1,678 research outputs found
Monitoring Winter Flow Conditions on the Ivishak River, Alaska
The Sagavanirktok River, a braided river on the Alaska North Slope, flows adjacent to the trans-Alaska pipeline for approximately 100 miles south of Prudhoe Bay. During an unprecedented flooding event in mid-May 2015, the pipeline was exposed in an area located approximately 20 miles south of Prudhoe Bay. The Ivishak River is a main tributary of the Sagavanirktok River, but little is known about its water flow characteristics and contribution to the Sagavanirktok River, especially in winter and during spring breakup. To gather this information, we installed water level sensors on two main tributaries of the Ivishak River (Upper Ivishak and Saviukviayak rivers), early in winter season 2016–2017, in open-water channels that showed promise as locations for long-term gauging stations. Our ultimate goal was to find a location for permanent deployment of water level sensors. By February, the first sites chosen were ice covered, so two additional sensors, one on each river, were deployed in different locations. Some of the sensors were lost (i.e., carried away by the current or buried under a thick layer of sediments). Water level data gathered from the sensors showed a maximum change of 1.07 m. Winter discharge measurements indicate a 44% reduction between February and April 2017. A summer discharge measurement shows a 430% increase from winter to summer
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Chromosome positioning is largely unaffected in lymphoblastoid cell lines containing emerin or A-type lamin mutations
Gene-poor human chromosomes are reproducibly found at the nuclear periphery in proliferating cells.
There are a number of inner nuclear envelope proteins that may have roles in chromosome location and
anchorage, e.g. emerin and A-type lamins. In the last decade, a number of diseases associated with tissue
degeneration and premature aging have been linked with mutations in lamin A or emerin. These are
termed laminopathies, withmutations in emerin causing Emery–Dreifuss muscular dystrophy. Despite highly
aberrant nuclear distributions of A-type lamins and emerin in lymphoblastoid cell lines derived from patients
with emerin or lamin A mutations, little or no change in chromosome location was detected
National Petroleum Reserve – Alaska (NPR-A) Watershed Hydrology
During a five-year period, which represents the entire project span, the research team performed
discharge measurements on seven gaging stations distributed on the National Petroleum Reserve-
Alaska (NPR-A), an area of approximately 23 million acres that extends from the north side of
the Brooks Range to the Arctic Ocean. Specifically, 225 discharge measurements were taken
during that period. In addition, records of air temperature and rainfall, as well as wind speed and
wind direction from stations that collected such data were analyzed. The air temperature data
indicate that the entire region followed a pronounced warming trend, ending with the 2010/2011
winter, which was the warmest winter recorded at the stations. Rainfall data suggest a trend in
increasing precipitation during the summer months from the coastal plain to the foothill area.
Unusually dry conditions were experienced over the entire area in 2007 and in 2011. The overall
highest mean wind speed was recorded in June at the two stations where wind data were
available; the lowest mean wind speed was recorded in December at one station and in March at
the other station. Wind roses indicate two main wind directions—roughly from the northeast and
southwest—with winds from the northeast predominant.List of Figures ................................................................................................................................ iii
List of Tables ................................................................................................................................. iv
Acknowledgments and Disclaimer ................................................................................................. v
Abstract .......................................................................................................................................... vi
CHAPTER 1 Introduction ........................................................................................................... 1
CHAPTER 2 Discharge Measurements ...................................................................................... 3
2.1 Fieldwork ......................................................................................................................... 3
2.2 Data Analysis ................................................................................................................... 7
CHAPTER 3 Meteorological Data ............................................................................................ 10
3.1 Methodology .................................................................................................................. 11
3.2 Results ............................................................................................................................ 11
3.2.1 Rainfall .................................................................................................................... 11
3.2.2 Air Temperature ...................................................................................................... 15
3.2.3 Wind ........................................................................................................................ 20
CHAPTER 4 Information Technology ...................................................................................... 28
4.1 Aquatic Informatics Aquarius Software ......................................................................... 28
4.2 Telemetry Data Retrieval ............................................................................................... 28
4.3 Near-Real-Time Data Delivery Online .......................................................................... 28
4.4 Information Technology Infrastructure .......................................................................... 30
References ..................................................................................................................................... 31
Appendices .................................................................................................................................... 3
Hydrological and Meteorological Observations on Seven Streams in the National Petroleum Reserve–Alaska (NPR–A)
This report summarizes the hydrological and meteorological data collected from 2003 to 2017 at
7 stations in the National Petroleum Reserve–Alaska. During an 8-year period, from May 2010
to December 2017, a research team from the University of Alaska Fairbanks, Water and
Environmental Research Center, and personnel from the Bureau of Land Management performed
351 discharge measurements and collected and analyzed data on air temperature, rainfall, wind
speed, and wind direction at stations distributed on a southwest–northeast transect from the
foothills of the Brooks Range to the Arctic Ocean. In general, the air temperature data indicate an
evident warming trend for the entire region. Rainfall data suggest a trend in increasing
precipitation during the summer months from the coastal plain to the foothills, though there are
some exceptions. The overall highest mean monthly wind speed was recorded in February; the
overall lowest mean monthly wind speed varied from station to station. Wind roses indicate two
main wind directions—approximately from the northeast and southwest—with winds from the
northeast predominant at the northern stations and winds from the southwest predominant at the
southern stations.List of Figures ................................................................................................................................ iii
List of Tables ................................................................................................................................. iv
Acknowledgments and Disclaimer ................................................................................................. v
Abstract .......................................................................................................................................... vi
CHAPTER 1 Introduction ........................................................................................................... 1
CHAPTER 2 Study Area ............................................................................................................. 2
CHAPTER 3 Discharge Measurements ...................................................................................... 3
3.1 Fieldwork ......................................................................................................................... 3
3.2 Data Processing ................................................................................................................ 9
CHAPTER 4 Meteorological Data ............................................................................................ 11
4.1 Methodology .................................................................................................................. 12
4.2 Results ............................................................................................................................ 12
4.2.1 Rainfall .................................................................................................................... 12
4.2.2 Air Temperature ...................................................................................................... 18
4.2.3 Wind ........................................................................................................................ 24
CHAPTER 5 Data Analysis ...................................................................................................... 37
CHAPTER 6 Conclusions and Recommendations.................................................................... 42
References ..................................................................................................................................... 43
Appendices .................................................................................................................................... 4
Performance of the Fully Digital FPGA-based Front-End Electronics for the GALILEO Array
In this work we present the architecture and results of a fully digital Front
End Electronics (FEE) read out system developed for the GALILEO array. The FEE
system, developed in collaboration with the Advanced Gamma Tracking Array
(AGATA) collaboration, is composed of three main blocks: preamplifiers,
digitizers and preprocessing electronics. The slow control system contains a
custom Linux driver, a dynamic library and a server implementing network
services. The digital processing of the data from the GALILEO germanium
detectors has demonstrated the capability to achieve an energy resolution of
1.53 per mil at an energy of 1.33 MeV.Comment: 5 pages, 6 figures, preprint version of IEEE Transactions on Nuclear
Science paper submitted for the 19th IEEE Real Time Conferenc
Constraint Force Equation Methodology for Modeling Multi-Body Stage Separation Dynamics
This paper discusses a generalized approach to the multi-body separation problems in a launch vehicle staging environment based on constraint force methodology and its implementation into the Program to Optimize Simulated Trajectories II (POST2), a widely used trajectory design and optimization tool. This development facilitates the inclusion of stage separation analysis into POST2 for seamless end-to-end simulations of launch vehicle trajectories, thus simplifying the overall implementation and providing a range of modeling and optimization capabilities that are standard features in POST2. Analysis and results are presented for two test cases that validate the constraint force equation methodology in a stand-alone mode and its implementation in POST2
Modeling Multibody Stage Separation Dynamics Using Constraint Force Equation Methodology
This paper discusses the application of the constraint force equation methodology and its implementation for multibody separation problems using three specially designed test cases. The first test case involves two rigid bodies connected by a fixed joint, the second case involves two rigid bodies connected with a universal joint, and the third test case is that of Mach 7 separation of the X-43A vehicle. For the first two cases, the solutions obtained using the constraint force equation method compare well with those obtained using industry- standard benchmark codes. For the X-43A case, the constraint force equation solutions show reasonable agreement with the flight-test data. Use of the constraint force equation method facilitates the analysis of stage separation in end-to-end simulations of launch vehicle trajectorie
Multidrug-resistant Pseudomonas aeruginosa producing PER-1 extended-spectrum serine-beta-lactamase and VIM-2 metallo-beta-lactamase.
[No abstract available]Europena Training and Mobility of Researchers Network on Metallo-beta-Lactamases (grant no. FMRX-CT98-0232
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