, Johanna
2017-10-01
Major alleles for seed dormancy and flowering time are well studied, and can interact to influence seasonal timing and fitness within generations. However, little is known about how this interaction controls phenology, life history, and population fitness across multiple generations in natural seasonal environments. To examine how seed dormancy and flowering time shape annual plant life cycles over multiple generations, we established naturally dispersing populations of recombinant inbred lines of Arabidopsis thaliana segregating early and late alleles for seed dormancy and flowering time in a field experiment. We recorded seasonal phenology and fitness of each genotype over 2 yr and several generations. Strong seed dormancy suppressed mid-summer germination in both early- and late-flowering genetic backgrounds. Strong dormancy and late-flowering genotypes were both necessary to confer a winter annual life history; other genotypes were rapid-cycling. Strong dormancy increased within-season fecundity in an early-flowering background, but decreased it in a late-flowering background. However, there were no detectable differences among genotypes in population growth rates. Seasonal phenology, life history, and cohort fitness over multiple generations depend strongly upon interacting genetic variation for dormancy and flowering. However, similar population growth rates across generations suggest that different life cycle genotypes can coexist in natural populations. © 2017 The Authors. New Phytologist © 2017 New Phytologist Trust.
Developmental trends in infant temporal processing speed.
Saint, Sarah E; Hammond, Billy R; O'Brien, Kevin J; Frick, Janet E
2017-09-01
Processing speed, which can be measured behaviorally in various sensory domains, has been shown to be a strong marker of central nervous system health and functioning in adults. Visual temporal processing speed (measured via critical flicker fusion [CFF] thresholds) represents the maximum speed at which the visual system can detect changes. Previous studies of infant CFF development have been limited and inconsistent. The present study sought to characterize the development of CFF thresholds in the first year of life using a larger sample than previous studies and a repeated measures design (in Experiment 2) to control for individual differences. Experiment 1 (n=44 infants and n=24 adults) used a cross-sectional design aimed at examining age-related changes that exist in CFF thresholds across infants during the first year of life. Adult data were collected to give context to infant CFF thresholds obtained under our specific stimulus conditions. Experiment 2 (N=28) used a repeated-measures design to characterize the developmental trajectory of infant CFF thresholds between three and six months of age, based on the results of Experiment 1. Our results reveal a general increase in CFF from three to four and one-half months of age, with a high degree of variability within each age group. Infant CFF thresholds at 4.5months of age were not significantly different from the adult average, though a regression analysis of the data from Experiment 2 predicted that infants would reach the adult average closer to 6months of age. Developmental and clinical implications of these data are discussed. Published by Elsevier Ltd.
NASA Johnson Space Center Life Sciences Data System
NASA Technical Reports Server (NTRS)
Rahman, Hasan; Cardenas, Jeffery
1994-01-01
The Life Sciences Project Division (LSPD) at JSC, which manages human life sciences flight experiments for the NASA Life Sciences Division, augmented its Life Sciences Data System (LSDS) in support of the Spacelab Life Sciences-2 (SLS-2) mission, October 1993. The LSDS is a portable ground system supporting Shuttle, Spacelab, and Mir based life sciences experiments. The LSDS supports acquisition, processing, display, and storage of real-time experiment telemetry in a workstation environment. The system may acquire digital or analog data, storing the data in experiment packet format. Data packets from any acquisition source are archived and meta-parameters are derived through the application of mathematical and logical operators. Parameters may be displayed in text and/or graphical form, or output to analog devices. Experiment data packets may be retransmitted through the network interface and database applications may be developed to support virtually any data packet format. The user interface provides menu- and icon-driven program control and the LSDS system can be integrated with other workstations to perform a variety of functions. The generic capabilities, adaptability, and ease of use make the LSDS a cost-effective solution to many experiment data processing requirements. The same system is used for experiment systems functional and integration tests, flight crew training sessions and mission simulations. In addition, the system has provided the infrastructure for the development of the JSC Life Sciences Data Archive System scheduled for completion in December 1994.
The cryogenic dark matter search low ionization-threshold experiment
NASA Astrophysics Data System (ADS)
Basu Thakur, Ritoban
Over 80 years ago we discovered the presence of Dark Matter in our universe. Endeavors in astronomy and cosmology are in consensus with ever improving precision that Dark Matter constitutes an essential 27% of our universe. The Standard Model of Particle Physics does not provide any answers to the Dark Matter problem. It is imperative that we understand Dark Matter and discover its fundamental nature. This is because, alongside other important factors, Dark Matter is responsible for formation of structure in our universe. The very construct in which we sit is defined by its abundance. The Milky Way galaxy, hence life, wouldn't have formed if small over densities of Dark Matter had not caused sufficient accretion of stellar material. Marvelous experiments have been designed based on basic notions to directly and indirectly study Dark Matter, and the Cryogenic Dark Matter Search (CDMS) experiment has been a pioneer and forerunner in the direct detection field. Generations of the CDMS experiment were designed with advanced scientific upgrades to detect Dark Matter particles of mass O(100) GeV/c2. This mass-scale was set primarily by predictions from Super Symmetry. Around 2013 the canonical SUSY predictions were losing some ground and several observations (rather hints of signals) from various experiments indicated to the possibility of lighter Dark Matter of mass O(10) GeV/c2. While the SuperCDMS experiment was probing the regular parameter space, the CDMSlite experiment was conceived to dedicatedly search for light Dark Matter using a novel technology. "CDMSlite" stands for CDMS - low ionization threshold experiment. Here we utilize a unique electron phonon coupling mechanism to measure ionization generated by scattering of light particles. Typically signals from such low energy recoils would be washed under instrumental noise.In CDMSlite via generation of Luke-Neganov phonons we can detect the small ionization energies, amplified in phonon modes during charge transport. This technology allows us to reach very low thresholds and reliably measure and investigate low energy recoils from light Dark Matter particles. This thesis describes the physics behind CDMSlite, the experimenta design and the first science results from CDMSlite operated at the Soudan Underground Laboratory.
The Cryogenic Dark Matter Search low ionization-threshold experiment
DOE Office of Scientific and Technical Information (OSTI.GOV)
Basu Thakur, Ritoban
2014-01-01
Over 80 years ago we discovered the presence of Dark Matter in our universe. Endeavors in astronomy and cosmology are in consensus with ever improving precision that Dark Matter constitutes an essential 27% of our universe. The Standard Model of Particle Physics does not provide any answers to the Dark Matter problem. It is imperative that we understand Dark Matter and discover its fundamental nature. This is because, alongside other important factors, Dark Matter is responsible for formation of structure in our universe. The very construct in which we sit is defined by its abundance. The Milky Way galaxy, hencemore » life, wouldn't have formed if small over densities of Dark Matter had not caused sufficient accretion of stellar material. Marvelous experiments have been designed based on basic notions to directly and in-directly study Dark Matter, and the Cryogenic Dark Matter Search (CDMS) experiment has been a pioneer and forerunner in the direct detection field. Generations of the CDMS experiment were designed with advanced scientific upgrades to detect Dark Matter particles of mass O(100) GeV/c 2. This mass-scale was set primarily by predictions from Super Symmetry. Around 2013 the canonical SUSY predictions were losing some ground and several observations (rather hints of signals) from various experiments indicated to the possibility of lighter Dark Matter of mass O(10) GeV/c 2. While the SuperCDMS experiment was probing the regular parameter space, the CDMSlite experiment was conceived to dedicatedly search for light Dark Matter using a novel technology. "CDMSlite" stands for CDMS - low ionization threshold experiment. Here we utilize a unique electron phonon coupling mechanism to measure ionization generated by scattering of light particles. Typically signals from such low energy recoils would be washed under instrumental noise. In CDMSlite via generation of Luke-Neganov phonons we can detect the small ionization energies, amplified in phonon modes during charge transport. This technology allows us to reach very low thresholds and reliably measure and investigate low energy recoils from light Dark Matter particles. This thesis describes the physics behind CDMSlite, the experimental design and the first science results from CDMSlite operated at the Soudan Underground Laboratory.« less
Electrochemical Detection of the Molecules of Life
NASA Technical Reports Server (NTRS)
Thomson, Seamus; Quinn, Richard; Koehne, Jessica
2017-01-01
All forms of life on Earth contain cellular machinery that can transform and regulate chemical energy through metabolic pathways. These processes are oxidation-reduction reactions that are performed by four key classes of molecules: flavins, nicotinamaides, porphyrins, and quinones. By detecting the electrochemical interaction of these redox-active molecules with an electrode, a method of differentiating them by their class could be established and incorporated into future life-detecting missions. This body of work investigates the electrochemistry of ubiquitous molecules found in life and how they may be detected. Molecules can oxidise or reduce the surface of an electrode - giving or receiving electrons - and these interactions are represented by changes in current with respect to an applied voltage. This relationship varies with: electrolyte type and concentration, working electrode material, the redox-active molecule itself, and scan rate. Flavin adenine dinucleotide (FAD), riboflavin, nicotinamide adenine dinucleotide (NADH), and anthraquinone are all molecules found intracellularly in almost all living organisms. An organism-synthesised extracellular redox-active molecule, Plumbagin, was also selected as part of this study. The goal of this work is to detect these molecules in seawater and assess its application in searching for life on Ocean Worlds.
Liyanage, Rohana; Devarapalli, Nagarjuna; Pyland, Derek B; Puckett, Latisha M; Phan, N H; Starch, Joel A; Okimoto, Mark R; Gidden, Jennifer; Stites, Wesley E; Lay, Jackson O
2012-12-15
Protein equilibrium snapshot by hydrogen/deuterium exchange electrospray ionization mass spectrometry (PEPS-HDX-ESI-MS or PEPS) is a method recently introduced for estimating protein folding energies and rates. Herein we describe the basis for this method using both theory and new experiments. Benchmark experiments were conducted using ubiquitin because of the availability of reference data for folding and unfolding rates from NMR studies. A second set of experiments was also conducted to illustrate the surprising resilience of the PEPS to changes in HDX time, using staphylococcal nuclease and time frames ranging from a few seconds to several minutes. Theory suggests that PEPS experiments should be conducted at relatively high denaturant concentrations, where the protein folding/unfolding rates are slow with respect to HDX and the life times of both the closed and open states are long enough to be sampled experimentally. Upon deliberate denaturation, changes in folding/unfolding are correlated with associated changes in the ESI-MS signal upon fast HDX. When experiments are done quickly, typically within a few seconds, ESI-MS signals, corresponding to the equilibrium population of the native (closed) and denatured (open) states can both be detected. The interior of folded proteins remains largely un-exchanged. Amongst MS methods, the simultaneous detection of both states in the spectrum is unique to PEPS and provides a "snapshot" of these populations. The associated ion intensities are used to estimate the protein folding equilibrium constant (or the free energy change, ΔG). Linear extrapolation method (LEM) plots of derived ΔG values for each denaturant concentration can then be used to calculate ΔG in the absence of denaturant, ΔG(H(2)O). In accordance with the requirement for detection of signals for both the folded and unfolded states, this theoretical framework predicts that PEPS experiments work best at the middle of the denaturation curve where natured and denatured protein molecules are equilibrated at easily detectable ratios, namely 1:1. It also requires that closed and open states have lifetimes measurable in the time frame of the HDX experiment. Because both conditions are met by PEPS, these measurements can provide an accurate assessment of closed/open state populations and thus protein folding energies/rates.
Brox, Stephan; Seiwert, Bettina; Haase, Nora; Küster, Eberhard; Reemtsma, Thorsten
2016-01-01
The zebrafish embryo (ZFE) is increasingly used in ecotoxicology research but detailed knowledge of its metabolic potential is still limited. This study focuses on the xenobiotic metabolism of ZFE at different life-stages using the pharmaceutical compound clofibric acid as study compound. Liquid chromatography with quadrupole-time-of-flight mass spectrometry (LC-QToF-MS) is used to detect and to identify the transformation products (TPs). In screening experiments, a total of 18 TPs was detected and structure proposals were elaborated for 17 TPs, formed by phase I and phase II metabolism. Biotransformation of clofibric acid by the ZFE involves conjugation with sulfate or glucuronic acid, and, reported here for the first time, with carnitine, taurine, and aminomethanesulfonic acid. Further yet unknown cyclization products were identified using non-target screening that may represent a new detoxification pathway. Sulfate containing TPs occurred already after 3h of exposure (7hpf), and from 48h of exposure (52hpf) onwards, all TPs were detected. The detection of these TPs indicates the activity of phase I and phase II enzymes already at early life-stages. Additionally, the excretion of one TP into the exposure medium was observed. The results of this study outline the high metabolic potential of the ZFE with respect to the transformation of xenobiotics. Similarities but also differences to other test systems were observed. Biotransformation of test chemicals in toxicity testing with ZFE may therefore need further consideration. Copyright © 2016 Elsevier Inc. All rights reserved.
Enzymatic Activity Detection via Electrochemistry for Enceladus
NASA Technical Reports Server (NTRS)
Studemeister, Lucy; Koehne, Jessica; Quinn, Richard
2017-01-01
Electrochemical detection of biological molecules is a pertinent topic and application in many fields such as medicine, environmental spills, and life detection in space. Proteases, a class of molecules of interest in the search for life, catalyze the hydrolysis of peptides. Trypsin, a specific protease, was chosen to investigate an optimized enzyme detection system using electrochemistry. This study aims at providing the ideal functionalization of an electrode that can reliably detect a signal indicative of an enzymatic reaction from an Enceladus sample.
Social learning improves survivorship at a life-history transition.
Manassa, R P; McCormick, M I
2013-04-01
During settlement, one of the main threats faced by individuals relates to their ability to detect and avoid predators. Information on predator identities can be gained either through direct experience or from the observation and/or interaction with others, a process known as social learning. In this form of predator recognition, less experienced individuals learn from experienced members within the social group, without having to directly interact with a predator. In this study, we examined the role of social learning in predator recognition in relation to the survival benefits for the damselfish, Pomacentrus wardi, during their settlement transition. Specifically, our experiments aimed to determine if P. wardi are capable of transmitting the recognition of the odour of a predator, Pseudochromis fuscus, to conspecifics. The experiment also examined whether there was a difference in the rate of survival between individuals that directly learnt the predator odour and those which acquired the information through social learning compared to naïve individuals. Results show that naïve P. wardi are able to learn a predator's identity from experienced individuals via social learning. Furthermore, survival between individuals that directly learnt the predator's identity and those that learnt through social learning did not significantly differ, with fish from both treatments surviving at least five times better than controls. These results demonstrate that experience may play a vital role in determining the outcome of predator-prey interactions, highlighting that social learning improves the ability of prey to avoid and/or escape predation at a life-history transition.
The use of biochemical methods in extraterrestrial life detection
NASA Astrophysics Data System (ADS)
McDonald, Gene
2006-08-01
Instrument development for in situ extraterrestrial life detection focuses primarily on the ability to distinguish between biological and non-biological material, mostly through chemical analysis for potential biosignatures (e.g., biogenic minerals, enantiomeric excesses). In constrast, biochemical analysis techniques commonly applied to Earth life focus primarily on the exploration of cellular and molecular processes, not on the classification of a given system as biological or non-biological. This focus has developed because of the relatively large functional gap between life and non-life on Earth today. Life on Earth is very diverse from an environmental and physiological point of view, but is highly conserved from a molecular point of view. Biochemical analysis techniques take advantage of this similarity of all terrestrial life at the molecular level, particularly through the use of biologically-derived reagents (e.g., DNA polymerases, antibodies), to enable analytical methods with enormous sensitivity and selectivity. These capabilities encourage consideration of such reagents and methods for use in extraterrestrial life detection instruments. The utility of this approach depends in large part on the (unknown at this time) degree of molecular compositional differences between extraterrestrial and terrestrial life. The greater these differences, the less useful laboratory biochemical techniques will be without significant modification. Biochemistry and molecular biology methods may need to be "de-focused" in order to produce instruments capable of unambiguously detecting a sufficiently wide range of extraterrestrial biochemical systems. Modern biotechnology tools may make that possible in some cases.
NASA Astrophysics Data System (ADS)
Stoker, C. R.; Stevens, T.; Amils, R.; Fernandez, D.
2005-12-01
Biological systems on Earth require three key ingredients-- liquid water, an energy source, and a carbon source, that are found in very few extraterrestrial environments. Previous examples of independent subsurface ecosystems have been found only in basalt aquifers. Such lithotrophic microbial ecosystems (LME) have been proposed as models for steps in the early evolution of Earth's biosphere and for potential biospheres on other planets where the surface is uninhabitable, such as Mars and Europa.. The Mars Analog Rio Tinto Experiment (MARTE) has searched in a volcanic massive sulfide deposit in Rio Tinto Spain for a subsurface biosphere capable of living without sunlight or oxygen and found a subsurface ecosystem driven by the weathering of the massive sulfide deposit (VMS) in which the rock matrix provides sufficient resources to support microbial metabolism, including the vigorous production of H2 by water-rock interactions. Microbial production of methane and sulfate occurred in the sulfide orebody and microbial production of methane and hydrogen sulfide continued in an anoxic plume downgradient from the sulfide ore. Organic carbon concentrations in the parent rock were too low to support microbes. The Rio Tinto system thus represents a new type of subsurface ecosystem with strong relevance for exobiological studies. Commercial drilling was used to reach the aquifer system at 100 m depth and conventional laboratory techniques were used to identify and characterize the biosphere. Then, the life search strategy that led to successful identification of this biosphere was applied to the development of a robotic drilling, core handling, inspection, subsampling, and life detection system built on a prototype planetary lander that was deployed in Rio Tinto Spain in September 2005 to test the capability of a robotic drilling system to search for subsurface life. A remote science team directed the simulation and analyzed the data from the MARTE robotic drill. The results of this experiment have important implications for the strategy for searching for life on Mars.
Patients' experiences of everyday life after lung transplantation.
Thomsen, Doris; Jensen, Birte Østergaard
2009-12-01
To investigate the experiences of everyday life after lung transplantation of patients with previous chronic obstructive pulmonary disease (COPD). Compared with patients being transplanted due to other indications, those with COPD prior to lung transplantation report more problems in the form of shortness of breath, fatigue, sexual problems, insomnia and increased appetite. In addition, they are often faced with problems returning to normal working life. How these problems influence the patient's everyday life is unknown. An exploratory qualitative study. Ten COPD patients (five females and five males) aged 51-69 and more than six months post transplantation, were interviewed using of a semi-structured interview guide. All interviews were taperecorded, transcribed verbatim and analysed using qualitative content analysis. The analysis revealed four themes of experience: a second chance; an ordinary life without chronic rejection; even minor daily activities take time with chronic rejection; and need for support and knowledge that were considered important by the participants for their situation and daily life. This is the first study describing the experiences of everyday life after lung transplantation of patients with COPD prior to surgery. The findings highlight the importance of addressing these patients' experiences of gratitude, positive life orientation and informational needs in relation to everyday life. Health professionals should be aware of the kind of problems both women and men may experience a long time after the lung transplantation. They constitute a basic knowledge of a patient's everyday life that is important when planning individual counselling and rehabilitation.
Cowling, Benjamin J.; Koh, Gerald C.; Chu, Daniel; Heilbronn, Cherie; Lloyd, Belinda; Pantelic, Jovan; Nicolle, Andre D.; Klettner, Christian A.; Peiris, J. S. Malik; Sekhar, Chandra; Cheong, David K. W.; Tham, Kwok Wai; Koay, Evelyn S. C.; Tsui, Wendy; Kwong, Alfred; Chan, Kitty; Li, Yuguo
2014-01-01
Two independent studies by two separate research teams (from Hong Kong and Singapore) failed to detect any influenza RNA landing on, or inhaled by, a life-like, human manikin target, after exposure to naturally influenza-infected volunteers. For the Hong Kong experiments, 9 influenza-infected volunteers were recruited to breathe, talk/count and cough, from 0.1 m and 0.5 m distance, onto a mouth-breathing manikin. Aerosolised droplets exhaled from the volunteers and entering the manikin’s mouth were collected with PTFE filters and an aerosol sampler, in separate experiments. Virus detection was performed using an in-house influenza RNA reverse-transcription polymerase chain reaction (RT-PCR) assay. No influenza RNA was detected from any of the PTFE filters or air samples. For the Singapore experiments, 6 influenza-infected volunteers were asked to breathe (nasal/mouth breathing), talk (counting in English/second language), cough (from 1 m/0.1 m away) and laugh, onto a thermal, breathing manikin. The manikin’s face was swabbed at specific points (around both eyes, the nostrils and the mouth) before and after exposure to each of these respiratory activities, and was cleaned between each activity with medical grade alcohol swabs. Shadowgraph imaging was used to record the generation of these respiratory aerosols from the infected volunteers and their impact onto the target manikin. No influenza RNA was detected from any of these swabs with either team’s in-house diagnostic influenza assays. All the influenza-infected volunteers had diagnostic swabs taken at recruitment that confirmed influenza (A/H1, A/H3 or B) infection with high viral loads, ranging from 105-108 copies/mL (Hong Kong volunteers/assay) and 104–107 copies/mL influenza viral RNA (Singapore volunteers/assay). These findings suggest that influenza RNA may not be readily transmitted from naturally-infected human source to susceptible recipients via these natural respiratory activities, within these exposure time-frames. Various reasons are discussed in an attempt to explain these findings. PMID:25208000
Noh, Jin-Won; Park, Hyunchun; Kim, Minji; Kwon, Young Dae; Kim, Jin-Seok
2018-01-01
Objective This study investigated the mediation effect of stress between the experience of discrimination and life satisfaction among North Korean refugees who resettled in South Korea. The findings of the current study provide empirical evidence for the need of social interventions to mitigate adverse effects of stress on North Korean refugees who are subject to social discrimination on a daily basis. Methods In this study, we included 500 subjects among 2,138 North Korean refugees who took refuge in South Korea in 2007. The interview started from April 6th 2009 and finished on May 25th 2009. We conducted moderator effect analysis with Path analysis was conducted because we confirm the experience of discrimination was affected by life satisfaction and stress can affected life satisfaction as a moderator. Results The experience of discrimination significantly affects stress and stress significantly affects life satisfaction. However, the experience of discrimination was not directly related to life satisfaction. The more stress the study respondents experienced, the lower the life satisfaction they reported. Conclusion The present finding suggests that the effects of discriminating experiences on the life satisfaction of North Korean refugees in South Korea were mediated by their own perceived stress. PMID:29422925
"I am just thankful": the experience of gratitude following traumatic spinal cord injury.
Chun, Sanghee; Lee, Youngkhill
2013-01-01
This study explored the experience of gratitude in everyday life following traumatic spinal cord injury (SCI) by applying thematic analysis to personal experience narratives. Fifteen participants including two negative cases with SCI shared individual experiences of gratitude according to five themes: (a) everyday life, (b) family support, (c) new opportunities, (d) positive sense of self, and (e) gratitude to God. The findings demonstrated that participants benefited from their efforts to appraise challenging life experiences as positive. Therapists could apply intentional and guided gratitude interventions so that individuals would practice and embrace gratitude in adjusting, coping, and adapting positively to various life changes following trauma.
Störmer, Charlotte; Lummaa, Virpi
2014-01-01
Life History Theory predicts that extrinsic mortality risk is one of the most important factors shaping (human) life histories. Evidence from contemporary populations suggests that individuals confronted with high mortality environments show characteristic traits of fast life-history strategies: they marry and reproduce earlier, have shorter birth intervals and invest less in their offspring. However, little is known of the impact of mortality experiences on the speed of life histories in historical human populations with generally higher mortality risk, and on male life histories in particular. Furthermore, it remains unknown whether individual-level mortality experiences within the family have a greater effect on life-history decisions or family membership explains life-history variation. In a comparative approach using event history analyses, we study the impact of family versus individual-level effects of mortality exposure on two central life-history parameters, ages at first marriage and first birth, in three historical human populations (Germany, Finland, Canada). Mortality experience is measured as the confrontation with sibling deaths within the natal family up to an individual's age of 15. Results show that the speed of life histories is not adjusted according to individual-level mortality experiences but is due to family-level effects. The general finding of lower ages at marriage/reproduction after exposure to higher mortality in the family holds for both females and males. This study provides evidence for the importance of the family environment for reproductive timing while individual-level mortality experiences seem to play only a minor role in reproductive life history decisions in humans. PMID:24421897
Störmer, Charlotte; Lummaa, Virpi
2014-01-01
Life History Theory predicts that extrinsic mortality risk is one of the most important factors shaping (human) life histories. Evidence from contemporary populations suggests that individuals confronted with high mortality environments show characteristic traits of fast life-history strategies: they marry and reproduce earlier, have shorter birth intervals and invest less in their offspring. However, little is known of the impact of mortality experiences on the speed of life histories in historical human populations with generally higher mortality risk, and on male life histories in particular. Furthermore, it remains unknown whether individual-level mortality experiences within the family have a greater effect on life-history decisions or family membership explains life-history variation. In a comparative approach using event history analyses, we study the impact of family versus individual-level effects of mortality exposure on two central life-history parameters, ages at first marriage and first birth, in three historical human populations (Germany, Finland, Canada). Mortality experience is measured as the confrontation with sibling deaths within the natal family up to an individual's age of 15. Results show that the speed of life histories is not adjusted according to individual-level mortality experiences but is due to family-level effects. The general finding of lower ages at marriage/reproduction after exposure to higher mortality in the family holds for both females and males. This study provides evidence for the importance of the family environment for reproductive timing while individual-level mortality experiences seem to play only a minor role in reproductive life history decisions in humans.
Crawford, Ronald L; Paszczynski, Andrzej; Lang, Qingyong; Erwin, Daniel P; Allenbach, Lisa; Corti, Giancarlo; Anderson, Tony J; Cheng, I Francis; Wai, Chien; Barnes, Bruce; Wells, Richard; Assefi, Touraj; Mojarradi, Mohammad
2002-01-01
Background Detecting microbial life in extraterrestrial locations is a goal of space exploration because of ecological and health concerns about possible contamination of other planets with earthly organisms, and vice versa. Previously we suggested a method for life detection based on the fact that living entities require a continual input of energy accessed through coupled oxidations and reductions (an electron transport chain). We demonstrated using earthly soils that the identification of extracted components of electron transport chains is useful for remote detection of a chemical signature of life. The instrument package developed used supercritical carbon dioxide for soil extraction, followed by chromatography or electrophoresis to separate extracted compounds, with final detection by voltammetry and tandem mass-spectrometry. Results Here we used Earth-derived soils to develop a related life detection system based on direct observation of a biological redox signature. We measured the ability of soil microbial communities to reduce artificial electron acceptors. Living organisms in pure culture and those naturally found in soil were shown to reduce 2,3-dichlorophenol indophenol (DCIP) and the tetrazolium dye 2,3-bis(2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide inner salt (XTT). Uninoculated or sterilized controls did not reduce the dyes. A soil from Antarctica that was determined by chemical signature and DNA analysis to be sterile also did not reduce the dyes. Conclusion Observation of dye reduction, supplemented with extraction and identification of only a few specific signature redox-active biochemicals such as porphyrins or quinones, provides a simplified means to detect a signature of life in the soils of other planets or their moons. PMID:12150716
Palareti, Laura; Potì, Silvia; Cassis, Frederica; Emiliani, Francesca; Matino, Davide; Iorio, Alfonso
2015-01-01
The study illuminates the subjective experience of haemophilia in people who took part in the Haemophilia Experience, Results and Opportunities (HERO) initiative, a quali-quantitative research program aimed at exploring psychosocial issues concerning this illness around the world. Applying a bottom-up analytic process with the help of software for textual data, we investigated 19 interviews in order to describe the core themes and the latent factors of speech, to explore the role of different variables in shaping the participants’ illness experiences. The five themes detected are feeling different from others, body pain, acquisition of knowledge and resources, family history, and integration of care practices in everyday life. We illustrate how nationality, age, family situation, the use of prophylaxis or on-demand treatment, and the presence of human immunodeficiency virus or hepatitis C virus affect the experience of our participants in different ways. Findings are used to bring insights on research, clinical practice, and psychosocial support. PMID:26578360
Seeking the Tricorder: Report on Workshops on Advanced Technologies for Life Detection
NASA Astrophysics Data System (ADS)
Reiss-Bubenheim, D.; Boston, P. J.; Partridge, H.; Lindensmith, C.; Nadeau, J. L.
2017-12-01
There's great excitement about life prospects on icy fluid-containing moons orbiting our Solar System's gas giant planets, newly discovered planet candidates and continuing long-term interest in possible Mars life. The astrobiology/planetary research communities require advanced technologies to explore and study both Solar System bodies and exoplanets for evidence of life. The Tricorder Workshop, held at Ames Research Center May 19-20, 2017, explored technology topics focused on non-invasive or minimally invasive methods for life detection. The workshop goal was to tease out promising ideas for low TRL concepts for advanced life detection technologies that could be applied to the surface and near-subsurface of Mars and Ocean Worlds (such as Europa and Enceladus) dominated by icy terrain. The workshop technology focus centered on mid-to-far term instrument concepts or other enabling technologies (e.g. robotics, machine learning, etc.) primarily for landed missions, which could detect evidence of extant, extinct and/or "weird" life including the notion of "universal biosignatures". Emphasis was placed on simultaneous and serial sample measurements using a suite of instruments and technological approaches with planetary protection in mind. A follow-on workshop, held July 24 at Caltech, sought to develop a generic flowchart of in situ observations and measurements to provide sufficient information to determine if extant life is present in an environment. The process didn't require participant agreement as to definition of extant life, but instead developed agreement on necessary observations and instruments. The flowchart of measurements was designed to maximize the number of simultaneous observations on a single sample where possible, serializing where necessary, and finally dividing it into parts for the most destructive analyses at the end. Selected concepts from the workshops outlined in this poster provide those technology areas necessary to solicit and develop for future life detection exploration via fly-by missions, orbiters, and landers.
Opaas, Marianne; Varvin, Sverre
2015-09-01
Adverse and potentially traumatic experiences (PTEs) in childhood were examined among 54 adult refugee patients with pre-flight PTEs of war and human rights violations (HRVs) and related to mental health and quality of life at treatment start. Extent of childhood PTEs was more strongly related to mental health and quality of life than the extent of war and HRV experiences. Childhood PTEs were significantly related to arousal and avoidance symptoms of posttraumatic stress disorder (PTSD) and to quality of life, whereas pre-flight war and HRV experiences were significantly related to reexperiencing symptoms of PTSD only. Within childhood adversities, experiences of family violence and external violence, but not of loss and illness, were significantly related to increased mental health symptoms and reduced quality of life. These results point to the importance of taking childhood adverse experiences into account in research and treatment planning for adult refugees with war and HRVs trauma.
Solonin, Iu G; Markov, A L; Boĭko, E R; Potolitsyna, N N; Parshukova, O I
2014-01-01
17 male northerners participating in the satellite experiments of the '"Mars-500" project passed through the morphological, physiometric, psychological and biochemical studies. The prenosological health indices in different seasons were calculated using the hardware-software complex "Ecosan-2007". Seasonal sinusoidal fluctuations were detected for the thermoregulation (body and skin temperature), lipids metabolism (cholesterol, HDL and LDL levels in the blood), circulation regulation under physical exercise (the increase of "double product" and its recovery time). In the majority of the participants the unfavorable deviations of body mass index, "power" and "life" indices, simple visual-motor reaction time, Kerdo vegetative index, physical health levels and regulatory systems activity index (in comparison with the mid-latitude standards) were found.
Damage Assessment of Creep Tested and Thermally Aged Metallic Alloys Using Acousto-Ultrasonics
NASA Technical Reports Server (NTRS)
Gyekenyesi, Andrew L.; Kautz, Harold E.; Baaklini, George Y.
2001-01-01
In recent years emphasis has been placed on the early detection of material changes experienced in turbine powerplant components. During the scheduled overhaul of a turbine, the current techniques of examination of various hot section components aim to find flaws such as cracks, wear, and erosion, as well as excessive deformations. Thus far, these localized damage modes have been detected with satisfactory results. However, the techniques used to find these flaws provide no information on life until the flaws are actually detected. Major improvements in damage assessment, safety, as well as more accurate life prediction could be achieved if nondestructive evaluation (NDE) techniques could be utilized to sense material changes that occur prior to the localized defects mentioned. Because of elevated temperatures and excessive stresses, turbine components may experience creep behavior. As a result, it is desirable to monitor and access the current condition of such components. Research at the NASA Glenn Research Center involves developing and utilizing an NDE technique that discloses distributed material changes that occur prior to the localized damage detected by the current methods of inspection. In a recent study, creep processes in a nickel-base alloy were the life-limiting condition of interest, and the NDE technique was acousto-ultrasonics (AU). AU is an NDE technique that utilizes two ultrasonic transducers to interrogate the condition of a test specimen. The sending transducer introduces an ultrasonic pulse at a point on the surface of the specimen while a receiving transducer detects the signal after it has passed through the material. The goal of the method is to correlate certain parameters of the detected waveform to characteristics of the material between the two transducers. Here, the waveform parameter of interest is the attenuation due to internal damping for which information is being garnered from the frequency domain. The parameters utilized to indirectly quantify the attenuation are the ultrasonic decay rate as well as various moments of the frequency power spectrum. A new, user-friendly, graphical interface AU system was developed at NASA Glenn. This system is an all-inclusive, multifunction system that controls the sending and receiving ultrasonic transducers as well as all posttest signal analysis. The system's postprocessing software calculates the multiple parameters used to study the material of interest.
Structural health management of aerospace hotspots under fatigue loading
NASA Astrophysics Data System (ADS)
Soni, Sunilkumar
Sustainability and life-cycle assessments of aerospace systems, such as aircraft structures and propulsion systems, represent growing challenges in engineering. Hence, there has been an increasing demand in using structural health monitoring (SHM) techniques for continuous monitoring of these systems in an effort to improve safety and reduce maintenance costs. The current research is part of an ongoing multidisciplinary effort to develop a robust SHM framework resulting in improved models for damage-state awareness and life prediction, and enhancing capability of future aircraft systems. Lug joints, a typical structural hotspot, were chosen as the test article for the current study. The thesis focuses on integrated SHM techniques for damage detection and characterization in lug joints. Piezoelectric wafer sensors (PZTs) are used to generate guided Lamb waves as they can be easily used for onboard applications. Sensor placement in certain regions of a structural component is not feasible due to the inaccessibility of the area to be monitored. Therefore, a virtual sensing concept is introduced to acquire sensor data from finite element (FE) models. A full three dimensional FE analysis of lug joints with piezoelectric transducers, accounting for piezoelectrical-mechanical coupling, was performed in Abaqus and the sensor signals were simulated. These modeled sensors are called virtual sensors. A combination of real data from PZTs and virtual sensing data from FE analysis is used to monitor and detect fatigue damage in aluminum lug joints. Experiments were conducted on lug joints under fatigue loads and sensor signals collected were used to validate the simulated sensor response. An optimal sensor placement methodology for lug joints is developed based on a detection theory framework to maximize the detection rate and minimize the false alarm rate. The placement technique is such that the sensor features can be directly correlated to damage. The technique accounts for a number of factors, such as actuation frequency and strength, minimum damage size, damage detection scheme, material damping, signal to noise ratio and sensing radius. Advanced information processing methodologies are discussed for damage diagnosis. A new, instantaneous approach for damage detection, localization and quantification is proposed for applications to practical problems associated with changes in reference states under different environmental and operational conditions. Such an approach improves feature extraction for state awareness, resulting in robust life prediction capabilities.
Pasternack, Camilla; Kaukinen, Katri; Kurppa, Kalle; Mäki, Markku; Collin, Pekka; Reunala, Timo; Huhtala, Heini; Salmi, Teea
2015-12-01
Dermatitis herpetiformis (DH) is a cutaneous manifestation of celiac disease. Both conditions are treated with a restrictive life-long gluten-free diet (GFD). Treated celiac disease patients have been shown to have more severe gastrointestinal symptoms and inferior quality of life compared with healthy controls, but evidence regarding quality of life in DH is lacking. The aim was to evaluate whether long-term GFD-treated DH patients suffer from persistent gastrointestinal symptoms and if they experience a drawdown in quality of life. Gastrointestinal symptoms and quality of life were assessed in 78 long-term GFD-treated DH patients using the validated Gastrointestinal Symptom Rating Scale, Psychological General Well-Being and Short Form 36 Health Survey questionnaires. The findings were compared with 110 healthy controls, population-based reference values and 371 treated celiac disease controls. The median age of the DH patients at the time of the study was 57 years, and 51 % were male. Significant differences in gastrointestinal symptoms or quality of life were not detected when treated DH patients were compared with healthy controls, but treated DH patients had less severe gastrointestinal symptoms and increased quality of life compared with celiac disease controls. Female DH patients had more severe gastrointestinal symptoms and reduced vitality compared with male DH patients. The presence of skin symptoms and the adherence to or duration of GFD did not have any influence on gastrointestinal symptoms or quality of life. We conclude that long-term GFD-treated DH patients do not suffer from the burden of dietary treatment and have a quality of life comparable to that of controls.
Experimental control requirements for life sciences
NASA Technical Reports Server (NTRS)
Berry, W. E.; Sharp, J. C.
1978-01-01
The Life Sciences dedicated Spacelab will enable scientists to test hypotheses in various disciplines. Building upon experience gained in mission simulations, orbital flight test experiments, and the first three Spacelab missions, NASA will be able to progressively develop the engineering and management capabilities necessary for the first Life Sciences Spacelab. Development of experiments for these missions will require implementation of life-support systems not previously flown in space. Plant growth chambers, animal holding facilities, aquatic specimen life-support systems, and centrifuge-mounted specimen holding units are examples of systems currently being designed and fabricated for flight.
Comparison of Antemortem and Environmental Samples for Zebrafish Health Monitoring and Quarantine.
Crim, Marcus J; Lawrence, Christian; Livingston, Robert S; Rakitin, Andrei; Hurley, Shane J; Riley, Lela K
2017-07-01
Molecular diagnostic assays offer both exquisite sensitivity and the ability to test a wide variety of sample types. Various types of environmental sample, such as detritus and concentrated water, might provide a useful adjunct to sentinels in routine zebrafish health monitoring. Similarly, antemortem sampling would be advantageous for expediting zebrafish quarantine, without euthanasia of valuable fish. We evaluated the detection of Mycobacterium chelonae, M. fortuitum, M. peregrinum, Pseudocapillaria tomentosa, and Pseudoloma neurophilia in zebrafish, detritus, pooled feces, and filter membranes after filtration of 1000-, 500-, and 150-mL water samples by real-time PCR analysis. Sensitivity varied according to sample type and pathogen, and environmental sampling was significantly more sensitive than zebrafish sampling for detecting Mycobacterium spp. but not for Pseudocapillaria neurophilia or Pseudoloma tomentosa. The results of these experiments provide strong evidence of the utility of multiple sample types for detecting pathogens according to each pathogen's life cycle and ecological niche within zebrafish systems. In a separate experiment, zebrafish subclinically infected with M. chelonae, M. marinum, Pleistophora hyphessobryconis, Pseudocapillaria tomentosa, or Pseudoloma neurophilia were pair-spawned and individually tested with subsets of embryos from each clutch that received no rinse, a fluidizing rinse, or were surface-disinfected with sodium hypochlorite. Frequently, one or both parents were subclinically infected with pathogen(s) that were not detected in any embryo subset. Therefore, negative results from embryo samples may not reflect the health status of the parent zebrafish.
Comparison of Antemortem and Environmental Samples for Zebrafish Health Monitoring and Quarantine
Crim, Marcus J; Lawrence, Christian; Livingston, Robert S; Rakitin, Andrei; Hurley, Shane J; Riley, Lela K
2017-01-01
Molecular diagnostic assays offer both exquisite sensitivity and the ability to test a wide variety of sample types. Various types of environmental sample, such as detritus and concentrated water, might provide a useful adjunct to sentinels in routine zebrafish health monitoring. Similarly, antemortem sampling would be advantageous for expediting zebrafish quarantine, without euthanasia of valuable fish. We evaluated the detection of Mycobacterium chelonae, M. fortuitum, M. peregrinum, Pseudocapillaria tomentosa, and Pseudoloma neurophilia in zebrafish, detritus, pooled feces, and filter membranes after filtration of 1000-, 500-, and 150-mL water samples by real-time PCR analysis. Sensitivity varied according to sample type and pathogen, and environmental sampling was significantly more sensitive than zebrafish sampling for detecting Mycobacterium spp. but not for Pseudocapillaria neurophilia or Pseudoloma tomentosa. The results of these experiments provide strong evidence of the utility of multiple sample types for detecting pathogens according to each pathogen's life cycle and ecological niche within zebrafish systems. In a separate experiment, zebrafish subclinically infected with M. chelonae, M. marinum, Pleistophora hyphessobryconis, Pseudocapillaria tomentosa, or Pseudoloma neurophilia were pair-spawned and individually tested with subsets of embryos from each clutch that received no rinse, a fluidizing rinse, or were surface-disinfected with sodium hypochlorite. Frequently, one or both parents were subclinically infected with pathogen(s) that were not detected in any embryo subset. Therefore, negative results from embryo samples may not reflect the health status of the parent zebrafish. PMID:28724491
Biological Contamination of Mars: Issues and Recommendations
NASA Technical Reports Server (NTRS)
1992-01-01
The ad hoc Task Group on Planetary Protection formed by the Space Studies Board (SSB) of the National Research Council focused on making recommendations concerning the protection of Mars from forward contamination (i.e., Earth to Mars) during upcoming missions by both the United States and the former Soviet Union. In so doing, it distinguished between missions whose goals include reconnaissance and measurement and those that specifically include experiments to detect life. The task group also discussed what additional knowledge will be needed in order to assure that future recommendations regarding contamination of Earth from Mars might be made with a higher degree of certainty than is now possible. Following a short introduction to the rationale underlying planetary exploration (Chapter 1) is a brief summary of approved and contemplated missions to Mars (Chapter 2). Chapter 3 briefly reviews the state of knowledge in several areas pertinent to the problem of planetary protection, in the limits of life on Earth and the abilities of known terrestrial organisms to withstand extreme environment conditions, as well as new approaches to detecting life forms. Chapter 5 includes a review and comments (made in light of current knowledge)- on the recommendations made in 'Recommendations on Quarantine Policy for Mars, Jupiter, Saturn, Uranus, Neptune, and Titan'. Updates to the recommendations made in 1978 are also given in Chapter 5. Chapter 6 gives additional recommendations concerning collection of essential data, spacecraft sterilization and bioburden assessment, and future research, as well as legal and social issues and NASA's overall planetary protection program.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Labatiuk, C.W.; Finch, G.R.; Belosevic, M.
1991-11-01
Giardia muris cyst viability after ozonation was compared by using fluorescein diacetate-ethidium bromide staining, the C3H/HeN mouse-G. muris model, and in vitro excystation. Bench-scale batch experiments were conducted under laboratory conditions (pH 6.7, 22C) in ozone-demand-free phosphate buffer. There was a significant difference between fluorogenic staining and infectivity with fluorogenic staining overestimating viability compared with infectivity estimates of viability. This suggests that viable cysts as indicated by fluorogenic dyes may not be able to complete the life cycle and produce an infection. No significant differences between infectivity and excystation and between fluorogenic staining and excystation were detected for inactivations upmore » to 99.9%. Only animal infectivity had the sensitivity to detect inactivations greater than 99.9%. Therefore, the animal model is the best method currently available for detecting high levels of G. muris cyst inactivation.« less
Kedrov, Alexej; Janovjak, Harald; Sapra, K Tanuj; Müller, Daniel J
2007-01-01
Molecular interactions are the basic language of biological processes. They establish the forces interacting between the building blocks of proteins and other macromolecules, thus determining their functional roles. Because molecular interactions trigger virtually every biological process, approaches to decipher their language are needed. Single-molecule force spectroscopy (SMFS) has been used to detect and characterize different types of molecular interactions that occur between and within native membrane proteins. The first experiments detected and localized molecular interactions that stabilized membrane proteins, including how these interactions were established during folding of alpha-helical secondary structure elements into the native protein and how they changed with oligomerization, temperature, and mutations. SMFS also enables investigators to detect and locate molecular interactions established during ligand and inhibitor binding. These exciting applications provide opportunities for studying the molecular forces of life. Further developments will elucidate the origins of molecular interactions encoded in their lifetimes, interaction ranges, interplay, and dynamics characteristic of biological systems.
Rice, Simon M; Fallon, Barry J; Aucote, Helen M; Möller-Leimkühler, AnneMaria; Treeby, Matt S; Amminger, G Paul
2015-05-01
Clinical reports indicate that men tend to engage in a range of externalising behaviours in response to negative emotional states. Such externalising behaviours have been theorised to reflect a male sub-type of depression that is inconsistent with current diagnostic criteria, resulting in impeded detection and treatment rates of depressed men. In addressing previous study design limitations, this article presents self-report longitudinal data for the multidimensional Male Depression Risk Scale (MDRS-22) against ratings of diagnostic criteria for major depressive disorder as assessed by the Patient Health Questionnaire-Depression Module (PHQ-9). Longitudinal psychometric properties of the MDRS-22 are reported and symptom trajectories described. A sample of 233 adults (males = 125; 54%) completed measures of externalising and prototypic depression symptoms at Time 1, and again at Time 2 (15 weeks later). Psychometric properties were examined and within-subjects analyses undertaken. The MDRS-22 demonstrated stable internal consistency and test-retest correlations equivalent to those observed for the PHQ-9. Both prototypic and externalising depression symptoms increased with experiences of recent negative life events. Marked gender differences were observed. Males experiencing ≥ 2 stressful negative life events reported significantly higher MDRS-22 scores at both Time 1 and Time 2 relative to comparable females. Findings contribute to the validity of the MDRS-22 as a measure of externalising depression symptoms. Results suggest that while both males and females experience externalising depression symptoms, these symptoms may be particularly elevated for men following experiences of negative life events. Findings suggest that externalising symptoms may be a special feature of depression for men. Given the problematic nature of such externalising symptoms (e.g. excessive substance use, aggression, risk-taking), their clinical assessment appears warranted. © The Author(s) 2014.
NASA Astrophysics Data System (ADS)
Wainwright, N. R.; Steele, A.; Monaco, L.; Fries, M.
2017-02-01
Life detection goals and technologies are remarkably similar between several types of NASA missions and the pharmaceutical and biotechnology industries. Needs for sensitivity, specificity, speed have driven techniques and equipment to common ends.
Panel Discussion: Life in the Cosmos
NASA Technical Reports Server (NTRS)
Hoover, Richard B.
2009-01-01
Water appears to be essential to all life on Earth. For this reason, "Follow the Water" has been adopted as a mantra for the search for Life in the Cosmos. Expeditions have helped to establish the limits and biodiversity of life in the most extreme environments on Earth. Microbial extremophiles inhabit acidic streams; hypersaline and hyperalkaline lakes and pools; the cold deep sea floor, permafrost, rocks, glaciers, and perennially ice-covered lakes of the polar environments; geysers, volcanic fumaroles, hydrothermal vents and hot rocks deep within the Earth's crust. The ESA Venus Express Spacecraft entered Venusian Orbit in 2006 and continues to produce exciting results. The Visible and Infrared Thermal Imaging Spectrometer (VIRTIS) instrument made the first detection of hydroxyl in the atmosphere of Venus, indicating it is much more similar to Earth and Mars than previously thought. Huge hurricane-like vortices have been found above the poles of the planet and as yet unidentified UV absorbers that form mysterious dark bands in the upper atmosphere. At 70 km and below, water vapor and sulfur dioxide combine to form sulfuric acid droplets that create a haze above the cloud tops. Thermophilic acidophiles, such as have recently been discovered on Earth, could possibly survive in the hot sulfuric acid droplets that exist in the upper atmosphere of Venus. In order to understand how to search for life elsewhere in the Solar System, over 40 VIRTIS images of Earth from Venus have been obtained to search for evidence of life on Earth. The signatures of water and molecular Oxygen were detected in the Earth s atmosphere, but the atmosphere of Venus also exhibits these signatures. The water and water ice are far more abundant on comet, the polar caps and permafrost of Mars and the icy moons of Jupiter and Saturn. These "frozen worlds" of our Solar System, are much more promising regimes where extant or extinct microbial life may exist. The ESA Mars Advanced Radar for Subsurface and Ionospheric Sounding (MARSIS) probe has found that both the North and South Polar Caps of Mars are approximately 3.5 km thick and are composed almost entirely of water ice. In winter, a thin dry ice layer covers the caps, but it sublimates directly to CO2 in the spring. The ESA Mars Express Orbiter images reveal Rupes Tenuis to be a vast snow-laden region on the southern edge of the Martian North Polar Cap. The Mars Exploration Rover Spirit found alkaline volcanic rocks in the Gusev Crater and the Phoenix Mars Lander has shown that the soil of Mars is much more alkaline than previously expected. The Phoenix Mars Lander has also made direct observations of frozen and liquid water on Mars. It is known that microorganisms from Alaska, Siberia and Antarctica can remain alive frozen in permafrost or ice for long periods of time. These discoveries increase the possibility that the Labeled Release Experiment may have discovered life on Mars during the Viking Mission and provide strong impetus for the return of life detection experiments to Mars. Changes in the spin rate of Saturn's moon Titan indicate that it may also harbor a 300 km thick liquid water ocean beneath its icy crust. The NASA/ESA/Italian Space Agency Cassini Spacecraft has imaged geysers containing water vapor, methane, carbon dioxide and organics erupting from the "tiger stripe" regions near the South Pole of Saturn's moon Enceladus. The high temperatures observed, the water vapor and large number of ice particles expelled suggest that a liquid water lake may exist beneath the "tiger stripe" ice cracks of Enceladus. The NASA Deep Impact probe found the surface temperature of comet 9P/Temple 1 at 1.5 AY was slightly above the ice/water phase change temperature (273 K). This suggests melting of water ice near the comet surface. A spectrometer the spacecraft detected a mixture of clay and carbonate minerals (that form in the presence of liquid water) streaming off the comet after the collision with the pactor. The study of chemical and mineral biomarkers, chiral amino acids and possible indigenous microfossils in SNC and carbonaceous meteorites continues. These results suggest that comets should be considered prime targets in the search for Life in the Cosmos. The ESA Rosetta mission is on track to rendezvous with comet 67P/Churyumov-Gerasimenko. The recent space observations combined with new information about the ability of microbial extremophiles to thrive in polar environments suggest that life may be far more widely distributed in the Cosmos than previously thought possible. The Panelists will review recent discoveries and provide their own insights about Life in the Cosmos -- followed by a question and answer session with the audience.
A Statistical Approach to Illustrate the Challenge of Astrobiology for Public Outreach.
Foucher, Frédéric; Hickman-Lewis, Keyron; Westall, Frances; Brack, André
2017-10-26
In this study, we attempt to illustrate the competition that constitutes the main challenge of astrobiology, namely the competition between the probability of extraterrestrial life and its detectability. To illustrate this fact, we propose a simple statistical approach based on our knowledge of the Universe and the Milky Way, the Solar System, and the evolution of life on Earth permitting us to obtain the order of magnitude of the distance between Earth and bodies inhabited by more or less evolved past or present life forms, and the consequences of this probability for the detection of associated biosignatures. We thus show that the probability of the existence of evolved extraterrestrial forms of life increases with distance from the Earth while, at the same time, the number of detectable biosignatures decreases due to technical and physical limitations. This approach allows us to easily explain to the general public why it is very improbable to detect a signal of extraterrestrial intelligence while it is justified to launch space probes dedicated to the search for microbial life in the Solar System.
A Statistical Approach to Illustrate the Challenge of Astrobiology for Public Outreach
Westall, Frances; Brack, André
2017-01-01
In this study, we attempt to illustrate the competition that constitutes the main challenge of astrobiology, namely the competition between the probability of extraterrestrial life and its detectability. To illustrate this fact, we propose a simple statistical approach based on our knowledge of the Universe and the Milky Way, the Solar System, and the evolution of life on Earth permitting us to obtain the order of magnitude of the distance between Earth and bodies inhabited by more or less evolved past or present life forms, and the consequences of this probability for the detection of associated biosignatures. We thus show that the probability of the existence of evolved extraterrestrial forms of life increases with distance from the Earth while, at the same time, the number of detectable biosignatures decreases due to technical and physical limitations. This approach allows us to easily explain to the general public why it is very improbable to detect a signal of extraterrestrial intelligence while it is justified to launch space probes dedicated to the search for microbial life in the Solar System. PMID:29072614
It's not going to be that fun: negative experiences can add meaning to life.
Vohs, Kathleen D; Aaker, Jennifer L; Catapano, Rhia
2018-04-22
People seek to spend time in positive experiences, enjoying and savoring. Yet there is no escaping negative experiences, from the mundane (e.g. arguing) to the massive (e.g. death of a child). Might negative experiences confer a hidden benefit to well-being? We propose that they do, in the form of enhanced meaning in life. Research suggests that negative experiences can serve to boost meaning because they stimulate comprehension (understanding how the event fits into a broader narrative of the self, relationships, and the world), a known pillar of meaning in life. Findings on counterfactual thinking, reflecting on events' implications, and encompassing experiences into broad-based accounts of one's identity support the role of comprehension in contributing to life's meaning from unwanted, unwelcome experiences. Copyright © 2018 Elsevier Ltd. All rights reserved.
[The daily experience of the patient with an implantable cardioverter defibrillator].
Palacios-Ceña, Domingo; Alonso-Blanco, Cristina; Cachón-Pérez, José Miguel; Alvarez-López, Cristina
2010-01-01
To describe the daily experience of patients with an automatic defibrillator (AD) implant and the adaptive changes of the patient. Qualitative and phenomenological research. Collection of data through; initially unstructured interview with half of the informants, semi-structured interviews through an open questions guide after the initial unstructured interviews and use of personal narratives of the informants. Analysis of the data using the Van Manen proposal. We analysed the interviews of 10 participants. We collected socio-demographic variables and identified the following themes, which respond to the question "How is life with an AD": It is life "with the two sides of the coin," living in constant wait and uncertainty, accepting change, developing adaptation strategies, renegotiating relationships and sexuality and it is to live transformed. The results of this study can be integrated into nurse clinical practice in areas such as valuation after discharge, changes in habits, control of treatment, notification of shocks, masking detection of symptoms and strategies that can jeopardise the bearer. Research needs to be developed that looks closer into the influence of other technological devices in people. Copyright 2009 Elsevier España, S.L. All rights reserved.
Chiral Determination of Amino Acids Using X-Ray Diffraction of Thin Films
NASA Technical Reports Server (NTRS)
Dragoi, D.; Kulleck, J.; Kanik, I.; Beegle, L. W.
2003-01-01
The astrobiological search for life, both extinct and extant, on other solar system bodies will take place via several planned lander missions to Mars Europa and Titan. The detection and identification of organic molecules that have been associated with life is a major technical challenge. Terrestrial life utilizes organic molecules, such as amino acids, as its basic building block. Amino acids can be synthesized by natural processes as is demonstrated by their detection in meteoritic material. In this process, the organic molecules are produced roughly in a even mixture of D and L forms. Biological process, however, can utilize almost uniquely one form or the other. In terrestrial biology, only the L-amino acids is common in biological processes. If signature of life existed elsewhere in the D form it then be concluded that life had evolutionary beginning on that body. Detection of an enantiomeric excess of L over D would also be a powerful sign that life had existed on that body at one time.
Facing page test for the astronaut science advisor presentation
NASA Technical Reports Server (NTRS)
Compton, Michael M.
1991-01-01
The goal of the Astronaut Science Advisor (ASA) project is to improve the scientific return of experiments performed in space by providing astronaut experimenters with an 'intelligent assistant' that encapsulates much of the domain- and experiment-related knowledge commanded by the Principal Investigator (PI) on the ground. By using expert systems technology and the availability of flight-qualified personal computers, it is possible to encode the requisite knowledge and make it available to astronauts as they perform experiments in space. The system performs four major functions: diagnosis and troubleshooting of experiment apparatus, data collection, protocol management, and detection of interesting data. The experiment used for development of the system measures human adaptation to weightlessness in the context of the neurovestibular system. This so-called 'Rotating Dome' experiment was flown on the recent Spacelab Life Sciences One (SLS-1) Mission. This mission was used as an opportunity to test some of the system's functionality. Experiment data was downlinked from the orbiter, and the system then captured the data and analyzed it in real time. The system kept track of the time being used by the experiment, recognized occurrences of interesting data, summarized data statistically and generated potential new protocols that could be used to optimize the course of the experiment.
Climatic niche and flowering and fruiting phenology of an epiphytic plant.
Barve, Narayani; Martin, Craig E; Peterson, A Townsend
2015-09-10
Species have geographic distributions constrained by combinations of abiotic factors, biotic factors and dispersal-related factors. Abiotic requirements vary across the life stages for a species; for plant species, a particularly important life stage is when the plant flowers and develops seeds. A previous year-long experiment showed that ambient temperature of 5-35 °C, relative humidity of >50 % and ≤15 consecutive rainless days are crucial abiotic conditions for Spanish moss (Tillandsia usneoides L.). Here, we explore whether these optimal physiological intervals relate to the timing of the flowering and fruiting periods of Spanish moss across its range. As Spanish moss has a broad geographic range, we examined herbarium specimens to detect and characterize flowering/fruiting periods for the species across the Americas; we used high-temporal-resolution climatic data to assess the availability of optimal conditions for Spanish moss populations during each population's flowering period. We explored how long populations experience suboptimal conditions and found that most populations experience suboptimal conditions in at least one environmental dimension. Flowering and fruiting periods of Spanish moss populations are either being optimized for one or a few parameters or may be adjusted such that all parameters are suboptimal. Spanish moss populations appear to be constrained most closely by minimum temperature during this period. Published by Oxford University Press on behalf of the Annals of Botany Company.
Ninth Graders' Learning Interests, Life Experiences and Attitudes Towards Science & Technology
NASA Astrophysics Data System (ADS)
Chang, Shu-Nu; Yeung, Yau-Yuen; Cheng, May Hung
2009-10-01
Students' learning interests and attitudes toward science have both been studied for decades. However, the connection between them with students' life experiences about science and technology has not been addressed much. The purpose of this study is to investigate students' learning interests and life experiences about science and technology, and also their attitudes toward technology. A total of 942 urban ninth graders in Taiwan were invited to participate in this study. A Likert scale questionnaire, which was developed from an international project, ROSE, was adapted to collect students' ideas. The results indicated that boys showed higher learning interests in sustainability issues and scientific topics than girls. However, girls recalled more life experiences about science and technology in life than boys. The data also presented high values of Pearson correlation about learning interests and life experiences related to science and technology, and in the perspective on attitudes towards technology. Ways to promote girls' learning interests about science and technology and the implications of teaching and research are discussed as well.
NASA Technical Reports Server (NTRS)
Mitz, M. A.
1972-01-01
Some promising newer approaches for detecting microorganisms are discussed, giving particular attention to the integration of different methods into a single instrument. Life detection methods may be divided into biological, chemical, and cytological methods. Biological methods are based on the biological properties of assimilation, metabolism, and growth. Devices for the detection of organic materials are considered, taking into account an instrument which volatilizes, separates, and analyzes a sample sequentially. Other instrumental systems described make use of a microscope and the cytochemical staining principle.
Sigurvinsdottir, Rannveig; Asgeirsdottir, Bryndis Bjork; Ullman, Sarah E; Sigfusdottir, Inga Dora
2017-10-01
Stressful life experiences, such as sexual abuse and family violence/conflict, relate to an increased risk of mental health problems. Religion and spirituality may prevent this negative impact, but religion and spirituality are lower among survivors of stressful life experiences. To explore this effect, we examined the relationship between childhood sexual abuse and family violence/conflict on anger and depressed mood. Survey data were collected from a large population-based sample of Icelandic adolescents ( N = 7,365) on their stressful life experiences, religion, spirituality, and mental health. Survivors of stressful life experiences (sexual abuse or family violence/conflict) were significantly lower on religion and spirituality than others. A hierarchical linear regression showed that stressful life experiences contributed uniquely to higher levels of anger and depressed mood. Spirituality was associated with decreased anger and depressed mood. The religion of parents and peers was also associated with decreased anger. Religious participation, on the contrary, did not have a relationship with mental health outcomes. In addition, the negative association between spirituality and anger was stronger among survivors of sexual abuse than nonabused individuals. These results confirm previous research, indicating that survivors of stressful life experiences may experience less religion and spirituality. The results also extend existing knowledge by showing that spirituality may be even more beneficial among sexual abuse survivors, as a protective factor against anger. These findings can help in the minimization of the negative mental health impact of stressful life experiences.
NASA Astrophysics Data System (ADS)
Parro, V.; Rivas, L. A.; Rodríguez-Manfredi, J. A.; Blanco, Y.; de Diego-Castilla, G.; Cruz-Gil, P.; Moreno-Paz, M.; García-Villadangos, M.; Compostizo, C.; Herrero, P. L.
2009-04-01
Immunosensors have been extensively used since many years for environmental monitoring. Different technological platforms allow new biosensor designs and implementations. We have reported (Rivas et al., 2008) a shotgun approach for antibody production for biomarker detection in astrobiology and environmental monitoring, the production of 150 new polyclonal antibodies against microbial strains and environmental extracts, and the construction and validation of an antibody microarray (LDCHIP200, for "Life Detector Chip") containing 200 different antibodies. We have successfully used the LDCHIP200 for the detection of biological polymers in extreme environments in different parts of the world (e.g., a deep South African mine, Antarctica's Dry valleys, Yellowstone, Iceland, and Rio Tinto). Clustering analysis associated similar immunopatterns to samples from apparently very different environments, indicating that they indeed share similar universal biomarkers. A redundancy in the number of antibodies against different target biomarkers apart of revealing the presence of certain biomolecules, it renders a sample-specific immuno-profile, an "immnuno-fingerprint", which may constitute by itself an indirect biosignature. We will present a case study of immunoprofiling different iron-sulfur as well as phylosilicates rich samples along the Rio Tinto river banks. Based on protein microarray technology, we designed and built the concept instrument called SOLID (for "Signs Of LIfe Detector"; Parro et al., 2005; 2008a, b; http://cab.inta.es/solid) for automatic in situ analysis of soil samples and molecular biomarkers detection. A field prototype, SOLID2, was successfully tested for the analysis of grinded core samples during the 2005 "MARTE" campaign of a Mars drilling simulation experiment by a sandwich microarray immunoassay (Parro et al., 2008b). We will show the new version of the instrument (SOLID3) which is able to perform both sandwich and competitive immunoassays. SOLID3 consists of two separate functional units: a Sample Preparation Unit (SPU), for ten different extractions by ultrasonication, and a Sample Analysis Unit (SAU), for fluorescent immunoassays. The SAU consists of ten different flow cells each of one allocate one antibody microarray (up to 2000 spots), and is equipped with an unique designed optical package for fluorescent detection. We demonstrate the performance of SOLID3 for the detection of a broad range of molecular size compounds, from the amino acid size, peptides, proteins, to whole cells and spores, with sensitivities at the ppb level. References Parro, V., et al., 2005. Planetary and Space Science 53: 729-737. Parro, V., et al., 2008a. Space Science Reviews 135: 293-311 Parro, V., et al., 2008b. Astrobiology 8:987-99 Rivas, L. A., et al., 2008. Analytical Chemistry 80: 7970-7979
Understanding Latina/o Students' Meaning in Life, Spirituality, and Subjective Happiness
ERIC Educational Resources Information Center
Cavazos Vela, Javier; Castro, Veronica; Cavazos, Leticia; Cavazos, Michelle; Gonzalez, Stacey Lee
2015-01-01
One-hundred nineteen Latina/o college students provided perceptions of presence of meaning in life, search for meaning in life, daily spiritual experiences, and subjective happiness. Perceptions of meaning in life and daily spiritual experiences were significant predictors of subjective happiness. A discussion regarding the importance of these…
Betts, Kim S; Williams, Gail M; Najman, Jakob M; Scott, James; Alati, Rosa
2014-12-01
Exposure to stressful life events during pregnancy has been associated with later schizophrenia in offspring. We explore how prenatal stress and neurodevelopmental abnormalities in childhood associate to increase the risk of later psychotic experiences. Participants from the Mater University Study of Pregnancy (MUSP), an Australian based, pre-birth cohort study were examined for lifetime DSM-IV positive psychotic experiences at 21 years by a semi-structured interview (n = 2227). Structural equation modelling suggested psychotic experiences were best represented with a bifactor model including a general psychosis factor and two group factors. We tested for an association between prenatal stressful life events with the psychotic experiences, and examined for potential moderation and mediation by behaviour problems and cognitive ability in childhood. Prenatal stressful life events predicted psychotic experiences indirectly via behaviour problems at child age five years, and this relationship was not confounded by maternal stressful life events at child age five. We found no statistical evidence for an interaction between prenatal stressful life events and behaviour problems or cognitive ability. The measurable effect of prenatal stressful life events on later psychotic experiences in offspring manifested as behaviour problems by age 5. By identifying early abnormal behavioural development as an intermediary, this finding further confirms the role of prenatal stress to later psychotic disorders. Copyright © 2014 Elsevier Ltd. All rights reserved.
Forty to fifty-five-year-old women and iron deficiency: clinical considerations and quality of life.
Firquet, Anne; Kirschner, Wolf; Bitzer, Johannes
2017-07-01
Between the age of 40 and 55 years, women experience important changes in their lives. This period, which corresponds to the perimenopause for most women, is associated with the risk of iron deficiency anemia (IDA). The clinical presentation of anemia can be misleading, and the underlying cause, particularly bleeding, is frequently treated without concomitant iron prescription. Iron deficiency (ID) remains a social and economic burden in European countries. Underdiagnosed and undertreated, this problem has a strong negative impact on women's quality of life. The risk factors for ID are well known. The physician's role is essential in recognizing the symptoms, identifying the risk factors, detecting IDA by testing hemoglobin, and evaluating the degree of ID by measuring serum ferritin (SF). Iron therapy treats the anemia and restores iron stores, thus decreasing symptoms such as fatigue and restoring quality of life. Among the available forms of iron, evidence is in favor of ferrous sulfate in a slow release formulation, which is well-tolerated and results in good adherence, a key factor for efficacious supplementation.
SETI - The search for extraterrestrial intelligence - Plans and rationale
NASA Technical Reports Server (NTRS)
Wolfe, J. H.; Billingham, J.; Edelson, R. E.; Crow, R. B.; Gulkis, S.; Olsen, E. T.; Oliver, B. M.; Peterson, A. M.
1981-01-01
The methodology and instrumentation of a 10 yr search for extraterrestrial intelligence (SETI) program by NASA, comprising 5 yr for instrumentation development and 5 yr for observations, is described. A full sky survey in two polarizations between 1.2 and 10 GHz with resolution binwidths down to 32 Hz, and a two polarization can between 1.2-3 GHz with resolution binwidths down to 1 Hz of 700 nearby solar type stars within 20 light years of earth will extend the sensitivity of previous surveys by 300 times and cover 20,000 times more frequency space. EM signals are perceived as the only means for detecting life outside the solar system, and the SETI effort is driven by the empirical experience that once a physical process has been observed to occur, its occurrence elsewhere is assured. Further discussion is given of the history of searches for life in the Universe, the SETI search strategy, instrumentation, and signal identification.
Reconstructing Ancient Forms of Life
NASA Technical Reports Server (NTRS)
Benner, Steven A.
1998-01-01
Progress in the past three months has occurred in two areas, reconstruction of ancestral proteins and improved understanding of chemical features that are likely to be universal in generic matter regardless of its genesis. Ancestral ribonucleases have been reconstructed, and an example has been developed that shows how physiological function can be assigned to in vitro behaviors observed in biological systems. Sequence data have been collected to permit the reconstruction of src homology 2 domains that underwent radiative divergence at the time of the radiative divergence of chordates. New studies have been completed that show how genetic matter (or its remnants) might be detected on Mars (or other non-terrean locations.) Last, the first in vitro selection experiments have been completed using a nucleoside library carrying positively charged functionality, illustrating the importance of non-standard nucleotides to those attempting to obtain evidence for an "RNA world" as an early episode of life on earth.
Intelligent Rover Execution for Detecting Life in the Atacama Desert
NASA Technical Reports Server (NTRS)
Baskaran, Vijayakumar; Muscettola, Nicola; Rijsman, David; Plaunt, Chris; Fry, Chuck
2006-01-01
On-board supervisory execution is crucial for the deployment of more capable and autonomous remote explorers. Planetary science is considering robotic explorers operating for long periods of time without ground supervision while interacting with a changing and often hostile environment. Effective and robust operations require on-board supervisory control with a high level of awareness of the principles of functioning of the environment and of the numerous internal subsystems that need to be coordinated. We describe an on-board rover executive that was deployed on a rover as past of the "Limits of Life in the Atacama Desert (LITA)" field campaign sponsored by the NASA ASTEP program. The executive was built using the Intelligent Distributed Execution Architecture (IDEA), an execution framework that uses model-based and plan-based supervisory control of its fundamental computational paradigm. We present the results of the third field experiment conducted in the Atacama desert (Chile) in August - October 2005.
Understanding bladder management on a palliative care unit: a grounded theory study.
Gutmanis, Iris; Hay, Melissa; Shadd, Joshua; Byrne, Janette; McCallum, Sarah; Bishop, Kristen; Whitfield, Patricia; Faulds, Cathy
2017-03-16
Research regarding factors associated with nursing-initiated changes to bladder management at end-of-life is sparse. To explore the process of Palliative Care Unit (PCU) nurses' approach to bladder management changes. Nursing staff from one PCU in London, Canada were interviewed regarding bladder management care practices. A constructivist grounded theory was generated. Four interconnected themes emerged: humanity (compassionate support of patients); journey (making the most of a finite timeline); health condition (illness, functional decline); and context (orders, policies, supplies). These overlapping themes must be considered in light of ongoing changes which prompt recycling through the framework. While bladder management necessitates shared decision-making and individualised care, nurses' phronetic experience may serve to detect the presence of change and the need to consider other alternatives. End-of-life bladder management requires nurses to continually reconsider the significance of humanity, journey, health condition and context in light of ongoing changes.
The detection of extra-terrestrial life and the consequences for science and society.
Dominik, Martin; Zarnecki, John C
2011-02-13
Astronomers are now able to detect planets orbiting stars other than the Sun where life may exist, and living generations could see the signatures of extra-terrestrial life being detected. Should it turn out that we are not alone in the Universe, it will fundamentally affect how humanity understands itself--and we need to be prepared for the consequences. A Discussion Meeting held at the Royal Society in London, 6-9 Carlton House Terrace, on 25-26 January 2010, addressed not only the scientific but also the societal agenda, with presentations covering a large diversity of topics.
NASA Astrophysics Data System (ADS)
Vakoch, Douglas A.; Dowd, Matthew F.; Drake, Frank
2015-07-01
List of contributors; Foreword Frank Drake; Preface; Acknowledgements; Introduction Steven Dick; 1. Rate of formation of stars suitable for the development of intelligent life, R*, pre-1961 David DeVorkin; 2. Rate of formation of stars suitable for the development of intelligent life, R*, 1961 to the present Patrick François and Danielle Briot; 3. Fraction of stars with planetary systems, fp, pre-1961 Matthew F. Dowd; 4. Fraction of stars with planetary systems, fp, 1961 to the present Chris Impey; 5. Number of planets, per solar system, with an environment suitable for life, ne, pre-1961 Florence Raulin Cerceau; 6. Number of planets, per solar system, with an environment suitable for life, ne, 1961 to the present Danielle Briot and Jean Schneider; 7. Fraction of suitable planets on which life actually appears, fl, pre-1961 Stephané Tirard; 8. Fraction of suitable planets on which life actually appears, fl, 1961 to the present David J. Des Marais; 9. Fraction of life-bearing planets on which intelligent life emerges, fl, pre-1961 Michael Crowe; 10. Fraction of life-bearing planets on which intelligent life emerges, fl, 1961 to the present Lori Marino; 11. Fraction of civilizations that develop a technology that releases detectable signs of their existence into space, fc, pre-1961 Florence Raulin Cerceau; 12. Fraction of civilizations that develop a technology that releases detectable signs of their existence into space, fc, 1961 to the present Seth Shostak; 13. Length of time such civilizations release detectable signals into space, L, pre-1961 David Dunér; 14. Length of time such civilizations release detectable signals into space, L, 1961 to the present Garry Chick; Afterword Paul Davies; Index.
Detection of orthopaedic implants by airport metal detectors.
Abbassian, Ali; Datla, Balarama; Brooks, R A
2007-04-01
We performed a questionnaire study to establish the frequency and consequences of the detection of orthopaedic implants by airport security and to help us advise patients correctly. All published literature on this subject is based on experimental studies and no 'real-life' data are available. A total of 200 patients with a variety of implants were identified. All patients were sent a postal questionnaire enquiring about their experience with airport security since their surgery. Of the cohort, 154 (77%) patients responded. About half of the implants (47%) were detected, but the majority of patients (72%) were not significantly inconvenienced. When detected, only 9% of patients were asked for documentary evidence of their implant. We also found that patients with a total knee replacement (TKR) had a greater chance of detection as compared to those with a total hip replacement (THR; 71% versus 31%; P = 0.03). All patients, and in particular those with a TKR, can be re-assured that, although they have a fair chance of detection by airport security, a major disruption to their journey is unlikely. We advise that documentation to prove the presence of an orthopaedic implant should be offered to those who are concerned about the potential for inconvenience, but such documentation is not required routinely.
ERIC Educational Resources Information Center
Zurbriggen, Carmen L. A.; Venetz, Martin; Hinni, Chantal
2018-01-01
The aim of this paper is to investigate the quality of experience of students with and without SEN in everyday life in general and when relating to peers in particular: (1) How do they experience everyday school life vs. leisure time? (2) How much time per week do they spend with peers outside school? and (3) How do they experience those peer…
Detecting frail, older adults and identifying their strengths: results of a mixed-methods study.
Dury, Sarah; Dierckx, Eva; van der Vorst, Anne; Van der Elst, Michaël; Fret, Bram; Duppen, Daan; Hoeyberghs, Lieve; De Roeck, Ellen; Lambotte, Deborah; Smetcoren, An-Sofie; Schols, Jos; Kempen, Gertrudis; Zijlstra, G A Rixt; De Lepeleire, Jan; Schoenmakers, Birgitte; Verté, Dominique; De Witte, Nico; Kardol, Tinie; De Deyn, Peter Paul; Engelborghs, Sebastiaan; De Donder, Liesbeth
2018-01-30
The debate on frailty in later life focuses primarily on deficits and their associations with adverse (health) outcomes. In addition to deficits, it may also be important to consider the abilities and resources of older adults. This study was designed to gain insights into the lived experiences of frailty among older adults to determine which strengths can balance the deficits that affect frailty. Data from 121 potentially frail community-dwelling older adults in Flemish-speaking Region of Belgium and Brussels were collected using a mixed-methods approach. Quantitative data were collected using the Comprehensive Frailty Assessment Instrument (CFAI), Montreal Cognitive Assessment (MoCA), and numeric rating scales (NRS) for quality of life (QoL), care and support, meaning in life, and mastery. Bivariate analyses, paired samples t-tests and means were performed. Qualitative data on experiences of frailty, frailty balance, QoL, care and support, meaning in life, and mastery were collected using semi-structured interviews. Interviews were subjected to thematic content analysis. The "no to mild frailty" group had higher QoL, care and support, meaning in life, and mastery scores than the "severe frailty" group. Nevertheless, qualitative results indicate that, despite being classified as frail, many older adults experienced high levels of QoL, care and support, meaning in life, and mastery. Respondents mentioned multiple balancing factors for frailty, comprising individual-level circumstances (e.g., personality traits, coping strategies, resilience), environmental influences (e.g., caregivers, neighborhood, social participation), and macro-level features (e.g., health literacy, adequate financial compensation). Respondents also highlighted that life changes affected their frailty balance, including changes in health, finances, personal relationships, and living situation. The findings indicate that frailty among older individuals can be considered as a dynamic state and, regardless of frailty, balancing factors are important in maintaining a good QoL. The study investigated not only the deficits, but also the abilities, and resources of frail, older adults. Public policymakers and healthcare organizations are encouraged to include these abilities, supplementary or even complementary to the usual focus on deficits.
Children as Photographers: Life Experiences and the Right to Be Listened To
ERIC Educational Resources Information Center
Joubert, Ina
2012-01-01
This article is about an investigation of eight-year-old children's life experiences as child citizens in democratic South Africa, their right to be listened to and to participate in the democracy. Research indicates that understanding children's life experiences can influence adults' understanding of what needs to be done to support their…
Older Women and Sexuality: Experiences in Marital Relationships across the Life Course
ERIC Educational Resources Information Center
Clarke, Laura Hurd
2006-01-01
Rates of sexual activity have been found to decline over the life course, as individuals experience marital transitions and the loss of partners, health problems, and decreased sexual interest. This article compares and contrasts earlier and later-life sexual experiences and examines the changing meanings that older women ascribe to sexuality over…
ERIC Educational Resources Information Center
Miller, Byron
2012-01-01
The purpose of this qualitative study was to explore the life experiences and beliefs of high school teachers exhibiting highly effective classroom management skills. The research for this phenomenological study utilized the narrative inquiry method of data collection. This study investigates the life experiences and beliefs of nine teachers…
Wang, Bo; Li, Xiaoming; Stanton, Bonita; Fang, Xiaoyi
2010-07-01
The global literature has revealed a potential negative impact of social stigma on both physical and mental health among stigmatized individuals; however, the mechanisms through which social stigma affects the individual's quality of life and mental health are not well understood. This research simultaneously examines the relationships of several determinants and mediating factors of psychological distress and quality of life. Data were collected through a cross-sectional survey among 1006 adult (predominantly male) rural-to-urban migrants in 2004-2005 in Beijing, China. Participants reported on their perceived social stigma, discriminatory experiences in daily life, preparation for migration, discrepancy between expectation and reality, coping with stigma-related stress, psychological distress, and quality of life. Structural equation modeling was performed. We found that perceived social stigma and discriminatory experiences had direct negative effects on psychological distress and quality of life among rural-to-urban migrants. Expectation-reality discrepancy mediated the effects of perceived social stigma and discriminatory experiences on psychological distress and quality of life; coping mediated the effect of social stigma on quality of life. Psychological distress was associated with quality of life. Preparation prior to migration was positively related to coping skills, which were positively related to quality of life. We conclude that perceived social stigma and daily discriminatory experiences have a significant influence on psychological distress and quality of life among rural-to-urban migrants. Pre-migration training with a focus on establishment of effective coping skills and preparation of migration may be helpful to improve their quality of life and mental health.
Genetic testing: new challenges in the healthcare of women. Interview by Hannah Branch.
Hofmann, Wera; Branch, Hannah
2013-11-01
Dr Wera Hofmann is an expert in biochemistry and has over 12 years of human genetic diagnostics experience. Until 2006, she supervised a diagnostic unit for BRCA gene testing at the Interdisciplinary Center for Hereditary Breast Cancer (Max Delbrück Center, Berlin, Germany). She has also been the Managing Director of the Professional Association of German Human Geneticists, BVDH, which is a trade association. In 2008, Hofmann became a Medical Director at LifeCodexx (Konstanz, Germany), where she has worked on the development of a noninvasive prenatal diagnostic test that detects chromosomal aneuploidies in fetuses.
A Detection Device for the Signs of Human Life in Accident
NASA Astrophysics Data System (ADS)
Ning, Li; Ruilan, Zhang; Jian, Liu; Ruirui, Cheng; Yuhong, Diao
2017-12-01
A detection device for the signs of human life in accidents is a device used in emergency situations, such as the crash site. the scene of natural disasters, the battlefield ruins. it designed to detect the life signs of the distress under the injured ambulance vital signs devices. The device can on human vital signs, including pulse, respiration physiological signals to make rapid and accurate response. After some calculations, and after contrast to normal human physiological parameters given warning signals, in order for them to make timely ambulance judgment. In this case the device is required to do gymnastics convenience, ease of movement, power and detection of small flexible easy realization. This device has the maximum protection of the wounded safety significance.
Differences in change blindness to real-life scenes in adults with autism spectrum conditions.
Ashwin, Chris; Wheelwright, Sally; Baron-Cohen, Simon
2017-01-01
People often fail to detect large changes to visual scenes following a brief interruption, an effect known as 'change blindness'. People with autism spectrum conditions (ASC) have superior attention to detail and better discrimination of targets, and often notice small details that are missed by others. Together these predict people with autism should show enhanced perception of changes in simple change detection paradigms, including reduced change blindness. However, change blindness studies to date have reported mixed results in ASC, which have sometimes included no differences to controls or even enhanced change blindness. Attenuated change blindness has only been reported to date in ASC in children and adolescents, with no study reporting reduced change blindness in adults with ASC. The present study used a change blindness flicker task to investigate the detection of changes in images of everyday life in adults with ASC (n = 22) and controls (n = 22) using a simple change detection task design and full range of original scenes as stimuli. Results showed the adults with ASC had reduced change blindness compared to adult controls for changes to items of marginal interest in scenes, with no group difference for changes to items of central interest. There were no group differences in overall response latencies to correctly detect changes nor in the overall number of missed detections in the experiment. However, the ASC group showed greater missed changes for marginal interest changes of location, showing some evidence of greater change blindness as well. These findings show both reduced change blindness to marginal interest changes in ASC, based on response latencies, as well as greater change blindness to changes of location of marginal interest items, based on detection rates. The findings of reduced change blindness are consistent with clinical reports that people with ASC often notice small changes to less salient items within their environment, and are in-line with theories of enhanced local processing and greater attention to detail in ASC. The findings of lower detection rates for one of the marginal interest conditions may be related to problems in shifting attention or an overly focused attention spotlight.
Subjective expansion of extended time-spans in experienced meditators.
Wittmann, Marc; Otten, Simone; Schötz, Eva; Sarikaya, Anna; Lehnen, Hanna; Jo, Han-Gue; Kohls, Niko; Schmidt, Stefan; Meissner, Karin
2014-01-01
Experienced meditators typically report that they experience time slowing down in meditation practice as well as in everyday life. Conceptually this phenomenon may be understood through functional states of mindfulness, i.e., by attention regulation, body awareness, emotion regulation, and enhanced memory. However, hardly any systematic empirical work exists regarding the experience of time in meditators. In the current cross-sectional study, we investigated whether 42 experienced mindfulness meditation practitioners (with on average 10 years of experience) showed differences in the experience of time as compared to 42 controls without any meditation experience matched for age, sex, and education. The perception of time was assessed with a battery of psychophysical tasks assessing the accuracy of prospective time judgments in duration discrimination, duration reproduction, and time estimation in the milliseconds to minutes range as well with several psychometric instruments related to subjective time such as the Zimbardo Time Perspective Inventory, the Barratt Impulsivity Scale and the Freiburg Mindfulness Inventory. In addition, subjective time judgments on the current passage of time and retrospective time ranges were assessed. While subjective judgements of time were found to be significantly different between the two groups on several scales, no differences in duration estimates in the psychophysical tasks were detected. Regarding subjective time, mindfulness meditators experienced less time pressure, more time dilation, and a general slower passage of time. Moreover, they felt that the last week and the last month passed more slowly. Overall, although no intergroup differences in psychophysical tasks were detected, the reported findings demonstrate a close association between mindfulness meditation and the subjective feeling of the passage of time captured by psychometric instruments.
Precedents of perceived social support: personality and early life experiences.
Kitamura, T; Kijima, N; Watanabe, K; Takezaki, Y; Tanaka, E
1999-12-01
In order to examine the effects of personality and early life experiences on perceived social support, a total of 97 young Japanese women were investigated. Current interpersonal relationships were measured by an interview modified from Henderson et al.'s Interview Schedule for Social Interaction (ISSI). Personality was measured by Cloninger et al.'s Temperament and Character Inventory. Early life experiences at home and outside of home were also identified in the interview. The number of sources of perceived support was correlated with self-directness, while satisfaction with perceived support was correlated with novelty seeking and with low harm avoidance. No early life experiences--early loss of a parent, perceived parenting, childhood abuse experiences, experiences of being bullied and/or other life events--showed significant correlations with the number or satisfaction of supportive people. The quantity and quality of perception of social support differ in their link to personality, and perceived social support may, to some extent, be explainable in terms of personality.
NASA Technical Reports Server (NTRS)
Klein, Harold P.
1989-01-01
A brief review of the purposes and the results from the Viking Biology experiments is presented, in the expectation that the lessons learned from this mission will be useful in planning future approaches to the biological exploration of Mars. Since so little was then known about potential micro-environments on Mars, three different experiments were included in the Viking mission, each one based on different assumptions about what Martian organisms might be like. In addition to the Viking Biology Instrument (VBI), important corollary information was obtained from the Viking lander imaging system and from the molecular analysis experiments that were conducted using the gas chromatograph-mass spectrometer (GCMS) instrument. No biological objects were noted by the lander imaging instrument. The GCMS did not detect any organic compounds. A description of the tests conducted by the Gas Exchange Experiment, the Labeled Release experiment, and the Pyrolytic Release experiment is given. Results are discussed. Taken as a whole, the Viking data yielded no unequivocal evidence for a Martian biota at either landing site. The results also revealed the presence of one or more reactive oxidants in the surface material and these need to be further characterized, as does the range of micro-environments, before embarking upon future searches for extant life on Mars.
Life-stress and reactivity by gender in a longitudinal birth cohort at 30 and 35 years.
McLeod, Geraldine F H; Horwood, L J; Fergusson, D M; Boden, J M
2016-10-01
Previous literature has shown gender differences in reactivity to stressful life events. However, it is unclear whether gender differences in stress reactivity are consistent across a series of life event domains among longitudinal adult sample populations. Data were gathered from the Christchurch Health and Development Study (CHDS). The CHDS is a longitudinal birth cohort of 1265 children born in 1977 in Christchurch, New Zealand. Cohort members were questioned on their experience of, and distress from, a series of life event domains (interpersonal problems; victimization; illness/death; pregnancy/parenthood; employment/finance problems) spanning two age-periods 25-30 years (data collected in 2007) and 30-35 years (data collected in 2012). The data were pooled across observations and analyzed using population-averaged repeated-measures regression methods. Overall, men and women reported experiencing similar numbers of life events for each domain. However, men reported more victimization and more employment/financial problems; women reported more illness/death events. Women reported experiencing more distress per life event for the domains of interpersonal problems, illness/death and pregnancy/parenthood. Men and women reported similar distress per life event for the victimization and employment/finance domains. The results were robust to control for: child and adolescent factors (childhood abuse exposure; adolescent personality; mental health) and adult factors (mental health; self-esteem). These findings are consistent with a growing body of evidence indicating that some life events including interpersonal problems, illness/death and pregnancy/parenthood may be intrinsically more distressing for women. Detection of life event distress is important to aid in the prevention of mental/physical health problems.
MIT-KSC space life sciences telescience testbed
NASA Technical Reports Server (NTRS)
1989-01-01
A Telescience Life Sciences Testbed is being developed. The first phase of this effort consisted of defining the experiments to be performed, investigating the various possible means of communication between KSC and MIT, and developing software and hardware support. The experiments chosen were two vestibular sled experiments: a study of ocular torsion produced by Y axis linear acceleration, based on the Spacelab D-1 072 Vestibular Experiment performed pre- and post-flight at KSC; and an optokinetic nystagmus (OKN)/linear acceleration interaction experiment. These two experiments were meant to simulate actual experiments that might be performed on the Space Station and to be representative of space life sciences experiments in general in their use of crew time and communications resources.
Yeo, Jung Hee; Chun, Nami
2013-02-01
The purpose of this study was to identify influence of childbirth experience and postpartum depression on quality of life in women after birth. Two hundred and eleven postpartum women were asked to complete the questionnaires on their childbirth experience during their admission and on their postpartum depression and quality of life between one to three weeks after birth. Initial data were collected from February 1 to May 30, 2011 at two obstetric hospitals in Busan, Korea. Data were analyzed using t-test, ANOVA, Pearson correlation coefficients, and hierarchical multiple regression. The women's childbirth experience and postpartum depression were identified as factors influencing quality of life after birth. The model explained 50% of the variables. Results suggest that childbirth educators should include strategies to increase a positive childbirth experience and to decrease postpartum depression in their education programs in order to improve women's quality of life.
Opaas, Marianne; Varvin, Sverre
2015-01-01
Abstract Adverse and potentially traumatic experiences (PTEs) in childhood were examined among 54 adult refugee patients with pre-flight PTEs of war and human rights violations (HRVs) and related to mental health and quality of life at treatment start. Extent of childhood PTEs was more strongly related to mental health and quality of life than the extent of war and HRV experiences. Childhood PTEs were significantly related to arousal and avoidance symptoms of posttraumatic stress disorder (PTSD) and to quality of life, whereas pre-flight war and HRV experiences were significantly related to reexperiencing symptoms of PTSD only. Within childhood adversities, experiences of family violence and external violence, but not of loss and illness, were significantly related to increased mental health symptoms and reduced quality of life. These results point to the importance of taking childhood adverse experiences into account in research and treatment planning for adult refugees with war and HRVs trauma. PMID:26103604
The effect of positive writing on emotional intelligence and life satisfaction.
Wing, Joanna F; Schutte, Nicola S; Byrne, Brian
2006-10-01
This study explored the effect of writing about positive emotional experiences on emotional intelligence and life satisfaction. One hundred and seventy-five adults wrote about one of the following three topics: positive experiences with a cue for emotion regulation reflection, positive experiences without this cue, or a control writing topic. Multivariate analysis showed a significant time (pretest, posttest, and follow-up) by group effect. Writing about positive emotional experiences with an emotion regulation cue led to significant increases in emotional intelligence and life satisfaction at posttest and the increase in life satisfaction was maintained at 2-week follow-up. Further, participants who were cued to reflect on emotional regulation while writing about positive experiences rated their emotional intelligence significantly higher than the participants in the control writing group both at posttest and at follow-up. There were no significant differences in emotional intelligence or life satisfaction between those who were cued to reflect on emotional regulation while writing about positive experiences and those who wrote about positive experiences without such a cue. 2006 Wiley Periodicals, Inc.
Sýkorová, Zuzana; Ineichen, Kurt; Wiemken, Andres; Redecker, Dirk
2007-12-01
The community composition of arbuscular mycorrhizal fungi (AMF) was investigated in roots of four different plant species (Inula salicina, Medicago sativa, Origanum vulgare, and Bromus erectus) sampled in (1) a plant species-rich calcareous grassland, (2) a bait plant bioassay conducted directly in that grassland, and (3) a greenhouse trap experiment using soil and a transplanted whole plant from that grassland as inoculum. Roots were analyzed by AMF-specific nested polymerase chain reaction, restriction fragment length polymorphism screening, and sequence analyses of rDNA small subunit and internal transcribed spacer regions. The AMF sequences were analyzed phylogenetically and used to define monophyletic phylotypes. Overall, 16 phylotypes from several lineages of AMF were detected. The community composition was strongly influenced by the experimental approach, with additional influence of cultivation duration, substrate, and host plant species in some experiments. Some fungal phylotypes, e.g., GLOM-A3 (Glomus mosseae) and several members of Glomus group B, appeared predominantly in the greenhouse experiment or in bait plants. Thus, these phylotypes can be considered r strategists, rapidly colonizing uncolonized ruderal habitats in early successional stages of the fungal community. In the greenhouse experiment, for instance, G. mosseae was abundant after 3 months, but could not be detected anymore after 10 months. In contrast, other phylotypes as GLOM-A17 (G. badium) and GLOM-A16 were detected almost exclusively in roots sampled from plants naturally growing in the grassland or from bait plants exposed in the field, indicating that they preferentially occur in late successional stages of fungal communities and thus represent the K strategy. The only phylotype found with high frequency in all three experimental approaches was GLOM A-1 (G. intraradices), which is known to be a generalist. These results indicate that, in greenhouse trap experiments, it is difficult to establish a root-colonizing AMF community reflecting the diversity of these fungi in the field roots because fungal succession in such artificial systems may bias the results. However, the field bait plant approach might be a convenient way to study the influence of different environmental factors on AMF community composition directly under the field conditions. For a better understanding of the dynamics of AMF communities, it will be necessary to classify AMF phylotypes and species according to their life history strategies.
Pesticide storage and release in unsaturated soil in Illinois, USA
Roy, W.R.; Krapac, I.G.; Chou, S.-F.J.; Simmons, F.W.
2001-01-01
The chemical fate and movement of pesticides may be subject to transient storage in unsaturated soils during periods of light rainfall, and subsequent release into shallow groundwater by increased rainfall. The objective of this study was to conduct field-scale experiments to determine the relative importance of transient storage and subsequent release of agrichemicals from the vadose zone into potential aquifers. Two field-scale experiments were conducted under a rain exclusion shelter. In the 1 x experiment, atrazine and chlorpyrifos were applied at application-rate equivalents (1.6 kg ha-1 and 1.3 kg ha-1, respectively). In the 4x experiment, atrazine was applied in an amount that was four times greater than that usually applied to fields (6.7 kg ha-1). Water was either applied to simulate rain or withheld to simulate dry periods. In the 1 x experiment, atrazine was detected in the water samples whereas chlorpyrifos was not detected in the majority of the samples. The dry period imposed on the treatment plot did not appear to result in storage of the chemicals, whereas the wet period resulted in greater leaching of atrazine, although the concentrations remained less than the Maximum Contaminant Level of 3 ?? L-1. Both chemicals were detected in soil samples collected from a 20- to 30-cm depth, but it appeared that both chemicals dissipated before the field experiment was concluded. It appeared that the one-time application of atrazine and chlorpyrifos at the label rates did not result in a sufficient mass to be stored and flushed in significant concentrations to the saturated zone. When atrazine was applied at 4x and a longer drought period was imposed on the treatment plot, the resulting concentrations of dissolved atrazine were still less than 3 ??g L-1. Atrazine was detected in only the near-surface (0 to 15 cm) soil samples and the herbicide dissipated before the onset of the dry period in the treatment plot. The results of this field study demonstrated that atrazine and chlorpyrifos were not sufficiently persistent to be stored and then released in significantly large concentrations to the saturated zone. The dissipation half-life of atrazine in the 4x application was about 44 days. This study, in addition to others, suggested that atrazine may be less persistent in surface soil than has been generally reported.
Epistemological issues in the study of microbial life: alternative terran biospheres?
Cleland, Carol E
2007-12-01
The assumption that all life on Earth today shares the same basic molecular architecture and biochemistry is part of the paradigm of modern biology. This paper argues that there is little theoretical or empirical support for this widely held assumption. Scientists know that life could have been at least modestly different at the molecular level and it is clear that alternative molecular building blocks for life were available on the early Earth. If the emergence of life is, like other natural phenomena, highly probable given the right chemical and physical conditions then it seems likely that the early Earth hosted multiple origins of life, some of which produced chemical variations on life as we know it. While these points are often conceded, it is nevertheless maintained that any primitive alternatives to familiar life would have been eliminated long ago, either amalgamated into a single form of life through lateral gene transfer (LGT) or alternatively out-competed by our putatively more evolutionarily robust form of life. Besides, the argument continues, if such life forms still existed, we surely would have encountered telling signs of them by now. These arguments do not hold up well under close scrutiny. They reflect a host of assumptions that are grounded in our experience with large multicellular organisms and, most importantly, do not apply to microbial forms of life, which cannot be easily studied without the aid of sophisticated technologies. Significantly, the most powerful molecular biology techniques available-polymerase chain reaction (PCR) amplification of rRNA genes augmented by metagenomic analysis-could not detect such microbes if they existed. Given the profound philosophical and scientific importance that such a discovery would represent, a dedicated search for 'shadow microbes' (heretofore unrecognized 'alien' forms of terran microbial life) seems in order. The best place to start such a search is with puzzling (anomalous) phenomena, such as desert varnish, that resist classification as 'biological' or 'nonbiological'.
Amino acid chiral recognition using X-ray diffraction of thin films
NASA Technical Reports Server (NTRS)
Dragoi, D.; Kulleck, J.; Kanik, I.; Beegle, L. W.
2003-01-01
The astrobiological search for life, both extinct and extant, on other solar system bodies will take place via several planned lander missions to Mars, Europa and Titan. The detection and identification of organic molecules that have been associated with life is a major technical achievement. Terrestrial life utilizes organic molecules, such as amino acids, as its basic building block. Detection of an entometeric excess of L over D forms of amino acids would be a powerful sign that life had existed on Mars at one time.
College Students' Life Experiences in Korea and in the U.S.
ERIC Educational Resources Information Center
Kang, Sunwoo; Youn, Gahyun; Stilwell, William E.
2014-01-01
Even though college students may be faced with developmental life tasks that might lead them to cognitive and emotional growth, little is known about how college students' life experiences are related to their cultural values. Understanding college students' life across culture requires both exploratory and confirmatory approaches to examine (1)…
Parental Health and Children's Economic Well-Being
ERIC Educational Resources Information Center
Wagmiller, Robert L., Jr.; Lennon, Mary Clare; Kuang, Li
2008-01-01
The life course perspective emphasizes that past economic experiences and stage in the life course influence a family's ability to cope with negative life events such as poor health. However, traditional analytic approaches are not well-suited to examine how the impact of negative life events differs based on a family's past economic experiences,…
Salutogenic resources in relation to teachers' work-life balance.
Nilsson, Marie; Blomqvist, Kerstin; Andersson, Ingemar
2017-01-01
Experiencing work-life balance is considered a health promoting resource. To counter-balance the negative development of teachers' work situation, salutogenic resources need to be examined among teachers. To examine resources related to teachers' experience of their work-life balance. Using a cross-sectional design, a questionnaire was distributed to 455 teachers in compulsory schools in a Swedish community. A total of 338 teachers participated (74%). A multiple linear regression method was used for the analysis. Four variables in the regression model significantly explained work-life balance and were thereby possible resources: time experience at work; satisfaction with everyday life; self-rated health; and recovery. The strongest association with work-life balance was time experience at work. Except time experience at work, all were individual-related. This study highlights the importance of school management's support in reducing teachers' time pressure. It also emphasizes the need to address teachers' individual resources in relation to work-life balance. In order to support teachers' work-life balance, promote their well-being, and preventing teachers' attrition, we suggest that the school management would benefit from creating a work environment with strengthened resources.
Searching for Life: Early Earth, Mars and Beyond
NASA Technical Reports Server (NTRS)
DesMarais, David J.; Chang, Sherwood (Technical Monitor)
1996-01-01
We might be entering a golden age for exploring life throughout time and space. Rapid gene sequencing will better define our most distant ancestors. The earliest geologic evidence of life is now 3.8 billion years old. Organic matter and submicron-sized morphologies have been preserved in the martian crust for billions of years. Several new missions to Mars are planned, with a high priority on the search for life, past or present. The recent discovery of large extrasolar planets has heightened interest in spacecraft to detect small, earth-like planets. A recent workshop discussed strategies for life detection on such planets. There is much to anticipate in the near future.
Microwave life detector for buried victims using neutrodyning loop based system
NASA Astrophysics Data System (ADS)
Tahar J., Bel Hadj
2009-07-01
This paper describes a new design of an electromagnetic life detector for the detection of buried victims. The principle of the microwave life sensor is based on the detection of the modulated part of a scattered wave which is generated by the breathing activity of the victim. Those movements generate a spectral component located in the low frequency range, which for most of the cases, is located in a spectrum extending from 0.18 Hz to 0.34 Hz. The detection process requires high sensitivity with respect to breathing movements and, simultaneously, a relative insensitivity for other non-modulated or modulated parasitic signals. Developed microwave system, generating a frequency adjustable between 500 MHz and 1 GHz, is based on a neutrodyning loop required to cancel any non-modulated background and reflected signals in order to get better receiver sensitivity without introducing supplementary distortions on the received signal. Life signal is considered practically periodic that facilitates the extraction of this spectral component using several processing techniques, such as adaptive filtering and correlation permitting to ameliorate the detection range to be more than 15 m in low-loss medium. Detection range is a fundamental parameter for a microwave life detector. A range around 1 m doesn't have a large interest for this application. To attain a range more than 15 m, while guaranteeing professional performances, the technology has to optimize the system parameters as well as the involved signal processing for the purpose of overcoming the presence of obstacles, attenuation, and noise perturbation. This constitutes the main contribution of the present work. Experimental measurements have confirmed the potentiality of this microwave technique for life detector with best space covering detection.
Independent effects of early-life experience and trait aggression on cardiovascular function
Rana, Samir; Pugh, Phyllis C.; Katz, Erin; Stringfellow, Sara A.; Lin, Chee Paul; Wyss, J. Michael; Stauss, Harald M.; White, C. Roger; Clinton, Sarah M.
2016-01-01
Early-life experience (ELE) can significantly affect life-long health and disease, including cardiovascular function. Specific dimensions of emotionality also modify risk of disease, and aggressive traits along with social inhibition have been established as independent vulnerability factors for the progression of cardiovascular disease. Yet, the biological mechanisms mediating these associations remain poorly understood. The present study utilized the inherently stress-susceptible and socially inhibited Wistar-Kyoto rats to determine the potential influences of ELE and trait aggression (TA) on cardiovascular parameters throughout the lifespan. Pups were exposed to maternal separation (MS), consisting of daily 3-h separations of the entire litter from postnatal day (P)1 to P14. The rats were weaned at P21, and as adults were instrumented for chronic radiotelemetry recordings of blood pressure and heart rate (HR). Adult aggressive behavior was assessed using the resident-intruder test, which demonstrated that TA was independent of MS exposure. MS-exposed animals (irrespective of TA) had significantly lower resting HR accompanied by increases in HR variability. No effects of MS on resting blood pressure were detected. In contrast, TA correlated with increased resting mean, systolic, and diastolic arterial pressures but had no effect on HR. TA rats (relative to nonaggressive animals) also manifested increased wall-to-lumen ratio in the thoracic aorta, increased sensitivity to phenylephrine-induced vascular contractility, and increased norepinephrine content in the heart. Together these data suggest that ELE and TA are independent factors that impact baseline cardiovascular function. PMID:27280432
Gender Differences in Caregiving at End of Life: Implications for Hospice Teams
Washington, Karla T.; Pike, Kenneth C.; Parker Oliver, Debra; Albright, David L.; Lewis, Alexandria M.
2015-01-01
Abstract Background: Researchers have identified important gender differences in the experience of caring for a family member or friend living with advanced disease; however, trends suggest that these differences may be diminishing over time in response to changing gender roles. In addition, while many studies have found caregiving experiences and outcomes to be poorer among female caregivers, noteworthy exceptions exist. Objective: The primary aim of this exploratory study was to determine how, if at all, current day caregiving at end of life varies by gender. Methods: We conducted a secondary analysis of data from a multisite randomized controlled trial of a family caregiving intervention performed between 2010 and 2014. We compared female and male hospice family caregivers on baseline variables using χ2 tests for association of categorical variables and t-tests for continuous variables. Our sample included 289 family caregivers of individuals receiving services from one of two hospice agencies located in the northwestern United States. Demographic data and other categorical variables of interest were provided via caregiver self-report using an instrument created specifically for this study. Reaction to caregiving and caregiving burden were measured using the Caregiver Reaction Assessment (CRA). Results: As it related to caregiving, females had significantly lower self-esteem and more negative impact on their schedule, health, and family support than males. No gender differences were detected with regard to the impact of caregiving on individuals' finances. Conclusions: Despite changing social expectations, pronounced gender differences persist in caregiving at the end of life. PMID:26484426
Kery, M.; Gregg, K.B.
2003-01-01
1. Most plant demographic studies follow marked individuals in permanent plots. Plots tend to be small, so detectability is assumed to be one for every individual. However, detectability could be affected by factors such as plant traits, time, space, observer, previous detection, biotic interactions, and especially by life-state. 2. We used a double-observer survey and closed population capture-recapture modelling to estimate state-specific detectability of the orchid Cleistes bifaria in a long-term study plot of 41.2 m2. Based on AICc model selection, detectability was different for each life-state and for tagged vs. previously untagged plants. There were no differences in detectability between the two observers. 3. Detectability estimates (SE) for one-leaf vegetative, two-leaf vegetative, and flowering/fruiting states correlated with mean size of these states and were 0.76 (0.05), 0.92 (0.06), and 1 (0.00), respectively, for previously tagged plants, and 0.84 (0.08), 0.75 (0.22), and 0 (0.00), respectively, for previously untagged plants. (We had insufficient data to obtain a satisfactory estimate of previously untagged flowering plants). 4. Our estimates are for a medium-sized plant in a small and intensively surveyed plot. It is possible that detectability is even lower for larger plots and smaller plants or smaller life-states (e.g. seedlings) and that detectabilities < 1 are widespread in plant demographic studies. 5. State-dependent detectabilities are especially worrying since they will lead to a size- or state-biased sample from the study plot. Failure to incorporate detectability into demographic estimation methods introduces a bias into most estimates of population parameters such as fecundity, recruitment, mortality, and transition rates between life-states. We illustrate this by a simple example using a matrix model, where a hypothetical population was stable but, due to imperfect detection, wrongly projected to be declining at a rate of 8% per year. 6. Almost all plant demographic studies are based on models for discrete states. State and size are important predictors both for demographic rates and detectability. We suggest that even in studies based on small plots, state- or size-specific detectability should be estimated at least at some point to avoid biased inference about the dynamics of the population sampled.
Predicting the remaining service life of concrete
DOE Office of Scientific and Technical Information (OSTI.GOV)
Clifton, J.F.
1991-11-01
Nuclear power plants are providing, currently, about 17 percent of the U.S. electricity and many of these plants are approaching their licensed life of 40 years. The U.S. Nuclear Regulatory Commission and the Department of Energy`s Oak Ridge National Laboratory are carrying out a program to develop a methodology for assessing the remaining safe-life of the concrete components and structures in nuclear power plants. This program has the overall objective of identifying potential structural safety issues, as well as acceptance criteria, for use in evaluations of nuclear power plants for continued service. The National Institute of Standards and Technology (NIST)more » is contributing to this program by identifying and analyzing methods for predicting the remaining life of in-service concrete materials. This report examines the basis for predicting the remaining service lives of concrete materials of nuclear power facilities. Methods for predicting the service life of new and in-service concrete materials are analyzed. These methods include (1) estimates based on experience, (2) comparison of performance, (3) accelerated testing, (4) stochastic methods, and (5) mathematical modeling. New approaches for predicting the remaining service lives of concrete materials are proposed and recommendations for their further development given. Degradation processes are discussed based on considerations of their mechanisms, likelihood of occurrence, manifestations, and detection. They include corrosion, sulfate attack, alkali-aggregate reactions, frost attack, leaching, radiation, salt crystallization, and microbiological attack.« less
Stressful life events and catechol-O-methyl-transferase (COMT) gene in bipolar disorder.
Hosang, Georgina M; Fisher, Helen L; Cohen-Woods, Sarah; McGuffin, Peter; Farmer, Anne E
2017-05-01
A small body of research suggests that gene-environment interactions play an important role in the development of bipolar disorder. The aim of the present study is to contribute to this work by exploring the relationship between stressful life events and the catechol-O-methyl-transferase (COMT) Val 158 Met polymorphism in bipolar disorder. Four hundred eighty-two bipolar cases and 205 psychiatrically healthy controls completed the List of Threatening Experiences Questionnaire. Bipolar cases reported the events experienced 6 months before their worst depressive and manic episodes; controls reported those events experienced 6 months prior to their interview. The genotypic information for the COMT Val 158 Met variant (rs4680) was extracted from GWAS analysis of the sample. The impact of stressful life events was moderated by the COMT genotype for the worst depressive episode using a Val dominant model (adjusted risk difference = 0.09, 95% confidence intervals = 0.003-0.18, P = .04). For the worst manic episodes no significant interactions between COMT and stressful life events were detected. This is the first study to explore the relationship between stressful life events and the COMT Val 158 Met polymorphism focusing solely on bipolar disorder. The results of this study highlight the importance of the interplay between genetic and environmental factors for bipolar depression. © 2017 Wiley Periodicals, Inc.
NASA Technical Reports Server (NTRS)
Wang, Alian; Haskin, L. A.; Gillis, J. J.
2003-01-01
The widely accepted minimum requirements for life on Earth include the presence of water and accessible sources of carbon. We assume that the same criteria must hold for putative life on past or present Mars. The evidence for CO2 and H2O at or near the Martian surface, carbon in Martian meteorites, aqueous alteration, and probable hydrothermal activity suggest that conditions conducive to the origin and evolution of life on Mars may have existed for long periods of time and may still obtain at present. Surface exploration on Mars that enables the direct detection of water in minerals and of organic carbon (including not just organic and biogenic materials but their degradation products such as kerogen-like hydrocarbons and graphitized carbon) that might be products or residues of biologic activity, is crucial. The search for evidence of life, past or present, will nevertheless be difficult. The lack of direct evidence for organic carbon and the low amounts of water found in the soils at the Viking sites demonstrated the difficulties. Recent results of GRS experiment of Odyssey mission indicated the existence of abundant water ice beneath the Mars surface. Mineralogical evidence for the presence of carbonate, sulfates, or clay minerals, products of weathering and aqueous deposition, have not been identified unambiguously on Mars. Rocks such as shales and, more particularly, limestones, which we associate with moist and benign environments on Earth, are evidently not abundant. Presumably, then, neither were the photosynthetic organisms that might have produced them. In addition, the harsh present environment on Mars (e.g., dryness, low temperatures, large temperature cycles, high level of UV light on the surface, frequent dust storms, etc.) can both destroy carbon- and water-bearing materials and hide them. Therefore, directly detecting life-related materials on Mars was likened to seeking and examining proverbial needles in haystacks. We argue that survey type instruments, that can frequently and quickly check a relatively large amount of material at many locations during a mission, are essential.
Cömert, Itır Tarı; Özyeşil, Zümra Atalay; Burcu Özgülük, S
2016-02-01
The aim of the current study was to investigate the contributions of sad childhood experiences, depression, anxiety, and stress, existence of a sense of meaning, and pursuit of meaning in explaining life satisfaction of young adults in Turkey. The sample comprised 400 undergraduate students ( M age = 20.2 yr.) selected via random cluster sampling. There were no statistically significant differences between men and women in terms of their scores on depression, existence of meaning, pursuit of meaning, and life satisfaction scores. However, there were statistically significant differences between men and women on the sad childhood experiences, anxiety and stress. In heirarchical regression analysis, the model as a whole was significant. Depression and existence of meaning in life made unique significant contributions to the variance in satisfaction in life. Students with lower depression and with a sense of meaning in life tended to be more satisfied with life.
Detecting Molecular Signatures of Life on Mars: the Life Marker Chip (lmc) Instrument
NASA Astrophysics Data System (ADS)
Derveni, Mariliza
In recent years, the rise of interest in planetary exploration and the emergence of Astrobiology as a promising field of research have lead to a number of programmes aiming to develop sensitive instruments for the detection of the molecular signatures of life in extreme environments. An antibody assay-based life detection instrument, the Life Marker Chip (LMC), is currently under development by a UK-lead international consortium for the European Space Agency's (ESA) ExoMars rover. This forms part of the joint ESA/NASA Mars exploration programme with the ExoMars Rover currently scheduled for launch in 2018. The organic molecules targeted for Life detection by the LMC are based on an assumption of "Earth-like" Life on Mars -extinct and/or extant. The molecular targets for the LMC have been chosen to represent markers of extinct Life, extant Life, abiotic chemistry (e.g. of meteoritic origin) and mission-borne Earth contamination. The LMC incorporates integrated liquid sample extraction and processing for dry Martian samples, which will be collected from up to 2m below the surface of Mars, where organic molecules, if present, are expected to be better preserved. The core technology of the LMC is a combination of optical evanescent waveguides, micro-fluidics, immuno-microarrays with fluorescent labels and CCD detector readout. Phage display recombinant antibody technology has been employed in order to acquire antibodies against a number of the LMC target molecules. The LMC hardware is currently in a breadboard phase of development. The recombinant antibody development for LMC targets is an on-going project, and testing of Earth-analogue Martian samples has been initiated
Daily Life Experience and Somatic Symptoms: A Preliminary Report.
1981-03-01
AAO7 9 859 STATE UNIV OF NEW YORK AT STONY BROOK FG 5/10 DAILY LIFE EXPERIENCE AND SOMATIC SYMPTOMS: A PRELIMINARY REPOR--ETC(U) MAR 8I A A STONE. J...Experience and Somatic Symptoms: A Preliminary Report Arthur A. Stone Long Island Research Institute and Department of Psychiatry arnd Behavioral...TITLE (and S..,til.) s. ALF - , rlA9OQ COVERED Daily Life Experience and Somatic Symptoms: A Technical p " Preliminary Report, EL..... S. PERFORMING
Visual monitoring of autonomous life sciences experimentation
NASA Technical Reports Server (NTRS)
Blank, G. E.; Martin, W. N.
1987-01-01
The design and implementation of a computerized visual monitoring system to aid in the monitoring and control of life sciences experiments on board a space station was investigated. A likely multiprocessor design was chosen, a plausible life science experiment with which to work was defined, the theoretical issues involved in the programming of a visual monitoring system for the experiment was considered on the multiprocessor, a system for monitoring the experiment was designed, and simulations of such a system was implemented on a network of Apollo workstations.
The Experience of Critical Self-Reflection by Life Coaches: A Phenomenological Study
ERIC Educational Resources Information Center
Shaw, Deanna Lynn
2012-01-01
The purpose of this study was to describe the experience of critical self-reflection by life coaches. Life coaching is expanding within many disciplines including education, health care, business, social work, and wellness. Life coaching involves a coach working with an individual or groups aimed at effecting change for professional and personal…
Imagining the Alternatives to Life Prolonging Treatments: Elders' Beliefs about the Dying Experience
ERIC Educational Resources Information Center
Winter, Laraine; Parker, Barbara; Schneider, Melissa
2007-01-01
Deciding for or against a life-prolonging treatment represents a choice between prolonged life and death. When the death alternative is not described, individuals must supply their own assumptions. How do people imagine the experience of dying? The authors asked 40 elderly people open-ended questions about dying without 4 common life-prolonging…
Dreams Worth Pursuing: How College Students Develop and Articulate Their Purpose in Life
ERIC Educational Resources Information Center
Schluckebier, Michael Edward
2013-01-01
The purpose of this study was to describe the experiences undergraduate students cite as helping them develop and articulate their purpose in life. Purpose in life, as a construct, is associated with many positive attributes associated with life in general, and the college experience specifically; however, it is also closely related to other…
NASA Astrophysics Data System (ADS)
2012-04-01
A collection of archive materials from the family of Sir John F W Herschel (1792-1871) is now available for study at Harry Ransom Center at the University of Texas at Austin. The collection includes much of John Herschel's correspondence as well as examples of his cyanotypes. European Southern Observatory data from the Very Large Telescope have enabled astronomers to say with confidence that they can detect signs of life on Earth using spectropolarimetry of earthshine: light from the Earth's atmosphere reflected from the Moon. This is an important step towards detecting life on exoplanets.
NASA Astrophysics Data System (ADS)
Webb, S.
2013-09-01
Until relatively recently, many authors have assumed that if extraterrestrial life is discovered it will be via the discovery of extraterrestrial intelligence: we can best try to detect life by adopting the SETI approach of trying to detect beacons or artefacts. The Rio Scale, proposed by Almár and Tarter in 2000, is a tool for quantifying the potential significance for society of any such reported detection. However, improvements in technology and advances in astrobiology raise the possibility that the discovery of extraterrestrial life will instead be via the detection of atmospheric biosignatures. The London Scale, proposed by Almár in 2010, attempts to quantify the potential significance of the discovery of extraterrestrial life rather than extraterrestrial intelligence. What might be the consequences of the announcement of a discovery that ranks low on the London Scale? In other words, what might be society's reaction if 'first contact' is via the remote sensing of the byproducts of unicellular organisms rather than with the products of high intelligence? Here, I examine some possible reactions to that question; in particular, I discuss how such an announcement might affect our views of life here on Earth and of humanity's place in the universe.
ERIC Educational Resources Information Center
Lowe, Janet; Gayle, Vernon
2007-01-01
This study explores the dimensions of the work/life/study balance and its influence on student participation in higher education, through a case study of the experience of higher education students, studying both full time and part time, in a Scottish further education college. The experience of the students and the work/life/study challenges that…
Smart LED lighting for major reductions in power and energy use for plant lighting in space
NASA Astrophysics Data System (ADS)
Poulet, Lucie
Launching or resupplying food, oxygen, and water into space for long-duration, crewed missions to distant destinations, such as Mars, is currently impossible. Bioregenerative life-support systems under development worldwide involving photoautotrophic organisms offer a solution to the food dilemma. However, using traditional Earth-based lighting methods, growth of food crops consumes copious energy, and since sunlight will not always be available at different space destinations, efficient electric lighting solutions are badly needed to reduce the Equivalent System Mass (ESM) of life-support infrastructure to be launched and transported to future space destinations with sustainable human habitats. The scope of the present study was to demonstrate that using LEDs coupled to plant detection, and optimizing spectral and irradiance parameters of LED light, the model crop lettuce (
A Bionic Camera-Based Polarization Navigation Sensor
Wang, Daobin; Liang, Huawei; Zhu, Hui; Zhang, Shuai
2014-01-01
Navigation and positioning technology is closely related to our routine life activities, from travel to aerospace. Recently it has been found that Cataglyphis (a kind of desert ant) is able to detect the polarization direction of skylight and navigate according to this information. This paper presents a real-time bionic camera-based polarization navigation sensor. This sensor has two work modes: one is a single-point measurement mode and the other is a multi-point measurement mode. An indoor calibration experiment of the sensor has been done under a beam of standard polarized light. The experiment results show that after noise reduction the accuracy of the sensor can reach up to 0.3256°. It is also compared with GPS and INS (Inertial Navigation System) in the single-point measurement mode through an outdoor experiment. Through time compensation and location compensation, the sensor can be a useful alternative to GPS and INS. In addition, the sensor also can measure the polarization distribution pattern when it works in multi-point measurement mode. PMID:25051029
[A review of mixed gas detection system based on infrared spectroscopic technique].
Dang, Jing-Min; Fu, Li; Yan, Zi-Hui; Zheng, Chuan-Tao; Chang, Yu-Chun; Chen, Chen; Wang, Yi-Din
2014-10-01
In order to provide the experiences and references to the researchers who are working on infrared (IR) mixed gas detection field. The proposed manuscript reviews two sections of the aforementioned field, including optical multiplexing structure and detection method. At present, the coherent light sources whose representative are quantum cascade laser (QCL) and inter-band cascade laser(ICL) become the mainstream light source in IR mixed gas detection, which replace the traditional non-coherent light source, such as IR radiation source and IR light emitting diode. In addition, the photon detector which has a super high detectivity and very short response time is gradually beyond thermal infrared detector, dominant in the field of infrared detector. The optical multiplexing structure is the key factor of IR mixed gas detection system, which consists of single light source multi-plexing detection structure and multi light source multiplexing detection structure. Particularly, single light source multiplexing detection structure is advantages of small volume and high integration, which make it a plausible candidate for the portable mixed gas detection system; Meanwhile, multi light source multiplexing detection structure is embodiment of time division multiplex, frequency division multiplexing and wavelength division multiplexing, and become the leading structure of the mixed gas detection system because of its wider spectral range, higher spectral resolution, etc. The detection method applied to IR mixed gas detection includes non-dispersive infrared (NDIR) spectroscopy, wavelength and frequency-modulation spectroscopy, cavity-enhanced spectroscopy and photoacoustic spectroscopy, etc. The IR mixed gas detection system designed by researchers after recognizing the whole sections of the proposed system, which play a significant role in industrial and agricultural production, environmental monitoring, and life science, etc.
Hua, Fangyuan; Fletcher, Robert J.; Sieving, Kathryn E.; Dorazio, Robert M.
2013-01-01
Predation risk is widely hypothesized as an important force structuring communities, but this potential force is rarely tested experimentally, particularly in terrestrial vertebrate communities. How animals respond to predation risk is generally considered predictable from species life-history and natural-history traits, but rigorous tests of these predictions remain scarce. We report on a large-scale playback experiment with a forest bird community that addresses two questions: (i) does perceived predation risk shape the richness and composition of a breeding bird community? And (ii) can species life-history and natural-history traits predict prey community responses to different types of predation risk? On 9 ha plots, we manipulated cues of three avian predators that preferentially prey on either adult birds or offspring, or both, throughout the breeding season. We found that increased perception of predation risk led to generally negative responses in the abundance, occurrence and/or detection probability of most prey species, which in turn reduced the species richness and shifted the composition of the breeding bird community. Species-level responses were largely predicted from the key natural-history trait of body size, but we did not find support for the life-history theory prediction of the relationship between species' slow/fast life-history strategy and their response to predation risk.
Denning, Kathryn
2011-02-13
Although astrobiological or SETI detections are possible, actual invasions of sentient extra-terrestrials or plagues of escaped alien microbes are unlikely. Therefore, an anthropological perspective on the question suggests that in the event of a detection, the vast majority of humanity will be dealing not with extra-terrestrial life itself (whether intelligent or not, local or distant), but with human perceptions and representations of that alien life. These will, inevitably, derive from the powerful influences of culture and individual psychology, as well as from science. It may even be argued that in most detection scenarios, the scientific data (and debates about their interpretation) will be nigh-irrelevant to the unfolding of international public reaction. 'Extra-terrestrial life' will, in short, go wild. From this premise, some key questions emerge, including: what can scientists reasonably do to prepare, and what should their responsibilities be, particularly with respect to information dissemination and public discussions about policy? Then, moving beyond the level of immediate practicalities, we might also ask some more anthropological questions: what are the cultural substrates underneath the inquiries of Western science into extra-terrestrial life? In particular, what are the stories we have been told about discovery of rare life, and about contact with other beings, and do these stories really mean what we think they do? Might a closer look at those narratives help us gain perspective on the quest to find extra-terrestrial life, and on our quest to prepare for the consequences of detection?
Continuing the biological exploration of Mars
NASA Technical Reports Server (NTRS)
Klein, Harold P.
1988-01-01
Mars has been an object of interest for the better part of this century. To a biologist, Mars assumes special importance because many aspects of the theory of chemical evolution for the origin of life can be tested there. The central idea of this theory is that life on a suitable planet arises through a process in which the so-called biogenic elements combine to form increasingly more complex molecules under the influence of naturally-occurring energy sources ultimately resulting in the formation of replicating organic molecules. The biogenic elements are present on Mars today. Furthermore, the available evidence also strongly suggests that Mars may have had an early history similar to that of the Earth, including a period in which large amounts of liquid water once flowed on its surface and a denser atmosphere and higher global temperatures prevailed. This is important since many lines of evidence indicate that living organisms were already present on the Earth within the first billion years after its formation at a time when the environment on Mars may have closely resembled that of Earth. Our current knowledge of the state of chemical evolution on Mars can best be described as paradoxical. Most of what we have learned has come from experiments performed on the Viking landers. The combination of planned investigations covered a broad range of techniques to detect signs of chemical evolution. The most surprising data from all of these was the absence of any detectable quantities of organic compounds at the two landing sites. On the other hand, the Viking experiments did indicate that the Martian surface samples contained unidentified strong oxidant(s) that could account for their absence.
Search for life on Mars in surface samples: Lessons from the 1999 Marsokhod rover field experiment
Newsom, Horton E.; Bishop, J.L.; Cockell, C.; Roush, T.L.; Johnson, J. R.
2001-01-01
The Marsokhod 1999 field experiment in the Mojave Desert included a simulation of a rover-based sample selection mission. As part of this mission, a test was made of strategies and analytical techniques for identifying past or present life in environments expected to be present on Mars. A combination of visual clues from high-resolution images and the detection of an important biomolecule (chlorophyll) with visible/near-infrared (NIR) spectroscopy led to the successful identification of a rock with evidence of cryptoendolithic organisms. The sample was identified in high-resolution images (3 times the resolution of the Imager for Mars Pathfinder camera) on the basis of a green tinge and textural information suggesting the presence of a thin, partially missing exfoliating layer revealing the organisms. The presence of chlorophyll bands in similar samples was observed in visible/NIR spectra of samples in the field and later confirmed in the laboratory using the same spectrometer. Raman spectroscopy in the laboratory, simulating a remote measurement technique, also detected evidence of carotenoids in samples from the same area. Laboratory analysis confirmed that the subsurface layer of the rock is inhabited by a community of coccoid Chroococcidioposis cyanobacteria. The identification of minerals in the field, including carbonates and serpentine, that are associated with aqueous processes was also demonstrated using the visible/NIR spectrometer. Other lessons learned that are applicable to future rover missions include the benefits of web-based programs for target selection and for daily mission planning and the need for involvement of the science team in optimizing image compression schemes based on the retention of visual signature characteristics. Copyright 2000 by the American Geophysical Union.
McCoy, K B; Derecho, I; Wong, T; Tran, H M; Huynh, T D; La Duc, M T; Venkateswaran, K; Mogul, R
2012-09-01
The microbiology of the spacecraft assembly process is of paramount importance to planetary exploration, as the biological contamination that can result from remote-enabled spacecraft carries the potential to impact both life-detection experiments and extraterrestrial evolution. Accordingly, insights into the mechanisms and range of extremotolerance of Acinetobacter radioresistens 50v1, a Gram-negative bacterium isolated from the surface of the preflight Mars Odyssey orbiter, were gained by using a combination of microbiological, enzymatic, and proteomic methods. In summary, A. radioresistens 50v1 displayed a remarkable range of survival against hydrogen peroxide and the sequential exposures of desiccation, vapor and plasma phase hydrogen peroxide, and ultraviolet irradiation. The survival is among the highest reported for non-spore-forming and Gram-negative bacteria and is based upon contributions from the enzyme-based degradation of H(2)O(2) (catalase and alkyl hydroperoxide reductase), energy management (ATP synthase and alcohol dehydrogenase), and modulation of the membrane composition. Together, the biochemical and survival features of A. radioresistens 50v1 support a potential persistence on Mars (given an unintended or planned surface landing of the Mars Odyssey orbiter), which in turn may compromise the scientific integrity of future life-detection missions.
Survival of Glycolaldehyde and Production of Sugar Compounds via Comet Impact Delivery
NASA Astrophysics Data System (ADS)
Zellner, N.; McCaffrey, V.; Crake, C.; Butler, J.; Robbins, J.; Fodor, A.
2017-12-01
Impact experiments using glycolaldehyde (GLA), a two-carbon sugar precursor that has been detected in regions of the interstellar medium and on comets, have been conducted at the Experimental Impact Laboratory at NASA's Johnson Space Center. Samples of GLA and GLA mixed with montmorillonite clays were subjected to the pressure conditions that are found during impact delivery of biomolecules by comets, asteroids, or meteors; pressures ranged from 4.5 GPa to 25 GPa. Results show that large amounts of GLA survived the impacts and moderate amounts of threose, erythrose, and glycolic acid were produced in these impacts. Total amounts are dependent on impact pressure. Ethylene glycol, a reduced variant of GLA that has also been detected in the interstellar medium and on comets, was also produced. The results of these experimental impacts provide evidence that large amounts of GLA, EG, and other biomolecules were available on habitable moons or planets, especially during the era of late heavy bombardment ( 4.2 to 3.7 billion years ago) when life may have been developing on Earth. The presence and availability of these biomolecules, under appropriate conditions, may be important for understanding the origin of life as we know it. Glycolaldehyde in particular, may be an important molecule in the production of ribose, the five-carbon sugar in RNA.
The impact of age vs. life experience on the gender role attitudes of women in different cohorts.
Lynott, P P; McCandless, N J
2000-01-01
Much research has concluded that the gender role attitudes of older women are more traditional in orientation. This line of research, however, has often confounded the impact of age and cohort. Consequently, cohort differences in life experiences have not been systematically explored. This study addresses the relationship between age and gender role attitudes, taking into account the potential mediating effects of life experiences and controlling for cohort. The conclusions suggest that the impact of age on gender role attitudes is not as strong as might be expected. Rather, the results show that the life experiences of different cohorts are better predictors of gender role attitudes among older women, though such experiences do not have the same impact on all women.
Lindensmith, Christian A.; Rider, Stephanie; Bedrossian, Manuel; Wallace, J. Kent; Serabyn, Eugene; Showalter, G. Max; Deming, Jody W.; Nadeau, Jay L.
2016-01-01
Sea ice is an analog environment for several of astrobiology’s near-term targets: Mars, Europa, Enceladus, and perhaps other Jovian or Saturnian moons. Microorganisms, both eukaryotic and prokaryotic, remain active within brine channels inside the ice, making it unnecessary to penetrate through to liquid water below in order to detect life. We have developed a submersible digital holographic microscope (DHM) that is capable of resolving individual bacterial cells, and demonstrated its utility for immediately imaging samples taken directly from sea ice at several locations near Nuuk, Greenland. In all samples, the appearance and motility of eukaryotes were conclusive signs of life. The appearance of prokaryotic cells alone was not sufficient to confirm life, but when prokaryotic motility occurred, it was rapid and conclusive. Warming the samples to above-freezing temperatures or supplementing with serine increased the number of motile cells and the speed of motility; supplementing with serine also stimulated chemotaxis. These results show that DHM is a useful technique for detection of active organisms in extreme environments, and that motility may be used as a biosignature in the liquid brines that persist in ice. These findings have important implications for the design of missions to icy environments and suggest ways in which DHM imaging may be integrated with chemical life-detection suites in order to create more conclusive life detection packages. PMID:26812683
Lindensmith, Christian A; Rider, Stephanie; Bedrossian, Manuel; Wallace, J Kent; Serabyn, Eugene; Showalter, G Max; Deming, Jody W; Nadeau, Jay L
2016-01-01
Sea ice is an analog environment for several of astrobiology's near-term targets: Mars, Europa, Enceladus, and perhaps other Jovian or Saturnian moons. Microorganisms, both eukaryotic and prokaryotic, remain active within brine channels inside the ice, making it unnecessary to penetrate through to liquid water below in order to detect life. We have developed a submersible digital holographic microscope (DHM) that is capable of resolving individual bacterial cells, and demonstrated its utility for immediately imaging samples taken directly from sea ice at several locations near Nuuk, Greenland. In all samples, the appearance and motility of eukaryotes were conclusive signs of life. The appearance of prokaryotic cells alone was not sufficient to confirm life, but when prokaryotic motility occurred, it was rapid and conclusive. Warming the samples to above-freezing temperatures or supplementing with serine increased the number of motile cells and the speed of motility; supplementing with serine also stimulated chemotaxis. These results show that DHM is a useful technique for detection of active organisms in extreme environments, and that motility may be used as a biosignature in the liquid brines that persist in ice. These findings have important implications for the design of missions to icy environments and suggest ways in which DHM imaging may be integrated with chemical life-detection suites in order to create more conclusive life detection packages.
Life sciences payloads for Shuttle
NASA Technical Reports Server (NTRS)
Dunning, R. W.
1974-01-01
The Life Sciences Program for utilization of the Shuttle in the 1980's is presented. Requirements for life sciences research experiments in space flight are discussed along with study results of designs to meet these requirements. The span of life sciences interests in biomedicine, biology, man system integration, bioinstrumentation and life support/protective systems is described with a listing of the research areas encompassed in these descriptions. This is followed by a description of the approach used to derive from the life sciences disciplines, the research functions and instrumentation required for an orbital research program. Space Shuttle design options for life sciences experiments are identified and described. Details are presented for Spacelab laboratories for dedicated missions, mini-labs with carry on characteristics and carry on experiments for shared payload missions and free flying satellites to be deployed and retrieved by the Shuttle.
Traveling-wave tube reliability estimates, life tests, and space flight experience
NASA Technical Reports Server (NTRS)
Lalli, V. R.; Speck, C. E.
1977-01-01
Infant mortality, useful life, and wearout phase of twt life are considered. The performance of existing developmental tubes, flight experience, and sequential hardware testing are evaluated. The reliability history of twt's in space applications is documented by considering: (1) the generic parts of the tube in light of the manner in which their design and operation affect the ultimate reliability of the device, (2) the flight experience of medium power tubes, and (3) the available life test data for existing space-qualified twt's in addition to those of high power devices.
Experimental methods of molecular matter-wave optics.
Juffmann, Thomas; Ulbricht, Hendrik; Arndt, Markus
2013-08-01
We describe the state of the art in preparing, manipulating and detecting coherent molecular matter. We focus on experimental methods for handling the quantum motion of compound systems from diatomic molecules to clusters or biomolecules.Molecular quantum optics offers many challenges and innovative prospects: already the combination of two atoms into one molecule takes several well-established methods from atomic physics, such as for instance laser cooling, to their limits. The enormous internal complexity that arises when hundreds or thousands of atoms are bound in a single organic molecule, cluster or nanocrystal provides a richness that can only be tackled by combining methods from atomic physics, chemistry, cluster physics, nanotechnology and the life sciences.We review various molecular beam sources and their suitability for matter-wave experiments. We discuss numerous molecular detection schemes and give an overview over diffraction and interference experiments that have already been performed with molecules or clusters.Applications of de Broglie studies with composite systems range from fundamental tests of physics up to quantum-enhanced metrology in physical chemistry, biophysics and the surface sciences.Nanoparticle quantum optics is a growing field, which will intrigue researchers still for many years to come. This review can, therefore, only be a snapshot of a very dynamical process.
A Novel Method for Remote Depth Estimation of Buried Radioactive Contamination.
Ukaegbu, Ikechukwu Kevin; Gamage, Kelum A A
2018-02-08
Existing remote radioactive contamination depth estimation methods for buried radioactive wastes are either limited to less than 2 cm or are based on empirical models that require foreknowledge of the maximum penetrable depth of the contamination. These severely limits their usefulness in some real life subsurface contamination scenarios. Therefore, this work presents a novel remote depth estimation method that is based on an approximate three-dimensional linear attenuation model that exploits the benefits of using multiple measurements obtained from the surface of the material in which the contamination is buried using a radiation detector. Simulation results showed that the proposed method is able to detect the depth of caesium-137 and cobalt-60 contamination buried up to 40 cm in both sand and concrete. Furthermore, results from experiments show that the method is able to detect the depth of caesium-137 contamination buried up to 12 cm in sand. The lower maximum depth recorded in the experiment is due to limitations in the detector and the low activity of the caesium-137 source used. Nevertheless, both results demonstrate the superior capability of the proposed method compared to existing methods.
NASA Technical Reports Server (NTRS)
Fichtel, C. E.; Bertsch, D. L.; Dingus, B. L.; Esposito, J. A.; Hartman, R. C.; Hunter, S. D.; Kanbach, G.; Kniffen, D. A.; Lin, Y. C.; Mattox, J. R.
1994-01-01
Hawking (1974) and Page & Hawking (1976) investigated theoretically the possibility of detecting high-energy gamma rays produced by the quantum-mechanical decay of a small black hole created in the early universe. They concluded that, at the very end of the life of the small black hole, it would radiate a burst of gamma rays peaked near 250 MeV with a total energy of about 10(exp 34) ergs in the order of a microsecond or less. The characteristics of a black hole are determined by laws of physics beyond the range of current particle accelerators; hence, the search for these short bursts of high-energy gamma rays provides at least the possibility of being the first test of this region of physics. The Compton Observatory Energetic Gamma-Ray Experiment Telescope (EGRET) has the capability of detecting directly the gamma rays from such bursts at a much fainter level than SAS 2, and a search of the EGRET data has led to an upper limit of 5 x 10(exp -2) black hole decays per cu pc per yr, placing constraints on this and other theories predicting microsecond high-energy gamma-ray bursts.
A Novel Method for Remote Depth Estimation of Buried Radioactive Contamination
2018-01-01
Existing remote radioactive contamination depth estimation methods for buried radioactive wastes are either limited to less than 2 cm or are based on empirical models that require foreknowledge of the maximum penetrable depth of the contamination. These severely limits their usefulness in some real life subsurface contamination scenarios. Therefore, this work presents a novel remote depth estimation method that is based on an approximate three-dimensional linear attenuation model that exploits the benefits of using multiple measurements obtained from the surface of the material in which the contamination is buried using a radiation detector. Simulation results showed that the proposed method is able to detect the depth of caesium-137 and cobalt-60 contamination buried up to 40 cm in both sand and concrete. Furthermore, results from experiments show that the method is able to detect the depth of caesium-137 contamination buried up to 12 cm in sand. The lower maximum depth recorded in the experiment is due to limitations in the detector and the low activity of the caesium-137 source used. Nevertheless, both results demonstrate the superior capability of the proposed method compared to existing methods. PMID:29419759
The LUCIFER Project: Achievements and Near Future Prospects
NASA Astrophysics Data System (ADS)
Beeman, J. W.; Bellini, F.; Benetti, P.; Cardani, L.; Casali, N.; Chiesa, D.; Clemenza, M.; Dafinei, I.; Di Domizio, S.; Ferroni, F.; Gironi, L.; Giuliani, A.; Gotti, C.; Maino, M.; Nagorny, S. S.; Nisi, S.; Nones, C.; Pagnanini, L.; Pattavina, L.; Pessina, G.; Piperno, G.; Pirro, S.; Previtali, E.; Rusconi, C.; Schäffner, K.; Tomei, C.; Vignati, M.
2016-08-01
In the view of exploring the inverted hierarchy region future experiments investigating the neutrinoless double beta decay have to demand for detectors with excellent energy resolution and zero background in the energy region of interest. Cryogenic scintillating bolometers are very suitable detectors for this task since they provide particle discrimination: the simultaneous detection of the phonon and light signal allows us to identify the interacting type of particle and thus guarantees a suppression of α -induced backgrounds, the key-issue for next-generation tonne-scale bolometric experiments. The LUCIFER project aims at running the first array of enriched scintillating Zn^{ {82}}Se bolometers (total mass of about 8kg of ^{ {82}}Se) with a background level as low as 10^{ {-3}} counts/(keV kg y) in the energy region of interest. The main effort is currently focused on the finalization of the crystal growth procedure in order to achieve high quality Zn^{ {82}}Se crystals both in terms of radiopurity and bolometric properties. We present results from tests of such crystals operated at mK temperatures which demonstrate the excellent background rejection capabilities of this detection approach towards a background-free demonstrator experiment. Besides, the high purity of the enriched ^{ {82}}Se material allows us to establish the most stringent limits on the half-life of the double beta decay of ^{ {82}}Se on excited levels.
ERIC Educational Resources Information Center
Klompas, Michelle; Ross, Eleanor
2004-01-01
The purpose of the study was to investigate the life experiences of a group of South African adults who stutter and the impact of stuttering on their quality of life. Participants were 16 adults with a mean age of 28.9 and ranging from 20 to 59 years. Methods involved individual interviews designed to explore the life domains of education; social…
NASA Astrophysics Data System (ADS)
Steininger, H.
2018-04-01
ExoMars as one of the few life detection missions can be an example of how planetary protection and contamination control influence of the development of flight hardware. A few lessons learned can be drawn from the mission even before launch.
An implantable blood pressure and flow transmitter.
NASA Technical Reports Server (NTRS)
Rader, R. D.; Meehan, J. P.; Henriksen, J. K. C.
1973-01-01
A miniature totally implantable FM/FM telemetry system has been developed to simultaneously measure blood pressure and blood flow, thus providing an appreciation of the hemodynamics of the circulation to the entire body or to a particular organ. Developed for work with animal subjects, the telemetry system's transmission time is controlled by an RF signal that permits an operating life of several months. Pressure is detected by a miniature intravascular transducer and flow is detected by an extravascular interferometric ultrasonic technique. Both pressure and flow are calibrated prior to implanting. The pressure calibration can be checked after the implanting by cannulation; flow calibration can be verified only at the end of the experiment by determining the voltage output from the implanted sensing system as a function of several measured flow rates. The utility of this device has been established by its use in investigating canine renal circulation during exercise, emotional encounters, administration of drugs, and application of accelerative forces.
Dich, Nadya; Hansen, Åse Marie; Avlund, Kirsten; Lund, Rikke; Mortensen, Erik Lykke; Bruunsgaard, Helle; Rod, Naja Hulvej
2015-01-01
Previous research indicates that early life adversity may heighten stress reactivity and impair mechanisms for adaptive coping, suggesting that experience of stress in early life may also potentiate adults' physiological vulnerability to stress in later life. The study tested this hypothesis by investigating whether the experience of stressful events and circumstances (SEC) in childhood or adolescence amplified the effect of adulthood SEC on physiological dysregulation (allostatic load, AL) in later midlife. Observational data were used in the present study. Physiological functioning was measured in later midlife (participants' age ranged from 49 to 63 years). Both childhood/adolescence and adulthood SEC were reported retrospectively on the same occasion. Participants were 5309 Danish men and women from Copenhagen Aging and Midlife Biobank (CAMB). SEC included socioeconomic and family factors. The AL index was based on nine cardiovascular, metabolic, and immune biomarkers. Experience of SEC in both early life and adulthood independently predicted higher AL. In men, experience of SEC in early life also potentiated the effect of SEC in adulthood on AL. The results provide further insight into the mechanisms behind the "biological embedding" of childhood stress.
Experience matters: neurologists' perspectives on ALS patients' well-being.
Aho-Özhan, Helena E A; Böhm, Sarah; Keller, Jürgen; Dorst, Johannes; Uttner, Ingo; Ludolph, Albert C; Lulé, Dorothée
2017-04-01
Despite the fatal outcome and progressive loss of physical functioning in amyotrophic lateral sclerosis (ALS), many patients maintain contentment in life. It has been shown that non-professionals tend to underestimate the well-being of patients with ALS, but professionals' perspective is yet to be studied. In total, 105 neurologists with varying degrees of experience with ALS were included in an anonymous survey. They were asked to estimate the quality of life and depressiveness of ALS patients with artificial ventilation and nutrition. Physicians' estimations were compared with previously reported subjective ratings of ALS patients with life-prolonging measures. Neurologists with significant experience on ALS and palliative care were able to accurately estimate depressiveness and quality of life of ALS patients with life-prolonging measures. Less experienced neurologists' estimation differed more from patients' reports. Of all life-prolonging measures neurologists regarded invasive ventilation as the measure associated with lowest quality of life and highest depressiveness of the patients. Experienced neurologists as well as neurologists with experience in palliative care are able to better empathize with patients with a fatal illness such as ALS and support important decision processes.
Ishioka, Noriaki; Suzuki, Hiromi; Asashima, Makoto; Kamisaka, Seiichiro; Mogami, Yoshihiro; Ochiai, Toshimasa; Aizawa-Yano, Sachiko; Higashibata, Akira; Ando, Noboru; Nagase, Mutsumu; Ogawa, Shigeyuki; Shimazu, Toru; Fukui, Keiji; Fujimoto, Nobuyoshi
2004-03-01
Japan Aerospace Exploration Agency (JAXA) has developed a cell biology experiment facility (CBEF) and a clean bench (CB) as a common hardware in which life science experiments in the Japanese Experiment Module (JEM known as "Kibo") of the International Space Station (ISS) can be performed. The CBEF, a CO2 incubator with a turntable that provides variable gravity levels, is the basic hardware required to carry out the biological experiments using microorganisms, cells, tissues, small animals, plants, etc. The CB provides a closed aseptic operation area for life science and biotechnology experiments in Kibo. A phase contrast and fluorescence microscope is installed inside CB. The biological experiment units (BEU) are designed to run individual experiments using the CBEF and the CB. A plant experiment unit (PEU) and two cell experiment units (CEU type1 and type2) for the BEU have been developed.
ERIC Educational Resources Information Center
Gulec-Aslan, Yesim; Ozbey, Fidan; Yassibas, Ugur
2013-01-01
The purpose of the study is to describe the life experiences of a young man who has been diagnosed with Autism Spectrum Disorders (ASD) through a narrative research. In other words, our research aim is to investigate the nature of life and especially the social and school experiences of individual affected by this syndrome. Data were collected via…
Method for photon activation positron annihilation analysis
Akers, Douglas W.
2006-06-06
A non-destructive testing method comprises providing a specimen having at least one positron emitter therein; determining a threshold energy for activating the positron emitter; and determining whether a half-life of the positron emitter is less than a selected half-life. If the half-life of the positron emitter is greater than or equal to the selected half-life, then activating the positron emitter by bombarding the specimen with photons having energies greater than the threshold energy and detecting gamma rays produced by annihilation of positrons in the specimen. If the half-life of the positron emitter is less then the selected half-life, then alternately activating the positron emitter by bombarding the specimen with photons having energies greater then the threshold energy and detecting gamma rays produced by positron annihilation within the specimen.
THE FLUIDS AND COMBUSTION FACILITY: ENABLING THE EXPLORATION OF SPACE
NASA Technical Reports Server (NTRS)
Weiland, Karen J.; Gati, Frank G.; Hill, Myron E.; OMalley, Terence; Zurawski, Robert L.
2005-01-01
The Fluids and Combustion Facility (FCF) is an International Space Station facility designed to support physical and biological research as well as technology experiments in space. The FCF consists of two racks called the Combustion Integrated Rack (CIR) and the Fluids Integrated Rack (FIR). The capabilities of the CIR and the FIR and plans for their utilization will support the President s vision for space exploration. The CIR will accommodate physical research and technology experiments that address needs in the areas of spacecraft fire prevention, detection and suppression, incineration of solid wastes, and power generation. Initial experiments will provide data to support design decisions for exploration spacecraft. The CIR provides a large sealed chamber in a near-weightless environment. The chamber supports many simulated atmospheres including lunar or Martian environments. The FIR will accommodate experiments that address needs for advanced life support, power, propulsion, and spacecraft thermal control systems. The FIR can also serve as a platform for experiments that address human health and performance, medical technologies, and biological sciences. The FIR provides a large volume for payload hardware, reconfigurable diagnostics, customizable software, active rack-level vibration isolation, and data acquisition and management in a nearly uniform temperature environment.
The Fluids and Combustion Facility: Enabling the Exploration of Space
NASA Technical Reports Server (NTRS)
Weiland, Karen J.; Gati, Frank G.; Hill, Myron E.; O'Malley Terence F.; Zurawski, Robert L.
2005-01-01
The Fluids and Combustion Facility (FCF) is an International Space Station facility designed to support physical and biological research as well as technology experiments in space. The FCF consists of two racks called the Combustion Integrated Rack (CIR) and the Fluids Integrated Rack (FIR). The capabilities of the CIR and the FIR and plans for their utilization will support the President's vision for space exploration. The CIR will accommodate physical research and technology experiments that address needs in the areas of spacecraft fire prevention, detection and suppression, incineration of solid wastes, and power generation. Initial experiments will provide data to support design decisions for exploration spacecraft. The CIR provides a large sealed chamber in a near-weightless environment. The chamber supports many simulated atmospheres including lunar or Martian environments. The FIR will accommodate experiments that address needs for advanced life support, power, propulsion, and spacecraft thermal control systems. The FIR can also serve as a platform for experiments that address human health and performance, medical technologies, and biological sciences. The FIR provides a large volume for payload hardware, reconfigurable diagnostics, customizable software, active rack-level vibration isolation, and data acquisition and management in a nearly uniform temperature environment.
Age at adoption from institutional care as a window into the lasting effects of early experiences
Julian, Megan M.
2013-01-01
One of the major questions of human development is how early experience impacts the course of development years later. Children adopted from institutional care experience varying levels of deprivation in their early life followed by qualitatively better care in an adoptive home, providing a unique opportunity to study the lasting effects of early deprivation and its timing. The effects of age at adoption from institutional care are discussed for multiple domains of social and behavioral development within the context of several prominent developmental hypotheses about the effects of early deprivation (cumulative effects, experience-expectant developmental programming, and experience-adaptive developmental programming). Age at adoption effects are detected in a majority of studies, particularly when children experienced global deprivation and were assessed in adolescence. For most outcomes, institutionalization beyond a certain age is associated with a step-like increase in risk for lasting social and behavioral problems, with the step occurring at an earlier age for children who experienced more severe levels of deprivation. Findings are discussed in terms of their concordance and discordance with our current hypotheses, and speculative explanations for the findings are offered. PMID:23576122
The viking biological investigation: preliminary results.
Klein, H P; Horowitz, N H; Levin, G V; Oyama, V I; Lederberg, J; Rich, A; Hubbard, J S; Hobby, G L; Straat, P A; Berdahl, B J; Carle, G C; Brown, F S; Johnson, R D
1976-10-01
Three different types of biological experiments on samples of martian surface material ("soil") were conducted inside the Viking lander. In the carbon assimilation or pyrolytic release experiment, (14)CO(2) and (14)CO were exposed to soil in the presence of light. A small amount of gas was found to be converted into organic material. Heat treatment of a duplicate sample prevented such conversion. In the gas exchange experiment, soil was first humidified (exposed to water vapor) for 6 sols and then wet with a complex aqueous solution of metabolites. The gas above the soil was monitored by gas chromatography. A substantial amount of O(2) was detected in the first chromatogram taken 2.8 hours after humidification. Subsequent analyses revealed that significant increases in CO(2) and only small changes in N(2) had also occurred. In the labeled release experiment, soil was moistened with a solution containing several (14)C-labeled organic compounds. A substantial evolution of radioactive gas was registered but did not occur with a duplicate heat-treated sample. Alternative chemical and biological interpretations are possible for these preliminary data. The experiments are still in process, and these results so far do not allow a decision regarding the existence of life on the plonet Mars.
Boyes, Mark E; Hasking, Penelope A; Martin, Graham
2016-10-01
The current study tested whether emotion regulation and rumination moderated and/or mediated the relationship between accumulated adverse life experience and psychological distress in adolescence. In class, Australian high school students (n = 2637, 12-18 years, 68% female) from 41 schools completed well-validated measures of adverse life experience, emotion regulation, rumination and psychological distress, and were followed up 1 year later (n = 1973, 75% retention rate). Adjusting for age, gender and baseline psychological distress, adverse life experience predicted psychological distress 1 year later. Expressive suppression and rumination were positively associated with psychological distress. Cognitive reappraisal was negatively associated with psychological distress and moderated the relationship between adverse life experience and psychological distress. This relationship was also partially mediated by cognitive reappraisal, expressive suppression and rumination. Promoting cognitive reappraisal and minimizing expressive suppression and rumination may be useful strategies to improve mental health for adolescents who have experienced adverse life events. Future research should examine whether adolescents who have experienced adverse life events can be trained in effective emotion regulation strategies and whether this training can prevent development of psychological maladjustment. Copyright © 2015 John Wiley & Sons, Ltd. Copyright © 2015 John Wiley & Sons, Ltd.
Taghiabadi, Mina; Kavosi, Ali; Mirhafez, Seyed Reza; Keshvari, Mahrokh; Mehrabi, Tayebe
2017-01-01
Introduction Death anxiety is a concept with greater importance among the elderly as they approach inevitability of death. Identifying the correlates of death anxiety among old people is important in order to reduce the burden of this problem. Therefore, the present study was performed with the aim to examine the association between spiritual experiences and life satisfaction with death anxiety in this stage of life. Method This cross-sectional study with descriptive-analytical design included 190 elderly people visiting the health and medical centers of Neyshabur city, Iran, during fall and winter, 2016. Participants were asked to complete three questionnaires including a 16-item spiritual experiences scale, life satisfaction index proposed by Wood and Shifor with 13 items, and a 27-item death anxiety scale developed by Aminpour. Analytical statistics (Spearman’s correlation coefficient, Pearson’s correlation coefficient) were conducted using SPSS software version 22. Results Fifty-eight percent of participants were in younger elderly age group with mean age of 68.18±7.13 years and the number of men and women was the same (95). A significant positive association between spiritual experiences and life satisfaction (r=0.2, p<0.05), a significant negative association between spiritual experiences and death anxiety (r=−0.184, p< 0.05) and a significant negative relationship between life satisfaction and death anxiety (r=−0.2, p<0.05) was found. Conclusion Based on results, it seems that reducing stressors in this stage of life including reduction of death anxiety, is possible through use of spiritual experiences and increasing life satisfaction. PMID:28461873
The lived experience of engaging in everyday occupations in persons with mild to moderate aphasia.
Niemi, Tuuli; Johansson, Ulla
2013-10-01
Impairment of language ability, aphasia, can cause barriers to communication and hence impact on participation in many life situations. This study aimed to describe and explore how persons with aphasia following stroke experience engaging in everyday occupations. Six persons from Southwest Finland who had aphasia due to stroke one to four years previously were interviewed for the study. A modified form of the empirical phenomenological psychological method was used for data analysis. Three main characteristics of experiences of engaging in everyday occupations were identified: (1) encountering new experiences in everyday occupations, (2) striving to handle everyday occupations and (3) going ahead with life. The participants had experienced an altering life-world. Engagement in occupations affected their perceptions of competence and identity, and experiences of belonging and well-being. It was also through engagement in everyday occupations that they had discovered and learnt to handle changes in their everyday life. Aphasia can have a long-term impact on engagement in everyday occupations and participation in society, but conversely, engagement in meaningful occupations can also contribute to adaptation to disability and life changes. Aphasia can have a long-term impact on engagement in everyday occupations and participation in society. Health care professionals need to determine what clients with aphasia think about their occupations and life situations in spite of difficulties they may have verbalizing their thoughts. Experiences of engaging in meaningful occupations can help clients with aphasia in reconstructing their life stories, thereby contributing to adaptation to disability and life changes.
Lung ultrasound accurately detects pneumothorax in a preterm newborn lamb model.
Blank, Douglas A; Hooper, Stuart B; Binder-Heschl, Corinna; Kluckow, Martin; Gill, Andrew W; LaRosa, Domenic A; Inocencio, Ishmael M; Moxham, Alison; Rodgers, Karyn; Zahra, Valerie A; Davis, Peter G; Polglase, Graeme R
2016-06-01
Pneumothorax is a common emergency affecting extremely preterm. In adult studies, lung ultrasound has performed better than chest x-ray in the diagnosis of pneumothorax. The purpose of this study was to determine the efficacy of lung ultrasound (LUS) examination to detect pneumothorax using a preterm animal model. This was a prospective, observational study using newborn Border-Leicester lambs at gestational age = 126 days (equivalent to gestational age = 26 weeks in humans) receiving mechanical ventilation from birth to 2 h of life. At the conclusion of the experiment, LUS was performed, the lambs were then euthanised and a post-mortem exam was immediately performed. We used previously published ultrasound techniques to identify pneumothorax. Test characteristics of LUS to detect pneumothorax were calculated, using the post-mortem exam as the 'gold standard' test. Nine lambs (18 lungs) were examined. Four lambs had a unilateral pneumothorax, all of which were identified by LUS with no false positives. This was the first study to use post-mortem findings to test the efficacy of LUS to detect pneumothorax in a newborn animal model. Lung ultrasound accurately detected pneumothorax, verified by post-mortem exam, in premature, newborn lambs. © 2016 Paediatrics and Child Health Division (The Royal Australasian College of Physicians).
Single-trial lie detection using a combined fNIRS-polygraph system
Bhutta, M. Raheel; Hong, Melissa J.; Kim, Yun-Hee; Hong, Keum-Shik
2015-01-01
Deception is a human behavior that many people experience in daily life. It involves complex neuronal activities in addition to several physiological changes in the body. A polygraph, which can measure some of the physiological responses from the body, has been widely employed in lie-detection. Many researchers, however, believe that lie detection can become more precise if the neuronal changes that occur in the process of deception can be isolated and measured. In this study, we combine both measures (i.e., physiological and neuronal changes) for enhanced lie-detection. Specifically, to investigate the deception-related hemodynamic response, functional near-infrared spectroscopy (fNIRS) is applied at the prefrontal cortex besides a commercially available polygraph system. A mock crime scenario with a single-trial stimulus is set up as a deception protocol. The acquired data are classified into “true” and “lie” classes based on the fNIRS-based hemoglobin-concentration changes and polygraph-based physiological signal changes. Linear discriminant analysis is utilized as a classifier. The results indicate that the combined fNIRS-polygraph system delivers much higher classification accuracy than that of a singular system. This study demonstrates a plausible solution toward single-trial lie-detection by combining fNIRS and the polygraph. PMID:26082733
Hellman, Therese; Jonsson, Hans; Johansson, Ulla; Tham, Kerstin
2013-10-01
The aim was to describe and understand how connecting rehabilitation experiences and everyday life was characterised in the lived experiences during the rehabilitation in women with stress-related ill health. Five women were interviewed on three occasions during a rehabilitation programme and once 3 months later. Data were analysed using the Empirical, Phenomenological and Psychological method. The participants experienced connections between their rehabilitation and their previous, present and future everyday life influencing both rehabilitation and everyday life in a back-and-forth process. These connections were experienced in mind or in doing, mostly targeting the private arena in everyday life. Connecting rehabilitation experiences to their working situations was more challenging and feelings of frustration and being left alone were experienced. Although the participants described constructive connections between rehabilitation experiences and the private arena in everyday life, they mostly failed to experience connections that facilitated a positive return to work. Recommended support in the return to work process in rehabilitation comprises the provision of practical work-related activities during rehabilitation; being supportive in a constructive dialogue between the participant and the workplace, and continuing this support in follow-ups after the actual rehabilitation period. Rehabilitation for persons with stress-related ill health needs to focus on the private arena as well as the work situation in everyday life. Creative activities may enable experiences that inspire connections in mind and connections targeting the private arena in everyday life. The work situation needs to be thoroughly discussed during rehabilitation for enabling the participants to experience a support in the return to work process. Rehabilitation including practical work-related activities, support in a constructive dialogue between the participant and the manager at the workplace, and continued support in follow-ups targeting the workplace might be beneficial for successfully return to work.
NASA Astrophysics Data System (ADS)
Storrie-Lombardi, M. C.; Sattler, B.; Muller, J.-P.; Fisk, M.; Cousins, C.; Dartnell, L.
2009-04-01
Laser induced fluorescence imaging using excitation in ultraviolet (UV) wavelengths has been proposed as a nondestructive astrobiological rapid survey tool to search for amino and nucleic acids [1], microbial life [2], and polycyclic aromatic hydrocarbons (PAHs) deep in the Mars regolith [3, 4]. However, the technique is easily adapted to search for complex biomolecular targets using longer wavelength sources [5]. Of particular interest is the ability of excitation at 532 nm to detect photosynthetic pigments in cyanobacteria-dominated microbial communities populating the ice of alpine, Arctic, and Antarctic lakes, glaciers, and ice sheets [6-8]. During the months of November and December 2008 we tested the technique as part of an extended international, interdisciplinary field campaign in the Dry Valleys of Schirmacher Oasis and Lake Untersee, Queen Maud Land, Antarctica. In this paper we review our recent laboratory experiments on the use of UV excitation for detection of PAHs doped on Mars analogue soils [9] and chasmo- and epilithic lichen communities within basaltic Iceland lavas. We present for the first time the results of our field experiments conducted during the Tawani 2008 International Antarctic Expedition for in situ detection and quantification of photosynthetic biomass in the ice caps of annual and perennially ice-covered Antarctic lakes. We discuss the advantages of using a nondestructive rapid survey photonic tools such as laser induced fluorescence imaging that can be easily implemented from lander, rover, airborne, or orbital platforms. The techniques presented can be utilized to monitor the microbial potential of large, critical ecosystems on Earth, or to facilitate the remote or manned search for organics and photosynthetic life on any terrestrial planet. References 1. Storrie-Lombardi, M.C., Hug, W.F., McDonald, G.D., Tsapin, A.I., and Nealson, K.H. 2001. Hollow cathode ion lasers for deep ultraviolet Raman spectroscopy and fluorescence imaging. Rev. Sci. Ins., 72(12): 4452-4459. 2. Nealson, K.H., Tsapin, A., and Storrie-Lombardi, M. 2002. Searching for life in the universe: unconventional methods for an unconventional problem. International Microbio., 5: 223-230. 3. Storrie-Lombardi, M.C., Muller, J.-P., Fisk, M.R., Griffiths, A.D., and Coates, A.J. 2008a. Potential for non-destructive astrochemistry using the ExoMars PanCam. Geophys. Res. Lett., 35: L12201, doi 10.1029/2008GL034296. 4. Storrie-Lombardi, M.C., Muller, J.-P., Fisk, M.R., Griffiths, A.D., and Coates, A.J. 2008b. Epifluorescence surveys of extreme environments using PanCam imaging systems: Antarctica and the Mars regolith. Instruments, Methods, and Missions for Astrobiology XI (R.B. Hoover, G.V. Levin, & A.Y. Rozanov, Eds.) Proc. SPIE, 7097 (25): 1-10. 5. Storrie-Lombardi, M.C. 2005. Post-Bayesian strategies to optimize astrobiology instrument suites: lessons from Antarctica and the Pilbara. Astrobiology and Planetary Missions (R. B. Hoover, G. V. Levin and A. Y. Rozanov, Eds.), Proc. SPIE, 5906: 288-301. 6. Psenner, R. and Sattler, B. 1998. Life at the freezing point. Science, 280: 2073-2074. 7. Sattler, B., Puxbaum, H., and Psenner, R. 2001. Bacterial growth in supercooled cloud droplets. Geophys. Res. Ltrs., 28(2): 239-242. 8. Sattler, B., Waldhuber, S., Fischer, H., Semmler, H., Sipiera, P., and Psenner, R. 2004. Microbial activity and phylogeny in ice cores retrieved from Lake Paula, a newly detected freshwater lake in Antarctica. Instruments, Methods, and Missions for Astrobiology VIII (R. B. Hoover, G. V. Levin and A. Y. Rozanov, Eds.) Proc. SPIE, 5555: 170-179. 9. Muller, J.-P., Storrie-Lombardi, M.C., Fisk, M.R., Coates, A., Griffiths, A., Rees, K., Walton, D., Theobald, C., Brockley-Blatt, C., and Rousseau, A. 2009. WALI - Wide Angle Laser Imaging enhancement to ExoMars PanCam: a system for organics and life detection in European Geosciences Union General Assembly 2009. Vienna, Austria.
At what age is hydrocephalus detected, and what is the role of head circumference measurements?
Breuning-Broers, Jacqueline M; Deurloo, Jacqueline A; Gooskens, Rob H; Verkerk, Paul H
2014-02-01
To investigate at what age hydrocephalus is detected and to assess the role of head circumference measurements in detecting hydrocephalus, we performed a retrospective chart review in children with hydrocephalus treated in a tertiary paediatric hospital in the Netherlands. The study group contained 146 patients; 38 patients (31%) were referred because of abnormalities in head circumference. Eighty-nine per cent of the patients were detected in the first year of life. After this period, no patients were referred because of an abnormal head circumference. Therefore, head circumference measurements seem to have little value for detecting hydrocephalus after the first year of life.
Zanchetta, Margareth Santos; Cognet, Marguerite; Lam-Kin-Teng, Mary Rachel; Dumitriu, Marie Elisabeth; Renaud, Lise; Rhéaume, Jacques
2016-12-16
Survivors' testimonies can reveal much about men's experiences of prostate cancer and impacts on their quality of life (QOL) during the clinical trajectory of the disease. These survivors' shared thoughts and views were hypothesized to reflect salient features of their lived social representation of prostate cancer. We explored the content of testimonies posted by men to a public blog hosted by a French national prostate cancer patients' association. The study question, "What do French bloggers' testimonies reveal about their lived experiences with prostate cancer, especially regarding their quality of life in community settings, that underpin their social representation of prostate cancer?" guided the exploration and analysis of the textual data. The aims were to better understand men's experiences and predominant thoughts and views, to elucidate patients' behaviours, and to enlighten medical policy and practice. Explore issues of QOL as reported by French prostate cancer survivors in a public blog by: (a) identifying the salient aspects and issues of the experience of living with prostate cancer from the perspective of survivors; and (b) analyzing the content in the posted testimonies regarding perceived and lived impacts of prostate cancer on QOL. A critical ethnographic study guided the selection of textual data from 196 male bloggers' testimonies about prostate cancer posted in the period from 2008 to 2013. Media content analysis method was undertaken on blog testimonies, framed by a multidimensional conceptual framework of QOL. Testimonies focused mainly on medical care and rehabilitation, recovery, health education and self-care, as well as on a global vision of prostate cancer and its impacts on personal views of manhood and masculinity. The language used indicated that political, educative and compassionate discourses were intertwined to create a complex representation of the experience and effects of prostate cancer; this multi-faceted representation can inform the public and professional debate about men's capacity to provide emotional support and problem-solve within a community of interest. Findings, while based on data limited to mostly one-time entries to a French blog, contribute to understanding a unique, collective expression of men's lived experiences of prostate cancer. These anonymous survivors shared their varied reactions, ways of coping, and thoughts on needed change.
The most conserved genome segments for life detection on Earth and other planets.
Isenbarger, Thomas A; Carr, Christopher E; Johnson, Sarah Stewart; Finney, Michael; Church, George M; Gilbert, Walter; Zuber, Maria T; Ruvkun, Gary
2008-12-01
On Earth, very simple but powerful methods to detect and classify broad taxa of life by the polymerase chain reaction (PCR) are now standard practice. Using DNA primers corresponding to the 16S ribosomal RNA gene, one can survey a sample from any environment for its microbial inhabitants. Due to massive meteoritic exchange between Earth and Mars (as well as other planets), a reasonable case can be made for life on Mars or other planets to be related to life on Earth. In this case, the supremely sensitive technologies used to study life on Earth, including in extreme environments, can be applied to the search for life on other planets. Though the 16S gene has become the standard for life detection on Earth, no genome comparisons have established that the ribosomal genes are, in fact, the most conserved DNA segments across the kingdoms of life. We present here a computational comparison of full genomes from 13 diverse organisms from the Archaea, Bacteria, and Eucarya to identify genetic sequences conserved across the widest divisions of life. Our results identify the 16S and 23S ribosomal RNA genes as well as other universally conserved nucleotide sequences in genes encoding particular classes of transfer RNAs and within the nucleotide binding domains of ABC transporters as the most conserved DNA sequence segments across phylogeny. This set of sequences defines a core set of DNA regions that have changed the least over billions of years of evolution and provides a means to identify and classify divergent life, including ancestrally related life on other planets.
NASA Astrophysics Data System (ADS)
2012-04-01
European Southern Observatory data from the Very Large Telescope have enabled astronomers to say with confidence that they can detect signs of life on Earth using spectropolarimetry of earthshine: light from the Earth's atmosphere reflected from the Moon. This is an important step towards detecting life on exoplanets. A collection of archive materials from the family of Sir John F W Herschel (1792-1871) is now available for study at Harry Ransom Center at the University of Texas at Austin. The collection includes much of John Herschel's correspondence as well as examples of his cyanotypes.
Guo, Hansong; Huang, He; Huang, Liusheng; Sun, Yu-E
2016-01-01
As the size of smartphone touchscreens has become larger and larger in recent years, operability with a single hand is getting worse, especially for female users. We envision that user experience can be significantly improved if smartphones are able to recognize the current operating hand, detect the hand-changing process and then adjust the user interfaces subsequently. In this paper, we proposed, implemented and evaluated two novel systems. The first one leverages the user-generated touchscreen traces to recognize the current operating hand, and the second one utilizes the accelerometer and gyroscope data of all kinds of activities in the user’s daily life to detect the hand-changing process. These two systems are based on two supervised classifiers constructed from a series of refined touchscreen trace, accelerometer and gyroscope features. As opposed to existing solutions that all require users to select the current operating hand or confirm the hand-changing process manually, our systems follow much more convenient and practical methods and allow users to change the operating hand frequently without any harm to the user experience. We conduct extensive experiments on Samsung Galaxy S4 smartphones, and the evaluation results demonstrate that our proposed systems can recognize the current operating hand and detect the hand-changing process with 94.1% and 93.9% precision and 94.1% and 93.7% True Positive Rates (TPR) respectively, when deciding with a single touchscreen trace or accelerometer-gyroscope data segment, and the False Positive Rates (FPR) are as low as 2.6% and 0.7% accordingly. These two systems can either work completely independently and achieve pretty high accuracies or work jointly to further improve the recognition accuracy. PMID:27556461
Guo, Hansong; Huang, He; Huang, Liusheng; Sun, Yu-E
2016-08-20
As the size of smartphone touchscreens has become larger and larger in recent years, operability with a single hand is getting worse, especially for female users. We envision that user experience can be significantly improved if smartphones are able to recognize the current operating hand, detect the hand-changing process and then adjust the user interfaces subsequently. In this paper, we proposed, implemented and evaluated two novel systems. The first one leverages the user-generated touchscreen traces to recognize the current operating hand, and the second one utilizes the accelerometer and gyroscope data of all kinds of activities in the user's daily life to detect the hand-changing process. These two systems are based on two supervised classifiers constructed from a series of refined touchscreen trace, accelerometer and gyroscope features. As opposed to existing solutions that all require users to select the current operating hand or confirm the hand-changing process manually, our systems follow much more convenient and practical methods and allow users to change the operating hand frequently without any harm to the user experience. We conduct extensive experiments on Samsung Galaxy S4 smartphones, and the evaluation results demonstrate that our proposed systems can recognize the current operating hand and detect the hand-changing process with 94.1% and 93.9% precision and 94.1% and 93.7% True Positive Rates (TPR) respectively, when deciding with a single touchscreen trace or accelerometer-gyroscope data segment, and the False Positive Rates (FPR) are as low as 2.6% and 0.7% accordingly. These two systems can either work completely independently and achieve pretty high accuracies or work jointly to further improve the recognition accuracy.
Kangas, M; Vikman, I; Nyberg, L; Korpelainen, R; Lindblom, J; Jämsä, T
2012-03-01
Falling is a common accident among older people. Automatic fall detectors are one method of improving security. However, in most cases, fall detectors are designed and tested with data from experimental falls in younger people. This study is one of the first to provide fall-related acceleration data obtained from real-life falls. Wireless sensors were used to collect acceleration data during a six-month test period in older people. Data from five events representing forward falls, a sideways fall, a backwards fall, and a fall out of bed were collected and compared with experimental falls performed by middle-aged test subjects. The signals from real-life falls had similar features to those from intentional falls. Real-life forward, sideways and backward falls all showed a pre impact phase and an impact phase that were in keeping with the model that was based on experimental falls. In addition, the fall out of bed had a similar acceleration profile as the experimental falls of the same type. However, there were differences in the parameters that were used for the detection of the fall phases. The beginning of the fall was detected in all of the real-life falls starting from a standing posture, whereas the high pre impact velocity was not. In some real-life falls, multiple impacts suggested protective actions. In conclusion, this study demonstrated similarities between real-life falls of older people and experimental falls of middle-aged subjects. However, some fall characteristics detected from experimental falls were not detectable in acceleration signals from corresponding heterogeneous real-life falls. Copyright © 2011 Elsevier B.V. All rights reserved.
Rix, Catherine S; Sims, Mark R; Cullen, David C
2011-11-01
The proposed ExoMars mission, due to launch in 2018, aims to look for evidence of extant and extinct life in martian rocks and regolith. Previous attempts to detect organic molecules of biological or abiotic origin on Mars have been unsuccessful, which may be attributable to destruction of these molecules by perchlorate salts during pyrolysis sample extraction techniques. Organic molecules can also be extracted and measured with solvent-based systems. The ExoMars payload includes the Life Marker Chip (LMC) instrument, capable of detecting biomarker molecules of extant and extinct Earth-like life in liquid extracts of martian samples with an antibody microarray assay. The aim of the work reported here was to investigate whether the presence of perchlorate salts, at levels similar to those at the NASA Phoenix landing site, would compromise the LMC extraction and detection method. To test this, we implemented an LMC-representative sample extraction process with an LMC-representative antibody assay and used these to extract and analyze a model sample that consisted of a Mars analog sample matrix (JSC Mars-1) spiked with a representative organic molecular target (pyrene, an example of abiotic meteoritic infall targets) in the presence of perchlorate salts. We found no significant change in immunoassay function when using pyrene standards with added perchlorate salts. When model samples spiked with perchlorate salts were subjected to an LMC-representative liquid extraction, immunoassays functioned in a liquid extract and detected extracted pyrene. For the same model sample matrix without perchlorate salts, we observed anomalous assay signals that coincided with yellow coloration of the extracts. This unexpected observation is being studied further. This initial study indicates that the presence of perchlorate salts, at levels similar to those detected at the NASA Phoenix landing site, is unlikely to prevent the LMC from extracting and detecting organic molecules from martian samples.
Determination of Geochemical Bio-Signatures in Mars-Like Basaltic Environments
Olsson-Francis, Karen; Pearson, Victoria K.; Steer, Elisabeth D.; Schwenzer, Susanne P.
2017-01-01
Bio-signatures play a central role in determining whether life existed on early Mars. Using a terrestrial basalt as a compositional analog for the martian surface, we applied a combination of experimental microbiology and thermochemical modeling techniques to identify potential geochemical bio-signatures for life on early Mars. Laboratory experiments were used to determine the short-term effects of biota on the dissolution of terrestrial basalt, and the formation of secondary alteration minerals. The chemoorganoheterotrophic bacterium, Burkholderia sp. strain B_33, was grown in a minimal growth medium with and without terrestrial basalt as the sole nutrient source. No growth was detected in the absence of the basalt. In the presence of basalt, during exponential growth, the pH decreased rapidly from pH 7.0 to 3.6 and then gradually increased to a steady-state of equilibrium of between 6.8 and 7.1. Microbial growth coincided with an increase in key elements in the growth medium (Si, K, Ca, Mg, and Fe). Experimental results were compared with theoretical thermochemical modeling to predict growth of secondary alteration minerals, which can be used as bio-signatures, over a geological timescale. We thermochemically modeled the dissolution of the basalt (in the absence of biota) in very dilute brine at 25°C, 1 bar; the pH was buffered by the mineral dissolution and precipitation reactions. Preliminary results suggested that at the water to rock ratio of 1 × 107, zeolite, hematite, chlorite, kaolinite, and apatite formed abiotically. The biotic weathering processes were modeled by varying the pH conditions within the model to adjust for biologic influence. The results suggested that, for a basaltic system, the microbially-mediated dissolution of basalt would result in “simpler” secondary alteration, consisting of Fe-hydroxide and kaolinite, under conditions where the abiotic system would also form chlorite. The results from this study demonstrate that, by using laboratory-based experiments and thermochemical modeling, it is possible to identify secondary alteration minerals that could potentially be used to distinguish between abiotic and biotic weathering processes on early Mars. This work will contribute to the interpretation of data from past, present, and future life detection missions to Mars. PMID:28943863
Determination of Geochemical Bio-Signatures in Mars-Like Basaltic Environments.
Olsson-Francis, Karen; Pearson, Victoria K; Steer, Elisabeth D; Schwenzer, Susanne P
2017-01-01
Bio-signatures play a central role in determining whether life existed on early Mars. Using a terrestrial basalt as a compositional analog for the martian surface, we applied a combination of experimental microbiology and thermochemical modeling techniques to identify potential geochemical bio-signatures for life on early Mars. Laboratory experiments were used to determine the short-term effects of biota on the dissolution of terrestrial basalt, and the formation of secondary alteration minerals. The chemoorganoheterotrophic bacterium, Burkholderia sp. strain B_33, was grown in a minimal growth medium with and without terrestrial basalt as the sole nutrient source. No growth was detected in the absence of the basalt. In the presence of basalt, during exponential growth, the pH decreased rapidly from pH 7.0 to 3.6 and then gradually increased to a steady-state of equilibrium of between 6.8 and 7.1. Microbial growth coincided with an increase in key elements in the growth medium (Si, K, Ca, Mg, and Fe). Experimental results were compared with theoretical thermochemical modeling to predict growth of secondary alteration minerals, which can be used as bio-signatures, over a geological timescale. We thermochemically modeled the dissolution of the basalt (in the absence of biota) in very dilute brine at 25°C, 1 bar; the pH was buffered by the mineral dissolution and precipitation reactions. Preliminary results suggested that at the water to rock ratio of 1 × 10 7 , zeolite, hematite, chlorite, kaolinite, and apatite formed abiotically. The biotic weathering processes were modeled by varying the pH conditions within the model to adjust for biologic influence. The results suggested that, for a basaltic system, the microbially-mediated dissolution of basalt would result in "simpler" secondary alteration, consisting of Fe-hydroxide and kaolinite, under conditions where the abiotic system would also form chlorite. The results from this study demonstrate that, by using laboratory-based experiments and thermochemical modeling, it is possible to identify secondary alteration minerals that could potentially be used to distinguish between abiotic and biotic weathering processes on early Mars. This work will contribute to the interpretation of data from past, present, and future life detection missions to Mars.
Planetary protection implementation on future Mars lander missions
NASA Astrophysics Data System (ADS)
Howell, Robert; Devincenzi, Donald L.
1993-06-01
A workshop was convened to discuss the subject of planetary protection implementation for Mars lander missions. It was sponsored and organized by the Exobiology Implementation Team of the U.S./Russian Joint Working Group on Space Biomedical and Life Support Systems. The objective of the workshop was to discuss planetary protection issues for the Russian Mars '94 mission, which is currently under development, as well as for additional future Mars lander missions including the planned Mars '96 and U.S. MESUR Pathfinder and Network missions. A series of invited presentations was made to ensure that workshop participants had access to information relevant to the planned discussions. The topics summarized in this report include exobiology science objectives for Mars exploration, current international policy on planetary protection, planetary protection requirements developed for earlier missions, mission plans and designs for future U.S. and Russian Mars landers, biological contamination of spacecraft components, and techniques for spacecraft bioload reduction. In addition, the recent recommendations of the U.S. Space Studies Board (SSB) on this subject were also summarized. Much of the discussion focused on the recommendations of the SSB. The SSB proposed relaxing the planetary protection requirements for those Mars lander missions that do not contain life detection experiments, but maintaining Viking-like requirements for those missions that do contain life detection experiments. The SSB recommendations were found to be acceptable as a guide for future missions, although many questions and concerns about interpretation were raised and are summarized. Significant among the concerns was the need for more quantitative guidelines to prevent misinterpretation by project offices and better access to and use of the Viking data base of bio-assays to specify microbial burden targets. Among the questions raised were how will the SSB recommendations be integrated with existing Committee on Space Research (COSPAR) policy and how will they apply to and affect Mars '94, Mars '96, MESUR Pathfinder, and MESUR Network missions? One additional topic briefly considered at the workshop was the identification of some issues related to planetary protection considerations for Mars sample return missions. These issues will form the basis for a follow-on joint U.S./Russian workshop on that subject.
Planetary protection implementation on future Mars lander missions
NASA Technical Reports Server (NTRS)
Howell, Robert; Devincenzi, Donald L.
1993-01-01
A workshop was convened to discuss the subject of planetary protection implementation for Mars lander missions. It was sponsored and organized by the Exobiology Implementation Team of the U.S./Russian Joint Working Group on Space Biomedical and Life Support Systems. The objective of the workshop was to discuss planetary protection issues for the Russian Mars '94 mission, which is currently under development, as well as for additional future Mars lander missions including the planned Mars '96 and U.S. MESUR Pathfinder and Network missions. A series of invited presentations was made to ensure that workshop participants had access to information relevant to the planned discussions. The topics summarized in this report include exobiology science objectives for Mars exploration, current international policy on planetary protection, planetary protection requirements developed for earlier missions, mission plans and designs for future U.S. and Russian Mars landers, biological contamination of spacecraft components, and techniques for spacecraft bioload reduction. In addition, the recent recommendations of the U.S. Space Studies Board (SSB) on this subject were also summarized. Much of the discussion focused on the recommendations of the SSB. The SSB proposed relaxing the planetary protection requirements for those Mars lander missions that do not contain life detection experiments, but maintaining Viking-like requirements for those missions that do contain life detection experiments. The SSB recommendations were found to be acceptable as a guide for future missions, although many questions and concerns about interpretation were raised and are summarized. Significant among the concerns was the need for more quantitative guidelines to prevent misinterpretation by project offices and better access to and use of the Viking data base of bioassays to specify microbial burden targets. Among the questions raised were how will the SSB recommendations be integrated with existing Committee on Space Research (COSPAR) policy and how will they apply to and affect Mars '94, Mars '96, MESUR Pathfinder, and MESUR Network missions? One additional topic briefly considered at the workshop was the identification of some issues related to planetary protection considerations for Mars sample return missions. These issues will form the basis for a follow-on joint U.S./Russian workshop on that subject.
Work-family interface from a life and career stage perspective: the role of demands and resources.
Demerouti, Evangelia; Peeters, Maria C W; van der Heijden, Beatrice I J M
2012-01-01
Work-family conflict and enrichment are experiences that occur daily and have substantial consequences for employees, their families, and the organizations that employ them. The aim of the current review is to make a link between life and career stage, work and family conditions, and the work-family interface. The basic proposition is that life stages partly determine career development, and consequently the specific working conditions (job demands and job resources) and family conditions (family demands and family resources) that individuals are exposed to. As a result, the specific demands and resources in the work and family domains determine to what extent individuals experience that work and family are conflicting or enriching life domains. In this review we suggest that individuals in early adulthood will experience high inter-role conflict and low facilitation due to high demands and low resources in both life domains, while individuals in late adulthood will experience the opposite pattern; that is, low conflict and high facilitation due to low demands and high resources in both domains. Individuals in middle adulthood will experience high work-family conflict but also high family-work facilitation due to the presence of high job demands and resources in both life domains. Integrating life and career stage perspectives and the experience of work-family interface is of notable practical utility because it provides a mechanism to make more informed decisions about the relative need for and corresponding benefits of work-family programs.
Hansen, Lissi; Rosenkranz, Susan J; Vaccaro, Gina M; Chang, Michael F
2015-01-01
In the United States, the incidence of hepatocellular carcinoma (HCC) is rising. For those diagnosed with terminal HCC, there is no curative treatment and duration of survival is typically 1 to 2 years. Research on illness and treatment experiences toward the end of life for patients with terminal HCC is limited. The aim of this study was to explore the illness experiences of patients with terminal HCC as they approached the end of life. This study used a prospective, longitudinal descriptive design. Interview data were collected from 14 patients once a month for up to 6 months, for a total of 45 interviews. Data were analyzed using conventional content analysis. Three major themes (illness perceptions, decision to start treatment, and navigating treatment over time) and 10 subthemes were identified that were reflected across time in all patient experiences. Patients faced challenges with symptom experiences, treatment decisions, and unmet information needs affecting their quality of life. Gaining knowledge about the challenges facing patients with HCC is crucial for designing interventions that optimize their quality of life. Healthcare professionals may improve the quality of life of patients with terminal HCC by eliciting patients' perceptions of their illness and treatment decisions, symptom experiences, and information needs as the disease progresses and providing symptom management and offering information tailored to their needs. Care for patients with HCC who are approaching the end of life should be multidisciplinary and include timely referral to palliative care.
Exploration of life experiences of positive growth in long-term childhood cancer survivors.
Kim, Yoonjung
2017-10-01
The aim of this study was to explore experiences of positive growth in long-term childhood cancer survivors, from their perspective. Fifteen long-term survivors of childhood cancer provided descriptions of their experiences. Data were collected through face-to-face interviews and the analysis was based on Giorgi's phenomenological research method. The analysis of positive growth experienced by long-term childhood cancer survivors revealed three themes: self-directed life, normalcy in life, and inner maturity. Long-term survivors defined positive growth as a successful transition to a self-satisfactory life based on motivation acquired through their cancer experience and on subjective goal-setting, as well as becoming cancer-free and living a normal life within society. They seemed to have acquired optimistic, flexible, active attitudes toward life while demonstrating profound gratefulness and consideration of people around them, as well as prudent approaches to health. The findings of this study verified that long-term survivors of childhood cancer have grown positively due to their negative past experience. We expect these findings to contribute to the development of programs that promote positive growth in long-term childhood cancer survivors. Copyright © 2017 Elsevier Ltd. All rights reserved.
Finding a Life Worth Living: Meaning in Life and Graduation from College.
Wilt, Joshua; Bleidorn, Wiebke; Revelle, William
2016-01-01
Graduation from college is an important milestone for young adults, marked by mixed emotions and poignancy, and therefore is an especially salient context for studying meaning in life. The present research used experience-sampling methodology to examine the antecedents and consequences of students' experience of meaning in life over the course of graduation. Participants were 74 graduating students who provided a total of 538 reports over the span of three days, including commencement day. Increased levels of state meaning in life during the days around commencement were linked to spending time with people in general and with family in particular, as well as thinking about one's years in college. Thinking about one's years in college mediated the effects of present company on state meaning in life. Graduates who experienced higher levels of state meaning in life during the days around their commencement ceremony had higher trait levels of meaning in life one week following commencement. We discuss how making meaning of a poignant experience has implications for healthy psychological development.
Limit on the radiative neutrinoless double electron capture of ^{36}Ar from GERDA Phase I
NASA Astrophysics Data System (ADS)
Agostini, M.; Allardt, M.; Bakalyarov, A. M.; Balata, M.; Barabanov, I.; Barros, N.; Baudis, L.; Bauer, C.; Bellotti, E.; Belogurov, S.; Belyaev, S. T.; Benato, G.; Bettini, A.; Bezrukov, L.; Bode, T.; Borowicz, D.; Brudanin, V.; Brugnera, R.; Caldwell, A.; Cattadori, C.; Chernogorov, A.; D'Andrea, V.; Demidova, E. V.; di Vacri, A.; Domula, A.; Doroshkevich, E.; Egorov, V.; Falkenstein, R.; Fedorova, O.; Freund, K.; Frodyma, N.; Gangapshev, A.; Garfagnini, A.; Gooch, C.; Grabmayr, P.; Gurentsov, V.; Gusev, K.; Hakenmüller, J.; Hegai, A.; Heisel, M.; Hemmer, S.; Heusser, G.; Hofmann, W.; Hult, M.; Inzhechik, L. V.; Csáthy, J. Janicskó; Jochum, J.; Junker, M.; Kazalov, V.; Kihm, T.; Kirpichnikov, I. V.; Kirsch, A.; Kish, A.; Klimenko, A.; Kneißl, R.; Knöpfle, K. T.; Kochetov, O.; Kornoukhov, V. N.; Kuzminov, V. V.; Laubenstein, M.; Lazzaro, A.; Lebedev, V. I.; Lehnert, B.; Liao, H. Y.; Lindner, M.; Lippi, I.; Lubashevskiy, A.; Lubsandorzhiev, B.; Lutter, G.; Macolino, C.; Majorovits, B.; Maneschg, W.; Medinaceli, E.; Miloradovic, M.; Mingazheva, R.; Misiaszek, M.; Moseev, P.; Nemchenok, I.; Palioselitis, D.; Panas, K.; Pandola, L.; Pelczar, K.; Pullia, A.; Riboldi, S.; Rumyantseva, N.; Sada, C.; Salamida, F.; Salathe, M.; Schmitt, C.; Schneider, B.; Schönert, S.; Schreiner, J.; Schütz, A.-K.; Schulz, O.; Schwingenheuer, B.; Selivanenko, O.; Shirchenko, M.; Simgen, H.; Smolnikov, A.; Stanco, L.; Stepaniuk, M.; Vanhoefer, L.; Vasenko, A. A.; Veresnikova, A.; von Sturm, K.; Wagner, V.; Walter, M.; Wegmann, A.; Wester, T.; Wiesinger, C.; Wilsenach, H.; Wojcik, M.; Yanovich, E.; Zhitnikov, I.; Zhukov, S. V.; Zinatulina, D.; Zuber, K.; Zuzel, G.
2016-12-01
Neutrinoless double electron capture is a process that, if detected, would give evidence of lepton number violation and the Majorana nature of neutrinos. A search for neutrinoless double electron capture of ^{36}Ar has been performed with germanium detectors installed in liquid argon using data from Phase I of the GERmanium Detector Array ( Gerda) experiment at the Gran Sasso Laboratory of INFN, Italy. No signal was observed and an experimental lower limit on the half-life of the radiative neutrinoless double electron capture of ^{36}Ar was established: T_{1/2} > 3.6 × 10^{21} years at 90% CI.
Limit on the radiative neutrinoless double electron capture of 36Ar from GERDA Phase I
Agostini, M.; Allardt, M.; Bakalyarov, A. M.; ...
2016-11-28
Neutrinoless double electron capture is a process that, if detected, would give evidence of lepton number violation and the Majorana nature of neutrinos. Here, a search for neutrinoless double electron capture of 36Ar has been performed with germanium detectors installed in liquid argon using data from Phase I of the GERmanium Detector Array (Gerda) experiment at the Gran Sasso Laboratory of INFN, Italy. No signal was observed and an experimental lower limit on the half-life of the radiative neutrinoless double electron capture of 36 Ar was established: T 1/2 > 3.6 × 10 21 years at 90% CI.
Nondestructive Testing Residual Stress Using Ultrasonic Critical Refracted Longitudinal Wave
NASA Astrophysics Data System (ADS)
Xu, Chunguang; Song, Wentao; Pan, Qinxue; Li, Huanxin; Liu, Shuai
Residual stress has significant impacts on the performance of the mechanical components, especially on its strength, fatigue life and corrosion resistance and dimensional stability. Based on theory of acoustoelasticity, the testing principle of ultrasonic LCR wave method is analyzed. The testing system of residual stress is build. The method of calibration of stress coefficient is proposed in order to improve the detection precision. At last, through experiments and applications on residual stress testing of oil pipeline weld joint, vehicle's torsion shaft, glass and ceramics, gear tooth root, and so on, the result show that it deserved to be studied deeply on application and popularization of ultrasonic LCR wave method.
Detecting Traces of Life in the Plume of Enceladus
NASA Astrophysics Data System (ADS)
Krolikowski, Daniel M.; Lunine, Jonathan I.
2015-01-01
Saturn's moon Enceladus presents one of the most promising bodies in the solar system on which to detect (at least traces of) extraterrestrial life. We present a study of biomarkers in the plume. A variety of potential biomarkers were considered and their applicability to the plume was assessed. Our study focused primarily on the relative abundances of hydrocarbons to methane, and amino acids. Concentrations of these biomarkers were estimated by combining data from studies of methanogenic and hydrothermal communities with a plume density model. We studied mass spectrometry as a possible means to detect these indicators of life. We performed a parameterized study by considering mass spectrometers with a sensitivity of 10, 100, and 1000 times that of Cassini's mass spectrometer. Promisingly, the concentration of biogenic hydrocarbons is around an order of magnitude higher than the detection threshold of the most sensitive mass spectrometer we considered. Therefore, analysis of such hydrocarbons on a future mission is a promising approach to detecting biochemical processes within Enceladus.
Growing Up Latino: Memoirs and Stories. Reflections on Life in the United States.
ERIC Educational Resources Information Center
Augenbraum, Harold, Ed.; Stavans, Ilan, Ed.
This anthology contains autobiographical and fictional short stories and excerpts from longer works by Hispanic-American authors about coming of age. Selections include reflections on Hispanic immigrant life in the United States, family life and relationships, school experiences, sexuality, Catholicism, identity formation, first experiences with…
Gregg, Jacob L.; Grady, Courtney A.; Thompson, Rachel L.; Purcell, Maureen K.; Friedman, Carolyn S.; Hershberger, Paul K.
2014-01-01
A combination of field surveys, molecular typing, and laboratory experiments were used to improve our understanding of the distribution and transmission mechanisms of fish parasites in the genus Ichthyophonus. Ichthyophonus spp. infections were detected from the Bering Sea to the coast of Oregon in 10 of 13 host species surveyed. Sequences of rDNA extracted from these isolates indicate that a ubiquitous Ichthyophonus type occurs in the NE Pacific Ocean and Bering Sea and accounts for nearly all the infections encountered. Among NE Pacific isolates, only parasites from yellowtail rockfish and Puget Sound rockfish varied at the DNA locus examined. These data suggest that a single source population of these parasites is available to fishes in diverse niches across a wide geographic range. A direct life cycle within a common forage species could account for the relatively low parasite diversity we encountered. In the laboratory we tested the hypothesis that waterborne transmission occurs among Pacific herring, a common NE Pacific forage species. No horizontal transmission occurred during a four-month cohabitation experiment involving infected herring and conspecific sentinels. The complete life cycle of Ichthyophonus spp. is not known, but these results suggest that system-wide processes maintain a relatively homogenous parasite population.
Johnson, M T J; Agrawal, A A; Maron, J L; Salminen, J-P
2009-06-01
This study explored genetic variation and co-variation in multiple functional plant traits. Our goal was to characterize selection, heritabilities and genetic correlations among different types of traits to gain insight into the evolutionary ecology of plant populations and their interactions with insect herbivores. In a field experiment, we detected significant heritable variation for each of 24 traits of Oenothera biennis and extensive genetic covariance among traits. Traits with diverse functions formed several distinct groups that exhibited positive genetic covariation with each other. Genetic variation in life-history traits and secondary chemistry together explained a large proportion of variation in herbivory (r(2) = 0.73). At the same time, selection acted on lifetime biomass, life-history traits and two secondary compounds of O. biennis, explaining over 95% of the variation in relative fitness among genotypes. The combination of genetic covariances and directional selection acting on multiple traits suggests that adaptive evolution of particular traits is constrained, and that correlated evolution of groups of traits will occur, which is expected to drive the evolution of increased herbivore susceptibility. As a whole, our study indicates that an examination of genetic variation and covariation among many different types of traits can provide greater insight into the evolutionary ecology of plant populations and plant-herbivore interactions.
Daskalakis, Nikolaos P.; Bagot, Rosemary C.; Parker, Karen J.; Vinkers, Christiaan H.; de Kloet, E. R.
2013-01-01
Stressful experiences during early-life can modulate the genetic programming of specific brain circuits underlying emotional and cognitive aspects of behavioral adaptation to stressful experiences later in life. Although this programming effect exerted by experience-related factors is an important determinant of mental health, its outcome depends on cognitive inputs and hence the valence an individual assigns to a given environmental context. From this perspective we will highlight, with studies in rodents, non-human primates and humans, the three-hit concept of vulnerability and resilience to stress-related mental disorders, which is based on gene-environment interactions during critical phases of perinatal and juvenile brain development. The three-hit (i.e., hit-1: genetic predisposition, hit-2: early-life environment, and hit-3: later-life environment) concept accommodates the cumulative stress hypothesis stating that in a given context vulnerability is enhanced when failure to cope with adversity accumulates. Alternatively, the concept also points to the individual’s predictive adaptive capacity, which underlies the stress inoculation and match/mismatch hypotheses. The latter hypotheses propose that the experience of relatively mild early-life adversity prepares for the future and promotes resilience to similar challenges in later-life; when a mismatch occurs between early and later-life experience, coping is compromised and vulnerability is enhanced. The three-hit concept is fundamental for understanding how individuals can either be prepared for coping with life to come and remain resilient or are unable to do so and succumb to a stress-related mental disorder, under seemingly identical circumstances. PMID:23838101
Daskalakis, Nikolaos P; Bagot, Rosemary C; Parker, Karen J; Vinkers, Christiaan H; de Kloet, E R
2013-09-01
Stressful experiences during early-life can modulate the genetic programming of specific brain circuits underlying emotional and cognitive aspects of behavioral adaptation to stressful experiences later in life. Although this programming effect exerted by experience-related factors is an important determinant of mental health, its outcome depends on cognitive inputs and hence the valence an individual assigns to a given environmental context. From this perspective we will highlight, with studies in rodents, non-human primates and humans, the three-hit concept of vulnerability and resilience to stress-related mental disorders, which is based on gene-environment interactions during critical phases of perinatal and juvenile brain development. The three-hit (i.e., hit-1: genetic predisposition, hit-2: early-life environment, and hit-3: later-life environment) concept accommodates the cumulative stress hypothesis stating that in a given context vulnerability is enhanced when failure to cope with adversity accumulates. Alternatively, the concept also points to the individual's predictive adaptive capacity, which underlies the stress inoculation and match/mismatch hypotheses. The latter hypotheses propose that the experience of relatively mild early-life adversity prepares for the future and promotes resilience to similar challenges in later-life; when a mismatch occurs between early and later-life experience, coping is compromised and vulnerability is enhanced. The three-hit concept is fundamental for understanding how individuals can either be prepared for coping with life to come and remain resilient or are unable to do so and succumb to a stress-related mental disorder, under seemingly identical circumstances. Copyright © 2013 Elsevier Ltd. All rights reserved.
Gas Path On-line Fault Diagnostics Using a Nonlinear Integrated Model for Gas Turbine Engines
NASA Astrophysics Data System (ADS)
Lu, Feng; Huang, Jin-quan; Ji, Chun-sheng; Zhang, Dong-dong; Jiao, Hua-bin
2014-08-01
Gas turbine engine gas path fault diagnosis is closely related technology that assists operators in managing the engine units. However, the performance gradual degradation is inevitable due to the usage, and it result in the model mismatch and then misdiagnosis by the popular model-based approach. In this paper, an on-line integrated architecture based on nonlinear model is developed for gas turbine engine anomaly detection and fault diagnosis over the course of the engine's life. These two engine models have different performance parameter update rate. One is the nonlinear real-time adaptive performance model with the spherical square-root unscented Kalman filter (SSR-UKF) producing performance estimates, and the other is a nonlinear baseline model for the measurement estimates. The fault detection and diagnosis logic is designed to discriminate sensor fault and component fault. This integration architecture is not only aware of long-term engine health degradation but also effective to detect gas path performance anomaly shifts while the engine continues to degrade. Compared to the existing architecture, the proposed approach has its benefit investigated in the experiment and analysis.
Development and applicability of a ready-to-use PCR system for GMO screening.
Rosa, Sabrina F; Gatto, Francesco; Angers-Loustau, Alexandre; Petrillo, Mauro; Kreysa, Joachim; Querci, Maddalena
2016-06-15
With the growing number of GMOs introduced to the market, testing laboratories have seen their workload increase significantly. Ready-to-use multi-target PCR-based detection systems, such as pre-spotted plates (PSP), reduce analysis time while increasing capacity. This paper describes the development and applicability to GMO testing of a screening strategy involving a PSP and its associated web-based Decision Support System. The screening PSP was developed to detect all GMOs authorized in the EU in one single PCR experiment, through the combination of 16 validated assays. The screening strategy was successfully challenged in a wide inter-laboratory study on real-life food/feed samples. The positive outcome of this study could result in the adoption of a PSP screening strategy across the EU; a step that would increase harmonization and quality of GMO testing in the EU. Furthermore, this system could represent a model for other official control areas where high-throughput DNA-based detection systems are needed. Copyright © 2016 The Authors. Published by Elsevier Ltd.. All rights reserved.
Detection of dominant flow and abnormal events in surveillance video
NASA Astrophysics Data System (ADS)
Kwak, Sooyeong; Byun, Hyeran
2011-02-01
We propose an algorithm for abnormal event detection in surveillance video. The proposed algorithm is based on a semi-unsupervised learning method, a kind of feature-based approach so that it does not detect the moving object individually. The proposed algorithm identifies dominant flow without individual object tracking using a latent Dirichlet allocation model in crowded environments. It can also automatically detect and localize an abnormally moving object in real-life video. The performance tests are taken with several real-life databases, and their results show that the proposed algorithm can efficiently detect abnormally moving objects in real time. The proposed algorithm can be applied to any situation in which abnormal directions or abnormal speeds are detected regardless of direction.
Moreno-Paz, Mercedes; Gómez-Cifuentes, Ana; Ruiz-Bermejo, Marta; Hofstetter, Oliver; Maquieira, Ángel; Manchado, Juan M; Morais, Sergi; Sephton, Mark A; Niessner, Reinhard; Knopp, Dietmar; Parro, Victor
2018-04-11
Potential martian molecular targets include those supplied by meteoritic carbonaceous chondrites such as amino acids and polycyclic aromatic hydrocarbons and true biomarkers stemming from any hypothetical martian biota (organic architectures that can be directly related to once living organisms). Heat extraction and pyrolysis-based methods currently used in planetary exploration are highly aggressive and very often modify the target molecules making their identification a cumbersome task. We have developed and validated a mild, nondestructive, multiplex inhibitory microarray immunoassay and demonstrated its implementation in the SOLID (Signs of Life Detector) instrument for simultaneous detection of several nonvolatile life- and nonlife-derived organic molecules relevant in planetary exploration and environmental monitoring. By utilizing a set of highly specific antibodies that recognize D- or L- aromatic amino acids (Phe, Tyr, Trp), benzo[a]pyrene (B[a]P), pentachlorophenol, and sulfone-containing aromatic compounds, respectively, the assay was validated in the SOLID instrument for the analysis of carbon-rich samples used as analogues of the organic material in carbonaceous chondrites or even Mars samples. Most of the antibodies enabled sensitivities at the 1-10 ppb level and some even at the ppt level. The multiplex immunoassay allowed the detection of B[a]P as well as aromatic sulfones in a water/methanol extract of an Early Cretaceous lignite sample (c.a., 140 Ma) representing type IV kerogen. No L- or D-aromatic amino acids were detected, reflecting the advanced diagenetic stage and the fossil nature of the sample. The results demonstrate the ability of the liquid extraction by ultrasonication and the versatility of the multiplex inhibitory immunoassays in the SOLID instrument to discriminate between organic matter derived from life and nonlife processes, an essential step toward life detection outside Earth. Key Words: Planetary exploration-Molecular biomarkers-D- and L- aromatic amino acids-Life detection-Multiplex inhibitory/competitive immunoassay-Kerogen type IV. Astrobiology 18, xxx-xxx.
Highly Sensitive Tunable Diode Laser Spectrometers for In Situ Planetary Exploration
NASA Technical Reports Server (NTRS)
Vasudev, Ram; Mansour, Kamjou; Webster, Christopher R.
2013-01-01
This paper describes highly sensitive tunable diode laser spectrometers suitable for in situ planetary exploration. The technology developed at JPL is based on wavelength modulated cavity enhanced absorption spectroscopy. It is capable of sensitively detecting chemical signatures of life through the abundance of biogenic molecules and their isotopic composition, and chemicals such as water necessary for habitats of life. The technology would be suitable for searching for biomarkers, extinct life, potential habitats of extant life, and signatures of ancient climates on Mars; and for detecting biomarkers, prebiotic chemicals and habitats of life in the outer Solar System. It would be useful for prospecting for water on the Moon and asteroids, and characterizing its isotopic composition. Deployment on the Moon could provide ground truth to the recent remote measurements and help to uncover precious records of the early bombardment history of the inner Solar System buried at the shadowed poles, and elucidate the mechanism for the generation of near-surface water in the illuminated regions. The technology would also be useful for detecting other volatile molecules in planetary atmospheres and subsurface reservoirs, isotopic characterization of planetary materials, and searching for signatures of extinct life preserved in solid matrices.
Automatic guidance of attention during real-world visual search.
Seidl-Rathkopf, Katharina N; Turk-Browne, Nicholas B; Kastner, Sabine
2015-08-01
Looking for objects in cluttered natural environments is a frequent task in everyday life. This process can be difficult, because the features, locations, and times of appearance of relevant objects often are not known in advance. Thus, a mechanism by which attention is automatically biased toward information that is potentially relevant may be helpful. We tested for such a mechanism across five experiments by engaging participants in real-world visual search and then assessing attentional capture for information that was related to the search set but was otherwise irrelevant. Isolated objects captured attention while preparing to search for objects from the same category embedded in a scene, as revealed by lower detection performance (Experiment 1A). This capture effect was driven by a central processing bottleneck rather than the withdrawal of spatial attention (Experiment 1B), occurred automatically even in a secondary task (Experiment 2A), and reflected enhancement of matching information rather than suppression of nonmatching information (Experiment 2B). Finally, attentional capture extended to objects that were semantically associated with the target category (Experiment 3). We conclude that attention is efficiently drawn towards a wide range of information that may be relevant for an upcoming real-world visual search. This mechanism may be adaptive, allowing us to find information useful for our behavioral goals in the face of uncertainty.
ERIC Educational Resources Information Center
Ceaser, Donovon
2015-01-01
Significant life experiences (SLE) research has been criticized for a disproportionate focus on privileged groups and positive experiences. In this paper, I use textual analysis to examine the SLEs within the Environmental Justice (EJ) literature. Theoretically, I blend feminist theory, the sociology of disaster, and research on EJ motives for…
Brorson, Hanna; Plymoth, Henrietta; Örmon, Karin; Bolmsjö, Ingrid
2014-03-01
Patients with dementia receive suboptimal palliative care, and this patient group is at risk to have pain at the end of life. Because communicative impairments are common in this patient group, nurses play an important caregiver role in identifying, assessing, and relieving patients' pain. This study aimed to describe nurses' experiences regarding end-of-life pain relief in patients with dementia. This descriptive exploratory qualitative study was based on seven semistructured interviews. Burnard's content analysis inspired the data analysis. Two main categories were identified: (1) nurses' experience of difficulties concerning pain relief and (2) nurses' experience of resources concerning pain relief. Nurses experienced difficulties, such as feeling of powerlessness because of difficulties in obtaining adequate prescriptions for analgesics, ethical dilemmas, feeling of inadequacy because analgesia did not have the desired effect, and a feeling of not being able to connect with the patient. Factors, including knowledge about the patient, professional experience, utilization of pain assessment tools, interpersonal relationships, and interprofessional cooperation, served as resources and enabled end-of-life pain relief. The results of this study highlight the complexity of pain relief in patients with dementia at the end of life from a nursing perspective. The inability of patients with dementia to verbally communicate their pain makes them a vulnerable patient group, dependent on their caregivers. Knowing the life story of the patient, professional experience, teamwork based on good communication, and use of a pain assessment tool were reported by the nurses to improve pain relief at the end of life for patients with dementia. Copyright © 2014 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.
Abiogenic synthesis of nucleotides on the surface of small space bodies with high energy particles
NASA Astrophysics Data System (ADS)
Simakov, M. B.; Kuzicheva, E. A.; Antropov, A. E.; Dodonova, N. Ya
Abiotic formation of such complex biochemical compounds as nucleotides and oligopeptides on the surface of interstellar and interplanetary dust particles (IDP) by cosmic radiation was examined. In order to study the formation of organic compounds on IDPs, solid films prepared from nucleososide and inorganic phosphate were irradiated with high energy protons. Irradiated products were analyzed with HPLC. The natural nucleotides were detected. The main products were 5' AMP (3.2%) and 2'3' cAMP (2.7%). The results were compared with others experiments on the action of ultraviolet radiation with different wavelengths, γ-radiation and heat on solid mixtures of biologically significant compounds. The experiment on abiogenic synthesis of nucleotides on board of space satellite "BION-11" was compared also. The present results suggest that a considerable amount of complex biochemical compounds formed in extraterrestrial environments could have been supplied to the primitive earth before the origin of life.
Gender and Age Differences in Trauma and PTSD Among Dutch Treatment-Seeking Police Officers.
van der Meer, Christianne A I; Bakker, Anne; Smit, Annika S; van Buschbach, Susanne; den Dekker, Melissa; Westerveld, Gré J; Hutter, Renée C; Gersons, Berthold P R; Olff, Miranda
2017-02-01
Little is known about how age and gender are associated with posttraumatic stress disorder (PTSD) symptoms and traumatic experiences in treatment-seeking police offers. In this study, we examined 967 diagnostic files of police officers seeking treatment for PTSD. Six hundred twelve (63%) of the referred police officers were diagnosed with PTSD (n = 560) or partial PTSD (n = 52). Police officers reported on average 19.5 different types of traumatic events (range 1-43). Those who experienced a greater variety of traumatic events suffered from more PTSD symptoms. Also, women reported more often direct life-threatening or private events as their index trauma than men and suffered from more PTSD symptoms than their male colleagues. Results indicate that police officers experience a considerable number of different traumatic events, which is significantly associated with PTSD symptoms. The results highlight the importance of early detection of PTSD symptoms in the police force.
Badger, Sarah; Macleod, Rod; Honey, Anne
2016-06-01
A key aim of palliative care is to improve the quality-of-life of people with a life-threatening illness. Occupational therapists are well positioned to contribute to this aim due to their broad range of interventions, client-centeredness and focus on occupation. However, there is a limited understanding of how occupational therapy contributes to the end-of-life experience, which is crucial to providing optimal care. The aim of this study is to investigate the lived experience of occupational therapy in palliative care for people with a life-threatening illness. A hermeneutic interpretive phenomenological approach was adopted. Semi-structured interviews were conducted with eight participants recruited from inpatient and outpatient sectors of a specialist palliative care hospital in Sydney, Australia. The two themes developed from participant responses were: (1) occupational therapy provides comfort and safety and (2) trusting the occupational therapist to know what is needed. This study gives insight into the ways in which people with a life-threatening illness experience occupational therapy in palliative care. In addition, it provides a starting point to guide practice that is attentive to the needs of people with a life-threatening illness at end-of-life, thus enhancing client-centered care.
Lesuis, Sylvie L; Maurin, Herve; Borghgraef, Peter; Lucassen, Paul J; Van Leuven, Fred; Krugers, Harm J
2016-06-28
Stress has been implicated as a risk factor for the severity and progression of sporadic Alzheimer's disease (AD). Early life experiences determine stress responsivity in later life, and modulate age-dependent cognitive decline. Therefore, we examined whether early life experiences influence AD outcome in a bigenic mouse model which progressively develops combined tau and amyloid pathology (biAT mice).Mice were subjected to either early life stress (ELS) or to 'positive' early handling (EH) postnatally (from day 2 to 9). In biAT mice, ELS significantly compromised long term survival, in contrast to EH which increased life expectancy. In 4 month old mice, ELS-reared biAT mice displayed increased hippocampal Aβ levels, while these levels were reduced in EH-reared biAT mice. No effects of ELS or EH were observed on the brain levels of APP, protein tau, or PSD-95. Dendritic morphology was moderately affected after ELS and EH in the amygdala and medial prefrontal cortex, while object recognition memory and open field performance were not affected. We conclude that despite the strong transgenic background, early life experiences significantly modulate the life expectancy of biAT mice. Parallel changes in hippocampal Aβ levels were evident, without affecting cognition of young adult biAT mice.
Ørtenblad, Lisbeth; Væggemose, Ulla; Gissel, Lene; Nissen, Nina Konstantin
2018-02-06
Challenges in recruiting volunteers encountered by psychiatric services are barely elucidated despite a general societal increase in volunteering. The aim of the study was to explore the significance of professional and private life experiences in willingness to volunteer to care for people with severe mental illness. Focus group interviews with volunteers in the Community Family Programme was conducted, followed by thematic analysis. All interviewees had professional and/or private experience of SMI, which had a major influence on their initial willingness to volunteer. Volunteering was an opportunity to pass on their experiences and to care for SMI people in ways that were not possible in their professions. The interviewees did not distinguish between the influences of professional and/or private life experiences on their willingness to volunteer. The study demonstrates the importance of professional and/or private life experiences in initial considerations about volunteering for mental health care. The consequences for recruitment practices are discussed.
Damage Assessment of Creep Tested and Thermally Aged Udimet 520 Using Acousto-Ultrasonics
NASA Technical Reports Server (NTRS)
Gyekenyesi, Andrew L.; Kautz, Harold E.; Cao, Wei
2001-01-01
Due to elevated temperatures and excessive stresses, turbine components may experience creep behavior. As a result, it is desirable to monitor and assess the current condition of such components. This study employed the Acousto-Ultrasonics (AU) method in an effort to monitor the state of the material at various percentages of used up creep life in the nickel base alloy, Udimet 520. A stepped specimen (i.e., varying cross sectional area) was employed which allowed for a postmortem nondestructive evaluation (NDE) analysis of the various levels of used up life. The overall objectives here were two fold: First, a user friendly, graphical interface AU system was developed, and second the new AU system was applied as an NDE tool to assess distributed damage resulting from creep. The experimental results demonstrated that the AU method shows promise as an NDE tool capable of detecting material changes as a function of used up creep life. Furthermore, the changes in the AU parameters were mainly attributed to the case of combined load and elevated temperature (i.e., creep) and not simply because of a timed exposure at elevated temperature (i.e., heat treatment or thermal aging).
Results of inphase axial-torsional fatigue experiments on 304 stainless steel
NASA Technical Reports Server (NTRS)
Bonacuse, Peter J.; Kalluri, Sreeramesh
1989-01-01
A series of axial-torsional, inphase, strain-controlled, low-cycle fatigue tests were performed at room temperature on tubular specimens of 304 stainless steel. The program was conducted in cooperation with the task group on multiaxial fatigue research of ASTM committee E-09. The objective was to quantify the variability in multiaxial test results among several laboratories. Only included is data which was generated at the NASA Lewis Research Center's High Temperature Fatigue and Structures Laboratory. The experimental equipment and procedures used are described. The tubular specimens were polished on the outer surface to aid in the use of a cellulose film surface replication technique for crack detection. However, cracking initiated predominantly on the internal surface for all specimens. Honing of the bore of the tubular specimens lessened but did not entirely eliminate this problem. The observed fatigue lives are compared with lives calculated from three multiaxial life models. Constants for the life prediction models were obtained from uniaxial and torsional tests performed on the same heat of material. The observed fatigue lives agreed with calculated lives to within a factor of two for all but one of the life prediction models.
Park, YoungAh; Fritz, Charlotte
2015-03-01
Research has indicated the importance of recovery from work stress for employee well-being and work engagement. However, very little is known about the specific factors that may support or hinder recovery in the context of dual-earner couples. This study proposes spousal recovery support as a potential resource that dual-earner couples can draw on to enhance their recovery experiences and well-being. It was hypothesized that spousal recovery support would be related to the recipient spouse's life satisfaction via his or her own recovery experiences (i.e., psychological detachment, relaxation, and mastery experiences). The study further investigated the crossover of life satisfaction between working spouses as a potential outcome of recovery processes. Data from 318 full-time employed married couples in South Korea were analyzed using structural equation modeling. Results showed that spousal recovery support was positively related to all 3 recovery experiences of the recipient spouse. Moreover, this recovery support was related to the recipient spouse's life satisfaction via relaxation and mastery experiences. Unexpectedly, psychological detachment was negatively related to life satisfaction, possibly indicating a suppression effect. Life satisfaction crossed over between working spouses. No gender differences were found in the hypothesized paths. Based on these findings, theoretical and practical implications are discussed, and future research directions are presented. PsycINFO Database Record (c) 2015 APA, all rights reserved.
Chuang, Yeu-Hui; Kuo, Li-Min
2018-05-24
The prevalence of depressive symptoms among older residents in long-term care facilities (LTCFs) is high. Nurses are the main healthcare providers in LTCFs and also the persons responsible for detecting changes in residents' mental function and providing subsequent care. Therefore, it is necessary to understand nurses' knowledge, attitudes, and confidence regarding care for older residents with depressive symptoms or depression. This study aimed to understand nurses' level of knowledge of late-life depression, attitudes towards depression, and confidence levels in caring for older adults with depressive symptoms or depression in LTCFs. A cross-sectional descriptive and correlational research design was used. A nationwide self-report survey was conducted in 2016. Ultimately, 556 valid questionnaires were returned. The study found that LTCF nurses' knowledge about late-life depression was poor, and they also lacked confidence in managing and caring for older persons with depressive symptoms or depression, but nurses' attitudes towards depression were neutral or slightly positive. Moreover, nurses who had greater confidence in providing care for older persons with depression were those with more positive attitudes towards depression, a greater interest level in taking care of older adults with depression, less late-life depression knowledge, longer nursing experience in LTCFs, and a greater interest level in late-life depression issues, and who had read late-life depression pamphlets or taken courses or classes in late-life depression. The findings suggest an urgent need to develop strategies to improve nurses' late-life depression knowledge and increase their confidence in providing care to older residents with depressive symptoms or depression. © 2018 Australian College of Mental Health Nurses Inc.
Longitudinal study of DNA methylation during the first 5 years of life.
Urdinguio, Rocio G; Torró, María Isabel; Bayón, Gustavo F; Álvarez-Pitti, Julio; Fernández, Agustín F; Redon, Pau; Fraga, Mario F; Lurbe, Empar
2016-06-03
Early life epigenetic programming influences adult health outcomes. Moreover, DNA methylation levels have been found to change more rapidly during the first years of life. Our aim was the identification and characterization of the CpG sites that are modified with time during the first years of life. We hypothesize that these DNA methylation changes would lead to the detection of genes that might be epigenetically modulated by environmental factors during early childhood and which, if disturbed, might contribute to susceptibility to diseases later in life. The study of the DNA methylation pattern of 485577 CpG sites was performed on 30 blood samples from 15 subjects, collected both at birth and at 5 years old, using Illumina(®) Infinium 450 k array. To identify differentially methylated CpG (dmCpG) sites, the methylation status of each probe was examined using linear models and the Empirical Bayes Moderated t test implemented in the limma package of R/Bioconductor. Surogate variable analysis was used to account for batch effects. DNA methylation levels significantly changed from birth to 5 years of age in 6641 CpG sites. Of these, 36.79 % were hypermethylated and were associated with genes related mainly to developmental ontology terms, while 63.21 % were hypomethylated probes and associated with genes related to immune function. Our results suggest that DNA methylation alterations with age during the first years of life might play a significant role in development and the regulation of leukocyte-specific functions. This supports the idea that blood leukocytes experience genome remodeling related to their interaction with environmental factors, underlining the importance of environmental exposures during the first years of life and suggesting that new strategies should be take into consideration for disease prevention.
Life stories of young women who experience rejection from their mothers.
Mosman, Selina C; Poggenpoel, Marie; Myburgh, Chris
2015-08-12
When a daughter perceives rejection from her mother, she is bound to be sensitive to rejection for most if not all of her life. Such an experience influences almost all future relationships. The purpose of this research was to explore and describe the life stories of young women who perceived rejection from their mothers and to formulate guidelines to assist them. A phenomenological interpretive method that is explorative, descriptive, and contextual was used to explore everyday life experiences. Network sampling was used. In-depth phenomenological interviews were conducted with the young women so that they could define the most important dimensions of their life stories and elaborate on what is relevant to them. They were asked: 'Tell me your life story.' One of the authors also had a life story of perceived maternal rejection; hence an auto-ethnography was critical and was included in the study. Thematic data analysis was applied. Themes that emerged from the data were that the young women: (1) perceive ongoing challenges in forming and sustaining relationships in their lives; (2) experience their lives as conflicted because their relationship with the central core of their existence, their mother, is perceived as tumultuous; and (3) experience fundamental links to be missing in their 'mother-daughter relationship'. Only a few women were interviewed regarding perceived rejection from their mothers. Further research in this regard is imperative.
Living with Dying in the Pediatric Intensive Care Unit: A Nursing Perspective.
Stayer, Debbie; Lockhart, Joan Such
2016-07-01
Despite reported challenges encountered by nurses who provide palliative care to children, few researchers have examined this phenomenon from the perspective of nurses who care for children with life-threatening illnesses in pediatric intensive care units. To describe and interpret the essence of the experiences of nurses in pediatric intensive care units who provide palliative care to children with life-threatening illnesses and the children's families. A hermeneutic phenomenological study was conducted with 12 pediatric intensive care unit nurses in the northeastern United States. Face-to-face interviews and field notes were used to illuminate the experiences. Five major themes were detected: journey to death; a lifelong burden; and challenges delivering care, maintaining self, and crossing boundaries. These themes were illuminated by 12 subthemes: the emotional impact of the dying child, the emotional impact of the child's death, concurrent grieving, creating a peaceful ending, parental burden of care, maintaining hope for the family, pain, unclear communication by physicians, need to hear the voice of the child, remaining respectful of parental wishes, collegial camaraderie and support, and personal support. Providing palliative care to children with life-threatening illnesses was complex for the nurses. Findings revealed sometimes challenging intricacies involved in caring for dying children and the children's families. However, the nurses voiced professional satisfaction in providing palliative care and in support from colleagues. Although the nurses reported collegial camaraderie, future research is needed to identify additional supportive resources that may help staff process and cope with death and dying. ©2016 American Association of Critical-Care Nurses.
Mars in the late Noachian: Evolution of a habitable surface environment
NASA Astrophysics Data System (ADS)
Johnson, Sarah Stewart
2008-10-01
This dissertation addresses whether simple life forms might have existed on Mars during the late Noachian epoch, and whether those life forms, or their traces, can be detected today. It begins by analyzing the ancient Martian climate in light of new evidence that sulfur chemistry played a prominent role in the planet's early evolution. It finds that sulfur-induced greenhouse warming could have periodically heated the planet enough to support liquid water, thereby creating warm, wet, clement conditions. Moreover, it finds that those warming pulses, while short-lived over geologic time, may have persisted for hundreds of years. If sulfur helped create environmental conditions capable of hosting life, however, it also created conditions that were adverse to sustaining it. In particular, dissipation of sulfur volatiles cooled the climate, and sulfur rainout contributed to the acidity of Martian surface waters. The dissertation therefore proceeds to analyze the potential for persistence and detection of life in terrestrial environments with Mars-like characteristics. It first investigates the potential for detecting ancient life by searching for lipid biomarkers in sulfur-rich acid salt lakes, concluding that a variety of biomarkers may be more resistant to decay than previously believed. It then analyzes soil samples from permafrost, discovering the oldest independently authenticated viable organisms ever found, and positing low-level metabolic activity and DNA repair as a survival mechanism in ancient cells. Finally, the dissertation uses deep sequencing to examine prokaryotic diversity in a terrestrial Mars-like river characterized by low pH and high concentrations of iron and sulfur, with results considered in light of the implications for life detection approaches incorporating new, in situ "PCR in a chip" technology. The dissertation concludes by proposing future work, including the ultimate goal of developing a life detection instrument for Mars. (Copies available exclusively from MIT Libraries, Rm. 14-0551, Cambridge, MA 02139-4307. Ph. 617-253-5668; Fax 617-253-1690.)
NASA Astrophysics Data System (ADS)
Sattler, B.; Tilg, M.; Storrie-Lombardi, M.; Remias, D.; Psenner, R.
2012-04-01
Laser-induced fluorescence emission (L.I.F.E.) is an in situ laser scanning technique to detect photoautotrophic pigments such as phycoerythrin of an ice ecosystem such as supraglacial environments without contamination. The sensitivity of many psychrophiles to even moderate changes in temperature, and the logistical difficulties associated with either in situ analysis or sampling makes it difficult to study microbial metabolism in ice ecosystems in a high resolution. Surface communities of cold ecosystems are highly autotrophic and therefor ideal systems for L.I.F.E examinations. 532nm green lasers excite photopigments in cyanobacteria and produce multiple fluorescence signatures between 550nm and 750nm including carotenoids, phycobiliproteins which would enable a non-invasive in-situ measurement. The sensitivity of many psychrophiles to even moderate changes in temperature, and the logistical difficulties associated with either in situ analysis or sampling makes it difficult to study these cryosphere ecosystems. In general, the ice habitat has to be disrupted using techniques that usually include coring, sawing, and melting. Samples are also often chosen blindly, with little indication of probable biomass. The need for an in situ non-invasive, non-destructive technique to detect, localize, and sample cryosphere biomass in the field is therefore of considerable importance. L.I.F.E has already been tested in remote ecosystems like Antarctica (Lake Untersee, Lake Fryxell), supraglacial environments in the Kongsfjord region in the High Arctic and High Alpine glaciers but until now no calibration was set to convert the L.I.F.E. signal into pigment concentration. Here we describe the standardization for detection of Phycobiliproteins (Phycoerythrine) which are found in red algae, cyanobacteria, and cryptomonads. Similar methods are already used for detection of phytoplankton in liquid systems like oceans and lakes by NASÁs Airborne Oceanographic LIDAR since 1979. The possibility to use L.I.F.E. in ice though is a novelty and provides a promising tool to monitor vanishing ice systems like retreating glaciers.
NASA Astrophysics Data System (ADS)
Hand, Kevin P.; Murray, Alison; Garvin, James; and the Europa Lander Science Definition Team, Project Science Team, and Project Engineering Team.
2017-10-01
In June of 2016 NASA convened a 21-person team of scientists to establish the science goals, objectives, investigations, measurement requirements, and model payload of a Europa lander mission concept. The NASA HQ Charter goals, in priority order, are as follows:1) Search for evidence of life on Europa, 2) Assess the habitability of Europa via in situ techniques uniquely available to a lander mission, 3) Characterize surface and subsurface properties at the scale of the lander to support future exploration of Europa.Within Goal 1, four Objectives were developed for seeking signs of life. These include the need to: a) detect and characterize any organic indicators of past or present life, b) identify and characterize morphological, textural, and other indicators of life, c) detect and characterize any inorganic indicators of past or present life, and d) determine the provenance of Lander-sampled material. Goal 2 focuses on Europa’s habitability and ensures that even in the absence of the detection of any potential biosignatures, significant ocean world science is still achieved. Goal 3 ensures that the landing site region is quantitatively characterized in the context needed for Goals 1 and 2, and that key measurements about Europa’s ice shell are made to enable future exploration.Critically, scientific success cannot be, and should never be, contingent on finding signs of life - such criteria would be levying requirements on how the universe works. Rather, scientific success is defined here as achieving a suite of measurements such that if convincing signs of life are present on Europa’s surface they could be detected at levels comparable to those found in benchmark environments on Earth, and, further, that even if no potential biosignatures are detected, the science return of the mission will significantly advance our fundamental understanding of Europa’s chemistry, geology, geophysics, and habitability.
Comans, Tracy A; Nguyen, Kim-Huong; Mulhern, Brendan; Corlis, Megan; Li, Li; Welch, Alyssa; Kurrle, Susan E; Rowen, Donna; Moyle, Wendy; Kularatna, Sanjeewa; Ratcliffe, Julie
2018-01-01
Introduction Generic instruments for assessing health-related quality of life may lack the sensitivity to detect changes in health specific to certain conditions, such as dementia. The Quality of Life in Alzheimer’s Disease (QOL-AD) is a widely used and well-validated condition-specific instrument for assessing health-related quality of life for people living with dementia, but it does not enable the calculation of quality-adjusted life years, the basis of cost utility analysis. This study will generate a preference-based scoring algorithm for a health state classification system -the Alzheimer’s Disease Five Dimensions (AD-5D) derived from the QOL-AD. Methods and analysis Discrete choice experiments with duration (DCETTO) and best–worst scaling health state valuation tasks will be administered to a representative sample of 2000 members of the Australian general population via an online survey and to 250 dementia dyads (250 people with dementia and their carers) via face-to-face interview. A multinomial (conditional) logistic framework will be used to analyse responses and produce the utility algorithm for the AD-5D. Ethics and dissemination The algorithms developed will enable prospective and retrospective economic evaluation of any treatment or intervention targeting people with dementia where the QOL-AD has been administered and will be available online. Results will be disseminated through journals that publish health economics articles and through professional conferences. This study has ethical approval. PMID:29358437
Paradox of Prescribing Late Chemotherapy: Oncologists Explain.
Bluhm, Minnie; Connell, Cathleen M; De Vries, Raymond G; Janz, Nancy K; Bickel, Kathleen E; Silveira, Maria J
2016-12-01
The value of chemotherapy for patients with cancer in the last weeks of life warrants examination. Late chemotherapy may not improve survival or quality of life but typically precludes hospice enrollment and may result in additional symptoms, increased use of other aggressive treatments, and worsening quality of life. Few studies have explored oncologists' rationales for administering chemotherapy near death. This study examines the self-reported factors that influence oncologists' decisions about late chemotherapy. In-depth individual interviews were conducted with 17 oncologists through a semistructured interview guide. Interviews were audio recorded and transcribed verbatim. Transcripts were coded and analyzed using conventional content analysis, a qualitative method that allows the detection and analysis of patterns in the data. Clinical factors take priority in determining late chemotherapy decisions when clear treatment choices exist. When clinical factors are ambiguous, emotion becomes a highly salient influence. Oncologists view late chemotherapy to be patient driven and use it to palliate emotional distress and maintain patient hope even when physical benefit is unexpected. Oncologists experience unique and difficult challenges when caring for dying patients, including emotionally draining communication, overwhelming responsibility for life/death, limitations of oncology to heal, and prognostic uncertainty. These challenges are also eased by offering late chemotherapy. The findings reveal a nuanced understanding of why oncologists find it difficult to refuse chemotherapy treatment for patients near death. Optimal end-of-life treatment decisions require supportive interventions and system change, both of which must take into account the challenges oncologists face.
Garcia, Aileen S.; Alampay, Liane Peña
2013-01-01
This study assessed relations of parental efficacy, experience of stressful life events, and child externalizing behavior to Filipino mothers and fathers’ parental hostility and aggression. Orally-administered surveys were conducted with 117 mothers and 98 fathers for the first year of data collection, and again a year later with 107 mothers and 83 fathers. Path analyses showed that mothers’ report of child externalizing behavior predicted subsequent parental hostility and aggression. For fathers, child externalizing behavior and experience of stressful life events predicted parental hostility and aggression. Additionally, fathers’ parental efficacy was found to moderate the relationship between experience of stressful life events and parental hostility and aggression. Results suggest that child externalizing behavior and experience of stressful life events have direct relations to parental hostility and aggression, while parental efficacy has a moderating effect to it. The differences between the results for fathers and mothers are explained in the context of distinct parenting roles and parenting in the local context. PMID:25284911
Single molecule detection, thermal fluctuation and life
YANAGIDA, Toshio; ISHII, Yoshiharu
2017-01-01
Single molecule detection has contributed to our understanding of the unique mechanisms of life. Unlike artificial man-made machines, biological molecular machines integrate thermal noises rather than avoid them. For example, single molecule detection has demonstrated that myosin motors undergo biased Brownian motion for stepwise movement and that single protein molecules spontaneously change their conformation, for switching to interactions with other proteins, in response to thermal fluctuation. Thus, molecular machines have flexibility and efficiency not seen in artificial machines. PMID:28190869
Damage detection of an in-service condensation pipeline joint
NASA Astrophysics Data System (ADS)
Briand, Julie; Rezaei, Davood; Taheri, Farid
2010-04-01
The early detection of damage in structural or mechanical systems is of vital importance. With early detection, the damage may be repaired before the integrity of the system is jeopardized, resulting in monetary losses, loss of life or limb, and environmental impacts. Among the various types of structural health monitoring techniques, vibration-based methods are of significant interest since the damage location does not need to be known beforehand, making it a more versatile approach. The non-destructive damage detection method used for the experiments herein is a novel vibration-based method which uses an index called the EMD Energy Damage Index, developed with the aim of providing improved qualitative results compared to those methods currently available. As part of an effort to establish the integrity and limitation of this novel damage detection method, field testing was completed on a mechanical pipe joint on a condensation line, located in the physical plant of Dalhousie University. Piezoceramic sensors, placed at various locations around the joint were used to monitor the free vibration of the pipe imposed through the use of an impulse hammer. Multiple damage progression scenarios were completed, each having a healthy state and multiple damage cases. Subsequently, the recorded signals from the healthy and damaged joint were processed through the EMD Energy Damage Index developed in-house in an effort to detect the inflicted damage. The proposed methodology successfully detected the inflicted damages. In this paper, the effects of impact location, sensor location, frequency bandwidth, intrinsic mode functions, and boundary conditions are discussed.
Shin, So Youn; Kwon, Kye Chul; Park, Jong Woo; Kim, Ji Myung; Shin, So Young; Koo, Sun Hoe
2012-01-01
Bacterial meningitis is an infectious disease with high rates of mortality and high frequency of severe sequelae. Early identification of causative bacterial and viral pathogens is important for prompt and proper treatment of meningitis and for prevention of life-threatening clinical outcomes. In the present study, we evaluated the value of the Seeplex Meningitis ACE Detection kit (Seegene Inc., Korea), a newly developed multiplex PCR kit employing dual priming oligonucleotide methods, for diagnosing acute meningitis. Analytical sensitivity of the kit was studied using reference strains for each pathogen targeted by the kit, while it's analytical specificity was studied using the human genome DNA and 58 clinically well-identified reference strains. For clinical validation experiment, we used 27 control cerebrospinal fluid (CSF) samples and 78 clinical CSF samples collected from patients at the time of diagnosis of acute meningitis. The lower detection limits ranged from 10(1) copies/µL to 5×10(1) copies/µL for the 12 viral and bacterial pathogens targeted. No cross-reaction was observed. In the validation study, high detection rate of 56.4% was obtained. None of the control samples tested positive, i.e., false-positive results were absent. The Seeplex Meningitis ACE Detection kit showed high sensitivity, specificity, and detection rate for the identification of pathogens in clinical CSF samples. This kit may be useful for rapid identification of important acute meningitis-causing pathogens.
Shin, So Youn; Kwon, Kye Chul; Park, Jong Woo; Kim, Ji Myung; Shin, So Young
2012-01-01
Background Bacterial meningitis is an infectious disease with high rates of mortality and high frequency of severe sequelae. Early identification of causative bacterial and viral pathogens is important for prompt and proper treatment of meningitis and for prevention of life-threatening clinical outcomes. In the present study, we evaluated the value of the Seeplex Meningitis ACE Detection kit (Seegene Inc., Korea), a newly developed multiplex PCR kit employing dual priming oligonucleotide methods, for diagnosing acute meningitis. Methods Analytical sensitivity of the kit was studied using reference strains for each pathogen targeted by the kit, while it's analytical specificity was studied using the human genome DNA and 58 clinically well-identified reference strains. For clinical validation experiment, we used 27 control cerebrospinal fluid (CSF) samples and 78 clinical CSF samples collected from patients at the time of diagnosis of acute meningitis. Results The lower detection limits ranged from 101 copies/µL to 5×101 copies/µL for the 12 viral and bacterial pathogens targeted. No cross-reaction was observed. In the validation study, high detection rate of 56.4% was obtained. None of the control samples tested positive, i.e., false-positive results were absent. Conclusions The Seeplex Meningitis ACE Detection kit showed high sensitivity, specificity, and detection rate for the identification of pathogens in clinical CSF samples. This kit may be useful for rapid identification of important acute meningitis-causing pathogens. PMID:22259778
Ethnographic Approach to Second Life in Education: A Focus on Technological Difficulties
ERIC Educational Resources Information Center
Sponsiello, Marta; Gallego-Arrufat, María-Jesús
2016-01-01
This paper moves from the data collected during an ethnographic research conducted in Second Life, which focuses on the observation of different technological difficulties in educational experiences. The main research interests focused on the social dynamics of educational experiences in Second Life and the opportunity to develop a proper research…
ERIC Educational Resources Information Center
Fakunmoju, Sunday; Donahue, Gilpatrick R.; McCoy, Shandria; Mengel, Alison S.
2016-01-01
Knowledge about life satisfaction and learning experience among first-year graduate students is sparse, despite its relevance to instructional decisions, academic support, and success of students. Adequate knowledge is crucial, as it may help graduate students manage personal and professional life changes associated with graduate education. Using…
Positive Life Experiences: A Qualitative, Cross-Sectional, Longitudinal Study of Gifted Graduates
ERIC Educational Resources Information Center
Peterson, Jean Sunde; Canady, Kate; Duncan, Nancy
2012-01-01
At the culmination of an 11-year qualitative, cross-sectional study of life events, 48 high-ability high school graduates fitting common stereotypes associated with giftedness completed an open-ended questionnaire, part of which focused on positive life experiences and sources of support. Findings included that intense investment in academics,…
Restrictions into Opportunities: How Boundaries in the Life Course Can Shape Educational Pathways
ERIC Educational Resources Information Center
ahmed Shafi, Adeela; Rose, Jo
2014-01-01
This study explores relationships between experiences in initial education, subsequent life experiences/opportunities and the decision to return to education later in life. Semi-structured interviews with seven female returners to education, focused initially upon the women's perceptions of their aspirations and motivations at various ages, how…
Qualitative Exploration of Acculturation and Life-Span Issues of Elderly Asian Americans
ERIC Educational Resources Information Center
Lee, Jee Hyang; Heo, Nanseol; Lu, Junfei; Portman, Tarrell Awe Agahe
2013-01-01
Awareness of aging issues across diverse populations begins the journey toward counselors becoming culturally competent across client life spans. Understanding the life-span experiences of cultural groups is important for helping professionals. The purpose of this research was to gain insight into the qualitative experiences of Asian American…
The Learning Gains and Student Perceptions of a Second Life Virtual Lab
ERIC Educational Resources Information Center
Cobb, Stephanie; Heaney, Rose; Corcoran, Olivia; Henderson-Begg, Stephanie
2009-01-01
This study examines students' reactions to the virtual biosciences laboratory developed in Second Life[R] (SL) at the University of East London. Final year undergraduates and masters students studying biotechnology took part in a trial of a virtual Polymerase Chain Reaction (PCR) experiment in Second Life and evaluated their experience by…
Fu, Yuming; Li, Leyuan; Xie, Beizhen; Dong, Chen; Wang, Mingjuan; Jia, Boyang; Shao, Lingzhi; Dong, Yingying; Deng, Shengda; Liu, Hui; Liu, Guanghui; Liu, Bojie; Hu, Dawei; Liu, Hong
2016-12-01
To conduct crewed simulation experiments of bioregenerative life support systems on the ground is a critical step for human life support in deep-space exploration. An artificial closed ecosystem named Lunar Palace 1 was built through integrating efficient higher plant cultivation, animal protein production, urine nitrogen recycling, and bioconversion of solid waste. Subsequently, a 105-day, multicrew, closed integrative bioregenerative life support systems experiment in Lunar Palace 1 was carried out from February through May 2014. The results show that environmental conditions as well as the gas balance between O 2 and CO 2 in the system were well maintained during the 105-day experiment. A total of 21 plant species in this system kept a harmonious coexistent relationship, and 20.5% nitrogen recovery from urine, 41% solid waste degradation, and a small amount of insect in situ production were achieved. During the 105-day experiment, oxygen and water were recycled, and 55% of the food was regenerated. Key Words: Bioregenerative life support systems (BLSS)-Space agriculture-Space life support-Waste recycle-Water recycle. Astrobiology 16, 925-936.
Schneider, Stefan; Stone, Arthur A.
2017-01-01
Purpose Self-report items in quality of life (QoL) scales commonly use vague quantifiers like “sometimes” or “often” to measure the frequency of health-related experiences. This study examined whether the meaning of such vaguely quantified response options differs depending on people’s medical status and age, which may undermine the validity of QoL group comparisons. Methods Respondents (n = 600) rated the frequency of positive and negative QoL experiences using vague quantifiers (never, rarely, sometimes, often, always) and provided open-ended numeric frequency counts for the same items. Negative binomial regression analyses examined whether the numeric frequencies associated with each vague quantifier differed between medical status (no vs. one or more medical conditions) and age (18–40 years vs. 60+ years) groups. Results Compared to respondents without a chronic condition, those with a medical condition assigned a higher numeric frequency to the same vague quantifiers for negative QoL experiences; this effect was not evident for positive QoL experiences. Older respondents’ numeric frequencies were more extreme (i.e., lower at the low end and somewhat higher at the high end of the response range) than those of younger respondents. After adjusting for these effects, differences in QoL became somewhat more pronounced between medical status groups, but not between age groups. Conclusions The results suggest that people with different medical backgrounds and age do not interpret vague frequency quantifiers on a QoL scale in the same way. Open-ended numeric frequency reports may be useful to detect and potentially correct for differences in the meaning of vague quantifiers. PMID:27071685
Generativity: Lived Experience as Curricular Content.
ERIC Educational Resources Information Center
Wallin, Jason; Graham, Tanya
2002-01-01
Modern educational practice, inspired by the scientific rationalism of the 17th and 18th centuries, focuses on control, certainty, and order, thus rendering students' experiences superficial. Generativity "finds" the curriculum in students' life experiences, giving them relevance and the opportunity to be explored. Where life is not the…
NASA Technical Reports Server (NTRS)
Anderson, M.; Rummel, J. A. (Editor); Deutsch, S. (Editor)
1979-01-01
United States space life science experiments, encompassing 27 years of experience beginning with sounding rocket flights carrying primates (1948) to the last U.S. spaceflight, the joint US/USSR Apollo Test Project (1975), are presented. The information for each experiment includes Principal Investigators, the program and mission on which it was flown, the specimens used, the objectives, protocol, equipment, results, conclusions, and bibliographic reference citations for publications derived from each experiment.
Predictive and Treatment Validity of Life Satisfaction and the Quality of Life Inventory
ERIC Educational Resources Information Center
Frisch, Michael B.; Clark, Michelle P.; Rouse, Steven V.; Rudd, M. David; Paweleck, Jennifer K.; Greenstone, Andrew; Kopplin, David A.
2005-01-01
The clinical and positive psychology usefulness of quality of life, well-being, and life satisfaction assessments depends on their ability to predict important outcomes and to detect intervention-related change. These issues were explored in the context of a program of instrument validation for the Quality of Life Inventory (QOLI) involving 3,927…
Skylab experiments. Volume 4: Life sciences
NASA Technical Reports Server (NTRS)
1973-01-01
The life sciences experiments conducted during Skylab missions are discussed. The general categories of the experiments are as follows: (1) mineral and hormonal balance, (2) hematology and immunology, (3) cardiovascular status, (4) energy expenditure, (5) neurophysiology, and (7) biology. Each experiment within the general category is further identified with respect to the scientific objectives, equipment used, performance, and data to be obtained.
Results on Neutrinoless Double-Beta Decay from Gerda Phase I
NASA Astrophysics Data System (ADS)
Macolino, Carla
2014-12-01
The GERmanium Detector Array, GERDA, is designed to search for neutrinoless double-beta (0νββ) decay of 76Ge and it is installed in the Laboratori Nazionali del Gran Sasso (LNGS) of INFN, Italy. In this review, the detection principle and detector setup of GERDA are described. Also, the main physics results by GERDA Phase I, are discussed. They include the measurement of the half-life of 2νββ decay, the background decomposition of the energy spectrum and the techniques for the discrimination of the background, based on the pulse shape of the signal. In the last part of this review, the estimation of a limit on the half-life of 0νββ (T0ν 1/2>2.1ḑot 1025 yr at 90% C.L.) and the comparison with previous results are discussed. GERDA data from Phase I strongly disfavor the recent claim of 0νββ discovery, based on data from the Heidelberg-Moscow experiment.
NASA Astrophysics Data System (ADS)
Colangeli, L.; Battaglia, R.; della Corte, V.; Esposito, F.; Ferrini, G.; Mazzotta Epifani, E.; Palomba, E.; Palumbo, P.; Panizza, A.; Rotundi, A.
2004-03-01
The knowledge of Martian airborne dust properties and about mechanisms of dust settling/raising to/from the surface are important to determine climate and surface evolution on Mars. Water is an important tracer of climatic changes on long time-scales and is strictly related to the presence of life forms. The study in situ of dust and water vapour properties and evolution in Martian atmosphere is useful to trace back the planet climate, also in function of life form development. This investigation is also appropriate in preparation to future manned exploration of the planet (in relation to hazardous conditions). In this work we discuss the concept of the MEDUSA (Martian Environmental Dust Analyser) experiment that is designed to provide data on grain size and mass distribution, number density, velocity and scattering properties and on water vapour concentration. The instrument is a multisensor system based on optical and impact detection of grains, coupled with cumulative deposition sensors.
Curtis, David S; Fuller-Rowell, Thomas E; Doan, Stacey N; Zgierska, Aleksandra E; Ryff, Carol D
2016-10-01
The role of early life adversity (ELA) in the development of health disparities has not received adequate attention. The current study examined differential exposure and differential vulnerability to ELA as explanations for socioeconomic and racial disparities in body mass index (BMI). Data were derived from a sample of 150 college students (M age = 18.8, SD = 1.0; 45 % African American; 55 % European American) who reported on parents' education and income as well as on exposure to 21 early adverse experiences. Body measurements were directly assessed to determine BMI. In adjusted models, African American students had higher BMI than European Americans. Similarly, background socioeconomic status was inversely associated with BMI. Significant mediation of group disparities through the pathway of ELA was detected, attenuating disparities by approximately 40 %. Furthermore, ELA was more strongly associated with BMI for African Americans than for European Americans. Efforts to achieve health equity may need to more fully consider early adversity.
Röling, Wilfred F M; Aerts, Joost W; Patty, C H Lucas; ten Kate, Inge Loes; Ehrenfreund, Pascale; Direito, Susana O L
2015-06-01
The detection of biomarkers plays a central role in our effort to establish whether there is, or was, life beyond Earth. In this review, we address the importance of considering mineralogy in relation to the selection of locations and biomarker detection methodologies with characteristics most promising for exploration. We review relevant mineral-biomarker and mineral-microbe interactions. The local mineralogy on a particular planet reflects its past and current environmental conditions and allows a habitability assessment by comparison with life under extreme conditions on Earth. The type of mineral significantly influences the potential abundances and types of biomarkers and microorganisms containing these biomarkers. The strong adsorptive power of some minerals aids in the preservation of biomarkers and may have been important in the origin of life. On the other hand, this strong adsorption as well as oxidizing properties of minerals can interfere with efficient extraction and detection of biomarkers. Differences in mechanisms of adsorption and in properties of minerals and biomarkers suggest that it will be difficult to design a single extraction procedure for a wide range of biomarkers. While on Mars samples can be used for direct detection of biomarkers such as nucleic acids, amino acids, and lipids, on other planetary bodies remote spectrometric detection of biosignatures has to be relied upon. The interpretation of spectral signatures of photosynthesis can also be affected by local mineralogy. We identify current gaps in our knowledge and indicate how they may be filled to improve the chances of detecting biomarkers on Mars and beyond.
Daily Patterns of Life Stressors and Their Relation to Health.
1981-03-01
Daily Life Experience Mood Somatic Symptomatol ogy Z0. AIS3 PACT (Continue on veceree od*e If necessar and ident ify by block num~ber) This is the final...it was used in a 90 prospective study of daily experiences, mood, and somatic symptomatology. DD 1473 EDITION Of I NOV GS IS OBSOLETE ~4 ~ L S/N...Both contracts supported our studies exploring the effects of daily life experiences on mood and somatic symptomatology. Our work was divided into two
Death Attitudes Among Middle-Aged Koreans: Role of End-of-Life Care Planning and Death Experiences
Hong, Michin; Hong, Seunghye; Adamek, Margaret E.; Kim, Mee Hye
2017-01-01
The purpose of this study was to examine factors affecting death attitudes among middle-aged Koreans. In addition, the study explored the interaction effect between knowledge about end-of-life care planning and the experience of death of family or friends on death attitudes. The sample was obtained from a national survey with middle-aged adults in South Korea (n = 2,026). Multivariate regression analysis revealed significant main effects and an interaction effect between knowledge about end-of-life care planning and the experience of death on death attitudes. Greater knowledge of end-of-life care planning was associated with more positive attitudes toward death; however, the effect was stronger for those who had not experienced the death of family or friends. Being older and having greater life satisfaction were also associated with more positive attitudes toward death. This study suggests that end-of-life education can help middle-aged adults embrace the final stage of life and prepare for their own death. PMID:28105867
Death Attitudes Among Middle-Aged Koreans: Role of End-of-Life Care Planning and Death Experiences.
Hong, Michin; Hong, Seunghye; Adamek, Margaret E; Kim, Mee Hye
2018-01-01
The purpose of this study was to examine factors affecting death attitudes among middle-aged Koreans. In addition, the study explored the interaction effect between knowledge about end-of-life care planning and the experience of death of family or friends on death attitudes. The sample was obtained from a national survey with middle-aged adults in South Korea ( n = 2,026). Multivariate regression analysis revealed significant main effects and an interaction effect between knowledge about end-of-life care planning and the experience of death on death attitudes. Greater knowledge of end-of-life care planning was associated with more positive attitudes toward death; however, the effect was stronger for those who had not experienced the death of family or friends. Being older and having greater life satisfaction were also associated with more positive attitudes toward death. This study suggests that end-of-life education can help middle-aged adults embrace the final stage of life and prepare for their own death.
Petri, Suzanne; Berthelsen, Connie B.
2015-01-01
Aim To explore and describe the essential meaning of lived experiences of the phenomenon: Everyday life during curative radiotherapy in patients with non-small-cell lung cancer (NSCLC). Background Radiotherapy treatment in patients with NSCLC is associated with severe side effects such as fatigue, anxiety, and reduced quality of life. However, little is known about the patients’ experience of everyday life during the care trajectory. Design This study takes a reflective lifeworld approach using an empirical application of phenomenological philosophy described by Dahlberg and colleagues. Method A sample of three patients treated with curative radiotherapy for NSCLC was interviewed 3 weeks after the end of radiotherapy treatment about their experiences of everyday life during their treatment. Data were collected in 2014 and interviews and analysis were conducted within the descriptive phenomenological framework. Findings The essential meaning structure of the phenomenon studied was described as “Hope for recovery serving as a compass in a changed everyday life,” which was a guide for the patients through the radiotherapy treatment to support their efforts in coping with side effects. The constituents of the structure were: Radiotherapy as a life priority, A struggle for acceptance of an altered everyday life, Interpersonal relationships for better or worse, and Meeting the health care system. Conclusion The meaning of hope was essential during radiotherapy treatment and our results suggest that interpersonal relationships can be a prerequisite to the experience of hope. “Hope for recovery serving as a compass in a changed everyday life,” furthermore identifies the essentials in the patients’ assertive approach to believing in recovery and thereby enabling hope in a serious situation. PMID:26610116