Ängerud, Karin H; Sederholm Lawesson, Sofia; Isaksson, Rose-Marie; Thylén, Ingela; Swahn, Eva
2017-11-01
In ST-elevation myocardial infarction, time to reperfusion is crucial for the prognosis. Symptom presentation in myocardial infarction influences pre-hospital delay times but studies about differences in symptoms between patients with ST-elevation myocardial infarction and non-ST-elevation myocardial infarction are sparse and inconclusive. The aim was to compare symptoms, first medical contact and pre-hospital delay times in patients with ST-elevation myocardial infarction and non-ST-elevation myocardial infarction. This multicentre, observational study included 694 myocardial infarction patients from five hospitals. The patients filled in a questionnaire about their pre-hospital experiences within 24 h of hospital admittance. Chest pain was the most common symptom in ST-elevation myocardial infarction and non-ST-elevation myocardial infarction (88.7 vs 87.0%, p=0.56). Patients with cold sweat (odds ratio 3.61, 95% confidence interval 2.29-5.70), jaw pain (odds ratio 2.41, 95% confidence interval 1.04-5.58), and nausea (odds ratio 1.70, 95% confidence interval 1.01-2.87) were more likely to present with ST-elevation myocardial infarction, whereas the opposite was true for symptoms that come and go (odds ratio 0.58, 95% confidence interval 0.38-0.90) or anxiety (odds ratio 0.52, 95% confidence interval 0.29-0.92). Use of emergency medical services was higher among patients admitted with ST-elevation myocardial infarction. The pre-hospital delay time from symptom onset to first medical contact was significantly longer in non-ST-elevation myocardial infarction (2:05 h vs 1:10 h, p=0.001). Patients with ST-elevation myocardial infarction differed from those with non-ST-elevation myocardial infarction regarding symptom presentation, ambulance utilisation and pre-hospital delay times. This knowledge is important to be aware of for all healthcare personnel and the general public especially in order to recognise symptoms suggestive of ST-elevation myocardial infarction and when to decide if there is a need for an ambulance.
Tilburt, Jon C; Koller, Kathryn; Tiesinga, James J; Wilson, Robin T; Trinh, Anne C; Hill, Kristin; Hall, Ingrid J; Smith, Judith Lee; Ekwueme, Donatus U; Petersen, Wesley O
2013-11-01
To assess clinical treatment patterns and response times among American Indian/Alaska Native men with a newly elevated PSA. We retrospectively identified men ages 50-80 receiving care in one of three tribally-operated clinics in Northern Minnesota, one medical center in Alaska, and who had an incident PSA elevation (> 4 ng/ml) in a specified time period. A clinical response was considered timely if it was documented as occurring within 90 days of the incident PSA elevation. Among 82 AI/AN men identified from medical records with an incident PSA elevation, 49 (60%) received a timely clinical response, while 18 (22%) had no documented clinical response. One in five AI/AN men in our study had no documented clinical action following an incident PSA elevation. Although a pilot study, these findings suggest the need to improve the documentation, notification, and care following an elevated PSA at clinics serving AI/AN men.
A comparison of bat activity at low and high elevations in the Black Hills of western Washington
Erickson, J.; Adams, Michael J.
2003-01-01
We examined the differences in activity patterns and community structure of bats between low (<150 m) and high ( ! 575 m) elevation sites in two habitats of the Capitol State Forest, Washington. Total bat activity averaged four times higher at low elevation sites than at high elevation sites. Feeding activity was almost 20 times higher at low elevation sites. However, the non-myotis group had similar activity levels at high and low elevation, whereas myotis group activity decreased at higher elevations. Different levels of activity between elevations could be the result of differences in insect availability, climatic conditions, and morphology of the bat species.
Palm, Peter; Gupta, Nidhi; Forsman, Mikael; Skotte, Jørgen; Nordquist, Tobias; Holtermann, Andreas
2018-06-26
Regarding prevention of neck and shoulder pain (NSP), unsupported arm elevation is one factor that should be taken into account when performing work risk assessment. Triaxial accelerometers can be used to measure arm elevation over several days but it is not possible to differentiate between supported and unsupported arm elevation from accelerometers only. Supported arm elevation is more likely to exist during sitting than standing. The aim of the study was to evaluate the use of whole workday measurements of arm elevation with accelerometers to assess potentially harmful work exposure of arm elevation, by comparing arm elevation at work with arm elevation during leisure, in a population with diverse work tasks, and to assess how the exposure parameters were modified when upper arm elevation during sitting time was excluded. The participants, 197 workers belonging to 12 occupational groups with diverse work tasks, wore triaxial accelerometers on the dominant arm, hip, and back for 1-4 days to measure arm elevation and periods of sitting. None of the groups were found to have higher exposure to arm elevation during work compared to leisure. Even though some occupations where known to have work tasks that forced them to work with elevated arms to a large extent. A high proportion of arm elevation derived from sitting time, especially so during leisure. When arm elevation during sitting time was excluded from the analysis, arm elevation was significantly higher at work than during leisure among construction workers, garbage collectors, manufacturing workers, and domestic cleaners. Together this illustrates that it is not suitable to use whole workday measurments of arm elevation with accelerometer as a sole information source when assessing the risk for NSP due to arm elevation. Information on body posture can provide relevant contextual information in exposure assessments when it is known that the potential harmful exposure is performed in standing or walking.
Relating Time-Dependent Acceleration and Height Using an Elevator
NASA Astrophysics Data System (ADS)
Kinser, Jason M.
2015-04-01
A simple experiment in relating a time-dependent linear acceleration function to height is explored through the use of a smartphone and an elevator. Given acceleration as a function of time1, a(t), the velocity function and position functions are determined through integration as in v (t ) =∫ a (t ) d t (1) and x (t ) =∫ v (t ) dt. Mobile devices such as smartphones or tablets have accelerometers that capture slowly evolving acceleration with respect to time and can deliver those measurements as a CSV file. A recent example measured the oscillations of the elevator as it starts its motion.2 In the application presented here the mobile device is used to estimate the height of the elevator ride. By estimating the functional form of the acceleration of an elevator ride, it is possible to estimate the height of the ride through Eqs. (1) and (2).
Oh, Myueng Guen; Han, Mi Ah; Kim, Man Woo; Park, Chan Guk; Kim, Young Dae; Lee, Jun
2016-12-01
The favourable effects of coffee on liver enzymes have been reported worldwide. This study investigated the association between coffee consumption and serum aminotransferase concentration in Korean adults. Data were obtained from the fourth and fifth Korea National Health and Nutrition Examination Surveys. Elevated alanine aminotransferase (ALT) and aspartate aminotransferase (AST) concentration were defined as >30 IU/L for men and >19 IU/L for women. The risk of elevated ALT and AST according to general characteristics and frequency of coffee consumption were tested by chi-square tests and multiple logistic regression analyses. The prevalence of elevated ALT was 27.4%, 27.8%, and 26.9% in subjects who drank <1, 1, and >=2 times/day, respectively. The proportions of individuals with elevated AST were 32.5%, 33.1%, and 26.7% in subjects who drank <1, 1, and >=2 times/day, respectively. The aORs for elevated ALT and AST were significantly lower in subjects who drank >=2 times of coffee/day than in those who drank <1 time/day (ALT: aOR=0.86, 95% CI=0.79-0.94; AST: aOR=0.83, 95% CI=0.76-0.91). In subgroup analysis, consumption of >=2 times/day was associated with lower ORs for elevated ALT in the high-risk group overall and in the viral hepatitis and obesity subgroups, respectively. In sensitivity analysis, reduced frequency of coffee consumption was associated with an increased risk for elevated liver enzymes, although an association between coffee consumption and elevated ALT was not observed in women or current smokers. Higher coffee consumption was associated with lower risk of elevated aminotransferase concentration in Korean adults.
Duodenoscope hang time does not correlate with risk of bacterial contamination.
Heroux, Riley; Sheppard, Michelle; Wright, Sharon B; Sawhney, Mandeep; Hirsch, Elizabeth B; Kalaidjian, Robin; Snyder, Graham M
2017-04-01
Current professional guidelines recommend a maximum hang time for reprocessed duodenoscopes of 5-14 days. We sought to study the association between hang time and risk of duodenoscope contamination. We analyzed cultures of the elevator mechanism and working channel collected in a highly standardized fashion just before duodenoscope use. Hang time was calculated as the time from reprocessing to duodenoscope sampling. The relationship between hang time and duodenoscope contamination was estimated using a calculated correlation coefficient between hang time in days and degree of contamination on the elevator mechanism and working channel. The 18 study duodenoscopes were cultured 531 times, including 465 (87.6%) in the analysis dataset. Hang time ranged from 0.07-39.93 days, including 34 (7.3%) with hang time ≥7.00 days. Twelve cultures (2.6%) demonstrated elevator mechanism and/or working channel contamination. The correlation coefficients for hang time and degree of duodenoscope contamination were very small and not statistically significant (-0.0090 [P = .85] for elevator mechanism and -0.0002 [P = 1.00] for working channel). Odds ratios for hang time (dichotomized at ≥7.00 days) and elevator mechanism and/or working channel contamination were not significant. We did not find a significant association between hang time and risk of duodenoscope contamination. Future guidelines should consider a recommendation of no limit for hang time. Copyright © 2017 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Muñoz, Daniel; Roettig, Mayme L; Monk, Lisa; Al-Khalidi, Hussein; Jollis, James G; Granger, Christopher B
2012-08-01
For patients with ST-segment elevation myocardial infarction transferred for primary percutaneous coronary intervention, guidelines have called for device activation within 90 minutes of initial presentation. Fewer than 20% of transferred patients are treated in such a timely fashion. We examine the association between transfer drive times and door-to-device (D2D) times in a network of North Carolina hospitals. We compare the feasibility of timely percutaneous coronary intervention using ground versus air transfer. We perform a retrospective analysis of the relationship between transfer drive times and D2D times in a 119-hospital ST-segment-elevation myocardial infarction statewide network. Between July 2008 and December 2009, 1537 ST-segment-elevation myocardial infarction patients underwent interhospital transfer for reperfusion via primary percutaneous coronary intervention. For ground transfers, median D2D time was 93 minutes for drive times ≤30 minutes, 117 minutes for drive times of 31 to 45 minutes, and 121 minutes for drive times >45 minutes. For air transfers, median D2D time was 125 minutes for drive times of 31 to 45 minutes and 138 minutes for drive times >45 minutes. Helicopter transport was associated with longer door-in door-out times and, ultimately, was associated with median D2D times that exceeded guideline recommendations, no matter the transfer drive time category. In a well-developed ST-segment-elevation myocardial infarction system, D2D times within 90 to 120 minutes appear most feasible for hospitals within 30-minute transfer drive time. Helicopter transport did not offer D2D time advantages for transferred STEMI patients. This finding appears to be attributable to comparably longer door-in door-out times for air transfers.
NASA Astrophysics Data System (ADS)
Yu, Lu; Zhou, Jin; Mabu, Shingo; Hirasawa, Kotaro; Hu, Jinglu; Markon, Sandor
The Elevator Group Supervisory Control Systems (EGSCS) are the control systems that systematically manage three or more elevators in order to efficiently transport the passengers in buildings. Double-deck elevators, where two elevators are connected with each other, serve passengers at two consecutive floors simultaneously. Double-deck Elevator systems (DDES) become more complex in their behavior than conventional single-deck elevator systems (SDES). Recently, Artificial Intelligence (AI) technology has been used in such complex systems. Genetic Network Programming (GNP), a graph-based evolutionary method, has been applied to EGSCS and its advantages are shown in some papers. GNP can obtain the strategy of a new hall call assignment to the optimal elevator when it performs crossover and mutation operations to judgment nodes and processing nodes. Meanwhile, Destination Floor Guidance System (DFGS) is installed in DDES, so that passengers can also input their destinations at elevator halls. In this paper, we have applied GNP to DDES and compared DFGS with normal systems. The waiting time and traveling time of DFGS are all improved because of getting more information from DFGS. The simulations showed the effectiveness of the double-deck elevators with DFGS in different building traffics.
14 CFR 171.319 - Approach elevation monitor system requirements.
Code of Federal Regulations, 2013 CFR
2013-01-01
... an error in the time division multiplex synchronization of a particular elevation function such that... within the time allowed, radiation shall cease. After shutdown, no attempt must be made to restore...
14 CFR 171.319 - Approach elevation monitor system requirements.
Code of Federal Regulations, 2010 CFR
2010-01-01
... an error in the time division multiplex synchronization of a particular elevation function such that... within the time allowed, radiation shall cease. After shutdown, no attempt must be made to restore...
14 CFR 171.319 - Approach elevation monitor system requirements.
Code of Federal Regulations, 2014 CFR
2014-01-01
... an error in the time division multiplex synchronization of a particular elevation function such that... within the time allowed, radiation shall cease. After shutdown, no attempt must be made to restore...
14 CFR 171.319 - Approach elevation monitor system requirements.
Code of Federal Regulations, 2012 CFR
2012-01-01
... an error in the time division multiplex synchronization of a particular elevation function such that... within the time allowed, radiation shall cease. After shutdown, no attempt must be made to restore...
14 CFR 171.319 - Approach elevation monitor system requirements.
Code of Federal Regulations, 2011 CFR
2011-01-01
... an error in the time division multiplex synchronization of a particular elevation function such that... within the time allowed, radiation shall cease. After shutdown, no attempt must be made to restore...
NASA Astrophysics Data System (ADS)
Henebry, G. M.; Tomaszewska, M. A.; Krehbiel, C. P.; Kelgenbaeva, K.
2016-12-01
To explore the vulnerability of high-elevation communities in the Kyrgyz Republic and in Uzbekistan to changing climatic, sociodemographic, and socioeconomic conditions, we assembled image time series to characterize the condition of pastures near villages at high elevation (>2000 masl) and in remote pastures at higher elevations. Here we describe the application of the convex quadratic (CxQ) model of land surface phenology to highland pasturelands for selected oblasts in the Kyrgyz Republic and in eastern Uzbekistan. We used 16 years (2000-2015) of Landsat normalized difference vegetation index (NDVI) data with MODIS land surface temperature data processed into accumulated growing degree-days. The peak height of the NDVI and the thermal time to peak are two key phenological metrics derived analytically from the fitted parameter coefficients of the CxQ model for each pixel time series. Both exhibited sensitivity to elevation, which we describe in terms of phenometric lapse rates (PLRs). Interannual variation in PLRs was expressed differently for the peak NDVI and the thermal time to peak. Peak NDVI increased with elevation up to a point but also exhibited more spatial variation in dry years than in wetter years. Thermal time to peak exhibited strong, highly significant negative linear relationships to elevation with steeper slopes in drier years. Both types of PLRs were modulated by aspect. These relationships and the associated CxQ models by elevation and aspect can provide expectations against which to detect changes in pasture status as a result of management or weather.
Hirata, Akimasa; Asano, Takayuki; Fujiwara, Osamu
2007-08-21
This study investigated the relationship between the specific absorption rate and temperature elevation in an anatomically-based model named NORMAN for exposure to radio-frequency far fields in the ICNIRP guidelines (1998 Health Phys. 74 494-522). The finite-difference time-domain method is used for analyzing the electromagnetic absorption and temperature elevation in NORMAN. In order to consider the variability of human thermoregulation, parameters for sweating are derived and incorporated into a conventional sweating formula. First, we investigated the effect of blood temperature variation modeling on body-core temperature. The computational results show that the modeling of blood temperature variation was the dominant factor influencing the body-core temperature. This is because the temperature in the inner tissues is elevated via the circulation of blood whose temperature was elevated due to EM absorption. Even at different frequencies, the body-core temperature elevation at an identical whole-body average specific absorption rate (SAR) was almost the same, suggesting the effectiveness of the whole-body average SAR as a measure in the ICNIRP guidelines. Next, we discussed the effect of sweating on the temperature elevation and thermal time constant of blood. The variability of temperature elevation caused by the sweating rate was found to be 30%. The blood temperature elevation at the basic restriction in the ICNIRP guidelines of 0.4 W kg(-1) is 0.25 degrees C even for a low sweating rate. The thermal time constant of blood temperature elevation was 23 min and 52 min for a man with a lower and a higher sweating rate, respectively, which is longer than the average time of the SAR in the ICNIRP guidelines. Thus, the whole-body average SAR required for blood temperature elevation of 1 degrees C was 4.5 W kg(-1) in the model of a human with the lower sweating coefficients for 60 min exposure. From a comparison of this value with the basic restriction in the ICNIRP guidelines of 0.4 W kg(-1), the safety factor was 11.
[Risk factors for elevated serum total bile acid in preterm infants].
Song, Yan-Ting; Wang, Yong-Qin; Zhao, Yue-Hua; Zhu, Hai-Ling; Liu, Qian; Zhang, Xiao; Gao, Yi-Wen; Zhang, Wei-Ye; Sang, Yu-Tong
2018-03-01
To study the risk factors for elevated serum total bile acid (TBA) in preterm infants. A retrospective analysis was performed for the clinical data of 216 preterm infants who were admitted to the neonatal intensive care unit. According to the presence or absence of elevated TBA (TBA >24.8 μmol/L), the preterm infants were divided into elevated TBA group with 53 infants and non-elevated TBA group with 163 infants. A univariate analysis and an unconditional multivariate logistic regression analysis were used to investigate the risk factors for elevated TBA. The univariate analysis showed that there were significant differences between the elevated TBA group and the non-elevated TBA group in gestational age at birth, birth weight, proportion of small-for-gestational-age infants, proportion of infants undergoing ventilator-assisted ventilation, fasting time, parenteral nutrition time, and incidence of neonatal respiratory failure and sepsis (P<0.05). The unconditional multivariate logistic regression analysis showed that low birth weight (OR=3.84, 95%CI: 1.53-9.64) and neonatal sepsis (OR=2.56, 95%CI: 1.01-6.47) were independent risk factors for elevated TBA in preterm infants. Low birth weight and neonatal sepsis may lead to elevated TBA in preterm infants.
Reading, Stephanie R; Porter, Kimberly R; Hsu, Jin-Wen Y; Wallner, Lauren P; Loo, Ronald K; Jacobsen, Steven J
2016-10-01
To examine the racial and ethnic variation in time to prostate biopsy after an elevated screening level of serum prostate-specific antigen (PSA). Male members of the Kaiser Permanente of Southern California health plan, 45 years of age or older, with no history of prostate cancer or a prostate biopsy, and at least 1 elevated screening level of serum PSA between January 1, 1998 and December 31, 2007 were retrospectively identified (n = 59,506). All participants were passively followed via electronic health records until their time of prostate biopsy, death, membership disenrollment, or study conclusion (December 31, 2014), whichever was the initial event. Proportional hazard regression analyses were used to estimate the association between time from an elevated screening level of serum PSA to prostate biopsy, adjusting for age, benign prostatic hyperplasia, prostatitis, type 2 diabetes mellitus, hypertension, and Charlson Comorbidity Index score. Median time until biopsy was 0.6 years (214 days), with approximately 41% of participants receiving a prostate biopsy within the study period. Results from the fully adjusted analysis indicated that the non-Hispanic Asian or Pacific Islanders (hazard ratio: 1.10, 95% confidence interval: [1.04, 1.15]) and the non-Hispanic blacks (hazard ratio: 1.04, 95% confidence interval: [1.00, 1.08]) had a slightly shorter time to prostate biopsy after an elevated screening level of serum PSA compared to the non-Hispanic whites. These data suggest that, within an integrated healthcare organization, minimal differences exist between racial and ethnic subgroups in their time to prostate biopsy after an elevated screening level of serum PSA. Copyright © 2016. Published by Elsevier Inc.
Passive radiation shielding considerations for the proposed space elevator
NASA Astrophysics Data System (ADS)
Jorgensen, A. M.; Patamia, S. E.; Gassend, B.
2007-02-01
The Earth's natural van Allen radiation belts present a serious hazard to space travel in general, and to travel on the space elevator in particular. The average radiation level is sufficiently high that it can cause radiation sickness, and perhaps death, for humans spending more than a brief period of time in the belts without shielding. The exact dose and the level of the related hazard depends on the type or radiation, the intensity of the radiation, the length of exposure, and on any shielding introduced. For the space elevator the radiation concern is particularly critical since it passes through the most intense regions of the radiation belts. The only humans who have ever traveled through the radiation belts have been the Apollo astronauts. They received radiation doses up to approximately 1 rem over a time interval less than an hour. A vehicle climbing the space elevator travels approximately 200 times slower than the moon rockets did, which would result in an extremely high dose up to approximately 200 rem under similar conditions, in a timespan of a few days. Technological systems on the space elevator, which spend prolonged periods of time in the radiation belts, may also be affected by the high radiation levels. In this paper we will give an overview of the radiation belts in terms relevant to space elevator studies. We will then compute the expected radiation doses, and evaluate the required level of shielding. We concentrate on passive shielding using aluminum, but also look briefly at active shielding using magnetic fields. We also look at the effect of moving the space elevator anchor point and increasing the speed of the climber. Each of these mitigation mechanisms will result in a performance decrease, cost increase, and technical complications for the space elevator.
Development and evaluation of a reservoir model for the Chain of Lakes in Illinois
Domanski, Marian M.
2017-01-27
Forecasts of flows entering and leaving the Chain of Lakes reservoir on the Fox River in northeastern Illinois are critical information to water-resource managers who determine the optimal operation of the dam at McHenry, Illinois, to help minimize damages to property and loss of life because of flooding on the Fox River. In 2014, the U.S. Geological Survey; the Illinois Department of Natural Resources, Office of Water Resources; and National Weather Service, North Central River Forecast Center began a cooperative study to develop a system to enable engineers and planners to simulate and communicate flows and to prepare proactively for precipitation events in near real time in the upper Fox River watershed. The purpose of this report is to document the development and evaluation of the Chain of Lakes reservoir model developed in this study.The reservoir model for the Chain of Lakes was developed using the Hydrologic Engineering Center–Reservoir System Simulation program. Because of the complex relation between the dam headwater and reservoir pool elevations, the reservoir model uses a linear regression model that relates dam headwater elevation to reservoir pool elevation. The linear regression model was developed using 17 U.S. Geological Survey streamflow measurements, along with the gage height in the reservoir pool and the gage height at the dam headwater. The Nash-Sutcliffe model efficiency coefficients for all three linear regression model variables ranged from 0.90 to 0.98.The reservoir model performance was evaluated by graphically comparing simulated and observed reservoir pool elevation time series during nine periods of high pool elevation. In addition, the peak elevations during these time periods were graphically compared to the closest-in-time observed pool elevation peak. The mean difference in the simulated and observed peak elevations was -0.03 feet, with a standard deviation of 0.19 feet. The Nash-Sutcliffe coefficient for peak prediction was calculated as 0.94. Evaluation of the model based on accuracy of peak prediction and the ability to simulate an elevation time series showed the performance of the model was satisfactory.
Watkins, Michael L.; Keller, Paul Edwin; Amaya, Ivan A.
2015-06-16
A method of, and apparatus for, determining if a person operating equipment is experiencing an elevated cognitive load, wherein the person's use of a device at a first time is monitored so as to set a baseline signature. Then, at a later time, the person's use of the device is monitored to determine the person's performance at the second time, as represented by a performance signature. This performance signature can then be compared against the baseline signature to predict whether the person is experiencing an elevated cognitive load.
Takatori, Katsuhiko; Matsumoto, Daisuke
2015-10-01
To investigate the relationships between toe elevation ability in the standing position and dynamic balance and fall risk among community-dwelling older adults. Cross-sectional survey. General community. Community-dwelling older adults (N = 287). Toe elevation angles in the standing position. Intra-rater and inter-rater reliability of measurements of the toe elevation angle was high (internal coefficient of correlation [ICC] (1,2) = 0.94 for the former and ICC (2,1) = 0.90 for the latter). Significant correlations were found between the toe elevation angle and age (r = -0.20, P < .01), 5-m walking time (r = -0.31, P < .01), Functional Reach Test (r = 0.36, P < .01), Timed Up and Go Test (r = -0.36, P < .01), and Chair Stand Test (r = 0.26, P < .01). Subjects who experienced a fall in the previous 6 months had a significantly lower toe elevation angle compared with subjects who did not experience a fall (t = 2.19, P < .05). Multiple regression analysis revealed that results of the Functional Reach Test (β = .22, P < .001) and Timed Up and Go Test (β = -0.74, P < .001) were significantly associated with the toe elevation angle. Toe elevation angle was an index of dynamic balance ability and appears to be a simple screening test for fall risk in community-dwelling older adults. Copyright © 2015 American Academy of Physical Medicine and Rehabilitation. Published by Elsevier Inc. All rights reserved.
Hepatitis C prevalence and the significance of liver enzyme elevations in the insurance population.
Stout, R L
1997-01-01
Liver enzyme elevation(s) are a common finding in the insurance applicant population. Hepatitis C infection results in histological and functional changes in the liver with both short and long term changes in serum liver enzyme levels. The prevalence of antibodies to HCV in the general population is estimated to be 4%. This paper reports on the prevalence of antibodies to HCV in the insurance applicant population and their relationship to the liver enzyme(s). Antibodies to HCV are present in 1.8% of a random sampling of insurance applicants. Alanine aminotransferase (ALT) elevations occur in 95.4% of all samples positive for antibodies to HCV. More than half of positive samples (56.7%) have ALT elevations of less than two time the upper range of normal. Antibody prevalence is lowest in samples with single enzyme elevation, 4.2%. In comparison, the prevalence is 16.4% in samples with all three enzymes, ALT, AST, and GGT, elevated. For maximal specificity two immunoassays, configured with different HCV antigens, should be performed sequentially on all positive applicant samples. HCV is the most prevalent, chronic viral infection in the insurance population. HCV prevalence is 40 times HIV prevalence. In an evaluation of enzyme reflex markers ALT was positive for antibodies to HCV 8.6% of the time while identifying 95.4% of HCV antibody positive applicants.
2. Historic American Buildings Survey Robert J. Kelley, Photographer May ...
2. Historic American Buildings Survey Robert J. Kelley, Photographer May 1958 LOOKING NORTH - SHOWS SOUTH ELEVATION, MAIN HOUSE, ROOF OF NORTH ELEVATION AND WEST ELEVATION, WHOSE ROOF WAS RAISED IN RECENT TIMES - Burbank-Hatheway House, Main Street, Suffield, Hartford County, CT
Lessard-Therrien, Malie; Davies, T Jonathan; Bolmgren, Kjell
2014-05-01
Climate change is affecting high-altitude and high-latitude communities in significant ways. In the short growing season of subarctic habitats, it is essential that the timing and duration of phenological phases match favorable environmental conditions. We explored the time of the first appearance of flowers (first flowering day, FFD) and flowering duration across subarctic species composing different communities, from boreal forest to tundra, along an elevational gradient (600-800 m). The study was conducted on Mount Irony (856 m), North-East Canada (54°90'N, 67°16'W) during summer 2012. First, we quantified phylogenetic signal in FFD at different spatial scales. Second, we used phylogenetic comparative methods to explore the relationship between FFD, flowering duration, and elevation. We found that the phylogenetic signal for FFD was stronger at finer spatial scales and at lower elevations, indicating that closely related species tend to flower at similar times when the local environment is less harsh. The comparatively weaker phylogenetic signal at higher elevation may be indicative of convergent evolution for FFD. Flowering duration was correlated significantly with mean FFD, with later-flowering species having a longer flowering duration, but only at the lowest elevation. Our results indicate significant evolutionary conservatism in responses to phenological cues, but high phenotypic plasticity in flowering times. We suggest that phylogenetic relationships should be considered in the search for predictions and drivers of flowering time in comparative analyses, because species cannot be considered as statistically independent. Further, phenological drivers should be measured at spatial scales such that variation in flowering matches variation in environment.
Ishizuka, W; Ono, K; Hara, T; Goto, S
2015-01-01
To avoid winter frost damage, evergreen coniferous species develop cold hardiness with suitable phenology for the local climate regime. Along the elevational gradient, a genetic cline in autumn phenology is often recognised among coniferous populations, but further quantification of evolutionary adaptation related to the local environment and its responsible signals generating the phenological variation are poorly understood. We evaluated the timing of cold hardening among populations of Abies sachalinensis, based on time series freezing tests using trees derived from four seed source populations × three planting sites. Furthermore, we constructed a model to estimate the development of hardening from field temperatures and the intraspecific variations occurring during this process. An elevational cline was detected such that high-elevation populations developed cold hardiness earlier than low-elevation populations, representing significant genetic control. Because development occurred earlier at high-elevation planting sites, the genetic trend across elevation overlapped with the environmental trend. Based on the trade-off between later hardening to lengthen the active growth period and earlier hardening to avoid frost damage, this genetic cline would be adaptive to the local climate. Our modelling approach estimated intraspecific variation in two model components: the threshold temperature, which was the criterion for determining whether the trees accumulated the thermal value, and the chilling requirement for trees to achieve adequate cold hardiness. A higher threshold temperature and a lower chilling requirement could be responsible for the earlier phenology of the high-elevation population. These thermal responses may be one of the important factors driving the elevation-dependent adaptation of A. sachalinensis. © 2014 German Botanical Society and The Royal Botanical Society of the Netherlands.
Relating Time-Dependent Acceleration and Height Using an Elevator
ERIC Educational Resources Information Center
Kinser, Jason M.
2015-01-01
A simple experiment in relating a time-dependent linear acceleration function to height is explored through the use of a smartphone and an elevator. Given acceleration as a function of time, a(t), the velocity function and position functions are determined through integration as in v(t)=? a(t) dt (1) and x(t)=? v(t) dt. Mobile devices such as…
Elevation-relief ratio, hypsometric integral, and geomorphic area-altitude analysis.
NASA Technical Reports Server (NTRS)
Pike, R. J.; Wilson, S. E.
1971-01-01
Mathematical proof establishes identity of hypsometric integral and elevation-relief ratio, two quantitative topographic descriptors developed independently of one another for entirely different purposes. Operationally, values of both measures are in excellent agreement for arbitrarily bounded topographic samples, as well as for low-order fluvial watersheds. By using a point-sampling technique rather than planimetry, elevation-relief ratio (defined as mean elevation minus minimum elevation divided by relief) is calculated manually in about a third of the time required for the hypsometric integral.
Ice elevations and surface change on the Malaspina Glacier, Alaska
Sauber, J.; Molnia, B.; Carabajal, C.; Luthcke, S.; Muskett, R.
2005-01-01
Here we use Ice, Cloud and land Elevation Satellite (ICESat)-derived elevations and surface characteristics to investigate the Malaspina Glacier of southern Alaska. Although there is significant elevation variability between ICESat tracks on this glacier, we were able to discern general patterns in surface elevation change by using a regional digital elevation model (DEM) as a reference surface. Specifically, we report elevation differences between ICESat Laser 1-3 observations (February 2003 - November 2004) and a Shuttle Radar Topography Mission (SRTM)-derived DEM from February 2000. Elevation decreases of up to 20-25 m over a 3-4 year time period were observed across the folded loop moraine on the southern portion of the Malaspina Glacier. Copyright 2005 by the American Geophysical Union.
NASA Technical Reports Server (NTRS)
Zwally, H. Jay; Brenner, Anita C.; Barbieri, Kristine; DiMarzio, John P.; Li, Jun; Robbins, John; Saba, Jack L.; Yi, Donghui
2012-01-01
A primary purpose of satellite altimeter measurements is determination of the mass balances of the Greenland and Antarctic ice sheets and changes with time by measurement of changes in the surface elevations. Since the early 1990's, important measurements for this purpose have been made by radar altimeters on ERS-l and 2, Envisat, and CryoSat and a laser altimeter on ICESat. One principal factor limiting direct comparisons between radar and laser measurements is the variable penetration depth of the radar signal and the corresponding location of the effective depth of the radar-measured elevation beneath the surface, in contrast to the laser-measured surface elevation. Although the radar penetration depth varies significantly both spatially and temporally, empirical corrections have been developed to account for this effect. Another limiting factor in direct comparisons is caused by differences in the size of the laser and radar footprints and their respective horizontal locations on the surface. Nevertheless, derived changes in elevation, dHldt, and time-series of elevation, H(t), have been shown to be comparable. For comparisons at different times, corrections for elevation changes caused by variations in the rate offrrn compaction have also been developed. Comparisons between the H(t) and the average dH/dt at some specific locations, such as the Vostok region of East Antarctic, show good agreement among results from ERS-l and 2, Envisat, and ICESat. However, Greenland maps of dHidt from Envisat and ICESat for the same time periods (2003-2008) show some areas of significant differences as well as areas of good agreement. Possible causes of residual differences are investigated and described.
NASA Astrophysics Data System (ADS)
Sandberg Sørensen, Louise; Simonsen, Sebastian B.; Forsberg, René; Khvorostovsky, Kirill; Meister, Rakia; Engdahl, Marcus E.
2018-08-01
The shape of the large ice sheets responds rapidly to climate change, making the elevation changes of these ice-covered regions an essential climate variable. Consistent, long time series of these elevation changes are of great scientific value. Here, we present a newly-developed data product of 25 years of elevation changes of the Greenland Ice Sheet, derived from satellite radar altimetry. The data product is made publicly available within the Greenland Ice Sheets project as part of the ESA Climate Change Initiative programme. Analyzing repeated elevation measurements from radar altimetry is widely used for monitoring changes of ice-covered regions. The Greenland Ice Sheet has been mapped by conventional radar altimetry since the launch of ERS-1 in 1991, which was followed by ERS-2, Envisat and currently CryoSat-2. The recently launched Sentinel-3A will provide a continuation of the radar altimetry time series. Since 2010, CryoSat-2 has for the first time measured the changes in the coastal regions of the ice sheet with radar altimetry, with its novel SAR Interferometric (SARIn) mode, which provides improved measurement over regions with steep slopes. Here, we apply a mission-specific combination of cross-over, along-track and plane-fit elevation change algorithms to radar data from the ERS-1, ERS-2, Envisat and CryoSat-2 radar missions, resulting in 25 years of nearly continuous elevation change estimates (1992-2016) of the Greenland Ice Sheet. This analysis has been made possible through the recent reprocessing in the REAPER project, of data from the ERS-1 and ERS-2 radar missions, making them consistent with Envisat data. The 25 years of elevation changes are evaluated as 5-year running means, shifted almost continuously by one year. A clear acceleration in thinning is evident in the 5-year maps of elevation following 2003, while only small elevation changes observed in the maps from the 1990s.
Vertilus, Shawyntee M.; Austin, Stephanie L.; Foster, Kimberly S.; Boyette, Keri E.; Bali, Deeksha; Li, Jennifer S.; Kishnani, Priya S.; Wechsler, Stephanie Burns
2013-01-01
Purpose Glycogen Storage Disease (GSD) type III, glycogen debranching enzyme deficiency, causes accumulation of glycogen in liver, skeletal, and cardiac muscle. Some patients develop increased left ventricular (LV) thickness by echocardiography, but the rate of increase and its significance remain unclear. Methods We evaluated 33 patients with GSD type III, 23 with IIIa and 10 with IIIb, ages 1 month – 55.5 yrs, by echocardiography for wall thickness, LV mass, shortening and ejection fractions, at 1 time point (n = 33) and at 2 time points in patients with more than 1 echocardiogram (13 of the 33). Results Of 23 cross-sectional patients with type IIIa, 12 had elevated LV mass, 11 had elevated wall thickness. One type IIIb patient had elevated LV mass but 4 had elevated wall thickness. For those with multiple observations, 9 of 10 with type IIIa developed increased LV mass over time, with 3 already increased at first measurement. Shortening and ejection fractions were generally normal. Conclusion Elevated LV mass and wall thickness is more common in patients with type IIIa but develops rarely in type IIIb, though ventricular systolic function is preserved. This suggests serial echocardiograms with attention to LV thickness and mass are important for care of these patients. PMID:20526204
Research on the ride comfort of elevator monitoring using smartphone
NASA Astrophysics Data System (ADS)
Zhang, Yang; Sun, Xiaowei; Xie, Zhao; Su, Wensheng; Xue, Zhigang; Zhao, Xuefeng
2017-04-01
With the rapid development of high-rise buildings, the requirement of the elevator's speed is growing higher. And the vibration amplitude of elevator will also increasing with the improvement of running speed. The vibration problems of elevator have become the important factors that affect the comfort feeling of elevator. At the same time, the strong vibration will affect the normal work of elevator, and even cause accidents. So it's necessary to study the vibration characteristics of the elevator. In recent years, smartphone has developed rapidly, with a variety of sophisticated sensors; it has the powerful data processing and transmission capacity. In this paper, the author has presented an elevator comfort monitoring method based on smartphone. This method using Monitoring App can monitor the acceleration and inclination information using MEMS sensors embedded in smartphone. Then a confirmatory test for an elevator was designed, experimental results show that elevator comfort monitoring method based on smartphone is stable and reliable.
NASA Astrophysics Data System (ADS)
Hwang, C.; Cheng, Y. S.
2015-12-01
In most cases, mountain glaciers are narrow and situated over steep slopes. A laser-based altimeter such as ICESat has a small illuminated footprint at about 70 m, thus allowing to measure precise elevations over narrow mountain glaciers. However, unlike a typical radar altimeter mission, ICESat does not have repeat ground tracks (except in its early phase) to measure heights of a specific point at different times. Within a time span, usually a reference digital elevation model is used to compute height anomalies at ICESat's measurement sites over a designated area, which are then averaged to produce a representative height change (anomaly) in this area. In contrast, a radar altimeter such as TOPEX/Poseidon (TP; its follow-on missions are Jason-1 and -2), repeats its ground tracks at an even time interval (10 days for TP), but has a larger illuminated footprint than ICESat's (about 1 km or larger), making it difficult to measure precise elevations over narrow mountain glaciers. Here we demonstrate the potential of TP and Jason-2 radar altimeters in detecting elevation changes over mountain glaciers that are sufficiently wide and smooth. We select several glacier-covered sites in Mt. Tanggula (Tibet) and the Himalayas to experiment with methods that can generate precise height measurements from the two altimeters. Over the same spot, ranging errors due to slope, volume scattering and radar penetration can be common between repeat cycles, and may be reduced by differencing successive heights. We retracked radar waveforms and classify the surfaces using the SRTM-derived elevations. The effects of terrain and slope are reduced by fitting a surface to the height measurements from repeat cycles. We remove outlier heights and apply a smoothing filter to form final time series of glacier elevation change at the selected sites, which are compared with the results from ICESat (note the different mission times). Because TP and Jason-2 measure height changes every 10 days, clear annual and inter-annual oscillations of glacier heights are present in the resulting time series, in comparison to the unevenly sampled height changes from ICESat that do not show such oscillations. The rates of glacier elevation change from T/P and Jason-2 are mostly negative, but vary with locations and heights.
Mathews, Robin; Peterson, Eric D; Li, Shuang; Roe, Matthew T; Glickman, Seth W; Wiviott, Stephen D; Saucedo, Jorge F; Antman, Elliott M; Jacobs, Alice K; Wang, Tracy Y
2011-07-12
Activation of emergency medical services (EMS) is critical for the early triage and treatment of patients experiencing ST-segment-elevation myocardial infarction, yet data regarding EMS use and its association with subsequent clinical care are limited. We performed an observational analysis of 37 634 ST-segment-elevation myocardial infarction patients treated at 372 US hospitals participating in the National Cardiovascular Data Registry Acute Coronary Treatment and Intervention Outcomes Network Registry-Get With the Guidelines between January 2007 and September 2009, and examined independent patient factors associated with EMS transportation versus patient self-transportation. We found that EMS transport was used in only 60% of ST-segment-elevation myocardial infarction patients. Older patients, those living farther from the hospital, and those with hemodynamic compromise were more likely to use EMS transport. In contrast, race, income, and education level did not appear to be associated with the mode of transport. Compared with self-transported patients, EMS-transported patients had significantly shorter delays in both symptom-onset-to-arrival time (median, 89 versus 120 minutes; P<0.0001) and door-to-reperfusion time (median door-to-balloon time, 63 versus 76 minutes; P<0.0001; median door-to-needle time, 23 versus 29 minutes; P<0.0001). Emergency medical services transportation to the hospital is underused among contemporary ST-segment-elevation myocardial infarction patients. Nevertheless, use of EMS transportation is associated with substantial reductions in ischemic time and treatment delays. Community education efforts are needed to improve the use of emergency transport as part of system-wide strategies to improve ST-segment-elevation myocardial infarction reperfusion care.
Spatial and temporal characteristics of elevated temperatures in municipal solid waste landfills.
Jafari, Navid H; Stark, Timothy D; Thalhamer, Todd
2017-01-01
Elevated temperatures in waste containment facilities can pose health, environmental, and safety risks because they generate toxic gases, pressures, leachate, and heat. In particular, MSW landfills undergo changes in behavior that typically follow a progression of indicators, e.g., elevated temperatures, changes in gas composition, elevated gas pressures, increased leachate migration, slope movement, and unusual and rapid surface settlement. This paper presents two MSW landfill case studies that show the spatial and time-lapse movements of these indicators and identify four zones that illustrate the transition of normal MSW decomposition to the region of elevated temperatures. The spatial zones are gas front, temperature front, and smoldering front. The gas wellhead temperature and the ratio of CH 4 to CO 2 are used to delineate the boundaries between normal MSW decomposition, gas front, and temperature front. The ratio of CH 4 to CO 2 and carbon monoxide concentrations along with settlement strain rates and subsurface temperatures are used to delineate the smoldering front. In addition, downhole temperatures can be used to estimate the rate of movement of elevated temperatures, which is important for isolating and containing the elevated temperature in a timely manner. Copyright © 2016 Elsevier Ltd. All rights reserved.
Plastic pikas: Behavioural flexibility in low-elevation pikas (Ochotona princeps)
Varner, Johanna; Horns, Joshua J.; Lambert, Mallory S.; Westberg, Elizabeth; Ruff, James; Wolfenberger, Katelyn; Beever, Erik; Dearing, M. Denise
2016-01-01
Behaviour is an important mechanism for accommodating rapid environmental changes. Understanding a species’ capacity for behavioural plasticity is therefore a key, but understudied, aspect of developing tractable conservation and management plans under climate-change scenarios. Here, we quantified behavioural differences between American pikas (Ochotona princeps) living in an atypical, low-elevation habitat versus those living in a more-typical, alpine habitat. With respect to foraging strategy, low-elevation pikas spent more time consuming vegetation and less time caching food for winter, compared to high-elevation pikas. Low-elevation pikas were also far more likely to be detected in forested microhabitats off the talus than their high-elevation counterparts at midday. Finally, pikas living in the atypical habitat had smaller home range sizes compared to those in typical habitat or any previously published home ranges for this species. Our findings indicate that behavioural plasticity likely allows pikas to accommodate atypical conditions in this low-elevation habitat, and that they may rely on critical habitat factors such as suitable microclimate refugia to behaviourally thermoregulate. Together, these results suggest that behavioural adjustments are one important mechanism by which pikas can persist outside of their previously appreciated dietary and thermal niches.
Correction of elevation offsets in multiple co-located lidar datasets
Thompson, David M.; Dalyander, P. Soupy; Long, Joseph W.; Plant, Nathaniel G.
2017-04-07
IntroductionTopographic elevation data collected with airborne light detection and ranging (lidar) can be used to analyze short- and long-term changes to beach and dune systems. Analysis of multiple lidar datasets at Dauphin Island, Alabama, revealed systematic, island-wide elevation differences on the order of 10s of centimeters (cm) that were not attributable to real-world change and, therefore, were likely to represent systematic sampling offsets. These offsets vary between the datasets, but appear spatially consistent within a given survey. This report describes a method that was developed to identify and correct offsets between lidar datasets collected over the same site at different times so that true elevation changes over time, associated with sediment accumulation or erosion, can be analyzed.
Fatigue Behavior of Glass Fiber-Reinforced Polymer Bars after Elevated Temperatures Exposure.
Li, Guanghui; Zhao, Jun; Wang, Zike
2018-06-16
Fiber-reinforced polymer (FRP) bars have been widely applied in civil engineering. This paper presents the results of an experimental study to investigate the tensile fatigue mechanical properties of glass fiber-reinforced polymer (GFRP) bars after elevated temperatures exposure. For this purpose, a total of 105 GFRP bars were conducted for testing. The specimens were exposed to heating regimes of 100, 150, 200, 250, 300 and 350 °C for a period of 0, 1 or 2 h. The GFRP bars were tested with different times of cyclic load after elevated temperatures exposure. The results show that the tensile strength and elastic modulus of GFRP bars decrease with the increase of elevated temperature and holding time, and the tensile strength of GFRP bars decreases obviously by 19.5% when the temperature reaches 250 °C. Within the test temperature range, the tensile strength of GFRP bars decreases at most by 28.0%. The cyclic load accelerates the degradation of GFRP bars after elevated temperature exposure. The coupling of elevated temperature and holding time enhance the degradation effect of cyclic load on GFRP bars. The tensile strength of GFRP bars after elevated temperatures exposure at 350 °C under cyclic load is reduced by 50.5% compared with that at room temperature and by 36.3% compared with that after exposing at 350 °C without cyclic load. In addition, the elastic modulus of GFRP bars after elevated temperatures exposure at 350 °C under cyclic load is reduced by 17.6% compared with that at room temperature and by 6.0% compared with that after exposing at 350 °C without cyclic load.
Baygin, Mehmet; Karakose, Mehmet
2013-01-01
Nowadays, the increasing use of group elevator control systems owing to increasing building heights makes the development of high-performance algorithms necessary in terms of time and energy saving. Although there are many studies in the literature about this topic, they are still not effective enough because they are not able to evaluate all features of system. In this paper, a new approach of immune system-based optimal estimate is studied for dynamic control of group elevator systems. The method is mainly based on estimation of optimal way by optimizing all calls with genetic, immune system and DNA computing algorithms, and it is evaluated with a fuzzy system. The system has a dynamic feature in terms of the situation of calls and the option of the most appropriate algorithm, and it also adaptively works in terms of parameters such as the number of floors and cabins. This new approach which provides both time and energy saving was carried out in real time. The experimental results comparatively demonstrate the effects of method. With dynamic and adaptive control approach in this study carried out, a significant progress on group elevator control systems has been achieved in terms of time and energy efficiency according to traditional methods. PMID:23935433
Niles, Nathaniel W; Conley, Sheila M; Yang, Rayson C; Vanichakarn, Pantila; Anderson, Tamara A; Butterly, John R; Robb, John F; Jayne, John E; Yanofsky, Norman N; Proehl, Jean A; Guadagni, Donald F; Brown, Jeremiah R
2010-01-01
Rural ST-segment elevation myocardial infarction (STEMI) care networks may be particularly disadvantaged in achieving a door-to-balloon time (D2B) of less than or equal to 90 minutes recommended in current guidelines. ST-ELEVATION MYOCARDIAL INFARCTION PROCESS UPGRADE PROJECT: A multidisciplinary STEMI process upgrade group at a rural percutaneous coronary intervention center implemented evidence-based strategies to reduce time to electrocardiogram (ECG) and D2B, including catheterization laboratory activation triggered by either a prehospital ECG demonstrating STEMI or an emergency department physician diagnosing STEMI, single-call catheterization laboratory activation, catheterization laboratory response time less than or equal to 30 minutes, and prompt data feedback. An ongoing regional STEMI registry was used to collect process time intervals, including time to ECG and D2B, in a consecutive series of STEMI patients presenting before (group 1) and after (group 2) strategy implementation. Significant reductions in time to first ECG in the emergency department and D2B were seen in group 2 compared with group 1. Important improvement in the process of acute STEMI patient care was accomplished in the rural percutaneous coronary intervention center setting by implementing evidence-based strategies. Copyright © 2010 Elsevier Inc. All rights reserved.
Temperature elevation in the fetus from electromagnetic exposure during magnetic resonance imaging
NASA Astrophysics Data System (ADS)
Kikuchi, Satoru; Saito, Kazuyuki; Takahashi, Masaharu; Ito, Koichi
2010-04-01
This study computationally assessed the temperature elevations due to electromagnetic wave energy deposition during magnetic resonance imaging in non-pregnant and pregnant woman models. We used a thermal model with thermoregulatory response of the human body for our calculations. We also considered the effect of blood temperature variation on body core temperature. In a thermal equilibrium state, the temperature elevations in the intrinsic tissues of the woman and fetal tissues were 0.85 and 0.61 °C, respectively, at a whole-body averaged specific absorption rate of 2.0 W kg-1, which is the restriction value of the International Electrotechnical Commission for the normal operating mode. As predicted, these values are below the temperature elevation of 1.5 °C that is expected to be teratogenic. However, these values exceeded the recommended temperature elevation limit of 0.5 °C by the International Commission on Non-Ionizing Radiation Protection. We also assessed the irradiation time required for a temperature elevation of 0.5 °C at the aforementioned specific absorption rate. As a result, the calculated irradiation time was 40 min.
Pravosudov, Vladimir V
2003-12-22
It is widely assumed that chronic stress and corresponding chronic elevations of glucocorticoid levels have deleterious effects on animals' brain functions such as learning and memory. Some animals, however, appear to maintain moderately elevated levels of glucocorticoids over long periods of time under natural energetically demanding conditions, and it is not clear whether such chronic but moderate elevations may be adaptive. I implanted wild-caught food-caching mountain chickadees (Poecile gambeli), which rely at least in part on spatial memory to find their caches, with 90-day continuous time-release corticosterone pellets designed to approximately double the baseline corticosterone levels. Corticosterone-implanted birds cached and consumed significantly more food and showed more efficient cache recovery and superior spatial memory performance compared with placebo-implanted birds. Thus, contrary to prevailing assumptions, long-term moderate elevations of corticosterone appear to enhance spatial memory in food-caching mountain chickadees. These results suggest that moderate chronic elevation of corticosterone may serve as an adaptation to unpredictable environments by facilitating feeding and food-caching behaviour and by improving cache-retrieval efficiency in food-caching birds.
A 19-year radar altimeter elevation change time-series of the East and West Antarctic ice sheets
NASA Astrophysics Data System (ADS)
Sundal, A. V.; Shepherd, A.; Wingham, D.; Muir, A.; Mcmillan, M.; Galin, N.
2012-12-01
We present 19 years of continuous radar altimeter observations of the East and West Antarctic ice sheets acquired by the ERS-1, ERS-2, and ENVISAT satellites between May 1992 and September 2010. Time-series of surface elevation change were developed at 39,375 crossing points of the satellite orbit ground tracks using the method of dual cycle crossovers (Zwally et al., 1989; Wingham et al., 1998). In total, 46.5 million individual measurements were included in the analysis, encompassing 74 and 76 % of the East and West Antarctic ice sheet, respectively. The satellites were cross-calibrated by calculating differences between elevation changes occurring during periods of mission overlap. We use the merged time-series to explore spatial and temporal patterns of elevation change and to characterise and quantify the signals of Antarctic ice sheet imbalance. References: Wingham, D., Ridout, A., Scharroo, R., Arthern, R. & Shum, C.K. (1998): Antarctic elevation change from 1992 to 1996. Science, 282, 456-458. Zwally, H. J., Brenner, A. C., Major, J. A., Bindschadler, R. A. & Marsh, J. G. (1989): Growth of Greenland ice-sheet - measurements. Science, 246, 1587-1589.
Interpretation of ICESat-Derived Elevation Change on the Malaspina-Seward Glacier
NASA Astrophysics Data System (ADS)
Sauber, J.; Ramage, J.; Kopczynski, S.; Muskett, R.
2005-12-01
In this study, we report and interpret ICESat-derived short-term variability in surface elevation in the snow accumulation region of the Seward-Malaspina Glacier, one of the largest glacier systems in southern Alaska. The Seward-Malaspina complex consists of an extensive icefield, the upper Seward Glacier, and a narrower lower outlet glacier (lower Seward) through which ice drains to the enormous piedmont of the Malaspina Glacier. Although the upper Seward is just 80 km north of the Gulf of Alaska it has an environment more continental than maritime because of shielding afforded by high mountains to the south [Sharp, 1951]. The Malaspina Glacier by contrast lies completely within the moist maritime environment of the southern Alaska coast. In an earlier study of the Malaspina Glacier, we reported elevation differences between ICESat Laser 1-3 observations (February 2003 - November 2004) and a Shuttle Radar Topography Mission (SRTM)-derived DEM from February 2000 [Sauber et al., 2005]. Elevation decreases of up to 20-25 m over a 3-4 year time period were observed across the folded loop moraine on the southern portion of the piedmont lobe of the Malaspina Glacier. For the western portion of the Upper Seward we will estimate elevation change over a comparable time period by using an X-band InSAR-derived DEM from Intermap Tech. (Sept. 2000) and ICESat-derived elevations. Early field measurements (1945-1949) from the Upper Seward Glacier indicated an average annual net surplus of 75 cm water equivalent in the Upper Seward basin [Sharp, 1951]. However, even over this short time period, Sharp [1951] found large interannual variability in net accumulation of 41-168 cm. To further constrain and understand surface changes, we examined ICESat-derived elevations from a variable set of repeated ICESat upper Seward profiles made between Feb. 2003 and May 2005. Additionally we compared the elevation change profiles to snowmelt timing and ablation season length derived from the Special Sensor Microwave Imager (SSM/I) 37 GHz brightness temperatures for 2000-2004 using the approach of Ramage and Isacks (2003). We found the largest elevation increase between Oct 2003 and late Feb./March 2004 (3-4 m over a flat region of the upper Seward at 1740 m), little discernible elevation change occurred between March and May 2004, and about 2 m of elevation decrease occurred at 1750 m between May and Oct. 2004. The elevation increase of 3-4 m at 1740 m in the upper Seward occurred after refreezing started in August 2003 and before the snowmelt onset in mid to late April 2004. Ramage and Isacks, J. Glaciol., 2003. Sauber et al., Geophys. Res. Lett., in press, 2005. Sharp, Geol. Soc. Am.,1951.
Domenici, Paolo; Torres, Rodrigo; Manríquez, Patricio H
2017-02-15
Recent work has shown that the behaviour of marine organisms can be affected by elevated P CO 2 , although little is known about the effect of multiple stressors. We therefore investigated the effect of elevated P CO 2 and temperature on locomotion and behaviour during prey searching in the marine gastropod Concholepas concholepas , a predator characteristic of the southeastern Pacific coast. Movement duration, decision time, route finding and lateralization were measured using a T-maze tank with a prey positioned behind a barrier. Four treatments, representing present day and near-future scenarios of ocean acidification and warming were used in rearing the individuals for 6 months. Regardless of the treatment, no significant differences were found in relative and absolute lateralization before and after exposure for 6 months. However, relative lateralization was not repeatable for animals tested after 6 months at elevated P CO 2 at both experimental temperatures, whereas it was repeatable in individuals kept at the present day level of P CO 2 We suggest that these effects may be related to a behavioural malfunction caused by elevated P CO 2 Movement duration, decision time and route finding were not repeatable. However, movement duration and decision time increased and route finding decreased in elevated P CO 2 (at 15°C), suggesting that elevated P CO 2 has negative effects on the locomotor and sensory performance of C. concholepas in the presence of a prey odour, thereby decreasing their ability to forage efficiently. © 2017. Published by The Company of Biologists Ltd.
Buckley, Lauren B; Nufio, César R; Kirk, Evan M; Kingsolver, Joel G
2015-06-22
Annual species may increase reproduction by increasing adult body size through extended development, but risk being unable to complete development in seasonally limited environments. Synthetic reviews indicate that most, but not all, species have responded to recent climate warming by advancing the seasonal timing of adult emergence or reproduction. Here, we show that 50 years of climate change have delayed development in high-elevation, season-limited grasshopper populations, but advanced development in populations at lower elevations. Developmental delays are most pronounced for early-season species, which might benefit most from delaying development when released from seasonal time constraints. Rearing experiments confirm that population, elevation and temperature interact to determine development time. Population differences in developmental plasticity may account for variability in phenological shifts among adults. An integrated consideration of the full life cycle that considers local adaptation and plasticity may be essential for understanding and predicting responses to climate change. © 2015 The Author(s) Published by the Royal Society. All rights reserved.
Study on real-time elevator brake failure predictive system
NASA Astrophysics Data System (ADS)
Guo, Jun; Fan, Jinwei
2013-10-01
This paper presented a real-time failure predictive system of the elevator brake. Through inspecting the running state of the coil by a high precision long range laser triangulation non-contact measurement sensor, the displacement curve of the coil is gathered without interfering the original system. By analyzing the displacement data using the diagnostic algorithm, the hidden danger of the brake system can be discovered in time and thus avoid the according accident.
Structural efficiencies of various aluminum, titanium, and steel alloys at elevated temperatures
NASA Technical Reports Server (NTRS)
Heimerl, George J; Hughes, Philip J
1953-01-01
Efficient temperature ranges are indicated for two high-strength aluminum alloys, two titanium alloys, and three steels for some short-time compression-loading applications at elevated temperatures. Only the effects of constant temperatures and short exposure to temperature are considered, and creep is assumed not to be a factor. The structural efficiency analysis is based upon preliminary results of short-time elevated-temperature compressive stress-strain tests of the materials. The analysis covers strength under uniaxial compression, elastic stiffness, column buckling, and the buckling of long plates in compression or in shear.
Sander, Laura D.; Newell, Kevin; Ssebbowa, Paschal; Serwadda, David; Quinn, Thomas C.; Gray, Ronald H.; Wawer, Maria J.; Mondo, George; Reynolds, Steven
2014-01-01
Objectives To assess the prevalence of hypertension, elevated blood pressure and cardiovascular risk factors among HIV-positive individuals in rural Rakai District, Uganda. Methods We assessed 426 HIV-positive individuals in Rakai, Uganda from 2007 to 2010. Prevalence of hypertension and elevated blood pressure assessed by clinical measurement was compared to clinician-recorded hypertension in case report forms. Multiple logistic regression and z-tests were used to examine the association of hypertension and elevated blood pressure with age, sex, body mass index, CD4 cell count, and anti-retroviral treatment (ART) use. For individuals on anti-hypertensives, medication utilization was reviewed. Results The prevalence of hypertension (two elevated blood pressure readings at different time points) was 8.0% (95% CI: 5.4–10.6%), and that of elevated blood pressure (one elevated blood pressure reading) was 26.3% (95% CI: 22.1–30.5%). Age ≥50 years and higher body mass index were positively associated with elevated blood pressure. ART use, time on ART, and CD4 cell count were not associated with hypertension. 83% of subjects diagnosed with hypertension were on anti-hypertensive medications, most commonly beta-blockers and calcium channel blockers. Conclusions Hypertension is common among HIV-positive individuals in rural Uganda. PMID:25430847
Plastic pikas: Behavioural flexibility in low-elevation pikas (Ochotona princeps).
Varner, Johanna; Horns, Joshua J; Lambert, Mallory S; Westberg, Elizabeth; Ruff, James S; Wolfenberger, Katelyn; Beever, Erik A; Dearing, M Denise
2016-04-01
Behaviour is an important mechanism for accommodating rapid environmental changes. Understanding a species' capacity for behavioural plasticity is therefore a key, but understudied, aspect of developing tractable conservation and management plans under climate-change scenarios. Here, we quantified behavioural differences between American pikas (Ochotona princeps) living in an atypical, low-elevation habitat versus those living in a more-typical, alpine habitat. With respect to foraging strategy, low-elevation pikas spent more time consuming vegetation and less time caching food for winter, compared to high-elevation pikas. Low-elevation pikas were also far more likely to be detected in forested microhabitats off the talus than their high-elevation counterparts at midday. Finally, pikas living in the atypical habitat had smaller home range sizes compared to those in typical habitat or any previously published home ranges for this species. Our findings indicate that behavioural plasticity likely allows pikas to accommodate atypical conditions in this low-elevation habitat, and that they may rely on critical habitat factors such as suitable microclimate refugia to behaviourally thermoregulate. Together, these results suggest that behavioural adjustments are one important mechanism by which pikas can persist outside of their previously appreciated dietary and thermal niches. Copyright © 2016 Elsevier B.V. All rights reserved.
Stiefel, Eric C.; Field, Larry; Replogle, William; McIntyre, Louis; Igboechi, Oduche; Savoie, Felix H.
2016-01-01
Background: Over the past 30 years, there has been a dramatic increase in the prevalence of childhood obesity and hypertension in the United States. The prevalence of these diagnoses among individuals participating in school-sanctioned sports has not been clearly defined. Purpose: To identify the prevalence of obesity and elevated blood pressure (BP) among student athletes and investigate associations between race, sex, type and number of sports played, and the prevalence of these diseases. Study Design: Cross-sectional study; Level of evidence, 3. Methods: Pre–sports participation medical examinations (N = 7705) performed between 2009 and 2013 were reviewed to identify the prevalence of obesity and elevated BP and examine relationships between the type of sports played, participation in multiple sports versus a single sport, and the athlete’s body weight and body mass index (BMI). Results: The prevalence of obesity was 23.5%. There was a significant association (P < .001) between the number of sports played by the student and BMI. The risk of obesity among single-sport athletes was more than 2-fold the risk (relative risk [RR], 2.13) compared with ≥3-sport athletes and 1.42 times greater compared with 2-sport athletes (RR, 1.42). The prevalence of elevated BP was 21.2%. There was a significant association (P < .001) between the number of sports played by the student and elevated BP. The risk of elevated BP among single-sport athletes was 1.59 times greater (RR, 1.59) than ≥3-sport athletes and 1.30 times greater compared with 2-sport athletes (RR, 1.30). Finally, obese students were 2.40 times more likely to have elevated BP compared with nonobese students (P < .001). Conclusion: The result of this study confirms the progressive nature of the obesity epidemic and identifies the contribution of obesity to the worsening cardiometabolic profiles in student athletes. The study also identifies that participation in multiple sports and running sports decreases the individual’s risk for obesity and hypertension. Clinical Relevance: The present study emphasizes the importance of screening for obesity and elevated blood pressure during the athlete’s preparticipation physical examination. PMID:26962540
McGarry, Bryony L; Rogers, Harriet J; Knight, Michael J; Jokivarsi, Kimmo T; Sierra, Alejandra; Gröhn, Olli Hj; Kauppinen, Risto A
2016-08-01
Quantitative T2 relaxation magnetic resonance imaging allows estimation of stroke onset time. We aimed to examine the accuracy of quantitative T1 and quantitative T2 relaxation times alone and in combination to provide estimates of stroke onset time in a rat model of permanent focal cerebral ischemia and map the spatial distribution of elevated quantitative T1 and quantitative T2 to assess tissue status. Permanent middle cerebral artery occlusion was induced in Wistar rats. Animals were scanned at 9.4T for quantitative T1, quantitative T2, and Trace of Diffusion Tensor (Dav) up to 4 h post-middle cerebral artery occlusion. Time courses of differentials of quantitative T1 and quantitative T2 in ischemic and non-ischemic contralateral brain tissue (ΔT1, ΔT2) and volumes of tissue with elevated T1 and T2 relaxation times (f1, f2) were determined. TTC staining was used to highlight permanent ischemic damage. ΔT1, ΔT2, f1, f2, and the volume of tissue with both elevated quantitative T1 and quantitative T2 (V(Overlap)) increased with time post-middle cerebral artery occlusion allowing stroke onset time to be estimated. V(Overlap) provided the most accurate estimate with an uncertainty of ±25 min. At all times-points regions with elevated relaxation times were smaller than areas with Dav defined ischemia. Stroke onset time can be determined by quantitative T1 and quantitative T2 relaxation times and tissue volumes. Combining quantitative T1 and quantitative T2 provides the most accurate estimate and potentially identifies irreversibly damaged brain tissue. © 2016 World Stroke Organization.
NASA Astrophysics Data System (ADS)
Elmore, A. J.; Cadol, D. D.; Palinkas, C. M.; Engelhardt, K. A.
2014-12-01
The maintenance of marsh platform elevation under sea level rise is dependent on sedimentation and biomass conversion to soil organic material. These physical and biological processes interact within the tidal zone, resulting in elevation-dependent processes contributing to marsh accretion. Here we explore spatial pattern in plant litter, a variable related to productivity, to understand its role in physical and biological interactions in a freshwater marsh. Plant litter that persists through the dormant season has an extended period of influence on ecosystem processes. We conducted a field and remote sensing analysis of plant litter height, biomass, vertical cover, and stem density (collectively termed plant litter structure) at a tidal freshwater marsh located along the Potomac River estuary. We completed two years of repeat RTK GPS surveys with corresponding measurements of litter height (over 2000 observations) to train a non-parametric random forest decision tree to predict litter height. LiDAR and field observations show that plant litter height increases with increasing elevation, although important deviations from this relationship are apparent. These spatial patterns exhibit stability from year to year and lead to corresponding patterns in soil organic matter content, revealed by loss on ignition of surface sediments. The amount of mineral material embedded within plant litter decreases with increasing elevation, representing an important trade-off with litter structure. Therefore, at low elevations where litter structure is short and sparse, the role of plant litter is to capture sediment; at high elevations where litter structure is tall and dense, litter contributes organic matter to soil development. Despite these tradeoffs, changes in elevation over time are consistent across elevation, with only small positive differences in elevation gain over time at elevations where the most sediment is deposited or where litter exhibits the most biomass.
Effects of Oritavancin on Coagulation Tests in the Clinical Laboratory.
Belley, Adam; Robson, Richard; Francis, John L; Adcock, Dorothy M; Tiefenbacher, Stefan; Rubino, Christopher M; Moeck, Greg; Sylvester, David; Dudley, Michael N; Loutit, Jeffery
2017-02-01
Previous studies have shown that some lipoglycopeptide and lipopeptide antimicrobial agents may cause falsely elevated values for some phospholipid-dependent coagulation tests. The effect of oritavancin, a lipoglycopeptide antibiotic, on coagulation test results was explored using pooled human plasma samples spiked with drug and in a clinical study after an infusion of a single 1,200-mg intravenous dose of oritavancin in normal healthy volunteers. Pooled plasma with oritavancin added ex vivo showed concentration-dependent prolongation of prothrombin time/international normalized ratio (PT/INR), activated partial thromboplastin time (aPTT), and dilute Russell viper venom time (DRVVT) test results. In contrast, oritavancin had no effect on the activated protein C resistance assay, chromogenic anti-factor Xa assay (anti-FXa), thrombin time, and an immunoassay for the laboratory diagnosis of heparin-induced thrombocytopenia. In participants that received a single dose of oritavancin, elevations in PT/INR result, aPTT, DRVVT, activated clotting time, and silica clotting time occurred, with the maximum times to resolution of test interference determined to be 12, 120, 72, 24, and 18 h, respectively. The anti-FXa assay was unaffected, whereas transient elevations in D dimer levels were observed in 30% of participants, with a maximum time to resolution of 72 h. Although oritavancin has no impact on the coagulation system in vivo, a single dose of oritavancin can produce falsely elevated values of some coagulation tests used to monitor hemostasis. The interference of oritavancin on affected tests is transient, and the test results revert to normal ranges within specified times after dosing. Copyright © 2017 American Society for Microbiology.
Effects of Oritavancin on Coagulation Tests in the Clinical Laboratory
Robson, Richard; Francis, John L.; Adcock, Dorothy M.; Tiefenbacher, Stefan; Rubino, Christopher M.; Moeck, Greg; Sylvester, David; Dudley, Michael N.; Loutit, Jeffery
2016-01-01
ABSTRACT Previous studies have shown that some lipoglycopeptide and lipopeptide antimicrobial agents may cause falsely elevated values for some phospholipid-dependent coagulation tests. The effect of oritavancin, a lipoglycopeptide antibiotic, on coagulation test results was explored using pooled human plasma samples spiked with drug and in a clinical study after an infusion of a single 1,200-mg intravenous dose of oritavancin in normal healthy volunteers. Pooled plasma with oritavancin added ex vivo showed concentration-dependent prolongation of prothrombin time/international normalized ratio (PT/INR), activated partial thromboplastin time (aPTT), and dilute Russell viper venom time (DRVVT) test results. In contrast, oritavancin had no effect on the activated protein C resistance assay, chromogenic anti-factor Xa assay (anti-FXa), thrombin time, and an immunoassay for the laboratory diagnosis of heparin-induced thrombocytopenia. In participants that received a single dose of oritavancin, elevations in PT/INR result, aPTT, DRVVT, activated clotting time, and silica clotting time occurred, with the maximum times to resolution of test interference determined to be 12, 120, 72, 24, and 18 h, respectively. The anti-FXa assay was unaffected, whereas transient elevations in D dimer levels were observed in 30% of participants, with a maximum time to resolution of 72 h. Although oritavancin has no impact on the coagulation system in vivo, a single dose of oritavancin can produce falsely elevated values of some coagulation tests used to monitor hemostasis. The interference of oritavancin on affected tests is transient, and the test results revert to normal ranges within specified times after dosing. PMID:27956417
NASA Astrophysics Data System (ADS)
Schenk, A. F.; Csatho, B. M.; van den Broeke, M.; Kuipers Munneke, P.
2015-12-01
This paper reports about important upgrades of the Greenland Ice Sheet (GrIS) surface elevation and elevation-change database obtained with our Surface Elevation And Change detection (SERAC) software suite. We have developed SERAC to derive information from laser altimetry data, particularly time series of elevation changes and their partitioning into changes caused by ice dynamics. This allows direct investigation of ice dynamic processes that is much needed for improving the predictive power of ice sheet models. SERAC is different from most other change detection methods. It is based on detecting changes of surface patches, about 1 km by 1 km in size, rather than deriving elevation changes from individual laser points. The current database consists of ~100,000 time series with satellite laser altimetry data from ICESat, airborne laser observations obtained by NASA's Airborne Topographic Mapper (ATM) and the Land, Vegetation and Ice Sensor (LVIS). The upgrade is significant, because not only new observations from 2013 and 2014 have been added but also a number of improvements lead to a more comprehensive and consistent record of elevation-changes. First, we used the model that gives in addition to ice sheet also information about ice caps and glaciers (Rastner et al., 2012) for deciding if a laser point is on the ice sheet or ice cap. Then we added small gaps that exist in the ICESat GLA12 data set because the ice sheet mask is not wide enough. The new database is now more complete and will facilitate more accurate comparisons of mass balance studies obtained from the Gravity Recovery and Climate Experiment system (GRACE). For determining the part of a time series caused by ice dynamics we used the new firn compaction model and Surface Mass Balance (SMB) estimates from RACMO2.3. The new database spans the time period from 1993 to 2014. Adding new observations amounts to a spatial densification of the old record and at the same time extends the time domain by two years. Our presentation will show the improvement of the reconstruction of the total changes, those caused by SMB and ice dynamic during the ICESat mission (2003-2009). Moreover we will review changes on scales from individual outlet glaciers to drainage basins and the entire ice sheet.
Giant panda foraging and movement patterns in response to bamboo shoot growth.
Zhang, Mingchun; Zhang, Zhizhong; Li, Zhong; Hong, Mingsheng; Zhou, Xiaoping; Zhou, Shiqiang; Zhang, Jindong; Hull, Vanessa; Huang, Jinyan; Zhang, Hemin
2018-03-01
Diet plays a pivotal role in dictating behavioral patterns of herbivorous animals, particularly specialist species. The giant panda (Ailuropoda melanoleuca) is well-known as a bamboo specialist. In the present study, the response of giant pandas to spatiotemporal variation of bamboo shoots was explored using field surveys and GPS collar tracking. Results show the dynamics in panda-bamboo space-time relationships that have not been previously articulated. For instance, we found a higher bamboo stump height of foraged bamboo with increasing elevation, places where pandas foraged later in spring when bamboo shoots become more fibrous and woody. The time required for shoots to reach optimum height for foraging was significantly delayed as elevation increased, a pattern which corresponded with panda elevational migration patterns beginning from the lower elevational end of Fargesia robusta distribution and gradually shifting upward until the end of the shooting season. These results indicate that giant pandas can respond to spatiotemporal variation of bamboo resources, such as available shoots. Anthropogenic interference of low-elevation F. robusta habitat should be mitigated, and conservation attention and increased monitoring should be given to F. robusta areas at the low- and mid-elevation ranges, particularly in the spring shooting season.
Early Elevation of Serum TNFα is Associated with Poor Outcome in Subarachnoid Hemorrhage
Chou, Sherry HY.; Feske, Steven K.; Atherton, Juli; Konigsberg, Rachael G.; De Jager, Philip L.; Du, Rose; Lo, Eng H.; Ning, MingMing
2013-01-01
Objective Subarachnoid hemorrhage (SAH) is associated with inflammation which may mediate poor outcome in SAH. We hypothesize that elevated serum tumor necrosis factor-alpha (TNFα) and interleukin-6 (IL-6) are associated with vasospasm and poor outcome in SAH. Methods In 52 consecutive SAH subjects, we compared TNFα and IL-6 levels on post-SAH days 0–1, 2–3, 4–5, 6–8, and 10–14 with respect to vasospasm and to poor outcome at 3- and 6-months. Vasospasm was defined as >50% reduction in vessel caliber on angiography. Poor outcome was defined as modified Rankin score >2. Results Elevated TNFα on post-SAH days 2–3 was associated with poor 3-month outcome (p=0.0004). Global elevation of TNFα over time (post-SAH days 0–14) was independently associated with poor 3-month outcome after adjusting for Hunt-and-Hess grade and age (p=0.02). Neither cross-sectional nor IL-6 levels over time were associated with outcome. Neither TNFα nor IL-6 levels were associated with vasospasm. Conclusions Elevation in serum TNFα on post-SAH days 2–3 and global elevation of TNFα over time are associated with poor outcome but not with angiographic vasospasm in this small cohort. Future studies are needed to define the role of TNFα in SAH-related brain injury and its potential as a SAH outcome biomarker. PMID:22918199
Koifman, Edward; Beigel, Roy; Iakobishvili, Zaza; Shlomo, Nir; Biton, Yitschak; Sabbag, Avi; Asher, Elad; Atar, Shaul; Gottlieb, Shmuel; Alcalai, Ronny; Zahger, Doron; Segev, Amit; Goldenberg, Ilan; Strugo, Rafael; Matetzky, Shlomi
2017-01-01
Ischemic time has prognostic importance in ST-elevation myocardial infarction patients. Mobile intensive care unit use can reduce components of total ischemic time by appropriate triage of ST-elevation myocardial infarction patients. Data from the Acute Coronary Survey in Israel registry 2000-2010 were analyzed to evaluate factors associated with mobile intensive care unit use and its impact on total ischemic time and patient outcomes. The study comprised 5474 ST-elevation myocardial infarction patients enrolled in the Acute Coronary Survey in Israel registry, of whom 46% ( n=2538) arrived via mobile intensive care units. There was a significant increase in rates of mobile intensive care unit utilization from 36% in 2000 to over 50% in 2010 ( p<0.001). Independent predictors of mobile intensive care unit use were Killip>1 (odds ratio=1.32, p<0.001), the presence of cardiac arrest (odds ratio=1.44, p=0.02), and a systolic blood pressure <100 mm Hg (odds ratio=2.01, p<0.001) at presentation. Patients arriving via mobile intensive care units benefitted from increased rates of primary reperfusion therapy (odds ratio=1.58, p<0.001). Among ST-elevation myocardial infarction patients undergoing primary reperfusion, those arriving by mobile intensive care unit benefitted from shorter median total ischemic time compared with non-mobile intensive care unit patients (175 (interquartile range 120-262) vs 195 (interquartile range 130-333) min, respectively ( p<0.001)). Upon a multivariate analysis, mobile intensive care unit use was the most important predictor in achieving door-to-balloon time <90 min (odds ratio=2.56, p<0.001) and door-to-needle time <30 min (odds ratio=2.96, p<0.001). One-year mortality rates were 10.7% in both groups (log-rank p-value=0.98), however inverse propensity weight model, adjusted for significant differences between both groups, revealed a significant reduction in one-year mortality in favor of the mobile intensive care unit group (odds ratio=0.79, 95% confidence interval (0.66-0.94), p=0.01). Among patients with ST-elevation myocardial infarction, the utilization of mobile intensive care units is associated with increased rates of primary reperfusion, a reduction in the time interval to reperfusion, and a reduction in one-year adjusted mortality.
Del Bene, Victor A; Arce Rentería, Miguel; Maiman, Moshe; Slugh, Mitch; Gazzola, Deana M; Nadkarni, Siddhartha S; Barr, William B
2017-07-01
The Minnesota Multiphasic Personality Inventory-2-Restructured Form (MMPI-2-RF) is a self-report instrument, previously shown to differentiate patients with epileptic seizures (ES) and psychogenic non-epileptic seizures (PNES). At present, the odds of MMPI-2-RF scale elevations in PNES patients, as well as the diagnostic predictive value of such scale elevations, remain largely unexplored. This can be of clinical utility, particularly when a diagnosis is uncertain. After looking at mean group differences, we applied contingency table derived odds ratios to a sample of ES (n=92) and PNES (n=77) patients from a video EEG (vEEG) monitoring unit. We also looked at the positive and negative predictive values (PPV, NPV), as well as the false discovery rate (FDR) and false omission rate (FOR) for scales found to have increased odds of elevation in PNES patients. This was completed for the overall sample, as well as the sample stratified by sex. The odds of elevations related to somatic concerns, negative mood, and suicidal ideation in the PNES sample ranged from 2 to 5 times more likely. Female PNES patients had 3-6 times greater odds of such scale elevations, while male PNES patients had odds of 5-15 times more likely. PPV rates ranged from 53.66% to 84.62%, while NPV rates ranged from 47.52% to 90.91%. FDR across scales ranged from 15.38% to 50%, while the FOR ranged from 9.09% to 52.47%. Consistent with prior research, PNES patients have greater odds of MMPI-2-RF scale elevations, particularly related to somatic concerns and mood disturbance. Female PNES patients endorsed greater emotional distress, including endorsement of suicide related items. Elevations of these scales could aid in differentiating PNES from ES patients, although caution is warranted due to the possibility of both false positives and the incorrect omissions of PNES cases. Copyright © 2017 Elsevier Inc. All rights reserved.
Kulkarni, Malavika; Chuchendra, L. S.; Bhavya, P. J.
2018-01-01
Background: The onset time of neuromuscular blockade is a crucial time associated with the risk of hypoxia and pulmonary aspiration. Various strategies have been undertaken to shorten this onset time. Therefore, we investigated the effects of bolus of 20 ml saline followed by limb elevation after administration of rocuronium in a dose of 0.6 mg/kg to study the onset time. Methodology: Thirty patients were randomly allocated to the bolus saline group or control group. General anesthesia was induced and maintained with fentanyl and propofol. Rocuronium 0.6 mg/kg intravenous (IV) was administered followed by 20 ml saline bolus and limb elevation in the study group compared to administration of 0.6 mg/kg in a running drip only in the control. Onset of neuromuscular block was assessed by acceleromyography at the adductor pollicis muscle with train-of-four stimulation. Results: The lag time was shorter in bolus group (34 s median) than in control group (45 s median), P < 0.017. The onset time was shorter in bolus group (55 s median) than in control group (110 s median), P < 0.001. The T1 recovery to 25% was longer in bolus group (42 min median) than in control group (39 min median) which was statistically not significant. Conclusion: Rocuronium 0.6 mg/kg IV followed by bolus 20 ml saline and concomitant limb elevation resulted in shorter lag time, faster onset of neuromuscular blockade, good intubating conditions without prolonging clinical duration of action when compared to the control. PMID:29628555
TV Watching and Computer Use in U.S. Youth Aged 12-15, 2012. NCHS Data Brief. Number 157
ERIC Educational Resources Information Center
Herrick, Kirsten A.; Fakhouri, Tala H. I.; Carlson, Susan A.; Fulton, Janet E.
2014-01-01
Excessive screen-time behaviors, such as using a computer and watching TV, for more than 2 hours daily have been linked with elevated blood pressure, elevated serum cholesterol, and being overweight or obese among youth. Additionally, screen-time behavior established in adolescence has been shown to track into adulthood. The National Heart, Lung,…
NASA Astrophysics Data System (ADS)
Wang, Tingting; Sun, Fubao; Ge, Quansheng; Kleidon, Axel; Liu, Wenbin
2018-02-01
Although gridded air temperature data sets share much of the same observations, different rates of warming can be detected due to different approaches employed for considering elevation signatures in the interpolation processes. Here we examine the influence of varying spatiotemporal distribution of sites on surface warming in the long-term trend and over the recent warming hiatus period in China during 1951-2015. A suspicious cooling trend in raw interpolated air temperature time series is found in the 1950s, and 91% of which can be explained by the artificial elevation changes introduced by the interpolation process. We define the regression slope relating temperature difference and elevation difference as the bulk lapse rate of -5.6°C/km, which tends to be higher (-8.7°C/km) in dry regions but lower (-2.4°C/km) in wet regions. Compared to independent experimental observations, we find that the estimated monthly bulk lapse rates work well to capture the elevation bias. Significant improvement can be achieved in adjusting the interpolated original temperature time series using the bulk lapse rate. The results highlight that the developed bulk lapse rate is useful to account for the elevation signature in the interpolation of site-based surface air temperature to gridded data sets and is necessary for avoiding elevation bias in climate change studies.
DOT National Transportation Integrated Search
2009-01-01
The establishment of accurate and reliable vertical elevations in Louisiana is : exceedingly critical due to the substantial impact on flood control, hurricane : protection projects, and navigation projects of rapidly changing vertical elevations due...
Background-Source Cosmic-Photon Elevation Scaling and Cosmic-Neutron/Photon Date Scaling in MCNP6
NASA Astrophysics Data System (ADS)
Tutt, J.; Anderson, C.; McKinney, G.
Cosmic neutron and photon fluxes are known to scale exponentially with elevation. Consequently, cosmic neutron elevation scaling was implemented for use with the background-source option shortly after its introduction into MCNP6, whereby the neutron flux weight factor was adjusted by the elevation scaling factor when the user-specified elevation differed from the selected background.dat grid-point elevation. At the same time, an elevation scaling factor was suggested for the cosmic photon flux, however, cosmic photon elevation scaling is complicated by the fact that the photon background consists of two components: cosmic and terrestrial. Previous versions of the background.dat file did not provide any way to separate these components. With Rel. 4 of this file in 2015, two new columns were added that provide the energy grid and differential cosmic photon flux separately from the total photon flux. Here we show that the cosmic photon flux component can now be scaled independently and combined with the terrestrial component to form the total photon flux at a user-specified elevation in MCNP6. Cosmic background fluxes also scale with the solar cycle due to solar modulation. This modulation has been shown to be nearly sinusoidal over time, with an inverse effect - increased modulation leads to a decrease in cosmic fluxes. This effect was initially included with the cosmic source option in MCNP6 and has now been extended for use with the background source option when: (1) the date is specified in the background.dat file, and (2) when the user specifies a date on the source definition card. A description of the cosmic-neutron/photon date scaling feature will be presented along with scaling results for past and future date extrapolations.
Elevational gradient in clutch size of Red-faced Warblers
Dillon, Kristen G.; Conway, Courtney J.
2015-01-01
Our understanding of life history evolution has benefited from debates regarding the underlying causes, and geographic ubiquity, of spatial patterns in avian clutch sizes. Past studies have revealed that birds lay smaller clutch sizes at higher elevation. However, in most previous studies, investigators have failed to adequately control for elevational differences in breeding phenology. To better understand the elevational gradient in avian clutch size, we need to know how clutch size changes across the entire elevational breeding range of a species (i.e., the shape of the relationship between elevation and clutch size), and whether the elevational gradient in clutch size is merely an artifact of elevational gradients in breeding phenology or breeding season length. We examined the relationship between breeding elevation and clutch size of Red-faced Warblers (Cardellina rubrifrons) along a 1000-m elevational gradient in Arizona. Our objectives were to determine how clutch size changed with elevation, and if the relationship between clutch size and elevation merely reflected elevational changes in breeding season length or phenology. The proportion of 5-egg clutches decreased and the proportion of 3- and 4-egg clutches increased non-linearly with increasing elevation, even after controlling for the elevational gradient in nest initiation date. Thus, average clutch size declined across the elevational breeding range of Red-faced Warblers, but this decline was not due to elevational variation in breeding phenology. Timing of breeding changed, but the duration of the breeding season did not change appreciably across the elevational gradient. Hence, elevational differences in breeding season length or breeding phenology cannot explain why Red-faced Warblers (and perhaps other birds) breeding at higher elevations have smaller clutches.
NASA Astrophysics Data System (ADS)
Su, Xiaoli; Luo, Zhicai; Zhou, Zebing
2018-06-01
Knowledge of backscatter change is important to accurately retrieve elevation change time series from satellite radar altimetry over continental ice sheets. Previously, backscatter coefficients generated in two cases, namely with and without accounting for backscatter gradient (BG), are used. However, the difference between backscatter time series obtained separately in these two cases and its impact on retrieving elevation change are not well known. Here we first compare the mean profiles of the Ku and Ka band backscatter over the Greenland ice sheet (GrIS), with results illustrating that the Ku-band backscatter is 3 ∼ 5 dB larger than that of the Ka band. We then conduct statistic analysis about time series of backscatter formed separately in the above two cases for both Ku and Ka bands over two regions in the GrIS. It is found that the standard deviation of backscatter time series becomes slightly smaller after removing the BG effect, which suggests that the method for the BG correction is effective. Furthermore, the impact on elevation change from backscatter change due to the BG effect is separately assessed for both Ku and Ka bands over the GrIS. We conclude that Ka band altimetry would benefit from a BG induced backscatter analysis (∼10% over region 2). This study may provide a reference to form backscatter time series towards refining elevation change time series from satellite radar altimetry over ice sheets using repeat-track analysis.
NASA Astrophysics Data System (ADS)
O'Leary, Donal S.; Kellermann, Jherime L.; Wayne, Chris
2018-02-01
Anthropogenic climate change is having significant impacts on montane and high-elevation areas globally. Warmer winter temperatures are driving reduced snowpack in the western USA with broad potential impacts on ecosystem dynamics of particular concern for protected areas. Vegetation phenology is a sensitive indicator of ecological response to climate change and is associated with snowmelt timing. Human monitoring of climate impacts can be resource prohibitive for land management agencies, whereas remotely sensed phenology observations are freely available at a range of spatiotemporal scales. Little work has been done in regions dominated by evergreen conifer cover, which represents many mountain regions at temperate latitudes. We used moderate resolution imaging spectroradiometer (MODIS) data to assess the influence of snowmelt timing and elevation on five phenology metrics (green up, maximum greenness, senescence, dormancy, and growing season length) within Crater Lake National Park, Oregon, USA from 2001 to 2012. Earlier annual mean snowmelt timing was significantly correlated with earlier onset of green up at the landscape scale. Snowmelt timing and elevation have significant explanatory power for phenology, though with high variability. Elevation has a moderate control on early season indicators such as snowmelt timing and green up and less on late-season variables such as senescence and growing season length. PCA results show that early season indicators and late season indicators vary independently. These results have important implications for ecosystem dynamics, management, and conservation, particularly of species such as whitebark pine ( Pinus albicaulis) in alpine and subalpine areas.
Niu, Lihua; Zhang, Xue; Li, Yi; Wang, Peifang; Zhang, Wenlong; Wang, Chao; Wang, Qing
2017-07-01
Due to the important roles of archaea in wastewater treatment processes, archaeal communities have been studied extensively in various anaerobic reactors, but the knowledge of archaeal communities in full-scale activated sludge wastewater treatment plants (WWTPs) remains quite poor. In this study, 454-pyrosequencing was for the first time employed to investigate archaeal communities from 20 full-scale activated sludge WWTPs distributed at a 3,660-meter elevational scale in China. Results showed that archaeal communities from WWTPs were dominated by Methanosarcinales (84.6%). A core archaeal population (94.5%) composed of Methanosaeta, Methanosarcina, Methanogenium and Methanobrevibacter was shared among WWTPs. The elevational pattern of archaeal communities was observed in WWTPs, with an elevational threshold associated with archaeal community richness and structures at approximately 1,500 meters above sea level (masl). A declining trend in community richness with increasing elevation was observed at higher elevations, whereas no trend was presented at lower elevations. Spearman correlation analysis indicated that the archaeal community richness at higher elevations was associated with more environmental variables than that at lower elevations. Redundancy analysis indicated that wastewater variables were the dominant contributors to the variation of community structures at higher elevations, followed by operational variables and elevation.
The Research on Elevation Change of Antarctic Ice Sheet Based on CRYOSAT-2 Alimeter
NASA Astrophysics Data System (ADS)
Sun, Q.; Wan, J.; Liu, S.; Li, Y.
2018-04-01
In this paper, the Cryosat-2 altimeter data distributed by the ESA, and these data are processed to extract the information of the elevation change of the Antarctic ice sheet from 2010 to 2017. Firstly, the main pretreatment preprocessing for Cryosat-2 altimetry data is crossover adjustment and elimination of rough difference. Then the grid DEM of the Antarctic ice sheet was constructed by using the kriging interpolation method,and analyzed the spatial characteristic time characteristics of the Antarctic ice sheet. The latitude-weighted elevation can be obtained by using the elevation data of each cycle, and then the general trend of the Antarctic ice sheet elevation variation can be seen roughly.
Soluble tumor necrosis factor receptor-I in preterm infants with chorioamnionitis.
Sato, Miho; Nishimaki, Shigeru; An, Hiromi; Shima, Yoshio; Naruto, Takuya; Sugai, Toshiyuki; Iwasaki, Shiho; Seki, Kazuo; Imagawa, Tomoyuki; Mori, Masaaki; Yokota, Shumpei
2009-04-01
The aim of our study was (i) to determine whether chorioamnionitis (CAM) is associated with an elevated soluble tumor necrosis factor receptor I (sTNFR-I) level and (ii) to examine the time course of the concentration of sTNFR-I in preterm infants after birth. We measured sTNFR-I levels in the cord blood of 112 preterm infants (gestational age < or =34 weeks), and those in peripheral blood of 30 preterm infants on days 7, 14, 21 and 28. The median value for the sTNFR-I was significantly elevated in 33 infants with CAM at stage 3 (4618 pg/mL) compared with the 52 infants without CAM (2866 pg/mL), or the 13 infants with CAM at stage 1 (3638 pg/mL) and the 14 infants at stage 2 (3242 pg/mL). The severity of CAM is an independent factor for the elevation of cord blood sTNFR-I. The sTNFR-I level on day 0 was significantly higher in eight infants with CAM at stage 3 than in the 22 infants without CAM or with CAM at stage 1 and 2; however there were no significant differences on days 7, 14, 21 and 28. The serum level of sTNFR-I showed a significant gradual decline with time. We suggest that there is an association between elevated sTNFR-I levels in cord blood and maternal CAM, and this elevation may reflect the fetal inflammation. However the elevation of sTNFR-I could not persist postnatally for a long time.
Lee, Terrie M.; Fouad, Geoffrey G.
2014-01-01
In Florida’s karst terrain, where groundwater and surface waters interact, a mapping time series of the potentiometric surface in the Upper Floridan aquifer offers a versatile metric for assessing the hydrologic condition of both the aquifer and overlying streams and wetlands. Long-term groundwater monitoring data were used to generate a monthly time series of potentiometric surfaces in the Upper Floridan aquifer over a 573-square-mile area of west-central Florida between January 2000 and December 2009. Recorded groundwater elevations were collated for 260 groundwater monitoring wells in the Northern Tampa Bay area, and a continuous time series of daily observations was created for 197 of the wells by estimating missing daily values through regression relations with other monitoring wells. Kriging was used to interpolate the monthly average potentiometric-surface elevation in the Upper Floridan aquifer over a decade. The mapping time series gives spatial and temporal coherence to groundwater monitoring data collected continuously over the decade by three different organizations, but at various frequencies. Further, the mapping time series describes the potentiometric surface beneath parts of six regionally important stream watersheds and 11 municipal well fields that collectively withdraw about 90 million gallons per day from the Upper Floridan aquifer. Monthly semivariogram models were developed using monthly average groundwater levels at wells. Kriging was used to interpolate the monthly average potentiometric-surface elevations and to quantify the uncertainty in the interpolated elevations. Drawdown of the potentiometric surface within well fields was likely the cause of a characteristic decrease and then increase in the observed semivariance with increasing lag distance. This characteristic made use of the hole effect model appropriate for describing the monthly semivariograms and the interpolated surfaces. Spatial variance reflected in the monthly semivariograms decreased markedly between 2002 and 2003, timing that coincided with decreases in well-field pumping. Cross-validation results suggest that the kriging interpolation may smooth over the drawdown of the potentiometric surface near production wells. The groundwater monitoring network of 197 wells yielded an average kriging error in the potentiometric-surface elevations of 2 feet or less over approximately 70 percent of the map area. Additional data collection within the existing monitoring network of 260 wells and near selected well fields could reduce the error in individual months. Reducing the kriging error in other areas would require adding new monitoring wells. Potentiometric-surface elevations fluctuated by as much as 30 feet over the study period, and the spatially averaged elevation for the entire surface rose by about 2 feet over the decade. Monthly potentiometric-surface elevations describe the lateral groundwater flow patterns in the aquifer and are usable at a variety of spatial scales to describe vertical groundwater recharge and discharge conditions for overlying surface-water features.
Quan, Erik; Mahmood, Rizwan; Naik, Amar; Sargon, Peter; Shastri, Nikhil; Venu, Mukund; Parada, Jorge P; Gupta, Neil
2018-05-21
There have been reported outbreaks of carbapenem-resistant Enterobacteriaceae infections linked to endoscopes with elevator mechanisms. Adenosine triphosphate (ATP) testing has been used as a marker for bioburden and monitoring manual cleaning for flexible endoscopes with and without an elevator mechanism. The objective of this study was to determine whether routine ATP testing could identify areas of improvement in cleaning of endoscopes with an elevator mechanism. ATP testing after manual cleaning of TJF-Q180V duodenoscopes and GF-UCT180 linear echoendoscopes (Olympus America Inc, Center Valley, PA) was implemented. Samples were tested from the distal end, the elevator mechanism, and water flushed through the lumen of the biopsy channel. Data were recorded and compared by time point, test point, and reprocessing technician. Overall failure rate was 6.99% (295 out of 4,219). The highest percentage of failed ATP tests (17.05%) was reported in the first quarter of routine testing, with an overall decrease in rates over time. The elevator mechanism and working channel lumen had higher failure rates than the distal end. Quality of manual cleaning between reprocessing technicians showed variation. ATP testing is effective in identifying residual organic material and improving quality of manual cleaning of endoscopes with an elevator mechanism. Cleaning efficacy is influenced by reprocessing technicians and location tested on the endoscope. Close attention to the working channel and elevator mechanism during manual cleaning is warranted. Copyright © 2018 Association for Professionals in Infection Control and Epidemiology, Inc. Published by Elsevier Inc. All rights reserved.
Szucs, Kimberly A; Borstad, John D
2013-12-01
The aim of this study was to provide a description of gender differences of the normal muscle activation patterns of the four subdivisions of the trapezius (clavicular, descending, transverse, ascending) during arm elevation. Surface EMG was collected from these four subdivisions from twenty-two healthy subjects (12 females, 10 males) during arm elevation in the scapular plane. Percent activation (RMS) of each subdivision was compared between genders across arm angles and elevation phase and onset time of each subdivision was compared between genders. Females demonstrated significantly higher % activation levels for each subdivision (p<.05), except transverse trapezius (p=.36). A statistically significant difference for onset time was observed between gender for the descending trapezius, with a slower onset time for females (p<.05). Findings from this study support the theory that subdivisions within descending trapezius are preferentially activated and demonstrate that gender differences are present within the fourth subdivision of trapezius. As subjects were without shoulder pathology, the observed gender differences may be explained by normal motor control variations. However, as coordinated activation of trapezius is required for normal shoulder motion, it is recommended to include all four subdivisions of trapezius and address gender differences in future studies. Copyright © 2013 Elsevier B.V. All rights reserved.
Background-Source Cosmic-Photon Elevation Scaling and Cosmic-Neutron/Photon Date Scaling in MCNP6
Tutt, James Robert; Anderson, Casey Alan; McKinney, Gregg Walter
2017-10-26
Here, cosmic neutron and photon fluxes are known to scale exponentially with elevation. Consequently, cosmic neutron elevation scaling was implemented for use with the background-source option shortly after its introduction into MCNP6, whereby the neutron flux weight factor was adjusted by the elevation scaling factor when the user-specified elevation differed from the selected background.dat grid-point elevation. At the same time, an elevation scaling factor was suggested for the cosmic photon flux, however, cosmic photon elevation scaling is complicated by the fact that the photon background consists of two components: cosmic and terrestrial. Previous versions of the background.dat file did notmore » provide any way to separate these components. With Rel. 4 of this file in 2015, two new columns were added that provide the energy grid and differential cosmic photon flux separately from the total photon flux. Here we show that the cosmic photon flux component can now be scaled independently and combined with the terrestrial component to form the total photon flux at a user-specified elevation in MCNP6.« less
Background-Source Cosmic-Photon Elevation Scaling and Cosmic-Neutron/Photon Date Scaling in MCNP6
DOE Office of Scientific and Technical Information (OSTI.GOV)
Tutt, James Robert; Anderson, Casey Alan; McKinney, Gregg Walter
Here, cosmic neutron and photon fluxes are known to scale exponentially with elevation. Consequently, cosmic neutron elevation scaling was implemented for use with the background-source option shortly after its introduction into MCNP6, whereby the neutron flux weight factor was adjusted by the elevation scaling factor when the user-specified elevation differed from the selected background.dat grid-point elevation. At the same time, an elevation scaling factor was suggested for the cosmic photon flux, however, cosmic photon elevation scaling is complicated by the fact that the photon background consists of two components: cosmic and terrestrial. Previous versions of the background.dat file did notmore » provide any way to separate these components. With Rel. 4 of this file in 2015, two new columns were added that provide the energy grid and differential cosmic photon flux separately from the total photon flux. Here we show that the cosmic photon flux component can now be scaled independently and combined with the terrestrial component to form the total photon flux at a user-specified elevation in MCNP6.« less
The application of geostationary propagation models to non-geostationary propagation measurements
NASA Astrophysics Data System (ADS)
Haddock, Paul Christopher
Atmospheric attenuation becomes evident above 10 GHz due to the absorption of microwave energy from the molecular motion of the atmospheric constituents. Atmospheric effects on satellite communications systems operating at frequencies greater than 10 GHz become more pronounced. Most geostationary (GEO) climate models, which predict the fading statistics for earth-space telecommunications, have satellite elevation angle as one of the input parameters. There has been an interest in the industry to apply the propagation models developed for the GEO satellites to the non-geostationary (NGO) satellite case. With the NGO satellites, the elevation angle to the satellite is time-variable, and as a result the earth-space propagation medium is time varying. We can calculate the expected probability that a satellite, in a given orbit, will be found at a given elevation angle as a percentage of the year based on the satellite orbital elements, the minimum elevation angle allowed in the constellation operation plan, and the constellation configuration. From this calculation, we can develop an empirical fit to a given probability density function (PDF) to account for the distribution of elevation angles. This PDF serves as a weighting function for the elevation input into the GEO climate model to produce the overall fading statistics for the NGO case. In this research, a Ka-band total power radiometer was developed to measure the down-dwelling incoherent radiant electromagnetic energy from the atmosphere. This whole sky sampling radiometer collected 1 year of radiometric measurements. These observations occurred at varying elevation and azimuthal angles, in close proximity to a weak water vapor absorption line. By referencing the output power of the radiometer to known radiometric emissions and by performing frequent internal calibrations, the developed radiometer provided long term highly accurate and stable low-level derived attenuation measurements. By correlating the 1 year of atmospheric measurements to the modified GEO climate model, the hypothesis is tested. That by application of the proper elevation weighting factors, the GEO model is applicable to the NGO case, where the time-varying angle changes are occurring on a short-time period. Finally, we look at the joint statistics of multiple link failures. Using the 1 year of observed attenuations for multiple sky sections, we show that for a given sky section what the probability is that its attenuation level will be equaled or exceeded for each of the remaining sky sections.
NASA Astrophysics Data System (ADS)
Zhang, Haichong K.; Fang, Ting Yun; Finocchi, Rodolfo; Boctor, Emad M.
2017-03-01
Three dimensional (3D) ultrasound imaging is becoming a standard mode for medical ultrasound diagnoses. Conventional 3D ultrasound imaging is mostly scanned either by using a two dimensional matrix array or by motorizing a one dimensional array in the elevation direction. However, the former system is not widely assessable due to its cost, and the latter one has limited resolution and field-of-view in the elevation axis. Here, we propose a 3D ultrasound imaging system based on the synthetic tracked aperture approach, in which a robotic arm is used to provide accurate tracking and motion. While the ultrasound probe is moved by a robotic arm, each probe position is tracked and can be used to reconstruct a wider field-of-view as there are no physical barriers that restrict the elevational scanning. At the same time, synthetic aperture beamforming provides a better resolution in the elevation axis. To synthesize the elevational information, the single focal point is regarded as the virtual element, and forward and backward delay-andsum are applied to the radio-frequency (RF) data collected through the volume. The concept is experimentally validated using a general ultrasound phantom, and the elevational resolution improvement of 2.54 and 2.13 times was measured at the target depths of 20 mm and 110 mm, respectively.
Technology Development and Demonstration Concepts for the Space Elevator
NASA Technical Reports Server (NTRS)
Smitherman, David V., Jr.
2004-01-01
During the 1990s several discoveries and advances in the development of carbon nano-tube (CNT) materials indicated that material strengths many times greater than common high-strength composite materials might be possible. Progress in the development of this material led to renewed interest in the space elevator concept for construction of a tether structure from the surface of the Earth through a geostationary orbit (GEO) and thus creating a new approach to Earth-to-orbit transportation infrastructures. To investigate this possibility the author, in 1999, managed for NASA a space elevator work:hop at the Marshall Space Flight Center to explore the potential feasibility of space elevators in the 21 century, and to identify the critical technologies and demonstration missions needed to make development of space elevators feasible. Since that time, a NASA Institute for Advanced Concepts (NIAC) funded study of the Space Elevator proposed a concept for a simpler first space elevator system using more near-term technologies. This paper will review some of the latest ideas for space elevator development, the critical technologies required, and some of the ideas proposed for demonstrating the feasibility for full-scale development of an Earth to GEO space elevator. Critical technologies include CNT composite materials, wireless power transmission, orbital object avoidance, and large-scale tether deployment and control systems. Numerous paths for technology demonstrations have been proposed utilizing ground experiments, air structures. LEO missions, the space shuttle, the international Space Station, GEO demonstration missions, demonstrations at the lunar L1 or L2 points, and other locations. In conclusion, this paper finds that the most critical technologies for an Earth to GEO space elevator include CNT composite materials development and object avoidance technologies; that lack of successful development of these technologies need not preclude continued development of space elevator systems in general; and that the critical technologies required for the Earth to GEO space elevator are not required for similar systems at the Moon, Mars, Europa, or for orbital tether systems at GEO, Luna, and other locations.
Fischer, Michael J.; Kimmel, Paul L.; Greene, Tom; Gassman, Jennifer J.; Wang, Xuelei; Brooks, Deborah H.; Charleston, Jeanne; Dowie, Donna; Thornley-Brown, Denyse; Cooper, Lisa A.; Bruce, Marino A.; Kusek, John W.; Norris, Keith C.; Lash, James P.
2011-01-01
This study was designed to examine the impact of elevated depressive affect on health outcomes among participants with hypertensive chronic kidney disease in the African-American Study of Kidney Disease and Hypertension (AASK) Cohort Study. Elevated depressive affect was defined by Beck Depression Inventory II (BDI-II) thresholds of 11 or more, above 14, and by 5-Unit increments in the score. Cox regression analyses were used to relate cardiovascular death/hospitalization, doubling of serum creatinine/end-stage renal disease, overall hospitalization, and all-cause death to depressive affect evaluated at baseline, the most recent annual visit (time-varying), or average from baseline to the most recent visit (cumulative). Among 628 participants at baseline, 42% had BDI-II scores of 11 or more and 26% had a score above 14. During a 5-year follow-up, the cumulative incidence of cardiovascular death/hospitalization was significantly greater for participants with baseline BDI-II scores of 11 or more compared with those with scores <11. The baseline, time-varying, and cumulative elevated depressive affect were each associated with a significant higher risk of cardiovascular death/hospitalization, especially with a time-varying BDI-II score over 14 (adjusted HR 1.63) but not with the other outcomes. Thus, elevated depressive affect is associated with unfavorable cardiovascular outcomes in African Americans with hypertensive chronic kidney disease. PMID:21633409
NASA Astrophysics Data System (ADS)
Huntington, K. W.; Wernicke, B. P.; Eiler, J. M.
2009-05-01
Topography is a first-order expression of the buoyancy of the lithosphere, and the timing and pattern of elevation change can place fundamental constraints on mantle flow and continental dynamics. We investigate the timing of Colorado Plateau uplift using clumped-isotope thermometry to independently constrain both the temperature and isotopic composition of ancient surface waters based on the 13C-18O bond enrichment in carbonates. Analyses of ancient lake sediments from the plateau interior and adjacent lowlands are compared to signals recorded by modern sediments collected over 3 km of elevation in the region. Comparison of modern and ancient samples deposited near sea level provides an opportunity to quantify the influence of climate on changes in temperature, and therefore more accurately assess the contribution from changes in elevation. Both modern and ancient (Miocene-Pliocene) carbonates record near-surface spring/summer lake water temperatures that vary strongly with elevation. Modern and ancient lake carbonate temperature lapse rates of -4.2±0.7°C/km and -4.1±0.6°C/km, respectively, suggest that little if any post-16 Ma change in elevation of the southern plateau is required to explain the data. Agreement of δ18O data for modern and ancient surface waters supports this interpretation. The zero-elevation intercept of the ancient trend is 7.7±2.0°C warmer than the modern trend, indicating significant cooling due to climate change since Late Miocene time. The temperature data are permissive of up to 450 m of uplift or 250 m of subsidence of the plateau interior since 6 Ma, but do not support km-scale changes. Combined with previous constraints, the data suggest that most uplift of the south-central plateau occurred during Late Cretaceous/earliest Tertiary time, favoring uplift mechanisms such as crustal thickening by channel flow, hydration of the mantle lithosphere due to volatile flux from the Laramide flat slab, or dynamic topography associated with slab foundering. The data do not support explanations that ascribe most uplift to ca. 40-0 Ma disposal of the Farallon or North American mantle lithosphere.
NORAD LOOK ANGLES AND PIO SATELLITE PACKAGE
NASA Technical Reports Server (NTRS)
ANONYMOUS
1994-01-01
This program package consists of two programs. First is the NORAD Look Angles Program, which computes satellite look angles (azimuth, elevation, and range) as well as the subsatellite points (latitude, longitude, and height). The second program in this package is the PIO Satellite Program, which computes sighting directions, visibility times, and the maximum elevation angle attained during each pass of an earth-orbiting satellite. Computations take into consideration the observing location and the effect of the earth's shadow on the satellite visibility. Input consists of a magnetic tape prepared by the NORAD Look Angles Program and punched cards containing reference Julian date, right ascension, declination, mean sidereal time at zero hours universal time of the reference date, and daily changes of these quantities. Output consists of a tabulated listing of the satellite's rise and set times, direction, and the maximum elevation angle visible from each observing location. This program has been implemented on the GE 635. The program Assembler code can easily be replaced by FORTRAN statements.
NASA Astrophysics Data System (ADS)
Khandelwal, A.; Karpatne, A.; Kumar, V.
2017-12-01
In this paper, we present novel methods for producing surface water maps at 30 meter spatial resolution at a daily temporal resolution. These new methods will make use of the MODIS spectral data from Terra (available daily since 2000) to produce daily maps at 250 meter and 500 meter resolution, and then refine them using the relative elevation ordering of pixels at 30 meter resolution. The key component of these methods is the use of elevation structure (relative elevation ordering) of a water body. Elevation structure is not explicitly available at desired resolution for most water bodies in the world and hence it will be estimated using our previous work that uses the history of imperfect labels. In this paper, we will present a new technique that uses elevation structure (unlike existing pixel based methods) to enforce temporal consistency in surface water extents (lake area on nearby dates is likely to be very similar). This will greatly improve the quality of the MODIS scale land/water labels since daily MODIS data can have a large amount of missing (or poor quality) data due to clouds and other factors. The quality of these maps will be further improved using elevation based resolution refinement approach that will make use of elevation structure estimated at Landsat scale. With the assumption that elevation structure does not change over time, it provides a very effective way to transfer information between datasets even when they are not observed concurrently. In this work, we will derive elevation structure at Landsat scale from monthly water extent maps spanning 1984-2015, publicly available through a joint effort of Google Earth Engine and the European Commission's Joint Research Centre (JRC). This elevation structure will then be used to refine spatial resolution of Modis scale maps from 2000 onwards. We will present the analysis of these methods on a large and diverse set of water bodies across the world.
SRTM Data Release for Africa, Colored Height
2004-06-17
Elevation data at the highest possible resolution from NASA SRTM mission in February 2000 are being released for the first time for most of the African continent. This color shaded relief image shows the extent of SRTM digital elevation data for Africa.
Casteel, Clare L; O'Neill, Bridget F; Zavala, Jorge A; Bilgin, Damla D; Berenbaum, May R; Delucia, Evan H
2008-04-01
The accumulation of CO2 and O3 in the troposphere alters phytochemistry which in turn influences the interactions between plants and insects. Using microarray analysis of field-grown soybean (Glycine max), we found that the number of transcripts in the leaves affected by herbivory by Japanese beetles (Popillia japonica) was greater when plants were grown under elevated CO2, elevated O3 and the combination of elevated CO2 plus elevated O3 than when grown in ambient atmosphere. The effect of herbivory on transcription diminished strongly with time (<1% of genes were affected by herbivory after 3 weeks), and elevated CO2 interacted more strongly with herbivory than elevated O3. The majority of transcripts affected by elevated O3 were related to antioxidant metabolism. Constitutive levels and the induction by herbivory of key transcripts associated with defence and hormone signalling were down-regulated under elevated CO2; 1-aminocyclopropane-1-carboxylate (ACC) synthase, lipoxygenase (LOX), allene oxide synthase (AOS), allene oxide cyclase (AOC), chalcone synthase (CHS), polyphenol oxidase (PPO) and cysteine protease inhibitor (CystPI) were lower in abundance compared with levels under ambient conditions. By suppressing the ability to mount an effective defence, elevated CO2 may decrease resistance of soybean to herbivory.
Divergent phenological response to hydroclimate variability in forested mountain watersheds.
Hwang, Taehee; Band, Lawrence E; Miniat, Chelcy F; Song, Conghe; Bolstad, Paul V; Vose, James M; Love, Jason P
2014-08-01
Mountain watersheds are primary sources of freshwater, carbon sequestration, and other ecosystem services. There is significant interest in the effects of climate change and variability on these processes over short to long time scales. Much of the impact of hydroclimate variability in forest ecosystems is manifested in vegetation dynamics in space and time. In steep terrain, leaf phenology responds to topoclimate in complex ways, and can produce specific and measurable shifts in landscape forest patterns. The onset of spring is usually delayed at a specific rate with increasing elevation (often called Hopkins' Law; Hopkins, 1918), reflecting the dominant controls of temperature on greenup timing. Contrary with greenup, leaf senescence shows inconsistent trends along elevation gradients. Here, we present mechanisms and an explanation for this variability and its significance for ecosystem patterns and services in response to climate. We use moderate-resolution imaging spectro-radiometer (MODIS) Normalized Difference Vegetation Index (NDVI) data to derive landscape-induced phenological patterns over topoclimate gradients in a humid temperate broadleaf forest in southern Appalachians. These phenological patterns are validated with different sets of field observations. Our data demonstrate that divergent behavior of leaf senescence with elevation is closely related to late growing season hydroclimate variability in temperature and water balance patterns. Specifically, a drier late growing season is associated with earlier leaf senescence at low elevation than at middle elevation. The effect of drought stress on vegetation senescence timing also leads to tighter coupling between growing season length and ecosystem water use estimated from observed precipitation and runoff generation. This study indicates increased late growing season drought may be leading to divergent ecosystem response between high and low elevation forests. Landscape-induced phenological patterns are easily observed over wide areas and may be used as a unique diagnostic for sources of ecosystem vulnerability and sensitivity to hydroclimate change. © 2014 John Wiley & Sons Ltd.
Robert R. Ziemer
1963-01-01
Abstract - The quantity of summer soil moisture loss from logged forest openings was related to the length of time since the creation of the opening in a study made in the subalpine forest zone of the Sierra Nevada west-side near the Central Sierra Snow Laboratory, California, within the elevational range of 6,000 to 7,000 feet. Soil moisture depletion was measured in...
Fatigue crack growth at elevated temperature 316 stainless steel and H-13 steel
NASA Technical Reports Server (NTRS)
Chen, W. C.; Liu, H. W.
1976-01-01
Crack growths were measured at elevated temperatures under four types of loading: pp, pc, cp, and cc. In H-13 steel, all these four types of loading gave nearly the same crack growth rates, and the length of hold time had negligible effects. In AISI 316 stainless steel, the hold time effects on crack growth rate were negligible if the loading was tension-tension type; however, these effects were significant in reversed bending load, and the crack growth rates under these four types of loading varied considerably. Both tensile and compressive hold times caused increased crack growth rate, but the compressive hold period was more deleterious than the tensile one. Metallographic examination showed that all the crack paths under different types of loading were largely transgranular for both CTS tension-tension specimens and SEN reversed cantilever bending specimens. In addition, an electric potential technique was used to monitor crack growth at elevated temperature.
Use of piezosurgery during maxillary sinus elevation: clinical results of 40 consecutive cases.
Cassetta, Michele; Ricci, Laura; Iezzi, Giovanna; Calasso, Sabrina; Piattelli, Adriano; Perrotti, Vittoria
2012-12-01
The aim of this study was to evaluate the performance of piezoelectric devices during sinus elevation to determine the percentage of sinus membrane perforation and the time required to perform the antrostomy and elevation of the membrane. A total of 35 patients and 40 grafted sinuses were included. The parameters recorded were bony window length and height, bone thickness, osteotomy area, operative time, and number of perforations. Seven (17.5%) membrane perforations were observed, which were repaired with resorbable membranes. The mean length, height, and thickness of the osteotomy were 13.8 ± 2.9 mm, 6.9 ± 1.4 mm, and 1.4 ± 0.4 mm, respectively. The mean osteotomy area was 96.8 ± 32.2 mm(2), and the mean operative time was 10.3 ± 2.1 minutes. This study demonstrated that a piezoelectric device could be an attractive alternative for successful sinus augmentation.
8. Elevation view of midsection of west wall of South ...
8. Elevation view of midsection of west wall of South Section. This photo makes an extended elevation panorama with photos WA-116-E-7 and WA-116-E-9. Note that Crane No. 42 also appears in photo WA-116-E-7. This is because the crane moved in the time that the photographer moved the camera. - Puget Sound Naval Shipyard, Drydock No. 3, Farragut Avenue, Bremerton, Kitsap County, WA
López-Crespo, G A; Flores, P; Sánchez-Santed, F; Sánchez-Amate, M C
2009-11-01
Chlorpyrifos (CPF) is a broad spectrum organophosphate (OP) pesticide widely used in agriculture, industry and household. Several animal studies indicate emotional disturbances after CPF exposure, although the results are sometimes puzzling. Thus, both anxiolytic and anxiogenic effects of CPF have been reported in different animal models of anxiety [Sánchez-Amate MC, Flores P, Sánchez-Santed F. Effects of chlorpyrifos in the plus-maze model of anxiety. Behav Pharmacol 2001;12:285-92; Sánchez-Amate MC, Dávila E, Cañadas F, Flores P, Sánchez-Santed F. Chlorpyrifos shares stimulus properties with pentilenetetrazol as evaluated by and operant drug discrimination task. Neurotoxicology 2002;23:795-803; López-Crespo G, Carvajal F, Flores P, Sánchez-Santed F, Sánchez-Amate MC. Time-course of biochemical and behavioural effects of a single high dose of chlorpyrifos. Neurotoxicology 2007;28:541-7]. On the other hand, other behavioural effects of CPF are time-dependent [López-Crespo G, Carvajal F, Flores P, Sánchez-Santed F, Sánchez-Amate MC. Time-course of biochemical and behavioural effects of a single high dose of chlorpyrifos. Neurotoxicology 2007;28:541-7], raising the question that the effects of CPF could be task and post-administration time dependent. To test this hypothesis, three groups of rats were treated with a single high dose of CPF (250 mg/kg); one of the groups was tested on day 5 on the elevated plus-maze, to complete our previous study on day 2 [Sánchez-Amate MC, Flores P, Sánchez-Santed F. Effects of chlorpyrifos in the plus-maze model of anxiety. Behav Pharmacol 2001;12:285-92]. The remaining groups were tested on the elevated T-maze on days 2 and 5. CPF produced an increased open arm activity on the elevated plus-maze on day 5, an increased escape latency on the elevated T-maze on day 2 and an impaired inhibitory avoidance on day 5. Data are discussed taking together all studies carried out in our laboratory, confirming that CPF effects on emotional behaviour are dependent on both task contingencies and post-administration time.
Curiosity Rover Martian Mission, Exaggerated Cross Section
2016-12-13
This graphic depicts aspects of the driving distance, elevation, geological units and time intervals of NASA's Curiosity Mars rover mission, as of late 2016. The vertical dimension is exaggerated 14-fold compared with the horizontal dimension, for presentation-screen proportions. As of early December 2016, Curiosity had driven 9.3 miles (15 kilometers) since its August 2012 landing on the floor of Gale Crater near the base of Mount Sharp. It had climbed 541 feet (165 meters) in elevation. Elevation values shown on the vertical scale of this chart denote meters below an established zero-elevation level on Mars, which lacks a planetary "sea level." Because Curiosity is below the zero elevation, the numbers are negative. http://photojournal.jpl.nasa.gov/catalog/PIA21145
Trigas, Panayiotis; Panitsa, Maria; Tsiftsis, Spyros
2013-01-01
Understanding diversity patterns along environmental gradients and their underlying mechanisms is a major topic in current biodiversity research. In this study, we investigate for the first time elevational patterns of vascular plant species richness and endemism on a long-isolated continental island (Crete) that has experienced extensive post-isolation mountain uplift. We used all available data on distribution and elevational ranges of the Cretan plants to interpolate their presence between minimum and maximum elevations in 100-m elevational intervals, along the entire elevational gradient of Crete (0–2400 m). We evaluate the influence of elevation, area, mid-domain effect, elevational Rapoport effect and the post-isolation mountain uplift on plant species richness and endemism elevational patterns. Furthermore, we test the influence of the island condition and the post-isolation mountain uplift to the elevational range sizes of the Cretan plants, using the Peloponnese as a continental control area. Total species richness monotonically decreases with increasing elevation, while endemic species richness has a unimodal response to elevation showing a peak at mid-elevation intervals. Area alone explains a significant amount of variation in species richness along the elevational gradient. Mid-domain effect is not the underlying mechanism of the elevational gradient of plant species richness in Crete, and Rapoport's rule only partly explains the observed patterns. Our results are largely congruent with the post-isolation uplift of the Cretan mountains and their colonization mainly by the available lowland vascular plant species, as high-elevation specialists are almost lacking from the Cretan flora. The increase in the proportion of Cretan endemics with increasing elevation can only be regarded as a result of diversification processes towards Cretan mountains (especially mid-elevation areas), supported by elevation-driven ecological isolation. Cretan plants have experienced elevational range expansion compared to the continental control area, as a result of ecological release triggered by increased species impoverishment with increasing elevation. PMID:23555031
Gupta, Aakriti; Barrabes, Jose A; Strait, Kelly; Bueno, Hector; Porta-Sánchez, Andreu; Acosta-Vélez, J Gabriel; Lidón, Rosa-Maria; Spatz, Erica; Geda, Mary; Dreyer, Rachel P; Lorenze, Nancy; Lichtman, Judith; D'Onofrio, Gail; Krumholz, Harlan M
2018-03-07
Young women with ST-segment-elevation myocardial infarction experience reperfusion delays more frequently than men. Our aim was to determine the electrocardiographic correlates of delay in reperfusion in young patients with ST-segment-elevation myocardial infarction. We examined sex differences in initial electrocardiographic characteristics among 1359 patients with ST-segment-elevation myocardial infarction in a prospective, observational, cohort study (2008-2012) of 3501 patients with acute myocardial infarction, 18 to 55 years of age, as part of the VIRGO (Variation in Recovery: Role of Gender on Outcomes of Young AMI Patients) study at 103 US and 24 Spanish hospitals enrolling in a 2:1 ratio for women/men. We created a multivariable logistic regression model to assess the relationship between reperfusion delay (door-to-balloon time >90 or >120 minutes for transfer or door-to-needle time >30 minutes) and electrocardiographic characteristics, adjusting for sex, sociodemographic characteristics, and clinical characteristics at presentation. In our study (834 women and 525 men), women were more likely to exceed reperfusion time guidelines than men (42.4% versus 31.5%; P <0.01). In multivariable analyses, female sex persisted as an important factor in exceeding reperfusion guidelines after adjusting for electrocardiographic characteristics (odds ratio, 1.57; 95% CI, 1.15-2.15). Positive voltage criteria for left ventricular hypertrophy and absence of a prehospital ECG were positive predictors of reperfusion delay; and ST elevation in lateral leads was an inverse predictor of reperfusion delay. Sex disparities in timeliness to reperfusion in young patients with ST-segment-elevation myocardial infarction persisted, despite adjusting for initial electrocardiographic characteristics. Left ventricular hypertrophy by voltage criteria and absence of prehospital ECG are strongly positively correlated and ST elevation in lateral leads is negatively correlated with reperfusion delay. © 2018 The Authors. Published on behalf of the American Heart Association, Inc., by Wiley.
TRMM-3B43 Bias Correction over the High Elevations of the Contiguous United States
NASA Astrophysics Data System (ADS)
Hashemi, H.; Nordin, K. M.; Lakshmi, V.; Knight, R. J.
2016-12-01
Precipitation can be quantified using a rain gauge network, or a remotely sensed precipitation product. Ultimately, the choice of dataset depends on the particular application, the catchment size, climate and the time period of study. In a region with a long record and a dense rain gauge network, the elevation-modified ground-based precipitation product, PRISM, has been found to work well. However, in poorly gauged regions the use of remotely sensed precipitation products is an absolute necessity. The Tropical Rainfall Measuring Mission (TRMM) has provided valuable precipitation datasets for hydrometeorological studies over the past two decades (1998-2015). One concern regarding the usage of TRMM data is the accuracy of the precipitation estimates, when compared to those obtained using PRISM. The reason for this concern is that TRMM and PRISM do not always agree and, typically, TRMM underestimates PRISM over the mountainous regions of the United States. In this study, we develop a correction function to improve the accuracy of the TRMM monthly product (TRMM-3B43) by estimating and removing the bias in the satellite data using the ground-based precipitation product, PRISM. We observe a strong relationship between the bias and land surface elevation; TRMM-3B43 tends to underestimate the PRISM product at altitudes greater than 1500 m above mean sea level (m.amsl) in the contiguous United States. A relationship is developed between TRMM-PRISM bias and elevation. The correction function is used to adjust the TRMM monthly precipitation using PRISM and elevation data. The model is calibrated using 25% of the available time period and the remaining 75% of the time period is used for validation. The corrected TRMM-3B43 product is verified for the high elevations over the contiguous United States and two local regions in the mountainous areas of the western United States. The results show a significant improvement in the accuracy of the TRMM product in the high elevations of the contiguous United States.
Casciano, Julian; Krishnan, Jerry; Dotiwala, Zenobia; Li, Chenghui; Sun, Shawn X
2017-01-01
The European Respiratory Society and American Thoracic Society (ERS/ATS) published guidelines in 2014 for the evaluation and treatment of asthma. These guidelines draw attention to management of patients with asthma that remains uncontrolled despite therapy. One phenotypic characteristic of therapy-resistant asthma is eosinophil elevation. It is important to better understand the burden of care gaps in this patient subgroup in order to support improved treatment strategies in the future. To quantify the economic burden of asthma patients with and without peripheral blood eosinophil elevation. A retrospective cohort study was conducted using data from patients aged 12 years or older with a diagnosis of asthma using electronic health records of over 2 million patients between 2004-2010. Patients with a diagnosis of chronic obstructive pulmonary disease, Churg Strauss syndrome/Wegener's granulomatosis, eosinophilia, cystic/pulmonary fibrosis, allergic bronchopulmonary aspergillosis, or lung cancer in the 12-month period before the date of asthma diagnosis were excluded. Patients with asthma were followed for 12 months after their initial asthma diagnosis to identify those with controlled versus uncontrolled asthma based on ERS/ATS criteria. Patients with at least 1 peripheral blood eosinophil test result of ≥ 400 cells/µL were classified as those with elevated eosinophils. Total annual paid-claim cost was compared by eosinophil levels within the controlled and uncontrolled asthma subgroups. Costs were adjusted to 2015 U.S. dollars. Patients were stratified by control level, and generalized linear modeling regressions were used to assess the magnitude of increase in cost of the elevated eosinophil group. A total of 2,701 patients were included in the study, of which 17% had uncontrolled asthma and 21% had elevated eosinophils. The mean total annual cost of patients with uncontrolled asthma was more than 2 times the cost of those with controlled asthma ($18,341 vs. $8,670, P < 0.001). Patients with uncontrolled asthma in the elevated eosinophil group had almost double the total cost ($28,644 vs. $14,188, P = 0.008) compared with those with blood eosinophil levels in a normal range. Similarly, patients classified as those with controlled asthma in the elevated eosinophil group had almost twice the average costs as those without elevated eosinophils ($14,754 vs. $7,203, P < 0.001). Uncontrolled asthma with elevated eosinophils had 4 times greater hospital admissions and over 4 times higher total costs than controlled asthma without elevated eosinophils. Among patients with uncontrolled asthma, patients with elevated eosinophils had a 53% increase in mean cost ($17,723 vs. $11,581, P < 0.001) compared with patients without elevated eosinophils. Among patients with controlled asthma, patients with elevated eosinophils had a 62% increase in mean cost ($8,897 vs. $5,486, P < 0.001) compared with patients without elevated eosinophils. Elevated peripheral blood eosinophil level is associated with higher cost irrespective of disease control status. This study was funded by Teva Pharmaceuticals. Dotiwala and Casciano report consulting and writing fees from Teva Pharmaceuticals for work on this study. Sun is an employee and stockholder of Teva Pharmaceuticals. Li reports consulting fees from eMAX Health. All authors contributed to study design. Dotiwala took the lead in data collection, along with the other authors, and data interpretation was performed primarily by Krishnan, Sun, and Li, along with Casciano and Dotiwala. The manuscript was written by Casciano, Dotiwala, and Li, along with Sun and Krishnan, and revised by Casciano, Dotiwala, Sun, and Li, with assistance from Krishnan.
NASA Technical Reports Server (NTRS)
Zwally, H. Jay; Jun, Li; Koblinsky, Chester J. (Technical Monitor)
2001-01-01
Observed seasonal and interannual variations in the surface elevation over the summit of the Greenland ice sheet are modeled using a new temperature-dependent formulation of firn-densification and observed accumulation variations. The observed elevation variations are derived from ERS (European Remote Sensing)-1 and ERS-2 radar altimeter data for the period between April 1992 and April 1999. A multivariate linear/sine function is fitted to an elevation time series constructed from elevation differences measured by radar altimetry at orbital crossovers. The amplitude of the seasonal elevation cycle is 0.25 m peak-to-peak, with a maximum in winter and a minimum in summer. Inter-annually, the elevation decreases to a minimum in 1995, followed by an increase to 1999, with an overall average increase of 4.2 cm a(exp -1) for 1992 to 1999. Our densification formulation uses an initial field-density profile, the AWS (automatic weather station) surface temperature record, and a temperature-dependent constitutive relation for the densification that is based on laboratory measurements of crystal growth rates. The rate constant and the activation energy commonly used in the Arrhenius-type constitutive relation for firn densification are also temperature dependent, giving a stronger temperature and seasonal amplitudes about 10 times greater than previous densification formulations. Summer temperatures are most important, because of the strong non-linear dependence on temperature. Much of firn densification and consequent surface lowering occurs within about three months of the summer season, followed by a surface build-up from snow accumulation until spring. Modeled interannual changes of the surface elevation, using the AWS measurements of surface temperature and accumulation and results of atmospheric modeling of precipitation variations, are in good agreement with the altimeter observations. In the model, the surface elevation decreases about 20 cm over the seven years due to more compaction driven by increasing summer temperatures. The minimum elevation in 1995 is driven mainly by a temporary accumulation decrease and secondarily by warmer temperatures. However, the overall elevation increase over the seven years is dominated by the accumulation increase in the later years.
The Phenylephrine Test Revisited.
Barsegian, Arpine; Botwinick, Adam; Reddy, Harsha S
To characterize the phenylephrine test in ptotic patients to help clinicians perform the test more efficiently. Adults with involutional ptosis (n = 24, 30 eyes) were assessed with digital photographs for response to topical 2.5% phenylephrine drop instillation. Patient characteristics (age, gender, iris color, dermatochalasis, brow ptosis, and baseline marginal reflex distance-1 [MRD-1] height) were recorded. From the photographs, change in (MRD-1), presence of conjunctival blanching, pupillary dilation, and Hering effect were recorded at specified time intervals, 1 minute to 1 hour after drop placement. Correlations between patient characteristics and measured outcomes were evaluated using analysis of variance, Pearson coefficient, or chi-square tests. The authors found that 73% of eyes had eyelid elevation with phenylephrine. Of these, 50% reached maximal eyelid elevation by 5 minutes, and 86% by 10 minutes after drop placement, but 14% did not reach maximal MRD-1 until 30 minutes. There is a negative correlation between the maximum MRD-1 and the baseline MRD-1 eyelid height (r = -0.5330, p < 0.01). There is no significant relationship between time to pupillary dilation with either time to max eyelid elevation or max eyelid elevation. No patient characteristic studied affected the likelihood of eyelid response to phenylephrine or presence of Hering effect. Although most ptotic eyelids demonstrate a response to 2.5% phenylephrine within 10 minutes, there is a subset of patients that respond much later. More ptotic eyelids had greater eyelid elevation with phenylephrine. Pupillary dilation and conjunctival blanching are neither predictive of nor temporally associated with eyelid height elevation. The authors did not identify any patient factors (e.g., dermatochalasis, brow ptosis) that can predict the likelihood of response to phenylephrine.
Payne, Jason; Woodward, Brenda K.; Storm, John B.
2009-01-01
The U.S. Geological Survey installed a network of pressure sensors at 65 sites along the Gulf Coast from Seadrift, Texas, northeast to Lake Charles, Louisiana, to record the timing, areal extent, and magnitude of inland storm surge and coastal flooding caused by Hurricane Ike in September 2008. A Global Positioning System was used to obtain elevations of reference marks near each sensor. A combination of real-time kinematic (RTK) and static Global Positioning System surveys were done to obtain elevations of reference marks. Leveling relative to reference marks was done to obtain elevations of sensor orifices above the reference marks. This report summarizes the Global Positioning System data collected and processed to obtain reference mark and storm-sensor-orifice elevations for 59 storm-surge sensors recovered from the original 65 installed as a necessary prelude to computation of storm-surge elevations. National Geodetic Survey benchmarks were used for RTK surveying. Where National Geodetic Survey benchmarks were not within 12 kilometers of a sensor site, static surveying was done. Additional control points for static surveying were in the form of newly established benchmarks or reestablished existing benchmarks. RTK surveying was used to obtain positions and elevations of reference marks for 29 sensor sites. Static surveying was used to obtain positions and elevations of reference marks for 34 sensor sites; four sites were surveyed using both methods. Multiple quality checks on the RTK-survey and static-survey data were applied. The results of all quality checks indicate that the desired elevation accuracy for the surveys of this report, less than 0.1-meter error, was achieved.
Liver dysfunction in patients with severe anorexia nervosa.
Rosen, Elissa; Sabel, Allison L; Brinton, John T; Catanach, Brittany; Gaudiani, Jennifer L; Mehler, Philip S
2016-02-01
Evaluation of liver dysfunction in patients with severe anorexia nervosa (AN) has typically been limited to small case series. We report an investigation into the admission characteristics and clinical outcomes associated with liver dysfunction in a large cohort of adults hospitalized for medical stabilization of severe AN. We retrospectively evaluated electronic medical records to quantify the cumulative incidence of elevated aspartate aminotransferase (AST) and alanine aminotransferase (ALT). We compared mean (±SD), frequencies (%), and median (IQR) values of clinical covariates of interest by incidence of liver enzyme elevation. The study included 181 adults, admitted for medical stabilization of AN, from October 1, 2008 to December 31, 2013. AST and ALT were mildly elevated in 27.6% of patients and severely elevated (more than three times the upper limit of normal) in 35.4% of patients. On admission, patients with severely elevated liver enzymes had a lower body mass index (BMI) (11.9 ± 1.8 kg/m(2) vs.13.3 ± 1.7 kg/m(2)), lower percentage ideal body weight (56.5% ± 7.7% vs. 63.5% ± 8.3%), and lower prealbumin (64% vs. 37%) compared with the rest of the cohort (p < 0.001). While hospitalized, patients with severely elevated liver enzymes more often developed hypoglycemia, hypophosphatemia, and experienced longer lengths of stay (p < 0.001). Elevated liver enzymes are common in our patient population with severe AN. Liver enzymes reached near normal values by the time of discharge. Severely elevated liver enzymes were associated with a lower BMI and the development of hypoglycemia. © 2015 Wiley Periodicals, Inc.
NASA Technical Reports Server (NTRS)
Webb, Charles E.; Zwally H. Jay; Abdalati, Waleed
2012-01-01
The Ice, Cloud and land Elevation Satellite (ICESat) mission was conceived, primarily, to quantify the spatial and temporal variations in the topography of the Greenland and Antarctic ice sheets. It carried on board the Geoscience Laser Altimeter System (GLAS), which measured the round-trip travel time of a laser pulse emitted from the satellite to the surface of the Earth and back. Each range derived from these measurements was combined with precise, concurrent orbit and pointing information to determine the location of the laser spot centroid on the Earth. By developing a time series of precise topographic maps for each ice sheet, changes in their surface elevations can be used to infer their mass balances.
NASA Astrophysics Data System (ADS)
Howat, I.; Noh, M. J.; Porter, C. C.; Smith, B. E.; Morin, P. J.
2017-12-01
We are creating the Reference Elevation Model of Antarctica (REMA), a continuous, high resolution (2-8 m), high precision (accuracy better than 1 m) reference surface for a wide range of glaciological and geodetic applications. REMA will be constructed from stereo-photogrammetric Digital Surface Models (DSM) extracted from pairs of submeter resolution DigitalGlobe satellite imagery and vertically registred to precise elevations from near-coincident airborne LiDAR, ground-based GPS surveys and Cryosat-2 radar altimetry. Both a seamless mosaic and individual, time-stamped DSM strips, collected primarily between 2012 and 2016, will be distributed to enable change measurement. These data will be used for mapping bed topography from ice thickness, measuring ice thickness changes, constraining ice flow and geodynamic models, mapping glacial geomorphology, terrain corrections and filtering of remote sensing observations, and many other science tasks. Is will also be critical for mapping ice traverse routes, landing sites and other field logistics planning. REMA will also provide a critical elevation benchmark for future satellite altimetry missions including ICESat-2. Here we report on REMA production progress, initial accuracy assessment and data availability.
Ikematsu, H; Nabeshima, A; Yamaga, S; Yamaji, K; Kakuda, K; Ueno, K; Hayashi, J; Shirai, T; Hara, H; Kashiwagi, S
1997-06-01
To investigate the clinical implication of peak body temperature, peripheral blood white blood cell (WBC) count, and serum C-reactive protein (CRP) level in febrile symptoms among geriatric hospitalized patients, they were analyzed in 968 febrile episodes obtained from 433 hospitalized patients in the referred hospital. Episodes of one day duration were most frequent (41.6%). WBC count was elevated over 8000/microliters in 475 episodes (49.1%) and CRP exceeded 1.0 mg/dl in 770 episodes (79.5%). Frequency of WBC elevation decreased and frequency of CRP elevation increased according to the time course. The mean value of CRP increased significantly according to the time course. The frequency of WBC count increase and CRP elevation and their averages correlated to the peak body temperature. The peak body temperature displayed the most striking correlation to the length of febrile episodes among three clinical indicators, peak body temperature, WBC count, and CRP level. These results indicate that the elevation of WBC count and/or CRP level is frequent in geriatric patients with febrile symptoms. Peak body temperature may serve as a clinical indicator of the severy of the febrile disease occurring in geriatric patients.
18 CFR 1304.412 - Definitions.
Code of Federal Regulations, 2011 CFR
2011-04-01
... CONSTRUCTION IN THE TENNESSEE RIVER SYSTEM AND REGULATION OF STRUCTURES AND OTHER ALTERATIONS Miscellaneous... targeted elevation to which TVA plans to fill each reservoir during its annual operating cycle. Applicants... summer pool elevation for the reservoir in question at the time the application is submitted. Land-based...
18 CFR 1304.412 - Definitions.
Code of Federal Regulations, 2010 CFR
2010-04-01
... CONSTRUCTION IN THE TENNESSEE RIVER SYSTEM AND REGULATION OF STRUCTURES AND OTHER ALTERATIONS Miscellaneous... targeted elevation to which TVA plans to fill each reservoir during its annual operating cycle. Applicants... summer pool elevation for the reservoir in question at the time the application is submitted. Land-based...
76 FR 20554 - Changes in Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-04-13
... management requirements. The community may at any time enact stricter requirements of its own or pursuant to... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA-2011-0002] Changes in Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS...
76 FR 8900 - Changes in Flood Elevation Determinations
Federal Register 2010, 2011, 2012, 2013, 2014
2011-02-16
... management requirements. The community may at any time enact stricter requirements of its own or pursuant to... DEPARTMENT OF HOMELAND SECURITY Federal Emergency Management Agency 44 CFR Part 65 [Docket ID FEMA-2011-0002] Changes in Flood Elevation Determinations AGENCY: Federal Emergency Management Agency, DHS...
Methods for structural design at elevated temperatures
NASA Technical Reports Server (NTRS)
Ellison, A. M.; Jones, W. E., Jr.; Leimbach, K. R.
1973-01-01
A procedure which can be used to design elevated temperature structures is discussed. The desired goal is to have the same confidence in the structural integrity at elevated temperature as the factor of safety gives on mechanical loads at room temperature. Methods of design and analysis for creep, creep rupture, and creep buckling are presented. Example problems are included to illustrate the analytical methods. Creep data for some common structural materials are presented. Appendix B is description, user's manual, and listing for the creep analysis program. The program predicts time to a given creep or to creep rupture for a material subjected to a specified stress-temperature-time spectrum. Fatigue at elevated temperature is discussed. Methods of analysis for high stress-low cycle fatigue, fatigue below the creep range, and fatigue in the creep range are included. The interaction of thermal fatigue and mechanical loads is considered, and a detailed approach to fatigue analysis is given for structures operating below the creep range.
Work postures and neck-shoulder pain among orchestra musicians.
Nyman, Teresia; Wiktorin, Christina; Mulder, Marie; Johansson, Yvonne Liljeholm
2007-05-01
The purpose of the present study was to identify associations between a work posture with elevated arm position, duration of active playing time, and neck-shoulder pain among orchestra musicians. In this study, with a cross-sectional study design, a total of 235 subjects from 12 Swedish orchestras were categorized into four exposure groups according to arm position and duration of active playing time. Logistic regression analysis was used to calculate odds ratios (OR) for neck-shoulder pain in the four exposure groups. A higher prevalence of neck-shoulder pain were found in the groups "elevated arm position, <2 hr per workday" [OR 4.15 (1.30-13.22)], and "elevated arm position, >3 hr per workday" [OR 5.35 (1.96-14.62)] compared to the group "neutral arm position, <2 hr per workday". Musicians working in an elevated arm position (e.g., violinists, violists, flutists, and trumpet players) had a higher prevalence of neck-shoulder pain than those working in a more neutral position.
Inhalation Toxicology. 11. The Effect of Elevated Temperature on Carbon Monoxide Toxicity
1990-12-01
DOT/FAA/AM-90/16 Inhalation Toxicology : XI. The Effect of Elevated Temperature on Carbon Office of Aviation Medicine Washington, D.C. 20591 M onoxide...Accession No. 3. Recipient’s Catalog No. DOT/FAA/AM-90/16 4. Title and Subtitie S. Report Date INHALATION TOXICOLOGY : XI. THE EFFECT OF ELEVATED December...Statement Combustion toxicology , carbon monoxide, This document is available to the public heat, thermal effects, time-to- through the National Technical
Hein, L R
2001-10-01
A set of NIH Image macro programs was developed to make qualitative and quantitative analyses from digital stereo pictures produced by scanning electron microscopes. These tools were designed for image alignment, anaglyph representation, animation, reconstruction of true elevation surfaces, reconstruction of elevation profiles, true-scale elevation mapping and, for the quantitative approach, surface area and roughness calculations. Limitations on time processing, scanning techniques and programming concepts are also discussed.
Collins, Dannie L.; Flynn, Kathleen M.
1979-01-01
This report summarizes and makes available to other investigators the measured hydraulic data collected during a series of experiments designed to study the effect of patterned bed roughness on steady and unsteady open-channel flow. The patterned effect of the roughness was obtained by clear-cut mowing of designated areas of an otherwise fairly dense coverage of coastal Bermuda grass approximately 250 mm high. All experiments were conducted in the Flood Plain Simulation Facility during the period of October 7 through December 12, 1974. Data from 18 steady flow experiments and 10 unsteady flow experiments are summarized. Measured data included are ground-surface elevations, grass heights and densities, water-surface elevations and point velocities for all experiments. Additional tables of water-surface elevations and measured point velocities are included for the clear-cut areas for most experiments. One complete set of average water-surface elevations and one complete set of measured point velocities are tabulated for each steady flow experiment. Time series data, on a 2-minute time interval, are tabulated for both water-surface elevations and point velocities for each unsteady flow experiment. All data collected, including individual records of water-surface elevations for the steady flow experiments, have been stored on computer disk storage and can be retrieved using the computer programs listed in the attachment to this report. (Kosco-USGS)
Method and apparatus for producing pyrolysis oil having improved stability
Baird, Lance A.; Brandvold, Timothy A.; Muller, Stefan
2016-12-27
Methods and apparatus to improve hot gas filtration to reduce the liquid fuel loss caused by prolonged residence time at high temperatures are described. The improvement can be obtained by reducing the residence time at elevated temperature by reducing the temperature of the pyrolysis vapor, by reducing the volume of the pyrolysis vapor at the elevated temperature, by increasing the volumetric flow rate at constant volume of the pyrolysis vapor, or by doing a combination of these.
Snow cover distribution over elevation zones in a mountainous catchment
NASA Astrophysics Data System (ADS)
Panagoulia, D.; Panagopoulos, Y.
2009-04-01
A good understanding of the elevetional distribution of snow cover is necessary to predict the timing and volume of runoff. In a complex mountainous terrain the snow cover distribution within a watershed is highly variable in time and space and is dependent on elevation, slope, aspect, vegetation type, surface roughness, radiation load, and energy exchange at the snow-air interface. Decreases in snowpack due to climate change could disrupt the downstream urban and agricultural water supplies, while increases could lead to seasonal flooding. Solar and longwave radiation are dominant energy inputs driving the ablation process. Turbulent energy exchange at the snow cover surface is important during the snow season. The evaporation of blowing and drifting snow is strongly dependent upon wind speed. Much of the spatial heterogeneity of snow cover is the result of snow redistribution by wind. Elevation is important in determining temperature and precipitation gradients along hillslopes, while the temperature gradients determine where precipitation falls as rain and snow and contribute to variable melt rates within the hillslope. Under these premises, the snow accumulation and ablation (SAA) model of the US National Weather Service (US NWS) was applied to implement the snow cover extent over elevation zones of a mountainous catchment (the Mesochora catchment in Western-Central Greece), taking also into account the indirectly included processes of sublimation, interception, and snow redistribution. The catchment hydrology is controlled by snowfall and snowmelt and the simulated discharge was computed from the soil moisture accounting (SMA) model of the US NWS and compared to the measured discharge. The elevationally distributed snow cover extent presented different patterns with different time of maximization, extinction and return during the year, producing different timing of discharge that is a crucial factor for the control and management of water resources systems.
Elevation trends and shrink-swell response of wetland soils to flooding and drying
Cahoon, Donald R.; Perez, Brian C.; Segura, Bradley D.; Lynch, James C.
2011-01-01
Given the potential for a projected acceleration in sea-level rise to impact wetland sustainability over the next century, a better understanding is needed of climate-related drivers that influence the processes controlling wetland elevation. Changes in local hydrology and groundwater conditions can cause short-term perturbations to marsh elevation trends through shrink—swell of marsh soils. To better understand the magnitude of these perturbations and their impacts on marsh elevation trends, we measured vertical accretion and elevation dynamics in microtidal marshes in Texas and Louisiana during and after the extreme drought conditions that existed there from 1998 to 2000. In a Louisiana marsh, elevation was controlled by subsurface hydrologic fluxes occurring below the root zone but above the 4 m depth (i.e., the base of the surface elevation table benchmark) that were related to regional drought and local meteorological conditions, with marsh elevation tracking water level variations closely. In Texas, a rapid decline in marsh elevation was related to severe drought conditions, which lowered local groundwater levels. Unfragmented marshes experienced smaller water level drawdowns and more rapid marsh elevation recovery than fragmented marshes. It appears that extended drawdowns lead to increased substrate consolidation making it less resilient to respond to future favorable conditions. Overall, changes in water storage lead to rapid and large short-term impacts on marsh elevation that are as much as five times greater than the long-term elevation trend, indicating the importance of long-term, high-resolution elevation data sets to understand the prolonged effects of water deficits on marsh elevation change.
The Use of Sun Elevation Angle for Stereogrammetric Boreal Forest Height in Open Canopies
NASA Technical Reports Server (NTRS)
Montesano, Paul M.; Neigh, Christopher; Sun, Guoqing; Duncanson, Laura Innice; Van Den Hoek, Jamon; Ranson, Kenneth Jon
2017-01-01
Stereogrammetry applied to globally available high resolution spaceborne imagery (HRSI; less than 5 m spatial resolution) yields fine-scaled digital surface models (DSMs) of elevation. These DSMs may represent elevations that range from the ground to the vegetation canopy surface, are produced from stereoscopic image pairs (stereo pairs) that have a variety of acquisition characteristics, and have been coupled with lidar data of forest structure and ground surface elevation to examine forest height. This work explores surface elevations from HRSI DSMs derived from two types of acquisitions in open canopy forests. We (1) apply an automated mass-production stereogrammetry workflow to along-track HRSI stereo pairs, (2) identify multiple spatially coincident DSMs whose stereo pairs were acquired under different solar geometry, (3) vertically co-register these DSMs using coincident spaceborne lidar footprints (from ICESat-GLAS) as reference, and(4) examine differences in surface elevations between the reference lidar and the co-registered HRSI DSMs associated with two general types of acquisitions (DSM types) from different sun elevation angles. We find that these DSM types, distinguished by sun elevation angle at the time of stereo pair acquisition, are associated with different surface elevations estimated from automated stereogrammetry in open canopy forests. For DSM values with corresponding reference ground surface elevation from spaceborne lidar footprints in open canopy northern Siberian Larix forests with slopes less than10, our results show that HRSI DSM acquired with sun elevation angles greater than 35deg and less than 25deg (during snow-free conditions) produced characteristic and consistently distinct distributions of elevation differences from reference lidar. The former include DSMs of near-ground surfaces with root mean square errors less than 0.68 m relative to lidar. The latter, particularly those with angles less than 10deg, show distributions with larger differences from lidar that are associated with open canopy forests whose vegetation surface elevations are captured. Terrain aspect did not have a strong effect on the distribution of vegetation surfaces. Using the two DSM types together, the distribution of DSM-differenced heights in forests (6.0 m, sigma = 1.4 m) was consistent with the distribution of plot-level mean tree heights (6.5m, sigma = 1.2 m). We conclude that the variation in sun elevation angle at time of stereo pair acquisition can create illumination conditions conducive for capturing elevations of surfaces either near the ground or associated with vegetation canopy. Knowledge of HRSI acquisition solar geometry and snow cover can be used to understand and combine stereogrammetric surface elevation estimates to co-register rand difference overlapping DSMs, providing a means to map forest height at fine scales, resolving the vertical structure of groups of trees from spaceborne platforms in open canopy forests.
Finger, E R
2001-04-15
The transmalar subperiosteal midface lift is a simple, direct-approach procedure to be performed with a meloplasty. The entry into the midface is at the site of maximum suture tension, which allows for more elevation. The skin is elevated enough to expose the entry site, which is on the zygoma just cephalad to the origins of the zygomaticus muscles. Through a small hole at that site, a periosteal elevator is used for the midface dissection. This is a blind dissection, and the technique is described. The advantages of the technique are that there is (1) no lower-lid incision or risk of an ectropion, (2) a resultant tightening and elevation of the lower lid, (3) more elevation and durability because the zygomaticus muscle origins are elevated with the periosteum and are sutured to the very substantial deep temporal fascia, (4) a simple and fast procedure, and (5) no telltale sign of a face lift. Both the superficial musculoaponeurotic system (SMAS) and the skin are substantially elevated with the transmalar subperiosteal midface lift to the extent that they should be only minimally dissected. In the author's opinion, the extended dissection of the skin and/or the SMAS does not increase the amount of tissue lift and probably reduces it in most cases, considering that the goal is a natural look and not one that appears pulled or stretched. The skin is elevated only for exposure, and the SMAS is elevated only enough to create a preauricular SMAS-platysma flap to tighten the neck. With two fewer layers of dissection, there is significantly less postoperative swelling and recovery time. The article presents the technique, the results on 272 patients over a period of 5 years, and a discussion. No patients described have had secondary procedures such as lasers, so the transmalar subperiosteal midface lift can be evaluated on its own merit.
Increased spring freezing vulnerability for alpine shrubs under early snowmelt.
Wheeler, J A; Hoch, G; Cortés, A J; Sedlacek, J; Wipf, S; Rixen, C
2014-05-01
Alpine dwarf shrub communities are phenologically linked with snowmelt timing, so early spring exposure may increase risk of freezing damage during early development, and consequently reduce seasonal growth. We examined whether environmental factors (duration of snow cover, elevation) influenced size and the vulnerability of shrubs to spring freezing along elevational gradients and snow microhabitats by modelling the past frequency of spring freezing events. We sampled biomass and measured the size of Salix herbacea, Vaccinium myrtillus, Vaccinium uliginosum and Loiseleuria procumbens in late spring. Leaves were exposed to freezing temperatures to determine the temperature at which 50% of specimens are killed for each species and sampling site. By linking site snowmelt and temperatures to long-term climate measurements, we extrapolated the frequency of spring freezing events at each elevation, snow microhabitat and per species over 37 years. Snowmelt timing was significantly driven by microhabitat effects, but was independent of elevation. Shrub growth was neither enhanced nor reduced by earlier snowmelt, but decreased with elevation. Freezing resistance was strongly species dependent, and did not differ along the elevation or snowmelt gradient. Microclimate extrapolation suggested that potentially lethal freezing events (in May and June) occurred for three of the four species examined. Freezing events never occurred on late snow beds, and increased in frequency with earlier snowmelt and higher elevation. Extrapolated freezing events showed a slight, non-significant increase over the 37-year record. We suggest that earlier snowmelt does not enhance growth in four dominant alpine shrubs, but increases the risk of lethal spring freezing exposure for less freezing-resistant species.
NASA Astrophysics Data System (ADS)
Nudurupati, S. S.; Istanbulluoglu, E.; Adams, J. M.; Hobley, D. E. J.; Gasparini, N. M.; Tucker, G. E.; Hutton, E. W. H.
2014-12-01
Topography plays a commanding role on the organization of ecohydrologic processes and resulting vegetation patterns. In southwestern United States, climate conditions lead to terrain aspect- and elevation-controlled ecosystems, with mesic north-facing and xeric south-facing vegetation types; and changes in biodiversity as a function of elevation from shrublands in low desert elevations, to mixed grass/shrublands in mid elevations, and forests at high elevations and ridge tops. These observed patterns have been attributed to differences in topography-mediated local soil moisture availability, micro-climatology, and life history processes of plants that control chances of plant establishment and survival. While ecohydrologic models represent local vegetation dynamics in sufficient detail up to sub-hourly time scales, plant life history and competition for space and resources has not been adequately represented in models. In this study we develop an ecohydrologic cellular automata model within the Landlab component-based modeling framework. This model couples local vegetation dynamics (biomass production, death) and plant establishment and competition processes for resources and space. This model is used to study the vegetation organization in a semiarid New Mexico catchment where elevation and hillslope aspect play a defining role on plant types. Processes that lead to observed plant types across the landscape are examined by initializing the domain with randomly assigned plant types and systematically changing model parameters that couple plant response with soil moisture dynamics. Climate perturbation experiments are conducted to examine the plant response in space and time. Understanding the inherently transient ecohydrologic systems is critical to improve predictions of climate change impacts on ecosystems.
NASA Technical Reports Server (NTRS)
Brenner, Anita C.; Zwally, H. Jay; Bentley, Charles R.; Csatho, Bea M.; Harding, David J.; Hofton, Michelle A.; Minster, Jean-Bernard; Roberts, LeeAnne; Saba, Jack L.; Thomas, Robert H.;
2012-01-01
The primary purpose of the GLAS instrument is to detect ice elevation changes over time which are used to derive changes in ice volume. Other objectives include measuring sea ice freeboard, ocean and land surface elevation, surface roughness, and canopy heights over land. This Algorithm Theoretical Basis Document (ATBD) describes the theory and implementation behind the algorithms used to produce the level 1B products for waveform parameters and global elevation and the level 2 products that are specific to ice sheet, sea ice, land, and ocean elevations respectively. These output products, are defined in detail along with the associated quality, and the constraints, and assumptions used to derive them.
NASA Astrophysics Data System (ADS)
Yi, D.; Kurtz, N. T.; Harbeck, J.
2017-12-01
The airborne IceBridge and spaceborne Cryosat-2 missions observe polar sea ice at different altitudes with different footprint sizes and often at different time and locations. Many studies use different retrackers to derive Cryosat-2 surface elevation, which we find causes large differences in the elevation and freeboard comparisons of IceBridge and Cryosat-2. In this study, we compare sea ice surface elevation and freeboard using 8 coincident CryoSat-2, ATM, and LVIS observations with IceBridge airplanes under flying the Cryosat-2 ground tracks. We apply identical ellipsoid, geoid model, tide model, and atmospheric correction to CryoSat-2 and IceBridge data to reduce elevation bias due to their differences. IceBridge's ATM and LVIS elevation and freeboard and Snow Radar snow depth are averaged at each CryoSat-2 footprint for comparison. The four different Cryosat-2 retrackers (ESA, GSFC, AWI, and JPL) show distinct differences in mean elevation up to 0.35 meters over leads and over floes, which suggests that systematic elevation bias exists between the retrackers. The mean IceBridge elevation over leads is within the mean elevation distribution of the four Cryosat-2 retrackers. The mean IceBridge elevation over floes is above the mean elevation distribution of the four Cryosat-2 retrackers. After removing the snow depth from IceBridge elevation, over floe, the mean elevation of IceBridge is within the mean elevation distribution of the four Cryosat-2 retrackers. By identifying the strengths and weaknesses of the retrackers, this study provides a mechanism to improve freeboard retrievals from existing methods.
NASA Astrophysics Data System (ADS)
Sandhu, Amit
A sequential quadratic programming method is proposed for solving nonlinear optimal control problems subject to general path constraints including mixed state-control and state only constraints. The proposed algorithm further develops on the approach proposed in [1] with objective to eliminate the use of a high number of time intervals for arriving at an optimal solution. This is done by introducing an adaptive time discretization to allow formation of a desirable control profile without utilizing a lot of intervals. The use of fewer time intervals reduces the computation time considerably. This algorithm is further used in this thesis to solve a trajectory planning problem for higher elevation Mars landing.
Elevated Passive Continental Margins may form much Later than the time of Rifting
NASA Astrophysics Data System (ADS)
Chalmers, J. A.; Japsen, P.; Green, P. F.; Bonow, J.; Lidmar-Bergstrom, K.
2007-12-01
Many current models of the development of elevated passive continental margins assume that they are either the remains of foot-wall uplift at the time of rifting or due to underplating by magma from a plume or other mantle source. We have studied the rift and post-rift history of such a passive margin in West and South Greenland and have concluded that the present-day elevations developed 25-60 million years after cessation of rifting and local volcanism, suggesting that additional factors need to be considered when modelling such margins. The morphology of West Greenland is similar to that of other elevated passive margins ion many parts of the world. There are high-level, large-scale, quasi-planar landscapes (planation surfaces) at altitudes of 1-2 km cut by deeply incised valleys. The gradient from the highest ground to the coast is much steeper than that away from the coast. We combined analysis of the morphology of the landscape with studies of fission tracks and the preserved stratigraphic record both on- and off-shore. Rifting and the commencement of sea-floor spreading in the Early Paleogene was accompanied by voluminous high-temperature volcanism. Kilometer-scale uplift at the time of rifting was followed shortly afterwards by kilometer-scale subsidence and possibly by transgression of marine sediments across the rift margin. The present elevated margin formed during three episodes of uplift during the Neogene, 25-60 million years after the cessation of rifting and local volcanism. The quasi-planar planation surfaces presently at 1-2 km altitude are the end-products of denudation to near sea-level in the mid- and late Cenozoic and these surfaces were uplifted to their present altitudes during the Neogene events. Rivers then incised the summit surface to form valleys that were further enlarged and deepened by glaciers. Similar elevated margins exist all around the northern North Atlantic and in many other parts of the world; eastern North America, on both sides of the South Atlantic, western India, eastern Australia, and possibly in Antarctica. Our results show that we cannot simply assume that these elevations were produced either at the time of rifting or as underplating at the time of plume impact. There is, however, no general agreement as to what caused them and we suggest that the history of these margins need to be re-assessed in the light of our results.
Elevated Passive Continental Margins may form much Later than the time of Rifting
NASA Astrophysics Data System (ADS)
Chalmers, J. A.; Japsen, P.; Green, P. F.; Bonow, J.; Lidmar-Bergstrom, K.
2004-12-01
Many current models of the development of elevated passive continental margins assume that they are either the remains of foot-wall uplift at the time of rifting or due to underplating by magma from a plume or other mantle source. We have studied the rift and post-rift history of such a passive margin in West and South Greenland and have concluded that the present-day elevations developed 25-60 million years after cessation of rifting and local volcanism, suggesting that additional factors need to be considered when modelling such margins. The morphology of West Greenland is similar to that of other elevated passive margins ion many parts of the world. There are high-level, large-scale, quasi-planar landscapes (planation surfaces) at altitudes of 1-2 km cut by deeply incised valleys. The gradient from the highest ground to the coast is much steeper than that away from the coast. We combined analysis of the morphology of the landscape with studies of fission tracks and the preserved stratigraphic record both on- and off-shore. Rifting and the commencement of sea-floor spreading in the Early Paleogene was accompanied by voluminous high-temperature volcanism. Kilometer-scale uplift at the time of rifting was followed shortly afterwards by kilometer-scale subsidence and possibly by transgression of marine sediments across the rift margin. The present elevated margin formed during three episodes of uplift during the Neogene, 25-60 million years after the cessation of rifting and local volcanism. The quasi-planar planation surfaces presently at 1-2 km altitude are the end-products of denudation to near sea-level in the mid- and late Cenozoic and these surfaces were uplifted to their present altitudes during the Neogene events. Rivers then incised the summit surface to form valleys that were further enlarged and deepened by glaciers. Similar elevated margins exist all around the northern North Atlantic and in many other parts of the world; eastern North America, on both sides of the South Atlantic, western India, eastern Australia, and possibly in Antarctica. Our results show that we cannot simply assume that these elevations were produced either at the time of rifting or as underplating at the time of plume impact. There is, however, no general agreement as to what caused them and we suggest that the history of these margins need to be re-assessed in the light of our results.
Jasmonate-mediated stomatal closure under elevated CO2 revealed by time-resolved metabolomics
USDA-ARS?s Scientific Manuscript database
Foliar stomatal movements are critical for regulating plant water status and gas exchange. Elevated carbon dioxide (CO2) concentrations are known to induce stomatal closure. However, current knowledge on CO2 signal transduction in stomatal guard cells is limited. Here we report the metabolomic respo...
Breakfast skippers display a disrupted cortisol rhythm and elevated blood pressure
USDA-ARS?s Scientific Manuscript database
Chronic stress and over-activity in the hypothalamic-pituitary-adrenal (HPA) axis may link breakfast skipping and poor cardiometabolic health. Missing the first major meal of the day in rodents prolongs elevated circulating corticosterone at a time when it’s normally decreasing. To extend these fi...
40 CFR 60.676 - Reporting and recordkeeping.
Code of Federal Regulations, 2011 CFR
2011-07-01
... elevator, bagging operation, or enclosed truck or railcar loading station: (i) The rated capacity in... following such change. At the time of such change, this screening operation, bucket elevator, or belt... hour of the replacement equipment. (2) For a screening operation: (i) The total surface area of the top...
40 CFR 60.676 - Reporting and recordkeeping.
Code of Federal Regulations, 2012 CFR
2012-07-01
... elevator, bagging operation, or enclosed truck or railcar loading station: (i) The rated capacity in... following such change. At the time of such change, this screening operation, bucket elevator, or belt... hour of the replacement equipment. (2) For a screening operation: (i) The total surface area of the top...
40 CFR 60.676 - Reporting and recordkeeping.
Code of Federal Regulations, 2014 CFR
2014-07-01
... elevator, bagging operation, or enclosed truck or railcar loading station: (i) The rated capacity in... following such change. At the time of such change, this screening operation, bucket elevator, or belt... hour of the replacement equipment. (2) For a screening operation: (i) The total surface area of the top...
40 CFR 60.676 - Reporting and recordkeeping.
Code of Federal Regulations, 2013 CFR
2013-07-01
... elevator, bagging operation, or enclosed truck or railcar loading station: (i) The rated capacity in... following such change. At the time of such change, this screening operation, bucket elevator, or belt... hour of the replacement equipment. (2) For a screening operation: (i) The total surface area of the top...
NASA Technical Reports Server (NTRS)
Wiener, Bernard; Harris, Agnes E
1950-01-01
Time histories are presented of horizontal-tail loads, elevator loads, and deformations on a jet-powered bomber during abrupt pitching maneuvers at a pressure altitude of approximately 20,000 feet. The normal and pitching accelerations measured varied from -0.90b to 3.41g and from -0.73 to 0.80 radian per second per second (sic), respectively, with a Mach number variation of from 0.40 to o.75. The maximum horizontal-tail load measured was 17,250 pounds down. The maximum elevator load was 1900 pounds up. The stabilizer twisted a maximum of 0.76 degrees leading edge down at the tip. The greatest fuselage deflection at the tail was about 1.7 inches down.
Heterogeneity in Trajectories of Child Maltreatment Severity: A Two-Part Growth Mixture Model
Yampolskaya, Svetlana; Greenbaum, Paul E.; Brown, C. Hendricks; Armstrong, Mary I.
2016-01-01
This study examined the trajectories of maltreatment severity and substantiation over a 24-month period among children (N = 82,396) with repeated maltreatment reports. Findings revealed two different longitudinal patterns. The first pattern, Elevated Severity, showed a higher level of maltreatment during the initial incident and increased maltreatment severity during subsequent incidents but the substantiation rates for this class decreased over time. The second pattern, Lowered Severity, showed a much lower level of severity, but the likelihood of substantiation increased over time. The Elevated Severity class was comprised of children with an elevated risk profile due to both individual and contextual risk factors including older age, female gender, caregivers’ substance use problems, and a higher number of previous maltreatment reports. Implications of the findings are discussed. PMID:26300381
Damschen, William C.; Galloway, Joel M.
2016-08-25
The U.S. Geological Survey, in cooperation with the Fargo Diversion Board of Authority, collected water-surface elevations during a range of discharges needed for calibration of hydrologic and hydraulic models for specific reaches of interest in water years 2014–15. These water-surface elevation and discharge measurement data were collected for design planning of diversion structures on the Red River of the North and Wild Rice River and the aqueduct/diversion structures on the Sheyenne and Maple Rivers. The Red River of the North and Sheyenne River reaches were surveyed six times, and discharges ranged from 276 to 6,540 cubic feet per second and from 166 to 2,040 cubic feet per second, respectively. The Wild Rice River reach also was surveyed six times during 2014 and 2015, and discharges ranged from 13 to 1,550 cubic feet per second. The Maple River reach was surveyed four times, and discharges ranged from 16.4 to 633 cubic feet per second. Water-surface elevation differences from upstream to downstream in the reaches ranged from 0.33 feet in the Red River of the North reach to 9.4 feet in the Maple River reach.
NASA Astrophysics Data System (ADS)
Mcveigh, H.; Waller, J. D.
2016-02-01
The Gulf of Maine is experiencing a rapid warming in sea surface temperature and a marked decrease in pH. This study aimed to quantify the impact of elevated temperature and acidification on the larval development of the iconic American lobster (Homarus americanus). Experimental conditions were reflective of current and IPCC predicted levels of temperature and pCO2 to be reached by the end of the century. Larvae were measured for growth (carapace length), development time, and survivorship over the larval duration. Treatments of elevated temperatures experienced decreased development time across the larval stages of H. americanus. Consequently mortality increased at a significantly higher rate under elevated temperature. An increase in larval mortality may decrease recruitment to the commercial fishery, thus impacting the most valuable single species in the state of Maine. Furthermore, experimental pCO2 treatments yielded a significantly decreased development time between larval stages II and III, yet did not have a significant impact on carapace length or mortality. This study indicates that warmer temperatures may have a greater influence than decreased pH on larval development and survival. Determining how this species may respond to changing climactic conditions will better inform the sustainability efforts of such a critical marine fishery.
Dead wood biomass and turnover time, measured by radiocarbon, along a subalpine elevation gradient.
Kueppers, Lara M; Southon, John; Baer, Paul; Harte, John
2004-12-01
Dead wood biomass can be a substantial fraction of stored carbon in forest ecosystems, and coarse woody debris (CWD) decay rates may be sensitive to climate warming. We used an elevation gradient in Colorado Rocky Mountain subalpine forest to examine climate and species effects on dead wood biomass, and on CWD decay rate. Using a new radiocarbon approach, we determined that the turnover time of lodgepole pine CWD (340+/-130 years) was roughly half as long in a site with 2.5-3 degrees C warmer air temperature, as that of pine (630+/-400 years) or Engelmann spruce CWD (800+/-960 and 650+/-410 years) in cooler sites. Across all sites and both species, CWD age ranged from 2 to 600 years, and turnover time was 580+/-180 years. Total standing and fallen dead wood biomass ranged from 4.7+/-0.2 to 54+/-1 Mg ha(-1), and from 2.8 to 60% of aboveground live tree biomass. Dead wood biomass increased 75 kg ha(-1) per meter gain in elevation and decreased 13 Mg ha(-1) for every degree C increase in mean air temperature. Differences in biomass and decay rates along the elevation gradient suggest that climate warming will lead to a loss of dead wood carbon from subalpine forest.
Reis, Gustavo Msm; Grigg, John; Chua, Brian; Lee, Anne; Lim, Ridia; Higgins, Ralph; Martins, Alessandra; Goldberg, Ivan; Clement, Colin I
2017-01-01
The aim of this article is to evaluate the rate of patients developing sustained elevated intraocular pressure (IOP) after ranibizumab (Lucentis) intravitreal (IVT) injections. This is a retrospective study. Charts of 192 consecutive patients receiving Lucentis for age-related macular degeneration (AMD) were retrospectively reviewed. We enrolled patients with at least two IOP measurements between injections. Elevated IOP was defined as >21 mm Hg with an increase of at least 20% from baseline. Noninjected contralateral eyes of the same patient cohort were used as control. Primary outcome was defined as elevated IOP. Secondary outcomes were presence and type of glaucoma, number of injections, and time to IOP elevation. Elevated IOP occurred at a significantly higher rate in eyes receiving IVT ranibizumab (7.47%; n = 9) compared with control (0.93%; n = 1). Patients with preexisting glaucoma or ocular hypertension (OHT) were more likely to develop elevated IOP after IVT ranibizumab injection. Intravitreal ranibizumab injections are associated with sustained IOP elevation in some eyes. Reis GMSM, Grigg J, Chua B, Lee A, Lim R, Higgins R, Martins A, Goldberg I, Clement CI. The Incidence of Intraocular Pressure Elevation following Intravitreal Ranibizumab (Lucentis) for Age-related Macular Degeneration. J Curr Glaucoma Pract 2017;11(1):3-7.
Sears, Michael W
2005-02-01
Along an elevational gradient on SW Utah, sagebrush lizards (Sceloporus graciosus) exhibit an unexpected pattern of growth. Lizards from a high elevation population grow faster than lizards from two populations at lower elevations despite shorter daily and seasonal activity. Results from a common environment study of growth suggest that the differences in growth are not due to adaptation to local environmental conditions. In this study, I test the hypothesis that higher growth rates in lizards from high elevation may be attributable to reduced resting metabolic expenditure compared to that of lizards from populations at two lower elevations. Resting metabolic rates were measured for individuals from each of the study populations across different times of day and over a broad range of temperatures. Under the same laboratory conditions, field-caught lizards from the high elevation population exhibited lower metabolic rates when compared to lizards from lower elevations. Daily resting metabolic expenditures were calculated using the observed metabolic rates coupled with estimates of daily activity. Daily resting metabolic expenditure was 50% greater for individuals from the two lower elevation populations, which could result in 12.5% more energy that could be potentially allocated to growth for lizards from high elevation. Such energetic savings may be able to explain differences in the patterns of growth observed in nature.
Mumladze, Levan; Murvanidze, Maka; Maraun, Mark
2017-07-01
Elevational gradients in species diversity and species area relationships are two well established patterns that are not mutually exclusive in space and time. Elevation and area are both considered as good proxies to detect and characterize the patterns of species diversity distribution. However, such studies are hampered by the incomplete biodiversity data available for ecologists, which may affect the pattern perceptions. Using the large dataset of oribatid mite communities sampled in Georgia, we tested the effects of altitude and area on species distribution using various approaches, while explicitly considering the biases from sampling effort. Our results showed that elevation and area are strongly correlated (with increasing absolute elevation, land area decreases) and both have strong linear effects on species diversity distribution when studied separately. Approaches based on multiple regression and direct removal of co-varied factors, indicated that the effect of area can actually override the effect of elevation in describing the oribatid species diversity distribution along with elevation. On the other hand, the bias of sampling proved significant in perception of elevational species richness pattern with less effect on elevational species area relationship. We suggest that the sampling alone may be responsible for patterns observed and thus should be considered in ecological studies when eligible.
Distribution pattern of reptiles along an eastern Himalayan elevation gradient, India
NASA Astrophysics Data System (ADS)
Chettri, Basundhara; Bhupathy, Subramanian; Acharya, Bhoj Kumar
2010-01-01
We examined the spatial distribution pattern of reptiles in an eastern Himalayan elevation gradient. The factors governing the distribution have been assessed with emphasis on the mid-domain effect. We surveyed reptiles along the elevation gradient (300-4800 m) of the Teesta valley in Sikkim, Eastern Himalaya, India using time constrained visual encounter survey. A total of 42 species of reptiles were observed during the study, and the species richness peaked at 500-1000 m with no species beyond 3000 m. The observed pattern was consistent with estimated richness, both showing significant negative relation with elevation. Lizards showed a linear decline with elevation, whereas snakes followed a non-linear relation with peak at 500-1000 m. Observed species richness deviated significantly from that predicted by a mid-domain null model. The regression between empirical and simulated richness was not significant for total reptiles as well as lizards and snakes separately. Most species distributed in the high elevation extended towards lower elevation, but low elevation species (around 50%) were restricted below 1000 m. Deviation of empirical from predicted richness indicates that the distributions of reptile species were least governed by geographic hard boundaries. Climatic factors especially temperature explained much variation of reptiles along the Himalayan elevation gradient. Most reptiles were narrowly distributed, especially those found in low elevation indicating the importance of tropical low-land forests in the conservation of reptiles in Eastern Himalayas.
Duan, Honglang; Duursma, Remko A; Huang, Guomin; Smith, Renee A; Choat, Brendan; O'Grady, Anthony P; Tissue, David T
2014-07-01
It has been reported that elevated temperature accelerates the time-to-mortality in plants exposed to prolonged drought, while elevated [CO(2)] acts as a mitigating factor because it can reduce stomatal conductance and thereby reduce water loss. We examined the interactive effects of elevated [CO(2)] and temperature on the inter-dependent carbon and hydraulic characteristics associated with drought-induced mortality in Eucalyptus radiata seedlings grown in two [CO(2)] (400 and 640 μL L(-1)) and two temperature (ambient and ambient +4 °C) treatments. Seedlings were exposed to two controlled drying and rewatering cycles, and then water was withheld until plants died. The extent of xylem cavitation was assessed as loss of stem hydraulic conductivity. Elevated temperature triggered more rapid mortality than ambient temperature through hydraulic failure, and was associated with larger water use, increased drought sensitivities of gas exchange traits and earlier occurrence of xylem cavitation. Elevated [CO(2)] had a negligible effect on seedling response to drought, and did not ameliorate the negative effects of elevated temperature on drought. Our findings suggest that elevated temperature and consequent higher vapour pressure deficit, but not elevated [CO(2)], may be the primary contributors to drought-induced seedling mortality under future climates. © 2013 John Wiley & Sons Ltd.
Evidence that elevated CO2 levels can indirectly increase rhizosphere denitrifier activity
NASA Technical Reports Server (NTRS)
Smart, D. R.; Ritchie, K.; Stark, J. M.; Bugbee, B.
1997-01-01
We examined the influence of elevated CO2 concentration on denitrifier enzyme activity in wheat rhizoplanes by using controlled environments and solution culture techniques. Potential denitrification activity was from 3 to 24 times higher on roots that were grown under an elevated CO2 concentration of 1,000 micromoles of CO2 mol-1 than on roots grown under ambient levels of CO2. Nitrogen loss, as determined by a nitrogen mass balance, increased with elevated CO2 levels in the shoot environment and with a high NO3- concentration in the rooting zone. These results indicated that aerial CO2 concentration can play a role in rhizosphere denitrifier activity.
The response of a boreal deep-sea sponge holobiont to acute thermal stress.
Strand, R; Whalan, S; Webster, N S; Kutti, T; Fang, J K H; Luter, H M; Bannister, R J
2017-05-22
Effects of elevated seawater temperatures on deep-water benthos has been poorly studied, despite reports of increased seawater temperature (up to 4 °C over 24 hrs) coinciding with mass mortality events of the sponge Geodia barretti at Tisler Reef, Norway. While the mechanisms driving these mortality events are unclear, manipulative laboratory experiments were conducted to quantify the effects of elevated temperature (up to 5 °C, above ambient levels) on the ecophysiology (respiration rate, nutrient uptake, cellular integrity and sponge microbiome) of G. barretti. No visible signs of stress (tissue necrosis or discolouration) were evident across experimental treatments; however, significant interactive effects of time and treatment on respiration, nutrient production and cellular stress were detected. Respiration rates and nitrogen effluxes doubled in responses to elevated temperatures (11 °C & 12 °C) compared to control temperatures (7 °C). Cellular stress, as measured through lysosomal destabilisation, was 2-5 times higher at elevated temperatures than for control temperatures. However, the microbiome of G. barretti remained stable throughout the experiment, irrespective of temperature treatment. Mortality was not evident and respiration rates returned to pre-experimental levels during recovery. These results suggest other environmental processes, either alone or in combination with elevated temperature, contributed to the mortality of G. barretti at Tisler reef.
Fusion of Laser Altimetry Data with Dems Derived from Stereo Imaging Systems
NASA Astrophysics Data System (ADS)
Schenk, T.; Csatho, B. M.; Duncan, K.
2016-06-01
During the last two decades surface elevation data have been gathered over the Greenland Ice Sheet (GrIS) from a variety of different sensors including spaceborne and airborne laser altimetry, such as NASA's Ice Cloud and land Elevation Satellite (ICESat), Airborne Topographic Mapper (ATM) and Laser Vegetation Imaging Sensor (LVIS), as well as from stereo satellite imaging systems, most notably from Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) and Worldview. The spatio-temporal resolution, the accuracy, and the spatial coverage of all these data differ widely. For example, laser altimetry systems are much more accurate than DEMs derived by correlation from imaging systems. On the other hand, DEMs usually have a superior spatial resolution and extended spatial coverage. We present in this paper an overview of the SERAC (Surface Elevation Reconstruction And Change detection) system, designed to cope with the data complexity and the computation of elevation change histories. SERAC simultaneously determines the ice sheet surface shape and the time-series of elevation changes for surface patches whose size depends on the ruggedness of the surface and the point distribution of the sensors involved. By incorporating different sensors, SERAC is a true fusion system that generates the best plausible result (time series of elevation changes) a result that is better than the sum of its individual parts. We follow this up with an example of the Helmheim gacier, involving ICESat, ATM and LVIS laser altimetry data, together with ASTER DEMs.
Sosa, Victoria; Ornelas, Juan Francisco; Ramírez-Barahona, Santiago; Gándara, Etelvina
2016-01-01
Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted species remained in situ or expanded to the lowlands during glacial cycles and contracted allopatrically during the interglacials. Although the observed genetic signals of population size changes of cloud forest-adapted species including tree ferns correspond to predicted changes by Pleistocene climate change dynamics, the observed patterns of intraspecific lineage divergence showed temporal incongruence. Here we combined phylogenetic analyses, ancestral area reconstruction, and divergence time estimates with climatic and altitudinal data (environmental space) for phenotypic traits of tree fern species to make inferences about evolutionary processes in deep time. We used phylogenetic Bayesian inference and geographic and altitudinal distribution of tree ferns to investigate ancestral area and elevation and environmental preferences of Mesoamerican tree ferns. The phylogeny was then used to estimate divergence times and ask whether the ancestral area and elevation and environmental shifts were linked to climatic events and historical climatic preferences. Bayesian trees retrieved Cyathea, Alsophyla, Gymnosphaera and Sphaeropteris in monophyletic clades. Splits for species in these genera found in Mesoamerican cloud forests are recent, from the Neogene to the Quaternary, Australia was identified as the ancestral area for the clades of these genera, except for Gymnosphaera that was Mesoamerica. Climate tolerance was not divergent from hypothesized ancestors for the most significant variables or elevation. For elevational shifts, we found repeated change from low to high elevations. Our data suggest that representatives of Cyatheaceae main lineages migrated from Australia to Mesoamerican cloud forests in different times and have persisted in these environmentally unstable areas but extant species diverged recentrly from their ancestors.
2016-01-01
Background Cloud forests, characterized by a persistent, frequent or seasonal low-level cloud cover and fragmented distribution, are one of the most threatened habitats, especially in the Neotropics. Tree ferns are among the most conspicuous elements in these forests, and ferns are restricted to regions in which minimum temperatures rarely drop below freezing and rainfall is high and evenly distributed around the year. Current phylogeographic data suggest that some of the cloud forest-adapted species remained in situ or expanded to the lowlands during glacial cycles and contracted allopatrically during the interglacials. Although the observed genetic signals of population size changes of cloud forest-adapted species including tree ferns correspond to predicted changes by Pleistocene climate change dynamics, the observed patterns of intraspecific lineage divergence showed temporal incongruence. Methods Here we combined phylogenetic analyses, ancestral area reconstruction, and divergence time estimates with climatic and altitudinal data (environmental space) for phenotypic traits of tree fern species to make inferences about evolutionary processes in deep time. We used phylogenetic Bayesian inference and geographic and altitudinal distribution of tree ferns to investigate ancestral area and elevation and environmental preferences of Mesoamerican tree ferns. The phylogeny was then used to estimate divergence times and ask whether the ancestral area and elevation and environmental shifts were linked to climatic events and historical climatic preferences. Results Bayesian trees retrieved Cyathea, Alsophyla, Gymnosphaera and Sphaeropteris in monophyletic clades. Splits for species in these genera found in Mesoamerican cloud forests are recent, from the Neogene to the Quaternary, Australia was identified as the ancestral area for the clades of these genera, except for Gymnosphaera that was Mesoamerica. Climate tolerance was not divergent from hypothesized ancestors for the most significant variables or elevation. For elevational shifts, we found repeated change from low to high elevations. Conclusions Our data suggest that representatives of Cyatheaceae main lineages migrated from Australia to Mesoamerican cloud forests in different times and have persisted in these environmentally unstable areas but extant species diverged recentrly from their ancestors. PMID:27896030
Correlation between continent area and elevation
NASA Astrophysics Data System (ADS)
Zhang, Y.
2004-12-01
This presentation is motivated by the following questions: (1) What factors determine the mean elevation and thickness of an individual continent? (2) How to explain the positive correlation between the mean height and area of individual continent? (3) Given total continental crust volume, what determines the mean thickness (and hence total area) of all continents? For example, Mean thickness of all continents is about 41 km. Mean land elevation is 874 m, and mean elevation of all continents (including land areas and continental shelves and slopes to 1000 meters below sea level) is about 800 m. Could mean continental thickness have doubled and continental area have halved in the geologic past? I present a first-order model to address these issues assuming that continental mean height is the steady state height controlled by uplift and erosion. The model predicts that it takes longer time to erode a larger continent. Hence mean continental height at steady state increases as continental area increases. This prediction is consistent with the general trend between present-day continental elevation and area (except for Antarctica), and can fit the trend well. This is the first time the relation between continental area and mean elevation is quantitatively explained. The model is further applied to investigate variations of mean thickness of continental crust over the last 600 Myr over which the continental crust mass and seawater volume are assumed to be constant. Because a change in the number of continents leads to change in the area of continents, it is predicted that the mean continental thickness increases as the number of continents decreases. Nevertheless, the thickness variation is small, amounts to about 10% from one continent to six continents. Change in the number of continents leads to a sea level fluctuation of about 0.3 km, with the lowest sea level coinciding with times of supercontinents. This prediction is consistent with prominent lows in sea level curves at the times of Pangea and Rodinia. It is concluded that the number of continents played a major role in Phanerozoic sea level changes.
The association between dietary lifestyles and hepatocellular injury in Japanese workers.
Iwata, Toyoto; Arai, Kaori; Saito, Norimitsu; Murata, Katsuyuki
2013-12-01
Elevated alanine aminotransferase (ALT) in serum, relevant to nonalcoholic fatty liver disease, has been often reported from Asian countries and the U.S., and it may be associated with lifestyle behavior. To clarify whether specific dietary behavior is associated with hepatocellular injury, we explored liver markers and dietary lifestyles (e.g., breakfast-skipping, eating for lunch, and snacking) in 1,809 male employees, aged 19-59 years, belonging to a health insurance union of automobile dealerships in Japan. ALT, γ-glutamyltransferase, and asparate aminotransferase (AST) were positively correlated with age and body mass index (BMI) (P < 0.0001). Odds ratios (ORs) of instant noodle ingestion for lunch to ALT elevation (> 30 IU/L), after adjusting for possible confounders including age, BMI, and drinking, were 1.33 (95% confidence interval, 1.01-1.75) at 1-2 times/week and 1.47 (1.07-2.01) at ≥ 3 times/week, compared to those who seldom ate instant noodles. Likewise, the OR of the ingestion at ≥ 3 times/week to γ-glutamyltransferase elevation (> 50 IU/L) was 1.42 (1.02-1.99), but the OR to elevated AST (> 30 IU/L) was not statistically significant. Habitual ethanol intake was significantly associated with hepatocellular injury, though the threshold of daily ethanol intake differed among liver markers. Despite the low OR, habitual instant noodle ingestion for lunch is associated with ALT elevation. Since the average content of saturated fatty acids in instant noodles is considerably high among cereal foods in Japan, workers with this habit should be advised to avoid having unbalanced diets.
Sun, Xin; Xu, Haobo; Shen, Jing; Guo, Shuyuan; Shi, Sa; Dan, Juhua; Tian, Fang; Tian, Yanfeng; Tian, Ye
2015-01-01
Reactive oxygen species (ROS) elevation and mitochondrial membrane potential (MMP) loss have been proven recently to be involved in sonodynamic therapy (SDT)-induced macrophage apoptosis and necrosis. This study aims to develop an experimental system to monitor intracellular ROS and MMP in real-time during ultrasonic irradiation in order to achieve optimal effect in SDT. Cultured THP-1 derived macrophages were incubated with 5-aminolevulinic acid (ALA), and then sonicated at different intensities. Intracellular ROS elevation and MMP loss were detected in real-time by fluorospectrophotometer using fluorescence probe DCFH-DA and jc-1, respectively. Ultrasound at low intensities (less than 0.48W/cm(2)) had no influence on ROS and MMP in macrophages, whereas at an intensity of 0.48W/cm(2), ROS elevation and MMP loss were observed during ultrasonic irradiation. These effects were strongly enhanced in the presence of ALA. Quantitative analysis showed that ROS elevation and MMP loss monotonically increased with the rise of ultrasonic intensity between 0.48 and 1.16W/cm(2). SDT at 0.48 and 0.84W/cm(2) induced mainly apoptosis in THP-1 macrophages while SDT at 1.16W/cm(2) mainly cell necrosis. This study supports the validity and potential utility of real-time ROS and MMP detection as a dosimetric tool for the determination of optimal SDT. Copyright © 2014 Elsevier B.V. All rights reserved.
Patterns of reptile and amphibian species richness along elevational gradients in Mt. Kenya
MALONZA, Patrick Kinyatta
2015-01-01
Faunal species richness is traditionally assumed to decrease with increasing elevation and decreasing primary productivity. Species richness is reported to peak at mid-elevation. This survey examines the herpetofaunal diversity and distribution in Mt. Kenya (central Kenya) by testing the hypothesis that changes in species richness with elevation relate to elevation-dependent changes in climate. Sampling along transects from an elevation of approximately 1 700 m in Chogoria forest block (wind-ward side) and approximately 2 600 m in Sirimon block (rain shadow zone) upwards in March 2009. This starts from the forest to montane alpine zones. Sampling of reptiles and amphibians uses pitfall traps associated with drift fences, time-limited searches and visual encounter surveys. The results show that herpetofaunal richness differs among three vegetation zones along the elevation gradient. Chogoria has higher biodiversity than Sirimon. More species occur at low and middle elevations and few exist at high elevations. The trends are consistent with expected optimum water and energy variables. The lower alpine montane zone has high species richness but low diversity due to dominance of some high elevations species. Unambiguous data do not support a mid-domain effect (mid-elevation peak) because the observed trend better fits a model in which climatic variables (rainfall and temperature) control species richness, which indirectly measures productivity. It is important to continue protection of all indigenous forests, especially at low to mid elevations. These areas are vulnerable to human destruction yet are home to some endemic species. Firebreaks can limit the spread of the perennial wildfires, especially on the moorlands. PMID:26646571
Influence of hypo- and hyperthermia on death time estimation - A simulation study.
Muggenthaler, H; Hubig, M; Schenkl, S; Mall, G
2017-09-01
Numerous physiological and pathological mechanisms can cause elevated or lowered body core temperatures. Deviations from the physiological level of about 37°C can influence temperature based death time estimations. However, it has not been investigated by means of thermodynamics, to which extent hypo- and hyperthermia bias death time estimates. Using numerical simulation, the present study investigates the errors inherent in temperature based death time estimation in case of elevated or lowered body core temperatures before death. The most considerable errors with regard to the normothermic model occur in the first few hours post-mortem. With decreasing body core temperature and increasing post-mortem time the error diminishes and stagnates at a nearly constant level. Copyright © 2017 Elsevier B.V. All rights reserved.
Elevated lipoprotein (a) levels are an independent risk factor for retinal vein occlusion.
Kuhli-Hattenbach, Claudia; Miesbach, Wolfgang; Lüchtenberg, Marc; Kohnen, Thomas; Hattenbach, Lars-Olof
2017-03-01
To investigate the prevalence of lipoprotein (a) [Lp(a)] and other thrombophilic disorders among retinal vein occlusion (RVO) patients with regard to age and various risk factors. We retrospectively reviewed the medical records of 100 patients with central, hemicentral or branch RVO who had undergone routine thrombophilia screening. Data were compared with 100 controls. Both cohorts were divided into three subgroups (≤45 years, >45-≤60 years or >60 years), depending on the patients' age at the time of the RVO or a previous thromboembolic event. Elevated Lp(a) plasma levels were significantly more prevalent among RVO patients than among controls (p < 0.0001; OR: 4.8). Moreover, we determined age ≤60 years by the time of the first thromboembolic event as a strong predictor of elevated Lp(a) (p = 0.0002). The coincidence of elevated Lp(a) with other coagulation disorders further increased the OR for RVO to 9.3 (95% CI 2.1-41.8). Multivariate analysis revealed the presence of cardiovascular risk factors (OR: 3.1, p = 0.0004), elevated lipoprotein (a) levels (OR: 5.2, p = 0.0001) and increased factor VIII activity (OR: 5.9, p = 0.001) as independent risk factors for the development of RVO among patients. Our results indicate that elevated plasma levels of Lp(a) are associated with the development of RVO. Selective screening of young patients and subjects with a personal or family history of thromboembolism may be helpful in identifying RVO patients with elevated Lp(a). © 2016 Acta Ophthalmologica Scandinavica Foundation. Published by John Wiley & Sons Ltd.
Carrico, Amanda R.; Spoden, Micajah; Wallston, Kenneth A.; Vandenbergh, Michael P.
2013-01-01
Multiple government and health organizations recommend the use of warm or hot water in publications designed to educate the public on best practices for washing one’s hands. This is despite research suggesting that the use of an elevated water temperature does not improve handwashing efficacy, but can cause hand irritation. There is reason to believe that the perception that warm or hot water is more effective at cleaning one’s hands is pervasive, and may be one factor that is driving up unnecessary energy consumption and greenhouse gas emissions. We examine handwashing practices and beliefs about water temperature using a survey of 510 adults in the United States. The survey included measures of handwashing frequency, duration, the proportion of time an elevated temperature was used, and beliefs about water temperature and handwashing efficacy. We also estimate the energy consumed and resultant carbon dioxide equivalent emissions (CO2eq) in the U.S. due to the use of elevated temperatures during handwashing. Participants used an elevated temperature 64% of the time, causing 6.3 million metric tons (MMt) of CO2eq which is 0.1% of total annual emissions and 0.3% of commercial and residential sector emissions. Roughly 69% of the sample believed that elevated temperatures improve handwashing efficacy. Updating these beliefs could prevent 1 MMt of CO2eq annually, exceeding the total emissions from many industrial sources in the U.S. including the Lead and Zinc industries. In addition to causing skin irritation, the recommendation to use an elevated temperature during handwashing contributes to another major threat to public health—climate change. Health and consumer protection organizations should consider advocating for the use of a “comfortable” temperature rather than warm or hot water. PMID:23814480
Segev, Danny; Levi, Retsef; Dunn, Peter F; Sandberg, Warren S
2012-06-01
Transportation of patients is a key hospital operational activity. During a large construction project, our patient admission and prep area will relocate from immediately adjacent to the operating room suite to another floor of a different building. Transportation will require extra distance and elevator trips to deliver patients and recycle transporters (specifically: personnel who transport patients). Management intuition suggested that starting all 52 first cases simultaneously would require many of the 18 available elevators. To test this, we developed a data-driven simulation tool to allow decision makers to simultaneously address planning and evaluation questions about patient transportation. We coded a stochastic simulation tool for a generalized model treating all factors contributing to the process as JAVA objects. The model includes elevator steps, explicitly accounting for transporter speed and distance to be covered. We used the model for sensitivity analyses of the number of dedicated elevators, dedicated transporters, transporter speed and the planned process start time on lateness of OR starts and the number of cases with serious delays (i.e., more than 15 min). Allocating two of the 18 elevators and 7 transporters reduced lateness and the number of cases with serious delays. Additional elevators and/or transporters yielded little additional benefit. If the admission process produced ready-for-transport patients 20 min earlier, almost all delays would be eliminated. Modeling results contradicted clinical managers' intuition that starting all first cases on time requires many dedicated elevators. This is explained by the principle of decreasing marginal returns for increasing capacity when there are other limiting constraints in the system.
Anderson, Jill T; Gezon, Zachariah J
2015-04-01
Environmental variation often induces shifts in functional traits, yet we know little about whether plasticity will reduce extinction risks under climate change. As climate change proceeds, phenotypic plasticity could enable species with limited dispersal capacity to persist in situ, and migrating populations of other species to establish in new sites at higher elevations or latitudes. Alternatively, climate change could induce maladaptive plasticity, reducing fitness, and potentially stalling adaptation and migration. Here, we quantified plasticity in life history, foliar morphology, and ecophysiology in Boechera stricta (Brassicaceae), a perennial forb native to the Rocky Mountains. In this region, warming winters are reducing snowpack and warming springs are advancing the timing of snow melt. We hypothesized that traits that were historically advantageous in hot and dry, low-elevation locations will be favored at higher elevation sites due to climate change. To test this hypothesis, we quantified trait variation in natural populations across an elevational gradient. We then estimated plasticity and genetic variation in common gardens at two elevations. Finally, we tested whether climatic manipulations induce plasticity, with the prediction that plants exposed to early snow removal would resemble individuals from lower elevation populations. In natural populations, foliar morphology and ecophysiology varied with elevation in the predicted directions. In the common gardens, trait plasticity was generally concordant with phenotypic clines from the natural populations. Experimental snow removal advanced flowering phenology by 7 days, which is similar in magnitude to flowering time shifts over 2-3 decades of climate change. Therefore, snow manipulations in this system can be used to predict eco-evolutionary responses to global change. Snow removal also altered foliar morphology, but in unexpected ways. Extensive plasticity could buffer against immediate fitness declines due to changing climates. © 2014 John Wiley & Sons Ltd.
NASA Astrophysics Data System (ADS)
Austermann, Jacqueline; Pollard, David; Mitrovica, Jerry X.; Moucha, Robert; Forte, Alessandro M.; DeConto, Robert M.
2015-04-01
Reconstructions of the Antarctic ice sheet over long timescales (i.e. Myrs) require estimates of bedrock elevation through time. Ice sheet models have accounted, with varying levels of sophistication, for changes in the bedrock elevation due to glacial isostatic adjustment (GIA), but they have neglected other processes that may perturb topography. One notable example is dynamic topography, the deflection of the solid surface of the Earth due to convective flow within the mantle. Numerically predicted changes in dynamic topography have been used to correct paleo shorelines for this departure from eustasy, but the effect of such changes on ice sheet stability is unknown. In this study we use numerical predictions of time-varying dynamic topography to reconstruct bedrock elevation below the Antarctic ice sheet during the mid Pliocene warm period (~3 Ma). Moreover, we couple this reconstruction to a three-dimensional ice sheet model to explore the impact of dynamic topography on the evolution of the Antarctic ice sheet since the Pliocene. Our modeling indicates significant uplift in the area of the Transantarctic Mountains (TAM) and the adjacent Wilkes basin. This predicted uplift, which is at the lower end of geological inferences of uplift of the TAM, implies a lower elevation of the basin in the Pliocene. Relative to simulations that do not include dynamic topography, the lower elevation leads to a smaller Antarctic Ice Sheet volume and a more significant retreat of the grounding line in the Wilkes basin, both of which are consistent with offshore sediment core data. We conclude that reconstructions of the Antarctic Ice Sheet during the mid-Pliocene warm period should be based on bedrock elevation models that include the impact of both GIA and dynamic topography.
Martí-Hereu, L; Arreciado Marañón, A
The semirecumbent position is a widespread recommendation for the prevention of pneumonia associated with mechanical ventilation. To identify the time of elevation of head of bed for patients under mechanical ventilation and the factors related to such elevation in an intensive care unit. An observational, descriptive cross-sectional study. Conducted in an intensive care unit of a tertiary hospital from April to June 2015. The studied population were mechanically ventilated patients. Daily hours in which patients remained with the head of the bed elevated (≥30°), socio-demographic data and clinical variables were recorded. 261 head elevation measurements were collected. The average daily hours that patients remained at ≥30° was 16h28' (SD ±5h38'), equivalent to 68.6% (SD ±23.5%) of the day. Factors related to elevations ≥30° for longer were: enteral nutrition, levels of deep sedation, cardiac and neurocritical diagnostics. Factors that hindered the position were: sedation levels for agitation and abdominal pathologies. Sex, age and ventilation mode did not show a significant relationship with bed head elevation. Although raising the head of the bed is an easy to perform, economical and measurable preventive measure, its compliance is low due to specific factors specific related o the patient's clinical condition. Using innovations such as continuous measurement of the head position helps to evaluate clinical practice and allows to carry out improvement actions whose impact is beneficial to the patient. Copyright © 2017 Sociedad Española de Enfermería Intensiva y Unidades Coronarias (SEEIUC). Publicado por Elsevier España, S.L.U. All rights reserved.
NASA Astrophysics Data System (ADS)
Csatho, B. M.; Schenk, A.; Nagarajan, S.; Babonis, G. S.
2010-12-01
Investigations of ice sheet mass balance and the changing dynamics of outlet glaciers have been hampered by the lack of comprehensive data. In recent years, this situation has been remedied. Satellite laser altimetry data from the Ice Cloud and land Elevation Satellite mission (ICESat), combined with airborne laser altimetry, provide accurate measurements of surface elevation changes, and surface velocities derived from various satellite platforms yield crucial information on changing glacier dynamics. Taken together, a rich and diverse data set is emerging that allows for characterizing the spatial and temporal evolution of ice sheets and outlet glaciers. In particular, it enables quantitative studies of outlet glaciers undergoing rapid and complex changes. Although airborne and laser altimetry have been providing precise measurements of ice sheet topography since the early 1990s, determining detailed and accurate spatial and temporal distribution of surface changes remains a challenging problem. We have developed a new, comprehensive method, called Surface Elevation Reconstruction And Change detection (SERAC), which estimates surface changes by a simultaneous reconstruction of surface topography from fused multisensor data. The mathematical model is based on the assumption that for a small surface area, only the absolute elevation changes over time but not the shape of the surface patch. Therefore, laser points of all time epochs contribute to the shape parameters; points of each time period determine the absolute elevation of the surface patch at that period. This method provides high-resolution surface topography, precise changes and a rigorous error estimate of the quantities. By using SERAC we combined ICESat and ATM laser altimetry data to determine the evolution of surface change rates of the whole Greenland Ice Sheet between 2003 and 2009 on a high-resolution grid. Our reconstruction, consistent with GRACE results, shows ice sheet thinning propagating along the NW coast, and thinning expanding to higher elevations in SW and N Greenland. Several outlet glaciers, for example Humboldt and Petermann glaciers in NW Greenland and Kangilerngata Sermia in W Greenland exhibit a complex spatial and temporal pattern of thickening-thinning with regions of thickening observed at lower elevations. We will examine the thickening and thinning history and the record of surface velocity of these glaciers to investigate the processes responsible for initiating and sustaining these changes. Moreover, by analyzing the detailed surface elevation change history along flowlines or across drainage basins, the propagation of thinning following perturbations at the glacier terminus can be investigated. Results, depicting the evolution of surface elevation changes of three major outlet glaciers, Jakobshavn, Helheim and Kangerlussuaq glaciers, will be shown.
Serum biochemical markers in lung cancer.
Burt, R. W.; Ratcliffe, J. G.; Stack, B. H.; Cuthbert, J.; Kennedy, R. S.; Corker, C. S.; Franchimont, P.; Spilg, W. G.; Stimson, W. H.
1978-01-01
The prevalence of elevated serum levels of 5 potential tumour-associated antigens was determined in patients with lung cancer sampled at the time of initial presentation, using age- and sex-matched patients with benign lung disease as controls. Elevated levels (greater than upper 95th centile of controls) were found as follows: carcinoembryonic antigen (CEA), 17%; pregnancy-associated alpha-macroglobulin (PAM), 16%; casein 14%; human chorionic gonadotrophin (HCG) 6%; alpha-foetoprotein (AFP), 1.5%. The prevalence of elevated CEA levels (but not other markers) was higher in patients with evidence of extra-thoracic tumour spread (23%) mainly due to anaplastic tumours and adenocarcinomas. A degree of concordance of elevated marker levels occurred with CEA, HCG, casein and AFP, but there was a striking discordance of elevated CEA and PAM levels. Simultaneous assays of CEA and PAM will detect the majority of patients with elevations of any of the markers studied, and are likely to be the most useful biochemical markers in following the response of lung tumours to therapy. PMID:77672
Zhang, Huan; Song, Donghan; An, Lina
2016-05-01
To study the effect of a real-time tele-transmission system of 12-lead electrocardiogram on door-to-balloon time in athletes with ST-elevation myocardial infarction. A total of 60 athletes with chest pain diagnosed as ST-elevation myocardial infarction (STEMI) from our hospital were randomly divided into group A (n=35) and group B (n=25), the patients in group A transmitted the real-time tele-transmission system of 12-lead electrocardiogram to the chest pain center before arriving in hospital, however, the patients in group B not. The median door-to-balloon time was significant shorter in-group A than group B (38min vs 94 min, p<0.01) and the ratio of door-to-balloon time below 90 min was remarkable higher in-group A (94.2% vs 60%, p<0.01). The rate of catheter laboratory occupied was 5.7% in-group A and 40% in group B respectively (p=0.001). There was no statistically difference in mortality between the two groups (5.7% vs 4%, p>0.05). The median length of stay was significant reduced in-group A (5 days vs 7 days, p<0.01). Real-time tele-transmission system of 12 lead electrocardiogram is beneficial to the pre-hospital diagnosis of STEMI.
Heat shock response and mammal adaptation to high elevation (hypoxia).
Wang, Xiaolin; Xu, Cunshuan; Wang, Xiujie; Wang, Dongjie; Wang, Qingshang; Zhang, Baochen
2006-10-01
The mammal's high elevation (hypoxia) adaptation was studied by using the immunological and the molecular biological methods to understand the significance of Hsp (hypoxia) adaptation in the organic high elevation, through the mammal heat shock response. (1) From high elevation to low elevation (natural hypoxia): Western blot and conventional RT-PCR and real-time fluorescence quota PCR were adopted. Expression difference of heat shock protein of 70 (Hsp70) and natural expression of brain tissue of Hsp70 gene was determined in the cardiac muscle tissue among the different elevation mammals (yak). (2) From low elevation to high elevation (hypoxia induction): The mammals (domestic rabbits) from the low elevation were sent directly to the areas with different high elevations like 2300, 3300 and 5000 m above sea level to be raised for a period of 3 weeks before being slaughtered and the genetic inductive expression of the brain tissue of Hsp70 was determined with RT-PCR. The result indicated that all of the mammals at different elevations possessed their heat shock response gene. Hsp70 of the high elevation mammal rose abruptly under stress and might be induced to come into being by high elevation (hypoxia). The speedy synthesis of Hsp70 in the process of heat shock response is suitable to maintain the cells' normal physiological functions under stress. The Hsp70 has its threshold value. The altitude of 5000 m above sea level is the best condition for the heat shock response, and it starts to reduce when the altitude is over 6000 m above sea level. The Hsp70 production quantity and the cell hypoxia bearing capacity have their direct ratio.
NASA Astrophysics Data System (ADS)
Lovette, J. P.; Lenhardt, W. C.; Blanton, B.; Duncan, J. M.; Stillwell, L.
2017-12-01
The National Water Model (NWM) has provided a novel framework for near real time flood inundation mapping across CONUS at a 10m resolution. In many regions, this spatial scale is quickly being surpassed through the collection of high resolution lidar (1 - 3m). As one of the leading states in data collection for flood inundation mapping, North Carolina is currently improving their previously available 20 ft statewide elevation product to a Quality Level 2 (QL2) product with a nominal point spacing of 0.7 meters. This QL2 elevation product increases the ground points by roughly ten times over the previous statewide lidar product, and by over 250 times when compared to the 10m NED elevation grid. When combining these new lidar data with the discharge estimates from the NWM, we can further improve statewide flood inundation maps and predictions of at-risk areas. In the context of flood risk management, these improved predictions with higher resolution elevation models consistently represent an improvement on coarser products. Additionally, the QL2 lidar also includes coarse land cover classification data for each point return, opening the possibility for expanding analysis beyond the use of only digital elevation models (e.g. improving estimates of surface roughness, identifying anthropogenic features in floodplains, characterizing riparian zones, etc.). Using the NWM Height Above Nearest Drainage approach, we compare flood inundation extents derived from multiple lidar-derived grid resolutions to assess the tradeoff between precision and computational load in North Carolina's coastal river basins. The elevation data distributed through the state's new lidar collection program provide spatial resolutions ranging from 5-50 feet, with most inland areas also including a 3 ft product. Data storage increases by almost two orders of magnitude across this range, as does processing load. In order to further assess the validity of the higher resolution elevation products on flood inundation, we examine the NWM outputs from Hurricane Matthew, which devastated southeastern North Carolina in October 2016. When compared with numerous surveyed high water marks across the coastal plain, this assessment provides insight on the impacts of grid resolution on flood inundation extent.
Elevation Gradients and Climatic Consequences
NASA Astrophysics Data System (ADS)
Redmond, K. T.
2006-12-01
Steep topography usually results in gradients in surface meteorological elements. Sometimes these gradients are extremely sharp. Frequent or persistent gradients are expressed in climatic statistics as well. Most commonly, higher elevations are wetter and cooler than lower elevations. The magnitude of these climate gradients vary both spatially and temporally, generally on smaller scales for the former and on a greater variety of scales for the latter. Orographic contributions to precipitation vary on hourly to annual scales, and temperature inversions of different durations can alter or reverse the vertical temperature lapse rate normally found in the atmosphere. The presence of these factors affects the probability distributions of climate elements as a function of elevation. This leads in turn to consequences for ecology, resource management, and data. Orographic enhancement of Sierra precipitation varies by a factor of about three on seasonal time scales, and more on shorter scales. Particularly strong gradients in temperature climate are observed along the California coast, resulting in large changes in long-term climatological probability distributions over quite short distances in elevation. These have significant implications for plant life. For specific noteworthy events, such as the California heat wave of July 2006, striking differences were seen over a horizontal distance of merely 2-3 km along the Big Sur Coast, related entirely to elevation. There is evidence of differential warming with elevation between California's Central Valley and the Sierra Nevada. As a practical matter, the three-dimensional correlation fields of weather and climate elements in topographically diverse regions, on differing time scales, have complex structure, but also have certain regularities. This makes quality control of weather and climate data sets in highly diverse topography much more challenging. Quality control decisions that do not properly take this correlation structure (which varies in time) into account can result in degraded data sets, a variety of Type I and Type II errors, and paradoxically, hinder or prevent the discovery and description of the effects of climate gradients by incorrectly altering the data sets needed to uncover and quantify the relationships.
Growth and demography of Pinaleno high elevation forests
Christopher O' Connor; Donald A. Falk; Ann M. Lynch; Craig P. Wilcox; Thomas W. Swetnam; Tyson L. Swetnam
2010-01-01
The project goal is to understand how multiple disturbance events including fire, insect outbreaks, and climate variability interact in space and time, and how they combine to influence forest species composition, spatial structure, and tree population dynamics in high elevation forests of the Pinaleno Mountains. Information from each of these components is needed in...
3D Elevation Program—Virtual USA in 3D
Lukas, Vicki; Stoker, J.M.
2016-04-14
The U.S. Geological Survey (USGS) 3D Elevation Program (3DEP) uses a laser system called ‘lidar’ (light detection and ranging) to create a virtual reality map of the Nation that is very accurate. 3D maps have many uses with new uses being discovered all the time.
Program For Tracking The Sun From The Moon
NASA Technical Reports Server (NTRS)
Woods, Warren K.; Spires, Dustin S.
1995-01-01
SUNTRACKER program computes azimuth and elevation angles of Sun, as viewed from given position on Moon, during time defined by user. Program gets selenographic (moon-centered) position of Sun at given Julian date, then converts selenographic position of Sun into azimuth and elevation at given position on Moon. Written in FORTRAN 77.
Environmental harshness, heat stress, and Marmota flaviventris.
Webb, D R
1979-01-01
Yellow-bellied marmots (Marmota flaviventris) were studied at three sites in central Oregon. Juveniles substantially reduced their foraging activity when equivalent black-body temperatures exceeded their upper critical temperature. Inclusion of heat stress into estimates of environmental harshness drastically reduced the differences in available foraging time between high elevation and low elevation sites.
33 CFR 208.26 - Altus Dam and Reservoir, North Fork Red River, Okla.
Code of Federal Regulations, 2010 CFR
2010-07-01
... elevation forecast indicates that this operation will result in a reservoir level exceeding elevation 1562... and reservoir from major damage. (j) Any time that the Bureau of Reclamation determines that operation... 33 Navigation and Navigable Waters 3 2010-07-01 2010-07-01 false Altus Dam and Reservoir, North...
33 CFR 208.26 - Altus Dam and Reservoir, North Fork Red River, Okla.
Code of Federal Regulations, 2011 CFR
2011-07-01
... elevation forecast indicates that this operation will result in a reservoir level exceeding elevation 1562... and reservoir from major damage. (j) Any time that the Bureau of Reclamation determines that operation... 33 Navigation and Navigable Waters 3 2011-07-01 2011-07-01 false Altus Dam and Reservoir, North...
Profile surveys along Henrys Fork, Idaho, and Logan River and Blacksmith Fork, Utah
Herron, William Harrison
1916-01-01
In order to determine the location of undeveloped water powers the United States Geological Survey has from time to time, alone and in cooperation with State organizations, made surveys and profiles of some of the rivers of the United States that are adapted to the development of power by low or medium heads of 20 to 100 feet.The surveys are made by means of plane table and stadia. Elevations are based on heights derived from primary or precise levels of the United States Geological Survey. The maps/are made in the field, and show not only the outlines of the river banks, the islands, the positions of rapids/falls, shoals, and existing dams, and the crossings of all ferries and roads, but the contours of banks to an elevation high enough to indicate the possibility of using the stream. The elevations of the various bench marks left are noted on the field sheets in their proper positions. The figures given with the gaging stations shown on the maps indicate the elevation of the zero of the gage.
110K Bi-Sr-Ca-Cu-O superconductor oxide and method for making same
Veal, B.W.; Downey, J.W.; Lam, D.J.; Paulikas, A.P.
1992-12-22
A superconductor is disclosed consisting of a sufficiently pure phase of the oxides of Bi, Sr, Ca, and Cu to exhibit a resistive zero near 110K resulting from the process of forming a mixture of Bi[sub 2]O[sub 3], SrCO[sub 3], CaCO[sub 3] and CuO into a particulate compact wherein the atom ratios are Bi[sub 2], Sr[sub 1.2-2.2], Ca[sub 1.8-2.4], Cu[sub 3]. Thereafter, heating the particulate compact rapidly in the presence of oxygen to an elevated temperature near the melting point of the oxides to form a sintered compact, and then maintaining the sintered compact at the elevated temperature for a prolonged period of time. The sintered compact is cooled and reground. Thereafter, the reground particulate material is compacted and heated in the presence of oxygen to an elevated temperature near the melting point of the oxide and maintained at the elevated temperature for a time sufficient to provide a sufficiently pure phase to exhibit a resistive zero near 110K. 7 figs.
Cryogenic and elevated temperature strengths of an Al-Zn-Mg-Cu alloy modified with Sc and Zr
NASA Astrophysics Data System (ADS)
Senkova, S. V.; Senkov, O. N.; Miracle, D. B.
2006-12-01
The effect of minor additions of Sc and Zr on tensile properties of two developmental Al-Zn-Mg-Cu alloys was studied in the temperature range -196°C to 300°C. Due to the presence of Sc and Zr in a fine dispersoid form, both low-temperature and elevated temperature strengths of these alloys are much higher than those of similar 7000 series alloys that do not contain these elements. After short holding times (up to 10 hours) at 205°C, the strength of these alloys is higher than those of high-temperature Al alloys 2219-T6 and 2618-T6; however, the latter alloys show better strength after longer holding times. It is suggested that additional alloying of the Sc-containing Al-Zn-Mg-Cu alloys with other dispersoid-forming elements, such as Ni, Fe, Mn, and Si, with a respective decrease in the amounts of Zn and Mg may further improve the elevated temperature strength and decrease the loss of strength with extended elevated temperature exposure.
Test anxiety and cardiovascular responses to daily academic stressors.
Conley, Kristen M; Lehman, Barbara J
2012-02-01
Routine academic events may cause stress and produce temporary elevations in blood pressure. Students who experience test anxiety may be especially prone to cardiovascular activation in response to academic stress. This study drew on self-reported stress and ambulatory blood pressure measurements provided by 99 undergraduate participants (30% men, mean age=21 years) who participated over 4 days. Posture, activity level, recent consumption and the previous same-day reading were considered as covariates in a series of hierarchical linear models. Results indicate elevations in systolic blood pressure at times of acute academic stressors; neither diastolic blood pressure nor heart rate was linked with academic stress. In addition, those participants higher in test anxiety exhibited especially pronounced elevations in systolic blood pressure during times of acute academic stress. This research suggests that everyday academic stressors are linked with temporary increases in blood pressure and that test anxiety may contribute to these elevations. Test anxiety has implications for future academic and job success, and cardiovascular responses to everyday stress may contribute to health problems later in life. Copyright © 2011 John Wiley & Sons, Ltd.
Flight Test Results of a Synthetic Vision Elevation Database Integrity Monitor
NASA Technical Reports Server (NTRS)
deHaag, Maarten Uijt; Sayre, Jonathon; Campbell, Jacob; Young, Steve; Gray, Robert
2001-01-01
This paper discusses the flight test results of a real-time Digital Elevation Model (DEM) integrity monitor for Civil Aviation applications. Providing pilots with Synthetic Vision (SV) displays containing terrain information has the potential to improve flight safety by improving situational awareness and thereby reducing the likelihood of Controlled Flight Into Terrain (CFIT). Utilization of DEMs, such as the digital terrain elevation data (DTED), requires a DEM integrity check and timely integrity alerts to the pilots when used for flight-critical terrain-displays, otherwise the DEM may provide hazardous misleading terrain information. The discussed integrity monitor checks the consistency between a terrain elevation profile synthesized from sensor information, and the profile given in the DEM. The synthesized profile is derived from DGPS and radar altimeter measurements. DEMs of various spatial resolutions are used to illustrate the dependency of the integrity monitor s performance on the DEMs spatial resolution. The paper will give a description of proposed integrity algorithms, the flight test setup, and the results of a flight test performed at the Ohio University airport and in the vicinity of Asheville, NC.
110K Bi-Sr-Ca-Cu-O superconductor oxide and method for making same
Veal, Boyd W.; Downey, John W.; Lam, Daniel J.; Paulikas, Arvydas P.
1992-01-01
A superconductor consisting of a sufficiently pure phase of the oxides of Bi, Sr, Ca, and Cu to exhibit a resistive zero near 110K resulting from the process of forming a mixture of Bi.sub.2 O.sub.3, SrCO.sub.3, CaCO.sub.3 and CuO into aparticulate compact wherein the atom ratios are Bi.sub.2, Sr.sub.1.2-2.2, Ca.sub.1.8-2.4, Cu.sub.3. Thereafter, heating the particulate compact rapidly in the presence of oxygen to an elevated temperature near the melting point of the oxides to form a sintered compact, and then maintaining the sintered compact at the elevated temperature for a prolonged period of time. The sintered compact is cooled and reground. Thereafter, the reground particulate material is compacted and heated in the presence of oxygen to an elevated temperature near the melting point of the oxide and maintained at the elevated temperature for a time sufficient to provide a sufficiently pure phase to exhibit a resistive zero near 110K.
[Interventional therapy of acute myocardial infarction].
Zahn, R; Zeymer, U
2008-09-01
Currently an acute myocardial infarction has to be differentiated into ST-elevation myocardial infarction (STEMI) or non ST-elevation myocardial infarction (NSTEMI). However, there exists another definition of acute coronary syndromes (ACS), which is more important in clinical practice, for all recommendations from the guidelines of the cardiac societies concerning the invasive strategies rely on this one. Here one has to differentiate an ACS with ST-elevation (STE-ACS = STEMI) from an ACS without ST-elevation (NSTE-ACS). The last one is further divided into an NSTE-ACS with or without high risk. In patients with an NSTE-ACS with high risk an early invasive strategy is recommended within 72 h after the diagnosis. In patients with an NSTE-ACS without high risk a more conservative approach can be pursued. In STE-ACS patients primary angioplasty is the reperfusion therapy of choice, if it can be performed in a timely fashion within 2 h after diagnosis at an interventional centre with experienced interventionalists and short "door-to-balloon" times. In Germany this goal is achievable almost everywhere. Therefore it is currently the most important task to establish local networks to reach this goal.
Temporal and spatial variability in thalweg profiles of a gravel-bed river
Madej, Mary Ann
1999-01-01
This study used successive longitudinal thalweg profiles in gravel-bed rivers to monitor changes in bed topography following floods and associated large sediment inputs. Variations in channel bed elevations, distributions of residual water depths, percentage of channel length occupied by riffles, and a spatial autocorrelation coefficient (Moran's I) were used to quantify changes in morphological diversity and spatial structure in Redwood Creek basin, northwestern California. Bed topography in Redwood Creek and its major tributaries consists primarily of a series of pools and riffles. The size, frequency and spatial distribution of the pools and riffles have changed significantly during the past 20 years. Following large floods and high sediment input in Redwood Creek and its tributaries in 1975, variation in channel bed elevations was low and the percentage of the channel length occupied by riffles was high. Over the next 20 years, variation in bed elevations increased while the length of channel occupied by riffles decreased. An index [(standard deviation of residual water depth/bankfull depth) × 100] was developed to compare variations in bed elevation over a range of stream sizes, with a higher index being indicative of greater morphological diversity. Spatial autocorrelation in the bed elevation data was apparent at both fine and coarse scales in many of the thalweg profiles and the observed spatial pattern of bed elevations was found to be related to the dominant channel material and the time since disturbance. River reaches in which forced pools dominated, and in which large woody debris and bed particles could not be easily mobilized, exhibited a random distribution of bed elevations. In contrast, in reaches where alternate bars dominated, and both wood and gravel were readily transported, regularly spaced bed topography developed at a spacing that increased with time since disturbance. This pattern of regularly spaced bed features was reversed following a 12-year flood when bed elevations became more randomly arranged.
Salas-Morales, Silvia H; Meave, Jorge A; Trejo, Irma
2015-12-01
Globally, climate is a fundamental driver of plant species' geographical distributions, yet we still lack a good understanding of climatic variation on tropical mountains and its consequences for elevational floristic patterns. In a seasonally dry region of southern Mexico, we analysed meteorological patterns along a large elevational gradient (0-3670 m a.s.l.) and examined their relationship with changes in floristic richness. Meteorological patterns were characterised using two data sources. First, climatic information was extracted from cartography and records from a few existing meteorological stations. Additionally, air temperature and humidity were recorded hourly during 1 year with data loggers, at sites representing 200-m elevation increments. Floristic information was extracted from a database containing 10,124 records of plant collections, and organized in 200-m elevational belts. Climatic charts distinguished three climate types along the gradient, all with marked rainfall seasonality, but these bore little correspondence with the information obtained with the data loggers. Mean annual air temperature decreased with increasing elevation (lapse rate of 0.542 °C 100 m(-1)). Thermal oscillation was minimum around 1400 m and increased towards both extremes of the gradient. Relative humidity opposed this pattern, with maxima between 800 and 1800 m, decreasing towards the highest elevations. An analysis of temperature frequency distributions revealed meteorological features undetectable from the annual or monthly means of this variable; despite an overall gradual transition of the proportions of time recorded at different temperatures, some changes did not conform to this pattern. The first discontinuity occurred between 1000-1200 m, where dominant temperatures shifted abruptly; also noticeable was an abrupt increase of the proportion of time elapsed at 0.1-10 °C between 2400 and 2600 m. Air temperature appears to be the most influential climatic factor driving elevational variation of plant species richness in this region.
Antarctic Ice-Sheet Mass Balance from Satellite Altimetry 1992 to 2001
NASA Technical Reports Server (NTRS)
Zwally, H. Jay; Brenner, Anita C.; Cornejo, Helen; Giovinetto, Mario; Saba, Jack L.; Yi, Donghui
2003-01-01
A major uncertainty in understanding the causes of the current rate of sea level rise is the potential contributions from mass imbalances of the Greenland and Antarctic ice sheets. Estimates of the current mass balance of the Antarctic ice sheet are derived from surface- elevation changes obtained from 9 years of ERS - 1 & 2 radar altimeter data. Elevation time-series are created from altimeter crossovers among 90-day data periods on a 50 km grid to 81.5 S. The time series are fit with a multivariate linear/sinusoidal function to give the average rate of elevation change (dH/dt). On the major Rome-Filchner, Ross, and Amery ice shelves, the W d t are small or near zero. In contrast, the ice shelves of the Antarctic Peninsula and along the West Antarctic coast appear to be thinning significantly, with a 23 +/- 3 cm per year surface elevation decrease on the Larsen ice shelf and a 65 +/- 4 cm per year decrease on the Dotson ice shelf. On the grounded ice, significant elevation decreases are obtained over most of the drainage basins of the Pine Island and Thwaites glaciers in West Antarctica and inland of Law Dome in East Antarctica. Significant elevation increases are observed within about 200 km of the coast around much of the rest of the ice sheet. Farther inland, the changes are a mixed pattern of increases and decreases with increases of a few centimeters per year at the highest elevations of the East Antarctic plateau. The derived elevation changes are combined with estimates of the bedrock uplift from several models to provide maps of ice thickness change. The ice thickness changes enable estimates of the ice mass balances for the major drainage basins, the overall mass balance, and the current contribution of the ice sheet to global sea level change.
Duan, Honglang; O'Grady, Anthony P; Duursma, Remko A; Choat, Brendan; Huang, Guomin; Smith, Renee A; Jiang, Yanan; Tissue, David T
2015-07-01
Future climate regimes characterized by rising [CO2], rising temperatures and associated droughts may differentially affect tree growth and physiology. However, the interactive effects of these three factors are complex because elevated [CO2] and elevated temperature may generate differential physiological responses during drought. To date, the interactive effects of elevated [CO2] and elevated temperature on drought-induced tree mortality remain poorly understood in gymnosperm species that differ in stomatal regulation strategies. Water relations and carbon dynamics were examined in two species with contrasting stomatal regulation strategies: Pinus radiata D. Don (relatively isohydric gymnosperm; regulating stomata to maintain leaf water potential above critical thresholds) and Callitris rhomboidea R. Br (relatively anisohydric gymnosperm; allowing leaf water potential to decline as the soil dries), to assess response to drought as a function of [CO2] and temperature. Both species were grown in two [CO2] (C(a) (ambient, 400 μl l(-1)) and C(e) (elevated, 640 μl l(-1))) and two temperature (T(a) (ambient) and T(e) (ambient +4 °C)) treatments in a sun-lit glasshouse under well-watered conditions. Drought plants were then exposed to a progressive drought until mortality. Prior to mortality, extensive xylem cavitation occurred in both species, but significant depletion of non-structural carbohydrates was not observed in either species. Te resulted in faster mortality in P. radiata, but it did not modify the time-to-mortality in C. rhomboidea. C(e) did not delay the time-to-mortality in either species under drought or T(e) treatments. In summary, elevated temperature (+4 °C) had greater influence than elevated [CO2] (+240 μl l(-1)) on drought responses of the two studied gymnosperm species, while stomatal regulation strategies did not generally affect the relative contributions of hydraulic failure and carbohydrate depletion to mortality under severe drought. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
Airborne observed solar elevation and row direction effects on the near-IR/red ratio of cotton
NASA Technical Reports Server (NTRS)
Millard, J. P.; Jackson, R. D.; Goettelman, R. C.; Leroy, M. J. (Principal Investigator)
1981-01-01
An airborne multispectral scanner was used to obtain data over two adjacent cotton fields having rows perpendicular to one another, at three times of day (different solar elevations), and on two dates (different plant size). The near IR/red ratios were displayed in image form, so that within-field variations and differences between fields could be easily assessed. The ratio varied with changing Sun elevation for north-south oriented rows, but no variation was detected for east-west oriented rows.
Effects of nuclear radiation and elevated temperature storage on electroexplosive devices
NASA Technical Reports Server (NTRS)
Menichelli, V. J.
1976-01-01
Aerospace type electroexplosive devices (EEDs) were subjected to nuclear radiation. Components and chemicals used in the EEDs were also included. The kind of radiation and total dosage administered were those which may be experienced in a space flight of 10 years duration, based on information available at this time. After irradiation, the items were stored in elevated constant-temperature ovens to accelerate early effects of the exposure to radiation. Periodically, samples were withdrawn for visual observation and testing. Significant changes occurred which were attributed to elevated-temperature storage and not radiation.
Changes in renal function and fluid and electrolyte regulation in space flight
NASA Technical Reports Server (NTRS)
Leach, C. S.
1992-01-01
The cephalad fluid redistribution resulting from weightlessness has a number of physiologic consequences. Plasma volume is reduced soon after weightlessness is reached, and red blood cell mass reduction follows. Plasma atrial natriuretic peptide, which inhibits aldosterone secretion, was elevated during space flight while plasma aldosterone was below preflight levels. Serum sodium was also reduced and potassium was elevated. Antidiuretic hormone (ADH) was markedly elevated at almost all measurement times in the first eight days of flight, but plasma volume did not return to preflight levels.
Study for elevator cage position during the braking period
NASA Astrophysics Data System (ADS)
Ungureanu, M.; Crăciun, I.; Bănică, M.; Dăscălescu, A.
2016-08-01
An important problem in order to study an elevator cage position for its braking period is to establish a correlation between the studies in the fields of mechanics and electric. The classical approaches to establish the elevator kinematic parameters are position, velocity and acceleration, but the last studies performed in order to determine the positioning performed by introducing supplementary another parameter - the jerk- which is derived with respect to time of acceleration. Thus we get a precise method for cage motion control for third-order trajectory planning.
How much can we save? Impact of different emission scenarios on future snow cover in the Alps
NASA Astrophysics Data System (ADS)
Marty, Christoph; Schlögl, Sebastian; Bavay, Mathias; Lehning, Michael
2017-02-01
This study focuses on an assessment of the future snow depth for two larger Alpine catchments. Automatic weather station data from two diverse regions in the Swiss Alps have been used as input for the Alpine3D surface process model to compute the snow cover at a 200 m horizontal resolution for the reference period (1999-2012). Future temperature and precipitation changes have been computed from 20 downscaled GCM-RCM chains for three different emission scenarios, including one intervention scenario (2 °C target) and for three future time periods (2020-2049, 2045-2074, 2070-2099). By applying simple daily change values to measured time series of temperature and precipitation, small-scale climate scenarios have been calculated for the median estimate and extreme changes. The projections reveal a decrease in snow depth for all elevations, time periods and emission scenarios. The non-intervention scenarios demonstrate a decrease of about 50 % even for elevations above 3000 m. The most affected elevation zone for climate change is located below 1200 m, where the simulations show almost no snow towards the end of the century. Depending on the emission scenario and elevation zone the winter season starts half a month to 1 month later and ends 1 to 3 months earlier in this last scenario period. The resulting snow cover changes may be roughly equivalent to an elevation shift of 500-800 or 700-1000 m for the two non-intervention emission scenarios. At the end of the century the number of snow days may be more than halved at an elevation of around 1500 m and only 0-2 snow days are predicted in the lowlands. The results for the intervention scenario reveal no differences for the first scenario period but clearly demonstrate a stabilization thereafter, comprising much lower snow cover reductions towards the end of the century (ca. 30 % instead of 70 %).
Enhanced radiation resistant fiber optics
Lyons, Peter B.; Looney, Larry D.
1993-01-01
A process for producing an optical fiber having enhanced radiation resitance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation.
Enhanced radiation resistant fiber optics
Lyons, P.B.; Looney, L.D.
1993-11-30
A process for producing an optical fiber having enhanced radiation resistance is provided, the process including maintaining an optical fiber within a hydrogen-containing atmosphere for sufficient time to yield a hydrogen-permeated optical fiber having an elevated internal hydrogen concentration, and irradiating the hydrogen-permeated optical fiber at a time while the optical fiber has an elevated internal hydrogen concentration with a source of ionizing radiation. The radiation source is typically a cobalt-60 source and the fiber is pre-irradiated with a dose level up to about 1000 kilorads of radiation. 4 figures.
Khot, Umesh N; Johnson, Michele L; Ramsey, Curtis; Khot, Monica B; Todd, Randall; Shaikh, Saeed R; Berg, William J
2007-07-03
Consensus guidelines and hospital quality-of-care programs recommend that ST-elevation myocardial infarction patients achieve a door-to-balloon time of < or = 90 minutes. However, there are limited prospective data on specific measures to significantly reduce door-to-balloon time. We prospectively determined the impact on median door-to-balloon time of a protocol mandating (1) emergency department physician activation of the catheterization laboratory and (2) immediate transfer of the patient to an immediately available catheterization laboratory by an in-house transfer team consisting of an emergency department nurse, a critical care unit nurse, and a chest pain unit nurse. We collected door-to-balloon time for 60 consecutive ST-elevation myocardial infarction patients undergoing emergency percutaneous intervention within 24 hours of presentation from October 1, 2004, through August 31, 2005, and compared this group with 86 consecutive ST-elevation myocardial infarction patients from September 1, 2005, through June 26, 2006, after protocol implementation. Median door-to-balloon time decreased overall (113.5 versus 75.5 minutes; P<0.0001), during regular hours (83.5 versus 64.5 minutes; P=0.005), during off-hours (123.5 versus 77.5 minutes; P<0.0001), and with transfer from an outside affiliated emergency department (147 versus 85 minutes; P=0.0006). Treatment within 90 minutes increased from 28% to 71% (P<0.0001). Mean infarct size decreased (peak creatinine kinase, 2623+/-3329 versus 1517+/-1556 IU/L; P=0.0089), as did hospital length of stay (5+/-7 versus 3+/-2 days; P=0.0097) and total hospital costs per admission ($26,826+/-29,497 versus $18,280+/-8943; P=0.0125). Emergency department physician activation of the catheterization laboratory and immediate transfer of the patient to an immediately available catheterization laboratory reduce door-to-balloon time, leading to a reduction in myocardial infarct size, hospital length of stay, and total hospital costs.
Tether Impact Rate Simulation and Prediction with Orbiting Satellites
NASA Technical Reports Server (NTRS)
Harrison, Jim
2002-01-01
Space elevators and other large space structures have been studied and proposed as worthwhile by futuristic space planners for at least a couple of decades. In June 1999 the Marshall Space Flight Center sponsored a Space Elevator workshop in Huntsville, Alabama, to bring together technical experts and advanced planners to discuss the current status and to define the magnitude of the technical and programmatic problems connected with the development of these massive space systems. One obvious problem that was identified, although not for the first time, were the collision probabilities between space elevators and orbital debris. Debate and uncertainty presently exist about the extent of the threat to these large structures, one in this study as large in size as a space elevator. We have tentatively concluded that orbital debris although a major concern not sufficient justification to curtail the study and development of futuristic new millennium concepts like the space elevators.
Anderson, Dudley G.; Clark, John L.
1974-01-01
From the spring of 1971 to September 1973, neighborhood surveys were conducted in 58 communities throughout the nation to determine whether children with confirmed elevated blood lead levels could be identified. Another purpose of these screenings was to assist communities in identifying children with elevated blood lead levels and thereby demonstrate to community officials that such children do exist in communities screened. The children screened were not a random sample. In those communities where the initial elevated blood levels were confirmed all but seven had one or more children requiring followup and/or treatment. Of those children screened, black children had an elevated rate about three times as great as nonblack children. With few exceptions, the homes in the neighborhoods had at least one interior surface with sufficient quantities of lead paint to be dangerous if the paint were ingested. PMID:4831146
Thorne, Karen M.; Elliott-Fisk, Deborah L.; Wylie, Glenn D.; Perry, William M.; Takekawa, John Y.
2014-01-01
We evaluated the biogeomorphic processes of a large (309 ha) tidal salt marsh and examined factors that influence its ability to keep pace with relative sea-level rise (SLR). Detailed elevation data from 1995 and 2008 were compared with digital elevation models (DEMs) to assess marsh surface elevation change during this time. Overall, 37 % (113 ha) of the marsh increased in elevation at a rate that exceeded SLR, whereas 63 % (196 ha) of the area did not keep pace with SLR. Of the total area, 55 % (169 ha) subsided during the study period, but subsidence varied spatially across the marsh surface. To determine which biogeomorphic and spatial factors contributed to measured elevation change, we collected soil cores and determined percent and origin of organic matter (OM), particle size, bulk density (BD), and distance to nearest bay edge, levee, and channel. We then used Akaike Information Criterion (AICc) model selection to assess those variables most important to determine measured elevation change. Soil stable isotope compositions were evaluated to assess the source of the OM. The samples had limited percent OM by weight (-3, indicating that the soils had high mineral content with a relatively low proportion of pore space. The most parsimonious model with the highest AICc weight (0.53) included distance from bay's edge (i.e., lower intertidal) and distance from levee (i.e., upper intertidal). Close proximity to sediment source was the greatest factor in determining whether an area increased in elevation, whereas areas near landward levees experienced subsidence. Our study indicated that the ability of a marsh to keep pace with SLR varied across the surface, and assessing changes in elevation over time provides an alternative method to long-term accretion monitoring. SLR models that do not consider spatial variability of biogeomorphic and accretion processes may not correctly forecast marsh drowning rates, which may be especially true in modified and urbanized estuaries. In light of SLR, improving our understanding of elevation change in these dynamic marsh systems will play a crucial role in forecasting potential impacts to their sustainability and the survival of these ecosystems.
NASA Technical Reports Server (NTRS)
Shuman, Christopher A.; Sigurdsson, Oddur; Williams, Richard, Jr.; Hall, Dorothy K.
2009-01-01
Located on the Vestfirdir Northwest Fjords), DrangaJokull is the northernmost ice map in Iceland. Currently, the ice cap exceeds 900 m in elevation and covered an area of approx.l46 sq km in August 2004. It was about 204 sq km in area during 1913-1914 and so has lost mass during the 20th century. Drangajokull's size and accessibility for GPS surveys as well as the availability of repeat satellite altimetry profiles since late 2003 make it a good subject for change-detection analysis. The ice cap was surveyed by four GPS-equipped snowmobiles on 19-20 April 2005 and has been profiled in two places by Ice, Cloud. and land Elevation Satellite (ICESat) 'repeat tracks,' fifteen times from late to early 2009. In addition, traditional mass-balance measurements have been taken seasonally at a number of locations across the ice cap and they show positive net mass balances in 2004/2005 through 2006/2007. Mean elevation differences between the temporally-closest ICESat profiles and the GPS-derived digital-elevation model (DEM)(ICESat - DEM) are about 1.1 m but have standard deviations of 3 to 4 m. Differencing all ICESat repeats from the DEM shows that the overall elevation difference trend since 2003 is negative with losses of as much as 1.5 m/a from same season to same season (and similar elevation) data subsets. However, the mass balance assessments by traditional stake re-measurement methods suggest that the elevation changes where ICESat tracks 0046 and 0307 cross Drangajokull are not representative of the whole ice cap. Specifically, the area has experienced positive mass balance years during the time frame when ICESat data indicates substantial losses. This analysis suggests that ICESat-derived elevations may be used for multi-year change detection relative to other data but suggests that large uncertainties remain. These uncertainties may be due to geolocation uncertainty on steep slopes and continuing cloud cover that limits temporal and spatial coverage across the area.
Expansion of a regional ST-segment-elevation myocardial infarction system to an entire state.
Jollis, James G; Al-Khalidi, Hussein R; Monk, Lisa; Roettig, Mayme L; Garvey, J Lee; Aluko, Akinyele O; Wilson, B Hadley; Applegate, Robert J; Mears, Greg; Corbett, Claire C; Granger, Christopher B
2012-07-10
Despite national guidelines calling for timely coronary artery reperfusion, treatment is often delayed, particularly for patients requiring interhospital transfer. One hundred nineteen North Carolina hospitals developed coordinated plans to rapidly treat patients with ST-segment-elevation myocardial infarction according to presentation: walk-in, ambulance, or hospital transfer. A total of 6841 patients with ST-segment-elevation myocardial infarction (3907 directly presenting to 21 percutaneous coronary intervention hospitals, 2933 transferred from 98 non-percutaneous coronary intervention hospitals) were treated between July 2008 and December 2009 (age, 59 years; 30% women; 19% uninsured; chest pain duration, 91 minutes; shock, 9.2%). The rate of patients not receiving reperfusion fell from 5.4% to 4.0% (P=0.04). Treatment times for hospital transfer patients substantially improved. First-hospital-door-to-device time for hospitals that adopted a "transfer for percutaneous coronary intervention" reperfusion strategy fell from 117 to 103 minutes (P=0.0008), whereas times at hospitals with a mixed strategy of transfer or fibrinolysis fell from 195 to 138 minutes (P=0.002). Median door-to-device times for patients presenting directly to PCI hospitals fell from 64 to 59 minutes (P<0.001). Emergency medical services-transported patients were most likely to reach door-to-device goals, with 91% treated within 90 minutes and 52% being treated with 60 minutes. Patients treated within guideline goals had a mortality of 2.2% compared with 5.7% for those exceeding guideline recommendations (P<0.001). Through extension of regional coordination to an entire state, rapid diagnosis and treatment of ST-segment-elevation myocardial infarction has become an established standard of care independently of healthcare setting or geographic location.
Aref, Ahmad A; Scott, Ingrid U; Oden, Neal L; Ip, Michael S; Blodi, Barbara A; VanVeldhuisen, Paul C
2015-09-01
The Standard of Care vs Corticosteroid for Retinal Vein Occlusion (SCORE) Study showed that intravitreal triamcinolone acetonide (IVTA) is effective at reducing macular edema and improving visual acuity in participants with retinal vein occlusion. Secondary analysis of the incidence, risk factors, and timing of intraocular pressure (IOP) elevation occurring after IVTA provides guidance for clinical decision making and management of patients treated with IVTA. To investigate the incidence, risk factors, and time course of IOP elevation in participants in the SCORE Study. Secondary analysis conducted from August through December 2014 of a prospective, randomized clinical trial featuring an evaluable population conducted at 75 clinical sites. Six hundred eighty-two patients with macular edema secondary to retinal vein occlusion were enrolled in the study. The SCORE Study enrollment period ran from November 4, 2004, to February 29, 2008, with participant follow-up ending February 28, 2009. Study participants were randomized to standard of care, 1 mg of IVTA, or 4 mg of IVTA therapy and followed up for a mean (SD) of 24.7 (10.3) months. Intraocular pressure elevation greater than 10 mm Hg from baseline. Kaplan-Meier incidences of IOP elevation greater than 10 mm Hg from baseline at 36 months were 0.02 (95% CI, 0.01-0.06), 0.09 (95% CI, 0.05-0.14), and 0.45 (95% CI, 0.38-0.53) in the standard of care, 1-mg IVTA, and 4-mg IVTA groups, respectively. The rates of IOP-related events were higher for the 4-mg IVTA group compared with the other groups (P ≤ .001 for main outcome measure). Younger age, 4-mg IVTA vs 1-mg IVTA treatment, and higher baseline IOP were found to confer greater risk for IOP-related events (P < .05 for all). The median number of days from time of first injection to IOP elevation greater than 10 mm Hg from baseline was 34.0 and 52.5 days in participants treated with 1-mg and 4-mg IVTA, respectively. Intravitreal triamcinolone acetonide injection therapy, in particular the 4-mg dose, is associated with an increased risk for IOP elevation. The risk factors for an IOP-related event include higher treatment dose, younger age, and higher baseline IOP. Intraocular pressure-related events may take several months from the time of first IVTA injection to occur. Clinicians should be mindful of these risk factors when assessing the risks and benefits of IVTA therapy and also of the need for long-term follow-up of participants at risk for this complication. clinicaltrials.gov Identifier: NCT00105027.
Choh, Vivian; Gurdita, Akshay; Tan, Bingyao; Prasad, Ratna C.; Bizheva, Kostadinka; Joos, Karen M.
2016-01-01
Purpose Moderately elevated intraocular pressure (IOP) is a risk factor for open-angle glaucoma. Some patients suffer glaucoma despite clinically measured normal IOPs. Fluctuations in IOP may have a significant role since IOPs are higher during sleep and inversion activities. Controlled transient elevations of IOPs in rats over time lead to optic nerve structural changes that are similar to the early changes observed in constant chronic models of glaucoma. Because early intervention decreases glaucoma progression, this study was done to determine if early physiological changes to the retina could be detected with noninvasive electrophysiological and optical imaging tests during moderately elevated IOP. Methods Intraocular pressures were raised to moderately high levels (35 mm Hg) in one eye of Sprague-Dawley rats while the other (control) eye was untreated. One group of rats underwent scotopic threshold response (STR) and electroretinogram (ERG) testing, while another 3 groups underwent optical coherence tomography (OCT) imaging, Western blot, or histologic evaluation. Results The amplitudes of the STR and ERG responses in eyes with moderately elevated IOPs were enhanced compared to the values before IOP elevation, and compared to untreated contralateral eyes. Structural changes to the optic nerve also occurred during IOP elevation. Conclusions Although ischemic IOP elevations are well-known to globally reduce components of the scotopic ERG, acute elevation in rats to levels often observed in untreated glaucoma patients caused an increase in these parameters. Further exploration of these phenomena may be helpful in better understanding the mechanisms mediating early retinal changes during fluctuating or chronically elevated IOP. PMID:27100161
Nuotio, Maria S; Luukkaala, Tiina; Tammela, Teuvo
2018-04-09
Multiple factors contribute to elevated post-void residual urine volumes (PVR), but they may indicate detrusor underactivity (DU), especially in older women. The aim here was to examine factors associated with and prognostic significance of elevated PVR in a geriatric post-hip fracture assessment in a female population. Consecutive female hip fracture patients (n = 409) aged 65 years and older were included. PVR was measured by bladder scanner. PVR of 160 ml or more was deemed elevated. Age-adjusted univariate logistic regression analyses were conducted to examine the association of the domains of the comprehensive geriatric assessment (CGA) with elevated PVR. Cox proportional hazards model was used to determine the age-adjusted association of an elevated PVR with 1-year mortality. Of the patients, 64 (15.6%) had elevated PVR. Having urinary or fecal incontinence, difficulties in physical activities of daily living, malnutrition, poor performance on Timed Up and Go and Elderly Mobility Scale were significantly associated with elevated PVR. Difficulties in instrumental activities of daily living, renal dysfunction, constipation, polypharmacy, nocturia, cognitive impairment and depressive mood were not associated with elevated PVR. Elevated PVR significantly increased the risk of mortality 1 year post hip fracture. Elevated PVR is relatively common in older female hip fracture patients and associated with physical functioning, malnutrition and risk of mortality. Even though a causal relationship cannot be confirmed, the findings may suggest a relationship between DU and physical frailty. PVR deserves to be included in the CGA of frail older patients including women.
Effect of contact time and force on monocyte adhesion to vascular endothelium.
Rinker, K D; Prabhakar, V; Truskey, G A
2001-01-01
In this study we examined whether monocytic cell attachment to vascular endothelium was affected by elevating shear stress at a constant shear rate. Contact time, which is inversely related to the shear rate, was fixed and viscosity elevated with dextran to increase the shear stress (and hence the net force on the cell) independently of shear rate. At a fixed contact time, tethering frequencies increased, rolling velocities decreased, and median arrest durations increased with increasing shear stress. Rolling and short arrests (< 0.2 s) were well fit by a single exponential consistent with adhesion via the formation of a single additional bond. The cell dissociation constant, k(off), increased when the shear stress was elevated at constant shear rate. Firmly adherent cells arresting for at least 0.2 s were well fit by a stochastic model involving dissociation from multiple bonds. Therefore, at a fixed contact time and increasing shear stress, bonds formed more frequently for rolling cells resulting in more short arrests, and more bonds formed for firmly arresting cells resulting in longer arrest durations. Possible mechanisms for this increased adhesion include greater monocyte deformation and/or more frequent penetration of microvilli through steric and charge barriers. PMID:11259286
Scientific return of a lunar elevator
NASA Astrophysics Data System (ADS)
Eubanks, T. M.; Radley, C. F.
2016-11-01
The concept of a space elevator dates back to Tsilokovsky, but they are not commonly considered in near-term plans for space exploration, perhaps because a terrestrial elevator would not be possible without considerable improvements in tether material. A Lunar Space Elevator (LSE), however, can be built with current technology using commercially available tether polymers. This paper considers missions leading to infrastructure capable of shortening the time, lowering the cost and enhancing the capabilities of robotic and human explorers. These missions use planetary scale tethers, strings many thousands of kilometers long stabilized either by rotation or by gravitational gradients. These systems promise major reduction in transport costs versus chemical rockets, in a rapid timeframe, for a modest investment. Science will thus benefit as well as commercial activities.
Remotely-sensed near real-time monitoring of reservoir storage in India
NASA Astrophysics Data System (ADS)
Tiwari, A. D.; Mishra, V.
2017-12-01
Real-time reservoir storage information at a high temporal resolution is crucial to mitigate the influence of extreme events like floods and droughts. Despite large implications of near real-time reservoir monitoring in India for water resources and irrigation, remotely sensed monitoring systems have been lacking. Here we develop remotely sensed real-time monitoring systems for 91 large reservoirs in India for the period from 2000 to 2017. For the reservoir storage estimation, we combined Moderate Resolution Imaging Spectroradiometer (MODIS) 8-day 250 m Enhanced Vegetation Index (EVI), and Geoscience Laser Altimeter System (GLAS) onboard the Ice, Cloud, and land Elevation Satellite (ICESat) ICESat/GLAS elevation data. Vegetation data with the highest temporal resolution available from the MODIS is at 16 days. To increase the temporal resolution to 8 days, we developed the 8-day composite of near infrared, red, and blue band surface reflectance. Surface reflectance 8-Day L3 Global 250m only have NIR band and Red band, therefore, surface reflectance of 8-Day L3 Global at 500m is used for the blue band, which was regridded to 250m spatial resolution. An area-elevation relationship was derived using area from an unsupervised classification of MODIS image followed by an image enhancement and elevation data from ICESat/GLAS. A trial and error method was used to obtain the area-elevation relationship for those reservoirs for which ICESat/GLAS data is not available. The reservoir storages results were compared with the gauge storage data from 2002 to 2009 (training period), which were then evaluated for the period of 2010 to 2016. Our storage estimates were highly correlated with observations (R2 = 0.6 to 0.96), and the normalized root mean square error (NRMSE) ranged between 10% and 50%. We also developed a relationship between precipitation and reservoir storage that can be used for prediction of storage during the dry season.
NASA Astrophysics Data System (ADS)
Moffett, K. B.; Smith, B. C.; O'Connor, M.; Mohrig, D. C.
2014-12-01
Coastal fluvial delta morphodynamics are prominently controlled by external fluvial sediment and water supplies; however, internal sediment-water-vegetation feedbacks are now being proposed as potentially equally significant in organizing and maintaining the progradation and aggradation of such systems. The time scales of fluvial and climate influences on these feedbacks, and of their responses, are also open questions. Historical remote sensing study of the Wax Lake Delta model system (Louisiana, USA) revealed trends in the evolution of the subaerial island surfaces from a non-systematic arrangement of elevations to a discrete set of levees and intra-island platforms with distinct vegetation types, designated as high marsh, low marsh, and mudflat habitat. We propose that this elevation zonation is consistent with multiple stable state theory, e.g. as applied to tidal salt marsh systems but not previously to deltas. According to zonally-distributed sediment core analyses, differentiation of island elevations was not due to organic matter accumulation as in salt marshes, but rather by differential mineral sediment accumulation with some organic contributions. Mineral sediment accumulation rates suggested that elevation growth was accelerating or holding steady over time, at least to date in this young delta, in contrast to theory suggesting rates should slow as elevation increases above mean water level. Hydrological analysis of island flooding suggested a prominent role of stochastic local storm events in raising island water levels and supplying mineral sediment to the subaerial island surfaces at short time scales; over longer time scales, the relative influences of local storms and inland/regional floods on the coupled sediment-water-vegetation system of the subaerial delta island surfaces remain the subject of ongoing study. These results help provide an empirical foundation for the next generation of coupled sediment-water-vegetation modeling and theory.
ERIC Educational Resources Information Center
Ge, Xiaojia; Kim, Irene J.; Brody, Gene H.; Conger, Rand D.; Simons, Ronald L.; Gibbons, Frederick X.; Cutrona, Carolyn E.
2003-01-01
Examined effects of early physical maturation and accelerated pubertal changes on symptoms of major depression among 639 African American adolescents. Found that for girls, early maturation was consistently associated with elevated levels of depressive symptoms. For boys, early maturers showed elevated depression only at age 11, with symptoms…
Abstract: We investigated the effects of elevated soil temperature and atmospheric CO2 on soil CO2 efflux and system respiration responses. The study was conducted in sun-lit controlled-environment chambers using two-year-old Douglas-fir seedlings grown in reconstructed litter-so...
USDA-ARS?s Scientific Manuscript database
Global changes that alter the amount and timing of plant-available water may have profound effects on arid and semi-arid ecosystems. In addition to predicted changes in precipitation, both elevated CO2 and warming can alter water availability, often in opposite ways. Few studies, however, have measu...
A materials test system for static compression at elevated temperatures
NASA Astrophysics Data System (ADS)
Korellis, J. S.; Steinhaus, C. A.; Totten, J. J.
1992-06-01
This report documents modifications to our existing computer-controlled compression testing system to allow elevated temperature testing in an evacuated environment. We have adopted an 'inverse' design configuration where the evacuated test volume is located within the induction heating coil, eliminating the expense and minimizing the evacuation time of a much larger traditional vacuum chamber.
75 FR 2055 - Airworthiness Directives; Fokker Services B.V. Model F.28 Mark 0070 and 0100 Airplanes
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-14
... include inspecting the backlash remover of the elevator booster control unit to determine the displacement... measurement of the displacement, the compliance time for replacement ranges from before further flight to 3... of the elevator booster control unit to determine the displacement of the pivot bolt; and if...
Barbara J. Bentz; Celia Boone; Kenneth F. Raffa
2015-01-01
Mountain pine beetle (Dendroctonus ponderosae) is an important disturbance agent in Pinus ecosystems of western North America, historically causing significant tree mortality. Most recorded outbreaks have occurred in mid elevation lodgepole pine (Pinus contorta). In warm years, tree mortality also occurs at higher elevations in mixed species stands.
NASA Technical Reports Server (NTRS)
Shazly, Mostafa; Prakash, Vikas; Draper, Susan; Shukla, Arun (Editor)
2006-01-01
Recently, a new generation of titanium aluminide alloy, named Gamma-Met PX, has been developed with better rolling and post-rolling characteristics. I'revious work on this alloy has shown the material to have higher strengths at room and elevated temperatures when compared with other gamma titanium aluminides. In particular, this new alloy has shown increased ductility at elevated temperatures under both quasi-static and high strain rate uniaxial compressive loading. However, its high strain rate tensile ductility at room and elevated temperatures is limited to approx. 1%. In the present chapter, results of a study to investigate the effects of loading rate and test temperature on the dynamic fracture initiation toughness in Gamma-Met PX are presented. Modified split Hopkinson pressure bar was used along with high-speed photography to determine the crack initiation time. Three-point bend dynamic fracture experiments were conducted at impact speeds of approx. 1 m/s and tests temperatures of up-to 1200 C. The results show that thc dynamic fracture initiation toughness decreases with increasing test temperatures beyond 600 C. Furthermore, thc effect of long time high temperature air exposure on the fracture toughness was investigated. The dynamic fracture initiation toughness was found to decrease with increasing exposure time. The reasons behind this drop are analyzed and discussed.
NASA Astrophysics Data System (ADS)
Shean, D. E.; Joughin, I.; Smith, B.; Floricioiu, D.
2015-12-01
Greenland's large marine-terminating outlet glaciers have displayed marked retreat, speedup, and thinning in recent decades. Jakobshavn Isbrae, one of Greenland's largest outlet glaciers, has retreated ~15 km, accelerated ~150%, and thinned ~200 m since the early 1990s. Here, we present a comprehensive analysis of high-resolution elevation (~2-5 m/px) and velocity (~100 m/px) time series with dense temporal coverage (daily-monthly). The Jakobshavn DEM time series consists of >70 WorldView-1/2/3 stereo DEMs and >11 TanDEM-X DEMs spanning 2008-2015. Complementary point elevation data from Operation IceBridge (ATM, LVIS), pre-IceBridge ATM flights, and ICESat-1 GLAS extend the surface elevation record to 1999 and provide essential absolute control data, enabling sub-meter horizontal/vertical accuracy for gridded DEMs. Velocity data are primarily derived from TerraSAR-X/TanDEM-X image pairs with 11-day interval from 2009-2015. These elevation and velocity data capture outlet glacier evolution with unprecedented detail during the post-ICESat era. The lower trunk of Jakobshavn displays significant seasonal velocity variations, with recent rates of ~8 km/yr during winter and >17 km/yr during summer. DEM data show corresponding seasonal elevation changes of -30 to -45 m in summer and +15 to +20 m in winter, with decreasing magnitude upstream. Seasonal discharge varies from ~30-35 Gt/yr in winter to ~45-55 Gt/yr in summer, and we integrate these measurements for improved long-term mass-balance estimates. Recent interannual trends show increased discharge, velocity, and thinning (-15 to -20 m/yr), which is consistent with long-term altimetry records. The DEM time series also reveal new details about calving front and mélange evolution during the seasonal cycle. Similar time series are available for Kangerdlugssuaq and Helheim Glaciers. These observations are improving our understanding of outlet glacier dynamics, while complementing ongoing efforts to constrain estimates for ice-sheet mass balance and present/future sea level rise contributions.
Short range laser obstacle detector. [for surface vehicles using laser diode array
NASA Technical Reports Server (NTRS)
Kuriger, W. L. (Inventor)
1973-01-01
A short range obstacle detector for surface vehicles is described which utilizes an array of laser diodes. The diodes operate one at a time, with one diode for each adjacent azimuth sector. A vibrating mirror a short distance above the surface provides continuous scanning in elevation for all azimuth sectors. A diode laser is synchronized with the vibrating mirror to enable one diode laser to be fired, by pulses from a clock pulse source, a number of times during each elevation scan cycle. The time for a given pulse of light to be reflected from an obstacle and received is detected as a measure of range to the obstacle.
NASA Technical Reports Server (NTRS)
Diamante, J. M.; Englar, T. S., Jr.; Jazwinski, A. H.
1977-01-01
Estimation theory, which originated in guidance and control research, is applied to the analysis of air quality measurements and atmospheric dispersion models to provide reliable area-wide air quality estimates. A method for low dimensional modeling (in terms of the estimation state vector) of the instantaneous and time-average pollutant distributions is discussed. In particular, the fluctuating plume model of Gifford (1959) is extended to provide an expression for the instantaneous concentration due to an elevated point source. Individual models are also developed for all parameters in the instantaneous and the time-average plume equations, including the stochastic properties of the instantaneous fluctuating plume.
Hänninen, Heikki; Slaney, Michelle; Linder, Sune
2007-02-01
Ecophysiological models predicting timing of bud burst were tested with data gathered from 40-year-old Norway spruce (Picea abies (L.) Karst.) trees growing in northern Sweden in whole-tree chambers under climatic conditions predicted to prevail in 2100. Norway spruce trees, with heights between 5 and 7 m, were enclosed in individual chambers that provided a factorial combination of ambient (365 micromol mol-1) or elevated (700 micromol mol-1) atmospheric CO2 concentration, [CO2], and ambient or elevated air temperature. Temperature elevation above ambient ranged from +2.8 degrees C in summer to +5.6 degrees C in winter. Compared with control trees, elevated air temperature hastened bud burst by 2 to 3 weeks, whereas elevated [CO2] had no effect on the timing of bud burst. A simple model based on the assumption that bud rest completion takes place on a fixed calendar day predicted timing of bud burst more accurately than two more complicated models in which bud rest completion is caused by accumulated chilling. Together with some recent studies, the results suggest that, in adult trees, some additional environmental cues besides chilling are required for bud rest completion. Although it appears that these additional factors will protect trees under predicted climatic warming conditions, increased risk of frost damage associated with earlier bud burst cannot be ruled out. Inconsistent and partially anomalous results obtained in the model fitting show that, in addition to phenological data gathered under field conditions, more specific data from growth chamber and greenhouse experiments are needed for further development and testing of the models.
NASA Astrophysics Data System (ADS)
Schoettle, E.; Burbank, D. W.; Bookhagen, B.
2014-12-01
California's Sierra Madre Mountains lie at the junction of the Coast and Transverse Ranges, where they form an arcuate range crest with peak elevations of nearly 1,800 m. Near the range crest, a gently sloping paleovalley in the Southern Sierra Madre is being consumed by the headward migration of a prominent knickpoint, with an ~250-m-high headwall abutting below the gently sloped paleovalley. This paleovalley at 1400 m elevation and other low-relief, high-elevation remnants in the Sierra Madres at elevations from 800-1400 m show that the range is young enough to have regions not yet in equilibrium with the modern base level and uplift rate. Toward the western end of the Sierra Madre, the Cuyama River cuts a bedrock canyon through the range. The canyon planform describes a meandering river that has now incised ~400 m into the range. The combination of (i) high-altitude, low-relief surfaces in the Sierra Madre including the paleovalley with (ii) a meandering planform that has been incised into bedrock by a transverse river suggests (1) a low-altitude meandering proto-Cuyama river preceded significant rock uplift, and (2) the river's incision records the rock uplift of the range. Using cosmogenic nuclides to measure both the bedrock-lowering rate of the high-elevation paleovalley and the erosion rate of the steep catchment eroding into it, we can place some limits on the timing and magnitude of rock uplift in the range. By dating bedrock straths along the river canyon's walls, we can directly quantify the pace of channel incision. Together these new estimates will yield an improved reconstruction of the timing, magnitude, and rate of rock uplift of the Sierra Madre.
Elevation dynamics in a restored versus a submerging salt marsh in Long Island Sound
Anisfeld, Shimon C.; Hill, Troy D.; Cahoon, Donald R.
2016-01-01
Accelerated sea-level rise (SLR) poses the threat of salt marsh submergence, especially in marshes that are relatively low-lying. At the same time, restoration efforts are producing new low-lying marshes, many of which are thriving and avoiding submergence. To understand the causes of these different fates, we studied two Long Island Sound marshes: one that is experiencing submergence and mudflat expansion, and one that is undergoing successful restoration. We examined sedimentation using a variety of methods, each of which captures different time periods and different aspects of marsh elevation change: surface-elevation tables, marker horizons, sediment cores, and sediment traps. We also studied marsh hydrology, productivity, respiration, nutrient content, and suspended sediment. We found that, despite the expansion of mudflat in the submerging marsh, the areas that remain vegetated have been gaining elevation at roughly the rate of SLR over the last 10 years. However, this elevation gain was only possible thanks to an increase in belowground volume, which may be a temporary response to waterlogging. In addition, accretion rates in the first half of the twentieth century were much lower than current rates, so century-scale accretion in the submerging marsh was lower than SLR. In contrast, at the restored marsh, accretion rates are now averaging about 10 mm yr−1 (several times the rate of SLR), much higher than before restoration. The main cause of the different trajectories at the two marshes appeared to be the availability of suspended sediment, which was much higher in the restored marsh. We considered and rejected alternative hypotheses, including differences in tidal flooding, plant productivity, and nutrient loading. In the submerging marsh, suspended and deposited sediment had relatively high organic content, which may be a useful indicator of sediment starvation.
Abraham, Alison G; Betoko, Aisha; Fadrowski, Jeffrey J; Pierce, Christopher; Furth, Susan L; Warady, Bradley A; Muñoz, Alvaro
2017-04-01
Clinical care decisions to treat chronic kidney disease (CKD) in a growing child must often be made without the benefit of evidence from clinical trials. We used observational data from the Chronic Kidney Disease in Children cohort to estimate the effectiveness of renin-angiotensin II-aldosterone system blockade (RAAS) to delay renal replacement therapy (RRT) in children with CKD. A total of 851 participants (median age: 11 years, median glomerular filtration rate [GFR]: 52 ml/min/1.73 m 2 , median urine protein to creatinine ratio: 0.35 mg/mg) were included. RAAS use was reported at annual study visits. Both Cox proportional hazards models with time-varying RAAS exposure and Cox marginal structural models (MSM) were used to evaluate the effect of RAAS use on time to RRT. Analyses were adjusted or weighted to control for age, male sex, glomerular diagnosis, GFR, nephrotic range proteinuria, anemia, elevated blood pressure, acidosis, elevated phosphate and elevated potassium. There were 217 RRT events over a 4.1-year median follow-up. At baseline, 472 children (55 %) were prevalent RAAS users, who were more likely to be older, have a glomerular etiology, have higher urine protein, be anemic, have elevated serum phosphate and potassium, take more medications, but less likely to have elevated blood pressure, compared with non-users. RAAS use was found to reduce the risk of RRT by 21 % (hazard ratio: 0.79) to 37 % (hazard ratio: 0.63) from standard regression adjustment and MSM models, respectively. These results support inferences from adult studies of a substantial benefit of RAAS use in pediatric CKD patients.
Geographic divergence in upper thermal limits across insect life stages: does behavior matter?
MacLean, Heidi J; Higgins, Jessica K; Buckley, Lauren B; Kingsolver, Joel G
2016-05-01
Insects with complex life cycles vary in size, mobility, and thermal ecology across life stages. We examine how differences in the capacity for thermoregulatory behavior influence geographic differences in physiological heat tolerance among egg and adult Colias butterflies. Colias adults exhibit differences in morphology (wing melanin and thoracic setal length) along spatial gradients, whereas eggs are morphologically indistinguishable. Here we compare Colias eriphyle eggs and adults from two elevations and Colias meadii from a high elevation. Hatching success and egg development time of C. eriphyle eggs did not differ significantly with the elevation of origin. Egg survival declined in response to heat-shock temperatures above 38-40 °C and egg development time was shortest at intermediate heat-shock temperatures of 33-38 °C. Laboratory experiments with adults showed survival in response to heat shock was significantly greater for Colias from higher than from lower elevation sites. Common-garden experiments at the low-elevation field site showed that C. meadii adults initiated heat-avoidance and over-heating behaviors significantly earlier in the day than C. eriphyle. Our study demonstrates the importance of examining thermal tolerances across life stages. Our findings are inconsistent with the hypothesis that thermoregulatory behavior inhibits the geographic divergence of physiological traits in mobile stages, and suggest that sessile stages may evolve similar heat tolerances in different environments due to microclimatic variability or evolutionary constraints.
Real-Time Prediction of Temperature Elevation During Robotic Bone Drilling Using the Torque Signal.
Feldmann, Arne; Gavaghan, Kate; Stebinger, Manuel; Williamson, Tom; Weber, Stefan; Zysset, Philippe
2017-09-01
Bone drilling is a surgical procedure commonly required in many surgical fields, particularly orthopedics, dentistry and head and neck surgeries. While the long-term effects of thermal bone necrosis are unknown, the thermal damage to nerves in spinal or otolaryngological surgeries might lead to partial paralysis. Previous models to predict the temperature elevation have been suggested, but were not validated or have the disadvantages of computation time and complexity which does not allow real time predictions. Within this study, an analytical temperature prediction model is proposed which uses the torque signal of the drilling process to model the heat production of the drill bit. A simple Green's disk source function is used to solve the three dimensional heat equation along the drilling axis. Additionally, an extensive experimental study was carried out to validate the model. A custom CNC-setup with a load cell and a thermal camera was used to measure the axial drilling torque and force as well as temperature elevations. Bones with different sets of bone volume fraction were drilled with two drill bits ([Formula: see text]1.8 mm and [Formula: see text]2.5 mm) and repeated eight times. The model was calibrated with 5 of 40 measurements and successfully validated with the rest of the data ([Formula: see text]C). It was also found that the temperature elevation can be predicted using only the torque signal of the drilling process. In the future, the model could be used to monitor and control the drilling process of surgeries close to vulnerable structures.
Generation of real-time mode high-resolution water vapor fields from GPS observations
NASA Astrophysics Data System (ADS)
Yu, Chen; Penna, Nigel T.; Li, Zhenhong
2017-02-01
Pointwise GPS measurements of tropospheric zenith total delay can be interpolated to provide high-resolution water vapor maps which may be used for correcting synthetic aperture radar images, for numeral weather prediction, and for correcting Network Real-time Kinematic GPS observations. Several previous studies have addressed the importance of the elevation dependency of water vapor, but it is often a challenge to separate elevation-dependent tropospheric delays from turbulent components. In this paper, we present an iterative tropospheric decomposition interpolation model that decouples the elevation and turbulent tropospheric delay components. For a 150 km × 150 km California study region, we estimate real-time mode zenith total delays at 41 GPS stations over 1 year by using the precise point positioning technique and demonstrate that the decoupled interpolation model generates improved high-resolution tropospheric delay maps compared with previous tropospheric turbulence- and elevation-dependent models. Cross validation of the GPS zenith total delays yields an RMS error of 4.6 mm with the decoupled interpolation model, compared with 8.4 mm with the previous model. On converting the GPS zenith wet delays to precipitable water vapor and interpolating to 1 km grid cells across the region, validations with the Moderate Resolution Imaging Spectroradiometer near-IR water vapor product show 1.7 mm RMS differences by using the decoupled model, compared with 2.0 mm for the previous interpolation model. Such results are obtained without differencing the tropospheric delays or water vapor estimates in time or space, while the errors are similar over flat and mountainous terrains, as well as for both inland and coastal areas.
Simulations of snow distribution and hydrology in a mountain basin
Hartman, Melannie D.; Baron, Jill S.; Lammers, Richard B.; Cline, Donald W.; Band, Larry E.; Liston, Glen E.; Tague, Christina L.
1999-01-01
We applied a version of the Regional Hydro-Ecologic Simulation System (RHESSys) that implements snow redistribution, elevation partitioning, and wind-driven sublimation to Loch Vale Watershed (LVWS), an alpine-subalpine Rocky Mountain catchment where snow accumulation and ablation dominate the hydrologic cycle. We compared simulated discharge to measured discharge and the simulated snow distribution to photogrammetrically rectified aerial (remotely sensed) images. Snow redistribution was governed by a topographic similarity index. We subdivided each hillslope into elevation bands that had homogeneous climate extrapolated from observed climate. We created a distributed wind speed field that was used in conjunction with daily measured wind speeds to estimate sublimation. Modeling snow redistribution was critical to estimating the timing and magnitude of discharge. Incorporating elevation partitioning improved estimated timing of discharge but did not improve patterns of snow cover since wind was the dominant controller of areal snow patterns. Simulating wind-driven sublimation was necessary to predict moisture losses.
Asquith, William H.; Vrabel, Joseph; Roussel, Meghan C.
2007-01-01
The U.S. Geological Survey (USGS), in cooperation with numerous Federal, State, municipal, and local agencies, currently (2007) collects data for more than 120 lakes and reservoirs in Texas through a realtime, data-collection network. The National Water Information System that processes and archives water-resources data for the Nation provides a central source for retrieval of real-time as well as historical data. This report provides a brief description of the real-time, data-collection network and graphically summarizes the period-of-record daily mean water-surface elevations for 116 active and discontinued USGS lake and reservoir stations in Texas. The report also graphically depicts selected statistics (minimum, maximum, and mean) of daily mean water-surface-elevation data. The data for water year 2006 are compared to the selected statistics.
Traffic congestion and blood pressure elevation: A comparative cross-sectional study in Lebanon.
Bou Samra, Patrick; El Tomb, Paul; Hosni, Mohammad; Kassem, Ahmad; Rizk, Robin; Shayya, Sami; Assaad, Sarah
2017-12-01
This comparative cross-sectional study examines the association between traffic congestion and elevation of systolic and/or diastolic blood pressure levels among a convenience sample of 310 drivers. Data collection took place during a gas station pause at a fixed time of day. Higher average systolic (142 vs 123 mm Hg) and diastolic (87 vs 78 mm Hg) blood pressures were detected among drivers exposed to traffic congestion compared with those who were not exposed (P<.001), while controlling for body mass index, age, sex, pack-year smoking, driving hours per week, and occupational driving. Moreover, among persons exposed to traffic congestion, longer exposure time was associated with higher systolic and diastolic blood pressures. Further studies are needed to better understand the mechanisms of the significant association between elevated blood pressure and traffic congestion. ©2017 Wiley Periodicals, Inc.
Low elevation angle KU-band satellite measurements at Austin, Texas
NASA Technical Reports Server (NTRS)
Vogel, Wolfhard J.; Torrence, Geoffrey W.; Ranganathan, Murali
1989-01-01
At low elevation angles, the propagation of satellite signals is affected by precipitation as well as by inhomogeneties of the refractive index. Whereas precipitation causes fades for relatively small percentages of time, the refractive index variability causes scintillations which can be observed for most of the time. An experiment is now under way in Austin, Texas, in which the right hand circularly polarized 12 GHz beacon of INTELSAT-V/F10 is observed at a 5.8 deg elevation angle, along with the radiometric sky temperature, rainfall rate, humidity, pressure, temperature, and wind speed and direction. The objective of these measurements is to accumulate a database over a period of 2 years and to analyze the probabilities and dynamical behavior of the signal variations in relation to the meteorological parameters. The hardware and software used for the data acquisition and analysis is described and the results from the first year of measurements are presented.
Implications of High Temperature and Elevated CO2 on Flowering Time in Plants
Jagadish, S. V. Krishna; Bahuguna, Rajeev N.; Djanaguiraman, Maduraimuthu; Gamuyao, Rico; Prasad, P. V. Vara; Craufurd, Peter Q.
2016-01-01
Flowering is a crucial determinant for plant reproductive success and seed-set. Increasing temperature and elevated carbon-dioxide (e[CO2]) are key climate change factors that could affect plant fitness and flowering related events. Addressing the effect of these environmental factors on flowering events such as time of day of anthesis (TOA) and flowering time (duration from germination till flowering) is critical to understand the adaptation of plants/crops to changing climate and is the major aim of this review. Increasing ambient temperature is the major climatic factor that advances flowering time in crops and other plants, with a modest effect of e[CO2].Integrated environmental stimuli such as photoperiod, temperature and e[CO2] regulating flowering time is discussed. The critical role of plant tissue temperature influencing TOA is highlighted and crop models need to substitute ambient air temperature with canopy or floral tissue temperature to improve predictions. A complex signaling network of flowering regulation with change in ambient temperature involving different transcription factors (PIF4, PIF5), flowering suppressors (HvODDSOC2, SVP, FLC) and autonomous pathway (FCA, FVE) genes, mainly from Arabidopsis, provides a promising avenue to improve our understanding of the dynamics of flowering time under changing climate. Elevated CO2 mediated changes in tissue sugar status and a direct [CO2]-driven regulatory pathway involving a key flowering gene, MOTHER OF FT AND TFL1 (MFT), are emerging evidence for the role of e[CO2] in flowering time regulation. PMID:27446143
Analysis of Suspended-Sediment Dynamics in Gulf of Mexico Estuaries Using MODIS/Terra 250-m Imagery
NASA Astrophysics Data System (ADS)
McCarthy, M. J.; Otis, D. B.; Muller-Karger, F. E.; Mendez-Lazaro, P.; Chen, F. R.
2016-02-01
Suspended sediments in coastal ecosystems reduce light penetration, degrade water quality, and inhibit primary production. In this study, a 15-year Moderate Resolution Imaging Spectroradiometer (MODIS/Terra) turbidity time-series was developed for use in the estuaries of the Gulf of Mexico (GOM). Remote-sensing reflectance (Rrs) at 645 nm and 250-m resolution was validated with in-situ turbidity measurements in these estuaries: Coastal Bend Bays (TX), Galveston Bay (TX), Barataria and Terrebonne Bays (LA), Mobile Bay (AL), Tampa Bay (FL), Sarasota Bay (FL), and Charlotte Harbor (FL). Mean values of turbidity over the time-series ranged from 2.5 NTU to over 10 NTU. Turbidity patterns exhibited seasonal cycles with peak values generally found during spring months, although there is considerable variability in the timing of peak turbidity. Episodes of elevated turbidity ranged from 6 episodes in Galveston Bay to 15 in Mobile Bay. The spatial extent of elevated turbidity within estuaries, frequency and duration of turbidity events, and potential driving factors behind episodes of elevated turbidity were also examined.
Zhang, Changxing; Qu, Zhe; Fang, Xufei; Feng, Xue; Hwang, Keh-Chih
2015-02-01
Thin film stresses in thin film/substrate systems at elevated temperatures affect the reliability and safety of such structures in microelectronic devices. The stresses result from the thermal mismatch strain between the film and substrate. The reflection mode digital gradient sensing (DGS) method, a real-time, full-field optical technique, measures deformations of reflective surface topographies. In this paper, we developed this method to measure topographies and thin film stresses of thin film/substrate systems at elevated temperatures. We calibrated and compensated for the air convection at elevated temperatures, which is a serious problem for optical techniques. We covered the principles for surface topography measurements by the reflection mode DGS method at elevated temperatures and the governing equations to remove the air convection effects. The proposed method is applied to successfully measure the full-field topography and deformation of a NiTi thin film on a silicon substrate at elevated temperatures. The evolution of thin film stresses obtained by extending Stoney's formula implies the "nonuniform" effect the experimental results have shown.
Hanna-Attisha, Mona; LaChance, Jenny; Sadler, Richard Casey; Champney Schnepp, Allison
2016-02-01
We analyzed differences in pediatric elevated blood lead level incidence before and after Flint, Michigan, introduced a more corrosive water source into an aging water system without adequate corrosion control. We reviewed blood lead levels for children younger than 5 years before (2013) and after (2015) water source change in Greater Flint, Michigan. We assessed the percentage of elevated blood lead levels in both time periods, and identified geographical locations through spatial analysis. Incidence of elevated blood lead levels increased from 2.4% to 4.9% (P < .05) after water source change, and neighborhoods with the highest water lead levels experienced a 6.6% increase. No significant change was seen outside the city. Geospatial analysis identified disadvantaged neighborhoods as having the greatest elevated blood lead level increases and informed response prioritization during the now-declared public health emergency. The percentage of children with elevated blood lead levels increased after water source change, particularly in socioeconomically disadvantaged neighborhoods. Water is a growing source of childhood lead exposure because of aging infrastructure.
LaChance, Jenny; Sadler, Richard Casey; Champney Schnepp, Allison
2016-01-01
Objectives. We analyzed differences in pediatric elevated blood lead level incidence before and after Flint, Michigan, introduced a more corrosive water source into an aging water system without adequate corrosion control. Methods. We reviewed blood lead levels for children younger than 5 years before (2013) and after (2015) water source change in Greater Flint, Michigan. We assessed the percentage of elevated blood lead levels in both time periods, and identified geographical locations through spatial analysis. Results. Incidence of elevated blood lead levels increased from 2.4% to 4.9% (P < .05) after water source change, and neighborhoods with the highest water lead levels experienced a 6.6% increase. No significant change was seen outside the city. Geospatial analysis identified disadvantaged neighborhoods as having the greatest elevated blood lead level increases and informed response prioritization during the now-declared public health emergency. Conclusions. The percentage of children with elevated blood lead levels increased after water source change, particularly in socioeconomically disadvantaged neighborhoods. Water is a growing source of childhood lead exposure because of aging infrastructure. PMID:26691115
Murata, Teruasa; Honda, Tetsuya; Egawa, Gyohei; Yamamoto, Yasuo; Ichijo, Ryo; Toyoshima, Fumiko; Dainichi, Teruki; Kabashima, Kenji
2018-04-26
Epidermal keratinocytes achieve sequential differentiation from basal to granular layers, and undergo a specific programmed cell death, cornification, to form an indispensable barrier of the body. Although elevation of the cytoplasmic calcium ion concentration ([Ca 2+ ] i ) is one of the factors predicted to regulate cornification, the dynamics of [Ca 2+ ] i in epidermal keratinocytes is largely unknown. Here using intravital imaging, we captured the dynamics of [Ca 2+ ] i in mouse skin. [Ca 2+ ] i was elevated in basal cells on the second time scale in three spatiotemporally distinct patterns. The transient elevation of [Ca 2+ ] i also occurred at the most apical granular layer at a single cell level, and lasted for approximately 40 min. The transient elevation of [Ca 2+ ] i at the granular layer was followed by cornification, which was completed within 10 min. This study demonstrates the tightly regulated elevation of [Ca 2+ ] i preceding the cornification of epidermal keratinocytes, providing possible clues to the mechanisms of cornification.
Brusca, Richard C; Wiens, John F; Meyer, Wallace M; Eble, Jeff; Franklin, Kim; Overpeck, Jonathan T; Moore, Wendy
2013-01-01
Models analyzing how Southwestern plant communities will respond to climate change predict that increases in temperature will lead to upward elevational shifts of montane species. We tested this hypothesis by reexamining Robert Whittaker's 1963 plant transect in the Santa Catalina Mountains of southern Arizona, finding that this process is already well underway. Our survey, five decades after Whittaker's, reveals large changes in the elevational ranges of common montane plants, while mean annual rainfall has decreased over the past 20 years, and mean annual temperatures increased 0.25°C/decade from 1949 to 2011 in the Tucson Basin. Although elevational changes in species are individualistic, significant overall upward movement of the lower elevation boundaries, and elevational range contractions, have occurred. This is the first documentation of significant upward shifts of lower elevation range boundaries in Southwestern montane plant species over decadal time, confirming that previous hypotheses are correct in their prediction that mountain communities in the Southwest will be strongly impacted by warming, and that the Southwest is already experiencing a rapid vegetation change. PMID:24223270
NASA Astrophysics Data System (ADS)
Meier, G.; Brown, J. F.; Vogelmann, J. E.; Evelsizer, R.
2012-12-01
Trembling aspen (Populus tremuloides, referred hereafter as Aspen) has an especially wide geographical distribution in North America, extending from Alaska across the Canadian provinces, the U.S., and south into Mexico. This deciduous species is successional, shade intolerant, and often exists as a dominant among other species at mid-elevations. Aspen occupies wide latitudinal, elevational, and environmental gradients making it a favorable candidate for a study of phenology and climate relationships. The phenological characterization in our Aspen study is derived from a database of conterminous U.S. phenological indicators hosted by the U.S. Geological Survey (http://phenology.cr.usgs.gov/index.php). Nine satellite-derived phenological indicators are calculated from 250m resolution Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI). From this database, we selected start of season (SOST), end of season (EOST), maximum NDVI (MaxN) and time integrated NDVI (TIN) to characterize and analyze the seasonal patterns of Aspen over a 10-year time period (2001-2010). Areas of continuous Aspen cover (≥ 80% Aspen cover type) derived from the LANDFIRE project were then used to extract elevation, precipitation, temperature, and snow water equivalent data. In the Rocky Mountains, Aspen recently suffered from multi-year drought stress accompanied by insect and disease infestations. Numerous studies have documented the existence of Sudden Aspen Decline (SAD) in Montana, Utah, Arizona, and Colorado, indicating that Aspen may be on the edge of its environmental tolerances in some areas. The satellite-derived phenology metrics, and climate and biogeographical indicators were the basis for characterizing Aspen seasonality and assessing the environmental context of SAD. Between several Aspen study areas, there was reasonably consistent progression in the SOST timing from low elevations to higher elevations. A less obvious progression was observed in the EOST, and year-to-year EOST variability appeared to be related to the timing of episodic widespread snow events. Also, higher and lower elevation Aspen stands showed lower TIN (a proxy for annual net primary productivity) and lower MaxN (a proxy for maximum vegetation vigor) compared with the mid-elevations. In the 10-year MODIS record, there was a slight trend toward a later SOST (delay from 8 to 16 days depending on the locale), but a concurrent increase of approximately 4% in the TIN over the same 10-year period. A severe drought (affecting much of Colorado) in 2002 resulted in a low TIN and very low MaxN for that year. This drought event resulted in a compression of the Aspen SOST over its full elevational range, such that Aspen showed anomalous synchronicity in phenological response apparently due to moisture stress. The occurrence of the severe drought in 2002, followed by additional dry years in 2003 and 2004 are thought to be causal factors in the occurrence of SAD. The preliminary analysis of the phenology and climate of Aspen showed the complexity of these relationships and their variability through time. Further research is proceeding to compare and contrast SAD-affected and non-SAD affected areas.
Development of a new morphometric to assess beach storm response and recovery
NASA Astrophysics Data System (ADS)
Brenner, O.; Hapke, C. J.
2014-12-01
Various morphometrics are used to measure coastal change over a variety of time scales including shoreline, dune elevation and position, and beach profile volume. Each has limitations, many of which became apparent in the aftermath of Hurricane Sandy, including the juxtaposition of levelled dunes and a substantially prograded shoreline. In order to understand sustained beach behavior, including recovery after Hurricane Sandy, we develop a new morphometric - an upper beach change envelope (BCE) specific to Fire Island, NY. The upper beach better captures impacts from more frequent moderate storms during which there may be substantial beach change but less impact to the dune, and is less subject to the variable fluctuations nearer to the shoreline that only marginally influence future vulnerability and overall coastal resilience. The BCE can also be used to quantify the gradual recovery of the beach after storm events and is not reliant on the presence of a morphologic feature such as a dune, which may take many years to recover after a severe storm.The BCE at Fire Island is based on a time series of historical response to storms. The BCE boundaries are elevation contours that capture the portion of the upper beach that experiences erosion during moderate nor'easter events but is above the influence of tides and lesser events. In an application of the BCE concept, we use the BCE boundary elevations to quantify beach response from Hurricane Sandy and document the subsequent recovery, using a time series of post-Sandy elevation contours. The data include 10 profile sites from Fire Island that were surveyed multiple times from October 2012 to June 2014. Utilizing this time series we measure changes in the cross shore position of the BCE elevation boundaries. Initial assessments indicate the BCE successfully captures coastal response through time, including extensive change during Hurricane Sandy as well as subsequent seasonal changes. The recent data indicate there is a temporal trend towards widening of the BCE, due to sustained progradation of the lower boundary. This trend may represent a new "recovery state" of the beach which is wider than the pre-Sandy beach, providing an increase in the fetch that favors the aeolian processes of dune reformation.
Changes in the timing of snowmelt and streamflow in Colorado: A response to recent warming
Clow, David W.
2010-01-01
Trends in the timing of snowmelt and associated runoff in Colorado were evaluated for the 1978-2007 water years using the regional Kendall test (RKT) on daily snow-water equivalent (SWE) data from snowpack telemetry (SNOTEL) sites and daily streamflow data from headwater streams. The RKT is a robust, nonparametric test that provides an increased power of trend detection by grouping data from multiple sites within a given geographic region. The RKT analyses indicated strong, pervasive trends in snowmelt and streamflow timing, which have shifted toward earlier in the year by a median of 2-3 weeks over the 29-yr study period. In contrast, relatively few statistically significant trends were detected using simple linear regression. RKT analyses also indicated that November-May air temperatures increased by a median of 0.9 degrees C decade-1, while 1 April SWE and maximum SWE declined by a median of 4.1 and 3.6 cm decade-1, respectively. Multiple linear regression models were created, using monthly air temperatures, snowfall, latitude, and elevation as explanatory variables to identify major controlling factors on snowmelt timing. The models accounted for 45% of the variance in snowmelt onset, and 78% of the variance in the snowmelt center of mass (when half the snowpack had melted). Variations in springtime air temperature and SWE explained most of the interannual variability in snowmelt timing. Regression coefficients for air temperature were negative, indicating that warm temperatures promote early melt. Regression coefficients for SWE, latitude, and elevation were positive, indicating that abundant snowfall tends to delay snowmelt, and snowmelt tends to occur later at northern latitudes and high elevations. Results from this study indicate that even the mountains of Colorado, with their high elevations and cold snowpacks, are experiencing substantial shifts in the timing of snowmelt and snowmelt runoff toward earlier in the year.
NASA Astrophysics Data System (ADS)
Csatho, B. M.; Schenk, A. F.; Babonis, G. S.; van den Broeke, M. R.; Kuipers Munneke, P.; van der Veen, C. J.; Khan, S. A.; Porter, D. F.
2016-12-01
This study presents a new, comprehensive reconstruction of Greenland Ice Sheet elevation changes, generated using the Surface Elevation And Change detection (SERAC) approach. 35-year long elevation-change time series (1980-2015) were obtained at more than 150,000 locations from observations acquired by NASA's airborne and spaceborne laser altimeters (ATM, LVIS, ICESat), PROMICE laser altimetry data (2007-2011) and a DEM covering the ice sheet margin derived from stereo aerial photographs (1970s-80s). After removing the effect of Glacial Isostatic Adjustment (GIA) and the elastic crustal response to changes in ice loading, the time series were partitioned into changes due to surface processes and ice dynamics and then converted into mass change histories. Using gridded products, we examined ice sheet elevation, and mass change patterns, and compared them with other estimates at different scales from individual outlet glaciers through large drainage basins, on to the entire ice sheet. Both the SERAC time series and the grids derived from these time series revealed significant spatial and temporal variations of dynamic mass loss and widespread intermittent thinning, indicating the complexity of ice sheet response to climate forcing. To investigate the regional and local controls of ice dynamics, we examined thickness change time series near outlet glacier grounding lines. Changes on most outlet glaciers were consistent with one or more episodes of dynamic thinning that propagates upstream from the glacier terminus. The spatial pattern of the onset, duration, and termination of these dynamic thinning events suggest a regional control, such as warming ocean and air temperatures. However, the intricate spatiotemporal pattern of dynamic thickness change suggests that, regardless of the forcing responsible for initial glacier acceleration and thinning, the response of individual glaciers is modulated by local conditions. We use statistical methods, such as principal component analysis and multivariate regression to analyze the dynamic ice-thickness change time series derived by SERAC and to investigate the primary forcings and controls on outlet glacier changes.
Zheng, Yinggan; Bainey, Kevin R; Tyrrell, Benjamin D; Brass, Neil; Armstrong, Paul W; Welsh, Robert C
2017-11-01
Using a comprehensive ST-segment-elevation myocardial infarction registry, we evaluated the relationships of baseline Q waves, time from symptom onset, and reperfusion strategy with in-hospital clinical outcomes. Consecutive ST-segment-elevation myocardial infarction patients from a defined health region were classified by the presence of baseline Q waves and additionally into primary percutaneous coronary intervention, fibrinolysis, or no reperfusion. ECGs were collected at baseline, after reperfusion, and analyzed for the presence of Q waves using Selvester criteria. Among 2290 ST-segment-elevation myocardial infarction patients, 36.9% had Q waves on their baseline ECG. Patients with Q waves were older (median age, 59 versus 57), were more often male (82.0% versus 75.4%), had higher heart rate (80 versus 72), had higher Global Registry of Acute Coronary Events risk score (129 versus 127), and were with longer time to reperfusion (42 minutes longer). They had higher composite end points (16.3% versus 10.0%), consistent across times from symptom onset to presentation (15.4% versus 9.9% ≤3 hours; 18.5% versus 8.9% >3 to ≤6 hours; 15.9% versus 11.3% >6 hours; Q and no Q, respectively). Baseline Q waves, but not time to reperfusion, were associated with an increased odds of the in-hospital composite end point of death, congestive heart failure, cardiogenic shock, and reinfarction (adjusted odds ratio, 1.65; 95% confidence interval, 1.18-2.30; P =0.003). Type of reperfusion did not modify the association of baseline Q waves and in-hospital outcomes ( P interaction=0.918). The presence of baseline Q waves, rather than time to treatment, was significantly associated with adverse in-hospital events in real-world patients, regardless of reperfusion strategy used. © 2017 American Heart Association, Inc.
Oron, Anna; Szymaszek, Aneta; Szelag, Elzbieta
2015-01-01
Temporal information processing (TIP) underlies many aspects of cognitive functions like language, motor control, learning, memory, attention, etc. Millisecond timing may be assessed by sequencing abilities, e.g. the perception of event order. It may be measured with auditory temporal-order-threshold (TOT), i.e. a minimum time gap separating two successive stimuli necessary for a subject to report their temporal order correctly, thus the relation 'before-after'. Neuropsychological evidence has indicated elevated TOT values (corresponding to deteriorated time perception) in different clinical groups, such as aphasic patients, dyslexic subjects or children with specific language impairment. To test relationships between elevated TOT and declined cognitive functions in brain-injured patients suffering from post-stroke aphasia. We tested 30 aphasic patients (13 male, 17 female), aged between 50 and 81 years. TIP comprised assessment of TOT. Auditory comprehension was assessed with the selected language tests, i.e. Token Test, Phoneme Discrimination Test (PDT) and Voice-Onset-Time Test (VOT), while two aspects of attentional resources (i.e. alertness and vigilance) were measured using the Test of Attentional Performance (TAP) battery. Significant correlations were indicated between elevated values of TOT and deteriorated performance on all applied language tests. Moreover, significant correlations were evidenced between elevated TOT and alertness. Finally, positive correlations were found between particular language tests, i.e. (1) Token Test and PDT; (2) Token Test and VOT Test; and (3) PDT and VOT Test, as well as between PDT and both attentional tasks. These results provide further clinical evidence supporting the thesis that TIP constitutes the core process incorporated in both language and attentional resources. The novel value of the present study is the indication for the first time in Slavic language users a clear coexistence of the 'timing-auditory comprehension-attention' relationships. © 2015 Royal College of Speech and Language Therapists.
Effects of free-air CO2 and temperature enrichment on soybean growth and development
NASA Astrophysics Data System (ADS)
Ruiz Vera, U. M.; Bernacchi, C. J.
2012-12-01
According to the growing degree days approach, the progression of plant developmental stages requires certain accumulation of heat; therefore greenhouse gas-induced warming of the atmosphere could contribute to more rapid plant development. However, the influence of rising carbon dioxide concentration ([CO2]) on development of crops is uncertain, accelerating and other times delaying certain developmental stages. In soybean, the increase of [CO2] is shown to delay reproductive development, which is attributed to a higher investment of resources into extra nodes. The combined effects of elevated temperature and [CO2] can have significant changes in the progression through development that can influence on total grain production, carbon uptake, and susceptibility to early end-of-season frosts. We designed the Temperature by Free Air CO2 Enrichment (T-FACE) experiment to test over two growing seasons (2009 and 2011) and under field conditions the impact of increased temperature and/or [CO2] on soybean. The heated T-FACE subplots were situated in the larger FACE plots at 385 or 585 ppm of [CO2] and subjected to either ambient or heated (+~3.5°C) temperatures. The experiment is full factorial with ambient temperature and [CO2] (control), elevated temperature (eT), elevated [CO2] (eC) and combined (eT+eC) treatments. We hypothesized that soybean grown (1) under elevated [CO2] will produce more nodes than control, (2) under high temperature will produce nodes faster than control and (3) under both elevated temperature and [CO2] will produce more nodes in less time than control. For reproductive development, we hypothesized that (1) reproductive development will initiate simultaneously regardless of increased [CO2] or temperature because soybean reproduction is triggered by day length, (2) elevated temperature will accelerate the progression through key reproductive stages and (3) the delay in soybean reproductive development by elevated [CO2] will be ameliorated by the raise in temperature. Soybean developmental stages were recorded on six plants per subplot three times per week from emergence to senescence. In 2009, no temperature effect was detected on the vegetative development, but in 2011 temperature accelerates node formation. Elevated [CO2] was not significant on vegetative development, however plants under this effect produced more nodes than control. Reproductive development was delayed by elevated [CO2]. High temperature accelerated reproductive stages only in 2009, ameliorating the effect of elevated [CO2] in eT+eC. In 2011 elevated temperature delayed reproductive stages, a response that could be related with stress imposed by the weather conditions of that season. In the Midwest, the soybean cultivars generally mature before the first frost of the year avoiding seed damage. The delayed in soybean maturation by the increasing of [CO2] could potentially reduce yield; however the increase of temperature could diminish this risk by mitigating this delay. Alternatively, the more rapid progression through the reproductive stages could decrease the translocation of resources to pods, thereby negatively impacting yields. Using soybean as a model for leguminous C3 species suggested implications could arise for yield in crop plants and reproductive fitness in native vegetation.
Williams, Kelly K; McMillin, Joel D; DeGomez, Tom E; Clancy, Karen M; Miller, Andy
2008-02-01
We examined abundance and flight periodicity of five Ips and six Dendroctonus species (Coleoptera: Curculionidae, Scolytinae) among three different elevation bands in ponderosa pine (Pinus ponderosa Douglas ex. Lawson) forests of northcentral Arizona. Bark beetle populations were monitored at 10 sites in each of three elevation bands (low: 1,600-1,736 m; middle: 2,058-2,230 m; high: 2,505-2,651 m) for 3 yr (2004-2006) using pheromone-baited Lindgren funnel traps. Trap contents were collected weekly from March to December. We also studied temperature differences among the elevation bands and what role this may play in beetle flight behavior. Bark beetles, regardless of species, showed no consistent elevational trend in abundance among the three bands. The higher abundances of Ips lecontei Swaine, I. calligraphus ponderosae Swaine, Dendroctonus frontalis Zimmerman, and D. brevicomis LeConte at low and middle elevations offset the greater abundance of I. knausi Swaine, D. adjunctus Blandford, D. approximatus Dietz, and D. valens LeConte at high elevations. I. pini (Say) and I. latidens LeConte were found in similar numbers across the three bands. Flight periodicity of several species varied among elevation bands. In general, the flight period shortened as elevation increased; flight initiated later and terminated earlier in the year. The timing, number, and magnitude of peaks in flight activity also varied among the elevation bands. These results suggest that abundance and flight seasonality of several bark beetles are related to elevation and the associated temperature differences. The implications of these results are discussed in relation to bark beetle management and population dynamics.
The role of elevated serum procalcitonin in neuroendocrine neoplasms of digestive system.
Chen, Luohai; Zhang, Yu; Lin, Yuan; Deng, Langhui; Feng, Shiting; Chen, Minhu; Chen, Jie
2017-12-01
Elevated serum procalcitonin (PCT) was reported in patients with certain type of neuroendocrine neoplasms (NENs). The aim of this study was to assess the role of elevated serum PCT in NENs from digestive system. Serum PCT and serum CgA level were measured in 155 patients with NENs from digestive system. Elevated serum PCT was found in 63 patients (40.6%). Grade 3 disease was a significant factor associated with elevated serum PCT (OR, 9.24; 95%CI, 3.04-28.08; P<0.001). Serum PCT level was significantly decreased after treatment both in patients with stable disease (P=0.003) and patients with partial remission (P=0.001). In these patients, serum PCT level significantly increased again at the time of progression disease (P=0.001). Elevated serum PCT was a significant factor of worse survival (HR, 2.86; 95%CI, 1.36-6.03; P=0.006). Compared with patients with normal serum PCT and CgA level, patients with either PCT or CgA elevated and patients with both PCT and CgA elevated had progressively worse survival. Additionally, PCT expression in tumor cells was found in 24.0% of patients but did not correlate with other clinicopathological factors, including serum PCT. Serum PCT is elevated in part of patients with NENs of digestive system, especially in patients with grade 3 disease. Serum PCT level can help evaluate treatment response and its elevation indicates poor prognosis. Combination of serum PCT and CgA can improve outcome prediction. Copyright © 2017 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Bevington, Azure E.; Twilley, Robert R.; Sasser, Charles E.; Holm, Guerry O.
2017-05-01
Deltas are globally important locations of diverse ecosystems, human settlement, and economic activity that are threatened by reductions in sediment delivery, accelerated sea level rise, and subsidence. Here we investigated the relative contribution of river flooding, hurricanes, and cold fronts on elevation change in the prograding Wax Lake Delta (WLD). Sediment surface elevation was measured across 87 plots, eight times from February 2008 to August 2011. The high peak discharge river floods in 2008 and 2011 resulted in the greatest mean net elevation gain of 5.4 to 4.9 cm over each flood season, respectively. The highest deltaic wetland sediment retention (13.5% of total sediment discharge) occurred during the 2008 river flood despite lower total and peak discharge compared to 2011. Hurricanes Gustav and Ike resulted in a total net elevation gain of 1.2 cm, but the long-term contribution of hurricane derived sediments to deltaic wetlands was estimated to be just 22% of the long-term contribution of large river floods. Winter cold front passage resulted in a net loss in elevation that is equal to the elevation gain from lower discharge river floods and was consistent across years. This amount of annual loss in elevation from cold fronts could effectively negate the long-term land building capacity within the delta without the added elevation gain from both high and low discharge river floods. The current lack of inclusion of cold front elevation loss in most predictive numerical models likely overestimates the land building capacity in areas that experience similar forcings to WLD.
NASA Astrophysics Data System (ADS)
Rohrmann, A.; Alonso, R. N.; Sachse, D.; Mulch, A.; Pingel, H.; Tofelde, S.; Strecker, M. R.
2017-12-01
The growth of the Andean Plateau is one of the main controlling factors of present-day's South American climate and hydrological state and has played a major role in the evolution of species on 106 yr timescales. Yet, information about the timing of uplift and ensuing variability of climatic, hydrologic, and ecologic conditions are sparse. Reconstructions of topographic growth of mountain belts increasingly rely on leaf-wax hydrogen isotope data (δDwax), a paleo-hydrology proxy obtained from organic material in sedimentary rocks. However, establishing paleo-elevations have been hampered by the complexities associated with the δDwax signal, including changes in atmospheric circulation, atmospheric water-vapor transport, and evapo-transpiration. Rather than reconstructing absolute elevation changes, an alternative method involves to evaluate changes in δD (or δ18O) between low and high-elevation sites, Δ(δD) or Δ(δ18O) (δ-δ approach), and reference high-elevation δ18O or δD proxy data of precipitation to a (near-)sea-level record. We present a multi-isotope record with δDwax, δ13Cwax and δ18Ocarb on a well-dated sedimentary section from the 4-km-high Andean Plateau (Pastos Grandes Basin, 24°38' S, 66°40' W) and compare this record to an intermontane basin record (Angastaco Basin, 25°41' S, 66°04' W) located farther east in the E Cordillera to decipher patterns of hydrological changes during topographic growth. We show that over the last 9 Myr the eastern plateau margin experienced: (a) a variable influx of moisture and related changes in hydrologic conditions related to the onset of the South American Low-Level-Jet starting at 7.6 Ma; and (b) relative surface uplift on the order of 2 km between 9-4 Ma and later uplift of the intermonate basin after 5 Ma to its present-day elevation (using a δ-δ approach). This allows us to calculate an uplift rate of 0.8 km/Myr for the time between 9-4 Ma. The timing of uplift contradict earlier findings that most of the southern Andean Plateau had attained its high-elevation at least by 15 Ma or even as early as 38 Ma. Instead, we conclude that basins in the west attained elevation earlier during Andean mountain building, whereas basins farther east reached higher elevations later on, comparable to eastward-directed topographic growth observed in the Bolivian-Peruvian Altiplano.
Spatial and temporal variation of water temperature regimes on the Snoqualmie River network
Ashley E. Steel; Colin Sowder; Erin E. Peterson
2016-01-01
Although mean temperatures change annually and are highly correlated with elevation, the entire thermal regime on the Snoqualmie River, Washington, USA does not simply shift with elevation or season. Particular facets of the thermal regime have unique spatial patterns on the river network and at particular times of the year. We used a spatially and temporally dense...
Meadow Restoration in the Sawtooth National Recreation Area in Southern Idaho
John Sloan
2006-01-01
High elevation sites are ecologically fragile. When disturbed, these sites can take a long time to recover. However, native plant seeds are often unavailable and little is known about growing many of these plant species. This paper describes the cooperative restoration of a high elevation meadow in the Sawtooth National Recreation Area after a severe disturbance. The...
EXTERIOR VIEW, FRONT (NORTH) ELEVATION. THIS THREESTORY BRICK BUILDING WITH ...
EXTERIOR VIEW, FRONT (NORTH) ELEVATION. THIS THREE-STORY BRICK BUILDING WITH DEEPLY-BRACKETED AND OVERHANGING EAVES INCLUDES MULTIPLE BAYS CONSTRUCTED BEGINNING IN 1913 TO SERVE AS A 'CIVIC CENTER' FOR ACIPCO EMPLOYEES AND THEIR FAMILIES. THE BUILDING CURRENTLY INCLUDES THE TIME OFFICE, CAFETERIA, AND AUDITORIUM. - American Cast Iron Pipe Company, Service Building, 1501 Thirty-first Avenue North, Birmingham, Jefferson County, AL
[Liver enzymes elevation: etiologic study and efficiency of a single-act office visit].
Bendezú García, Rogger Álvaro; Casado Martín, Marta; Lázaro Sáez, Marta; Patrón Román, Gustavo Óliver; Gálvez Miras, Alejandra; Rodríguez Laiz, Gonzalo P; González Sánchez, Mercedes; Vega Sáenz, José Luis
2013-01-01
Liver enzyme (LE) elevation is a common finding in routine blood analysis. There is very little information on the most prevalent causes of these alterations in our population. In addition, a number of tests and several visits to the specialist are required to reach a diagnosis. For these reasons, we designed a protocol to streamline the evaluation of patients with LE elevations in a single-act office visit. From March 2008 until June 2010, we studied all patients with incidental LE elevation (isolated transaminase elevation, combined elevation of alkaline phosphatase [FA] and gamma-glutamyl transpeptidase [GGT], or isolated elevation of GGT) who were referred by their primary care physicians. At the time of referral, a complete biochemistry analysis was performed (LE, viral serology, autoantibodies, ceruloplasmin, iron metabolism, alpha-1-antitrypsin and thyroid hormones) and the patients underwent an abdominal ultrasound scan on the day of the office evaluation by the hepatologist. A total of 427 patients were included in our study. The most common cause of transaminase elevation was non-alcoholic fatty liver disease (NAFLD) (40%), followed by alcohol intake (17%), and hepatitis C virus infection (13%). Elevated GGT levels were most commonly related to NAFLD (30%), closely followed by alcohol intake (27%), and hepatotoxicity (8%). Combined elevation of GGT and FA was associated with NAFLD (21%), alcohol (17%), and hepatotoxicity (11%). Self-limited elevation was seen in 9% of the patients and we could not identify a definite cause in 11%. A definitive diagnosis was reached in 79% of the patients. The single-act office visit has proven to be efficient, yielding a diagnosis in most of the patients. The most common cause of elevated LE was NAFLD. Transaminase elevation must be confirmed before a more thorough work-up is started. Copyright © 2013 Elsevier España, S.L. and AEEH y AEG. All rights reserved.
Decadal changes of surface elevation over permafrost area estimated using reflected GPS signals
NASA Astrophysics Data System (ADS)
Liu, Lin; Larson, Kristine M.
2018-02-01
Conventional benchmark-based survey and Global Positioning System (GPS) have been used to measure surface elevation changes over permafrost areas, usually once or a few times a year. Here we use reflected GPS signals to measure temporal changes of ground surface elevation due to dynamics of the active layer and near-surface permafrost. Applying the GPS interferometric reflectometry technique to the multipath signal-to-noise ratio data collected by a continuously operating GPS receiver mounted deep in permafrost in Barrow, Alaska, we can retrieve the vertical distance between the antenna and reflecting surface. Using this unique kind of observables, we obtain daily changes of surface elevation during July and August from 2004 to 2015. Our results show distinct temporal variations at three timescales: regular thaw settlement within each summer, strong interannual variability that is characterized by a sub-decadal subsidence trend followed by a brief uplift trend, and a secular subsidence trend of 0.26 ± 0.02 cm year-1 during 2004 and 2015. This method provides a new way to fully utilize data from continuously operating GPS sites in cold regions for studying dynamics of the frozen ground consistently and sustainably over a long time.
Changes in Body Mass Index and the Trajectory of Depressive Symptoms Among Rural Men and Women.
Chang, Jen Jen; Salas, Joanne; Tabet, Maya; Kasper, Zachary; Elder, Keith; Staley, Holly; Brownson, Ross C
2017-04-01
This study examined the association between body mass index (BMI) changes over time and the risk of elevated depressive symptoms in a cohort of Midwestern rural adults. The longitudinal study used data from a telephone survey in 2005 including 1,475 men and women enrolled in the Walk the Ozarks to Wellness Project from 12 rural communities in Missouri, Arkansas, and Tennessee. Multilevel random intercept mixed models were used to estimate adjusted odds ratios (aOR) and 95% confidence intervals (CI) for the association between BMI calculated from self-reported height and body weight and elevated depressive symptoms, adjusting for sociodemographic, behavioral, and medical variables. Elevated depressive symptoms were common in this rural population (17%-19%) and the mean BMI was 28 kg/m 2 . For each unit increase in BMI over time, representing an average increase of about 5.8 pounds from baseline weight, there was a 6% increased odds of elevated depressive symptoms (aOR: 1.06, 95% CI: 1.02-1.12). Our findings hold important public health implications given the increasing rates of overweight and obesity over the past couple of decades, particularly among rural adults. © 2016 National Rural Health Association.
Sebok, Eva; Engesgaard, Peter; Duque, Carlos
2017-08-24
This study presented the monitoring and quantification of streambed sedimentation and scour in a stream with dynamically changing streambed based on measured phase and amplitude of the diurnal signal of sediment temperature time series. With the applied method, changes in streambed elevation were estimated on a sub-daily scale with 2-h intervals without continuous maintenance of the measurement system, thus making both high temporal resolution and long-term monitoring of streambed elevations possible. Estimates of streambed elevation showed that during base flow conditions streambed elevation fluctuates by 2-3 cm. Following high stream stages, scouring of 2-5 cm can be observed even at areas with low stream flow and weak currents. Our results demonstrate that weather variability can induce significant changes in the stream water and consequently sediment temperatures influencing the diurnal temperature signal in such an extent that the sediment thickness between paired temperature sensors were overestimated by up to 8 cm. These observations have significant consequences on the design of vertical sensor spacing in high-flux environments and in climates with reduced diurnal variations in air temperature.
Djossou, Félix; Vesin, Guillaume; Walter, Gaelle; Epelboin, Loïc; Mosnier, Emilie; Bidaud, Bastien; Abboud, Philippe; Okandze, Antoine; Mattheus, Severine; Elenga, Narcisse; Demar, Magalie; Malvy, Denis; Nacher, Mathieu
2016-02-01
The objective of the study was to determine the incidence of transaminase elevation during dengue, and its predictive factors. In 2013, a longitudinal study was performed using data from all cases of dengue seen in Cayenne Hospital. Cox proportional modeling was used. Signs of major transaminase elevation were defined as an increase in aspartate amino transferase (AST) or alanine amino transferase (ALT) concentration over 10 times the normal value (10N). There were 1574 patients and 13 249 person-days of follow-up. The incidence rate for signs of transaminase elevation (10N) was 0.55 per 100 person-days. Six patients had major transaminase elevation with AST>1000 units (0.43 per 1000 patient-days), and 73 patients (4.6%) developed transaminase elevation with AST >10N. The variables independently associated with major transaminase elevation were hyponatremia, low platelets, dehydration, hematocrit increase, food intolerance, positive nonstructural protein 1 (NS1), age over 15 years and the notion of paracetamol intake. Although very frequent, the incidence of major transaminase elevation was lower than reported elsewhere perhaps because of good access to care, or of the particular serotype causing this epidemic. The patients with transaminase elevation tended to be older, more severe and taking paracetamol. . © The Author 2016. Published by Oxford University Press on behalf of Royal Society of Tropical Medicine and Hygiene. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bauer, Stephen J.
The elevation change data measured at the Bryan Mound Strategic Petroleum Reserve (SPR) site over the last 16+ years has been studied and a model utilized to project elevation changes into the future. The subsidence rate at Bryan Mound is low in comparison with other Strategic Petroleum Reserve sites and has decreased with time due to the maintenance of higher operating pressures and the normal decrease in creep closure rate of caverns with time. However, the subsidence at the site is projected to continue. A model was developed to project subsidence values 20 years into the future; no subsidence relatedmore » issues are apparent from these projections.« less
Global multi-resolution terrain elevation data 2010 (GMTED2010)
Danielson, Jeffrey J.; Gesch, Dean B.
2011-01-01
In 1996, the U.S. Geological Survey (USGS) developed a global topographic elevation model designated as GTOPO30 at a horizontal resolution of 30 arc-seconds for the entire Earth. Because no single source of topographic information covered the entire land surface, GTOPO30 was derived from eight raster and vector sources that included a substantial amount of U.S. Defense Mapping Agency data. The quality of the elevation data in GTOPO30 varies widely; there are no spatially-referenced metadata, and the major topographic features such as ridgelines and valleys are not well represented. Despite its coarse resolution and limited attributes, GTOPO30 has been widely used for a variety of hydrological, climatological, and geomorphological applications as well as military applications, where a regional, continental, or global scale topographic model is required. These applications have ranged from delineating drainage networks and watersheds to using digital elevation data for the extraction of topographic structure and three-dimensional (3D) visualization exercises (Jenson and Domingue, 1988; Verdin and Greenlee, 1996; Lehner and others, 2008). Many of the fundamental geophysical processes active at the Earth's surface are controlled or strongly influenced by topography, thus the critical need for high-quality terrain data (Gesch, 1994). U.S. Department of Defense requirements for mission planning, geographic registration of remotely sensed imagery, terrain visualization, and map production are similarly dependent on global topographic data. Since the time GTOPO30 was completed, the availability of higher-quality elevation data over large geographic areas has improved markedly. New data sources include global Digital Terrain Elevation Data (DTEDRegistered) from the Shuttle Radar Topography Mission (SRTM), Canadian elevation data, and data from the Ice, Cloud, and land Elevation Satellite (ICESat). Given the widespread use of GTOPO30 and the equivalent 30-arc-second DTEDRegistered level 0, the USGS and the National Geospatial-Intelligence Agency (NGA) have collaborated to produce an enhanced replacement for GTOPO30, the Global Land One-km Base Elevation (GLOBE) model and other comparable 30-arc-second-resolution global models, using the best available data. The new model is called the Global Multi-resolution Terrain Elevation Data 2010, or GMTED2010 for short. This suite of products at three different resolutions (approximately 1,000, 500, and 250 meters) is designed to support many applications directly by providing users with generic products (for example, maximum, minimum, and median elevations) that have been derived directly from the raw input data that would not be available to the general user or would be very costly and time-consuming to produce for individual applications. The source of all the elevation data is captured in metadata for reference purposes. It is also hoped that as better data become available in the future, the GMTED2010 model will be updated.
Vandenbruwaene, W.; Maris, T.; Cahoon, D.R.; Meire, P.; Temmerman, S.
2011-01-01
Along coasts and estuaries, formerly embanked land is increasingly restored into tidal marshes in order to re-establish valuable ecosystem services, such as buffering against flooding. Along the Scheldt estuary (Belgium), tidal marshes are restored on embanked land by allowing a controlled reduced tide (CRT) into a constructed basin, through a culvert in the embankment. In this way tidal water levels are significantly lowered (ca. 3 m) so that a CRT marsh can develop on formerly embanked land with a ca. 3 m lower elevation than the natural tidal marshes. In this study we compared the long-term change in elevation (ΔE) within a CRT marsh and adjacent natural tidal marsh. Over a period of 4 years, the observed spatio-temporal variations in ΔE rate were related to variations in inundation depth, and this relationship was not significantly different for the CRT marsh and natural tidal marsh. A model was developed to simulate the ΔE over the next century. (1) Under a scenario without mean high water level (MHWL) rise in the estuary, the model shows that the marsh elevation-ΔE feedback that is typical for a natural tidal marsh (i.e. rising marsh elevation results in decreasing inundation depth and therefore a decreasing increase in elevation) is absent in the basin of the CRT marsh. This is because tidal exchange of water volumes between the estuary and CRT marsh are independent from the CRT marsh elevation but dependent on the culvert dimensions. Thus the volume of water entering the CRT remains constant regardless of the marsh elevation. Consequently the CRT MHWL follows the increase in CRT surface elevation, resulting after 75 years in a 2–2.5 times larger elevation gain in the CRT marsh, and a faster reduction of spatial elevation differences. (2) Under a scenario of constant MHWL rise (historical rate of 1.5 cm a-1), the equilibrium elevation (relative to MHWL) is 0.13 m lower in the CRT marsh and is reached almost 2 times faster. (3) Under a scenario of accelerated MHWL rise (acceleration of 0.02 cm a-1), the CRT marsh is much less able to keep up with the MHWL rise; after 75 years the CRT elevation is already 0.21 m lower than for the natural marsh. In conclusion, this study demonstrates that although short-term (4 years) ΔE rates are similar in a restored CRT marsh and natural tidal marsh, these ecosystems may evolve differently in response to sea-level rise in the longer term (10–100 years).
Time-dependent crack growth behavior of alloy 617 and alloy 230 at elevated temperatures
NASA Astrophysics Data System (ADS)
Roy, Shawoon Kumar
2011-12-01
Two Ni-base solid-solution-strengthened superalloys: INCONEL 617 and HAYNES 230 were studied to check sustained loading crack growth (SLCG) behavior at elevated temperatures appropriate for Next Generation Nuclear Plant (NGNP) applictaions with constant stress intensity factor (Kmax= 27.75 MPa✓m) in air. The results indicate a time-dependent rate controlling process which can be characterized by a linear elastic fracture mechanics (LEFM) parameter -- stress intensity factor (K). At elevated temperatures, the crack growth mechanism was best described using a damage zone concept. Based on results and study, SAGBOE (stress accelerated grain boundary oxidation embrittlement) is considered the primary reason for time-dependent SLCG. A thermodynamic equation was considered to correlate all the SLCG results to determine the thermal activation energy in the process. A phenomenological model based on a time-dependent factor was developed considering the previous researcher's time-dependent fatigue crack propagation (FCP) results and current SLCG results to relate cycle-dependent and time-dependent FCP for both alloys. Further study includes hold time (3+300s) fatigue testing and no hold (1s) fatigue testing with various load ratios (R) at 700°C with a Kmax of 27.75 MPa✓m. Study results suggest an interesting point: crack growth behavior is significantly affected with the change in R value in cycle-dependent process whereas in time-dependent process, change in R does not have any significant effect. Fractography study showed intergranular cracking mode for all time-dependent processes and transgranular cracking mode for cycle-dependent processes. In Alloy 230, SEM images display intergranular cracking with carbide particles, dense oxides and dimple mixed secondary cracks for time-dependent 3+300s FCP and SLCG test. In all cases, Alloy 230 shows better crack growth resistance compared to Alloy 617.
Kanezaki, Akio; Hirata, Akimasa; Watanabe, Soichi; Shirai, Hiroshi
2010-08-21
The present study describes theoretical parametric analysis of the steady-state temperature elevation in one-dimensional three-layer (skin, fat and muscle) and one-layer (skin only) models due to millimeter-wave exposure. The motivation of this fundamental investigation is that some variability of warmth sensation in the human skin has been reported. An analytical solution for a bioheat equation was derived by using the Laplace transform for the one-dimensional human models. Approximate expressions were obtained to investigate the dependence of temperature elevation on different thermal and tissue thickness parameters. It was shown that the temperature elevation on the body surface decreases monotonically with the blood perfusion rate, heat conductivity and heat transfer from the body to air. Also revealed were the conditions where maximum and minimum surface temperature elevations were observed for different thermal and tissue thickness parameters. The surface temperature elevation in the three-layer model is 1.3-2.8 times greater than that in the one-layer model. The main reason for this difference is attributed to the adiabatic nature of the fat layer. By considering the variation range of thermal and tissue thickness parameters which causes the maximum and minimum temperature elevations, the dominant parameter influencing the surface temperature elevation was found to be the heat transfer coefficient between the body surface and air.
Kuhli-Hattenbach, C; Hellstern, P; Miesbach, W; Kohnen, T; Hattenbach, L-O
2018-01-01
The potential impact of elevated Lipoprotein (a) [Lp(a)] levels on retinal venous occlusive (RVO) diseases with regard to age and various risk factors has not been studied extensively. In a retrospective case-control study, thrombophilia data of 106 young patients (< 60 years at the time of the RVO or a previous thromboembolic event) with RVO and 76 healthy subjects were evaluated. Elevated Lp(a) plasma levels were significantly more prevalent among RVO patients (29.2 %) than among controls (9.2 %; p = 0.0009). Lp(a) levels were found to be significantly (p = 0.012) different between patients and controls. Moreover, we found that an unusual personal or family history of thromboembolism was a strong predictor of elevated Lp(a) (p = 0.03). We observed a significant correlation between elevated Lp(a) and other coagulation disorders (p = 0.005). Multivariate analysis showed that elevated lipoprotein(a) levels (OR: 3.5; p = 0.003) were an independent risk factor for the development of RVO. Elevated plasma levels of Lp(a) are associated with the development of RVO. Selective screening of young patients and subjects with a personal or family history of thromboembolism may be helpful in identifying RVO patients with elevated Lp(a). Georg Thieme Verlag KG Stuttgart · New York.
On the value of routine prothrombin time screening in elective neurosurgical procedures.
Dützmann, Stephan; Gessler, Florian; Marquardt, Gerhard; Seifert, Volker; Senft, Christian
2012-11-01
The authors performed a study to evaluate whether preoperative assessment of prothrombin time (PT) is mandatory in patients undergoing routinely planned neurosurgical procedures. The charts of all patients admitted to general wards of the authors' department for routinely planned surgery (excluding trauma and ICU patients) between 2006 and 2010 were retrospectively reviewed. The authors assessed preoperative PT and the clinical courses of all patients, with special consideration for patients receiving coagulation factor substitution. All cases involving hemorrhagic complications were analyzed in detail with regard to pre- and postoperative PT abnormalities. Prothrombin time was expressed as the international normalized ratio, and values greater than 1.28 were regarded as elevated. Clinical courses and PT values of 4310 patients were reviewed. Of these, 33 patients (0.7%) suffered hemorrhagic complications requiring repeat surgery. Thirty-one patients (94%) had a normal PT before the initial operation, while 2 patients had slightly elevated PT values of 1.33 and 1.65, which were anticipated based on the patient's history. In the latter 2 cases, surgery was performed without prior correction of PT. Preoperatively, PT was elevated in 78 patients (1.8%). In 73 (93.6%) of the 78 patients, the PT elevation was expected and explained by each patient's medical history. In only 5 (0.1%) of 4310 patients did we find an unexpected PT elevation (mean 1.53, range 1.37-1.74). All 5 patients underwent surgery without complications, while 2 had received coagulation factor substitution preoperatively, as requested by the surgeon, because of an estimated risk of bleeding complications. None of the 5 patients received coagulation factor substitution postoperatively, and later detailed laboratory studies ruled out single coagulation factor deficiencies. There was no statistically significant association between preoperatively elevated PT levels and the occurrence of hemorrhagic complications (p = 0.12). Before the second procedure but not before the initial operation, 4 (12%) of the 33 patients had elevated PT. The findings suggest that the value of preoperative PT testing is limited in patients in whom a normal history can be ascertained. Close postoperative PT control is necessary in every neurosurgical patient, and better tests need to be developed to identify patients who are prone to hemorrhagic complications.
Measuring reactive hyperemia in the lower limb using near-infrared spectroscopy
NASA Astrophysics Data System (ADS)
Willingham, Thomas B.; Southern, William M.; McCully, Kevin K.
2016-09-01
Near-infrared spectroscopy (NIRS) has been used to measure reactive hyperemia following a vascular occlusion. However, the procedures and methods of analysis used have varied. The purpose of the present study is to identify reproducible methods for measuring reactive hyperemia using HbO2 NIRS signals in the calf and foot. Healthy participants (10 male, 10 female) aged 19 to 28 years performed one of two tests: reproducibility trials or elevation protocol (30 and 60 cm limb elevation above the heart). The time to 50% reperfusion (T) and the second (R2q) quartile rates of reperfusion were found to be the most reproducible parameters (coefficient of variation=7.12 to 14.1%). The time to 95% reperfusion (T95) was 12.7% more reproducible on average than the previously reported parameter of time to peak hyperemia. Measures of reperfusion time and rate slowed with increasing limb elevation. Correlations were identified between the calf and foot in the measurements of R2q (R2=0.713, p=0.021), T (R2=0.673, p=0.033), and T95 (R2=0.792, p=0.006). Half and 95% recovery times and second and third quartile rates expressed good reproducibility and sensitivity to change with reduced perfusion pressure. NIRS measures of reactive hyperemia have the potential to evaluate microvascular perfusion in clinical populations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Jeong, Dae-Ho; Choi, Myung-Je; Goto, Masahiro
In this study, the fatigue crack propagation behavior of Inconel 718 turbine disc with different service times from 0 to 4229 h was investigated at 738 and 823 K. No notable change in microstructural features, other than the increase in grain size, was observed with increasing service time. With increasing service time from 0 to 4229 h, the fatigue crack propagation rates tended to increase, while the ΔK{sub th} value decreased, in low ΔK regime and lower Paris' regime at both testing temperatures. The fractographic observation using a scanning electron microscope suggested that the elevated temperature fatigue crack propagation mechanismmore » of Inconel 718 changed from crystallographic cleavage mechanism to striation mechanism in the low ΔK regime, depending on the grain size. The fatigue crack propagation mechanism is proposed for the crack propagating through small and large grains in the low ΔK regime, and the fatigue crack propagation behavior of Inconel 718 with different service times at elevated temperatures is discussed. - Highlights: • The specimens were prepared from the Inconel 718 turbine disc used for 0 to 4229 h. • FCP rates were measured at 738 and 823 K. • The ΔK{sub th} values decreased with increasing service time. • The FCP behavior showed a strong correlation with the grain size of used turbine disc.« less
Pellegrini, Lucienne; Parrilli, Gianpaolo; Santonicola, Antonella; Cinquanta, Luigi; Caputo, Cesare; Ciacci, Carolina; Zingone, Fabiana
2017-01-01
The relevance of isolated autoimmunity elevation in orthotopic liver transplantation (OLT) patients is unknown. Our aim was to analyse how serum autoantibodies change in time and to evaluate their clinical relevance in OLT patients. Patients were invited to provide samples to evaluate ANA, AMA, ASMA, and LKM at the time of enrolment ( T 0), after 6 months ( T 6), and after 12 months ( T 12). We included 114 patients in the study (76% males, median age 62.5 years), finding isolated elevation of at least one serum antibody in up to 80% of them. We described fluctuating positive autoantibodies in the one year of observation, with only 45.6% of patients positive for ANA and less than 2% positive for ASMA, at all three times. Isolated elevation of tissue antibodies was not related to gender, age, HCC at transplant, early rejection, cause of transplantation, immunotherapy taken, and age at the time of the study. We did not detect a higher prevalence of positive autoimmunity in patients with signs of liver injury. ANA and ASMA evaluation in patients with liver transplantation and no history of autoimmune disease has no clinical relevance, since it varies in time and is not related to any risk factors or liver injury. Routine autoimmunity evaluation should be avoided.
Pellegrini, Lucienne; Parrilli, Gianpaolo; Santonicola, Antonella; Cinquanta, Luigi; Caputo, Cesare
2017-01-01
The relevance of isolated autoimmunity elevation in orthotopic liver transplantation (OLT) patients is unknown. Our aim was to analyse how serum autoantibodies change in time and to evaluate their clinical relevance in OLT patients. Patients were invited to provide samples to evaluate ANA, AMA, ASMA, and LKM at the time of enrolment (T0), after 6 months (T6), and after 12 months (T12). We included 114 patients in the study (76% males, median age 62.5 years), finding isolated elevation of at least one serum antibody in up to 80% of them. We described fluctuating positive autoantibodies in the one year of observation, with only 45.6% of patients positive for ANA and less than 2% positive for ASMA, at all three times. Isolated elevation of tissue antibodies was not related to gender, age, HCC at transplant, early rejection, cause of transplantation, immunotherapy taken, and age at the time of the study. We did not detect a higher prevalence of positive autoimmunity in patients with signs of liver injury. ANA and ASMA evaluation in patients with liver transplantation and no history of autoimmune disease has no clinical relevance, since it varies in time and is not related to any risk factors or liver injury. Routine autoimmunity evaluation should be avoided. PMID:28337446
Continuous Wavelet Transform Analysis of Acceleration Signals Measured from a Wave Buoy
Chuang, Laurence Zsu-Hsin; Wu, Li-Chung; Wang, Jong-Hao
2013-01-01
Accelerometers, which can be installed inside a floating platform on the sea, are among the most commonly used sensors for operational ocean wave measurements. To examine the non-stationary features of ocean waves, this study was conducted to derive a wavelet spectrum of ocean waves and to synthesize sea surface elevations from vertical acceleration signals of a wave buoy through the continuous wavelet transform theory. The short-time wave features can be revealed by simultaneously examining the wavelet spectrum and the synthetic sea surface elevations. The in situ wave signals were applied to verify the practicality of the wavelet-based algorithm. We confirm that the spectral leakage and the noise at very-low-frequency bins influenced the accuracies of the estimated wavelet spectrum and the synthetic sea surface elevations. The appropriate thresholds of these two factors were explored. To study the short-time wave features from the wave records, the acceleration signals recorded from an accelerometer inside a discus wave buoy are analysed. The results from the wavelet spectrum show the evidence of short-time nonlinear wave events. Our study also reveals that more surface profiles with higher vertical asymmetry can be found from short-time nonlinear wave with stronger harmonic spectral peak. Finally, we conclude that the algorithms of continuous wavelet transform are practical for revealing the short-time wave features of the buoy acceleration signals. PMID:23966188
Late Pleistocene temperature, hydrology, and glaciation in equatorial East Africa
NASA Astrophysics Data System (ADS)
Russell, J. M.; Verschuren, D.; Kelly, M. A.; Loomis, S. E.; Jackson, M. S.; Morrill, C.; S Sinninghe Damsté, J.; Doughty, A. M.; De Cort, G.; Olago, D.; Street-Perrott, F. A.
2016-12-01
In the coming century the world's high tropical mountains are predicted to experience a magnitude of climate change second only to the Arctic due to amplification of warming with elevation in the tropics. Proxy data suggest that substantial changes in tropical temperature and hydroclimate also occurred during the last deglaciation, the most recent time period when rising atmospheric CO2 concentrations caused large changes in global climate. Determining whether the rate of temperature change with elevation (the lapse rate) was different from today during the Last Glacial Maximum (LGM) is therefore critical to understanding the future of tropical mountain environments and resources. Here we present a new 25,000-year temperature reconstruction based upon organic geochemical analyses of sediment cores from Lake Rutundu (3,078 m asl), Mount Kenya, East Africa. Through comparison with regional reconstructions of lower elevation temperature, we show that LGM cooling was amplified with elevation and hence that the lapse rate was significantly steeper than today. Comparison of our lapse rate reconstructions with equilibrium line altitude reconstructions from glacial moraines indicates that temperature, rather than precipitation, was the dominant control on tropical alpine glacier fluctuations at this time scale. Nevertheless, our results have important implications for the tropical hydrological cycle, as changes in the lapse rate are intimately linked with changes in atmospheric water vapour concentrations. Indeed, we attribute the steeper lapse rate to drying of the tropical ice-age atmosphere, a hypothesis supported by palaeoclimate models. However, comparison of our data to these simulations indicates that state-of-the-art models significantly underestimate tropical temperature changes at high elevation and therefore the lapse-rate change. Consequently, future high-elevation tropical warming may be even greater than currently predicted.
Bradford, David F.; Stanley, Kerri; McConnell, Laura L.; Tallent-Halsell, Nita G.; Nash, Maliha S.; Simonich, Staci M.
2011-01-01
Atmospherically deposited contaminants in the Sierra Nevada mountains of California, USA have been implicated as adversely affecting amphibians and fish, yet little is known about the distributions of contaminants within the mountains, particularly at high elevation. We tested the hypothesis that contaminant concentrations in a high-elevation portion of the Sierra Nevada decrease with distance from the adjacent San Joaquin Valley. We sampled air, sediment, and tadpoles twice at 28 water bodies in 14 dispersed areas in Sequoia and Kings Canyon National Parks (2785 – 3375 m elevation; 43 – 82 km from Valley edge). We detected up to 15 chemicals frequently in sediment and tadpoles, including current- and historic-use pesticides, polychlorinated biphenyls, and polycyclic aromatic hydrocarbons. Only β-endosulfan was found frequently in air. Concentrations of all chemicals detected were very low, averaging in the parts-per-billion range or less in sediment and tadpoles, and on the order of 10 pg/m3 for β-endosulfan in air. Principal components analysis indicated that chemical compositions were generally similar among sites, suggesting that chemical transport patterns were likewise similar among sites. In contrast, transport processes did not appear to strongly influence concentration differences among sites because variation in concentrations among nearby sites was high relative to sites far from each other. Moreover, a general relationship for concentrations as a function of distance from the valley was not evident across chemical, medium, and time. Nevertheless, concentrations for some chemical/medium/time combinations showed significant negative relationships with metrics for distance from the Valley. However, the magnitude of these distance effects among high-elevation sites was small relative to differences found in other studies between the valley edge and the nearest high-elevation sites. PMID:20821540
NASA Astrophysics Data System (ADS)
Hoke, Gregory D.; Giambiagi, Laura B.; Garzione, Carmala N.; Mahoney, J. Brian; Strecker, Manfred R.
2014-11-01
The topographic growth of mountain ranges at convergent margins results from the complex interaction between the motion of lithospheric plates, crustal shortening, rock uplift and exhumation. Constraints on the timing and magnitude of elevation change gleaned from isotopic archives preserved in sedimentary sequences provide insight into how these processes interact over different timescales to create topography and potentially decipher the impact of topography on atmospheric circulation and superposed exhumation. This study uses stable isotope data from pedogenic carbonates collected from seven different stratigraphic sections spanning different tectonic and topographic positions in the range today, to examine the middle to late Miocene history of elevation change in the central Andes thrust belt, which is located immediately to the south of the Altiplano-Puna Plateau, the world's second largest orogenic plateau. Paleoelevations are calculated using previously published local isotope-elevation gradients observed in modern rainfall and carbonate-formation temperatures determined from clumped isotope studies in modern soils. Calculated Neogene basin paleoelevations are between 1 km and 1.9 km for basins that today are located between 1500 and 3400 m elevation. Considering the modern elevation and δ18O values of precipitation at the sampling sites, three of the intermontane basins experienced surface uplift between the end of deposition during the late Miocene and present. The timing of elevation change cannot be linked to any documented episodes of large-magnitude crustal shortening. Paradoxically, the maximum inferred surface uplift in the core of the range is greatest where the crust is thinnest. The spatial pattern of surface uplift is best explained by eastward migration of a crustal root via ductile deformation in the lower crust and is not related to flat-slab subduction.
Li, Yanfeng; Wang, Fuli; Hu, Pin; Fan, Jiadong; Han, Yishi; Liu, Bin; Liu, Tao; Yang, Chunhao; Gu, Xiangmin
2016-01-01
Osteotome sinus floor elevation is a less invasive approach to augment an insufficient alveolar bone at the posterior maxilla for dental implantation. However, this approach has some limitations due to the lack of sinus lift tools available for clinical use and the small transcrestal access to the maxillary sinus floor. We recently invented shape-memory Ni/Ti alloy wire containing tube elevators for transcrestal detaching maxillary sinus mucosa, and developed goat ex vivo models for direct visualizing the effectiveness of detaching sinus mucosa in real time during transcrestal maxillary sinus floor elevation. We evaluated our invented elevators, namely elevator 012 and elevator 014, for their effectiveness for transcrestal detaching maxillary sinus mucosa using the goat ex vivo models. We measured the length of sinus mucosa detached in mesial and distal directions or buccal and palatal directions, and the space volume created by detaching maxillary sinus mucosa in mesial, distal, buccal and palatal directions using the invented elevators. Elevator 012 had a shape-memory Ni/Ti alloy wire with a diameter of 0.012 inch, while elevator 014 had its shape-memory Ni/Ti alloy wire with a diameter of 0.014 inch. Elevator 012 could detach the goat maxillary sinus mucosa in the mesial or distal direction for 12.1±4.3 mm, while in the buccal or palatal direction for 12.5±6.7 mm. The elevator 014 could detach the goat maxillary sinus mucosa for 23.0±4.9 mm in the mesial or distal direction, and for 19.0±8.1 mm in the buccal or palatal direction. An average space volume of 1.7936±0.2079 ml was created after detaching the goat maxillay sinus mucosa in both mesial/distal direction and buccal/palatal direction using elevator 012; while the average space volume created using elevator 014 was 1.8764±0.2366 ml. Both two newly invented tube elevators could effectively detach the maxillary sinus mucosa on the goat ex vivo sinus models. Moreover, elevator 014 has advantages over the elevator 012 for the capability to detach sinus mucosa. © 2016 The Author(s) Published by S. Karger AG, Basel.
Characterization of within-day beginning times of storms for stochastic simulation
USDA-ARS?s Scientific Manuscript database
The beginning times of storms within a day are often required for stochastic modeling purposes and for studies on plant growth. This study investigated the variation in frequency distributions of storm-initiation time (SI time) within a day due to elevation changes and month. Actual storms without 2...
Analytical Incorporation of Velocity Parameters into Ice Sheet Elevation Change Rate Computations
NASA Astrophysics Data System (ADS)
Nagarajan, S.; Ahn, Y.; Teegavarapu, R. S. V.
2014-12-01
NASA, ESA and various other agencies have been collecting laser, optical and RADAR altimetry data through various missions to study the elevation changes of the Cryosphere. The laser altimetry collected by various airborne and spaceborne missions provides multi-temporal coverage of Greenland and Antarctica since 1993 to now. Though these missions have increased the data coverage, considering the dynamic nature of the ice surface, it is still sparse both spatially and temporally for accurate elevation change detection studies. The temporal and spatial gaps are usually filled by interpolation techniques. This presentation will demonstrate a method to improve the temporal interpolation. Considering the accuracy, repeat coverage and spatial distribution, the laser scanning data has been widely used to compute elevation change rate of Greenland and Antarctica ice sheets. A major problem with these approaches is non-consideration of ice sheet velocity dynamics into change rate computations. Though the correlation between velocity and elevation change rate have been noticed by Hurkmans et al., 2012, the corrections for velocity changes were applied after computing elevation change rates by assuming linear or higher polynomial relationship. This research will discuss the possibilities of parameterizing ice sheet dynamics as unknowns (dX and dY) in the adjustment mathematical model that computes elevation change (dZ) rates. It is a simultaneous computation of changes in all three directions of the ice surface. Also, the laser points between two time epochs in a crossover area have different distribution and count. Therefore, a registration method that does not require point-to-point correspondence is required to recover the unknown elevation and velocity parameters. This research will experiment the possibilities of registering multi-temporal datasets using volume minimization algorithm, which determines the unknown dX, dY and dZ that minimizes the volume between two or more time-epoch point clouds. In order to make use of other existing data as well as to constrain the adjustment, InSAR velocity will be used as initial values for the parameters dX and dY. The presentation will discuss the results of analytical incorporation of parameters and the volume based registration method for a test site in Greenland.
Circulatory nucleosome levels are significantly increased in early and late-onset preeclampsia.
Zhong, Xiao Yan; Gebhardt, Stefan; Hillermann, Renate; Tofa, Kashefa Carelse; Holzgreve, Wolfgang; Hahn, Sinuhe
2005-08-01
Elevations in circulatory DNA, as measured by real-time PCR, have been observed in pregnancies with manifest preeclampsia. Recent reports have indicated that circulatory nucleosome levels are elevated in the periphery of cancer patients. We have now examined whether circulatory nucleosome levels are similarly elevated in cases with preeclampsia. Maternal plasma samples were prepared from 17 cases with early onset preeclampsia (<34 weeks gestation) with 14 matched normotensive controls, as well as 15 cases late-onset preeclampsia (>34 weeks gestation) with 10 matched normotensive controls. Levels of circulatory nucleosomes were quantified by commercial ELISA (enzyme-linked immunosorbant assay). The level of circulatory nucleosomes was significantly elevated in both study preeclampsia groups, compared to the matched normotensive control group (p = 0.000 and p = 0.001, respectively). Our data suggests that preeclampsia is associated with the elevated presence of circulatory nucleosomes, and that this phenomenon occurs in both early- and late-onset forms of the disorder. Copyright 2005 John Wiley & Sons, Ltd.
A 10-Fr ultrasound catheter with integrated micromotor for 4-D intracardiac echocardiography.
Lee, Warren; Griffin, Weston; Wildes, Douglas; Buckley, Donald; Topka, Terry; Chodakauskas, Thaddeus; Langer, Mark; Calisti, Serge; Bergstøl, Svein; Malacrida, Jean-Pierre; Lanteri, Frédéric; Maffre, Jennifer; McDaniel, Ben; Shivkumar, Kalyanam; Cummings, Jennifer; Callans, David; Silvestry, Frank; Packer, Douglas
2011-07-01
We developed prototype real-time 3-D intracardiac echocardiography catheters with integrated micromotors, allowing internal oscillation of a low-profile 64-element, 6.2-MHz phased-array transducer in the elevation direction. Components were designed to facilitate rotation of the array, including a low-torque flexible transducer interconnect and miniature fixtures for the transducer and micromotor. The catheter tip prototypes were integrated with two-way deflectable 10-Fr catheters and used in in vivo animal testing at multiple facilities. The 4-D ICE catheters were capable of imaging a 90° azimuth by up to 180° elevation field of view. Volume rates ranged from 1 vol/sec (180° elevation) to approximately 10 vol/sec (60° elevation). We successfully imaged electrophysiology catheters, atrial septal puncture procedures, and detailed cardiac anatomy. The elevation oscillation enabled 3-D visualization of devices and anatomy, providing new clinical information and perspective not possible with current 2-D imaging catheters.
Lithium suppression of tau induces brain iron accumulation and neurodegeneration.
Lei, P; Ayton, S; Appukuttan, A T; Moon, S; Duce, J A; Volitakis, I; Cherny, R; Wood, S J; Greenough, M; Berger, G; Pantelis, C; McGorry, P; Yung, A; Finkelstein, D I; Bush, A I
2017-03-01
Lithium is a first-line therapy for bipolar affective disorder. However, various adverse effects, including a Parkinson-like hand tremor, often limit its use. The understanding of the neurobiological basis of these side effects is still very limited. Nigral iron elevation is also a feature of Parkinsonian degeneration that may be related to soluble tau reduction. We found that magnetic resonance imaging T 2 relaxation time changes in subjects commenced on lithium therapy were consistent with iron elevation. In mice, lithium treatment lowers brain tau levels and increases nigral and cortical iron elevation that is closely associated with neurodegeneration, cognitive loss and parkinsonian features. In neuronal cultures lithium attenuates iron efflux by lowering tau protein that traffics amyloid precursor protein to facilitate iron efflux. Thus, tau- and amyloid protein precursor-knockout mice were protected against lithium-induced iron elevation and neurotoxicity. These findings challenge the appropriateness of lithium as a potential treatment for disorders where brain iron is elevated (for example, Alzheimer's disease), and may explain lithium-associated motor symptoms in susceptible patients.
Advanced Space Transportation Program (ASTP)
2000-09-07
The `once upon a time' science fiction concept of a space elevator has been envisioned and studied as a real mass transportation system in the latter part of the 21st century. David Smitherman of NASA's Marshall Space Flight Center's Advanced Projects Office has compiled plans for such an elevator. The space elevator concept is a structure extending from the surface of the Earth to geostationary Earth orbit (GEO) at 35,786 km in altitude. The tower would be approximately 50 km tall with a cable tethered to the top. Its center mass would be at GEO such that the entire structure orbits the Earth in sync with the Earth's rotation maintaining a stationary position over its base attachment at the equator. Electromagnetic vehicles traveling along the cable could serve as a mass transportation system for transporting people, payloads, and power between space and Earth. This illustration by artist Pat Rawling shows the concept of a space elevator as viewed from the geostationary transfer station looking down the length of the elevator towards the Earth.
Dignam, Timothy A.; Evens, Anne; Eduardo, Eduard; Ramirez, Shokufeh M.; Caldwell, Kathleen L.; Kilpatrick, Nikki; Noonan, Gary P.; Flanders, W. Dana; Meyer, Pamela A.; McGeehin, Michael A.
2004-01-01
Objectives. We assessed the prevalence of elevated blood lead levels (≥ 10 micrograms of lead per deciliter of blood), risk factors, and previous blood lead testing among children in 2 high-risk Chicago, Ill, communities. Methods. Through high-intensity targeted screening, blood lead levels were tested and risks were assessed among a representative sample of children aged 1 to 5 years who were at risk for lead exposure. Results. Of the 539 children who were tested, 27% had elevated blood lead levels, and 61% had never been tested previously. Elevated blood lead levels were associated with chipped exterior house paint. Conclusions. Most of the children who lived in these communities—where the prevalence for elevated blood lead levels among children was 12 times higher than the national prevalence—were not tested for lead poisoning. Our findings highlight the need for targeted community outreach that includes testing blood lead levels in accordance with the American Academy of Pediatrics’ recommendations. PMID:15514235
Selby, Edward A; Kranzler, Amy; Panza, Emily; Fehling, Kara B
2016-04-01
Influenced by chaos theory, the emotional cascade model proposes that rumination and negative emotion may promote each other in a self-amplifying cycle that increases over time. Accordingly, exponential-compounding effects may better describe the relationship between rumination and negative emotion when they occur in impulsive persons, and predict impulsive behavior. Forty-seven community and undergraduate participants who reported frequent engagement in impulsive behaviors monitored their ruminative thoughts and negative emotion multiple times daily for two weeks using digital recording devices. Hypotheses were tested using cross-lagged mixed model analyses. Findings indicated that rumination predicted subsequent elevations in rumination that lasted over extended periods of time. Rumination and negative emotion predicted increased levels of each other at subsequent assessments, and exponential functions for these associations were supported. Results also supported a synergistic effect between rumination and negative emotion, predicting larger elevations in subsequent rumination and negative emotion than when one variable alone was elevated. Finally, there were synergistic effects of rumination and negative emotion in predicting number of impulsive behaviors subsequently reported. These findings are consistent with the emotional cascade model in suggesting that momentary rumination and negative emotion progressively propagate and magnify each other over time in impulsive people, promoting impulsive behavior. © 2014 Wiley Periodicals, Inc.
Geographic characteristics of sable (Martes zibellina) distribution over time in Northeast China.
Zhang, Rui; Yang, Li; Ai, Lin; Yang, Qiuyuan; Chen, Minhao; Li, Jingxi; Yang, Lei; Luan, Xiaofeng
2017-06-01
Understanding historical context can help clarify the ecological and biogeographic characteristics of species population changes. The sable ( Martes zibellina ) population has decreased dramatically in Northeast China since the l950s, and understanding the changes in its distribution over time is necessary to support conservation efforts. To achieve this goal, we integrated ecological niche modeling and historical records of sables to estimate the magnitude of change in their distribution over time. Our results revealed a 51.71% reduction in their distribution in 2000-2016 compared with the potential distribution in the 1950s. This reduction was related to climate change (Pearson's correlation: Bio1, -.962, p < .01; Bio2, -.962, p < .01; Bio5, .817, p < .05; Bio6, .847, p < .05) and human population size (-.956, p < .01). The sable population tended to migrate in different directions and elevations over time in different areas due to climate change: In the Greater Khingan Mountains, they moved northward and to lower elevations; in the Lesser Khingan Mountains, they moved northward; and in the Changbai Mountains, they move southward and to higher elevations. Active conservation strategies should be considered in locations where sable populations have migrated or may migrate to.
NASA Astrophysics Data System (ADS)
Ishihara, Miya; Arai, Tsunenori; Kikuchi, Makoto; Nakano, Hironori; Kawauchi, Satoko; Obara, Minoru
1998-05-01
We compared infrared radiation measurement with stress wave measurement for real-time ablation monitoring during photorefractive keratectomy (PRK). We estimated temperature elevation which may be one of the most effective parameter for PRK monitoring, because the ablation mechanism is mainly attributed to thermal kinetics. The temperature elevation of ablated cornea was evaluated by the infrared radiation and the stress wave. The thermal radiation from irradiated cornea was detected by a MCT detector. The measured signal increased sharply just after the laser irradiation and decreased quasi- exponentially. We could calculate the temperature elevation by observed signal using Stefan-Boltzmann radiation law. In the case of the gelatin gel (15% wt) ablation in vitro, the temperature elevation was 97 deg. at 208 mJ/cm2 in the laser fluence. We also measured transient stress wave by the acoustic transducer which was made by polyvinylidene fluoride (PVDF) film. The temperature elevation could be calculated from the peak stress amplitude based on the short pulsed laser ablation theory. The good agreement on the temperature elevation was obtained between the infrared and the stress based estimations. Due to non-contact and non-invasive method, our infrared measurements for temperature elevation monitoring may be available to accomplish the feedback control on the PRK.
Childbirth and symptoms of postpartum depression and anxiety: a prospective birth cohort study
Bell, A. F.; Carter, C. S.; Davis, J. M.; Golding, J.; Adejumo, O.; Pyra, M.; Connelly, J. J.; Rubin, L. H.
2016-01-01
We investigated associations between aspects of childbirth and elevated postpartum symptoms of depression and anxiety. We employed secondary analysis of perinatal data (N=4657–4946) from the Avon Longitudinal Study of Parents and Children (ALSPAC) birth cohort. Multivariable logistic regression models (adjusted for covariates) examined predictors of elevated symptoms of postpartum depression and anxiety. Predictors included the following: type of delivery (normal physiological vs. interventive non-physiological), immediate postpartum complications, and maternal perception of the recent birth experience. The Edinburgh Postnatal Depression Scale assessed elevated symptoms of depression (score≥13), and the Crown-Crisp Experiential Index assessed elevated symptoms of anxiety (score≥9) at 2 and 8 months after delivery. A more negative perception of the recent birth experience was associated with elevated symptoms of anxiety at 2 months [odds ratio (OR) 1.52, 95 % confidence interval (CI) 1.25–1.85] and 8 months (OR 1.30, 95 % CI 1.06–1.60) postpartum but was not associated with elevated symptoms of depression at either time point. Type of delivery (physiological vs. non-physiological) and immediate postpartum complications were not associated with elevated symptoms of depression or anxiety. Our findings suggest that improving women's childbirth experience may decrease the likelihood of postpartum anxiety, but not postpartum depression. PMID:26202722
Garbacea, Antoanela; Lozada, Jaime L; Church, Christopher A; Al-Ardah, Aladdin J; Seiberling, Kristin A; Naylor, W Patrick; Chen, Jung-Wei
2012-08-01
Transcrestal sinus membrane elevation is a surgical procedure performed to increase the bone volume in the maxillary sinus cavity. Because of visual limitations, the potential for maxillary sinus membrane perforations may be greater than with the lateral approach technique. The aim of this study was to macroscopically investigate ex vivo the occurrence of sinus membrane perforation during surgery using 3 transcrestal sinus floor elevation methods. Twenty fresh human cadaver heads, with 40 intact sinuses, were used for simultaneous sinus membrane elevation, placement of graft material, and dental implants. Real-time sinus endoscopy, periapical digital radiographs, and cone-beam computerized tomography (CBCT) images were subsequently used to evaluate the outcome of each surgical procedure. Perforation rates for each of the 3 techniques were then compared using a significance level of P < .05. No statistically significant differences in the perforation rate (P = .79) were found among the 3 surgical techniques. Although the sinus endoscope noted a higher frequency of perforations at the time of implant placement as compared with instrumentation or graft insertion, the difference was not statistically significant (P = .04). The CBCT readings were judged to be more accurate for identifying evidence of sinus perforations than the periapical radiographs when compared with the direct visualization with the endoscope. This pilot study demonstrated that a sinus membrane perforation can occur at any time during the sinus lift procedure, independent of the surgical method used.
Depressive symptoms and responses to cigarette pack warning labels among Mexican smokers
Thrasher, James F.; Cayir, Ebru; Hardin, James W.; Perez-Hernandez, Rosaura; Froeliger, Brett
2016-01-01
Objective we examine whether having depressive symptoms (DS) is associated with different responses to cigarette package health warning labels (HWLs) before and after the implementation of pictorial HWLs in Mexico. Methods we analyze data from adult smokers from Wave 4 and Wave 5 (n=1340) of the International Tobacco Control Policy Evaluation Project in Mexico. Seven CES-D items assessed DS, with scores ≥ 7 indicating elevated DS. Outcomes included: attention to HWLs; cognitive responses to HWLs; tobacco constituents awareness; putting off smoking due to HWLs; avoidance of HWLs; and awareness of telephone support for cessation (i.e., quitlines). Mixed effects models were used to assess main and interactive effects of DS and time (i.e., survey wave) on each outcome. Results all HWL responses increased over time, except putting off smoking. Statistically significant interactions were found between DS and time for models of tobacco constituents awareness (b=−0.36, SE= 0.15, p=.022); putting off smoking (OR=0.41, 95% CI 0.25, 0.66); avoidance of HWLs (OR=1.84, 95% 1.03, 3.29); and quitline awareness (OR=0.35, 95% CI 0.21, 0.56). Compared to smokers with low DS, smokers with elevated DS reported stronger HWL responses at baseline; however, HWL responses increased over time among smokers with low DS, whereas HWL responses showed little or no change among smokers with elevated DS. Discussion population-level increases in HWL responses after pictorial HWLs were introduced in Mexico appeared mostly limited to smokers with low DS. In general, however, smokers with elevated DS reported equivalent or stronger HWL responses than smokers with low DS. PMID:26867043
NASA Astrophysics Data System (ADS)
Kaplan, D.; Muñoz-Carpena, R.
2011-02-01
SummaryRestoration of degraded floodplain forests requires a robust understanding of surface water, groundwater, and vadose zone hydrology. Soil moisture is of particular importance for seed germination and seedling survival, but is difficult to monitor and often overlooked in wetland restoration studies. This research hypothesizes that the complex effects of surface water and shallow groundwater on the soil moisture dynamics of floodplain wetlands are spatially complementary. To test this hypothesis, 31 long-term (4-year) hydrological time series were collected in the floodplain of the Loxahatchee River (Florida, USA), where watershed modifications have led to reduced freshwater flow, altered hydroperiod and salinity, and a degraded ecosystem. Dynamic factor analysis (DFA), a time series dimension reduction technique, was applied to model temporal and spatial variation in 12 soil moisture time series as linear combinations of common trends (representing shared, but unexplained, variability) and explanatory variables (selected from 19 additional candidate hydrological time series). The resulting dynamic factor models yielded good predictions of observed soil moisture series (overall coefficient of efficiency = 0.90) by identifying surface water elevation, groundwater elevation, and net recharge (cumulative rainfall-cumulative evapotranspiration) as important explanatory variables. Strong and complementary linear relationships were found between floodplain elevation and surface water effects (slope = 0.72, R2 = 0.86, p < 0.001), and between elevation and groundwater effects (slope = -0.71, R2 = 0.71, p = 0.001), while the effect of net recharge was homogenous across the experimental transect (slope = 0.03, R2 = 0.05, p = 0.242). This study provides a quantitative insight into the spatial structure of groundwater and surface water effects on soil moisture that will be useful for refining monitoring plans and developing ecosystem restoration and management scenarios in degraded coastal floodplains.
Edge, Christopher B; Rollinson, Njal; Brooks, Ronald J; Congdon, Justin D; Iverson, John B; Janzen, Fredric J; Litzgus, Jacqueline D
2017-02-01
Life histories evolve in response to constraints on the time available for growth and development. Nesting date and its plasticity in response to spring temperature may therefore be important components of fitness in oviparous ectotherms near their northern range limit, as reproducing early provides more time for embryos to complete development before winter. We used data collected over several decades to compare air temperature and nest date plasticity in populations of painted turtles and snapping turtles from a relatively warm environment (southeastern Michigan) near the southern extent of the last glacial maximum to a relatively cool environment (central Ontario) near the northern extent of post-glacial recolonization. For painted turtles, population-level differences in reaction norm elevation for two phenological traits were consistent with adaptation to time constraints, but no differences in reaction norm slopes were observed. For snapping turtle populations, the difference in reaction norm elevation for a single phenological trait was in the opposite direction of what was expected under adaptation to time constraints, and no difference in reaction norm slope was observed. Finally, among-individual variation in individual plasticity for nesting date was detected only in the northern population of snapping turtles, suggesting that reaction norms are less canalized in this northern population. Overall, we observed evidence of phenological adaptation, and possibly maladaptation, to time constraints in long-lived reptiles. Where present, (mal)adaptation occurred by virtue of differences in reaction norm elevation, not reaction norm slope. Glacial history, generation time, and genetic constraint may all play an important role in the evolution of phenological timing and its plasticity in long-lived reptiles. © 2016 by the Ecological Society of America.
Satellite and Instrument Influences on ICESat Waveforms
NASA Astrophysics Data System (ADS)
Webb, C. E.; Urban, T. J.; Neuenschwander, A. L.; Gutierrez, R.; Schutz, B. E.
2007-12-01
The White Sands Space Harbor (WSSH) has served as the principal ground calibration site throughout the Ice, Cloud and land Elevation Satellite (ICESat) mission. The Center for Space Research (CSR) at the University of Texas at Austin continues to conduct various experiments designed to validate the timing, geolocation and geometric characteristics of individual laser footprints on the surface. In addition, two airborne lidar surveys of the calibration site and surrounding area were conducted during the mission, first in 2003 and again in 2007. Chosen for its limited surface roughness and topographic flatness, this area has been targeted 3-4 times in each of the 12 ICESat mapping campaigns to date, yielding a significant altimetry data set. The derived surface elevations are compared with those from the airborne lidar surveys, as well as those obtained by the Shuttle Radar Topography Mission (SRTM). Furthermore, the Geoscience Laser Altimetry System (GLAS) onboard ICESat records a digitized waveform for each laser pulse returned from the surface. The two methods currently used to fit such signals in ICESat data processing are examined and compared for the WSSH waveforms. The first fits up to two distinct Gaussians and provides a surface elevation at the location of the maximum peak. The second fits up to six overlapping Gaussians and provides a surface elevation at the centroid of the pulse. Observed differences in the reported elevations are discussed in terms of the satellite's off-nadir targeting geometry, the laser energy, and the skewness of the returned waveforms.
Surface Response to Regional Uplift of Madagascar Reveals Short Wavelength Dynamic Topography
NASA Astrophysics Data System (ADS)
Stephenson, S.; White, N.
2016-12-01
The physiography of Madagascar is characterized by high elevation but low relief topography with 42% of the landscape at an elevation grgeater than 500 m. Eocene marine limestones crop out at an elevation of 400 m, extensive low relief erosion surfaces capped by laterites occur at elevations of up to 2 km, and longitudinal river profiles are disequilibrated. Together, these observations suggest that Madagascar underwent regional uplift in Neogene times. Inverse modeling of drainage networks suggests that regional uplift is diachronous and has occurred on wavelengths of 1000 km. The existence of deeply incised river channels together with low-temperature thermochronologic measurements (i.e. AFT, AHe) implies that erosion occurred in response to regional Neogene uplift. Admittance analysis of long wavelength free-air gravity and topography shows that admittance, Z = 45 ± 5 mGal/km. The history of Neogene volcanism and a lack of significant tectonic shortening both suggest that uplift is dynamically supported. Here we present a suite of U-Th dates of emergent coral reef deposits from northern Madagascar, whose margins are sometimes considered `stable'. Elevation of these coeval coral reefs decreases from 7.2 m at the northern tip of Madagascar to sea level 100 km to the south. The existence of a spatial gradient suggests that differential vertical motions occurred during Late Quaternary times. These results raise significant questions about the reliability both of emergent coral reefs as global sea-level markers and the length-scale of variations in dynamic topography.
ST Elevation in AVR: When Time May Not Mean Muscle
2017-10-31
for Cardiovascular Angiography and Interventions (/) --1 m (/) ~ --1 ) • ::J CD z Q) 0 0... :J Q) I < (/) --1 ;a m ~ L..-. __ - c... disease in patients with non-ST-segment elevation acute coronary syndrome. Am J Cardiol 2011;107(4):495-500. • Smith SW. Updates on the electrocardiogram in acute coronary syndromes. Curr Emerg Hosp Med Rep 2012;1{1):43-52.
Jennifer D. Knoepp; Craig R. See; James M. Vose; Chelcy F. Miniat; James S. Clark
2018-01-01
The interactions of terrestrial C pools and fluxes with spatial and temporal variation in climate are not well understood. We conducted this study in the southern Appalachian Mountains where complex topography provides variability in temperature, precipitation, and forest communities. In 1990, we established five large plots across an elevation gradient...
The Encoding of Sound Source Elevation in the Human Auditory Cortex.
Trapeau, Régis; Schönwiesner, Marc
2018-03-28
Spatial hearing is a crucial capacity of the auditory system. While the encoding of horizontal sound direction has been extensively studied, very little is known about the representation of vertical sound direction in the auditory cortex. Using high-resolution fMRI, we measured voxelwise sound elevation tuning curves in human auditory cortex and show that sound elevation is represented by broad tuning functions preferring lower elevations as well as secondary narrow tuning functions preferring individual elevation directions. We changed the ear shape of participants (male and female) with silicone molds for several days. This manipulation reduced or abolished the ability to discriminate sound elevation and flattened cortical tuning curves. Tuning curves recovered their original shape as participants adapted to the modified ears and regained elevation perception over time. These findings suggest that the elevation tuning observed in low-level auditory cortex did not arise from the physical features of the stimuli but is contingent on experience with spectral cues and covaries with the change in perception. One explanation for this observation may be that the tuning in low-level auditory cortex underlies the subjective perception of sound elevation. SIGNIFICANCE STATEMENT This study addresses two fundamental questions about the brain representation of sensory stimuli: how the vertical spatial axis of auditory space is represented in the auditory cortex and whether low-level sensory cortex represents physical stimulus features or subjective perceptual attributes. Using high-resolution fMRI, we show that vertical sound direction is represented by broad tuning functions preferring lower elevations as well as secondary narrow tuning functions preferring individual elevation directions. In addition, we demonstrate that the shape of these tuning functions is contingent on experience with spectral cues and covaries with the change in perception, which may indicate that the tuning functions in low-level auditory cortex underlie the perceived elevation of a sound source. Copyright © 2018 the authors 0270-6474/18/383252-13$15.00/0.
NASA Astrophysics Data System (ADS)
Studinger, M.; Brunt, K. M.; Casey, K.; Medley, B.; Neumann, T.; Manizade, S.; Linkswiler, M. A.
2015-12-01
In order to produce a cross-calibrated long-term record of ice-surface elevation change for input into ice sheet models and mass balance studies it is necessary to "link the measurements made by airborne laser altimeters, satellite measurements of ICESat, ICESat-2, and CryoSat-2" [IceBridge Level 1 Science Requirements, 2012] and determine the biases and the spatial variations between radar altimeters and laser altimeters using different wavelengths. The convergence zones of all ICESat tracks (86°S) and all ICESat-2 and CryoSat-2 tracks (88°S) are in regions of relatively low accumulation, making them ideal for satellite altimetry calibration. In preparation for ICESat-2 validation, the IceBridge and ICESat-2 science teams have designed IceBridge data acquisitions around 86°S and 88°S. Several aspects need to be considered when comparing and combining elevation measurements from different radar and laser altimeters, including: a) foot print size and spatial sampling pattern; b) accuracy and precision of each data sets; c) varying signal penetration into the snow; and d) changes in geodetic reference frames over time, such as the International Terrestrial Reference Frame (ITRF). The presentation will focus on the analysis of several IceBridge flights around 86 and 88°S with the LVIS and ATM airborne laser altimeters and will evaluate the accuracy and precision of these data sets. To properly interpret the observed elevation change (dh/dt) as mass change, however, the various processes that control surface elevation fluctuations must be quantified and therefore future work will quantify the spatial variability in snow accumulation rates pole-ward of 86°S and in particular around 88°S. Our goal is to develop a cross-validated multi-sensor time series of surface elevation change pole-ward of 86°S that, in combination with measured accumulation rates, will support ICESat-2 calibration and validation and ice sheet mass balance studies.
Flowering responses of insect-pollinated plants to elevated CO{sub 2} levels
DOE Office of Scientific and Technical Information (OSTI.GOV)
Cushman, J.H.; Koch, G.W.; Chiariello, N.R.
1995-06-01
Elevated atmospheric CO{sub 2} concentrations have been predicted or shown to substantially influence plants, communities and ecosystems in a variety of ways. Here, we examined the effects of elevated CO{sub 2} levels on the timing and magnitude of flowering for two insect-pollinated annual plant species in a serpentine grassland. We focused on Lasthenia californica and Linanthus parviflorus and addressed three questions: (1) Do elevated CO{sub 2} levels influence flowering phenologies and is this species specific? (2) Do elevated CO{sub 2} levels affect flower production and is this due to altered numbers of individuals, flowers per plant, or both? and (3)more » Are effects on flowering due to elevated CO{sub 2} levels per se or changes in environmental conditions associated with methods used to manipulate CO{sub 2} levels? To address these questions, we used the ecosystem experiment at Stanford University`s Jasper Ridge Biological Preserve (San Mateo Co., CA). This system consists of 20 open-topped chambers - half receiving ambient CO{sub 2} (360 ppm) and half receiving elevated CO{sub 2} (720 ppm) - and 10 untreated plots serving as chamber controls. Results from the 1994 season demonstrated that there were species-specific responses to elevated CO{sub 2} levels and the field chambers. For Lasthenia californica, elevated CO{sub 2} per se did not affect relative abundance, inflorescence production, or phenology, but chambers did significantly increase inflorescence production and extend the duration of flowering. For Linanthus parviflorus, elevated CO{sub 2} levels significantly increased relative abundance and flower production, and extended the flowering period slightly, while the chambers significantly decreased flower production early in the season and increased it later in the season.« less
Cahoon, Donald R.; White, David A.; Lynch, James C.
2011-01-01
Crevasse splay environments provide a mesocosm for evaluating wetland formation and maintenance processes on a decadal time scale. Site elevation, water levels, vertical accretion, elevation change, shallow subsidence, and plant biomass were measured at five habitats along an elevation gradient to evaluate wetland formation and development in Brant Pass Splay; an active crevasse splay of the Balize delta of the Mississippi River. The processes of vertical development (vertical accretion, elevation change, and shallow subsidence) were measured with the surface elevation table–marker horizon method. There were three distinct stages to the accrual of elevation capital and wetland formation in the splay: sediment infilling, vegetative colonization, and development of a mature wetland community. Accretion, elevation gain, and shallow subsidence all decreased by an order of magnitude from the open water (lowest elevation) to the forest (highest elevation) habitats. Vegetative colonization occurred within the first growing season following emergence of the mud surface. An explosively high rate of below-ground production quickly stabilized the loosely consolidated sub-aerial sediments. After emergent vegetation colonization, vertical development slowed and maintenance of marsh elevation was driven both by sediment trapping by the vegetation and accumulation of plant organic matter in the soil. Continued vertical development and survival of the marsh then depended on the health and productivity of the plant community. The process of delta wetland formation is both complex and nonlinear. Determining the dynamics of wetland formation will help in understanding the processes driving the past building of the delta and in developing models for restoring degraded wetlands in the Mississippi River delta and other deltas around the world.
Riikonen, Johanna; Kontunen-Soppela, Sari; Ossipov, Vladimir; Tervahauta, Arja; Tuomainen, Marjo; Oksanen, Elina; Vapaavuori, Elina; Heinonen, Jaakko; Kivimäenpää, Minna
2012-09-01
Northern forests are currently experiencing increasing mean temperatures, especially during autumn and spring. Consequently, alterations in carbon sequestration, leaf biochemical quality and freezing tolerance (FT) are likely to occur. The interactive effects of elevated temperature and ozone (O(3)), the most harmful phytotoxic air pollutant, on Norway spruce (Picea abies (L.) Karst.) seedlings were studied by analysing phenology, metabolite concentrations in the needles, FT and gas exchange. Sampling was performed in September and May. The seedlings were exposed to a year-round elevated temperature (+1.3 °C), and to 1.4× ambient O(3) concentration during the growing season in the field. Elevated temperature increased the concentrations of amino acids, organic acids of the citric acid cycle and some carbohydrates, and reduced the concentrations of phenolic compounds, some organic acids of the shikimic acid pathway, sucrose, cyclitols and steroids, depending on the timing of the sampling. Although growth onset occurred earlier at elevated temperature, the temperature of 50% lethality (LT(50)) was similar in the treatments. Photosynthesis and the ratio of photosynthesis to dark respiration were reduced by elevated temperature. Elevated concentrations of O(3) reduced the total concentration of soluble sugars, and tended to reduce LT(50) of the needles in September. These results show that alterations in needle chemical quality can be expected at elevated temperatures, but the seedlings' sensitivity to autumn and spring frosts is not altered. Elevated O(3) has the potential to disturb cold hardening of Norway spruce seedlings in autumn, and to alter the water balance of the seedling through changes in stomatal conductance (g(s)), while elevated temperature is likely to reduce g(s) and consequently reduce the O(3)-flux inside the leaves.
NASA Astrophysics Data System (ADS)
Henebry, Geoffrey; Tomaszewska, Monika; Kelgenbaeva, Kamilya
2017-04-01
In the highlands of Kyrgyzstan, vertical transhumance is the foundation of montane agropastoralism. Terrain attributes, such as elevation, slope, and aspect, affect snow cover seasonality, which is a key influence on the timing of plant growth and forage availability. Our study areas include the highland pastures in Central Tien Shan mountains, specifically in the rayons of Naryn and At-Bashy in Naryn oblast, and Alay and Chong-Alay rayons in Osh oblast. To explore the linkages between snow cover seasonality and land surface phenology as modulated by terrain and variations in thermal time, we use 16 years (2001-2016) of Landsat surface reflectance data at 30 m resolution with MODIS land surface temperature and snow cover products at 1 km and 500 m resolution, respectively, and two digital elevation models, SRTM and ASTER GDEM. We model snow cover seasonality using frost degree-days and land surface phenology using growing degree-days as quadratic functions of thermal time: a convex quadratic (CxQ) model for land surface phenology and a concave quadratic (CvQ) model for snow cover seasonality. From the fitted parameter coefficients, we calculated phenometrics, including "peak height" and "thermal time to peak" for the CxQ models and "trough depth" and "thermal time to trough" for the CvQ models. We explore how these phenometrics change as a function of elevation and slope-aspect interactions and due to interannual variability. Further, we examine how snow cover duration and timing affects the subsequent peak height and thermal time to peak in wetter, drier, and normal years.
Hemolysis in a laminar flow-through Couette shearing device: an experimental study.
Boehning, Fiete; Mejia, Tzahiry; Schmitz-Rode, Thomas; Steinseifer, Ulrich
2014-09-01
Reducing hemolysis has been one of the major goals of rotary blood pump development and in the investigational phase, the capability of hemolysis estimation for areas of elevated shear stresses is valuable. The degree of hemolysis is determined by the amplitude of shear stress and the exposure time, but to date, the exact hemolytic behavior at elevated shear stresses and potential thresholds for subcritical shear exposure remain vague. This study provides experimental hemolysis data for a set of shear stresses and exposure times to allow better estimations of hemolysis for blood exposed to elevated shearing. Heparinized porcine blood with a hematocrit of 40% was mechanically damaged in a flow-through laminar Couette shear flow at a temperature of 23°C. Four levels of shear stress, 24, 592, 702, and 842 Pa, were replicated at two exposure times, 54 and 873 ms. For the calculation of the shear stresses, an apparent viscosity of 5 mPas was used, which was verified in an additional measurement of the blood viscosity. The hemolysis measurements were repeated four times, whereby all conditions were measured once within the same day and with blood from the same source. Samples were taken at the inlet and outlet of the shear region and an increase in plasma-free hemoglobin was measured. An index of hemolysis (IH) was thereby calculated giving the ratio of free to total hemoglobin. The results are compared with data from previously published studies using a similar shearing device. Hemolysis was found to increase exponentially with shear stress, but high standard deviations existed at measurements with elevated IH. At short exposure times, the IH remained low at under 0.5% for all shear stress levels. For high exposure times, the IH increased from 0.84% at 592 Pa up to 3.57% at the highest shear stress level. Hemolysis was significant for shear stresses above ∼600 Pa at the high exposure time of 873 ms. Copyright © 2014 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.
18 CFR 12.38 - Time for inspections and reports.
Code of Federal Regulations, 2011 CFR
2011-04-01
... reaches its normal maximum surface elevation, whichever occurs first. (3) For any development not set... information and analyses required by § 12.37(b). (c) Extension of time. For good cause shown, the Regional...
Rocker, Melissa M; Noonan, Sam; Humphrey, Craig; Moya, Aurelie; Willis, Bette L; Bay, Line K
2015-12-01
Declining health of scleractinian corals in response to deteriorating environmental conditions is widely acknowledged, however links between physiological and functional genomic responses of corals are less well understood. Here we explore growth and the expression of 20 target genes with putative roles in metabolism and calcification in the branching coral, Acropora millepora, in two separate experiments: 1) elevated pCO2 (464, 822, 1187 and 1638 μatm) and ambient temperature (27°C), and 2) elevated pCO2 (490 and 822 μatm) and temperature (28 and 31 °C). After 14 days of exposure to elevated pCO2 and ambient temperatures, no evidence of differential expression of either calcification or metabolism genes was detected between control and elevated pCO2 treatments. After 37 days of exposure to control and elevated pCO2, Ubiquinol-Cytochrome-C Reductase Subunit 2 gene (QCR2; a gene involved in complex III of the electron chain transport within the mitochondria and critical for generation of ATP) was significantly down-regulated in the elevated pCO2 treatment in both ambient and elevated temperature treatments. Overall, the general absence of a strong response to elevated pCO2 and temperature by the other 19 targeted calcification and metabolism genes suggests that corals may not be affected by these stressors on longer time scales (37 days). These results also highlight the potential for QCR2 to act as a biomarker of coral genomic responses to changing environments. Copyright © 2015 Elsevier B.V. All rights reserved.
Elevation Difference and Bouguer Anomaly Analysis Tool (EDBAAT) User's Guide
Smittle, Aaron M.; Shoberg, Thomas G.
2017-06-16
This report describes a software tool that imports gravity anomaly point data from the Gravity Database of the United States (GDUS) of the National Geospatial-Intelligence Agency and University of Texas at El Paso along with elevation data from The National Map (TNM) of the U.S. Geological Survey that lie within a user-specified geographic area of interest. Further, the tool integrates these two sets of data spatially and analyzes the consistency of the elevation of each gravity station from the GDUS with TNM elevation data; it also evaluates the consistency of gravity anomaly data within the GDUS data repository. The tool bins the GDUS data based on user-defined criteria of elevation misfit between the GDUS and TNM elevation data. It also provides users with a list of points from the GDUS data, which have Bouguer anomaly values that are considered outliers (two standard deviations or greater) with respect to other nearby GDUS anomaly data. “Nearby” can be defined by the user at time of execution. These outputs should allow users to quickly and efficiently choose which points from the GDUS would be most useful in reconnaissance studies or in augmenting and extending the range of individual gravity studies.
False elevation of carboxyhemoglobin: case report.
Mehrotra, Shruti; Edmonds, Marcia; Lim, Rodrick K
2011-02-01
Carbon monoxide toxicity in infants and children, like adults, produce nonspecific symptoms with normal vital signs necessitating the serum measurement of carboxyhemoglobin (COHb). In infants, the COHb may be falsely elevated. Our goal was to report a case of suspected carbon monoxide toxicity in an infant and the likely cause of the falsely elevated serum COHb. A previously healthy 3-month-old girl presented to the pediatric emergency department (ED) with smoke inhalation from a defective furnace. She was asymptomatic. On examination, she was alert, with Glasgow Coma Scale of 15 and normal vital signs. Cardiorespiratory and neurological examinations were completely normal. Because of concern regarding carbon monoxide poisoning, she was treated with normobaric oxygen therapy. Initial and subsequent serum COHb levels were persistently elevated, despite treatment and the infant appearing clinically well. As such, she had a prolonged stay in the ED. Further investigations found that fetal hemoglobin interferes with the spectrophotometric method used to analyze serum COHb levels. Carboxyhemoglobin serum level, in infants, may be falsely elevated due to the fetal hemoglobin interfering with standard methods of analysis. Knowledge of the false elevation using standard spectrophotometric methods of COHb in clinically well-appearing infants can decrease unnecessary oxygen therapy and monitoring time in the ED.
Feng, Youzhi; Lin, Xiangui; Yu, Yongchang; Zhu, Jianguo
2011-11-01
The knowledge of the impact of elevated ground-level O(3) below ground the agro-ecosystem is limited. A field experiment in China Ozone Free-Air Concentration Enrichment (FACE-O(3)) facility on a rice-wheat rotation system was carried out to investigate responses of anoxygenic phototrophic purple bacteria (AnPPB) to elevated ground-level O(3). AnPPB community structures and sizes in paddy soil were monitored by molecular approaches including PCR-DGGE and real-time quantitative PCR based upon the pufM gene on three typical rice growth stages. Repetitive sequence-based PCR (rep-PCR) in combination with culture-reliant method was conducted to reveal changes in genotypic diversity. Elevated ground-level O(3) statistically reduce AnPPB abundance and percentage in total bacterial community in flooded rice soil via decreasing their genotypic diversity and metabolic versatility. Concomitantly, their community composition changed after rice anthesis stage under elevated ground-level O(3). Our results from AnPPB potential responses imply that continuously elevated ground-level O(3) in the future would eventually harm the health of paddy ecosystem through negative effect on soil microorganisms.
NASA Astrophysics Data System (ADS)
Li, Xingxing; Ge, Maorong; Dai, Xiaolei; Ren, Xiaodong; Fritsche, Mathias; Wickert, Jens; Schuh, Harald
2015-06-01
In this contribution, we present a GPS+GLONASS+BeiDou+Galileo four-system model to fully exploit the observations of all these four navigation satellite systems for real-time precise orbit determination, clock estimation and positioning. A rigorous multi-GNSS analysis is performed to achieve the best possible consistency by processing the observations from different GNSS together in one common parameter estimation procedure. Meanwhile, an efficient multi-GNSS real-time precise positioning service system is designed and demonstrated by using the multi-GNSS Experiment, BeiDou Experimental Tracking Network, and International GNSS Service networks including stations all over the world. The statistical analysis of the 6-h predicted orbits show that the radial and cross root mean square (RMS) values are smaller than 10 cm for BeiDou and Galileo, and smaller than 5 cm for both GLONASS and GPS satellites, respectively. The RMS values of the clock differences between real-time and batch-processed solutions for GPS satellites are about 0.10 ns, while the RMS values for BeiDou, Galileo and GLONASS are 0.13, 0.13 and 0.14 ns, respectively. The addition of the BeiDou, Galileo and GLONASS systems to the standard GPS-only processing, reduces the convergence time almost by 70 %, while the positioning accuracy is improved by about 25 %. Some outliers in the GPS-only solutions vanish when multi-GNSS observations are processed simultaneous. The availability and reliability of GPS precise positioning decrease dramatically as the elevation cutoff increases. However, the accuracy of multi-GNSS precise point positioning (PPP) is hardly decreased and few centimeter are still achievable in the horizontal components even with 40 elevation cutoff. At 30 and 40 elevation cutoffs, the availability rates of GPS-only solution drop significantly to only around 70 and 40 %, respectively. However, multi-GNSS PPP can provide precise position estimates continuously (availability rate is more than 99.5 %) even up to 40 elevation cutoff (e.g., in urban canyons).
Bangsgaard Bendtsen, Katja Maria; Krych, Lukasz; Sørensen, Dorte Bratbo; Pang, Wanyong; Nielsen, Dennis Sandris; Josefsen, Knud; Hansen, Lars H; Sørensen, Søren J; Hansen, Axel Kornerup
2012-01-01
Stress has profound influence on the gastro-intestinal tract, the immune system and the behavior of the animal. In this study, the correlation between gut microbiota composition determined by Denaturing Grade Gel Electrophoresis (DGGE) and tag-encoded 16S rRNA gene amplicon pyrosequencing (454/FLX) and behavior in the Tripletest (Elevated Plus Maze, Light/Dark Box, and Open Field combined), the Tail Suspension Test, and Burrowing in 28 female BALB/c mice exposed to two weeks of grid floor induced stress was investigated. Cytokine and glucose levels were measured at baseline, during and after exposure to grid floor. Stressing the mice clearly changed the cecal microbiota as determined by both DGGE and pyrosequencing. Odoribacter, Alistipes and an unclassified genus from the Coriobacteriaceae family increased significantly in the grid floor housed mice. Compared to baseline, the mice exposed to grid floor housing changed the amount of time spent in the Elevated Plus Maze, in the Light/Dark Box, and burrowing behavior. The grid floor housed mice had significantly longer immobility duration in the Tail Suspension Test and increased their number of immobility episodes from baseline. Significant correlations were found between GM composition and IL-1α, IFN-γ, closed arm entries of Elevated Plus Maze, total time in Elevated Plus Maze, time spent in Light/Dark Box, and time spent in the inner zone of the Open Field as well as total time in the Open Field. Significant correlations were found to the levels of Firmicutes, e.g. various species of Ruminococccaceae and Lachnospiraceae. No significant difference was found for the evaluated cytokines, except an overall decrease in levels from baseline to end. A significant lower level of blood glucose was found in the grid floor housed mice, whereas the HbA1c level was significantly higher. It is concluded that grid floor housing changes the GM composition, which seems to influence certain anxiety-related parameters.
Pereira, M H C; Wiltbank, M C; Guida, T G; Lopes, F R; Vasconcelos, J L M
2017-10-01
Two treatments designed to increase circulating progesterone concentration (P4) during preovulatory follicle development were compared. One treatment used 2 intravaginal P4 implants (controlled internal drug-releasing inserts; CIDR) and the other used a GnRH treatment at beginning of the protocol. Lactating Holstein cows that had been diagnosed as nonpregnant were randomly assigned to receive timed artificial insemination (TAI) following 1 of 2 treatments (n = 1,638 breedings): (1) GnRH: CIDR+ 2 mg of estradiol (E2) benzoate + 100 µg of GnRH on d -11, PGF 2α on d -4, CIDR withdrawal + 1.0 mg of E2-cypionate + PGF 2α ) on d -2, and TAI on d 0; or (2) 2CIDR: 2 CIDR + 2 mg of E2-benzoate on d -11, 1 CIDR withdrawn + PGF 2α on d -4, second CIDR withdrawn + 1.0 mg of E2-cypionate + PGF 2α on d -2, and TAI on d 0. Milk yield was measured daily between d 0 and d 7. Rectal temperature was measured using a digital thermometer at d 0 and 7, and elevated body temperature was defined as an average rectal temperature ≥39.1°C. Pregnancy diagnoses were performed on d 32 and 60 after TAI. We detected no effect of treatments on pregnancy per AI or pregnancy loss regardless of elevated body temperature, body condition score, parity, milk yield, or presence or absence of a corpus luteum (CL) on d -11 or d -4. Pregnancy per AI at 60 d was reduced [elevated body temperature = 22.8% (162/709), no elevated body temperature 34.1% (279/817)] and pregnancy loss tended to increase [elevated body temperature = 20.2% (41/203), no elevated body temperature 14.4% (47/326)] in cows with elevated body temperature. Various physiological measurements associated with greater fertility were also reduced in cows with elevated body temperature, such as percentage of cows with a CL at PGF 2α (decreased 7.9%), ovulatory follicle diameter (decreased 0.51 mm), expression of estrus (decreased 5.1%), and ovulation near TAI (decreased 2.8%) compared with cows without elevated body temperature. A greater proportion of cows (30.2%) had a CL at PGF 2α in the GnRH treatment [74.1% (570/763)] than in the 2CIDR treatment [56.9% (434/763)]; however, circulating P4 concentration was greater at the time of PGF 2α treatment (d -4) for cows 2CIDR (4.26 ± 0.13 ng/mL) than in cows in GnRH (3.99 ± 0.14 ng/mL). Thus, these 2 protocols yield similar fertility results that might be due to somewhat different physiological alterations. Treatment with GnRH increased the proportion of cows with a CL at PGF 2α ; however, the 2CIDR protocol increased circulating P4 under all circumstances. Copyright © 2017 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Susong, D.; Marks, D.; Garen, D.
1999-01-01
Topographically distributed energy- and water-balance models can accurately simulate both the development and melting of a seasonal snowcover in the mountain basins. To do this they require time-series climate surfaces of air temperature, humidity, wind speed, precipitation, and solar and thermal radiation. If data are available, these parameters can be adequately estimated at time steps of one to three hours. Unfortunately, climate monitoring in mountain basins is very limited, and the full range of elevations and exposures that affect climate conditions, snow deposition, and melt is seldom sampled. Detailed time-series climate surfaces have been successfully developed using limited data and relatively simple methods. We present a synopsis of the tools and methods used to combine limited data with simple corrections for the topographic controls to generate high temporal resolution time-series images of these climate parameters. Methods used include simulations, elevational gradients, and detrended kriging. The generated climate surfaces are evaluated at points and spatially to determine if they are reasonable approximations of actual conditions. Recommendations are made for the addition of critical parameters and measurement sites into routine monitoring systems in mountain basins.Topographically distributed energy- and water-balance models can accurately simulate both the development and melting of a seasonal snowcover in the mountain basins. To do this they require time-series climate surfaces of air temperature, humidity, wind speed, precipitation, and solar and thermal radiation. If data are available, these parameters can be adequately estimated at time steps of one to three hours. Unfortunately, climate monitoring in mountain basins is very limited, and the full range of elevations and exposures that affect climate conditions, snow deposition, and melt is seldom sampled. Detailed time-series climate surfaces have been successfully developed using limited data and relatively simple methods. We present a synopsis of the tools and methods used to combine limited data with simple corrections for the topographic controls to generate high temporal resolution time-series images of these climate parameters. Methods used include simulations, elevational gradients, and detrended kriging. The generated climate surfaces are evaluated at points and spatially to determine if they are reasonable approximations of actual conditions. Recommendations are made for the addition of critical parameters and measurement sites into routine monitoring systems in mountain basins.
Exercise-induced rhabdomyolysis.
Lee, George
2014-11-03
Exercise-induced rhabdomyolysis, or exertional rhabdomyolysis (ER), is a clinical entity typically considered when someone presents with muscle stiffness, swelling, and pain out of proportion to the expected fatigue post exercise. The diagnosis is confirmed by myoglobinuria, and an elevated serum Creatinine Phosphokinase (CPK) level, usually 10 times the normal range. However, an elevation in CPK is seen in most forms of strenuous exercise, up to 20 times the upper normal range. Therefore, there is no definitive pathologic CPK cut-off. Fortunately the dreaded complication of acute renal failure is rare compared to other forms rhabdomyolysis. We review the risks, diagnosis, clinical course and treatment for exercise- induced rhabdomyolysis.
Telis, Pamela A.; Henkel, Heather
2009-01-01
The Everglades Depth Estimation Network (EDEN) is an integrated system of real-time water-level monitoring, ground-elevation data, and water-surface elevation modeling to provide scientists and water managers with current on-line water-depth information for the entire freshwater part of the greater Everglades. To assist users in applying the EDEN data to their particular needs, a series of five EDEN tools, or applications (EDENapps), were developed. Using EDEN's tools, scientists can view the EDEN datasets of daily water-level and ground elevations, compute and view daily water depth and hydroperiod surfaces, extract data for user-specified locations, plot transects of water level, and animate water-level transects over time. Also, users can retrieve data from the EDEN datasets for analysis and display in other analysis software programs. As scientists and managers attempt to restore the natural volume, timing, and distribution of sheetflow in the wetlands, such information is invaluable. Information analyzed and presented with these tools is used to advise policy makers, planners, and decision makers of the potential effects of water management and restoration scenarios on the natural resources of the Everglades.
ICESAT Laser Altimeter Pointing, Ranging and Timing Calibration from Integrated Residual Analysis
NASA Technical Reports Server (NTRS)
Luthcke, Scott B.; Rowlands, D. D.; Carabajal, C. C.; Harding, D. H.; Bufton, J. L.; Williams, T. A.
2003-01-01
On January 12, 2003 the Ice, Cloud and land Elevation Satellite (ICESat) was successfully placed into orbit. The ICESat mission carries the Geoscience Laser Altimeter System (GLAS), which has a primary measurement of short-pulse laser- ranging to the Earth s surface at 1064nm wavelength at a rate of 40 pulses per second. The instrument has collected precise elevation measurements of the ice sheets, sea ice roughness and thickness, ocean and land surface elevations and surface reflectivity. The accurate geolocation of GLAS s surface returns, the spots from which the laser energy reflects on the Earth s surface, is a critical issue in the scientific application of these data. Pointing, ranging, timing and orbit errors must be compensated to accurately geolocate the laser altimeter surface returns. Towards this end, the laser range observations can be fully exploited in an integrated residual analysis to accurately calibrate these geolocation/instrument parameters. ICESat laser altimeter data have been simultaneously processed as direct altimetry from ocean sweeps along with dynamic crossovers in order to calibrate pointing, ranging and timing. The calibration methodology and current calibration results are discussed along with future efforts.
NASA Technical Reports Server (NTRS)
Lutchke, Scott B.; Rowlands, David D.; Harding, David J.; Bufton, Jack L.; Carabajal, Claudia C.; Williams, Teresa A.
2003-01-01
On January 12, 2003 the Ice, Cloud and land Elevation Satellite (ICESat) was successfUlly placed into orbit. The ICESat mission carries the Geoscience Laser Altimeter System (GLAS), which consists of three near-infrared lasers that operate at 40 short pulses per second. The instrument has collected precise elevation measurements of the ice sheets, sea ice roughness and thickness, ocean and land surface elevations and surface reflectivity. The accurate geolocation of GLAS's surface returns, the spots from which the laser energy reflects on the Earth's surface, is a critical issue in the scientific application of these data Pointing, ranging, timing and orbit errors must be compensated to accurately geolocate the laser altimeter surface returns. Towards this end, the laser range observations can be fully exploited in an integrated residual analysis to accurately calibrate these geolocation/instrument parameters. Early mission ICESat data have been simultaneously processed as direct altimetry from ocean sweeps along with dynamic crossovers resulting in a preliminary calibration of laser pointing, ranging and timing. The calibration methodology and early mission analysis results are summarized in this paper along with future calibration activities
Advanced age, cardiovascular risk burden, and timed up and go test performance in Parkinson disease.
Kotagal, Vikas; Albin, Roger L; Müller, Martijn L T M; Koeppe, Robert A; Studenski, Stephanie; Frey, Kirk A; Bohnen, Nicolaas I
2014-12-01
Cardiovascular comorbidities are a known risk factor for impaired mobility in elderly individuals. Motor impairments in Parkinson disease are conventionally ascribed to nigrostriatal dopaminergic denervation although progressive gait and balance impairments become more common with aging and often show limited response to dopaminergic replacement therapies. We explored the association between elevated cardiovascular risk factors and performance on the Timed Up and Go test in cross-sectional of Parkinson disease subjects (n = 83). Cardiovascular risk factor status was estimated using the Framingham General Cardiovascular Disease risk-scoring algorithm in order to dichotomize the cohort into those with and without elevated modifiable cardiovascular risk compared with normative scores for age and gender. All subjects underwent clinical and neuroimaging evaluations including a 3-m Timed Up and Go test, [(11)C]dihydrotetrabenazine positron emission tomography imaging to estimate nigrostriatal dopamine terminal loss, and an magnetic resonance imaging assessment of leukoaraiosis. A similar analysis was performed in 49 healthy controls. After adjusting for disease duration, leukoaraiosis, and nigrostriatal dopaminergic denervation, Parkinson disease subjects with elevated Framingham risk scores (n = 61) displayed slower Timed Up and Go test performance (β = 1.86, t = 2.41, p = .018) compared with subjects with normal range Framingham risk scores (n = 22). When age ≥65 was added to the model in a post hoc analysis, the strength of effect seen with older age (β = 1.51, t = 2.44, p = .017) was similar to that of elevated Framingham risk scoring (β = 1.87, t = 2.51, p = .014). In a multivariable regression model studying the healthy control population, advanced age (t = 2.15, p = .037) was a significant predictor of Timed Up and Go speed though striatal [(11)C]dihydrotetrabenazine (t = -1.30, p = .19) and elevated Framingham risk scores (t = 1.32, p = .19) were not. Modifiable cardiovascular risk factors and older age may independently exacerbate balance-related disability in Parkinson disease and may exert additive or synergistic pathological effects. The pathophysiology of these impairments cannot be explained completely by nigrostriatal dopaminergic denervation or leukoaraiosis burden and may relate to systemic factors seen with accelerated aging. © The Author 2014. Published by Oxford University Press on behalf of The Gerontological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.
Abdulkareem, Omar A.; Abdullah, Mohd Mustafa Al Bakri; Hussin, Kamarudin; Ismail, Khairul Nizar; Binhussain, Mohammed
2013-01-01
This paper presents the mechanical and microstructural characteristics of a lightweight aggregate geopolymer concrete (LWAGC) synthesized by the alkali-activation of a fly ash source (FA) before and after being exposed to elevated temperatures, ranging from 100 to 800 °C. The results show that the LWAGC unexposed to the elevated temperatures possesses a good strength-to-weight ratio compared with other LWAGCs available in the published literature. The unexposed LWAGC also shows an excellent strength development versus aging times, up to 365 days. For the exposed LWAGC to the elevated temperatures of 100 to 800 °C, the results illustrate that the concretes gain compressive strength after being exposed to elevated temperatures of 100, 200 and 300 °C. Afterward, the strength of the LWAGC started to deteriorate and decrease after being exposed to elevated temperatures of 400 °C, and up to 800 °C. Based on the mechanical strength results of the exposed LWAGCs to elevated temperatures of 100 °C to 800 °C, the relationship between the exposure temperature and the obtained residual compressive strength is statistically analyzed and achieved. In addition, the microstructure investigation of the unexposed LWAGC shows a good bonding between aggregate and mortar at the interface transition zone (ITZ). However, this bonding is subjected to deterioration as the LWAGC is exposed to elevated temperatures of 400, 600 and 800 °C by increasing the microcrack content and swelling of the unreacted silicates. PMID:28788339
Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.; ...
2017-02-08
Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively. Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers. Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forestmore » and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine. Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.
Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively. Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers. Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forestmore » and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine. Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.« less
Characterization of the rat exploratory behavior in the elevated plus-maze with Markov chains.
Tejada, Julián; Bosco, Geraldine G; Morato, Silvio; Roque, Antonio C
2010-11-30
The elevated plus-maze is an animal model of anxiety used to study the effect of different drugs on the behavior of the animal. It consists of a plus-shaped maze with two open and two closed arms elevated 50cm from the floor. The standard measures used to characterize exploratory behavior in the elevated plus-maze are the time spent and the number of entries in the open arms. In this work, we use Markov chains to characterize the exploratory behavior of the rat in the elevated plus-maze under three different conditions: normal and under the effects of anxiogenic and anxiolytic drugs. The spatial structure of the elevated plus-maze is divided into squares, which are associated with states of a Markov chain. By counting the frequencies of transitions between states during 5-min sessions in the elevated plus-maze, we constructed stochastic matrices for the three conditions studied. The stochastic matrices show specific patterns, which correspond to the observed behaviors of the rat under the three different conditions. For the control group, the stochastic matrix shows a clear preference for places in the closed arms. This preference is enhanced for the anxiogenic group. For the anxiolytic group, the stochastic matrix shows a pattern similar to a random walk. Our results suggest that Markov chains can be used together with the standard measures to characterize the rat behavior in the elevated plus-maze. Copyright © 2010 Elsevier B.V. All rights reserved.
Conlisk, Erin; Castanha, Cristina; Germino, Matthew J.; Veblen, Thomas T; Smith, Jeremy M.; Kueppers, Lara M.
2017-01-01
Species distribution shifts in response to climate change require that recruitment increase beyond current range boundaries. For trees with long life spans, the importance of climate-sensitive seedling establishment to the pace of range shifts has not been demonstrated quantitatively.Using spatially explicit, stochastic population models combined with data from long-term forest surveys, we explored whether the climate-sensitivity of recruitment observed in climate manipulation experiments was sufficient to alter populations and elevation ranges of two widely distributed, high-elevation North American conifers.Empirically observed, warming-driven declines in recruitment led to rapid modelled population declines at the low-elevation, ‘warm edge’ of subalpine forest and slow emergence of populations beyond the high-elevation, ‘cool edge’. Because population declines in the forest occurred much faster than population emergence in the alpine, we observed range contraction for both species. For Engelmann spruce, this contraction was permanent over the modelled time horizon, even in the presence of increased moisture. For limber pine, lower sensitivity to warming may facilitate persistence at low elevations – especially in the presence of increased moisture – and rapid establishment above tree line, and, ultimately, expansion into the alpine.Synthesis. Assuming 21st century warming and no additional moisture, population dynamics in high-elevation forests led to transient range contractions for limber pine and potentially permanent range contractions for Engelmann spruce. Thus, limitations to seedling recruitment with warming can constrain the pace of subalpine tree range shifts.
Abdulkareem, Omar A; Abdullah, Mohd Mustafa Al Bakri; Hussin, Kamarudin; Ismail, Khairul Nizar; Binhussain, Mohammed
2013-10-09
This paper presents the mechanical and microstructural characteristics of a lightweight aggregate geopolymer concrete (LWAGC) synthesized by the alkali-activation of a fly ash source (FA) before and after being exposed to elevated temperatures, ranging from 100 to 800 °C. The results show that the LWAGC unexposed to the elevated temperatures possesses a good strength-to-weight ratio compared with other LWAGCs available in the published literature. The unexposed LWAGC also shows an excellent strength development versus aging times, up to 365 days. For the exposed LWAGC to the elevated temperatures of 100 to 800 °C, the results illustrate that the concretes gain compressive strength after being exposed to elevated temperatures of 100, 200 and 300 °C. Afterward, the strength of the LWAGC started to deteriorate and decrease after being exposed to elevated temperatures of 400 °C, and up to 800 °C. Based on the mechanical strength results of the exposed LWAGCs to elevated temperatures of 100 °C to 800 °C, the relationship between the exposure temperature and the obtained residual compressive strength is statistically analyzed and achieved. In addition, the microstructure investigation of the unexposed LWAGC shows a good bonding between aggregate and mortar at the interface transition zone (ITZ). However, this bonding is subjected to deterioration as the LWAGC is exposed to elevated temperatures of 400, 600 and 800 °C by increasing the microcrack content and swelling of the unreacted silicates.
NASA Astrophysics Data System (ADS)
Kapotis, Efstratios; Kalkanis, George
2016-10-01
According to the principle of equivalence, it is impossible to distinguish between gravity and inertial forces that a noninertial observer experiences in his own frame of reference. For example, let's consider an elevator in space that is being accelerated in one direction. An observer inside it would feel as if there was gravity force pulling him toward the opposite direction. The same holds for a person in a stationary elevator located in Earth's gravitational field. No experiment enables us to distinguish between the accelerating elevator in space and the motionless elevator near Earth's surface. Strictly speaking, when the gravitational field is non-uniform (like Earth's), the equivalence principle holds only for experiments in elevators that are small enough and that take place over a short enough period of time (Fig. 1). However, performing an experiment in an elevator in space is impractical. On the other hand, it is easy to combine both forces on the same observer, i.e., gravity and a fictitious inertial force due to acceleration. Imagine an observer in an elevator that falls freely within Earth's gravitational field. The observer experiences gravity pulling him down while it might be said that the inertial force due to gravity acceleration g pulls him up. Gravity and inertial force cancel each other, (mis)leading the observer to believe there is no gravitational field. This study outlines our implementation of a self-construction idea that we have found useful in teaching introductory physics students (undergraduate, non-majors).
Anyamba, Assaf; Linthicum, Kenneth J.; Small, Jennifer; Britch, Seth C.; Pak, Edwin; de La Rocque, Stephane; Formenty, Pierre; Hightower, Allen W.; Breiman, Robert F.; Chretien, Jean-Paul; Tucker, Compton J.; Schnabel, David; Sang, Rosemary; Haagsma, Karl; Latham, Mark; Lewandowski, Henry B.; Magdi, Salih Osman; Mohamed, Mohamed Ally; Nguku, Patrick M.; Reynes, Jean-Marc; Swanepoel, Robert
2010-01-01
Historical outbreaks of Rift Valley fever (RVF) since the early 1950s have been associated with cyclical patterns of the El Niño/Southern Oscillation (ENSO) phenomenon, which results in elevated and widespread rainfall over the RVF endemic areas of Africa. Using satellite measurements of global and regional elevated sea surface temperatures, elevated rainfall, and satellite derived-normalized difference vegetation index data, we predicted with lead times of 2–4 months areas where outbreaks of RVF in humans and animals were expected and occurred in the Horn of Africa, Sudan, and Southern Africa at different time periods from September 2006 to March 2008. Predictions were confirmed by entomological field investigations of virus activity and by reported cases of RVF in human and livestock populations. This represents the first series of prospective predictions of RVF outbreaks and provides a baseline for improved early warning, control, response planning, and mitigation into the future. PMID:20682905
Type A Aortic Dissection Presenting with Inferior ST-Elevation Myocardial Infarction.
Wu, Bao-Tzung; Li, Chun-Yi; Chen, Ying-Tsung
2014-05-01
Type A aortic dissection with concurrent ST-elevation myocardial infarction (STEMI) is relatively rare. However, it can be potentially fatal and easily misdiagnosed as STEMI alone. Misdiagnosis will lead to inappropriate administration of anticoagulant and thrombolytic therapy and delayed surgical repair of the aorta. In patients with STEMI, short reperfusion time is associated with improved survival, and minimizing the door-to-balloon time is the goal of therapy worldwide. However, signs critical for differential diagnosis may be overlooked in the rush to primary percutaneous coronary intervention. When a patient is encountered who presents with chest pain and ST elevation on electrocardiogram, STEMI should not be the only diagnosis considered. By using bedside available information, detailed history taking and focused physical examination, it is possible to avoid a mistaken diagnosis. Here we report a case of Stanford type A aortic dissection with STEMI that was initially misdiagnosed as sole acute inferior wall myocardial infarction. Patient mortality may have resulted from delayed diagnosis and surgical treatment. Acute myocardial infarction; Aortic dissection.
ICESat Observations of Arctic Sea Ice: A First Look
NASA Technical Reports Server (NTRS)
Kwok, Ron; Zwally, H. Jay; Yi, Dong-Hui
2004-01-01
Analysis of near-coincident ICESat and RADARSAT imagery shows that the retrieved elevations from the laser altimeter are sensitive to new openings (containing thin ice or open water) in the sea ice cover as well as to surface relief of old and first-year ice. The precision of the elevation estimates, measured over relatively flat sea ice, is approx. 2 cm Using the thickness of thin-ice in recent openings to estimate sea level references, we obtain the sea-ice free-board along the altimeter tracks. This step is necessitated by the large uncertainties in the time-varying sea surface topography compared to that required for accurate determination of free-board. Unknown snow depth introduces the largest uncertainty in the conversion of free-board to ice thickness. Surface roughness is also derived, for the first time, from the variability of successive elevation estimates along the altimeter track Overall, these ICESat measurements provide an unprecedented view of the Arctic Ocean ice cover at length scales at and above the spatial dimension of the altimeter footprint.
A tide prediction and tide height control system for laboratory mesocosms
Long, Jeremy D.
2015-01-01
Experimental mesocosm studies of rocky shore and estuarine intertidal systems may benefit from the application of natural tide cycles to better replicate variation in immersion time, water depth, and attendant fluctuations in abiotic and edaphic conditions. Here we describe a stand-alone microcontroller tide prediction open-source software program, coupled with a mechanical tidal elevation control system, which allows continuous adjustment of aquarium water depths in synchrony with local tide cycles. We used this system to monitor the growth of Spartina foliosa marsh cordgrass and scale insect herbivores at three simulated shore elevations in laboratory mesocosms. Plant growth decreased with increasing shore elevation, while scale insect population growth on the plants was not strongly affected by immersion time. This system shows promise for a range of laboratory mesocosm studies where natural tide cycling could impact organism performance or behavior, while the tide prediction system could additionally be utilized in field experiments where treatments need to be applied at certain stages of the tide cycle. PMID:26623195
Time Spent on the Internet and Adolescent Blood Pressure.
Cassidy-Bushrow, Andrea E; Johnson, Dayna A; Peters, Rosalind M; Burmeister, Charlotte; Joseph, Christine L M
2015-10-01
Internet use is nearly ubiquitous among adolescents. Growing evidence suggests heavy Internet use negatively impacts health, yet the relationship between time spent on the Internet and adolescent blood pressure (BP) is unknown. We examined the association between Internet use and elevated BP in a racially diverse cross-sectional sample of 331 healthy adolescents (ages 14-17 years). Heavy Internet use was defined as ≥ 2 hr/day, moderate use as <2 hr/day and ≥ 5 days/week, and light use as < 2 hr/day and ≤ 4 days/week. Elevated BP was defined as systolic or diastolic BP ≥ 90 th percentile. Heavy Internet users had statistically significantly higher odds of elevated BP compared to light Internet users. School nurses can play an important role in preventing high BP through assessment of BP and other health behaviors including Internet use, and health teaching to individuals, student groups, faculty, and parents to increase awareness of the relationship between Internet use and health. © The Author(s) 2014.
Ling, C. R.; Foster, M. A.; Mallard, J. R.
1979-01-01
In separate experiments, normal foreign tissue and malignant tumour were implanted s.c. into the rat thigh. NMR T1 values of the adjacent normal muscle, resulting from local inflammatory reactions or from malignant invasion, were measured. Elevations in T1 of the underlying muscle occurred within 24 h in both experiments, and it is believed these were caused by rapid inflammatory and immunological reactions to the implants. However the T1 values of muscle samples adjacent to the non-malignant implants decreased during the 11 days after implantation, dropping to values within the normal range. In the second experiment there was progressive malignant invasion into the normal adjacent tissue and the elevated T1 values were maintained throughout the 12-day period. The effects of the implantation on tissue water content are discussed in relation to NMR T1 relaxation times, and the relevance to whole-body NMR imaging of elevated T1 values due to nonmalignant pathological states is considered. PMID:526431
Force, acceleration and velocity during trampoline jumps—a challenging assignment
NASA Astrophysics Data System (ADS)
Pendrill, Ann-Marie; Ouattara, Lassana
2017-11-01
Bouncing on a trampoline lets the jumper experience the interplay between weightlessness and large forces on the body, as the motion changes between free fall and large acceleration in contact with the trampoline bed. In this work, several groups of students were asked to draw graphs of elevation, velocity and acceleration as a function of time, for two full jumps of the 2012 Olympic gold medal trampoline routine by Rosannagh MacLennan. We hoped that earlier kinaesthetic experiences of trampoline bouncing would help students make connections between the mathematical descriptions of elevation, velocity and acceleration, which is known to be challenging. However, very few of the student responses made reference to personal experiences of forces during bouncing. Most of the responses could be grouped into a few categories, which are presented and discussed in the paper. Although the time dependence of elevation was drawn relatively correctly in most cases, many of the graphs of velocity and acceleration display a lack of understanding of the relation between these different aspects of motion.
Optimization of motion control laws for tether crawler or elevator systems
NASA Technical Reports Server (NTRS)
Swenson, Frank R.; Von Tiesenhausen, Georg
1988-01-01
Based on the proposal of a motion control law by Lorenzini (1987), a method is developed for optimizing motion control laws for tether crawler or elevator systems in terms of the performance measures of travel time, the smoothness of acceleration and deceleration, and the maximum values of velocity and acceleration. The Lorenzini motion control law, based on powers of the hyperbolic tangent function, is modified by the addition of a constant-velocity section, and this modified function is then optimized by parameter selections to minimize the peak acceleration value for a selected travel time or to minimize travel time for the selected peak values of velocity and acceleration. It is shown that the addition of a constant-velocity segment permits further optimization of the motion control law performance.
2004-03-01
elevated temperature of 550 C. Cyclic loading of C/SiC was investigated at frequencies of 375 Hz , 10 Hz, 1 Hz, and 0.1 Hz. Creep-Rupture tests and tests that...is reduced when frequency of fatigue is increased. At high frequency fatigue (10Hz to 375 Hz ), C/SiC composites have longer cycle lives and time lives
60. Interior view, passage, north elevation. Though made larger over ...
60. Interior view, passage, north elevation. Though made larger over time, this circulation space was present since the house's earliest manifestation. The attic stair and closet date from phase II construction (After the mid-1740's). Similarly to the study chamber, the closet on the right was fitted into a former exterior window opening. - John Bartram House & Garden, House, 54th Street & Lindbergh Boulevard, Philadelphia, Philadelphia County, PA
William B. Leak; Mariko Yamasaki
2010-01-01
Remeasurements over a 70-year period (1931-1932 to 2002-2003) on 404 cruise plots on the Bartlett Experimental Forest in New Hampshire provided a record of landscape-level changes in the composition of overstory species over time by elevation and d.b.h. (diameter at breast height) classes. Typically, early to midsuccessional species declined while late successional...
Effect of horizontal pick and place locations on shoulder kinematics.
Könemann, R; Bosch, T; Kingma, I; Van Dieën, J H; De Looze, M P
2015-01-01
In this study the effects of horizontal bin locations in an order picking workstation on upper arm elevation, trunk inclination and hand use were investigated. Eight subjects moved (self-paced) light or heavy products (0.2 and 3.0 kg) from a central product bin to an inner or outer order bin (at 60 or 150 cm) on the left or right side of the workstation, while movements were recorded. The outer compared to inner bin location resulted in more upper arm elevation and trunk inclination per work cycle, both in terms of number of peak values and in terms of time integrals of angles (which is a dose measure over time). Considering the peak values and time integrals per minute (instead of per work cycle), these effects are reduced, due to the higher cycle times for outer bins. Hand use (left, right or both) was not affected by order bin locations.
Time Series of Greenland Ice-Sheet Elevations and Mass Changes from ICESat 2003-2009
NASA Astrophysics Data System (ADS)
Zwally, H. J.; Li, J.; Medley, B.; Robbins, J. W.; Yi, D.
2015-12-01
We follow the repeat-track analysis (RTA) of ICESat surface-elevation data by a second stage that adjusts the measured elevations on repeat passes to the reference track taking into account the cross-track slope (αc), in order to construct elevation time series. αc are obtained from RTA simultaneous solutions for αc, dh/dt, and h0. The height measurements on repeat tracks are initially interpolated to uniform along-track reference points (every 172 m) and times (ti) giving the h(xi,ti) used in the RTA solutions. The xi are the cross-track spacings from the reference track and i is the laser campaign index. The adjusted elevation measurements at the along-track reference points are hr(ti) = h(xi,ti) - xi tan(αc) - h0. The hr(ti) time series are averaged over 50 km cells creating H(ti) series and further averaged (weighted by cell area) to H(t) time series over drainage systems (DS), elevation bands, regions, and the entire ice sheet. Temperature-driven changes in the rate of firn compaction, CT(t), are calculated for 50 km cells with our firn-compaction model giving I(t) = H(t) - CT(t) - B(t) where B(t) is the vertical motion of the bedrock. During 2003 to 2009, the average dCT(t)/dt in the accumulation zone is -5 cm/yr, which amounts to a -75 km3/yr correction to ice volume change estimates. The I(t) are especially useful for studying the seasonal cycle of mass gains and losses and interannual variations. The H(t) for the ablation zone are fitted with a multi-variate function with a linear component describing the upward component of ice flow plus winter accumulation (fall through spring) and a portion of a sine function describing the superimposed summer melting. During fall to spring the H(t) indicate that the upward motion of the ice flow is at a rate of 1 m/yr, giving an annual mass gain of 180 Gt/yr in the ablation zone. The summer loss from surface melting in the high-melt summer of 2005 is 350 Gt/yr, giving a net surface loss of 170 Gt/yr from the ablation zone for 2005. During 2003-2008, the H(t) for the ablation zone show accelerations of the mass losses in the northwest DS8 and in the west-central DS7 (including Jacobshavn glacier) and offsetting decelerations of the mass losses in the east-central DS3 and southeast DS4, much of which occurred in 2008 possibly due to an eastward shift in the surface mass balance.
NASA Astrophysics Data System (ADS)
Loomis, S. E.; Russell, J. M.; Kelly, M. A.; Eggermont, H.; Verschuren, D.
2013-12-01
Tropical lapse rate variability on glacial/interglacial time scales has been hotly debated since the publication of CLIMAP in 1976. Low-elevation paleotemperature reconstructions from the tropics have repeatedly shown less warming from the Last Glacial Maximum (LGM) to present than reconstructions from high elevations, leading to widespread difficulty in estimating the true LGM-present temperature change in the tropics. This debate is further complicated by the fact that most paleotemperature estimates from high elevations in the tropics are derived from pollen- and moraine-based reconstructions of altitudinal shifts in vegetation belts and glacial equilibrium line altitudes (ELAs). These traditional approaches rely on the assumption that lapse rates have remained constant through time. However, this assumption is problematic in the case of the LGM, when pervasive tropical aridity most likely led to substantial changes in lapse rates. Glycerol dialkyl glycerol tetraethers (GDGTs) can be used to reconstruct paleotemperatures independent of hydrological changes, making them the ideal proxy to reconstruct high elevation temperature change and assess lapse rate variability through time. Here we present two new equatorial paleotemperature records from high elevations in East Africa (Lake Rutundu, Mt. Kenya and Lake Mahoma, Rwenzori Mountains, Uganda) based on branched GDGTs. Our record from Lake Rutundu shows deglacial warming starting near 17 ka and a mid-Holocene thermal maximum near 5 ka. The overall amplitude of warming in the Lake Rutundu record is 6.8×1.0°C from the LGM to the present, with mid-Holocene temperatures 1.6×0.9°C warmer than modern. Our record from Lake Mahoma extends back to 7 ka and shows similar temperature trends to our record from Lake Rutundu, indicating similar temporal resolution of high-elevation temperature change throughout the region. Combining these new records with three previously published GDGT temperature records from different elevations in East Africa (Sacred Lake, Lake Tanganyika, and Lake Malawi), we are able to reconstruct a continuous record of lapse rates and freezing level heights (FLHs) back to the LGM. We find that tropical lapse rates have varied widely over the last 22 ky, with the largest (lowest) lapse rate (FLH) around the LGM, while the smallest (highest) lapse rate (FLH) occurs during the mid-Holocene, confirming the amplification of warming at high altitudes between the LGM and present. These lapse rate and FLH reconstructions match records of regional hydrological variability, confirming the importance of glacial/interglacial humidity variations on altitudinal temperature gradients in the tropics. Furthermore, the FLH record largely matches records of tropical glacier ELA changes, indicating that warming from LGM-present was likely amplified at high altitudes throughout the tropics.
A plant distribution shift: temperature, drought or past disturbance?
Schwilk, Dylan W.; Keeley, Jon E.
2012-01-01
Simple models of plant response to warming climates predict vegetation moving to cooler and/or wetter locations: in mountainous regions shifting upslope. However, species-specific responses to climate change are likely to be much more complex. We re-examined a recently reported vegetation shift in the Santa Rosa Mountains, California, to better understand the mechanisms behind the reported shift of a plant distribution upslope. We focused on five elevational zones near the center of the gradient that captured many of the reported shifts and which are dominated by fire-prone chaparral. Using growth rings, we determined that a major assumption of the previous work was wrong: past fire histories differed among elevations. To examine the potential effect that this difference might have on the reported upward shift, we focused on one species, Ceanothus greggii: a shrub that only recruits post-fire from a soil stored seedbank. For five elevations used in the prior study, we calculated time series of past per-capita mortality rates by counting growth rings on live and dead individuals. We tested three alternative hypotheses explaining the past patterns of mortality: 1) mortality increased over time consistent with climate warming, 2) mortality was correlated with drought indices, and 3) mortality peaked 40–50 years post fire at each site, consistent with self-thinning. We found that the sites were different ages since the last fire, and that the reported increase in the mean elevation of C. greggii was due to higher recent mortality at the lower elevations, which were younger sites. The time-series pattern of mortality was best explained by the self-thinning hypothesis and poorly explained by gradual warming or drought. At least for this species, the reported distribution shift appears to be an artifact of disturbance history and is not evidence of a climate warming effect.
Skinner, John P.; Tuomi, Pam A.; Mellish, Jo-Ann E.
2015-01-01
The Steller sea lion, Eumetopias jubatus, has experienced regionally divergent population trends over recent decades. One potential mechanism for this disparity is that local factors cause reduced health and, therefore, reduced survival of individuals. The use of blood parameters to assess sea lion health may help to identify whether malnutrition, disease and stress are important drivers of current trends, but such assessments require species-specific knowledge of how parameters respond to various health challenges. We used principal components analysis to identify which key blood parameters (principal analytes) best described changes in health for temporarily captive juvenile Steller sea lions in known conditions. Generalized additive mixed models were used to estimate the changes in principal analytes with food intake, time in captivity and acute trauma associated with hot-iron branding and transmitter implant surgery. Of the 17 blood parameters examined, physiological changes for juvenile sea lions were best described using the following six principal analytes: red blood cell counts, white blood cell counts, globulin, platelets, glucose and total bilirubin. The white blood cell counts and total bilirubin declined over time in captivity, whereas globulin increased. Elevated red blood cell counts, white blood cell counts and total bilirubin and reduced globulin values were associated with lower food intake. After branding, white blood cell counts were elevated for the first 30 days, while globulin and platelets were elevated for the first 15 days only. After implant surgery, red blood cell counts and globulin remained elevated for 30 days, while white blood cell counts remained elevated during the first 15 days only. Glucose was unassociated with the factors we studied. These results were used to provide expected ranges for principal analytes at different levels of food intake and in response to the physical challenges of branding and implant surgery. These results provide a more detailed reference for future evaluations of health-related assessments. PMID:27293693
Evidence of exceptional oyster-reef resilience to fluctuations in sea level.
Ridge, Justin T; Rodriguez, Antonio B; Fodrie, F Joel
2017-12-01
Ecosystems at the land-sea interface are vulnerable to rising sea level. Intertidal habitats must maintain their surface elevations with respect to sea level to persist via vertical growth or landward retreat, but projected rates of sea-level rise may exceed the accretion rates of many biogenic habitats. While considerable attention is focused on climate change over centennial timescales, relative sea level also fluctuates dramatically (10-30 cm) over month-to-year timescales due to interacting oceanic and atmospheric processes. To assess the response of oyster-reef ( Crassostrea virginica ) growth to interannual variations in mean sea level (MSL) and improve long-term forecasts of reef response to rising seas, we monitored the morphology of constructed and natural intertidal reefs over 5 years using terrestrial lidar. Timing of reef scans created distinct periods of high and low relative water level for decade-old reefs ( n = 3) constructed in 1997 and 2000, young reefs ( n = 11) constructed in 2011 and one natural reef (approximately 100 years old). Changes in surface elevation were related to MSL trends. Decade-old reefs achieved 2 cm/year growth, which occurred along higher elevations when MSL increased. Young reefs experienced peak growth (6.7 cm/year) at a lower elevation that coincided with a drop in MSL. The natural reef exhibited considerable loss during the low MSL of the first time step but grew substantially during higher MSL through the second time step, with growth peaking (4.3 cm/year) at MSL, reoccupying the elevations previously lost. Oyster reefs appear to be in dynamic equilibrium with short-term (month-to-year) fluctuations in sea level, evidencing notable resilience to future changes to sea level that surpasses other coastal biogenic habitat types. These growth patterns support the presence of a previously defined optimal growth zone that shifts correspondingly with changes in MSL, which can help guide oyster-reef conservation and restoration.
Migration of northern yellowstone elk: Implications of spatial structuring
White, P.J.; Proffitt, K.M.; Mech, L.D.; Evans, S.B.; Cunningham, J.A.; Hamlin, K.L.
2010-01-01
Migration can enhance survival and recruitment of mammals by increasing access to higher-quality forage or reducing predation risk, or both. We used telemetry locations collected from 140 adult female elk during 20002003 and 20072008 to identify factors influencing the migration of northern Yellowstone elk. Elk wintered in 2 semidistinct herd segments and migrated 10140 km to at least 12 summer areas in Yellowstone National Park (YNP) and nearby areas of Montana. Spring migrations were delayed after winters with increased snow pack, with earlier migration in years with earlier vegetation green-up. Elk wintering at lower elevations outside YNP migrated an average of 13 days earlier than elk at higher elevations. The timing of autumn migrations varied annually, but elk left their summer ranges at about the same time regardless of elevation, wolf numbers, or distance to their wintering areas. Elk monitored for multiple years typically returned to the same summer (96 fidelity, n 52) and winter (61 fidelity, n 41) ranges. Elk that wintered at lower elevations in or near the northwestern portion of the park tended to summer in the western part of YNP (56), and elk that wintered at higher elevations spent summer primarily in the eastern and northern parts of the park (82). Elk did not grossly modify their migration timing, routes, or use areas after wolf restoration. Elk mortality was low during summer and migration (8 of 225 elk-summers). However, spatial segregation and differential mortality and recruitment between herd segments on the northern winter range apparently contributed to a higher proportion of the elk population wintering outside the northwestern portion of YNP and summering in the western portion of the park. This change could shift wolf spatial dynamics more outside YNP and increase the risk of transmission of brucellosis from elk to cattle north of the park. ?? 2010 American Society of Mammalogists.
Is UV-induced DNA damage greater at higher elevation?
Wang, Qing-Wei; Hidema, Jun; Hikosaka, Kouki
2014-05-01
• Although ultraviolet radiation (UV) is known to have negative effects on plant growth, there has been no direct evidence that plants growing at higher elevations are more severely affected by ultraviolet-B (UV-B) radiation, which is known to increase with elevation. We examined damage to DNA, a primary target of UV-B, in the widespread species Polygonum sachalinense (Fallopia sachalinensis) and Plantago asiatica at two elevations.• We sampled leaves of both species at 300 and 1700 m above sea level every 2 h for 11 d across the growing season and determined the level of cyclobutane pyrimidine dimer (CPD), a major product of UV damage to DNA.• The CPD level was significantly influenced by the time of day, date, elevation, and their interactions in both species. The CPD level tended to be higher at noon or on sunny days. DNA damage was more severe at 1700 m than at 300 m: on average, 8.7% greater at high elevation in P. asiatica and 7.8% greater in P. sachalinense Stepwise multiple regression analysis indicated that the CPD level was explained mainly by UV-B and had no significant relationship with other environmental factors such as temperature and photosynthetically active radiation.• UV-induced DNA damage in plants is greater at higher elevations. © 2014 Botanical Society of America, Inc.
NASA Astrophysics Data System (ADS)
Shi, Li-qun; Liu, Ying-zheng; Jin, Si-yu; Cao, Zhao-min
2007-12-01
A two-dimensional model of unsteady turbulent flow induced by high-speed elevator system was established in the present study. The research was focused on the instantaneous variation of the aerodynamic force on the car structure during traversing motion of the counter weight in the hoistway. A dynamic meshing method was employed to treat the multi-body motion system to avoid poor distortion of meshes. A comprehensive understanding of this significant aspect was obtained by varying the horizontal gap (Δ = 0.1m, 0.2m, and 0.3m) between the elevator car and the counter weight, and the moving speed ( U 0 = 2m/s, 6m/s, and 10m/s) of the elevator system. A pulsed intensification of the aerodynamic force on the elevator car and subsequent appearance of large valley with negative aerodynamic force were clearly observed in the numerical results. In parameters studied (Δ = 0.1m, U 0 = 2m/s, 6m/s, 10m/s), the peaked horizontal and vertical forces are respectively 7-11 and 4.3-5.65 times of that when the counter weight is far from the car. These results demonstrated the prominent influence of the traversing counter weight on aerodynamic force on the elevator car, which is of great significance to designers of high-speed elevator system.
Effect of innovative building design on physical activity.
Nicoll, Gayle; Zimring, Craig
2009-01-01
Stair climbing can be a low-cost and relatively accessible way to add everyday physical activity, but many building stairwells are inaccessible or unpleasant and elevators are far more convenient. This study explores the use of and attitude toward stairs in an innovative office building where the main elevators for able-bodied users stop only at every third floor ("skip-stop" elevators). These users are expected to walk up or down nearby stairs that have been made open and appealing ("skip-stop" stairs). The study takes advantage of a natural experiment. Some workers' offices were clustered around the skip-stop elevator and the stairs, whereas others had access to a traditional elevator core, that is, an elevator that stopped at each floor with nearby fire exit stairs. Stair use on the open skip-stop stairs and enclosed fire stairs was measured using infrared monitors and card-reader activity logs. An online survey of employees (N=299, a 17.4% response rate) gathered information on stair use and attitudes and behaviors toward physical activity; interviews with key personnel identified major implementation issues. The skip-stop stair was used 33 times more than the enclosed stair of the traditional elevator core, with 72% of survey participants reporting daily stair use. Although implementation issues related to organizational objectives, costs, security, barrier-free accessibility, and building codes exist, the skip-stop feature offers a successful strategy for increasing stair use in workplaces.
Czyz, Ewa K; Horwitz, Adam G; Eisenberg, Daniel; Kramer, Anne; King, Cheryl A
2013-01-01
This study sought to describe self-reported barriers to professional help seeking among college students who are at elevated suicide risk and determine if these barriers vary by demographic and clinical characteristics. Participants were 165 non-treatment seekers recruited as part of a Web-based treatment linkage intervention for college students at elevated suicide risk (from September 2010 through December 2011). Data were collected using Web-based questionnaires. Two coders coded students' responses to an open-ended question about reasons for not seeking professional help. The most commonly reported barriers included perception that treatment is not needed (66%), lack of time (26.8%), and preference for self-management (18%). Stigma was mentioned by only 12% of students. There were notable differences based on gender, race, and severity of depression and alcohol abuse. Efforts aimed at reaching students at elevated risk for suicidal behavior should be particularly sensitive to these commonly described barriers.
Light Levels, Refractive Development, and Myopia – a Speculative Review
Norton, Thomas T.; Siegwart, John T.
2013-01-01
Recent epidemiological evidence in children indicates that time spent outdoors is protective against myopia. Studies in animal models (chick, macaque, tree shrew) have found that light levels (similar to being in the shade outdoors) that are mildly elevated compared to indoor levels, slow form-deprivation myopia and (in chick and tree shrew) lens-induced myopia. Normal chicks raised in low light levels (50 lux) with a circadian light on/off cycle often develop spontaneous myopia. We propose a model in which the ambient illuminance levels produce a continuum of effects on normal refractive development and the response to myopiagenic stimuli such that low light levels favor myopia development and elevated levels are protective. Among possible mechanisms, elevation of retinal dopamine activity seems the most likely. Inputs from intrinsically-photosensitive retinal ganglion cells (ipRGCs) at elevated light levels may be involved, providing additional activation of retinal dopaminergic pathways. PMID:23680160
Leaf movement in Calathea lutea (Marantaceae).
Herbert, Thomas J; Larsen, Parry B
1985-09-01
Calathea lutea is a broad-leaved, secondary successional plant which shows complex leaf movements involving both elevation and folding of the leaf surface about the pulvinus. In the plants studied, mean leaf elevation increased from approximately 34 degrees in the early morning to 70 degrees at noon while the angle of leaf folding increased from 13 degrees to 50 degrees over the same time period. During the period from early morning to noon, these movements resulted in a significant decrease in the cosine of the angle of incidence, a measure of the direct solar radiation intercepted. The observed changes in elevational angle significantly reduce the cosine of angle of incidence while folding does not significantly reduce the fraction of direct solar radiation intercepted during the period of direct exposure of the leaf surface to the solar beam. Since elevational changes seem to account for the reduction in exposure to direct solar radiation, the role of folding remains unclear.
Determination of Sun Angles for Observations of Shock Waves on a Transport Aircraft
NASA Technical Reports Server (NTRS)
Fisher, David F.; Haering, Edward A., Jr.; Noffz, Gregory K.; Aguilar, Juan I.
1998-01-01
Wing compression shock shadowgraphs were observed on two flights during banked turns of an L-1011 aircraft at a Mach number of 0.85 and an altitude of 35,000 ft (10,700 m). Photos and video recording of the shadowgraphs were taken during the flights to document the shadowgraphs. Bright sunlight on the aircraft was required. The time of day, aircraft position, speed and attitudes were recorded to determine the sun azimuth and elevation relative to the wing quarter chord-line when the shadowgraphs were visible. Sun elevation and azimuth angles were documented for which the wing compression shock shadowgraphs were visible. The shadowgraph was observed for high to low elevation angles relative to the wing, but for best results high sun angles relative to the wing are desired. The procedures and equations to determine the sun azimuth and elevation angle with respect to the quarter chord-line is included in the Appendix.
Airborne observations reveal elevational gradient in tropical forest isoprene emissions.
Gu, Dasa; Guenther, Alex B; Shilling, John E; Yu, Haofei; Huang, Maoyi; Zhao, Chun; Yang, Qing; Martin, Scot T; Artaxo, Paulo; Kim, Saewung; Seco, Roger; Stavrakou, Trissevgeni; Longo, Karla M; Tóta, Julio; de Souza, Rodrigo Augusto Ferreira; Vega, Oscar; Liu, Ying; Shrivastava, Manish; Alves, Eliane G; Santos, Fernando C; Leng, Guoyong; Hu, Zhiyuan
2017-05-23
Isoprene dominates global non-methane volatile organic compound emissions, and impacts tropospheric chemistry by influencing oxidants and aerosols. Isoprene emission rates vary over several orders of magnitude for different plants, and characterizing this immense biological chemodiversity is a challenge for estimating isoprene emission from tropical forests. Here we present the isoprene emission estimates from aircraft eddy covariance measurements over the Amazonian forest. We report isoprene emission rates that are three times higher than satellite top-down estimates and 35% higher than model predictions. The results reveal strong correlations between observed isoprene emission rates and terrain elevations, which are confirmed by similar correlations between satellite-derived isoprene emissions and terrain elevations. We propose that the elevational gradient in the Amazonian forest isoprene emission capacity is determined by plant species distributions and can substantially explain isoprene emission variability in tropical forests, and use a model to demonstrate the resulting impacts on regional air quality.
Analytical investigation of the dynamics of tethered constellations in Earth orbit, phase 2
NASA Technical Reports Server (NTRS)
Lorenzini, Enrico C.
1987-01-01
A control law was developed to control the elevator during short-distance maneuvers along the tether of a 4-mass tethered system. This control law (called retarded exponential or RE) was analyzed parametrically in order to assess which control parameters provide a good dynamic response and a smooth time history of the acceleration on board the elevator. The short-distance maneuver under investigation consists of a slow crawling of the elevator over the distance of 10 m that represents a typical maneuver for fine tuning the acceleration level on board the elevator. The contribution of aerodynamic and thermal perturbations upon acceleration levels was also evaluated and acceleration levels obtained when such pertubations are taken into account were compared to those obtained by neglecting the thermal and aerodynamic forces. In addition, the preparation of a tether simulation questionnaire is illustrated. Analytic solutions to be compared to numerical cases and simulator test cases are also discussed.
Tracking formulas and strategies for a receiver oriented dual-axis tracking toroidal heliostat
DOE Office of Scientific and Technical Information (OSTI.GOV)
Guo, Minghuan; Wang, Zhifeng; Liang, Wenfeng
2010-06-15
A 4 m x 4 m toroidal heliostat with receiver oriented dual-axis tracking, also called spinning-elevation tracking, was developed as an auxiliary heat source for a hydrogen production system. A series of spinning-elevation tracking formulas have been derived for this heliostat. This included basic tracking formulas, a formula for the elevation angle for heliostat with a mirror-pivot offset, and a more general formula for the biased elevation angle. This paper presents the new tracking formulas in detail and analyzes the accuracy of applying a simplifying approximation. The numerical results show these receiver oriented dual-axis tracking formula approximations are accurate tomore » within 2.5 x 10{sup -6} m in image plane. Some practical tracking strategies are discussed briefly. Solar images from the toroidal heliostat at selected times are also presented. (author)« less
Acoustic testing of high temperature panels
NASA Technical Reports Server (NTRS)
Leatherwood, Jack D.; Clevenson, Sherman A.; Powell, Clemans A.; Daniels, Edward F.
1990-01-01
Results are presented of a series of thermal-acoustic tests conducted on the NASA Langley Research Center Thermal-Acoustic Test Apparatus to (1) investigate techniques for obtaining strain measurements on metallic and carbon-carbon materials at elevated temperature; (2) document the dynamic strain response characteristics of several superalloy honeycomb thermal protection system panels at elevated temperatures of up to 1200 F; and (3) determine the strain response and sonic fatigue behavior of four carbon-carbon panels at both ambient and elevated temperatures. A second study tested four carbon-carbon panels to document panel dynamic response characteristics at ambient and elevated temperature, determine time to failure and faliure modes, and collect continuous strain data up to panel failure. Strain data are presented from both types of panels, and problems encountered in obtaining reliable strain data on the carbon-carbon panels are described. The failure modes of the carbon-carbon panels are examined.
Breuckmann, F; Remberg, F; Böse, D; Lichtenberg, M; Kümpers, P; Pavenstädt, H; Waltenberger, J; Fischer, D
2016-03-01
This study aimed to analyze guideline adherence in the timing of invasive management for myocardial infarction without persistent ST-segment elevation (NSTEMI) in two exemplary German centers, comparing an urban university maximum care facility and a rural regional primary care facility. All patients diagnosed as having NSTEMI during 2013 were retrospectively enrolled in two centers: (1) site I, a maximum care center in an urban university setting, and (b) site II, a primary care center in a rural regional care setting. Data acquisition included time intervals from admission to invasive management, risk criteria, rate of intervention, and medical therapy. The median time from admission to coronary angiography was 12.0 h (site I) or 17.5 h (site II; p = 0.17). Guideline-adherent timing was achieved in 88.1 % (site I) or 82.9 % (site II; p = 0.18) of cases. Intervention rates were high in both sites (site I-75.5 % vs. site II-75.3 %; p = 0.85). Adherence to recommendations of medical therapy was high and comparable between the two sites. In NSTEMI or high-risk acute coronary syndromes without persistent ST-segment elevation, guideline-adherent timing of invasive management was achieved in about 85 % of cases, and was comparable between urban maximum and rural primary care settings. Validation by the German Chest Pain Unit Registry including outcome analysis is required.
Scholz, Karl Heinrich; Maier, Sebastian K G; Maier, Lars S; Lengenfelder, Björn; Jacobshagen, Claudius; Jung, Jens; Fleischmann, Claus; Werner, Gerald S; Olbrich, Hans G; Ott, Rainer; Mudra, Harald; Seidl, Karlheinz; Schulze, P Christian; Weiss, Christian; Haimerl, Josef; Friede, Tim; Meyer, Thomas
2018-04-01
The aim of this study was to investigate the effect of contact-to-balloon time on mortality in ST-segment elevation myocardial infarction (STEMI) patients with and without haemodynamic instability. Using data from the prospective, multicentre Feedback Intervention and Treatment Times in ST-Elevation Myocardial Infarction (FITT-STEMI) trial, we assessed the prognostic relevance of first medical contact-to-balloon time in n = 12 675 STEMI patients who used emergency medical service transportation and were treated with primary percutaneous coronary intervention (PCI). Patients were stratified by cardiogenic shock (CS) and out-of-hospital cardiac arrest (OHCA). For patients treated within 60 to 180 min from the first medical contact, we found a nearly linear relationship between contact-to-balloon times and mortality in all four STEMI groups. In CS patients with no OHCA, every 10-min treatment delay resulted in 3.31 additional deaths in 100 PCI-treated patients. This treatment delay-related increase in mortality was significantly higher as compared to the two groups of OHCA patients with shock (2.09) and without shock (1.34), as well as to haemodynamically stable patients (0.34, P < 0.0001). In patients with CS, the time elapsing from the first medical contact to primary PCI is a strong predictor of an adverse outcome. This patient group benefitted most from immediate PCI treatment, hence special efforts to shorten contact-to-balloon time should be applied in particular to these high-risk STEMI patients. NCT00794001.
Dantec, Cécile F; Vitasse, Yann; Bonhomme, Marc; Louvet, Jean-Marc; Kremer, Antoine; Delzon, Sylvain
2014-11-01
With global warming, an advance in spring leaf phenology has been reported worldwide. However, it is difficult to forecast phenology for a given species, due to a lack of knowledge about chilling requirements. We quantified chilling and heat requirements for leaf unfolding in two European tree species and investigated their relative contributions to phenological variations between and within populations. We used an extensive database containing information about the leaf phenology of 14 oak and 10 beech populations monitored over elevation gradients since 2005. In parallel, we studied the various bud dormancy phases, in controlled conditions, by regularly sampling low- and high-elevation populations during fall and winter. Oak was 2.3 times more sensitive to temperature for leaf unfolding over the elevation gradient and had a lower chilling requirement for dormancy release than beech. We found that chilling is currently insufficient for the full release of dormancy, for both species, at the lowest elevations in the area studied. Genetic variation in leaf unfolding timing between and within oak populations was probably due to differences in heat requirement rather than differences in chilling requirement. Our results demonstrate the importance of chilling for leaf unfolding in forest trees and indicate that the advance in leaf unfolding phenology with increasing temperature will probably be less pronounced than forecasted. This highlights the urgent need to determine experimentally the interactions between chilling and heat requirements in forest tree species, to improve our understanding and modeling of changes in phenological timing under global warming.
Cataldo, Maria Concetta; Calcara, Maria Luisa; Caputo, Giuseppe; Mammina, Caterina
2012-04-01
Stroke is a disabling disease. In elderly populations, stroke is the third leading cause of death and the primary cause of reduction in or loss of functional ability and personal autonomy. Possible associations between levels of total serum cholesterol (TC) and both incidence of stroke and functional outcomes after rehabilitation are still under study. To detect positive and negative prognostic factors associated with functional outcomes in first-time stroke patients admitted to an integrated home care rehabilitative program. This study enrolled 141 patients with a first-time stroke who were admitted to a home care rehabilitation program. Primary outcome measures were the Barthel activities of daily living (ADL) and mobility indices at the beginning and end of the rehabilitative treatment. The impact of TC and other demographic and clinical variables was analyzed using bivariate and multivariate logistic regression analyses. Age and Short Portable Mental Status Questionnaire (SPMSQ) score were negatively associated with functional outcome. In contrast, elevated TC was positively associated with a better home rehabilitative treatment outcome. Barthel index score at admission was negatively associated with outcomes assessed by the Barthel ADL index and age with outcomes assessed by the Barthel mobility index. In a multivariate logistic regression analysis, SPMSQ score and elevated TC were significantly associated with outcome. Specifically, higher SPMSQ scores were negatively associated with better rehabilitative treatment outcomes, whereas elevated TC was positively associated. Elevated TC seems to be associated with better functional outcomes in patients with first-time stroke. Copyright © 2012 Elsevier Inc. All rights reserved.
Peterson, Gunnel; Dedering, Åsa; Andersson, Erika; Nilsson, David; Trygg, Johan; Peolsson, Michael; Wallman, Thorne; Peolsson, Anneli
2015-04-01
Previous studies have shown altered neck muscle function in individuals with chronic whiplash associated disorder (WAD). However, we lack real-time investigations with non-invasive methods that can distinguish between the different ventral neck muscle layers. This study investigated deformations and deformation rates in the sternocleidomastoid (SCM), longus capitis (Lcap), and longus colli (Lco) muscles with real-time ultrasonography. Twenty-six individuals with WAD were compared with 26 controls, matched for age and sex. Ultrasound imaging of the SCM, Lcap, and Lco were recorded during 10 repetitive arm elevations. The first and tenth arm elevations were post-process analyzed with speckle tracking. There were few significant differences in the deformations or deformation rates in the SCM, Lcap, and Lco between the WAD and control group. In controls, deformations and deformation rates showed linear positive relationships between SCM/Lcap, SCM/Lco, and Lcap/Lco which increased from the first arm elevation (R(2) = 0.14-0.70); to the tenth arm elevation (R(2) = 0.51-0.71). The WAD group showed similar or weaker linear relationship (R(2) < 0.19) during the tenth compared to the first (R(2) < 0.44) arm elevation except for deformations in Lcap/Lco (R(2) = 0.13-0.57). This result indicated that deformations and deformation rates in one muscle were correlated by similar deformations and deformation rates in other neck muscles in the control group, but this interplay between muscles was not found in the WAD group. Copyright © 2014 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Ismail, M. A. M.; Kumar, N. S.; Abidin, M. H. Z.; Madun, A.
2018-04-01
This study is about systematic approach to photogrammetric survey that is applicable in the extraction of elevation data for geophysical surveys in hilly terrains using Unmanned Aerial Vehicles (UAVs). The outcome will be to acquire high-quality geophysical data from areas where elevations vary by locating the best survey lines. The study area is located at the proposed construction site for the development of a water reservoir and related infrastructure in Kampus Pauh Putra, Universiti Malaysia Perlis. Seismic refraction surveys were carried out for the modelling of the subsurface for detailed site investigations. Study were carried out to identify the accuracy of the digital elevation model (DEM) produced from an UAV. At 100 m altitude (flying height), over 135 overlapping images were acquired using a DJI Phantom 3 quadcopter. All acquired images were processed for automatic 3D photo-reconstruction using Agisoft PhotoScan digital photogrammetric software, which was applied to all photogrammetric stages. The products generated included a 3D model, dense point cloud, mesh surface, digital orthophoto, and DEM. In validating the accuracy of the produced DEM, the coordinates of the selected ground control point (GCP) of the survey line in the imaging area were extracted from the generated DEM with the aid of Global Mapper software. These coordinates were compared with the GCPs obtained using a real-time kinematic global positioning system. The maximum percentage of difference between GCP’s and photogrammetry survey is 13.3 %. UAVs are suitable for acquiring elevation data for geophysical surveys which can save time and cost.
Karuri, A R; Agarwal, R K; Engelking, L R; Kumar, M S
1998-03-15
Effects of acute exposure (2 hr) to either 1.5% halothane or 0.5% methoxyflurane were investigated in the Sprague Dawley rat. Pituitary (PIT) and central nervous system (CNS) substance P (SP)-like and beta-endorphin (beta-end)-like immunoreactivities were evaluated immediately after anesthetic exposure (2 h), after righting reflex (4 h) or 24 hr postexposure (24 h). Only halothane significantly reduced SP-like immunoreactivity in olfactory bulbs in both the 2-h and 4-h groups. Halothane elevated SP-like immunoreactivity of hippocampus at all three time periods, and in the hypothalamus at 2 h. Both anesthetics significantly depleted thalamic concentrations of SP-like immunoreactivity. Methoxyflurane anesthesia resulted in a drastic decrease in SP-like immunoreactivity in PIT at all three time periods periods, while halothane elevated PIT concentrations of this peptide at 4 h. Both anesthetics significantly decreased beta-end-like immunoreactivity in the olfactory bulbs and thalami at 2, 4, and 24 h. However, halothane alone significantly elevated beta-end-like immunoreactivity in the spinal cord at 24 h. Halothane significantly elevated PIT beta-end-like immunoreactivity at 2 and 24 h, while methoxyflurane significantly lowered it in the 4-h group, but elevated the levels of the same in the 24-h group. Brain stem beta-end immunoreactivity were significantly reduced at 2 h by both anesthetics, and at 4 h by methoxyflurane. Results indicate that halothane and methoxyflurane may differ significantly in their actions on SP and beta-end secreting neurons in the CNS.
Ocean Acidification Affects the Phyto-Zoo Plankton Trophic Transfer Efficiency
Cripps, Gemma; Flynn, Kevin J.; Lindeque, Penelope K.
2016-01-01
The critical role played by copepods in ocean ecology and biogeochemistry warrants an understanding of how these animals may respond to ocean acidification (OA). Whilst an appreciation of the potential direct effects of OA, due to elevated pCO2, on copepods is improving, little is known about the indirect impacts acting via bottom-up (food quality) effects. We assessed, for the first time, the chronic effects of direct and/or indirect exposures to elevated pCO2 on the behaviour, vital rates, chemical and biochemical stoichiometry of the calanoid copepod Acartia tonsa. Bottom-up effects of elevated pCO2 caused species-specific biochemical changes to the phytoplanktonic feed, which adversely affected copepod population structure and decreased recruitment by 30%. The direct impact of elevated pCO2 caused gender-specific respiratory responses in A.tonsa adults, stimulating an enhanced respiration rate in males (> 2-fold), and a suppressed respiratory response in females when coupled with indirect elevated pCO2 exposures. Under the combined indirect+direct exposure, carbon trophic transfer efficiency from phytoplankton-to-zooplankton declined to < 50% of control populations, with a commensurate decrease in recruitment. For the first time an explicit role was demonstrated for biochemical stoichiometry in shaping copepod trophic dynamics. The altered biochemical composition of the CO2-exposed prey affected the biochemical stoichiometry of the copepods, which could have ramifications for production of higher tropic levels, notably fisheries. Our work indicates that the control of phytoplankton and the support of higher trophic levels involving copepods have clear potential to be adversely affected under future OA scenarios. PMID:27082737
NASA Astrophysics Data System (ADS)
Pérez Quezadas, Juan; Heilweil, Victor M.; Cortés Silva, Alejandra; Araguas, Luis; Salas Ortega, María del Rocío
2016-12-01
Geochemistry and environmental tracers were used to understand groundwater resources, recharge processes, and potential sources of contamination in the Rio Actopan Basin, Veracruz State, Mexico. Total dissolved solids are lower in wells and springs located in the basin uplands compared with those closer to the coast, likely associated with rock/water interaction. Geochemical results also indicate some saltwater intrusion near the coast and increased nitrate near urban centers. Stable isotopes show that precipitation is the source of recharge to the groundwater system. Interestingly, some high-elevation springs are more isotopically enriched than average annual precipitation at higher elevations, indicating preferential recharge during the drier but cooler winter months when evapotranspiration is reduced. In contrast, groundwater below 1,200 m elevation is more isotopically depleted than average precipitation, indicating recharge occurring at much higher elevation than the sampling site. Relatively cool recharge temperatures, derived from noble gas measurements at four sites (11-20 °C), also suggest higher elevation recharge. Environmental tracers indicate that groundwater residence time in the basin ranges from 12,000 years to modern. While this large range shows varying groundwater flowpaths and travel times, ages using different tracer methods (14C, 3H/3He, CFCs) were generally consistent. Comparing multiple tracers such as CFC-12 with CFC-113 indicates piston-flow to some discharge points, yet binary mixing of young and older groundwater at other points. In summary, groundwater within the Rio Actopan Basin watershed is relatively young (Holocene) and the majority of recharge occurs in the basin uplands and moves towards the coast.
Shen, Jie; Burgess, Diane J
2012-01-17
Dexamethasone loaded poly(lactic-co-glycolic acid) (PLGA) microsphere/PVA hydrogel composites have been investigated as an outer drug-eluting coating for implantable devices such as glucose sensors to counter negative tissue responses to implants. The objective of this study was to develop a discriminatory, accelerated in vitro release testing method for this drug-eluting coating using United States Pharmacopeia (USP) apparatus 4. Polymer degradation and drug release kinetics were investigated under "real-time" and accelerated conditions (i.e. extreme pH, hydro-alcoholic solutions and elevated temperatures). Compared to "real-time" conditions, the initial burst and lag phases were similar using hydro-alcoholic solutions and extreme pH conditions, while the secondary apparent zero-order release phase was slightly accelerated. Elevated temperatures resulted in a significant acceleration of dexamethasone release. The accelerated release data were able to predict "real-time" release when applying the Arrhenius equation. Microsphere batches with faster and slower release profiles were investigated under "real-time" and elevated temperature (60°C) conditions to determine the discriminatory ability of the method. The results demonstrated both the feasibility and the discriminatory ability of this USP apparatus 4 method for in vitro release testing of drug loaded PLGA microsphere/PVA hydrogel composites. This method may be appropriate for similar drug/device combination products and drug delivery systems. Copyright © 2011 Elsevier B.V. All rights reserved.
Poland, Michael P.
2014-01-01
Differencing digital elevation models (DEMs) derived from TerraSAR add-on for Digital Elevation Measurements (TanDEM-X) synthetic aperture radar imagery provides a measurement of elevation change over time. On the East Rift Zone (EZR) of Kīlauea Volcano, Hawai‘i, the effusion of lava causes changes in topography. When these elevation changes are summed over the area of an active lava flow, it is possible to quantify the volume of lava emplaced at the surface during the time spanned by the TanDEM-X data—a parameter that can be difficult to measure across the entirety of an ~100 km2 lava flow field using ground-based techniques or optical remote sensing data. Based on the differences between multiple TanDEM-X-derived DEMs collected days to weeks apart, the mean dense-rock equivalent time-averaged discharge rate of lava at Kīlauea between mid-2011 and mid-2013 was approximately 2 m3/s, which is about half the long-term average rate over the course of Kīlauea's 1983–present ERZ eruption. This result implies that there was an increase in the proportion of lava stored versus erupted, a decrease in the rate of magma supply to the volcano, or some combination of both during this time period. In addition to constraining the time-averaged discharge rate of lava and the rates of magma supply and storage, topographic change maps derived from space-based TanDEM-X data provide insights into the four-dimensional evolution of Kīlauea's ERZ lava flow field. TanDEM-X data are a valuable complement to other space-, air-, and ground-based observations of eruptive activity at Kīlauea and offer great promise at locations around the world for aiding with monitoring not just volcanic eruptions but any hazardous activity that results in surface change, including landslides, floods, earthquakes, and other natural and anthropogenic processes.
Liu, Dongyan; Tago, Kanako; Hayatsu, Masahito; Tokida, Takeshi; Sakai, Hidemitsu; Nakamura, Hirofumi; Usui, Yasuhiro; Hasegawa, Toshihiro; Asakawa, Susumu
2016-01-01
Elevated concentrations of atmospheric CO2 ([CO2]) enhance the production and emission of methane in paddy fields. In the present study, the effects of elevated [CO2], elevated temperature (ET), and no nitrogen fertilization (LN) on methanogenic archaeal and methane-oxidizing bacterial community structures in a free-air CO2 enrichment (FACE) experimental paddy field were investigated by PCR-DGGE and real-time quantitative PCR. Soil samples were collected from the upper and lower soil layers at the rice panicle initiation (PI) and mid-ripening (MR) stages. The composition of the methanogenic archaeal community in the upper and lower soil layers was not markedly affected by the elevated [CO2], ET, or LN condition. The abundance of the methanogenic archaeal community in the upper and lower soil layers was also not affected by elevated [CO2] or ET, but was significantly increased at the rice PI stage and significantly decreased by LN in the lower soil layer. In contrast, the composition of the methane-oxidizing bacterial community was affected by rice-growing stages in the upper soil layer. The abundance of methane-oxidizing bacteria was significantly decreased by elevated [CO2] and LN in both soil layers at the rice MR stage and by ET in the upper soil layer. The ratio of mcrA/pmoA genes correlated with methane emission from ambient and FACE paddy plots at the PI stage. These results indicate that the decrease observed in the abundance of methane-oxidizing bacteria was related to increased methane emission from the paddy field under the elevated [CO2], ET, and LN conditions. PMID:27600710
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gillespie, K.M.; Rogers, A.; Ainsworth, E. A.
2011-01-31
Soybeans (Glycine max Merr.) were grown at elevated carbon dioxide concentration ([CO{sub 2}]) or chronic elevated ozone concentration ([O{sub 3}]; 90 ppb), and then exposed to an acute O{sub 3} stress (200 ppb for 4 h) in order to test the hypothesis that the atmospheric environment alters the total antioxidant capacity of plants, and their capacity to respond to an acute oxidative stress. Total antioxidant metabolism, antioxidant enzyme activity, and antioxidant transcript abundance were characterized before, immediately after, and during recovery from the acute O{sub 3} treatment. Growth at chronic elevated [O{sub 3}] increased the total antioxidant capacity of plants,more » while growth at elevated [CO{sub 2}] decreased the total antioxidant capacity. Changes in total antioxidant capacity were matched by changes in ascorbate content, but not phenolic content. The growth environment significantly altered the pattern of antioxidant transcript and enzyme response to the acute O{sub 3} stress. Following the acute oxidative stress, there was an immediate transcriptional reprogramming that allowed for maintained or increased antioxidant enzyme activities in plants grown at elevated [O{sub 3}]. Growth at elevated [CO{sub 2}] appeared to increase the response of antioxidant enzymes to acute oxidative stress, but dampened and delayed the transcriptional response. These results provide evidence that the growth environment alters the antioxidant system, the immediate response to an acute oxidative stress, and the timing over which plants return to initial antioxidant levels. The results also indicate that future elevated [CO{sub 2}] and [O{sub 3}] will differentially affect the antioxidant system.« less
Elfil, H; Crowley, L; Segurado, R; Spring, A
2015-11-01
A head-elevation pillow places a patient in a ramped posture, which maximises the view of the larynx during laryngoscopy, particularly in obese parturients. In our institution an elevation pillow is used pre-emptively for neuraxial anaesthesia. We hypothesised that head-elevation may impair cephalad spread of local anaesthetic before caesarean section resulting in a lower block or longer time to achieve a T6 level. We aimed to investigate the effect of head-elevation on spread of intrathecal local anaesthetics during anaesthesia for caesarean section. One-hundred parturients presenting for caesarean section under combined spinal-epidural anaesthesia were randomised to either the standard supine position with lateral displacement or in the supine position with lateral displacement on an head-elevation pillow. Each patient received intrathecal hyperbaric bupivacaine 11 mg, morphine 100 μg and fentanyl 15 μg. Patients were assessed for adequacy of sensory block (T6 or higher) at 10 min. Sensory block to T6 was achieved within 10 min in 65.9% of parturients in the Elevation Pillow Group compared to 95.7% in the Control Group (P<0.05). Compared to the Control Group, patients in the Elevation Pillow Group had greater requirements for epidural supplementation (43.5% vs 2.1%, P<0.001) or conversion to general anaesthesia (9.3% vs 0%, P<0.04). Use of a ramped position with an head-elevation pillow following injection of the intrathecal component of a combined spinal-epidural anaesthetic for scheduled caesarean section was associated with a significantly lower block height at 10min. Copyright © 2015 Elsevier Ltd. All rights reserved.
Enhanced Climatic Warming in the Tibetan Plateau Due to Double CO2: A Model Study
NASA Technical Reports Server (NTRS)
Chen, Baode; Chao, Winston C.; Liu, Xiao-Dong; Lau, William K. M. (Technical Monitor)
2001-01-01
The NCAR (National Center for Atmospheric Research) regional climate model (RegCM2) with time-dependent lateral meteorological fields provided by a 130-year transient increasing CO2 simulation of the NCAR Climate System Model (CSM) has been used to investigate the mechanism of enhanced ground temperature warming over the TP (Tibetan Plateau). From our model results, a remarkable tendency of warming increasing with elevation is found for the winter season, and elevation dependency of warming is not clearly recognized in the summer season. This simulated feature of elevation dependency of ground temperature is consistent with observations. Based on an analysis of surface energy budget, the short wave solar radiation absorbed at the surface plus downward long wave flux reaching the surface shows a strong elevation dependency, and is mostly responsible for enhanced surface warming over the TP. At lower elevations, the precipitation forced by topography is enhanced due to an increase in water vapor supply resulted from a warming in the atmosphere induced by doubling CO2. This precipitation enhancement must be associated with an increase in clouds, which results in a decline in solar flux reaching surface. At higher elevations, large snow depletion is detected in the 2xCO2run. It leads to a decrease in albedo, therefore more solar flux is absorbed at the surface. On the other hand, much more uniform increase in downward long wave flux reaching the surface is found. The combination of these effects (i.e. decrease in solar flux at lower elevations, increase in solar flux at higher elevation and more uniform increase in downward long wave flux) results in elevation dependency of enhanced ground temperature warming over the TP.
Liu, Dongyan; Tago, Kanako; Hayatsu, Masahito; Tokida, Takeshi; Sakai, Hidemitsu; Nakamura, Hirofumi; Usui, Yasuhiro; Hasegawa, Toshihiro; Asakawa, Susumu
2016-09-29
Elevated concentrations of atmospheric CO2 ([CO2]) enhance the production and emission of methane in paddy fields. In the present study, the effects of elevated [CO2], elevated temperature (ET), and no nitrogen fertilization (LN) on methanogenic archaeal and methane-oxidizing bacterial community structures in a free-air CO2 enrichment (FACE) experimental paddy field were investigated by PCR-DGGE and real-time quantitative PCR. Soil samples were collected from the upper and lower soil layers at the rice panicle initiation (PI) and mid-ripening (MR) stages. The composition of the methanogenic archaeal community in the upper and lower soil layers was not markedly affected by the elevated [CO2], ET, or LN condition. The abundance of the methanogenic archaeal community in the upper and lower soil layers was also not affected by elevated [CO2] or ET, but was significantly increased at the rice PI stage and significantly decreased by LN in the lower soil layer. In contrast, the composition of the methane-oxidizing bacterial community was affected by rice-growing stages in the upper soil layer. The abundance of methane-oxidizing bacteria was significantly decreased by elevated [CO2] and LN in both soil layers at the rice MR stage and by ET in the upper soil layer. The ratio of mcrA/pmoA genes correlated with methane emission from ambient and FACE paddy plots at the PI stage. These results indicate that the decrease observed in the abundance of methane-oxidizing bacteria was related to increased methane emission from the paddy field under the elevated [CO2], ET, and LN conditions.
NASA Astrophysics Data System (ADS)
Nagai, S.; Suzuki, R.
2015-12-01
The biomass of tropical forests sequestrates tons of carbon and plays an important role in the global carbon cycle regulating the climate. Also its high biodiversity ecosystems bring us many valuable resources and cultural and educational ecosystem services. However, large areas of the tropical forest are deforested and converted to oil palm or acacia plantation for the economic benefit of the local society mainly in Southeast Asia. Monitoring of the tropical forest from satellites provides us the information about the deforestation for decadal time period over extensive areas and enables us to discuss it from a scientific point of view. The purpose of this study is to reveal the interannual change and recent trend of deforestation in relation to the land elevation for decadal time period over Borneo by using data from Moderate Resolution Imaging Spectroradiometer (MODIS). We acquired the atmospherically corrected and cloud free Terra-MODIS and Aqua-MODIS daily data products (MOD09GA and MYD09GA; collection 5) from 2001 to 2013 for Borneo. We extracted the pixel values in the 500m surface reflectance bands 1 (red) and 4 (green) products and calculated the green-red vegetation index (GRVI), (band 4 - band 1) / (band 4 + band 1), at a daily time step. GRVI shows a positive value for the land prevailed by green vegetation, while it shows a negative value for the land prevailed by no-green components such as bare land. As for the elevation data, ASTER Global Digital Elevation Model (GDEM) which has 33.3m spatial resolution was employed. The original resolution was resampled to the grid system of MODIS data (i.e. 500m resolution). Pixels which had a negative GRVI ratio more than 80 % (termed as "no green pixel") in each year were regarded as the land characterized by no vegetation, and mapped the distribution for each year. Throughout the 13 years, no green pixels mainly found over the coastal low land below 20m of the elevation and the area was almost constant (around 3000km2). It is considered the deforestation for the plantations generally occurred over the easy access low lands. By contrast, it was obvious that no green pixels extended their distribution up to high elevation (20 to 120m) areas mainly after 2006. This trend suggests recent development of the plantation has been extended to relatively inland and high elevation areas.
Zhang, Lisheng; Zhang, Lingling; Shi, Dongtao; Wei, Jing; Chang, Yaqing
2017-01-01
Increases in ocean temperature due to climate change are predicted to change the behaviors of marine invertebrates. Altered behaviors of keystone ecosystem engineers such as echinoderms will have consequences for the fitness of individuals, which are expected to flow on to the local ecosystem. Relatively few studies have investigated the behavioral responses of echinoderms to long-term elevated temperature. We investigated the effects of exposure to long-term (∼31 weeks) elevated temperature (∼3 °C above the ambient water temperature) on covering, sheltering and righting behaviors of the sea urchin Strongylocentrotus intermedius. Long-term elevated temperature showed different effects on the three behaviors. It significantly decreased covering behavior, including both covering behavior reaction (time to first covering) and ability (number of covered sea urchins and number of shells used for covering). Conversely, exposure to long-term elevated temperature significantly increased sheltering behavior. Righting response in S. intermedius was not significantly different between temperature treatments. The results provide new information into behavioral responses of echinoderms to ocean warming. PMID:28348933
Lehmer, E.M.; Biggins, D.E.
2005-01-01
We compared over-winter body temperature (Tb) patterns for more than 6 months in adult (> 1 year) black-tailed (Cynomys ludovicianus) and Utah (C. parvidens) prairie dogs from colonies located along gradients of elevation in northern Colorado and southern Utah. In general, black-tailed prairie dogs entered torpor facultatively during winter, whereas Utah prairie dogs hibernated continuously for extended periods. Both black-tailed and Utah prairie dogs displayed significant differences in Tb patterns across elevations, with lower elevation populations entering more shallow and infrequent torpor than prairie dogs at higher elevations. Tb patterns of black-tailed prairie dogs followed 24-h cycles, as most prairie dogs entered into and aroused from torpor between 1100 and 1700 h and bout lengths were clustered around 24-h intervals and multiples thereof. Torpor in Utah prairie dogs did not display the same daily patterns; they entered into and aroused from torpor at all times of the day, and bout lengths were variable. Although black-tailed and Utah prairie dogs are closely related, mechanisms that stimulate and control torpor might differ between them.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Denoyelles, F.; Dewey, S.L.; Bergin, S.
Below the epilimnion in some lakes dense bands of phytolankton biomass of species rare or absent in the epilimnion can develop. With adequate light for photosynthesis reaching these often nutrient-rich depths and with at least a few weeks of stratification to allow time for their development, certain species become abundant from growth in place. The quantity of light and duration of stratification greatly influence these very sensitive phytoplankton conditions. Because these important environmental conditions are controlled-greatly by climate, deep-dwelling algal communities were affected by climate differences associated with elevation, in a 5-year study of 10 lakes ranging in elevation betweenmore » 2938 and 3353 m in the Medicine Bow Mountains of SE Wyoming. These results suggest that with even a slight change in climatic conditions at a given latitude and elevation, subepilimnetic phytoplankton communities in higher elevation lakes will rapidly become more like those in lower elevation lakes (warming trend), and vice versa (cooling trend).« less
Finsterer, Josef; Aliyev, Rahim
2017-07-27
BACKGROUND Whether creatine-kinase (CK) is elevated or not in chronic inflammatory demyelinating polyneuropathy (CIDP) and its variants is not comprehensively investigated. CASE REPORT We report the case of a 47-year-old male who developed weakness of the left lower leg and the right index finger at age 42 years. At age 44 years, paresthesias and dysesthesias of both lower legs and mild right lower leg weakness additionally developed. CK was recurrently elevated since age 42 years but paraprotein and anti-myelin-associated glycoprotein (MAG)-antibodies were negative. Nerve conduction studies at age 43 years showed an axonal and demyelinating lesion with conduction blocks. Cerebrospinal fluid (CSF) investigations revealed mild pleocytosis and elevated protein, which is why CIDP variant was diagnosed. Immunoglobulins were administered with success. Because of recurrent relapses, immunoglobulins were increased at age 45 years, resulting in stabilization. Currently, the patient is infusing immunoglobulins subcutaneously himself. CONCLUSIONS CIDP variants may go along with CK elevation, an axonal lesion, pleocytosis, and asymmetry of the lesion. A vanishing effect of immunoglobulins over time may be characteristic of CIDP variants.
Poganiatz, I; Wagner, H
2001-04-01
Interaural level differences play an important role for elevational sound localization in barn owls. The changes of this cue with sound location are complex and frequency dependent. We exploited the opportunities offered by the virtual space technique to investigate the behavioral relevance of the overall interaural level difference by fixing this parameter in virtual stimuli to a constant value or introducing additional broadband level differences to normal virtual stimuli. Frequency-specific monaural cues in the stimuli were not manipulated. We observed an influence of the broadband interaural level differences on elevational, but not on azimuthal sound localization. Since results obtained with our manipulations explained only part of the variance in elevational turning angle, we conclude that frequency-specific cues are also important. The behavioral consequences of changes of the overall interaural level difference in a virtual sound depended on the combined interaural time difference contained in the stimulus, indicating an indirect influence of temporal cues on elevational sound localization as well. Thus, elevational sound localization is influenced by a combination of many spatial cues including frequency-dependent and temporal features.
High frequency and large deposition of acid fog on high elevation forest.
Igawa, Manabu; Matsumura, Ko; Okochi, Hiroshi
2002-01-01
We have collected and analyzed fogwater on the mountainside of Mt. Oyama (1252 m) in the Tanzawa Mountains of Japan and observed the fog event frequency from the base of the mountain with a video camera. The fog event frequency increased with elevation and was observed to be present 46% of the year at the summit. The water deposition via throughfall increased with elevation because of the increase in fogwater interception and was about twice that via rain at the summit, where the air pollutant deposition via throughfall was several times that via rainwater. The dry deposition and the deposition via fogwater were dominant factors in the total ion deposition at high elevation sites. In a fog event, nitric acid, the major acid component on the mountain, is formed during the transport of the air mass from the base of the mountain along the mountainside, where gases including nitric acid deposit and are scavenged by fogwater. Therefore, high acidity caused by nitric acid and relatively low ion strength are observed in the fogwater at high elevation sites.
Reliability and life prediction of ceramic composite structures at elevated temperatures
NASA Technical Reports Server (NTRS)
Duffy, Stephen F.; Gyekenyesi, John P.
1994-01-01
Methods are highlighted that ascertain the structural reliability of components fabricated of composites with ceramic matrices reinforced with ceramic fibers or whiskers and subject to quasi-static load conditions at elevated temperatures. Each method focuses on a particular composite microstructure: whisker-toughened ceramics, laminated ceramic matrix composites, and fabric reinforced ceramic matrix composites. In addition, since elevated service temperatures usually involve time-dependent effects, a section dealing with reliability degradation as a function of load history has been included. A recurring theme throughout this chapter is that even though component failure is controlled by a sequence of many microfailure events, failure of ceramic composites will be modeled using macrovariables.
Vegetation Greenness and Its Drivers across Ice-free Greenland
NASA Astrophysics Data System (ADS)
Pedersen, S. H.; Liston, G. E.; Tamstorf, M. P.; Schmidt, N. M.
2017-12-01
The coastal and mountain areas surrounding the Greenland Ice Sheet cover one-fifth of Greenland. This ice-free area spans more than 20 degrees latitude and includes high-, low-, and sub-Arctic climate zones and the terrain varies from sea level to 3700 m elevation. Hence, this area contains a wide range of vegetation growing conditions associated with precipitation, temperature, and incoming solar radiation found across these latitudinal, elevational, and coast-inland gradients. In this study, we mapped the spatial distribution of vegetation at 300-m spatial resolution across ice-free Greenland using the annual maximum vegetation greenness (MaxNDVI) and the timing of MaxNDVI derived from daily Moderate Resolution Imaging Spectroradiometer (MODIS) reflectance data from 2000-2015. Further, we investigated the drivers of the annual MaxNDVI and its timing across the diverse vegetation growing conditions in Greenland using modeled climatic variables, including snow quantity and timing, at the same temporal and spatial resolutions. The annual average MaxNDVI varied between 0.3 and 0.5 in North Greenland, and 0.6 and 0.9 in South Greenland. The timing of MaxNDVI differed more than two weeks between North and South Greenland. The potential growing season, e.g., the period with no snow on the ground, was as short as one month in North Greenland (mainly August), and four to five times longer in South Greenland (typically starting in mid-May). The snow-free date varied with elevation, from valley bottoms to the mountain tops, having the same range that existed from South to North Greenland. Our results show that MaxNDVI and its timing are significantly driven by the timing of snow-free ground and the amount of meltwater available from the snowpack during spring snowmelt.
Elmore, A.J.; Guinn, S.M.; Minsley, B.J.; Richardson, A.D.
2012-01-01
The timing of spring leaf development, trajectories of summer leaf area, and the timing of autumn senescence have profound impacts to the water, carbon, and energy balance of ecosystems, and are likely influenced by global climate change. Limited field-based and remote-sensing observations have suggested complex spatial patterns related to geographic features that influence climate. However, much of this variability occurs at spatial scales that inhibit a detailed understanding of even the dominant drivers. Recognizing these limitations, we used nonlinear inverse modeling of medium-resolution remote sensing data, organized by day of year, to explore the influence of climate-related landscape factors on the timing of spring and autumn leaf-area trajectories in mid-Atlantic, USA forests. We also examined the extent to which declining summer greenness (greendown) degrades the precision and accuracy of observations of autumn offset of greenness. Of the dominant drivers of landscape phenology, elevation was the strongest, explaining up to 70% of the spatial variation in the onset of greenness. Urban land cover was second in importance, influencing spring onset and autumn offset to a distance of 32 km from large cities. Distance to tidal water also influenced phenological timing, but only within ~5 km of shorelines. Additionally, we observed that (i) growing season length unexpectedly increases with increasing elevation at elevations below 275 m; (ii) along gradients in urban land cover, timing of autumn offset has a stronger effect on growing season length than does timing of spring onset; and (iii) summer greendown introduces bias and uncertainty into observations of the autumn offset of greenness. These results demonstrate the power of medium grain analyses of landscape-scale phenology for understanding environmental controls on growing season length, and predicting how these might be affected by climate change.
Feng, Qun; Li, Xiao-yu; Luan, Yong-fu; Sun, Sai-nan; Sun, Rong
2015-03-01
To study the effect of single administration of aqueous extracts from aconite on "dose-toxicity" relationship and "time-toxicity" relationship of mice hearts, through changes in electrocardiogram (ECG) and serum biochemical indexes. Mice were grouped according to different drug doses and time points, and orally administered with water extracts from aconite for once to observe the changes of mice ECG before and after the administration, calculate visceral indexes heart, liver and kidney, and detect levels of CK, LDH, BNP and CTn-I in serum. According to the "time-toxicity" relationship study, at 5 min after oral administration with aqueous extracts from aconite in mice, the heart rate of mice began rising, reached peak at 60 min and then slowly reduced; QRS, R amplitude, T duration and amplitude and QT interval declined at 5 min, reduced to the bottom at 60 min and then gradually elevated. The levels of CK, LDH, BNP and CTn-I in serum elevated at 5 min and reached the peak at 60 min, with no significant change in ratios of organs to body at different time points. On the basis of the "dose-toxicity" relationship, with the increase in single dose of aqueous extracts from aconite, the heart rate of mice. QRS, T duration and amplitude and QT interval declined gradually, and levels of CK, LDH, BNP and CTn-I in serum slowly elevated, with a certain dose dependence and no significant change in ratios of organs to body in mice. Single oral administration of different doses of aqueous extracts from aconite could cause different degrees of heart injury at different time points, with a certain dose dependence. Its peak time of toxicity is at 60 min after the administration of aqueous extracts from aconite.
Stress and Traumatic Brain Injury: A Behavioral, Proteomics, and Histological Study
2011-03-07
time point. They had elevated levels of serum corticosterone (CORT) and hippocampal IL-6 but no other cellular or protein changes. Stressed injured...rats had an increased number of TUNEL-positive cells in the HC and elevated GFAP and Iba1 immunoreactivity in the HC and the PFC. Our findings suggest...neuronal and glial cell loss, inflammation, and gliosis. These findings may have implications in the development of diagnostic and therapeutic measures
103. Photographic copy of drawing (1905, original drawing in Archives, ...
103. Photographic copy of drawing (1905, original drawing in Archives, Office of the Building, Administration Building, Sears, Roebuck and Company Mail Order Plant, Chicago, Illinois). Nimmons and Fellows. 1/8 inch to one foot. South elevation adjacent to the railroad tracks; only the first three floors were built at that time. SOUTH ELEVATION - ANNEX A - Sears Roebuck & Company Mail Order Plant, Merchandise Building, 924 South Homan Avenue, Chicago, Cook County, IL
104. Photographic copy of drawing (1905, original drawing in Archives, ...
104. Photographic copy of drawing (1905, original drawing in Archives, Office of the Building, Administration Building, Sears, Roebuck and Company Mail Order Plant, Chicago, Illinois). Nimmons and Fellows. 1/8 inch to one foot. North elevation along Arthington Street (then Harvard Street); only the first three floors were built at that time. NORTH ELEVATION - ANNEX B - Sears Roebuck & Company Mail Order Plant, Merchandise Building, 924 South Homan Avenue, Chicago, Cook County, IL
Assimilation of Wave and Current Data for Prediction of Inlet and River Mouth Dynamics
2013-07-01
onto the Delft3D computational grid and the specification of Riemann -type boundary conditions for the boundary-normal velocity and surface elevation...conditions from time- history data from in situ tide gages. The corrections are applied to the surface-elevation contribution to the Riemann boundary...The algorithms described above are all of the strong-constraint variational variety, and make use of adjoint solvers corresponding to the various
NASA Astrophysics Data System (ADS)
Meier, I.; Phillips, R.
2012-12-01
The stimulatory effect of elevated atmospheric CO2 under global climate change on forest productivity has been predicted to decrease over time as pools of available N in soil become depleted, but empirical support for such progressive N limitation has been lacking. Increased N acquisition from soil depleted in inorganic nitrogen requires stimulation of the microbial processing of organic N, possibly through increasing C supply to soil by plant roots or mycorrhizal hyphae. Increases in (mycorr)rhizosphere C fluxes could stimulate microbes to produce extra-cellular enzymes that release N from SOM, feeding back from soil microsites to ecosystem-scale processes. We investigated the influence of elevated CO2 on root exudation and soil enzyme activity at the Duke Forest FACE site, USA, where loblolly pine (Pinus taeda L.) stands have been exposed to elevated CO2 for 14 years and N fertilization for five years. In each plot, root boxes containing acetate windows were installed in 2008. Two years after installation, we collected soils adjacent to root tips (the rhizosphere), hyphal tips (the hyphosphere) and bulk soil. We measured in situ root exudation rates from intact pine roots. Study objectives were to analyze (i) the influence of atmospheric CO2 on root exudation and extra-cellular enzyme activities, (ii) the influence of soil N availability in regulating these activities, and (iii) the relationship between the activities of enzymes involved in N cycling in soils and gross N transformations at soil microsites. Elevated atmospheric CO2 significantly increased the activity of β-1-4-N-acetylglucosaminidase (NAG) in the rhizosphere by almost 2.5 times (39 to 95 nmol h-1 g-1), and 1.6fold in the hyphosphere relative to ambient plots. NAG is an enzyme involved in the degradation of chitin from the cell walls of soil organisms, releasing absorbable forms of nitrogen. The activity of peroxidase, which degrades aromatic C compounds of SOM, increased significantly in the hyphosphere of stands exposed to elevated CO2. Nitrogen fertilization diminished this effect of elevated CO2 on enzyme activities at microsites. Our results show that the metabolism of microbial communities is shifted to the decomposition of organic N under elevated atmospheric CO2, presumably stimulated by N limitation and increased root C exudation.
NASA Astrophysics Data System (ADS)
Mouratidis, Antonios
2013-04-01
Digital Elevation Models (DEMs) are an inherently interdisciplinary topic, both due to their production and validation methods, as well as their significance for numerous disciplines. The most utilized contemporary topographic datasets worldwide are those of global DEMs. Several space-based sources have been used for the production of (almost) global DEMs, namely satellite Synthetic Aperture Radar (SAR) Interferometry/InSAR, stereoscopy of multispectral satellite images and altimetry, producing several versions of autonomous or mixed products (i.e. SRTM, ACE, ASTER-GDEM). Complementary space-based observations, such as those of Global Navigation Satellite Systems (GNSS), are also used, mainly for validation purposes. The apparent positive impact of these elevation datasets so far has been consolidated by the plethora of related scientific, civil and military applications. Topography is a prominent element for almost all Earth sciences, but in Geomorphology it is even more fundamental. In geomorphological studies, elevation data and thus DEMs can be extensively used for the extraction of both qualitative and quantitative information, such as relief classification, determination of slope and slope orientation, delineation of drainage basins, extraction of drainage networks and much more. Global DEMs are constantly becoming finer, i.e. of higher spatial resolution and more "sensitive" to elevation changes, i.e. of higher vertical accuracy and these progresses are undoubtedly considered as a major breakthrough, each time a new improved global DEM is released. Nevertheless, for Geomorphology in particular, if not already there, we are close to the point in time, where the need for discrimination between DSM (Digital Surface Model) and DTM (Digital Terrain Model) is becoming critical; if the distinction between vegetation and man-made structures on one side (DSM), and actual terrain elevation on the other side (DTM) cannot be made, then, in many cases, any further increase of elevation accuracy in DEMs will have little impact on geomorphological studies. After shortly reviewing the evolution of satellite-based global DEMs, the purpose of this paper is to address their current limitations and challenges from the perspective of a geomorphologist. Subsequently, the implications for geomorphological studies are discussed, with respect to the expected near-future advances in the field, such as the TanDEM-X Global Digital Elevation Model ("WorldDEM", 2014), as well as spaceborne LIDAR (Light Detection and Ranging) approaches (e.g. Lidar Surface Topography/LIST mission, 2016-2020).
Increases in desert shrub productivity under elevated carbon dioxide vary with water availability
Housman, D.C.; Naumburg, E.; Huxman, T. E.; Charlet, T.N.; Nowak, R.S.; Smith, S.D.
2006-01-01
Productivity of aridland plants is predicted to increase substantially with rising atmospheric carbon dioxide (CO2) concentrations due to enhancement in plant water-use efficiency (WUE). However, to date, there are few detailed analyses of how intact desert vegetation responds to elevated CO2. From 1998 to 2001, we examined aboveground production, photosynthesis, and water relations within three species exposed to ambient (around 38 Pa) or elevated (55 Pa) CO2 concentrations at the Nevada Desert Free-Air CO2 Enrichment (FACE) Facility in southern Nevada, USA. The functional types sampled - evergreen (Larrea tridentata), drought-deciduous (Ambrosia dumosa), and winter-deciduous shrubs (Krameria erecta) - represent potentially different responses to elevated CO2 in this ecosystem. We found elevated CO2 significantly increased aboveground production in all three species during an anomalously wet year (1998), with relative production ratios (elevated:ambient CO2) ranging from 1.59 (Krameria) to 2.31 (Larrea). In three below-average rainfall years (1999-2001), growth was much reduced in all species, with only Ambrosia in 2001 having significantly higher production under elevated CO2. Integrated photosynthesis (mol CO2 m-2 y-1) in the three species was 1.26-2.03-fold higher under elevated CO2 in the wet year (1998) and 1.32-1.43-fold higher after the third year of reduced rainfall (2001). Instantaneous WUE was also higher in shrubs grown under elevated CO2. The timing of peak canopy development did not change under elevated CO2; for example, there was no observed extension of leaf longevity into the dry season in the deciduous species. Similarly, seasonal patterns in CO2 assimilation did not change, except for Larrea. Therefore, phenological and physiological patterns that characterize Mojave Desert perennials - early-season lags in canopy development behind peak photosynthetic capacity, coupled with reductions in late-season photosynthetic capacity prior to reductions in leaf area - were not significantly affected by elevated CO2. Together, these findings suggest that elevated CO2 can enhance the productivity of Mojave Desert shrubs, but this effect is most pronounced during years with abundant rainfall when soil resources are most available. ?? 2006 Springer Science+Business Media, Inc.
A method on error analysis for large-aperture optical telescope control system
NASA Astrophysics Data System (ADS)
Su, Yanrui; Wang, Qiang; Yan, Fabao; Liu, Xiang; Huang, Yongmei
2016-10-01
For large-aperture optical telescope, compared with the performance of azimuth in the control system, arc second-level jitters exist in elevation under different speeds' working mode, especially low-speed working mode in the process of its acquisition, tracking and pointing. The jitters are closely related to the working speed of the elevation, resulting in the reduction of accuracy and low-speed stability of the telescope. By collecting a large number of measured data to the elevation, we do analysis on jitters in the time domain, frequency domain and space domain respectively. And the relation between jitter points and the leading speed of elevation and the corresponding space angle is concluded that the jitters perform as periodic disturbance in space domain and the period of the corresponding space angle of the jitter points is 79.1″ approximately. Then we did simulation, analysis and comparison to the influence of the disturbance sources, like PWM power level output disturbance, torque (acceleration) disturbance, speed feedback disturbance and position feedback disturbance on the elevation to find that the space periodic disturbance still exist in the elevation performance. It leads us to infer that the problems maybe exist in angle measurement unit. The telescope employs a 24-bit photoelectric encoder and we can calculate the encoder grating angular resolution as 79.1016'', which is as the corresponding angle value in the whole encoder system of one period of the subdivision signal. The value is approximately equal to the space frequency of the jitters. Therefore, the working elevation of the telescope is affected by subdivision errors and the period of the subdivision error is identical to the period of encoder grating angular. Through comprehensive consideration and mathematical analysis, that DC subdivision error of subdivision error sources causes the jitters is determined, which is verified in the practical engineering. The method that analyze error sources from time domain, frequency domain and space domain respectively has a very good role in guiding to find disturbance sources for large-aperture optical telescope.
Caffeine accelerates recovery from general anesthesia via multiple pathways.
Fong, Robert; Khokhar, Suhail; Chowdhury, Atif N; Xie, Kelvin G; Wong, Josiah Hiu-Yuen; Fox, Aaron P; Xie, Zheng
2017-09-01
Various studies have explored different ways to speed emergence from anesthesia. Previously, we have shown that three drugs that elevate intracellular cAMP (forskolin, theophylline, and caffeine) accelerate emergence from anesthesia in rats. However, our earlier studies left two main questions unanswered. First, were cAMP-elevating drugs effective at all anesthetic concentrations? Second, given that caffeine was the most effective of the drugs tested, why was caffeine more effective than forskolin since both drugs elevate cAMP? In our current study, emergence time from anesthesia was measured in adult rats exposed to 3% isoflurane for 60 min. Caffeine dramatically accelerated emergence from anesthesia, even at the high level of anesthetic employed. Caffeine has multiple actions including blockade of adenosine receptors. We show that the selective A 2a adenosine receptor antagonist preladenant or the intracellular cAMP ([cAMP] i )-elevating drug forskolin, accelerated recovery from anesthesia. When preladenant and forskolin were tested together, the effect on anesthesia recovery time was additive indicating that these drugs operate via different pathways. Furthermore, the combination of preladenant and forskolin was about as effective as caffeine suggesting that both A 2A receptor blockade and [cAMP] i elevation play a role in caffeine's ability to accelerate emergence from anesthesia. Because anesthesia in rodents is thought to be similar to that in humans, these results suggest that caffeine might allow for rapid and uniform emergence from general anesthesia in humans at all anesthetic concentrations and that both the elevation of [cAMP] i and adenosine receptor blockade play a role in this response. NEW & NOTEWORTHY Currently, there is no method to accelerate emergence from anesthesia. Patients "wake" when they clear the anesthetic from their systems. Previously, we have shown that caffeine can accelerate emergence from anesthesia. In this study, we show that caffeine is effective even at high levels of anesthetic. We also show that caffeine operates by both elevating intracellular cAMP levels and by blocking adenosine receptors. This complicated pharmacology makes caffeine especially effective in accelerating emergence from anesthesia. Copyright © 2017 the American Physiological Society.
Troponin T elevation after permanent pacemaker implantation.
Chen, Xueying; Yu, Ziqing; Bai, Jin; Hu, Shulan; Wang, Wei; Qin, Shengmei; Wang, Jingfeng; Sun, Zhe; Su, Yangang; Ge, Junbo
2017-08-01
The objective of the study is to study the incidence, significance, and factors associated with cardiac troponin T (CTNT) elevation after pacemaker implantation. Three hundred seventy-four patients (104 single-chamber pacemakers or ICD, 243 dual-chamber pacemakers, and 27 cardiac resynchronization therapy/cardiac resynchronization therapy defibrillator) who had normal levels of CTNT at baseline and underwent implantation of a permanent pacemaker system were included in this study. Serum levels of CTNT were measured at baseline, 6 and 24 h after the implantation procedure. The median of CTNT levels increased from 0.012 ng/mL at baseline to 0.032 and 0.019 ng/mL at 6 and 24 h after the procedure, respectively (all p < 0.0001). Elevated CTNT levels were noted in 208 patients (55.6%) at 6 h after the implantation, among which 29 patients (7.8%) had CTNT levels exceeding the range of minimal myocardial damage (>0.09 ng/mL). After 1-year follow-up, the incidence of complications including dislodgement of the lead, pocket infection, pneumothorax, hemothorax, and vein thrombus and cardiac outcomes including hospitalization of heart failure, coronary artery disease, arrhythmia, and cardiovascular mortality was not significantly different between the normal and elevated CTNT groups at 6 h after the procedure. By logistic regression analysis, gender, N-terminal pro-B type natriuretic peptide (NT-pro-BNP) at baseline, left ventricular ejection fractions (LVEF), estimated glomerular filtration rate (eGFR), and fluoroscopy time were independently associated with CTNT elevation after adjusted for age, pacemaker types, right ventricle lead location (RVA or RVOT), heart function, and left ventricular end systolic dimension. Pacemaker implantation was found to be accompanied with CTNT elevation in 55.6% of the patients at 6 h after the procedure, and its kinetics were fast, which might not be related to the complications and adverse cardiac outcomes within 1 year of follow-up. Moreover, gender, NT-pro-BNP at baseline, LVEF, eGFR, and fluoroscopy time were found to be independent predictors of CTNT elevation.
NASA Astrophysics Data System (ADS)
Martin, C.
2017-12-01
Topography can be used to delineate streams and quantify the topographic control on hydrological processes of a watershed because geomorphologic processes have shaped the topography and streams of a catchment over time. Topographic Wetness index (TWI) is a common index used for delineating stream networks by predicting location of saturation excess overland flow, but is also used for other physical attributes of a watershed such as soil moisture, groundwater level, and vegetation patterns. This study evaluates how well TWI works across an elevation gradient and the relationships between the active drainage network of four headwater watersheds at various elevations in the Colorado Front Range to topography, geology, climate, soils, elevation, and vegetation in attempt to determine the controls on streamflow location and duration. The results suggest that streams prefer to flow along a path of least resistance which including faults and permeable lithology. Permeable lithologies created more connectivity of stream networks during higher flows but during lower flows dried up. Streams flowing over impermeable lithologies had longer flow duration. Upslope soil hydraulic conductivity played a role on stream location, where soils with low hydraulic conductivity had longer flow duration than soils with higher hydraulic conductivity.Finally TWI thresholds ranged from 5.95 - 10.3 due to changes in stream length and to factors such as geology and soil. TWI had low accuracy for the lowest elevation site due to the greatest change of stream length. In conclusion, structural geology, upslope soil texture, and the permeability of the underlying lithology influenced where the stream was flowing and for how long. Elevation determines climate which influences the hydrologic processes occurring at the watersheds and therefore affects the duration and timing of streams at different elevations. TWI is an adequate tool for delineating streams because results suggest topography has a primary control on the stream locations, but because intermittent streams change throughout the year a algorithm needs to be created to correspond to snow melt and rain events. Also geology indices and soil indices need be considered in addition to topography to have the most accurate derived stream network.
Ofek, Fanny; Bar Chaim, Samuel; Kronenfeld, Nirit; Ziv-Baran, Tomer; Berkovitch, Matitiahu
2017-05-01
Direct factor Xa inhibitors such as rivaroxaban or apixaban may prolong prothrombin time (PT) and elevate international normalized ratio (INR). However, these tests are not reliable for assessing the anticoagulation effects of these agents. PT assay sensitivity is relatively weak at therapeutic drug concentrations and is subjected to significant variations depending on the reagent used. Conversion of PT to INR may even increase the variability. We conducted a retrospective cross-sectional study aiming to assess the prevalence and extent of INR elevation in hospitalized patients receiving rivaroxaban or apixaban as part of their home medications and to find out whether other existing factors could elevate INR apart from the drug entity itself. The data collected from 218 hospitalized patients׳ charts included PT and INR taken on admission, patients׳ characteristics, laboratory results, other medications regularly used, and coexisting clinical conditions. No statistically significant association between INR elevation and the parameters examined was found in our study. INR was significantly elevated in both drug groups (P < 0.001), with 84.2% of rivaroxaban patients and 78.3% of apixaban patients presenting with INR levels above the higher limit of the normal range. Furthermore, INR was significantly higher in the rivaroxaban group than in the apixaban group (P < 0.001). Both of the reviewed drugs significantly elevated INR. Moreover, rivaroxaban elevates INR significantly more than apixaban, and there are apparently no other factors affecting INR but the drugs themselves. Larger prospective studies are needed to confirm and clarify the clinical significance of these results. Copyright © 2017 Elsevier HS Journals, Inc. All rights reserved.
NASA Astrophysics Data System (ADS)
Yamanaka, T.; Sato, R.
2017-12-01
Transpiration (T) through plants (i.e., green water) does not induce isotopic fractionation, although evaporation (E) from soils and water surfaces do. Therefore, water stable isotopes offer a powerful tool to partition evapotranspiration (ET) components. We attempted to evaluate catchment-scale T/ET for five mountainous catchments in the central Japan, using river water isotopes and isotope maps of precipitation and soil water as well as climatic and radar precipitation maps. The estimated T/ET ranged from 56% to 79% (ET not including interception loss), and negatively correlated with mean elevation of the catchments (r = -0.88). This is due to decreasing transpiration (-82 mm/yr per 100 m) and slightly increasing evaporation (8 mm/yr per 100 m) with increasing elevation. Another estimation scheme using isotope data only showed a positive correlation between elevation and E/P*, where P* is effective precipitation defined by gross precipitation minus interception. Because the forest coverage within the catchments has positive correlation with catchment-mean-elevation, both decrease in transpiration and increase in soil evaporation seem to reflect structural change in forests (e.g., dense to sparse) along elevation and thus temperature gradients. Applying the space-for-time substitution, our results indicates that global warming will increase transpiration (and thus carbon intake) at mid-latitude mountainous landscapes.
Liu, Xin; Han, Yanqing; Zhu, Jinge; Deng, Jiancai; Hu, Weiping; da Silva, Thomaz Edson Veloso
2018-01-01
The growth of most submerged macrophytes is likely to be limited by the availability of carbon resource, and this is especially true for the obligatory carbon dioxide (CO 2 ) users. A mesocosm experiment was performed to investigate the physiological, photophysiological, and biochemical responses of Cabomba caroliniana, an invasive macrophyte specie in the Lake Taihu Basin, to elevated atmospheric CO 2 (1000 μmol mol -1 ); we also examined the possible impacts of interferences derived from the phytoplankton proliferation and its concomitant disturbances on the growth of C. caroliniana. The results demonstrated that elevated atmospheric CO 2 significantly enhanced the biomass, relative growth rate, and photosynthate accumulation of C. caroliniana. C. caroliniana exposed to elevated atmospheric CO 2 exhibited a higher relative maximum electron transport rate and photosynthetic efficiency, compared to those exposed to ambient atmospheric CO 2 . However, the positive effects of elevated atmospheric CO 2 on C. caroliniana were gradually compromised as time went by, and the down-regulations of the relative growth rate (RGR) and photosynthetic activity were coupled with phytoplankton proliferation under elevated atmospheric CO 2 . This study demonstrated that the growth of C. caroliniana under the phytoplankton interference can be greatly affected, directly and indirectly, by the increasing atmospheric CO 2 .
DOE Office of Scientific and Technical Information (OSTI.GOV)
Sherman, F
1958-11-01
A comparative study was made of the growth of yeast in various media at the optimum temperature (30 ) and at supraoptimum temperatures. It was found that at elevated temperatures there is a decrease in the ability of yeast to grow, which may be alleviated by increasing the percentage of yeast extract in the medium, adding oleic acid to the medium, or using an inoculum of cells that have previously been grown at the elevated temperature. Because of these findings, it is believed that growth at elevated temperatures results in an increased nutrient requirement which may be eliminated by inducedmore » adaptation. When yeasts were grown at elevated temperatures or exposed for a short time to lethal temperatures it was found that there was a great increase in the fraction of respiratory-deficient mutants (petites). It was shown that the increase of mutants did not arise because of selection, but that the elevated temperatures actually induced the mutation. From the results of various genetic analyses it is shown that these respiratorydeficient mutants are very similar, if not identical. to vegetative petites occurring spontaneously or induced by acriflavine. The kinetics of this mutation is discussed, with possible theoretical interpretations. (auth)« less
The Effect of Elevated CO2 and Temperature on the Hatch Rate and Survival of Estuarine Forage Fish
NASA Astrophysics Data System (ADS)
Merlo, L. R.; Gobler, C.
2016-02-01
The World Oceans are acidifying and warming, yet little is known regarding how these processes will combine to impact fish populations. In estuaries, microbial respiration of eutrophication-enhanced organic matter can create elevated CO2 levels during late spring and summer seasons when thermal extremes can occur and temperate fish spawn. Here, we report on experiments that exposed fish embryos (e.g. Menidia beryllina, inland silverside) to normal and elevated CO2 (400 and 2,000 ppm) and the range of temperatures experienced within temperate estuaries during the spawning season (16 - 30C). Fish survival and growth rates were quantified from hatching through early life, larval stages. Temperature controlled egg hatching times, with elevated temperatures leading to more rapid hatch rates. Elevated levels of CO2 significantly depressed post-hatch survival of fish. Survival rates of fish exposed to elevated CO2 at lower than ideal temperatures were significantly lower than predicted by either variable individually indicating the ability of these stressors to synergistically interact. Since embryonic stages have been identified as being highly sensitive to acidification, this finding may be associated with the extended exposure of eggs to high CO2 at lower temperatures. The physiological mechanisms driving experimental trends and broader ecological implications of the study will be discussed.
Plant growth in elevated CO2 alters mitochondrial number and chloroplast fine structure
Griffin, Kevin L.; Anderson, O. Roger; Gastrich, Mary D.; Lewis, James D.; Lin, Guanghui; Schuster, William; Seemann, Jeffrey R.; Tissue, David T.; Turnbull, Matthew H.; Whitehead, David
2001-01-01
With increasing interest in the effects of elevated atmospheric CO2 on plant growth and the global carbon balance, there is a need for greater understanding of how plants respond to variations in atmospheric partial pressure of CO2. Our research shows that elevated CO2 produces significant fine structural changes in major cellular organelles that appear to be an important component of the metabolic responses of plants to this global change. Nine species (representing seven plant families) in several experimental facilities with different CO2-dosing technologies were examined. Growth in elevated CO2 increased numbers of mitochondria per unit cell area by 1.3–2.4 times the number in control plants grown in lower CO2 and produced a statistically significant increase in the amount of chloroplast stroma (nonappressed) thylakoid membranes compared with those in lower CO2 treatments. There was no observable change in size of the mitochondria. However, in contrast to the CO2 effect on mitochondrial number, elevated CO2 promoted a decrease in the rate of mass-based dark respiration. These changes may reflect a major shift in plant metabolism and energy balance that may help to explain enhanced plant productivity in response to elevated atmospheric CO2 concentrations. PMID:11226263
NASA Technical Reports Server (NTRS)
Deau, E. A.; Spilker, L. J.; Morishima, R.; Brooks, S.; Pilorz, S.; Altobelli, N.
2011-01-01
After more than six years in orbit around Saturn, the Cassini Composite Infrared Spectrometer (CIRS) has acquired an extensive set of measurements of Saturn's main rings (A, B, C and Cassini Division) in the thermal infrared. Temperatures were retrieved for the lit and unlit rings over a variety of ring geometries that include phase angle, solar and spacecraft elevations and local time. We show that some of these parameters (solar and spacecraft elevations, phase angle) play a role in the temperature variations in the first order, while the others (ring and particle local time) produced second order effects. The results of this comparison will be presented.
Removing tidal-period variations from time-series data using low-pass digital filters
Walters, Roy A.; Heston, Cynthia
1982-01-01
Several low-pass, digital filters are examined for their ability to remove tidal Period Variations from a time-series of water surface elevation for San Francisco Bay. The most efficient filter is the one which is applied to the Fourier coefficients of the transformed data, and the filtered data recovered through an inverse transform. The ability of the filters to remove the tidal components increased in the following order: 1) cosine-Lanczos filter, 2) cosine-Lanczos squared filter; 3) Godin filter; and 4) a transform fitter. The Godin fitter is not sufficiently sharp to prevent severe attenuation of 2–3 day variations in surface elevation resulting from weather events.
[Acute myocardial infarction with ST-segment elevation: Code I].
Borrayo-Sánchez, Gabriela; Rosas-Peralta, Martín; Pérez-Rodríguez, Gilberto; Ramírez-Árias, Erick; Almeida-Gutiérrez, Eduardo; Arriaga-Dávila, José de Jesús
2018-01-01
Code infarction is a timely strategy for the treatment of acute myocardial infarction (AMI) with elevation of the ST segment. This strategy has shown an increase in survival and quality of life of patients suffering from this event around the world. The processes of management and disposition aimed at the reduction of time for effective and timely reperfusion are undoubtedly a continuous challenge. In the Instituto Mexicano del Seguro Social (IMSS) the mortality due to AMI has been reduced more than 50%, which is a historical situation that deserves much attention. Nonetheless, the continuous improvement and a wider coverage of this strategy in our country are the key factors that will outline a change in the natural history of the leading cause of death in Mexico. This review focuses on current strategies for the management of patients with acute myocardial infarction.
NASA Astrophysics Data System (ADS)
Mishra, N. B.; Mainali, K. P.
2016-12-01
Climatic changes along with anthropogenic disturbances are causing dramatic ecological impacts in mid to high latitude mountain vegetation including in the Himalayas which are ecologically sensitive environments. Given the challenges associated with in situ vegetation monitoring in the Himalayas, remote sensing based quantification of vegetation dynamics can provide essential ecological information on changes in vegetation activity that may consist of alternative sequence of greening and/or browning periods. This study utilized a trend break analysis procedure for detection of monotonic as well as abrupt (either interruption or reversal) trend changes in smoothed normalized difference vegetation index satellite time-series data over the Himalayas. Overall, trend breaks in vegetation greenness showed high spatio-temporal variability in distribution considering elevation, ecoregion and land cover/use stratifications. Interrupted greening was spatially most dominant in all Himalayan ecoregions followed by abrupt browning. Areas showing trend reversal and monotonic trends appeared minority. Trend type distribution was strongly dependent on elevation as majority of greening (with or without interruption) occurred at lower elevation areas at higher elevation were dominantly. Ecoregion based stratification of trend types highlighted some exception to this elevational dependence as high altitude ecoregions of western Himalayas showed significantly less browning compared to the ecoregions in eastern Himalaya. Land cover/use based analysis of trend distribution showed that interrupted greening was most dominant in closed needleleafed forest following by rainfed cropland and mosaic croplands while interrupted browning most dominant in closed to open herbaceous vegetation found at higher elevation areas followed by closed needleleafed forest and closed to open broad leafed evergreen forests. Spatial analysis of trend break timing showed that for majority of areas experiencing interrupted greening, break in trend occurred later compared to areas with interrupted browning where break trend was observed much earlier. These results have significant implications for environmental management in the context of climate change and ecosystem dynamics in the Himalayas.
Sidana, Abhinav; Walton-Diaz, Annerleim; Truong, Hong; Siddiqui, M Minhaj; Miao, Ning; Shih, Johanna; Mannes, Andrew; Bratslavsky, Gennady; Linehan, W Marston; Metwalli, Adam R
2016-07-01
To identify the risk factors associated with development of postoperative elevation of creatine kinase (CK) and study its effect on renal function in patients who underwent complex multifocal partial nephrectomy (PN). Patients who underwent PN at National Cancer Institute between January 2007 and December 2012 were included in the study. Elevated serum CK was defined as >2000 U/L. Kidney function was assessed using serum creatinine and estimated glomerular filtration rate (eGFR). Changes were reported as percent change from preoperative values and compared using the Wilcoxon test. Regression analysis was performed to identify the predictors of elevation in CK and decline in eGFR. From 407 total cases, 207 had adequate CK data for analysis. Median number of tumors removed was 3 (1-70). Median peak CK was 1458 (82-36,788). Forty-two percent developed CK elevation >2000 U/L. Factors associated with postoperative elevation of CK > 2000 were young age (p = 0.009), high BMI (p = 0.003) and operating room time (p < 0.001). Although CK > 2000 was associated with significantly greater decline in eGFR (37.4 vs. 20.3 %, p < 0.001) in immediate postoperative period, this change largely resolved to a much less clinically relevant (9.2 vs 3.3 %, p = 0.040) change after 3 months. On multivariate analysis, postoperative elevation in CK was not found to be an independent factor determining renal function at 3 months. In our cohort, a significant proportion of patients developed CK elevations >2000 U/L. While patients with elevated CK had more decline in eGFR in immediate postoperative period, postoperative elevations of CK did not appear to impact overall long-term renal function in patients undergoing PN.
Elevated Temperature and CO2 Stimulate Late-Season Photosynthesis But Impair Cold Hardening in Pine.
Chang, Christine Y; Fréchette, Emmanuelle; Unda, Faride; Mansfield, Shawn D; Ensminger, Ingo
2016-10-01
Rising global temperature and CO 2 levels may sustain late-season net photosynthesis of evergreen conifers but could also impair the development of cold hardiness. Our study investigated how elevated temperature, and the combination of elevated temperature with elevated CO 2 , affected photosynthetic rates, leaf carbohydrates, freezing tolerance, and proteins involved in photosynthesis and cold hardening in Eastern white pine (Pinus strobus). We designed an experiment where control seedlings were acclimated to long photoperiod (day/night 14/10 h), warm temperature (22°C/15°C), and either ambient (400 μL L -1 ) or elevated (800 μmol mol -1 ) CO 2 , and then shifted seedlings to growth conditions with short photoperiod (8/16 h) and low temperature/ambient CO 2 (LTAC), elevated temperature/ambient CO 2 (ETAC), or elevated temperature/elevated CO 2 (ETEC). Exposure to LTAC induced down-regulation of photosynthesis, development of sustained nonphotochemical quenching, accumulation of soluble carbohydrates, expression of a 16-kD dehydrin absent under long photoperiod, and increased freezing tolerance. In ETAC seedlings, photosynthesis was not down-regulated, while accumulation of soluble carbohydrates, dehydrin expression, and freezing tolerance were impaired. ETEC seedlings revealed increased photosynthesis and improved water use efficiency but impaired dehydrin expression and freezing tolerance similar to ETAC seedlings. Sixteen-kilodalton dehydrin expression strongly correlated with increases in freezing tolerance, suggesting its involvement in the development of cold hardiness in P. strobus Our findings suggest that exposure to elevated temperature and CO 2 during autumn can delay down-regulation of photosynthesis and stimulate late-season net photosynthesis in P. strobus seedlings. However, this comes at the cost of impaired freezing tolerance. Elevated temperature and CO 2 also impaired freezing tolerance. However, unless the frequency and timing of extreme low-temperature events changes, this is unlikely to increase risk of freezing damage in P. strobus seedlings. © 2016 American Society of Plant Biologists. All Rights Reserved.
2016-01-01
Rising global temperature and CO2 levels may sustain late-season net photosynthesis of evergreen conifers but could also impair the development of cold hardiness. Our study investigated how elevated temperature, and the combination of elevated temperature with elevated CO2, affected photosynthetic rates, leaf carbohydrates, freezing tolerance, and proteins involved in photosynthesis and cold hardening in Eastern white pine (Pinus strobus). We designed an experiment where control seedlings were acclimated to long photoperiod (day/night 14/10 h), warm temperature (22°C/15°C), and either ambient (400 μL L−1) or elevated (800 μmol mol−1) CO2, and then shifted seedlings to growth conditions with short photoperiod (8/16 h) and low temperature/ambient CO2 (LTAC), elevated temperature/ambient CO2 (ETAC), or elevated temperature/elevated CO2 (ETEC). Exposure to LTAC induced down-regulation of photosynthesis, development of sustained nonphotochemical quenching, accumulation of soluble carbohydrates, expression of a 16-kD dehydrin absent under long photoperiod, and increased freezing tolerance. In ETAC seedlings, photosynthesis was not down-regulated, while accumulation of soluble carbohydrates, dehydrin expression, and freezing tolerance were impaired. ETEC seedlings revealed increased photosynthesis and improved water use efficiency but impaired dehydrin expression and freezing tolerance similar to ETAC seedlings. Sixteen-kilodalton dehydrin expression strongly correlated with increases in freezing tolerance, suggesting its involvement in the development of cold hardiness in P. strobus. Our findings suggest that exposure to elevated temperature and CO2 during autumn can delay down-regulation of photosynthesis and stimulate late-season net photosynthesis in P. strobus seedlings. However, this comes at the cost of impaired freezing tolerance. Elevated temperature and CO2 also impaired freezing tolerance. However, unless the frequency and timing of extreme low-temperature events changes, this is unlikely to increase risk of freezing damage in P. strobus seedlings. PMID:27591187
Facilitating adaptation in montane plants to changing precipitation along an elevation gradient
Hess, Steve; Leopold, Christina
2017-01-01
Montane plant communities throughout the world have responded to changes in precipitation and temperature regimes by shifting ranges upward in elevation. Continued warmer, drier climate conditions have been documented and are projected to increase in high-elevation areas in Hawai‘i, consistent with climate change effects reported in other environments throughout the world. Organisms that cannot disperse or adapt biologically to projected climate scenarios in situ may decrease in distributional range and abundance over time. Restoration efforts will need to accommodate future climate change and account for the interactive effects of existing invasive species to ensure long-term persistence. As part of a larger, ongoing restoration effort, we hypothesized that plants from a lower-elevation forest ecotype would have higher rates of survival and growth compared to high-elevation forest conspecifics when grown in common plots along an elevation gradient. We monitored climate conditions at planting sites to identify whether temperature or rainfall influenced survival and growth after 20 weeks. We found that origin significantly affected survival in only one of three native montane species, Dodonaea viscosa. Contrary to our hypothesis, 75.2% of seedlings from high-elevation origin survived in comparison to 58.7% of seedlings from low elevation across the entire elevation gradient. Origin also influenced survival in linearized mixed models that controlled for temperature, precipitation, and elevation in D. viscosa and Chenopodium oahuense. Only C. oahuense seedlings had similar predictors of growth and survival. There were no common patterns of growth or survival between species, indicating that responses to changing precipitation and emperature regimes varied between montane plant species. Results also suggest that locally sourced seed is important to ensure highest survival at restoration sites. Further experimentation on larger spatial and temporal scales is necessary to determine the empirical responses of species and communities to changing climate in the full context of highly degraded Hawaiian ecosystems.
ICESat laser altimetry over small mountain glaciers
NASA Astrophysics Data System (ADS)
Treichler, Désirée; Kääb, Andreas
2016-09-01
Using sparsely glaciated southern Norway as a case study, we assess the potential and limitations of ICESat laser altimetry for analysing regional glacier elevation change in rough mountain terrain. Differences between ICESat GLAS elevations and reference elevation data are plotted over time to derive a glacier surface elevation trend for the ICESat acquisition period 2003-2008. We find spatially varying biases between ICESat and three tested digital elevation models (DEMs): the Norwegian national DEM, SRTM DEM, and a high-resolution lidar DEM. For regional glacier elevation change, the spatial inconsistency of reference DEMs - a result of spatio-temporal merging - has the potential to significantly affect or dilute trends. Elevation uncertainties of all three tested DEMs exceed ICESat elevation uncertainty by an order of magnitude, and are thus limiting the accuracy of the method, rather than ICESat uncertainty. ICESat matches glacier size distribution of the study area well and measures small ice patches not commonly monitored in situ. The sample is large enough for spatial and thematic subsetting. Vertical offsets to ICESat elevations vary for different glaciers in southern Norway due to spatially inconsistent reference DEM age. We introduce a per-glacier correction that removes these spatially varying offsets, and considerably increases trend significance. Only after application of this correction do individual campaigns fit observed in situ glacier mass balance. Our correction also has the potential to improve glacier trend significance for other causes of spatially varying vertical offsets, for instance due to radar penetration into ice and snow for the SRTM DEM or as a consequence of mosaicking and merging that is common for national or global DEMs. After correction of reference elevation bias, we find that ICESat provides a robust and realistic estimate of a moderately negative glacier mass balance of around -0.36 ± 0.07 m ice per year. This regional estimate agrees well with the heterogeneous but overall negative in situ glacier mass balance observed in the area.
ERIC Educational Resources Information Center
Barth, Roland S.
2013-01-01
"It's always been a promising time for teacher leadership. It's just never been a successful time," writes noted educator Roland Barth. Why? Barth points to five obstacles: administrator resistance, the taboo in teaching against elevating oneself higher than one's peers, the fact that teachers' plates are full, the…
Helicopter Airborne Laser Positioning System (HALPS)
NASA Technical Reports Server (NTRS)
Eppel, Joseph C.; Christiansen, Howard; Cross, Jeffrey; Totah, Joseph
1990-01-01
The theory of operation, configuration, laboratory, and ground test results obtained with a helicopter airborne laser positioning system developed by Princeton University is presented. Unfortunately, due to time constraints, flight data could not be completed for presentation at this time. The system measures the relative position between two aircraft in three dimensions using two orthogonal fan-shaped laser beams sweeping across an array of four detectors. Specifically, the system calculates the relative range, elevation, and azimuth between an observation aircraft and a test helicopter with a high degree of accuracy. The detector array provides a wide field of view in the presence of solar interference due to compound parabolic concentrators and spectral filtering of the detector pulses. The detected pulses and their associated time delays are processed by the electronics and are sent as position errors to the helicopter pilot who repositions the aircraft as part of the closed loop system. Accuracies obtained in the laboratory at a range of 80 ft in the absence of sunlight were + or - 1 deg in elevation; +0.5 to -1.5 deg in azimuth; +0.5 to -1.0 ft in range; while elevation varied from 0 to +28 deg and the azimuth varied from 0 to + or - 45 deg. Accuracies in sunlight were approximately 40 deg (+ or - 20 deg) in direct sunlight.
Behavioural adaptations of Rana temporaria to cold climates.
Ludwig, Gerda; Sinsch, Ulrich; Pelster, Bernd
2015-01-01
Environmental conditions at the edge of a species' ecological optimum can exert great ecological or evolutionary pressure at local populations. For ectotherms like amphibians temperature is one of the most important abiotic factors of their environment as it influences directly their metabolism and sets limits to their distribution. Amphibians have evolved three ways to cope with sub-zero temperatures: freeze tolerance, freeze protection, freeze avoidance. The aim of this study was to assess which strategy common frogs at mid and high elevation use to survive and thrive in cold climates. In particular we (1) tested for the presence of physiological freeze protection, (2) evaluated autumnal activity and overwintering behaviour with respect to freeze avoidance and (3) assessed the importance of different high-elevation microhabitats for behavioural thermoregulation. Common frogs did not exhibit any signs of freeze protection when experiencing temperatures around 0 °C. Instead they retreated to open water for protection and overwintering. High elevation common frogs remained active for around the same period of time than their conspecifics at lower elevation. Our results suggest that at mid and high elevation common frogs use freeze avoidance alone to survive temperatures below 0 °C. The availability of warm microhabitats, such as rock or pasture, provides high elevation frogs with the opportunity of behavioural thermoregulation and thus allows them to remain active at temperatures at which common frogs at lower elevation cease activity. Copyright © 2015 Elsevier Ltd. All rights reserved.
Rivers, Charles A.; Barton, James C.; Gordeuk, Victor R.; Acton, Ronald T.; Speechley, Mark R.; Snively, Beverly M.; Leiendecker-Foster, Catherine; Press, Richard D.; Adams, Paul C.; McLaren, Gordon D.; Dawkins, Fitzroy W.; McLaren, Christine E.; Reboussin, David M.
2007-01-01
The ferroportin (FPN1) Q248H polymorphism has been associated with increased serum ferritin (SF) levels in sub-Saharan Africans and in African Americans (AA). AA participants of the HEIRS Study who did not have HFE C282Y or H63D who had elevated initial screening SF (≥300 μg/L in men and ≥200 μg/L in women) (defined as cases) were frequency-matched to AA participants with normal SF (defined as controls) to investigate the association of the Q248H with elevated SF. 10.4% of cases and 6.7% of controls were Q248H heterozygotes (P = 0.257). Q248H homozygosity was observed in 0.5% of the cases and none of the controls. The frequency of Q248H was higher among men with elevated SF than among control men (P = 0.047); corresponding differences were not observed among women. This appeared to be unrelated to self-reports of a previous diagnosis of liver disease. Men with elevated SF were three times more likely than women with elevated SF to have Q248H (P = 0.012). There were no significant differences in Q248H frequencies in men and women control participants. We conclude that the frequency of the FPN1 Q248H polymorphism is greater in AA men with elevated SF than in those with normal SF. PMID:17276706
Brodsky, Arthur Nathan; Caldwell, Mary; Bae, Sooneon; Harcum, Sarah W.
2014-01-01
NS0 and Chinese hamster ovary (CHO) cell lines are used to produce recombinant proteins for human therapeutics; however, ammonium accumulation can negatively impact cell growth, recombinant protein production, and protein glycosylation. To improve product quality and decrease costs, the relationship between ammonium and protein glycosylation needs to be elucidated. While ammonium has been shown to adversely affect glycosylation-related gene expression in CHO cells, NS0 studies have not been performed. Therefore, this study sought to determine if glycosylation in NS0 cells were ammonium-sensitive at the gene expression level. Using a DNA microarray that contained mouse glycosylation-related and housekeeping genes, the of these genes was analysed in response to various culture conditions – elevated ammonium, elevated salt, and elevated ammonium with proline. Surprisingly, no significant differences in gene expression levels were observed between the control and these conditions. Further, the elevated ammonium cultures were analysed using real-time quantitative reverse transcriptase PCR (qRT-PCR) for key glycosylation genes, and the qRT-PCR results corroborated the DNA microarray results, demonstrating that NS0 cells are ammonium-insensitive at the gene expression level. Since NS0 are known to have elevated nucleotide sugar pools under ammonium stress, and none of the genes directly responsible for these metabolic pools were changed, consequently cellular control at the translational or substrate-level must be responsible for the universally observed decreased glycosylation quality under elevated ammonium. PMID:25062658
Multi Car Elevator Control by using Learning Automaton
NASA Astrophysics Data System (ADS)
Shiraishi, Kazuaki; Hamagami, Tomoki; Hirata, Hironori
We study an adaptive control technique for multi car elevators (MCEs) by adopting learning automatons (LAs.) The MCE is a high performance and a near-future elevator system with multi shafts and multi cars. A strong point of the system is that realizing a large carrying capacity in small shaft area. However, since the operation is too complicated, realizing an efficient MCE control is difficult for top-down approaches. For example, “bunching up together" is one of the typical phenomenon in a simple traffic environment like the MCE. Furthermore, an adapting to varying environment in configuration requirement is a serious issue in a real elevator service. In order to resolve these issues, having an autonomous behavior is required to the control system of each car in MCE system, so that the learning automaton, as the solutions for this requirement, is supposed to be appropriate for the simple traffic control. First, we assign a stochastic automaton (SA) to each car control system. Then, each SA varies its stochastic behavior distributions for adapting to environment in which its policy is evaluated with each passenger waiting times. That is LA which learns the environment autonomously. Using the LA based control technique, the MCE operation efficiency is evaluated through simulation experiments. Results show the technique enables reducing waiting times efficiently, and we confirm the system can adapt to the dynamic environment.
Prior irradiation results in elevated programmed cell death protein 1 (PD-1) in T cells.
Li, Deguan; Chen, Renxiang; Wang, Yi-Wen; Fornace, Albert J; Li, Heng-Hong
2018-05-01
In this study we addressed the question whether radiation-induced adverse effects on T cell activation are associated with alterations of T cell checkpoint receptors. Expression levels of checkpoint receptors on T cell subpopulations were analyzed at multiple post-radiation time points ranging from one to four weeks in mice receiving a single fraction of 1 or 4 Gy of γ-ray. T cell activation associated metabolic changes were assessed. Our results showed that prior irradiation resulted in significant elevated expression of programmed cell death protein 1 (PD-1) in both CD4+ and CD8+ populations, at all three post-radiation time points. T cells with elevated PD-1 mostly were either central memory or naïve cells. In addition, the feedback induction of PD-1 expression in activated T cells declined after radiation. Taken together, the elevated PD-1 level observed at weeks after radiation exposure is connected to T cell dysfunction. Recent preclinical and clinical studies have showed that a combination of radiotherapy and T cell checkpoint blockade immunotherapy including targeting the programmed death-ligand 1 (PD-L1)/PD-1 axis may potentiate the antitumor response. Understanding the dynamic changes in PD-1 levels in T cells after radiation should help in the development of a more effective therapeutic strategy.
Dalbøge, Annett; Frost, Poul; Andersen, Johan Hviid; Svendsen, Susanne Wulff
2018-03-01
We aimed to identify intensities of occupational mechanical exposures (force, arm elevation and repetition) that do not entail an increased risk of surgery for subacromial impingement syndrome (SIS) even after prolonged durations of exposure. Additionally, we wanted to evaluate if exposure to hand-arm vibration (HAV) is an independent risk factor. We used data from a register-based cohort study of the entire Danish working population (n=2 374 403). During follow-up (2003-2008), 14 118 first-time events of surgery for SIS occurred. For each person, we linked register-based occupational codes (1993-2007) to a general population job exposure matrix to obtain year-by-year exposure intensities on measurement scales for force, upper arm elevation >90° and repetition and expert rated intensities of exposure to HAV. For 10-year exposure time windows, we calculated the duration of exposure at specific intensities above minimal (low, medium and high). We used a logistic regression technique equivalent to discrete survival analysis adjusting for cumulative effects of other mechanical exposures. We found indications of safe exposure intensities for repetition (median angular velocity <45°/s), while force exertion ≥10% of maximal voluntary electrical activity and upper arm elevation >90° >2 min/day implied an increased risk reaching ORs of 1.7 and 1.5 after 10 years at low intensities. No associations were found for HAV. We found indications of safe exposure intensities for repetition. Any intensities of force and upper arm elevation >90° above minimal implied an increased risk across 10-year exposure time windows. No independent associations were found for HAV. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.
Wang, Mengmeng; Wang, Jilong; Sun, Hubo; Han, Sihai; Feng, Shuai; Shi, Lu; Meng, Peijun; Li, Jiayi; Huang, Peili; Sun, Zhiwei
2016-01-01
A complete understanding of the toxicological behavior of quantum dots (QDs) in vivo is of great importance and a prerequisite for their application in humans. In contrast with the numerous cytotoxicity studies investigating QDs, only a few in vivo studies of QDs have been reported, and the issue remains controversial. Our study aimed to understand QD-mediated toxicity across different time points and to explore the roles of free cadmium ions (Cd(2+)) and hydroxyl radicals (·OH) in tissue damage. Male ICR mice were administered a single intravenous dose (1.5 µmol/kg) of CdTe QDs, and liver and kidney function and morphology were subsequently examined at 1, 7, 14, and 28 days. Furthermore, ·OH production in the tissue was quantified by trapping · OH with salicylic acid (SA) as 2,3-dihydroxybenzoic acid (DHBA) and detecting it using a high-performance liquid chromatography fluorescence method. We used the induction of tissue metallothionein levels and 2,3-DHBA:SA ratios as markers for elevated Cd(2+) from the degradation of QDs and ·OH generation in the tissue, respectively. Our experimental results revealed that the QD-induced histopathological changes were time-dependent with elevated Cd(2+) and ·OH, and could recover after a period of time. The Cd(2+) and ·OH exhibited delayed effects in terms of histopathological abnormalities. Histological assessments performed at multiple time points might facilitate the evaluation of the biological safety of QDs.
Wang, Wei-Ping; Lou, Yan; Li, Zhen-Zhong; Li, Pan; Duan, Rui-Sheng
2007-02-01
SD rats were utilized for the purpose of the exploration of effects of status epilepticus (SE) on their emotional behavior, spatial learning and memory, and explorating its molecular mechanism. Forty maturity male SD rats, weighing (200 +/- 20) g were divided randomly and equally into SE group (SG) and normal control group (NG). The SG rats were induced by Pentylenetetrazole (PTZ) and the control animals received a saline (0.9%) solution. The change of emotional behavior in two groups were tested in elevated plus maze. Furthermore, Morris water maze was applied to evaluate the effects by SE on spatial learning and memory in rats. At the same time, N-methyl-D-aspartate (NMDA) receptor NR1 subunit mRNA in the hippocampus was determined by reverse transcription polymerase chain reaction (RT-PCR). In elevated plus test, SE rats increased the times of visits as well as the time spent on the open arms of the elevated plus maze (P < 0.01). In Morris water maze, the mean escape latency for the SE rats looking for hidden platform in the place navigation test prolonged (P < 0.01). The efficiency of their search strategy was poor (P < 0.05). The swimming time in platform region and the percentage of their swimming time decreased (P < 0.01). The number of times they crossed the platform area decreased (P < 0.01). Meanwhile the expression of NR1 subunit mRNA in hippocampus was lower (P < 0.01). The experimental results showed that SE could result in the change of emotional behavior and damage of spatial learning and memory in rats. NR1 might be involved in the patho- and physiological process in causing these behavioral changes.
Madsen, Lene H; Christensen, Geir; Lund, Terje; Serebruany, Victor L; Granger, Chris B; Hoen, Ingvild; Grieg, Zanina; Alexander, John H; Jaffe, Allan S; Van Eyk, Jennifer E; Atar, Dan
2006-11-10
Although measurement of troponin is widely used for diagnosing acute myocardial infarction (AMI), its diagnostic potential may be increased by a more complete characterization of its molecular appearance and degradation in the blood. The aim of this study was to define the time course of cardiac troponin I (cTnI) degradation in patients with acute ST-elevation myocardial infarction (STEMI). In the ASSENT-2 substudy, 26 males hospitalized with STEMI were randomized to 2 different thrombolytic drugs within 6 hours after onset of symptoms. Blood samples were obtained just before initiation of thrombolysis and at 30 minutes intervals (7 samples per patient). Western blot analysis was performed using anti-cTnI antibodies and compared with serum concentrations of cTnI. All patients exceeded the cTnI cutoff for AMI during the sampling period; at initiation of therapy, 23 had elevated cTnI values. All patients demonstrated 2 bands on immunoblot: intact cTnI and a single degradation product as early as 90 minutes after onset of symptoms. On subsequent samples, 15 of 26 patients showed multiple degradation products with up to 7 degradation bands. The appearance of fragments was correlated with higher levels of cTnI (P<0.001) and time to initiation of treatment (P=0.058). This study defines for the first time the initial time course of cTnI degradation in STEMI. Intact cTnI and a single degradation product were detectable on immunoblot as early as 90 minutes after onset of symptoms with further degradation after 165 minutes. Infarct size and time to initiation of treatment was the major determinant for degradation.
Montessori Preschool Elevates and Equalizes Child Outcomes: A Longitudinal Study.
Lillard, Angeline S; Heise, Megan J; Richey, Eve M; Tong, Xin; Hart, Alyssa; Bray, Paige M
2017-01-01
Quality preschool programs that develop the whole child through age-appropriate socioemotional and cognitive skill-building hold promise for significantly improving child outcomes. However, preschool programs tend to either be teacher-led and didactic, or else to lack academic content. One preschool model that involves both child-directed, freely chosen activity and academic content is Montessori. Here we report a longitudinal study that took advantage of randomized lottery-based admission to two public Montessori magnet schools in a high-poverty American city. The final sample included 141 children, 70 in Montessori and 71 in other schools, most of whom were tested 4 times over 3 years, from the first semester to the end of preschool (ages 3-6), on a variety of cognitive and socio-emotional measures. Montessori preschool elevated children's outcomes in several ways. Although not different at the first test point, over time the Montessori children fared better on measures of academic achievement, social understanding, and mastery orientation, and they also reported relatively more liking of scholastic tasks. They also scored higher on executive function when they were 4. In addition to elevating overall performance on these measures, Montessori preschool also equalized outcomes among subgroups that typically have unequal outcomes. First, the difference in academic achievement between lower income Montessori and higher income conventionally schooled children was smaller at each time point, and was not (statistically speaking) significantly different at the end of the study. Second, defying the typical finding that executive function predicts academic achievement, in Montessori classrooms children with lower executive function scored as well on academic achievement as those with higher executive function. This suggests that Montessori preschool has potential to elevate and equalize important outcomes, and a larger study of public Montessori preschools is warranted.
Kumar, Dinesh; Bhat, Zulfiqar Ali; Shah, M Y
2012-09-01
Angelica archangelica Linn. is widely used in food and liquor preparations and also in Kashmiri folk medicine to reduce anxiety. We evaluated the anxiolytic effect of successive extracts of A. archangelica linn. (SAE) on rats tested in the elevated T-maze test (an animal model of generalized anxiety) at doses that exhibit antidepressant-like activity in humans. A. archangelica (1 kg) was subjected to successive extraction in a soxhlet apparatus with solvents [petroleum ether (40-60 degrees C), chloroform, ethyl acetate, methanol and decoction with water] in order of increasing polarity (yield: 6.9%, 7.3%, 5.1%, 11.88% and 8.2% w/w, respectively). SAE were evaluated for anxiolytic effects using the elevated T-maze and forced swimming tests in rats. Oral dosing of diazepam (1 mg/kg) and extracts (50, 100 and 200 mg/kg) clearly showed an anxiolytic-like profile in the elevated T-maze test: it increased one-way escape and decreased inhibitory avoidance on the first, third and seventh day. In the forced swimming test, imipramine and SAE showed antidepressant- and anxiolytic-like effects as reflected by increased climbing time, swimming time and decreased immobility time on the first, third and seventh day. Aqueous and methanol extracts showed the most, petroleum ether (40-60 degrees C) and chloroform intermediate, and ethyl acetate the least anxiolytic activity (*P<0.05, **P<0.01, ***P< 0.001) in both models. These results suggest the anti-anxiety activity of various extracts of A. archangelica and strongly justify its use in traditional Indian medicine for the treatment of anxiety.
Roznik, Elizabeth A.; Alford, Ross A.
2015-01-01
One of the most devastating wildlife diseases ever recorded is chytridiomycosis, a recently emerged amphibian disease that is caused by the chytrid fungus Batrachochytrium dendrobatidis. Understanding, predicting, and managing the impacts of chytridiomycosis on any amphibian species will require detailed information on its ecology and behavior because this pathogen is transmitted by contact with water or other individuals, and pathogen growth rates are thermally sensitive. The common mistfrog (Litoria rheocola) is an endangered tropical rainforest frog that has declined due to chytridiomycosis. We tracked L. rheocola during the winter (cool/dry) and summer (warm/wet) seasons at a low- and high-elevation site. We found that seasonal differences in environmental temperatures and frog behavior should render this species most vulnerable to B. dendrobatidis during cooler months and at higher elevations, which matches observed patterns of infection prevalence in this species. During winter, frogs moved shorter distances than during summer, and they spent less time in vegetation and more time in the stream, which should increase exposure to aquatic B. dendrobatidis zoospores. At a low-elevation site (40 m ASL), estimated body temperatures were within the optimal range for B. dendrobatidis growth (15-25°C) most of the time during winter, but they reached temperatures above this threshold frequently in summer. At a higher elevation (750 m ASL), estimated body temperatures were within the range most favorable for B. dendrobatidis year-round, and did not exceed 25°C, even during summer. Our study provides the first detailed information on the ecology and behavior of L. rheocola and suggests ecological mechanisms for infection dynamics that have been observed in this endangered species. PMID:25993520
Roznik, Elizabeth A; Alford, Ross A
2015-01-01
One of the most devastating wildlife diseases ever recorded is chytridiomycosis, a recently emerged amphibian disease that is caused by the chytrid fungus Batrachochytrium dendrobatidis. Understanding, predicting, and managing the impacts of chytridiomycosis on any amphibian species will require detailed information on its ecology and behavior because this pathogen is transmitted by contact with water or other individuals, and pathogen growth rates are thermally sensitive. The common mistfrog (Litoria rheocola) is an endangered tropical rainforest frog that has declined due to chytridiomycosis. We tracked L. rheocola during the winter (cool/dry) and summer (warm/wet) seasons at a low- and high-elevation site. We found that seasonal differences in environmental temperatures and frog behavior should render this species most vulnerable to B. dendrobatidis during cooler months and at higher elevations, which matches observed patterns of infection prevalence in this species. During winter, frogs moved shorter distances than during summer, and they spent less time in vegetation and more time in the stream, which should increase exposure to aquatic B. dendrobatidis zoospores. At a low-elevation site (40 m ASL), estimated body temperatures were within the optimal range for B. dendrobatidis growth (15-25 °C) most of the time during winter, but they reached temperatures above this threshold frequently in summer. At a higher elevation (750 m ASL), estimated body temperatures were within the range most favorable for B. dendrobatidis year-round, and did not exceed 25 °C, even during summer. Our study provides the first detailed information on the ecology and behavior of L. rheocola and suggests ecological mechanisms for infection dynamics that have been observed in this endangered species.
Understanding the elevated suicide risk of female soldiers during deployments.
Street, A E; Gilman, S E; Rosellini, A J; Stein, M B; Bromet, E J; Cox, K L; Colpe, L J; Fullerton, C S; Gruber, M J; Heeringa, S G; Lewandowski-Romps, L; Little, R J A; Naifeh, J A; Nock, M K; Sampson, N A; Schoenbaum, M; Ursano, R J; Zaslavsky, A M; Kessler, R C
2015-03-01
The Army Study to Assess Risk and Resilience in Servicemembers (Army STARRS) has found that the proportional elevation in the US Army enlisted soldier suicide rate during deployment (compared with the never-deployed or previously deployed) is significantly higher among women than men, raising the possibility of gender differences in the adverse psychological effects of deployment. Person-month survival models based on a consolidated administrative database for active duty enlisted Regular Army soldiers in 2004-2009 (n = 975,057) were used to characterize the gender × deployment interaction predicting suicide. Four explanatory hypotheses were explored involving the proportion of females in each soldier's occupation, the proportion of same-gender soldiers in each soldier's unit, whether the soldier reported sexual assault victimization in the previous 12 months, and the soldier's pre-deployment history of treated mental/behavioral disorders. The suicide rate of currently deployed women (14.0/100,000 person-years) was 3.1-3.5 times the rates of other (i.e. never-deployed/previously deployed) women. The suicide rate of currently deployed men (22.6/100,000 person-years) was 0.9-1.2 times the rates of other men. The adjusted (for time trends, sociodemographics, and Army career variables) female:male odds ratio comparing the suicide rates of currently deployed v. other women v. men was 2.8 (95% confidence interval 1.1-6.8), became 2.4 after excluding soldiers with Direct Combat Arms occupations, and remained elevated (in the range 1.9-2.8) after adjusting for the hypothesized explanatory variables. These results are valuable in excluding otherwise plausible hypotheses for the elevated suicide rate of deployed women and point to the importance of expanding future research on the psychological challenges of deployment for women.
Inagaki, Kei; Ishihara, Kengo; Ishida, Mariko; Watanabe, Ai; Fujiwara, Mika; Komatsu, Yuko; Shirai, Mika; Kato, Yoshiho; Takanezawa, Ami; Furuyashiki, Takashi; Takata, Hiroki; Seyama, Yousuke
2011-01-01
Enzymatically synthesized glycogen (ESG) has high solubility and its solution has low osmotic pressure. Therefore ESG solution could be rapidly absorbed and could be adequate for water rehydration and carbohydrate supplementation during exercise. The object of this study was to evaluate the gastric emptying time and plasma glucose elevation after an administration of ESG solution in comparison with another carbohydrate solution by using a laboratory animal. Male BALB/c mice were administered 10% w/v solution of glucose, maltodextrin, starch, naturally synthesized glycogen (NSG) and ESG at a dose of 20 µL/g body weight for the measurement of gastric emptying rate (Experiment 1) and 10 µL/g body weight for the measurement of plasma glucose elevation (Experiment 2). The osmolarity of gastric content was lower in the ESG and maltodextrin group than the other carbohydrate group. Weight of gastric fluid was significantly lower in the ESG and water group than the glucose group (p<0.01). Plasma glucose level was significantly lower in the ESG group than the glucose group from 0 to 60 min after administration (p<0.01), whereas plasma glucose level was same from 60 to 120 min for the ESG and glucose group (p=0.948). In Experiment 3, BALB/c mice ran on a treadmill for 2 h and were administered 8% of ESG or glucose solution (1.75, 3.5 or 7.0 µL/g body weight) every 20 min during running. There was no difference in post-exercise muscle glycogen level. These data suggest that 1) ESG beverage does not disturb water absorption because of its short gastric emptying time and 2) ESG slowly elevates plasma glucose level and maintains it for a prolonged time compared to the glucose solution.
Montessori Preschool Elevates and Equalizes Child Outcomes: A Longitudinal Study
Lillard, Angeline S.; Heise, Megan J.; Richey, Eve M.; Tong, Xin; Hart, Alyssa; Bray, Paige M.
2017-01-01
Quality preschool programs that develop the whole child through age-appropriate socioemotional and cognitive skill-building hold promise for significantly improving child outcomes. However, preschool programs tend to either be teacher-led and didactic, or else to lack academic content. One preschool model that involves both child-directed, freely chosen activity and academic content is Montessori. Here we report a longitudinal study that took advantage of randomized lottery-based admission to two public Montessori magnet schools in a high-poverty American city. The final sample included 141 children, 70 in Montessori and 71 in other schools, most of whom were tested 4 times over 3 years, from the first semester to the end of preschool (ages 3–6), on a variety of cognitive and socio-emotional measures. Montessori preschool elevated children’s outcomes in several ways. Although not different at the first test point, over time the Montessori children fared better on measures of academic achievement, social understanding, and mastery orientation, and they also reported relatively more liking of scholastic tasks. They also scored higher on executive function when they were 4. In addition to elevating overall performance on these measures, Montessori preschool also equalized outcomes among subgroups that typically have unequal outcomes. First, the difference in academic achievement between lower income Montessori and higher income conventionally schooled children was smaller at each time point, and was not (statistically speaking) significantly different at the end of the study. Second, defying the typical finding that executive function predicts academic achievement, in Montessori classrooms children with lower executive function scored as well on academic achievement as those with higher executive function. This suggests that Montessori preschool has potential to elevate and equalize important outcomes, and a larger study of public Montessori preschools is warranted. PMID:29163248
Coccolithophore community response to increasing pCO2 in Mediterranean oligotrophic waters
NASA Astrophysics Data System (ADS)
Oviedo, A. M.; Ziveri, P.; Gazeau, F.
2017-02-01
The effects of elevated partial pressure of CO2 (pCO2) on plankton communities in oligotrophic ecosystems were studied during two mesocosm experiments: one during summer 2012 in the Bay of Calvi, France, and another during winter 2013 in the Bay of Villefranche, France. Here we report on the relative abundances of coccolithophores versus siliceous phytoplankton, coccolithophore community structure, Emiliania huxleyi coccolith morphology and calcification degree. A pCO2 mediated succession of phytoplankton groups did not occur. During both experiments, coccolithophore abundance and community structure varied with time independently of pCO2 levels. Changes in the community structure were partly explained by the concentration of phosphate during the winter experiment. During the summer experiment, it was not clearly related to any of the parameters measured but possibly to changes in temperature. Phenological changes in the community and an attenuated response due to the low biomass building during the winter experiment could have masked the response to pCO2. E. huxleyi dominated the coccolithophore community in winter; it was not affected by elevated pCO2 at any time. In contrast, the abundance of Rabdosphaera clavigera, the dominant species in summer, increased with time and this increase was affected at elevated pCO2. Thus, a different coccolithophore community response based on species-specific sensitivities to pCO2 is still likely. Finally, elevated pCO2 had no traceable effect on E. huxleyi (type A) coccolith morphology or on the degree of coccolith calcification. Our results highlight the possibility that, in oligotrophic regions, nutrient availability, temperature or intrinsic phenological changes might exert larger constrains on the coccolithophore community structure than high pCO2 does solely.
Correction of laser range tracking data for atmospheric refraction at elevations above 10 degrees
NASA Technical Reports Server (NTRS)
Marini, J. W.; Murray, C. W., Jr.
1973-01-01
A formula for correcting laser measurements of satellite range for the effect of atmospheric refraction is given. The corrections apply above 10 deg elevation to satellites whose heights exceed 70 km. The meteorological measurements required are the temperature, pressure, and relative humidity of the air at the laser site at the time of satellite pass. The accuracy of the formula was tested by comparison with corrections obtained by ray-tracing radiosonde profiles. The standard deviation of the difference between the refractive retardation given by the formula and that calculated by ray-tracing was less than about 0.04% of the retardation or about 0.5 cm at 10 deg elevation, decreasing to 0.04 cm near zenith.
NASA Astrophysics Data System (ADS)
Reynard, Linda M.; Meltzer, David J.; Emslie, Steven D.; Tuross, Noreen
2015-03-01
High elevation plant and animal communities are considered extremely sensitive to environmental change. We investigated an exceptional fossil record of yellow-bellied marmot (Marmota flaviventris) specimens that was recovered from Cement Creek Cave (elev. 2860 m) and ranged in age from radiocarbon background circa 49.8 cal ka BP to ~ 1 cal ka BP. We coupled isotopic and radiocarbon measurements (δ18O, δD, δ15N, δ13C, and 14C) of bone collagen from individually-AMS dated specimens of marmots to assess ecological responses by this species to environmental change over time in a high elevation basin in the Rocky Mountains of southwestern Colorado, USA. We find little change in all four isotope ratios over time, demonstrating considerable environmental stability during periods when the marmots were present. The stable ecology and the apparent persistence of the small mammal community in the cave fauna throughout the late Quaternary are in marked contrast to the changes that occurred in the large mammal community, including local extirpation and extinction, at the end of the Pleistocene.
Björ, Ove; Jonsson, Håkan; Damber, Lena; Burström, Lage; Nilsson, Tohr
2016-01-01
A cohort study that examined iron ore mining found negative associations between cumulative working time employed underground and several outcomes, including mortality of cerebrovascular diseases. In this cohort study, and using the same group of miners, we examined whether work in an outdoor environment could explain elevated cerebrovascular disease rates. This study was based on a Swedish iron ore mining cohort consisting of 13,000 workers. Poisson regression models were used to generate smoothed estimates of standardized mortality ratios and adjusted rate ratios, both models by cumulative exposure time in outdoor work. The adjusted rate ratio between employment classified as outdoor work ≥25 years and outdoor work 0-4 years was 1.62 (95 % CI 1.07-2.42). The subgroup underground work ≥15 years deviated most in occurrence of cerebrovascular disease mortality compared with the external reference population: SMR (0.70 (95 % CI 0.56-0.85)). Employment in outdoor environments was associated with elevated rates of cerebrovascular disease mortality. In contrast, work in tempered underground employment was associated with a protecting effect.
Data from the German Chest Pain Unit Registry: The well known gap between knowledge and practice.
Fernández-Bergés, Daniel
2017-11-01
In-hospital mortality of acute myocardial infarction with ST segment elevation remains high and is influenced by many factors, some of which are modifiable such as time to treatment initiation and modality of treatment. It is well established that reperfusion therapy is the gold-standard in the management of ST-elevation acute myocardial infarction. Despite recent developments and clear, comprehensible guidelines recommendations, it remains difficult to disseminate this knowledge to medical practitioners. The German Chest Pain Unit shows that the best door-to-balloon time is reached when patients contact the Emergency Medical Systems (EMS) directly, rather than when referred by the general practitioner (GP), or are transferred from another hospital, or present as a self-referral. In order to improve mortality in ST-elevation acute myocardial infarction, patients must be able to recognize symptoms and call the EMS as soon as possible, in addition to having an ECG within ten minutes and direct access to reperfusion therapy (PPCI preferred). The German Registry has highlighted the importance of training both patients and doctors. Copyright © 2017 Elsevier B.V. All rights reserved.
Development of a GNSS Buoy for Monitoring Water Surface Elevations in Estuaries and Coastal Areas.
Lin, Yen-Pin; Huang, Ching-Jer; Chen, Sheng-Hsueh; Doong, Dong-Jiing; Kao, Chia Chuen
2017-01-18
In this work, a Global Navigation Satellite System (GNSS) buoy that utilizes a Virtual Base Station (VBS) combined with the Real-Time Kinematic (RTK) positioning technology was developed to monitor water surface elevations in estuaries and coastal areas. The GNSS buoy includes a buoy hull, a RTK GNSS receiver, data-transmission devices, a data logger, and General Purpose Radio Service (GPRS) modems for transmitting data to the desired land locations. Laboratory and field tests were conducted to test the capability of the buoy and verify the accuracy of the monitored water surface elevations. For the field tests, the GNSS buoy was deployed in the waters of Suao (northeastern part of Taiwan). Tide data obtained from the GNSS buoy were consistent with those obtained from the neighboring tide station. Significant wave heights, zero-crossing periods, and peak wave directions obtained from the GNSS buoy were generally consistent with those obtained from an accelerometer-tilt-compass (ATC) sensor. The field tests demonstrate that the developed GNSS buoy can be used to obtain accurate real-time tide and wave data in estuaries and coastal areas.
Pietrini, F; Bianconi, D; Massacci, A; Iannelli, M A
2016-05-15
The objective of this study was to investigate the combined effects of elevated CO2 and cadmium (Cd) treatments on growth, photosynthetic efficiency and phytoremediation ability in Lemna minor L. Plants of L. minor were exposed to different Cd concentrations (0, 1.5, 2.5 and 5 mg L(-1) Cd) for periods of 24, 48 and 72 h at ambient (AC) and at elevated (EC) CO2 (350 and 700 ppm, respectively). Cadmium concentration, bioconcentration factor, enzyme activities and thiols content enhanced in plants with the increase of Cd treatments, time of exposure and at both CO2 levels. Glutathione levels increased only at AC. Growth, photosynthetic and chlorophyll fluorescence parameters, and the reduced glutathione to oxidized glutathione ratio declined in plants with increasing exposure time, Cd treatments and at both CO2 levels. Our results suggested that the alleviation of toxicity, at low Cd doses, observed in L. minor grown at EC is dependent on both increased photosynthesis and an enhanced antioxidant capacity. Copyright © 2016 Elsevier B.V. All rights reserved.
Development of a GNSS Buoy for Monitoring Water Surface Elevations in Estuaries and Coastal Areas
Lin, Yen-Pin; Huang, Ching-Jer; Chen, Sheng-Hsueh; Doong, Dong-Jiing; Kao, Chia Chuen
2017-01-01
In this work, a Global Navigation Satellite System (GNSS) buoy that utilizes a Virtual Base Station (VBS) combined with the Real-Time Kinematic (RTK) positioning technology was developed to monitor water surface elevations in estuaries and coastal areas. The GNSS buoy includes a buoy hull, a RTK GNSS receiver, data-transmission devices, a data logger, and General Purpose Radio Service (GPRS) modems for transmitting data to the desired land locations. Laboratory and field tests were conducted to test the capability of the buoy and verify the accuracy of the monitored water surface elevations. For the field tests, the GNSS buoy was deployed in the waters of Suao (northeastern part of Taiwan). Tide data obtained from the GNSS buoy were consistent with those obtained from the neighboring tide station. Significant wave heights, zero-crossing periods, and peak wave directions obtained from the GNSS buoy were generally consistent with those obtained from an accelerometer-tilt-compass (ATC) sensor. The field tests demonstrate that the developed GNSS buoy can be used to obtain accurate real-time tide and wave data in estuaries and coastal areas. PMID:28106763
Lande, Russell
2009-07-01
Adaptation to a sudden extreme change in environment, beyond the usual range of background environmental fluctuations, is analysed using a quantitative genetic model of phenotypic plasticity. Generations are discrete, with time lag tau between a critical period for environmental influence on individual development and natural selection on adult phenotypes. The optimum phenotype, and genotypic norms of reaction, are linear functions of the environment. Reaction norm elevation and slope (plasticity) vary among genotypes. Initially, in the average background environment, the character is canalized with minimum genetic and phenotypic variance, and no correlation between reaction norm elevation and slope. The optimal plasticity is proportional to the predictability of environmental fluctuations over time lag tau. During the first generation in the new environment the mean fitness suddenly drops and the mean phenotype jumps towards the new optimum phenotype by plasticity. Subsequent adaptation occurs in two phases. Rapid evolution of increased plasticity allows the mean phenotype to closely approach the new optimum. The new phenotype then undergoes slow genetic assimilation, with reduction in plasticity compensated by genetic evolution of reaction norm elevation in the original environment.
NASA Astrophysics Data System (ADS)
Kueppers, L. M.
2010-12-01
Niche models and paleoecological studies indicate that future climate change will alter the geographic distributions of plant species. Changes in temperature, snowmelt timing, or moisture conditions at one edge of a species’ range may have different consequences for recruitment, carbon exchange, phenology, and survival than changes at another edge. Similarly, local genetic adaptation may constrain species and community responses to climate change. We have established a new experiment to investigate potential shifts in the distribution of subalpine tree species, and the alpine species they might replace. We are asking how tree species recruitment and alpine species growth and reproduction vary within their current ranges, and in response to temperature and soil moisture manipulations. We are also examining whether genetic provenance and ecosystem processes constrain tree seedling and alpine herb responses. Our Alpine Treeline Warming Experiment is located across three sites at Niwot Ridge, CO, ranging from near the lower limit of subalpine forest to alpine tundra. We use infrared heaters to raise growing season surface soil temperatures by 4-5°C, and to lengthen the growing season. The warming treatment is crossed with a soil moisture manipulation to distinguish effects due to higher temperatures from those due to drier soil. Each plot is a common garden sown with high and low elevation provenances of limber pine (Pinus flexilis) and Engelmann spruce (Picea engelmannii). We established an additional set of experimental plots to examine treatment effects on alpine species phenology, growth and reproduction. Under ambient conditions in 2009, tree seedling germination rate, lifespan, and first season survival was higher within the species’ current range than in the alpine, and for Engelmann spruce, was higher at the low elevation limit than the high elevation limit. Source population (low vs. high elevation) was a significant factor explaining natural variation in germination rates and timing, seedling physiology, and seedling survival. In 2010, the first season with experimental effects data, the timing of germination was substantially advanced with warming for both species, and warming appeared to increase germination rates for limber pine, but to depress rates for Engelmann spruce at treeline. Seedling carbon balance was negative at the warmest leaf temperatures and there is some indication that the low elevation provenance has a higher total assimilation rate and net carbon gain than the high elevation provenance. Water availability was an important driver of variation in carbon assimilation through the growing season. Our early results suggest that with higher germination rates and lower mortality rates, limber pine is better able to recruit into the alpine than Engelmann spruce, and that lower elevation provenances of limber pine are better at assimilating carbon for growth regardless of site. Ultimate success in seedling establishment may be more contingent on water availability than temperature, even at these high elevations.
Butler, Robert J; Lehr, Michael E; Fink, Michael L; Kiesel, Kyle B; Plisky, Phillip J
2013-09-01
Field expedient screening tools that can identify individuals at an elevated risk for injury are needed to minimize time loss in American football players. Previous research has suggested that poor dynamic balance may be associated with an elevated risk for injury in athletes; however, this has yet to be examined in college football players. To determine if dynamic balance deficits are associated with an elevated risk of injury in collegiate football players. It was hypothesized that football players with lower performance and increased asymmetry in dynamic balance would be at an elevated risk for sustaining a noncontact lower extremity injury. Prospective cohort study. Fifty-nine collegiate American football players volunteered for this study. Demographic information, injury history, and dynamic balance testing performance were collected, and noncontact lower extremity injuries were recorded over the course of the season. Receiver operator characteristic curves were calculated based on performance on the Star Excursion Balance Test (SEBT), including composite score and asymmetry, to determine the population-specific risk cut-off point. Relative risk was then calculated based on these variables, as well as previous injury. A cut-off point of 89.6% composite score on the SEBT optimized the sensitivity (100%) and specificity (71.7%). A college football player who scored below 89.6% was 3.5 times more likely to get injured. Poor performance on the SEBT may be related to an increased risk for sustaining a noncontact lower extremity injury over the course of a competitive American football season. College football players should be screened preseason using the SEBT to identify those at an elevated risk for injury based upon dynamic balance performance to implement injury mitigation strategies to this specific subgroup of athletes.
Effect of particle size on calcium release and elevation of pH of endodontic cements.
Saghiri, Mohammad Ali; Asatourian, Armen; Orangi, Jafar; Lotfi, Mehrdad; Soukup, Jason W; Garcia-Godoy, Franklin; Sheibani, Nader
2015-06-01
Elevation of pH and calcium ion release are of great importance in antibacterial activity and the promotion of dental soft and hard tissue healing process. In this study, we evaluated the effect of particle size on the elevation of pH and the calcium ion release from calcium silicate-based dental cements. Twelve plastic tubes were divided into three groups, filled with white mineral trioxide aggregate (WMTA), WMTA plus 1% methylcellulose, and nano-modified WMTA (nano-WMTA), and placed inside flasks containing 10 ml of distilled water. The pH values were measured using a pH sensor 3, 24, 72, and 168 h after setting of the cements. The calcium ion release was measured using an atomic absorption spectrophotometer with same sample preparation method. Data were subjected to two-way analysis of variance (anova) followed by post hoc Tukey tests with significance level of P < 0.05. Nano-WMTA showed significant pH elevation only after 24 h (P < 0.05) compared with WMTA, and after 3, 24, and 72 h compared with WMTA plus 1% methylcellulose (P < 0.05). Nano-WMTA showed significantly higher calcium ion release values compared to the other two groups (P < 0.05). Nano-modification of WMTA remarkably increased the calcium ion release at all time intervals postsetting, which can significantly influence the osteogenic properties of human dental pulp cells and as a consequence enhance mineralized matrix nodule formation to achieve desirable clinical outcomes. However, the increase in pH values mainly occurred during the short time postsetting. Addition of 1% methylcellulose imposed a delay in elevation of pH and calcium ion release by WMTA. © 2015 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.
Dalbøge, Annett; Hansson, Gert-Åke; Frost, Poul; Andersen, Johan Hviid; Heilskov-Hansen, Thomas; Svendsen, Susanne Wulff
2016-08-01
We recently constructed a general population job exposure matrix (JEM), The Shoulder JEM, based on expert ratings. The overall aim of this study was to convert expert-rated job exposures for upper arm elevation and repetitive shoulder movements to measurement scales. The Shoulder JEM covers all Danish occupational titles, divided into 172 job groups. For 36 of these job groups, we obtained technical measurements (inclinometry) of upper arm elevation and repetitive shoulder movements. To validate the expert-rated job exposures against the measured job exposures, we used Spearman rank correlations and the explained variance[Formula: see text] according to linear regression analyses (36 job groups). We used the linear regression equations to convert the expert-rated job exposures for all 172 job groups into predicted measured job exposures. Bland-Altman analyses were used to assess the agreement between the predicted and measured job exposures. The Spearman rank correlations were 0.63 for upper arm elevation and 0.64 for repetitive shoulder movements. The expert-rated job exposures explained 64% and 41% of the variance of the measured job exposures, respectively. The corresponding calibration equations were y=0.5%time+0.16×expert rating and y=27°/s+0.47×expert rating. The mean differences between predicted and measured job exposures were zero due to calibration; the 95% limits of agreement were ±2.9% time for upper arm elevation >90° and ±33°/s for repetitive shoulder movements. The updated Shoulder JEM can be used to present exposure-response relationships on measurement scales. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/
Henry, Jason T; Christiansen, Ellen; Garberich, Ross F; Handran, Chauncy B; Larson, David M; Unger, Barbara T; Henry, Timothy D
2014-03-01
Transfer for primary percutaneous coronary intervention (PCI) is superior to fibrinolysis if performed in a timely manner but frequently requires dislocation of patients and their families from their local community. Although patient satisfaction is increasingly viewed as an important quality indicator, there are no data on how emergent transfer for PCI affects patients with ST-segment-elevation myocardial infarction and their families. The Minneapolis Heart Institute's Level 1 Regional ST-Segment-Elevation Myocardial Infarction program is designed to facilitate emergent transfer for PCI in patients with ST-segment-elevation myocardial infarction from 31 rural and community hospitals. To determine the effect of emergent transfer, questionnaires were given to 152 patients and their families who survived to hospital discharge with a 65.8% response rate (mean age, 63.9 years; 29% women). Ninety-five percent of patients felt the reasons and process of transfer were well explained, and 97% felt transfer for care was necessary. Despite this, 15% of patients would have preferred to stay in their local hospital. The majority of the families felt the transfer process (88%) and family member's condition (94%) were well explained. Although 99% felt it was necessary for their family member to be transferred for specialized care, 11% of families still would have preferred that their family members remain at the local community hospital. Our results suggest that ST-segment-elevation myocardial infarction patients and families can be informed, even in time-critical situations, about the transfer process for PCI and understand the need for specialized care. Still, a significant minority would prefer to stay at their local hospital, despite acknowledging transfer for PCI provided optimal care.
Hurricane Rita surge data, southwestern Louisiana and southeastern Texas, September to November 2005
McGee, Benton D.; Goree, Burl B.; Tollett, Roland W.; Woodward, Brenda K.; Kress, Wade H.
2006-01-01
Pressure transducers and high-water marks were used to document the inland water levels related to storm surge generated by Hurricane Rita in southwestern Louisiana and southeastern Texas. On September 22-23, 2005, an experimental monitoring network consisting of 47 pressure transducers (sensors) was deployed at 33 sites over an area of about 4,000 square miles to record the timing, extent, and magnitude of inland hurricane storm surge and coastal flooding. Sensors were programmed to record date and time, temperature, and barometric or water pressure. Water pressure was corrected for changes in barometric pressure and salinity. Elevation surveys using global-positioning systems and differential levels were used to relate all storm-surge water-level data, reference marks, benchmarks, sensor measuring points, and high-water marks to the North American Vertical Datum of 1988 (NAVD 88). The resulting data indicated that storm-surge water levels over 14 feet above NAVD 88 occurred at three locations and rates of water-level rise greater than 5 feet per hour occurred at three locations near the Louisiana coast. Quality-assurance measures were used to assess the variability and accuracy of the water-level data recorded by the sensors. Water-level data from sensors were similar to data from co-located sensors, permanent U.S. Geological Survey streamgages, and water-surface elevations performed by field staff. Water-level data from sensors at selected locations were compared to corresponding high-water mark elevations. In general, the water-level data from sensors were similar to elevations of high quality high-water marks, while reporting consistently higher than elevations of lesser quality high-water marks.
Monitoring Reservoir Storage in South Asia from Satellite Remote Sensing
NASA Astrophysics Data System (ADS)
Zhang, S.; Gao, H.; Naz, B.
2013-12-01
Realtime reservoir storage information is essential for accurate flood monitoring and prediction in South Asia, where the fatality rate (by area) due to floods is among the highest in the world. However, South Asia is dominated by international river basins where communications among neighboring countries about reservoir storage and management are extremely limited. In this study, we use a suite of NASA satellite observations to achieve high quality estimation of reservoir storage and storage variations at near realtime in South Asia. The monitoring approach employs vegetation indices from the Moderate Resolution Imaging Spectroradiometer (MODIS) 16-day 250 m MOD13Q1 product and the surface elevation data from the Geoscience Laser Altimeter System (GLAS) on board the Ice, Cloud and land Elevation Satellite (ICESat). This approach contains four steps: 1) identifying the reservoirs with ICESat GLAS overpasses and extracting the elevation data for these locations; 2) using the K-means method for water classification from MODIS andapplying a novel post-classification algorithm to enhance water area estimation accuracy; 3) deriving the relationship between the MODIS water surface area and the ICESat elevation; and 4) estimating the storage of reservoirs over time based on the elevation-area relationship and the MODIS water area time series. For evaluation purposes, we compared the satellite-based reservoir storage with gauge observations for 16 reservoirs in South Asia. The storage estimates were highly correlated with observations (R = 0.92 to 0.98), with values for the normalized root mean square error (NRMSE) ranging from 8.7% to 25.2%. Using this approach, storage and storage variations were estimated for 16 South Asia reservoirs from 2000 to 2012.
Chen, Xi; Sun, Weiwen; Pan, Ying; Yang, Quan; Cao, Kaiyi; Zhang, Jin; Zhang, Yizhi; Chen, Mincong; Chen, Feidi; Huang, Yueling; Dai, Lijun; Chen, Shengqiang
2013-10-01
To investigate whether lithium modifies open-field and elevated plus maze behavior, and brain phospho-glycogen synthase kinase 3 (P-GSK3beta) expression in Fmr1 knockout mice. One hundred and eighty FVB mice, including knockout and wild type, with an age of 30 days were used. An open-field and elevated plus maze was utilized to test behavior, while western blot was used to measure the P-GSK3beta expression. Six groups were formed: control (saline), lithium chloride 30, 60, 90, 120, and 200 mg/kg. The experiments were carried out in the Institute of Neuroscience, Second Affiliated Hospital of Guangzhou Medical University, Guangzhou, China between January and June 2012. Lithium significantly decreased total distance, crossing, central area time, and center entry in the open-field test (p<0.05), and significantly reduced open-arm tracking, open-arm entry, and open-arm time in the elevated plus maze (p<0.05) in knockout mice. In wild type mice, significant changes were observed in both behavior tests in some treatment groups. Lithium ameliorated P-GSK3beta expression in the hippocampus of all the treatment groups in knockout mice (p<0.05). However, lithium did not modify either GSK3beta expression in tissues of knockout mice, or P-GSK3beta or GSK3beta expression in tissues of wild type mice. Lithium ameliorated open-field and elevated plus maze behaviors of Fmr1 knockout mice. This effect may be related to its enhancement of P-GSK3beta expression. Our findings suggest that lithium might have a therapeutic effect in fragile X syndrome.
Kobayashi, Minoru; Nukui, Akinori; Kamai, Takao
2017-02-01
It is common to repeat prostate-specific antigen (PSA) measurements for men with intermediate PSA elevation before prostate biopsy. In this scenario, men with persistently elevated PSA values may have considerable psychological distress. We attempted to determine whether elevated PSA values have psychological effects on these men in association with the timing of measurement, PSA kinetics, and biopsy results. In order to investigate the initial and late effects of PSA tests on psychological distress during serial measurements, two groups of men with screen-positive results (PSA ≥3 ng/ml) were studied-205 men whose first questionnaires regarding anxiety and depression were taken at initial screening (group A), and 103 men whose questionnaires were taken at repeated measurement for prior PSA elevation (group B). The level of distress was generally low. There were no significant differences in distress between the two groups, suggesting a constant psychological effect by elevated PSA values over a long period of time. The distress of men in group A increased significantly as PSA levels rose and decreased when they fell to normal range. On the other hand, the distress of men in group B did not change regardless of PSA kinetics, indicating that their psychological condition seemed susceptible to subtle PSA change only in the initial phase of measurements. Unexpectedly, men with benign results showed insignificant but higher distress after prostate biopsy. Although a small fraction of men have psychological distress caused by changes in PSA levels, the benefits, risks (psychological and physical), and limitations of PSA tests must be adequately explained to the patients before entering the screening program.
Konishi, Tsuyoshi; Shimada, Yoshifumi; Hsu, Meier; Tufts, Lauren; Jimenez-Rodriguez, Rosa; Cercek, Andrea; Yaeger, Rona; Saltz, Leonard; Smith, J Joshua; Nash, Garrett M; Guillem, José G; Paty, Philip B; Garcia-Aguilar, Julio; Gonen, Mithat; Weiser, Martin R
2018-03-01
Guidelines recommend measuring preoperative carcinoembryonic antigen (CEA) in patients with colon cancer. Although persistently elevated CEA after surgery has been associated with increased risk for metastatic disease, prognostic significance of elevated preoperative CEA that normalized after resection is unknown. To investigate whether patients with elevated preoperative CEA that normalizes after colon cancer resection have a higher risk of recurrence than patients with normal preoperative CEA. This retrospective cohort analysis was conducted at a comprehensive cancer center. Consecutive patients with colon cancer who underwent curative resection for stage I to III colon adenocarcinoma at the center from January 2007 to December 2014 were identified. Patients were grouped into 3 cohorts: normal preoperative CEA, elevated preoperative but normalized postoperative CEA, and elevated preoperative and postoperative CEA. Three-year recurrence-free survival (RFS) and hazard function curves over time were analyzed. A total of 1027 patients (461 [50.4%] male; median [IQR] age, 64 [53-75] years) were identified. Patients with normal preoperative CEA had 7.4% higher 3-year RFS (n = 715 [89.7%]) than the combined cohorts with elevated preoperative CEA (n = 312 [82.3%]) (P = .01) but had RFS similar to that of patients with normalized postoperative CEA (n = 142 [87.9%]) (P = .86). Patients with elevated postoperative CEA had 14.9% lower RFS (n = 57 [74.5%]) than the combined cohorts with normal postoperative CEA (n = 857 [89.4%]) (P = .001). The hazard function of recurrence for elevated postoperative CEA peaked earlier than for the other cohorts. Multivariate analyses confirmed that elevated postoperative CEA (hazard ratio [HR], 2.0; 95% CI, 1.1-3.5), but not normalized postoperative CEA (HR, 0.77; 95% CI, 0.45-1.30), was independently associated with shorter RFS. Elevated preoperative CEA that normalizes after resection is not an indicator of poor prognosis. Routine measurement of postoperative, rather than preoperative, CEA is warranted. Patients with elevated postoperative CEA are at increased risk for recurrence, especially within the first 12 months after surgery.
Proprioceptive input patterns elevator activity in the locust flight system.
Wolf, H; Pearson, K G
1988-06-01
1. In the locust, Locusta migratoria, the roles of two groups of wing sense organs, hind wing tegulae and wing-hinge stretch receptors, in the generation of the flight motor pattern were investigated. A preparation was employed that allowed the intracellular recording of neural activity in almost intact tethered flying locusts or after selective manipulations of sensory input. The functions of the two sets of receptors were assessed 1) by studying the phases of their discharges in the wingbeat cycle (Fig. 3), 2) by the selective ablation of input from the receptors (Figs. 4-7), and 3) by the selective stimulation of the receptor afferents (Figs. 8-12). 2. Input from the tegulae was found to be responsible for the initiation of elevator activity (Figs. 9 and 10) and for the generation of a distinct initial rapid depolarization (Figs. 4, 5, and 8) characteristic of elevator motor neuron activity in intact locusts (Figs. 1 and 16). 3. Input from the wing-hinge stretch receptors was found to control the duration of elevator depolarizations by the graded suppression of a second late component of the elevator depolarizations as wingbeat frequency increased (Figs. 6, 7, 11, and 12). The characteristics of this late component of elevator activity suggested that it is generated by the same (central nervous) mechanism that produces the elevator depolarizations recorded in deafferented animals (Fig. 2). Apparently this late component contributes to the intact pattern of elevator depolarizations only at lower wingbeat frequencies and is abolished by the action of stretch-receptor input at frequencies above approximately 15 Hz (Figs. 1, 2, and 4). At these high wingbeat frequencies elevator activity is dominated by the rapid depolarizations generated as a result of tegula input. 4. The present study demonstrates 1) that the timing of elevator motor neuron activity is determined by phasic afferent input from tegulae and stretch receptors and 2) that input from the stretch receptors controls the duration of elevator activity in the wingbeat cycle following the wing movement that was responsible for the generation of the receptor discharge.
1976-01-28
source-receiver geometry dynamics. For a given time instant, each of the subroutines outputs time variables ( emission time, arrival time...transmission loss, depression/elevation and azimuthal arrival angles, received frequency and range variables (range at emission time, range at arrival time...with the wind equal 24.5 kts. In the double bottom bounce regions, the emission angles (at the virtual surface source) are moderately small (15
Lunar transportation scenarios utilising the Space Elevator.
Engel, Kilian A
2005-01-01
The Space Elevator (SE) concept has begun to receive an increasing amount of attention within the space community over the past couple of years and is no longer widely dismissed as pure science fiction. In light of the renewed interest in a, possibly sustained, human presence on the Moon and the fact that transportation and logistics form the bottleneck of many conceivable lunar missions, it is interesting to investigate what role the SE could eventually play in implementing an efficient Earth to Moon transportation system. The elevator allows vehicles to ascend from Earth and be injected into a trans-lunar trajectory without the use of chemical thrusters, thus eliminating gravity loss, aerodynamic loss and the need of high thrust multistage launch systems. Such a system therefore promises substantial savings of propellant and structural mass and could greatly increase the efficiency of Earth to Moon transportation. This paper analyzes different elevator-based trans-lunar transportation scenarios and characterizes them in terms of a number of benchmark figures. The transportation scenarios include direct elevator-launched trans-lunar trajectories, elevator launched trajectories via L1 and L2, as well as launch from an Earth-based elevator and subsequent rendezvous with lunar elevators placed either on the near or on the far side of the Moon. The benchmark figures by which the different transfer options are characterized and evaluated include release radius (RR), required delta v, transfer times as well as other factors such as accessibility of different lunar latitudes, frequency of launch opportunities and mission complexity. The performances of the different lunar transfer options are compared with each other as well as with the performance of conventional mission concepts, represented by Apollo. c2005 Elsevier Ltd. All rights reserved.
Wathen, Steve; Thorne, James H.; Holguin, Andrew; Schwartz, Mark W.
2014-01-01
Evidence for significant losses of species richness or biodiversity, even within protected natural areas, is mounting. Managers are increasingly being asked to monitor biodiversity, yet estimating biodiversity is often prohibitively expensive. As a cost-effective option, we estimated the spatial and temporal distribution of species richness for four taxonomic groups (birds, mammals, herpetofauna (reptiles and amphibians), and plants) within Sequoia and Kings Canyon National Parks using only existing biological studies undertaken within the Parks and the Parks' long-term wildlife observation database. We used a rarefaction approach to model species richness for the four taxonomic groups and analyzed those groups by habitat type, elevation zone, and time period. We then mapped the spatial distributions of species richness values for the four taxonomic groups, as well as total species richness, for the Parks. We also estimated changes in species richness for birds, mammals, and herpetofauna since 1980. The modeled patterns of species richness either peaked at mid elevations (mammals, plants, and total species richness) or declined consistently with increasing elevation (herpetofauna and birds). Plants reached maximum species richness values at much higher elevations than did vertebrate taxa, and non-flying mammals reached maximum species richness values at higher elevations than did birds. Alpine plant communities, including sagebrush, had higher species richness values than did subalpine plant communities located below them in elevation. These results are supported by other papers published in the scientific literature. Perhaps reflecting climate change: birds and herpetofauna displayed declines in species richness since 1980 at low and middle elevations and mammals displayed declines in species richness since 1980 at all elevations. PMID:25469873
Elevated CO2 and temperature increase soil C losses from a soybean-maize ecosystem.
Black, Christopher K; Davis, Sarah C; Hudiburg, Tara W; Bernacchi, Carl J; DeLucia, Evan H
2017-01-01
Warming temperatures and increasing CO 2 are likely to have large effects on the amount of carbon stored in soil, but predictions of these effects are poorly constrained. We elevated temperature (canopy: +2.8 °C; soil growing season: +1.8 °C; soil fallow: +2.3 °C) for 3 years within the 9th-11th years of an elevated CO 2 (+200 ppm) experiment on a maize-soybean agroecosystem, measured respiration by roots and soil microbes, and then used a process-based ecosystem model (DayCent) to simulate the decadal effects of warming and CO 2 enrichment on soil C. Both heating and elevated CO 2 increased respiration from soil microbes by ~20%, but heating reduced respiration from roots and rhizosphere by ~25%. The effects were additive, with no heat × CO 2 interactions. Particulate organic matter and total soil C declined over time in all treatments and were lower in elevated CO 2 plots than in ambient plots, but did not differ between heat treatments. We speculate that these declines indicate a priming effect, with increased C inputs under elevated CO 2 fueling a loss of old soil carbon. Model simulations of heated plots agreed with our observations and predicted loss of ~15% of soil organic C after 100 years of heating, but simulations of elevated CO 2 failed to predict the observed C losses and instead predicted a ~4% gain in soil organic C under any heating conditions. Despite model uncertainty, our empirical results suggest that combined, elevated CO 2 and temperature will lead to long-term declines in the amount of carbon stored in agricultural soils. © 2016 John Wiley & Sons Ltd.
Wathen, Steve; Thorne, James H; Holguin, Andrew; Schwartz, Mark W
2014-01-01
Evidence for significant losses of species richness or biodiversity, even within protected natural areas, is mounting. Managers are increasingly being asked to monitor biodiversity, yet estimating biodiversity is often prohibitively expensive. As a cost-effective option, we estimated the spatial and temporal distribution of species richness for four taxonomic groups (birds, mammals, herpetofauna (reptiles and amphibians), and plants) within Sequoia and Kings Canyon National Parks using only existing biological studies undertaken within the Parks and the Parks' long-term wildlife observation database. We used a rarefaction approach to model species richness for the four taxonomic groups and analyzed those groups by habitat type, elevation zone, and time period. We then mapped the spatial distributions of species richness values for the four taxonomic groups, as well as total species richness, for the Parks. We also estimated changes in species richness for birds, mammals, and herpetofauna since 1980. The modeled patterns of species richness either peaked at mid elevations (mammals, plants, and total species richness) or declined consistently with increasing elevation (herpetofauna and birds). Plants reached maximum species richness values at much higher elevations than did vertebrate taxa, and non-flying mammals reached maximum species richness values at higher elevations than did birds. Alpine plant communities, including sagebrush, had higher species richness values than did subalpine plant communities located below them in elevation. These results are supported by other papers published in the scientific literature. Perhaps reflecting climate change: birds and herpetofauna displayed declines in species richness since 1980 at low and middle elevations and mammals displayed declines in species richness since 1980 at all elevations.
Quantifying soil carbon loss and uncertainty from a peatland wildfire using multi-temporal LiDAR
Reddy, Ashwan D.; Hawbaker, Todd J.; Wurster, F.; Zhu, Zhiliang; Ward, S.; Newcomb, Doug; Murray, R.
2015-01-01
Peatlands are a major reservoir of global soil carbon, yet account for just 3% of global land cover. Human impacts like draining can hinder the ability of peatlands to sequester carbon and expose their soils to fire under dry conditions. Estimating soil carbon loss from peat fires can be challenging due to uncertainty about pre-fire surface elevations. This study uses multi-temporal LiDAR to obtain pre- and post-fire elevations and estimate soil carbon loss caused by the 2011 Lateral West fire in the Great Dismal Swamp National Wildlife Refuge, VA, USA. We also determine how LiDAR elevation error affects uncertainty in our carbon loss estimate by randomly perturbing the LiDAR point elevations and recalculating elevation change and carbon loss, iterating this process 1000 times. We calculated a total loss using LiDAR of 1.10 Tg C across the 25 km2 burned area. The fire burned an average of 47 cm deep, equivalent to 44 kg C/m2, a value larger than the 1997 Indonesian peat fires (29 kg C/m2). Carbon loss via the First-Order Fire Effects Model (FOFEM) was estimated to be 0.06 Tg C. Propagating the LiDAR elevation error to the carbon loss estimates, we calculated a standard deviation of 0.00009 Tg C, equivalent to 0.008% of total carbon loss. We conclude that LiDAR elevation error is not a significant contributor to uncertainty in soil carbon loss under severe fire conditions with substantial peat consumption. However, uncertainties may be more substantial when soil elevation loss is of a similar or smaller magnitude than the reported LiDAR error.
Kraemer, Benjamin M; Chandra, Sudeep; Dell, Anthony I; Dix, Margaret; Kuusisto, Esko; Livingstone, David M; Schladow, S Geoffrey; Silow, Eugene; Sitoki, Lewis M; Tamatamah, Rashid; McIntyre, Peter B
2017-05-01
Climate warming is expected to have large effects on ecosystems in part due to the temperature dependence of metabolism. The responses of metabolic rates to climate warming may be greatest in the tropics and at low elevations because mean temperatures are warmer there and metabolic rates respond exponentially to temperature (with exponents >1). However, if warming rates are sufficiently fast in higher latitude/elevation lakes, metabolic rate responses to warming may still be greater there even though metabolic rates respond exponentially to temperature. Thus, a wide range of global patterns in the magnitude of metabolic rate responses to warming could emerge depending on global patterns of temperature and warming rates. Here we use the Boltzmann-Arrhenius equation, published estimates of activation energy, and time series of temperature from 271 lakes to estimate long-term (1970-2010) changes in 64 metabolic processes in lakes. The estimated responses of metabolic processes to warming were usually greatest in tropical/low-elevation lakes even though surface temperatures in higher latitude/elevation lakes are warming faster. However, when the thermal sensitivity of a metabolic process is especially weak, higher latitude/elevation lakes had larger responses to warming in parallel with warming rates. Our results show that the sensitivity of a given response to temperature (as described by its activation energy) provides a simple heuristic for predicting whether tropical/low-elevation lakes will have larger or smaller metabolic responses to warming than higher latitude/elevation lakes. Overall, we conclude that the direct metabolic consequences of lake warming are likely to be felt most strongly at low latitudes and low elevations where metabolism-linked ecosystem services may be most affected. © 2016 John Wiley & Sons Ltd.
Thomas, Patrick K; Dunn, Gary P; Passero, Maxine; Feris, Kevin P
2017-11-01
Cost-effective methods for protecting crops from grazing organisms like rotifers are needed to reduce the risk of pond crashes in mass algal cultures. We present a novel strategy to optimize the exposure time to free ammonia, via control of media pH, in both defined media and dairy anaerobic digester effluent to suppress rotifers and maintain algal productivity. We tested five different free ammonia exposure times (0, 1, 2, 6, and 12h) and found a significant nonlinear effect of exposure time (p<0.0001) but not pH (p>0.9) on rotifer survival. In both media types, 6-12h of elevated free ammonia significantly reduced Brachionus plicatilis rotifer survival with no negative effects on Nannochloropsis oculata, while shorter exposure times were insufficient to inhibit rotifers, leading to severe algal culture crashes. These results suggest that algal crops can be protected from rotifers, without productivity loss, by elevating free ammonia for 6 or more hours. Copyright © 2017 Elsevier Ltd. All rights reserved.
NASA Astrophysics Data System (ADS)
Nilsson, J.; Paolo, F. S.; Simonsen, S.; Gardner, A. S.
2017-12-01
Satellite and airborne altimetry provide the longest continuous record from which the mass balance of the Antarctic ice sheet can be derived, starting with the launch of ERS-1 in 1992. Accurate knowledge of the long-term mass balance is vital for understanding the geophysical processes governing the ice sheet contribution to present day sea-level rise. However, this record is comprised of several different measurement systems, with different accuracies and varying resolution. This poses a major challenge on the interpretation and reconstruction of consistent elevation-change time series for determining long-term ice sheet trends and variability. Previous studies using data from multiple satellite altimetry missions have relied on a cross-calibration technique based on crossover bias analysis to merge records from different sensors. This methodology, though accurate, limits the spatial coverage to typical resolutions of 10-50 km, restricting the approach to regional or continental-wide studies. In this study, we present a novel framework for seamless integration of heterogeneous altimetry records, using an adaptive least-squares minimization technique. The procedure allows reconstructing time series at fine spatial (<5 km) and temporal (monthly) scales, while accounting for sensor-dependent biases and heterogeneous data quality. We synthesize altimetry records spanning the time period 1992-2016 to derive long-term time series of elevation change for the Antarctica ice sheet, including both data from the European Space Agency (ERS-1, ERS-2, Envisat and CryoSat-2) and NASA (ICESat and Operation IceBridge), with future inclusion of data from NASA's ICESat-2. Mission specific errors, estimated from independent airborne measurements and crossover analysis, are propagated to derive uncertainty bounds for each individual time series. We also perform an extensive analysis of the major corrections applied to raw satellite altimetry data to assess their overall effect on the estimated uncertainty. This methodology will allow us to determine robust long-term changes in the surface elevation of grounded Antarctic ice. Such a dataset will be invaluable to advancing ice sheet assimilation efforts and to disentangle causal mechanisms of modern ice sheet response to environmental forcing.
Assessing the benefit of snow data assimilation for runoff modeling in Alpine catchments
NASA Astrophysics Data System (ADS)
Griessinger, Nena; Seibert, Jan; Magnusson, Jan; Jonas, Tobias
2016-09-01
In Alpine catchments, snowmelt is often a major contribution to runoff. Therefore, modeling snow processes is important when concerned with flood or drought forecasting, reservoir operation and inland waterway management. In this study, we address the question of how sensitive hydrological models are to the representation of snow cover dynamics and whether the performance of a hydrological model can be enhanced by integrating data from a dedicated external snow monitoring system. As a framework for our tests we have used the hydrological model HBV (Hydrologiska Byråns Vattenbalansavdelning) in the version HBV-light, which has been applied in many hydrological studies and is also in use for operational purposes. While HBV originally follows a temperature-index approach with time-invariant calibrated degree-day factors to represent snowmelt, in this study the HBV model was modified to use snowmelt time series from an external and spatially distributed snow model as model input. The external snow model integrates three-dimensional sequential assimilation of snow monitoring data with a snowmelt model, which is also based on the temperature-index approach but uses a time-variant degree-day factor. The following three variations of this external snow model were applied: (a) the full model with assimilation of observational snow data from a dense monitoring network, (b) the same snow model but with data assimilation switched off and (c) a downgraded version of the same snow model representing snowmelt with a time-invariant degree-day factor. Model runs were conducted for 20 catchments at different elevations within Switzerland for 15 years. Our results show that at low and mid-elevations the performance of the runoff simulations did not vary considerably with the snow model version chosen. At higher elevations, however, best performance in terms of simulated runoff was obtained when using the snowmelt time series from the snow model, which utilized data assimilation. This was especially true for snow-rich years. These findings suggest that with increasing elevation and the correspondingly increased contribution of snowmelt to runoff, the accurate estimation of snow water equivalent (SWE) and snowmelt rates has gained importance.
Accurate elevation and normal moveout corrections of seismic reflection data on rugged topography
Liu, J.; Xia, J.; Chen, C.; Zhang, G.
2005-01-01
The application of the seismic reflection method is often limited in areas of complex terrain. The problem is the incorrect correction of time shifts caused by topography. To apply normal moveout (NMO) correction to reflection data correctly, static corrections are necessary to be applied in advance for the compensation of the time distortions of topography and the time delays from near-surface weathered layers. For environment and engineering investigation, weathered layers are our targets, so that the static correction mainly serves the adjustment of time shifts due to an undulating surface. In practice, seismic reflected raypaths are assumed to be almost vertical through the near-surface layers because they have much lower velocities than layers below. This assumption is acceptable in most cases since it results in little residual error for small elevation changes and small offsets in reflection events. Although static algorithms based on choosing a floating datum related to common midpoint gathers or residual surface-consistent functions are available and effective, errors caused by the assumption of vertical raypaths often generate pseudo-indications of structures. This paper presents the comparison of applying corrections based on the vertical raypaths and bias (non-vertical) raypaths. It also provides an approach of combining elevation and NMO corrections. The advantages of the approach are demonstrated by synthetic and real-world examples of multi-coverage seismic reflection surveys on rough topography. ?? The Royal Society of New Zealand 2005.
Federal Register 2010, 2011, 2012, 2013, 2014
2010-04-28
... species should tend to prolong elevated catch levels in a multispecies time series, so an observed decline... species was more common in early time series of species compositions and that catch rates and relative abundances of each species have declined. The same commenter noted that early time series data may be...
Moon view period tabulations (with station masking) for Manned Space Flight Network stations, book 1
NASA Technical Reports Server (NTRS)
Gattie, M. M.; Williams, R. L.
1970-01-01
The times during which MSFN stations can view the moon are tabulated. Station view periods for each month are given. All times and dates refer to Greenwich Mean Time. AOS and LOS refer to the center of the moon at zero degrees elevation for moon rise and set, respectively.
Initial Everglades Depth Estimation Network (EDEN) Digital Elevation Model Research and Development
Jones, John W.; Price, Susan D.
2007-01-01
Introduction The Everglades Depth Estimation Network (EDEN) offers a consistent and documented dataset that can be used to guide large-scale field operations, to integrate hydrologic and ecological responses, and to support biological and ecological assessments that measure ecosystem responses to the Comprehensive Everglades Restoration Plan (Telis, 2006). To produce historic and near-real time maps of water depths, the EDEN requires a system-wide digital elevation model (DEM) of the ground surface. Accurate Everglades wetland ground surface elevation data were non-existent before the U.S. Geological Survey (USGS) undertook the collection of highly accurate surface elevations at the regional scale. These form the foundation for EDEN DEM development. This development process is iterative as additional high accuracy elevation data (HAED) are collected, water surfacing algorithms improve, and additional ground-based ancillary data become available. Models are tested using withheld HAED and independently measured water depth data, and by using DEM data in EDEN adaptive management applications. Here the collection of HAED is briefly described before the approach to DEM development and the current EDEN DEM are detailed. Finally future research directions for continued model development, testing, and refinement are provided.
Inflammatory cells in rat skeletal muscle are elevated after electrically stimulated contractions.
McLoughlin, Thomas J; Mylona, Eleni; Hornberger, Troy A; Esser, Karyn A; Pizza, Francis X
2003-03-01
We determined the effect of muscle contractions resulting from high-frequency electrical stimulation (HFES) on inflammatory cells in rat tibialis anterior (TA), plantaris (Pln), and soleus (Sol) muscles at 6, 24, and 72 h post-HFES. A minimum of four and a maximum of seven rats were analyzed at each time point. HFES, applied to the sciatic nerve, caused the Sol and Pln to contract concentrically and the TA to contract eccentrically. Neutrophils were higher (P < 0.05) at 6 and 24 h after HFES in the Sol, Pln, and TA muscles relative to control muscles. ED1(+) macrophages in the Pln were elevated at 6 and 24 h after HFES and were also elevated in the Sol and TA after HFES relative to controls. ED2(+) macrophages in the Sol and TA were elevated at 24 and 72 h after HFES, respectively, and were also elevated in the Pln after HFES relative to controls. In contrast to the TA muscles, the Pln and Sol muscles showed no gross histological abnormalities. Collectively, these data indicate that both eccentric and concentric contractions can increase inflammatory cells in muscle, regardless of whether overt histological signs of injury are apparent.
Stoetzer, Marcus; Felgenträger, Dörthe; Kampmann, Andreas; Schumann, Paul; Rücker, Martin; Gellrich, Nils-Claudius; von See, Constantin
2014-07-01
Subperiosteal preparation using a periosteal elevator leads to disturbances of local periosteal microcirculation. Soft-tissue damage can usually be considerably reduced using piezoelectric technology. For this reason, we investigated the effects of a novel piezoelectric device on local periosteal microcirculation and compared this approach with the conventional preparation of the periosteum using a periosteal elevator. A total of 20 Lewis rats were randomly assigned to one of two groups. Subperiosteal preparation was performed using either a piezoelectric device or a periosteal elevator. Intravital microscopy was performed immediately after the procedure as well as three and eight days postoperatively. Statistical analysis of microcirculatory parameters was performed offline using analysis of variance (ANOVA) on ranks (p<0.05). At all time points investigated, intravital microscopy demonstrated significantly higher levels of periosteal perfusion in the group of rats that underwent piezosurgery than in the group of rats that underwent treatment with a periosteal elevator. The use of a piezoelectric device for subperiosteal preparation is associated with better periosteal microcirculation than the use of a conventional periosteal elevator. As a result, piezoelectric devices can be expected to have a positive effect on bone metabolism. Copyright © 2014 Elsevier Inc. All rights reserved.
Cheung, Victoria; Segal, Devorah; Gardner, Sharon L; Zagzag, David; Wisoff, Jeffrey H; Allen, Jeffrey C; Karajannis, Matthias A
2016-09-01
Patients with marker-positive central nervous system (CNS) germ cell tumors are typically monitored for tumor recurrence with both tumor markers (AFP and b-hCG) and MRI. We hypothesize that the recurrence of these tumors will always be accompanied by an elevation in tumor markers, and that surveillance MRI may not be necessary. We retrospectively identified 28 patients with CNS germ cell tumors treated at our institution that presented with an elevated serum or cerebrospinal fluid (CSF) tumor marker at the time of diagnosis. We then identified those who had a tumor recurrence after having been in remission and whether each recurrence was detected via MRI changes, elevated tumor markers, or both. Four patients suffered a tumor recurrence. Only one patient had simultaneously elevated tumor markers and MRI evidence of recurrence. Two patients had evidence of recurrence on MRI without corresponding elevations in serum or CSF tumor markers. One patient had abnormal tumor markers with no evidence of recurrence on MRI until 6 months later. We conclude that in patients with marker-positive CNS germ cell tumors who achieve complete remission, continued surveillance imaging in addition to measurement of tumor markers is indicated to detect recurrences.
Slitrk1-deficient mice display elevated anxiety-like behavior and noradrenergic abnormalities.
Katayama, K; Yamada, K; Ornthanalai, V G; Inoue, T; Ota, M; Murphy, N P; Aruga, J
2010-02-01
Mutations in SLITRK1 are found in patients with Tourette's syndrome and trichotillomania. SLITRK1 encodes a transmembrane protein containing leucine-rich repeats that is produced predominantly in the nervous system. However, the role of this protein is largely unknown, except that it can modulate neurite outgrowth in vitro. To clarify the role of Slitrk1 in vivo, we developed Slitrk1-knockout mice and analyzed their behavioral and neurochemical phenotypes. Slitrk1-deficient mice exhibited elevated anxiety-like behavior in the elevated plus-maze test as well as increased immobility time in forced swimming and tail suspension tests. Neurochemical analysis revealed that Slitrk1-knockout mice had increased levels of norepinephrine and its metabolite 3-methoxy-4-hydroxyphenylglycol. Administration of clonidine, an alpha2-adrenergic agonist that is frequently used to treat patients with Tourette's syndrome, attenuated the anxiety-like behavior of Slitrk1-deficient mice in the elevated plus-maze test. These results lead us to conclude that noradrenergic mechanisms are involved in the behavioral abnormalities of Slitrk1-deficient mice. Elevated anxiety due to Slitrk1 dysfunction may contribute to the pathogenesis of neuropsychiatric diseases such as Tourette's syndrome and trichotillomania.
Leavitt, V M; De Meo, E; Riccitelli, G; Rocca, M A; Comi, G; Filippi, M; Sumowski, J F
2015-11-01
Elevated body temperature was recently reported for the first time in patients with relapsing-remitting multiple sclerosis (RRMS) relative to healthy controls. In addition, warmer body temperature was associated with worse fatigue. These findings are highly novel, may indicate a novel pathophysiology for MS fatigue, and therefore warrant replication in a geographically separate sample. Here, we investigated body temperature and its association to fatigue in an Italian sample of 44 RRMS patients and 44 age- and sex-matched healthy controls. Consistent with our original report, we found elevated body temperature in the RRMS sample compared to healthy controls. Warmer body temperature was associated with worse fatigue, thereby supporting the notion of endogenous temperature elevations in patients with RRMS as a novel pathophysiological factor underlying fatigue. Our findings highlight a paradigm shift in our understanding of the effect of heat in RRMS, from exogenous (i.e., Uhthoff's phenomenon) to endogenous. Although randomized controlled trials of cooling treatments (i.e., aspirin, cooling garments) to reduce fatigue in RRMS have been successful, consideration of endogenously elevated body temperature as the underlying target will enhance our development of novel treatments.
Temperature dependent relaxation of interface-states in graphene on SiO2
NASA Astrophysics Data System (ADS)
Singh, Anil Kumar; Gupta, Anjan Kumar
2018-04-01
We have studied the evolution of resistance relaxation with temperature in graphene field effect transistor on SiO2. At room temperature, piranha-cleaned-SiO2 devices show slow resistance relaxation while IPA-cleaned-SiO2 devices do not. With cooling the former devices show a decrease in magnitude and time constant of the slow relaxation and it becomes negligible at 250K. Relaxation study at elevated temperature of the IPA-cleaned devices show a gate voltage polarity dependent time constant with respect to the charge neutrality point but it remains almost independent of temperature. The magnitude of relaxation increases with temperature. Further, after annealing at elevated temperature, we found that the relaxation times become independent of gate voltage polarity and its magnitude becomes very small. These observations are discussed using increase in diffusion of interface-species with temperature.
NASA Astrophysics Data System (ADS)
Krassovski, M.; Hanson, P. J.; Riggs, J. S.; Nettles, W. R., IV
2017-12-01
Climate change studies are one of the most important aspects of modern science and related experiments are getting bigger and more complex. One such experiment is the Spruce and Peatland Responses Under Climatic and Environmental Change experiment (SPRUCE, http://mnspruce.ornl.gov) conducted in in northern Minnesota, 40 km north of Grand Rapids, in the USDA Forest Service Marcell Experimental Forest (MEF). The SPRUCE experimental mission is to assess ecosystem-level biological responses of vulnerable, high carbon terrestrial ecosystems to a range of climate warming manipulations and an elevated CO2 atmosphere. This manipulation experiment generates a lot of observational data and requires a reliable onsite data collection system, dependable methods to transfer data to a robust scientific facility, and real-time monitoring capabilities. This presentation shares our experience of establishing near real time/low latency data collection and monitoring system using satellite communication.
Sinzinger, H; Lupattelli, G; Chehne, F; Oguogho, A; Furberg, C D
2001-08-01
Muscle pains with or without CK-elevation are among the most frequently observed side-effects in patients with hyperlipoproteinemia on various statins. The pathophysiological background, however, remains obscure. We examined isoprostane 8-epi-PGF2alpha, a marker of in-vivo oxidation injury, in plasma, serum and urine in these patients at baseline, when muscle problems manifested and different time intervals after withdrawing the respective statin. A healthy control group and a group of untreated patients with hyperlipoproteinemia were run as controls. The majority of patients with muscular side-effects show elevated 8-epi-PGF2alpha in plasma and urine, whereas serum values were elevated only to a lesser extent. Stopping statin therapy or successfully changing to another member of this family of compounds resulted in a normalization of the values in all patients. These findings indicate a significant involvement of oxidative injury in the muscular side-effects of statins in patients suffering from hyperlipoproteinemia.
Kaehler, James A.
1984-01-01
An improvement in a system and method of controlling heliostat in which the heliostat is operable in azimuth and elevation by respective stepper motors and including the respective steps or means for calculating the position for the heliostat to be at a commanded position, determining the number of steps in azimuth and elevation for each respective motor to get to the commanded position and energizing both the azimuth and elevation stepper motors to run in parallel until predetermined number of steps away from the closest commanded position in azimuth and elevation so that the closest position has been achieved, and thereafter energizing only the remaining motor to bring it to its commanded position. In this way, the heliostat can be started from a stowed position in the morning and operated by a computer means to its commanded position and kept correctly oriented throughout the day using only the time of the day without requiring the usual sensors and feedback apparatus. A computer, or microprocessor, can then control a plurality of many heliostats easily and efficiently throughout the day.
Czyz, E. K.; Horwitz, A. G.; Eisenberg, D.; Kramer, A.; King, C.A.
2013-01-01
Research objectives This study sought to describe self-reported barriers to professional help seeking among college students who are at elevated suicide risk and determine if these barriers vary by demographic and clinical characteristics. Participants Participants were 165 non-treatment seekers recruited as part of a web-based treatment linkage intervention for college students at elevated suicide risk (from September 2010 through December 2011). Methods Data were collected using web-based questionnaires. Two coders coded students’ responses to an open-ended question about reasons for not seeking professional help. Results The most commonly reported barriers included: perception that treatment is not needed (66%); lack of time (26.8%); preference for self-management (18%). Stigma was mentioned by only 12% of students. There were notable differences based on gender, race, and severity of depression and alcohol abuse. Conclusions Efforts aimed at reaching students at elevated risk for suicidal behavior should be particularly sensitive to these commonly described barriers. PMID:24010494
Jubb, A. M.; Jiao, Y.; Eres, Gyula; ...
2016-02-15
Here we demonstrate large area arrays of elevated gold ellipse dimers with precisely controlled gaps for use as sensitive and highly controllable surface enhanced Raman scattering (SERS) substrates. The significantly enhanced Raman signal observed with SERS arises from both localized and long range plasmonic effects. By controlling the geometry of a SERS substrate, in this case the size and aspect ratio of individual ellipses, the plasmon resonance can be tuned in a broad wavelength range, providing a method for designing the response of SERS substrates at different excitation wavelengths. Plasmon effects exhibited by the elevated gold ellipse dimer substrates aremore » also demonstrated and confirmed through finite difference time domain (FDTD) simulations. A plasmon resonance red shift with an increase of the ellipse aspect ratio is observed, allowing systematic control of the resulting SERS signal intensity. Optimized elevated ellipse dimer substrates with 10±2 nm gaps exhibit uniform SERS enhancement factors on the order of 10 9 for adsorbed p-mercaptoaniline molecules.« less
Elevated temperature crack growth
NASA Technical Reports Server (NTRS)
Kim, K. S.; Vanstone, R. H.
1992-01-01
The purpose of this program was to extend the work performed in the base program (CR 182247) into the regime of time-dependent crack growth under isothermal and thermal mechanical fatigue (TMF) loading, where creep deformation also influences the crack growth behavior. The investigation was performed in a two-year, six-task, combined experimental and analytical program. The path-independent integrals for application to time-dependent crack growth were critically reviewed. The crack growth was simulated using a finite element method. The path-independent integrals were computed from the results of finite-element analyses. The ability of these integrals to correlate experimental crack growth data were evaluated under various loading and temperature conditions. The results indicate that some of these integrals are viable parameters for crack growth prediction at elevated temperatures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Houpt, K.A.; Essick, L.A.; Shaw, E.B.
1988-01-01
When observed in their home cages, cats fed commercial tuna fish cat food were less active, vocalized less, and spent more time on the floor and more time eating than cats fed commercial beef cat food. There were no differences in response to human handling between the two groups. There were no differences in learning ability on a two-choice point maze or in reversal learning in the same maze between beef- and tuna-fed cats. The behavior of the groups differed in a 15-min open field test only in the number of toys contacted. Cats fed the tuna had elevated tissuemore » levels of mercury and selenium.« less
Sukhotnik, Igor; Voskoboinik, Katya; Lurie, Michael; Bejar, Yakov; Coran, Arnold G; Mogilner, Jorge G
2009-10-01
The objective of this study was to examine the relationship between time of reperfusion and bax/bcl-2-dependent germ cell apoptosis after testicular ischemia-reperfusion injury in the rat. In ischemic testis, bax/bcl-2 ratio did not change significantly, and the elevation of germ cell apoptosis was not marked; in the contralateral testis, germ cell apoptosis increased after 6 hours of reperfusion, achieved statistical significance after 24 hours, and decreased after 72 hours of reperfusion and was initiated by decreased bcl-2 messenger RNA levels and elevated bax/bcl-2 ratio within the first 6 hours of reperfusion.
NASA Astrophysics Data System (ADS)
Gladshteyn, V. I.; Troitskiy, A. I.
2017-01-01
Research of a metal of the stop valve case (SVC) of the K-300-23.5 LMZ turbine (steel grade 15Kh1M1FL), destroyed after operation for 331000 hours, is performed. It's chemical composition and properties are determined as follows: a short-term mechanical tensile stress at 20°C and at elevated temperature, critical temperature, fragility, critical crack opening at elevated temperature, and long-term strength. Furthermore, nature of the microstructure, packing density of carbide particles and their size, and chemical composition of carbide sediment are estimated. A manifestation of metal properties for the main case components by comparison with a forecast of the respective characteristics made for the operating time of 331000 hours is tested. Property-time relationships are built for the forecast using statistical treatment of the test results for the samples cut out from more than 300 parts. Representativeness of the research results is proved: the statistical treatment of their differences are within the range of ±5%. It has been found that, after 150000 hours of operation, only the tensile strength insignificantly depends on the operating time at 20°C, whereas indicators of strength at elevated temperature significantly reduce, depending on the operating time. A brittle-to-ductile transition temperature (BDTT) raises, a critical notch opening changes in a complicated way, a long-term strength reduces. It has been found empirically that the limit of a long-term strength of the SVC metal at 540°C and the operating time of 105 hours is almost 1.6 times less than the required value in the as-delivered state. It is possible to evaluate a service life of the operating valves with the operating time of more than 330000 hours with respect to the long-term strength of the metal taking into account the actual temperature and stress. Guidelines for the control of similar parts are provided.
Emergency Plan for Sandy Lake Dam and Reservoir
1987-06-01
UTFLOW 0I J" I - " -I I 0 5 I0 15 20 25 30 TIME IN DAYS p CT WITHOUT FAILURE ELEVATION HYDROGRAPHS -1235 -!230 -1225 >z DESIGN POOL ELEVATION iui LiL...harrowing, fertilizing , digging sprigs, hauling sprigs, scattering sprigs, disking, seeding and watering. Typical crew: Riprap - 1 crew leader and 6 to...LEVEL Name of Resource Type of Resource Address Phone Number Brisson Pump Company Pump Distributor 2359 E. Cowern Place (612) 777-3317 N. St. Paul, MN
2014-04-01
colonization may also limit the potential for intra-island speciation and adaptive radiations (MacArthur and Wilson 1963, Zink et al. 1996, Chubb et...et al. 2012), and nitrogen stable isotope ratios of algae, macroinvertebrates (i.e., gastropods ) and A. stamineus were used as a time-integrated...elevations are a genetic subset of coastal and lower elevation populations due to adaptive differences in climbing ability and predator avoidance
Short Time Elevated Temperature Tensile Properties and Notch Toughness of Some Chromium-Iron Alloys
1957-06-07
toughness of matcrials A, B, and C was determined by using subsize V-notch Charpy Specimens, 1 inch long by 0.197 inch square prepared with their...elevated temperature tensile tests and V-notch Charpy imapact tests of som recently developed alloys with 4O,’a and 50,,1 ohromiuma are presented in this...lengths parallel to the longitudinal uxis of the alloy bars. In addition, some standard size V-notch Charpy specimens waro mach-ined from material B, for
Pulsations, interpulsations, and sea-floor spreading.
NASA Technical Reports Server (NTRS)
Pessagno, E. A., Jr.
1973-01-01
It is postulated that worldwide transgressions (pulsations) and regressions (interpulsations) through the course of geologic time are related to the elevation and subsidence of oceanic ridge systems and to sea-floor spreading. Two multiple working hypotheses are advanced to explain major transgressions and regressions and the elevation and subsidence of oceanic ridge systems. One hypothesis interrelates the sea-floor spreading hypothesis to the hypothesis of sub-Mohorovicic serpentinization. The second hypothesis relates the sea-floor spreading hypothesis to a hypothesis involving thermal expansion and contraction.
Trends in 1970-2010 southern California surface maximum temperatures: extremes and heat waves
NASA Astrophysics Data System (ADS)
Ghebreegziabher, Amanuel T.
Daily maximum temperatures from 1970-2010 were obtained from the National Climatic Data Center (NCDC) for 28 South Coast Air Basin (SoCAB) Cooperative Network (COOP) sites. Analyses were carried out on the entire data set, as well as on the 1970-1974 and 2006-2010 sub-periods, including construction of spatial distributions and time-series trends of both summer-average and annual-maximum values and of the frequency of two and four consecutive "daytime" heat wave events. Spatial patterns of average and extreme values showed three areas consistent with climatological SoCAB flow patterns: cold coastal, warm inland low-elevation, and cool further-inland mountain top. Difference (2006-2010 minus 1970-1974) distributions of both average and extreme-value trends were consistent with the shorter period (1970-2005) study of previous study, as they showed the expected inland regional warming and a "reverse-reaction" cooling in low elevation coastal and inland areas open to increasing sea breeze flows. Annual-extreme trends generally showed cooling at sites below 600 m and warming at higher elevations. As the warming trends of the extremes were larger than those of the averages, regional warming thus impacts extremes more than averages. Spatial distributions of hot-day frequencies showed expected maximum at inland low-elevation sites. Regional warming again thus induced increases at both elevated-coastal areas, but low-elevation areas showed reverse-reaction decreases.
Water table variability and runoff generation in an eroded peatland, South Pennines, UK
NASA Astrophysics Data System (ADS)
Daniels, S. M.; Agnew, C. T.; Allott, T. E. H.; Evans, M. G.
2008-10-01
SummaryHydrological monitoring in an eroded South Pennine peatland shows that persistent and frequent water table drawdowns occur at gully edge locations, defining a deeper and thicker acrotelm than is observed in intact peatlands (an erosional acrotelm). Antecedent water table elevation is a key control on the hydrological response to precipitation events, in particular runoff percent, the timing of peak discharges and maximum water table elevations. Significant discharge is generated whilst water table elevations are relatively low at gully edge locations, and this has a strong influence on flow pathways. Four characteristics of runoff response are recognised: (i) the rapid development of macropore/pipe flow at the start of the storm; (ii) peat rewetting, water table elevation increase and continued macropore/pipe flow; (iii) maximum water table elevations and peak stream discharge with throughflow occurring within the erosional acrotelm and rapid flow through the subsurface macropore/pipe network; (iv) rapidly declining water table elevations and stream flow following the cessation of rainfall. Gully edge peats provide a key linkage between the hillslope hydrological system and channel flow so that their influence on the hydrological functioning of the peatlands is disproportionate to their aerial extent within the catchment. Future climate change may lead to further degradation of the bogs and a reinforcement of the importance of erosion gullies to runoff generation and water quality.
Zanet, Stefania; Miglio, Giacomo; Ferrari, Caterina; Bassano, Bruno; Ferroglio, Ezio; von Hardenberg, Achaz
2017-01-01
Alpine marmots Marmota marmota occupy a narrow altitudinal niche within high elevation alpine environments. For animals living at such high elevations where resources are limited, parasitism represents a potential major cost in life history. Using occupancy models, we tested if marmots living at higher elevation have a reduced risk of being infected with gastro-intestinal helminths, possibly compensating the lower availability of resources (shorter feeding season, longer snow cover and lower temperature) than marmots inhabiting lower elevations. Detection probability of eggs and oncospheres of two gastro-intestinal helminthic parasites, Ascaris laevis and Ctenotaenia marmotae, sampled in marmot feces, was used as a proxy of parasite abundance. As predicted, the models showed a negative relationship between elevation and parasite detectability (i.e. abundance) for both species, while there appeared to be a negative effect of solar radiance only for C. marmotae. Site-occupancy models are used here for the first time to model the constrains of gastrointestinal parasitism on a wild species and the relationship existing between endoparasites and environmental factors in a population of free-living animals. The results of this study suggest the future use of site-occupancy models as a viable tool to account for parasite imperfect detection in eco-parasitological studies, and give useful insights to further investigate the hypothesis of the contribution of parasite infection in constraining the altitudinal niche of Alpine marmots.
Papp, Lauren M.; Pendry, Patricia; Adam, Emma K.
2010-01-01
In this study, the authors examined parent-adolescent cortisol associations in 45 families with adolescent children (24 girls; M age = 15.78 years, SD = 1.44 years). Family members’ salivary cortisol levels were measured 7 times a day on 2 typical weekdays. Family members provided reports of demographic and health variables, and adolescents rated parent-child relationship characteristics. After accounting for the effects of time of day and relevant demographic and health control variables on cortisol levels, hierarchical linear models indicated the presence of significant covariation over time in mother-adolescent cortisol (i.e., physiological synchrony). Furthermore, moderating tests revealed that mother-adolescent cortisol synchrony was strengthened among dyads characterized by mothers and adolescents spending more time together, and in families rated higher on levels of parent-youth shared activities and parental monitoring/supervision. Analysis of momentary characteristics indicated that maternal presence at the time of cortisol sampling lowered adolescent cortisol levels but did not account for mother-adolescent cortisol synchrony. Within-family physiological synchrony was amplified in momentary contexts of elevated maternal negative affect and elevated adolescent negative affect. PMID:20001147
Papp, Lauren M; Pendry, Patricia; Adam, Emma K
2009-12-01
In this study, the authors examined parent-adolescent cortisol associations in 45 families with adolescent children (24 girls; M age = 15.78 years, SD = 1.44 years). Family members' salivary cortisol levels were measured seven times a day on 2 typical weekdays. Family members provided reports of demographic and health variables, and adolescents rated parent-child relationship characteristics. After accounting for the effects of time of day and relevant demographic and health control variables on cortisol levels, hierarchical linear models indicated the presence of significant covariation over time in mother-adolescent cortisol (i.e., physiological synchrony). Furthermore, moderating tests revealed that mother-adolescent cortisol synchrony was strengthened among dyads characterized by mothers and adolescents spending more time together, and in families rated higher on levels of parent-youth shared activities and parental monitoring or supervision. Analysis of momentary characteristics indicated that maternal presence at the time of cortisol sampling lowered adolescent cortisol levels but did not account for mother-adolescent cortisol synchrony. Within-family physiological synchrony was amplified in momentary contexts of elevated maternal negative affect and elevated adolescent negative affect.
NASA Astrophysics Data System (ADS)
Schwartz, M. A.; Hall, A. D.; Sun, F.; Walton, D.; Berg, N.
2015-12-01
Hybrid dynamical-statistical downscaling is used to produce surface runoff timing projections for California's Sierra Nevada, a high-elevation mountain range with significant seasonal snow cover. First, future climate change projections (RCP8.5 forcing scenario, 2081-2100 period) from five CMIP5 global climate models (GCMs) are dynamically downscaled. These projections reveal that future warming leads to a shift toward earlier snowmelt and surface runoff timing throughout the Sierra Nevada region. Relationships between warming and surface runoff timing from the dynamical simulations are used to build a simple statistical model that mimics the dynamical model's projected surface runoff timing changes given GCM input or other statistically-downscaled input. This statistical model can be used to produce surface runoff timing projections for other GCMs, periods, and forcing scenarios to quantify ensemble-mean changes, uncertainty due to intermodel variability and consequences stemming from choice of forcing scenario. For all CMIP5 GCMs and forcing scenarios, significant trends toward earlier surface runoff timing occur at elevations below 2500m. Thus, we conclude that trends toward earlier surface runoff timing by the end-of-the-21st century are inevitable. The changes to surface runoff timing diagnosed in this study have implications for many dimensions of climate change, including impacts on surface hydrology, water resources, and ecosystems.
Khot, Umesh N; Johnson-Wood, Michele L; Geddes, Jason B; Ramsey, Curtis; Khot, Monica B; Taillon, Heather; Todd, Randall; Shaikh, Saeed R; Berg, William J
2009-07-26
The impact of reducing door-to-balloon time on hospital revenues, costs, and net income is unknown. We prospectively determined the impact on hospital finances of (1) emergency department physician activation of the catheterization lab and (2) immediate transfer of the patient to an immediately available catheterization lab by an in-house transfer team consisting of an emergency department nurse, a critical care unit nurse, and a chest pain unit nurse. We collected financial data for 52 consecutive ST-elevation myocardial infarction patients undergoing emergency percutaneous intervention from October 1, 2004-August 31, 2005 and compared this group to 80 consecutive ST-elevation myocardial infarction patients from September 1, 2005-June 26, 2006 after protocol implementation. Per hospital admission, insurance payments (hospital revenue) decreased ($35,043 +/- $36,670 vs. $25,329 +/- $16,185, P = 0.039) along with total hospital costs ($28,082 +/- $31,453 vs. $18,195 +/- $9,242, P = 0.009). Hospital net income per admission was unchanged ($6962 vs. $7134, P = 0.95) as the drop in hospital revenue equaled the drop in costs. For every $1000 reduction in total hospital costs, insurance payments (hospital revenue) dropped $1077 for private payers and $1199 for Medicare/Medicaid. A decrease in hospital charges ($70,430 +/- $74,033 vs. $53,514 +/- $23,378, P = 0.059), diagnosis related group relative weight (3.7479 +/- 2.6731 vs. 2.9729 +/- 0.8545, P = 0.017) and outlier payments with hospital revenue>$100,000 (7.7% vs. 0%, P = 0.022) all contributed to decreasing ST-elevation myocardial infarction hospitalization revenue. One-year post-discharge financial follow-up revealed similar results: Insurance payments: $49,959 +/- $53,741 vs. $35,937 +/- $23,125, P = 0.044; Total hospital costs: $39,974 +/- $37,434 vs. $26,778 +/- $15,561, P = 0.007; Net Income: $9984 vs. $9159, P = 0.855. All of the financial benefits of reducing door-to-balloon time in ST-elevation myocardial infarction go to payers both during initial hospitalization and after one-year follow-up. ClinicalTrials.gov ID: NCT00800163.
NASA Astrophysics Data System (ADS)
Shean, D. E.; Christianson, K.; Larson, K. M.; Ligtenberg, S.; Joughin, I. R.; Smith, B.; Stevens, C.
2016-12-01
In recent decades, Pine Island Glacier (PIG) has experienced marked retreat, speedup and thinning due to ice-shelf basal melt, internal ice-stream instability and feedbacks between these processes. In an effort to constrain recent ice-stream dynamics and evaluate potential causes of retreat, we analyzed 2008-2010 and 2012-2014 GPS records for PIG. We computed time series of horizontal velocity, strain rate, multipath-based antenna height, surface elevation, and Lagrangian elevation change (Dh/Dt). These data provide validation for complementary high-resolution WorldView stereo digital elevation model (DEM) records, with sampled DEM vertical error of 0.7 m. The GPS antenna height time series document a relative surface elevation increase of 0.7-1.0 m/yr, which is consistent with estimated surface mass balance (SMB) of 0.7-0.9 m.w.e./yr from RACMO2.3 and firn compaction rates from the IMAU-FDM dynamic firn model. An abrupt 0.2-0.3 m surface elevation decrease due to surface melt and/or greater near-surface firn compaction is observed during a period of warm atmospheric temperatures from December 2012 to January 2013. Observed surface Dh/Dt for all PIG shelf sites is highly linear with trends of -1 to -4 m/yr and <0.4 m residuals. Similar Dh/Dt estimates with reduced variability are obtained after removing expected downward GPS pole base velocity from observed GPS antenna Dh/Dt. Estimated Dh/Dt basal melt rates are 10 to 40 m/yr for the outer PIG shelf and 4 m/yr for the South shelf. These melt rates are similar to those derived from ice-bottom acoustic ranging, phase-sensitive ice-penetrating radar, and high-resolution stereo DEM records. The GPS/DEM records document higher melt rates within and near transverse surface depressions and rifts associated with longitudinal extension. Basal melt rates for the 2012-2014 period show limited temporal variability, despite significant change in ocean heat content. This suggests that sub-shelf melt rates are less sensitive to ocean heat content than previously reported, at least for these locations and time periods.
Circulating microparticle levels are reduced in patients with ARDS.
Shaver, Ciara M; Woods, Justin; Clune, Jennifer K; Grove, Brandon S; Wickersham, Nancy E; McNeil, J Brennan; Shemancik, Gregory; Ware, Lorraine B; Bastarache, Julie A
2017-05-25
It is unclear how to identify which patients at risk for acute respiratory distress syndrome (ARDS) will develop this condition during critical illness. Elevated microparticle (MP) concentrations in the airspace during ARDS are associated with activation of coagulation and in vitro studies have demonstrated that MPs contribute to acute lung injury, but the significance of MPs in the circulation during ARDS has not been well studied. The goal of the present study was to test the hypothesis that elevated levels of circulating MPs could prospectively identify critically ill patients who will develop ARDS and that elevated circulating MPs are associated with poor clinical outcomes. A total of 280 patients with platelet-poor plasma samples from the prospective Validating Acute Lung Injury biomarkers for Diagnosis (VALID) cohort study were selected for this analysis. Demographics and clinical data were obtained by chart review. MP concentrations in plasma were measured at study enrollment on intensive care unit (ICU) day 2 and on ICU day 4 by MP capture assay. Activation of coagulation was measured by plasma recalcification (clot) times. ARDS developed in 90 of 280 patients (32%) in the study. Elevated plasma MP concentrations were associated with reduced risk of developing ARDS (odds ratio (OR) 0.70 per 10 μM increase in MP concentration, 95% CI 0.50-0.98, p = 0.042), but had no significant effect on hospital mortality. MP concentration was greatest in patients with sepsis, pneumonia, or aspiration as compared with those with trauma or receiving multiple blood transfusions. MP levels did not significantly change over time. The inverse association of MP levels with ARDS development was most striking in patients with sepsis. After controlling for age, presence of sepsis, and severity of illness, higher MP concentrations were independently associated with a reduced risk of developing ARDS (OR 0.69, 95% CI 0.49-0.98, p = 0.038). MP concentration was associated with reduced plasma recalcification time. Elevated levels of circulating MPs are independently associated with a reduced risk of ARDS in critically ill patients. Whether this is due to MP effects on systemic coagulation warrants further investigation.
Murray, T J; Ellsworth, D S; Tissue, D T; Riegler, M
2013-05-01
Understanding the direct and indirect effects of elevated [CO2 ] and temperature on insect herbivores and how these factors interact are essential to predict ecosystem-level responses to climate change scenarios. In three concurrent glasshouse experiments, we measured both the individual and interactive effects of elevated [CO2 ] and temperature on foliar quality. We also assessed the interactions between their direct and plant-mediated effects on the development of an insect herbivore of eucalypts. Eucalyptus tereticornis saplings were grown at ambient or elevated [CO2 ] (400 and 650 μmol mol(-1) respectively) and ambient or elevated ( + 4 °C) temperature for 10 months. Doratifera quadriguttata (Lepidoptera: Limacodidae) larvae were feeding directly on these trees, on their excised leaves in a separate glasshouse, or on excised field-grown leaves within the temperature and [CO2 ] controlled glasshouse. To allow insect gender to be determined and to ensure that any sex-specific developmental differences could be distinguished from treatment effects, insect development time and consumption were measured from egg hatch to pupation. No direct [CO2 ] effects on insects were observed. Elevated temperature accelerated larval development, but did not affect leaf consumption. Elevated [CO2 ] and temperature independently reduced foliar quality, slowing larval development and increasing consumption. Simultaneously increasing both [CO2 ] and temperature reduced these shifts in foliar quality, and negative effects on larval performance were subsequently ameliorated. Negative nutritional effects of elevated [CO2 ] and temperature were also independently outweighed by the direct positive effect of elevated temperature on larvae. Rising [CO2 ] and temperature are thus predicted to have interactive effects on foliar quality that affect eucalypt-feeding insects. However, the ecological consequences of these interactions will depend on the magnitude of concurrent temperature rise and its direct effects on insect physiology and feeding behaviour. © 2013 Blackwell Publishing Ltd.
NASA Astrophysics Data System (ADS)
Kulloli, R. N.; Kumar, S.
2014-11-01
Commiphora wightii (Arnt.) Bhand., is an important medicinal plant of Indian Medicine System (IMS) since ancient time. It is used in different ailments of obesity, arthritis, rheumatism and high cholesterol. Due to overexploitation its natural populations declined to large extent. IUCN has put it under Data Deficient (DD) category due to lack of data on its extent of occurrence in nature. Hence, the study was carried out using MaxEnt distribution modelling algorithm to estimate its geographic distribution and to identify potential habitats for its reintroduction. For modelling employed 68 presence locality data, 19 bioclimatic variables, Normalize Difference Vegetation Index (NDVI) and elevation data. These were tested for multicollinearity and those variables having r-value less than 0.8 were selected for further analysis, which was carried out in two ways i) Bioclimatic variables and elevation; ii) NDVI and elevation. Area Under the Curve (AUC) in both analysis was above 0.9 for all variables, indicating very high accuracy of prediction. Variables governing distribution of C. wightii in the analysis using bioclimatic and elevation data set are precipitation seasonality (56.6 %), annual precipitation (16.4 %) and elevation (14.7 %). Extent of occurrence of C.wightii predicted by model closely matched in the districts of Jaisalmer and Barmer. In the second analysis elevation (48.3 %), NDVI of June (11.1 %) and August (11.2 %) contributed for NDVI and Elevation data set. NDVI of June corresponds to its leafing phase while NDVI of August to flowering phase. Area of its occurrence predicted for NDVI and elevation data set are Bikaner, Churu, Jhunjhunun some part of Jodhpur which are completely sandy, where C. wightii is totally absent. Extent of occurrence was also validated in ground survey. Potential areas for its reintroduction were identified as Jaisalmer and Barmer districts in Indian arid zone.
Qiao, Yunzhou; Liu, Huiling; Kellomäki, Seppo; Peltola, Heli; Liu, Yueyan; Dong, Baodi; Shi, Changhai; Zhang, Huizhen; Zhang, Chao; Gong, Jinnan; Si, Fuyan; Li, Dongxiao; Zheng, Xin; Liu, Mengyu
2014-01-01
Under the changing climate, asymmetric warming pattern would be more likely during day and night time, instead of symmetric one. Concurrently, the growth responses and water use of plants may be different compared with those estimated based on symmetric warming. In this work, it was compared with the effects of symmetric (ETs) and asymmetric (ETa) elevation of temperature alone, and in interaction with elevated carbon dioxide concentration (EC), on the grain yield (GY) and evapotranspiration in winter wheat (Triticum aestivum L.) based on pot experiment in the North China Plain (NCP). The experiment was carried out in six enclosed-top chambers with following climate treatments: (1) ambient temperature and ambient CO2 (CON), (2) ambient temperature and elevated CO2 (EC), (3) elevated temperature and ambient CO2 (ETs; ETa), and (4) elevated temperature and elevated CO2 (ECETs, ECETa). In symmetric warming, temperature was increased by 3°C and in asymmetric one by 3.5°C during night and 2.5°C during daytime, respectively. As a result, GY was in ETa and ETs 15.6 (P < 0.05) and 10.3% (P < 0.05) lower than that in CON. In ECETs and ECETa treatments, GY was 14.9 (P < 0.05) and 9.1% (P < 0.05) higher than that in CON. Opposite to GY, evapotranspiration was 7.8 (P < 0.05) and 17.9% (P < 0.05) higher in ETa and ETs treatments and 7.2 (P < 0.05) and 2.1% (P > 0.05) lower in ECETs and ECETa treatments compared with CON. Thus, GY of wheat could be expected to increase under the changing climate with concurrent elevation of CO2 and temperature as a result of increased WUE under the elevated CO2. However, the gain would be lower under ETa than that estimated based on ETs due to higher evapotranspiration. PMID:24963392
Qiao, Yunzhou; Liu, Huiling; Kellomäki, Seppo; Peltola, Heli; Liu, Yueyan; Dong, Baodi; Shi, Changhai; Zhang, Huizhen; Zhang, Chao; Gong, Jinnan; Si, Fuyan; Li, Dongxiao; Zheng, Xin; Liu, Mengyu
2014-05-01
Under the changing climate, asymmetric warming pattern would be more likely during day and night time, instead of symmetric one. Concurrently, the growth responses and water use of plants may be different compared with those estimated based on symmetric warming. In this work, it was compared with the effects of symmetric (ETs) and asymmetric (ETa) elevation of temperature alone, and in interaction with elevated carbon dioxide concentration (EC), on the grain yield (GY) and evapotranspiration in winter wheat (Triticum aestivum L.) based on pot experiment in the North China Plain (NCP). The experiment was carried out in six enclosed-top chambers with following climate treatments: (1) ambient temperature and ambient CO2 (CON), (2) ambient temperature and elevated CO2 (EC), (3) elevated temperature and ambient CO2 (ETs; ETa), and (4) elevated temperature and elevated CO2 (ECETs, ECETa). In symmetric warming, temperature was increased by 3°C and in asymmetric one by 3.5°C during night and 2.5°C during daytime, respectively. As a result, GY was in ETa and ETs 15.6 (P < 0.05) and 10.3% (P < 0.05) lower than that in CON. In ECETs and ECETa treatments, GY was 14.9 (P < 0.05) and 9.1% (P < 0.05) higher than that in CON. Opposite to GY, evapotranspiration was 7.8 (P < 0.05) and 17.9% (P < 0.05) higher in ETa and ETs treatments and 7.2 (P < 0.05) and 2.1% (P > 0.05) lower in ECETs and ECETa treatments compared with CON. Thus, GY of wheat could be expected to increase under the changing climate with concurrent elevation of CO2 and temperature as a result of increased WUE under the elevated CO2. However, the gain would be lower under ETa than that estimated based on ETs due to higher evapotranspiration.
Donnelly, Alison; Craigon, Jim; Black, Colin R.; Colls, Jeremy J.; Landon, Geoff
2001-04-01
This study examined the impact of season-long exposure to elevated carbon dioxide (CO2) and ozone (O3), individually and in combination, on leaf chlorophyll content and gas exchange characteristics in potato (Solanum tuberosum L. cv. Bintje). Plants grown in open-top chambers were exposed to three CO2 (ambient, 550 and 680 µmol mol-1) and two O3 treatments (ambient and elevated; 25 and 65 nmol mol-1, 8 h day-1 means, respectively) between crop emergence and maturity; plants were also grown in unchambered field plots. Non-destructive measurements of chlorophyll content and visible foliar injury were made for all treatments at 2-week intervals between 43 and 95 days after emergence. Gas exchange measurements were made for all except the intermediate 550 µmol mol-1 CO2 treatment. Season-long exposure to elevated O3 under ambient CO2 reduced chlorophyll content and induced extensive visible foliar damage, but had little effect on net assimilation rate or stomatal conductance. Elevated CO2 had no significant effect on chlorophyll content, but greatly reduced the damaging impact of O3 on chlorophyll content and visible foliar damage. Light-saturated assimilation rates for leaves grown under elevated CO2 were consistently lower when measured under either elevated or ambient CO2 than in equivalent leaves grown under ambient CO2. Analysis of CO2 response curves revealed that CO2-saturated assimilation rate, maximum rates of carboxylation and electron transport and respiration decreased with time. CO2-saturated assimilation rate was reduced by elevated O3 during the early stages of the season, while respiration was significantly greater under elevated CO2 as the crop approached maturity. The physiological origins of these responses and their implications for the performance of potato in a changing climate are discussed.
Zahrieh, David; Young, Sean G.; Oleson, Jacob; Ryckman, Kelli K.; Wels, Brian; Simmons, Donald L.; Saftlas, Audrey
2017-01-01
Lead in maternal blood can cross the placenta and result in elevated blood lead levels in newborns, potentially producing negative effects on neurocognitive function, particularly if combined with childhood lead exposure. Little research exists, however, into the burden of elevated blood lead levels in newborns, or the places and populations in which elevated lead levels are observed in newborns, particularly in rural settings. Using ~2300 dried bloods spots collected within 1–3 days of birth among Iowa newborns, linked with the area of mother’s residence at the time of birth, we examine the spatial patterns of elevated (>5 μg/dL) blood lead levels and the ecological-level predictors of elevated blood lead levels. We find that one in five newborns exceed the 5 μg/dL action level set by the US Centers for Disease Control & Prevention (CDC). Bayesian spatial zero inflated regression indicates that elevated blood lead in newborns is associated with areas of increased pre-1940s housing and childbearing-age women with low educational status in both rural and urban settings. No differences in blood lead levels or the proportion of children exceeding 5 μg/dL are observed between urban and rural maternal residence, though a spatial cluster of elevated blood lead is observed in rural counties. These characteristics can guide the recommendation for testing of infants at well-baby appointments in places where risk factors are present, potentially leading to earlier initiation of case management. The findings also suggest that rural populations are at as great of risk of elevated blood lead levels as are urban populations. Analysis of newborn dried blood spots is an important tool for lead poisoning surveillance in newborns and can direct public health efforts towards specific places and populations where lead testing and case management will have the greatest impact. PMID:28520816
The impact of lidar elevation uncertainty on mapping intertidal habitats on barrier islands
Enwright, Nicholas M.; Wang, Lei; Borchert, Sinéad M.; Day, Richard H.; Feher, Laura C.; Osland, Michael J.
2018-01-01
While airborne lidar data have revolutionized the spatial resolution that elevations can be realized, data limitations are often magnified in coastal settings. Researchers have found that airborne lidar can have a vertical error as high as 60 cm in densely vegetated intertidal areas. The uncertainty of digital elevation models is often left unaddressed; however, in low-relief environments, such as barrier islands, centimeter differences in elevation can affect exposure to physically demanding abiotic conditions, which greatly influence ecosystem structure and function. In this study, we used airborne lidar elevation data, in situ elevation observations, lidar metadata, and tide gauge information to delineate low-lying lands and the intertidal wetlands on Dauphin Island, a barrier island along the coast of Alabama, USA. We compared three different elevation error treatments, which included leaving error untreated and treatments that used Monte Carlo simulations to incorporate elevation vertical uncertainty using general information from lidar metadata and site-specific Real-Time Kinematic Global Position System data, respectively. To aid researchers in instances where limited information is available for error propagation, we conducted a sensitivity test to assess the effect of minor changes to error and bias. Treatment of error with site-specific observations produced the fewest omission errors, although the treatment using the lidar metadata had the most well-balanced results. The percent coverage of intertidal wetlands was increased by up to 80% when treating the vertical error of the digital elevation models. Based on the results from the sensitivity analysis, it could be reasonable to use error and positive bias values from literature for similar environments, conditions, and lidar acquisition characteristics in the event that collection of site-specific data is not feasible and information in the lidar metadata is insufficient. The methodology presented in this study should increase efficiency and enhance results for habitat mapping and analyses in dynamic, low-relief coastal environments.
Holmstrand, Ericka C.; Lund, David; Cherian, Ajeesh Koshy; Wright, Jane; Martin, Rolicia F.; Ennis, Elizabeth A.; Stanwood, Gregg D.; Sarter, Martin; Blakely, Randy D.
2014-01-01
The hemicholinium-3 (HC-3) sensitive, high-affinity choline transporter (CHT) sustains cholinergic signaling via the presynaptic uptake of choline derived from dietary sources or from acetylcholinesterase (AChE)-mediated hydrolysis of acetylcholine (ACh). Loss of cholinergic signaling capacity is associated with cognitive and motor deficits in humans and in animal models. Whereas genetic elimination of CHT has revealed the critical nature of CHT in maintaining ACh stores and sustaining cholinergic signaling, the consequences of elevating CHT expression have yet to be studied. Using bacterial artificial chromosome (BAC)-mediated transgenic methods, we generated mice with integrated additional copies of the mouse Slc5a7 gene. BAC–CHT mice are viable, appear to develop normally, and breed at wild-type (WT) rates. Biochemical studies revealed a 2 to 3-fold elevation in CHT protein levels in the CNS and periphery, paralleled by significant increases in [3H]HC-3 binding and synaptosomal choline transport activity. Elevations of ACh in the BAC–CHT mice occurred without compensatory changes in the activity of either choline acetyltransferase (ChAT) or AChE. Immunohistochemistry for CHT in BAC–CHT brain sections revealed markedly elevated CHT expression in the cell bodies of cholinergic neurons and in axons projecting to regions known to receive cholinergic innervation. Behaviorally, BAC–CHT mice exhibited diminished fatigue and increased speeds on the treadmill test without evidence of increased strength. Finally, BAC–CHT mice displayed elevated horizontal activity in the open field test, diminished spontaneous alteration in the Y-maze, and reduced time in the open arms of the elevated plus maze. Together, these studies provide biochemical, pharmacological and behavioral evidence that CHT protein expression and activity can be elevated beyond that seen in wild-type animals. BAC–CHT mice thus represent a novel tool to examine both the positive and negative impact of constitutively elevated cholinergic signaling capacity. PMID:24274995
Quantification of soil losses from tourist trails - use of Digital Elevation Models
NASA Astrophysics Data System (ADS)
Tomczyk, Aleksandra
2010-05-01
Tourism impacts in protected mountain areas are one of the main concerns for land managers. Impact to environment is most visible at locations of highly concentrated activities like tourist trails, campsites etc. The main indicators of the tourist trail degradation are: vegetation loss (trampling of vegetation cover), change of vegetation type and composition, widening of the trails, muddiness and soil erosion. The last one is especially significant, since it can cause serious transformation of the land surface. Such undesirable changes cannot be repaired without high-cost management activities, and, in some cases they can made the trails difficult and unsafe to use. Scientific understanding of soil erosion related to human impact can be useful for more effective management of the natural protected areas. The aim of this study was to use of digital elevation models (DEMs) to precisely quantify of soil losses from tourist trails. In the study precise elevation data were gathered in several test fields of 4 by 5 m spatial dimension. Measurements were taken in 13 test fields, located in two protected natural areas in south Poland: Gorce National Park and Popradzki Landscape Park. The measuring places were located on trails characterized by different slope, type of vegetation and type of use. Each test field was established by four special marks, firmly dug into the ground. Elevation data were measured with the electronic total station. Irregular elevation points were surveying with essential elements of surrounding terrain surface being included. Moreover, surveys in fixed profile lines were done. For each test field a set of 30 measurements in control points has been collected and these data provide the base for verification of digital elevation models. Average density of the surveying was 70 points per square meter (1000 - 1500 elevation points per each test fields). Surveys in each test field were carried out in August and September of 2008, June 2009 and August 2009. Based on the gathered elevation data, several digital elevation models with spatial resolution 5 x 5 cm and 1 x 1 cm were generated. Subtraction of the DEMs from subsequent time periods gives the amount of material which was transported within the test fields and shows the spatial distribution of earth-surface changes. Spatial and temporal analysis of transformations of trail surfaces revealed that the changes are not evenly distributed neither in time nor space. In most of the test fields only the small portion of trail were subjected to distinct (more than 1 cm per year) erosion or accumulation. Moreover, degree of changes between June 2009 and August 2009 (3 months) was similar to the degree of changes between August - September 2008 and June 2009 (9 months). Main factors influence patterns of erosion are slope and type of use.
Feed intake and behavior of dairy goats when offered an elevated feed bunk.
Neave, Heather W; von Keyserlingk, Marina A G; Weary, Daniel M; Zobel, Gosia
2018-04-01
Goats are browsers and select vegetation at various heights when foraging. On commercial farms, dairy goats are typically fed from low-level feed bunks. The objective of this study was to determine how feed intake and feeding behavior vary when goats are offered feed at variable heights, with the potential of evaluating the benefits of offering an elevated feeder to dairy goats. Thirteen Saanen X dairy goats were housed in a home pen with a lying area of wood shavings, where they were pre-exposed for 24 d to 3 feeder heights designed to result in differences in head height while feeding: floor level (head lowered relative to body), head level (head level relative to body), and elevated level (head and neck angled upward). Nine groups of 3 goats each were randomly selected and housed for 24 h in a test pen identical to the home pen except that it contained 1 of each of the 3 feeder heights. Each feeder contained ad libitum chopped alfalfa silage and a top-dressed corn-based supplement, refreshed twice daily. Refusals from inside and under each feeder were weighed to calculate intake. Feed intake increased with increasing feeder height (mean ± SE; 0.18, 0.29, and 0.34 ± 0.04 kg of DM/goat for floor-level, head-level, and elevated-level feeders, respectively). Total feeding time did not vary with feeder height, but feeding rate tended to be faster at the elevated-level feeder (14.5 ± 2.1 g of DM/min) compared with head-level (9.2 ± 2.3 g of DM/min) and floor-level (8.9 ± 2.1 g of DM/min) feeders. Goats visited the floor-level feeder (36.4 ± 8.4 visits/goat) less than the head-level (79.4 ± 8.4 visits/goat) and elevated-level (74.8 ± 8.4 visits/goat) feeders. The number of displacements per minute of feeding time (physical removal of another goat from the feeding place) was greater at the elevated-level feeder (0.46 ± 0.06 displacements/min) compared with the floor-level feeder (0.23 ± 0.06 displacements/min) and tended to differ from the head-level feeder (0.27 ± 0.06 displacements/min). We conclude that goats eat more from an elevated feeder and compete more to access this feeder. Copyright © 2018 American Dairy Science Association. Published by Elsevier Inc. All rights reserved.
Freas, C A; Bingman, K; Ladage, L D; Pravosudov, V V
2013-01-01
Variation in environmental conditions associated with differential selection on spatial memory has been hypothesized to result in evolutionary changes in the morphology of the hippocampus, a brain region involved in spatial memory. At the same time, it is well known that the morphology of the hippocampus might also be directly affected by environmental conditions. Understanding the role of environment-based plasticity is therefore critical when investigating potential adaptive evolutionary changes in the hippocampus associated with environmental variation. We previously demonstrated large elevation-related variation in hippocampus morphology in mountain chickadees over an extremely small spatial scale. We hypothesized that this variation is related to differential selection pressures associated with differences in winter climate severity along an elevation gradient, which make different demands on spatial memory used for food cache retrieval. Here, we tested whether such variation is experience based, generated by potential differences in the environment, by comparing the hippocampus morphology of chickadees from different elevations maintained in a uniform captive environment in a laboratory with those sampled directly from the wild. In addition, we compared hippocampal neuron soma size in chickadees sampled directly from the wild with those maintained in laboratory conditions with restricted and unrestricted spatial memory use via manipulation of food-caching experiences to test whether memory use can affect neuron soma size. There were significant elevation-related differences in hippocampus volume and the total number of hippocampal neurons, but not in neuron soma size, in captive birds. Captive environmental conditions were associated with a large reduction in hippocampus volume and neuron soma size, but not in the total number of neurons or in neuron soma size in other telencephalic regions. Restriction of memory use while in laboratory conditions produced no significant effects on hippocampal neuron soma size. Overall our results showed that captivity has a strong effect on hippocampus volume, which could be due, at least partly, to a reduction in neuron soma size specifically in the hippocampus, but it did not override elevation-related differences in hippocampus volume or in the total number of hippocampal neurons. These data are consistent with the idea of the adaptive nature of the elevation-related differences associated with selection on spatial memory, while at the same time demonstrating additional environment-based plasticity in hippocampus volume, but not in neuron numbers. Our results, however, cannot rule out that the differences between elevations might still be driven by some developmental or early posthatching conditions/experiences. © 2013 S. Karger AG, Basel.
McGlone, John; Sapkota, Avi
2014-01-01
Simple Summary Transport is a routine practice in the modern swine industry. Loading the pigs into trailers can be a novel and stressful experience for the animals. This study compared behaviors and physiological variables during and after loading using a ramp or elevator to determine which method is the least stressful to the pigs. Loading pigs by ramp appears to cause more stress than loading by elevator. Abstract Transport is an inevitable process in the modern U.S. swine industry. The loading process is a novel and potentially stressful experience. This study uses behavior, heart rate and leukocyte counts to compare stress one hour before, during and after loading via ramp or elevator. Piglets were held in a home pen (control (CON)), walked up and down an aisle (handled (HAN)), or walked to a truck and loaded via elevator (ELE) or ramp (RAM). Sitting, feeding and blood parameters did not show a significant treatment by time effect (p > 0.05). Standing behavior did not differ between CON and HAN piglets nor between RAM and ELE piglets (p > 0.05); however, CON and HAN piglets stood more than RAM and ELE piglets during treatment (p < 0.05). After treatment, drinking behavior was increased in RAM piglets (p < 0.05). The heart rate of ELE piglets decreased 6.3% after treatment; whereas the heart rate of RAM piglets remained elevated 2.4% (p < 0.05). In terms of heart rate, loading by elevator appears to be less stressful than loading by ramp. PMID:26480323
Kumar, Sumit; Chaitanya, Bharatula S K; Ghatty, Sreenivas; Reddy, Attipalli R
2014-11-01
Jatropha (Jatropha curcas) is a non-edible oil producing plant which is being advocated as an alternative biofuel energy resource. Its ability to grow in diverse soil conditions and minimal requirements of essential agronomical inputs compared with other oilseed crops makes it viable for cost-effective advanced biofuel production. We designed a study to investigate the effects of elevated carbon dioxide concentration ([CO(2)]) (550 ppm) on the growth, reproductive development, source-sink relationships, fruit and seed yield of J. curcas. We report, for the first time that elevated CO(2) significantly influences reproductive characteristics of Jatropha and improve its fruit and seed yields. Net photosynthetic rate of Jatropha was 50% higher in plants grown in elevated CO(2) compared with field and ambient CO(2) -grown plants. The study also revealed that elevated CO(2) atmosphere significantly increased female to male flower ratio, above ground biomass and carbon sequestration potential in Jatropha (24 kg carbon per tree) after 1 year. Our data demonstrate that J. curcas was able to sustain enhanced rate of photosynthesis in elevated CO(2) conditions as it had sufficient sink strength to balance the increased biomass yields. Our study also elucidates that the economically important traits including fruit and seed yield in elevated CO(2) conditions were significantly high in J. curcas that holds great promise as a potential biofuel tree species for the future high CO(2) world. © 2014 Scandinavian Plant Physiology Society.
Ito, Takayasu; Fujimoto, Naoki; Ishikawa, Eiji; Dohi, Kaoru; Fujimoto, Mika; Murata, Tomohiro; Kiyohara, Michiyo; Takeuchi, Hideyuki; Koyabu, Sukenari; Nishimura, Hiroyuki; Takeuchi, Toshiaki; Ito, Masaaki
2018-03-27
Intradialytic hypertension (HTN), which is one of the poor prognostic markers in patients undergoing hemodialysis, may be associated with sympathetic overactivity. The L/N-type calcium channel blocker, cilnidipine, has been reported to suppress sympathetic nerves activity in vivo. Therefore, we hypothesized that cilnidipine could attenuate intradialytic systolic blood pressure (SBP) elevation. Fifty-one patients on chronic hemodialysis who had intradialytic-HTN (SBP elevation ≥10 mmHg during hemodialysis) and no fluid overload were prospectively randomized into two groups: control and cilnidipine groups. Cilnidipine group patients took cilnidipine (10 mg/day) for 12 weeks. The primary endpoint was the change in the intradialytic SBP elevation before and after the 12-week intervention. Before the intervention, no differences were observed in age, sex or pre-dialytic SBP (148.5 ± 12.9 vs. 148.3 ± 19.3 mmHg) between the two groups. Intradialytic SBP elevation was unchanged in the control group. Cilnidipine significantly lowered the post-dialytic SBP with an attenuation of the intradialytic SBP elevation from 12.0 ± 15.4 mmHg to 4.8 ± 10.1 mmHg. However, the observed difference in the intradialytic SBP elevation by cilnidipine did not reach statistical significance (group×time interaction effect p = 0.25). Cathecolamine levels were unaffected by the intervention in both groups. Cilnidipine lowers both the pre- and post-dialytic SBP and might attenuate intradialytic SBP elevation. Therefore, cilnidipine may be effective in lowering SBP during HD in patients with intradialytic-HTN.
Ball-Damerow, Joan E.; Oboyski, Peter T.; Resh, Vincent H.
2015-01-01
Abstract The recently completed Odonata database for California consists of specimen records from the major entomology collections of the state, large Odonata collections outside of the state, previous literature, historical and recent field surveys, and from enthusiast group observations. The database includes 32,025 total records and 19,000 unique records for 106 species of dragonflies and damselflies, with records spanning 1879–2013. Records have been geographically referenced using the point-radius method to assign coordinates and an uncertainty radius to specimen locations. In addition to describing techniques used in data acquisition, georeferencing, and quality control, we present assessments of the temporal, spatial, and taxonomic distribution of records. We use this information to identify biases in the data, and to determine changes in species prevalence, latitudinal ranges, and elevation ranges when comparing records before 1976 and after 1979. The average latitude of where records occurred increased by 78 km over these time periods. While average elevation did not change significantly, the average minimum elevation across species declined by 108 m. Odonata distribution may be generally shifting northwards as temperature warms and to lower minimum elevations in response to increased summer water availability in low-elevation agricultural regions. The unexpected decline in elevation may also be partially the result of bias in recent collections towards centers of human population, which tend to occur at lower elevations. This study emphasizes the need to address temporal, spatial, and taxonomic biases in museum and observational records in order to produce reliable conclusions from such data. PMID:25709531
Tiffan, K.F.; Haskell, C.A.; Kock, T.J.
2010-01-01
Chum salmon Oncorhynchus keta that spawn in main-stem habitats below Bonneville Dam on the Columbia River, USA, are periodically subjected to elevated discharges that may alter spawning behaviour. We investigated behavioural responses of spawning chum salmon to increased water velocities associated with experimental increases in tailwater elevation using acoustic telemetry and a dual-frequency identification sonar. Chum salmon primarily remained near their redds at base tailwater elevations (3.5 m above mean sea level), but displayed different movement and behavioural responses as elevations were increased to either 4.1 or 4.7m for 8-h periods. When velocities remained suitable (<0.8m s-1) during elevated-tailwater tests, female chum salmon remained near their redds but exhibited reduced digging activity as water velocities increased. However, when velocities exceeded 0.8m s-1, the females that remained on their redds exhibited increased swimming activity and digging virtually ceased. Female and male chum salmon that left their redds when velocities became unsuitable moved mean distances ranging from 32 to 58 m to occupy suitable velocities, but returned to their redds after tailwaters returned to base levels. Spawning events (i.e. egg deposition) were observed for five of nine pairs of chum salmon following tests indicating any disruptions to normal behaviour caused by elevated tailwaters were likely temporary. We believe a chum salmon's decision to either remain on, or leave, its redd during periods of unsuitably high water velocities reflects time invested in the redd and the associated energetic costs it is willing to incur. ?? 2009 John Wiley & Sons, Ltd.
2015-08-01
optimized space-time interpolation method. Tangible geospatial modeling system was further developed to support the analysis of changing elevation surfaces...Evolution Mapped by Terrestrial Laser Scanning, talk, AGU Fall 2012 *Hardin E, Mitas L, Mitasova H., Simulation of Wind -Blown Sand for...Geomorphological Applications: A Smoothed Particle Hydrodynamics Approach, GSA 2012 *Russ, E. Mitasova, H., Time series and space-time cube analyses on
In Situ Elevated Temperature Testing of Fly Ash Based Geopolymer Composites.
Vickers, Les; Pan, Zhu; Tao, Zhong; van Riessen, Arie
2016-06-03
In situ elevated temperature investigations using fly ash based geopolymers filled with alumina aggregate were undertaken. Compressive strength and short term creep tests were carried out to determine the onset temperature of viscous flow. Fire testing using the standard cellulose curve was performed. Applying a load to the specimen as the temperature increased reduced the temperature at which viscous flow occurred (compared to test methods with no applied stress). Compressive strength increased at the elevated temperature and is attributed to viscous flow and sintering forming a more compact microstructure. The addition of alumina aggregate and reduction of water content reduced the thermal conductivity. This led to the earlier onset and shorter dehydration plateau duration times. However, crack formation was reduced and is attributed to smaller thermal gradients across the fire test specimen.
Computation of times of sunrise, sunset, and twilight in or near mountainous terrain
Bill C. Ryan
1977-01-01
An electronic calculator with trigonometric functions can be used to compute times of sunrise, sunset, or twilight, or time of desired illumination at any location in mountainous terrain. The method is more convenient and versatile, and less cumbersome than using tables. Latitude, longitude, elevation, day of the year (1 to 366), and slope to the horizon at the...
Examining job tenure and lost-time claim rates in Ontario, Canada, over a 10-year period, 1999-2008.
Morassaei, Sara; Breslin, F Curtis; Shen, Min; Smith, Peter M
2013-03-01
We sought to examine the association between job tenure and lost-time claim rates over a 10-year period in Ontario, Canada. Data were obtained from workers' compensation records and labour force survey data from 1999 to 2008. Claim rates were calculated for gender, age, industry, occupation, year and job tenure group. A multivariate analysis and examination of effect modification were performed. Differences in injury event and source of injury were also examined by job tenure. Lost-time claim rates were significantly higher for workers with shorter job tenure, regardless of other factors. Claim rates for new workers differed by gender, age and industry, but remained relatively constant at an elevated rate over the observed time period. This study is the first to examine lost-time claim rates by job tenure over a time period during which overall claim rates generally declined. Claim rates did not show a convergence by job tenure. Findings highlight that new workers are still at elevated risk, and suggest the need for improved training, reducing exposures among new workers, promoting permanent employment, and monitoring work injury trends and risk factors.
Hermans, Maaike P J; Velders, Matthijs A; Smeekes, Martin; Drexhage, Olivier S; Hautvast, Raymond W M; Ytsma, Timon; Schalij, Martin J; Umans, Victor A W M
2017-08-04
Timely reperfusion with primary percutaneous coronary intervention (pPCI) in ST-segment elevation myocardial infarction (STEMI) patients is associated with superior clinical outcomes. Aiming to reduce ischaemic time, an innovative system for home-to-hospital (H2H) time monitoring was implemented, which enabled real-time evaluation of ischaemic time intervals, regular feedback and improvements in the logistic chain. The objective of this study was to assess the results after implementation of the H2H dashboard for monitoring and evaluation of ischaemic time in STEMI patients. Ischaemic time in STEMI patients transported by emergency medical services (EMS) and treated with pPCI in the Noordwest Ziekenhuis, Alkmaar before (2008-2009; n=495) and after the implementation of the H2H dashboard (2011-2014; n=441) was compared. Median time intervals were significantly shorter in the H2H group (door-to-balloon time 32 [IQR 25-43] vs. 40 [IQR 28-55] minutes, p-value <0.001, FMC-to-balloon time 62 [IQR 52-75] vs. 80 [IQR 67-103] minutes, p-value <0.001, and treatment delay 142 [IQR 103-221] vs. 159 [IQR 123-253] minutes, p-value <0.001). The H2H time dashboard was independently associated with shorter time delays. Real-time monitoring and feedback on time delay with the H2H dashboard improves the logistic chain in STEMI patients, resulting in shorter ischaemic time intervals.
Connecting Snowmelt Runoff Timing Changes to Watershed Characteristics in California
NASA Astrophysics Data System (ADS)
Stewart, I. T.; Peterson, D. H.
2008-12-01
Shifts in the timing of snowmelt runoff are an expected consequence of climatic changes and have been observed throughout western North America for the past several decades. While the snowmelt runoff has in general come earlier, the magnitude, and sometimes direction, of streamflow timing trends has varied throughout the region in a manner that is not explained by the differences in location or gauge elevation alone. The gauge-to-gauge differences in the observed streamflow timing trends, which have not been systematically explored, are investigated in this study by linking the hydrologic response of a stream to the physical characteristics of the watershed above the gauge. To this end, the very recent trends in streamflow timing measures (such as the timing of the start of the spring snowmelt pulse, the timing of the center of mass for flow, the annual flow, and the timing of the day when maximum flow occurs) for approximately 60 snowmelt-dominated gauges in California were analyzed in conjunction with a GIS-based data base of the watershed characteristics (such as elevation distribution, slope, aspect, and vegetation) through the 2008 runoff season. The improved knowledge of how a watershed has reacted to recent climatic changes can aid in the development of future adaptive strategies in managing water resources in California.
Talhelm, Alan F; Pregitzer, Kurt S; Kubiske, Mark E; Zak, Donald R; Campany, Courtney E; Burton, Andrew J; Dickson, Richard E; Hendrey, George R; Isebrands, J G; Lewin, Keith F; Nagy, John; Karnosky, David F
2014-08-01
Three young northern temperate forest communities in the north-central United States were exposed to factorial combinations of elevated carbon dioxide (CO2 ) and tropospheric ozone (O3 ) for 11 years. Here, we report results from an extensive sampling of plant biomass and soil conducted at the conclusion of the experiment that enabled us to estimate ecosystem carbon (C) content and cumulative net primary productivity (NPP). Elevated CO2 enhanced ecosystem C content by 11%, whereas elevated O3 decreased ecosystem C content by 9%. There was little variation in treatment effects on C content across communities and no meaningful interactions between CO2 and O3 . Treatment effects on ecosystem C content resulted primarily from changes in the near-surface mineral soil and tree C, particularly differences in woody tissues. Excluding the mineral soil, cumulative NPP was a strong predictor of ecosystem C content (r(2) = 0.96). Elevated CO2 enhanced cumulative NPP by 39%, a consequence of a 28% increase in canopy nitrogen (N) content (g N m(-2) ) and a 28% increase in N productivity (NPP/canopy N). In contrast, elevated O3 lowered NPP by 10% because of a 21% decrease in canopy N, but did not impact N productivity. Consequently, as the marginal impact of canopy N on NPP (∆NPP/∆N) decreased through time with further canopy development, the O3 effect on NPP dissipated. Within the mineral soil, there was less C in the top 0.1 m of soil under elevated O3 and less soil C from 0.1 to 0.2 m in depth under elevated CO2 . Overall, these results suggest that elevated CO2 may create a sustained increase in NPP, whereas the long-term effect of elevated O3 on NPP will be smaller than expected. However, changes in soil C are not well-understood and limit our ability to predict changes in ecosystem C content. © 2014 The Authors Global Change Biology Published by John Wiley & Sons Ltd.
Kotey, Stanley; Carrico, Ruth; Wiemken, Timothy Lee; Furmanek, Stephen; Bosson, Rahel; Nyantakyi, Florence; VanHeiden, Sarah; Mattingly, William; Zierold, Kristina M
2018-02-01
To examine elevated blood lead levels (EBLLs) in refugee children by postrelocation duration with control for several covariates. We assessed EBLLs (≥ 5µg/dL) between 2012 and 2016 of children younger than 15 years (n = 1950) by the duration of resettlement to health screening by using logistic regression, with control for potential confounders (gender, region of birth, age of housing, and intestinal infestation) in a cross-sectional study. Prevalence of EBLLs was 11.2%. Length of time from resettlement to health screening was inversely associated with EBLLs (tertile 2 unadjusted odds ratio [OR] = 0.79; 95% confidence interval [CI] = 0.56, 1.12; tertile 3 OR = 0.62; 95% CI = 0.42, 0.90; tertile 2 adjusted odds ratio [AOR] = 0.62; 95% CI = 0.39, 0.97; tertile 3 AOR = 0.57; 95% CI = 0.34, 0.93). There was a significant interaction between intestinal infestation and age of housing (P < .003), indicating significant risk in the joint exposure of intestinal infestation (a pica proxy) and age of house. Elevated blood lead levels were reduced with increasing length of time of resettlement in unadjusted and adjusted models. Improved housing, early education, and effective safe-house inspections may be necessary to address EBLLs in refugees.
A meta-analysis of responses of soil biota to global change.
Blankinship, Joseph C; Niklaus, Pascal A; Hungate, Bruce A
2011-03-01
Global environmental changes are expected to impact the abundance of plants and animals aboveground, but comparably little is known about the responses of belowground organisms. Using meta-analysis, we synthesized results from over 75 manipulative experiments in order to test for patterns in the effects of elevated CO(2), warming, and altered precipitation on the abundance of soil biota related to taxonomy, body size, feeding habits, ecosystem type, local climate, treatment magnitude and duration, and greenhouse CO(2) enrichment. We found that the positive effect size of elevated CO(2) on the abundance of soil biota diminished with time, whereas the negative effect size of warming and positive effect size of precipitation intensified with time. Trophic group, body size, and experimental approaches best explained the responses of soil biota to elevated CO(2), whereas local climate and ecosystem type best explained responses to warming and altered precipitation. The abundance of microflora and microfauna, and particularly detritivores, increased with elevated CO(2), indicative of microbial C limitation under ambient CO(2). However, the effects of CO(2) were smaller in field studies than in greenhouse studies and were not significant for higher trophic levels. Effects of warming did not depend on taxon or body size, but reduced abundances were more likely to occur at the colder and drier sites. Precipitation limited all taxa and trophic groups, particularly in forest ecosystems. Our meta-analysis suggests that the responses of soil biota to global change are predictable and unique for each global change factor.
Pulmonary biochemical effects of inhaled phosgene in rats.
Franch, S; Hatch, G E
1986-01-01
Three exposure regimens were used to study the time course of indicators of lung damage and recovery response to single or repeated exposures to phosgene (COCl2). Rats were sacrificed immediately or throughout a 38-d recovery period after inhalation of 1 ppm COCl2 for 4 h, at intervals during a 7-h exposure to 1 ppm phosgene, or at several time points throughout a 17-d exposure to 0.125 and 0.25 ppm COCl2 (4 h/d, 5 d/wk) and during a 21-d recovery period. Regimen 1 revealed significantly elevated lung wet weight, lung nonprotein sulfhydryl (NPSH) content, and glucose-6-phosphate dehydrogenase (G6PD) activity that stayed elevated for up to 14 d. A significant decrease in body weight and food intake was observed 1 d after exposure. Regimen 2 caused a slight depression in NPSH content but did not affect G6PD activity. Regimen 3 animals showed sustained elevations in lung wet weight, NPSH content, and G6PD activity after 7 d of exposure. No significant changes in these endpoints were observed for the 0.125 ppm COCl2 group. No consistent elevation in hydroxyproline content was seen at either exposure concentration. Light microscopic examination of lung tissue exposed to 0.25 ppm COCl2 for 17 d revealed moderate multifocal accumulation of mononuclear cells in the centriacinar region. In summary, exposure to COCl2 caused changes similar in most ways to those observed for other lower-respiratory-tract irritants.
Barnard, R J; Gardner, G W; Diaco, N V; Kattus, A A
1975-11-01
Near-maximal ECG stress testing and coronary artery disease risk factor analysis including blood pressure, serum cholesterol and smoking habits were conducted on a randomly selected group (N=90) of Los Angeles City Fire Fighters ranging in age from 40 to 59 yrs. The data obtained from the fire fighters were compared to data previously reported for a group of Los Angeles insurance underwriters of the same age range. Only 12% of the fire fighters had cholesterol values greater than 260 mg% while 18% of the insurance executives fell into this category. Only 2% of the fire fighters had blood pressure values greater than 160/90 mm Hg while 25% of the insurance executives were hypertensive. Thirty-two percent of the fire fighters were smokers at the time of testing as compared to 26% for the insurance executives. Only one fire fighter had all three risk factors elevated and only five had two risk factors elevated. Forty-seven of the fire fighters had no risk factors elevated. Ten percent of the fire fighters had ischemic stress tests as compared to 8% for the insurance executives. Of the nine fire fighters with ischemic stress tests one was hypertensive, one had elevated serum triglycerides, and three were smokers at the time of testing. Since the fire fighters are a medically-selected population with low risk factors for CHD, the observed incidence of ischemic stress tests is surprising and suggests that ischemic heart disease may be job associated.
Snyder, Alexander G.; Lacy, Jessica R.; Stevens, Andrew W.; Carlson, Emily M.
2016-06-10
The U.S. Geological Survey conducted a bathymetric survey in Little Holland Tract, a flooded agricultural tract, in the northern Sacramento-San Joaquin Delta (the “Delta”) during the summer of 2015. The new bathymetric data were combined with existing data to generate a digital elevation model (DEM) at 1-meter resolution. Little Holland Tract (LHT) was historically diked off for agricultural uses and has been tidally inundated since an accidental levee breach in 1983. Shallow tidal regions such as LHT have the potential to improve habitat quality in the Delta. The DEM of LHT was developed to support ongoing studies of habitat quality in the area and to provide a baseline for evaluating future geomorphic change. The new data comprise 138,407 linear meters of real-time-kinematic (RTK) Global Positioning System (GPS) elevation data, including both bathymetric data collected from personal watercraft and topographic elevations collected on foot at low tide. A benchmark (LHT15_b1) was established for geodetic control of the survey. Data quality was evaluated both by comparing results among surveying platforms, which showed systematic offsets of 1.6 centimeters (cm) or less, and by error propagation, which yielded a mean vertical uncertainty of 6.7 cm. Based on the DEM and time-series measurements of water depth, the mean tidal prism of LHT was determined to be 2,826,000 cubic meters. The bathymetric data and DEM are available at http://dx.doi.org/10.5066/F7RX9954.