956 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
Drivers’ experiences during floods: Investigating the psychological influences underpinning decisions to avoid driving through floodwater
A major risk factor for many flood-related drownings is driving through floodwater. We aimed to understand Australian drivers’ experiences and beliefs with respect to avoid driving through floodwater using the theory of planned behaviour as a framework. Study 1 (N = 23) used a qualitative design to gain an in-depth understanding of individuals’ experiences with driving through floodwater. Study 2 (N = 157) used a survey-based design to identify the factors related to this behaviour including knowledge, beliefs, and social-cognitive factors. In Study 1, drivers identified a range of advantages (e.g., didn't damage car), disadvantages (e.g., inconvenient, but not so terrible), barriers (e.g., urgency to reach destination), and facilitators (e.g., making plans and using existing plans) to avoiding driving through floodwater. Normative factors were also important influences on drivers’ decisions including normative expectancy, approval of significant others, and a moral obligation for the safety of others. In Study 2, participants were able to recall information about driving through floodwater (e.g., dangerous/risky) and its meaning (e.g., body of water over road). A range of experiences were described for avoiding driving through floodwater (e.g., took an alternative route). Across the studies, a range of behavioural, normative, and control beliefs were elicited. Finally, sex (women more likely), attitude, subjective norm, and perceived behavioural control significantly predicted intentions to avoid driving through floodwater, with the model explaining 55% of the variance. These findings can inform intervention targets and development of prevention strategies for effective behaviour change, saving lives otherwise lost to Australian waterways in flood
An evaluation of a video-based intervention targeting alcohol consumption during aquatic activities
Objective: Alcohol consumption and being male are drowning risk factors. Changing beliefs and intentions to undertake risky aquatic-related behaviours, such as consuming alcohol, is key to reducing loss of life and injury. We evaluated the impact of a video encouraging change in young males’ social cognitions and intentions to discourage their mates as well as their own alcohol consumption around the water.
Method: A three-wave non-controlled pre-test-post-test design was adopted. A convenience sample of Australian males aged 18–34 years (N = 97) who self-reported drinking alcohol and engaging in aquatic activities was recruited. Participants were surveyed at baseline (T1) regarding social cognition constructs and intentions, immediately after viewing the video (T2) and at a one-month follow-up (T3).
Results: Repeated measures ANOVAs revealed significant main effects of time on intentions, subjective norms, and attitudes regarding discouraging mates from drinking and swimming, but no significant main effects of time on perceived behavioural control or risk perceptions. The same patterns of effects were observed regarding drinking and swimming on males’ own behaviour.
Conclusions: The video has the potential to influence young males’ social cognitions regarding their mates’ and their own risky drinking behaviour around water in the short term, although sustained interventions are required. Messaging delivered on-site at popular aquatic locations in the lead-up to traditionally risky periods for alcohol-related drowning should be considered. Provision of strategies to combat social pressures among young males to act on their intentions to engage in drinking and swimming are needed
Inappropriate sinus tachycardia: focus on ivabradine
Inappropriate sinus tachycardia (IST) is an incompletely understood condition characterised by an elevation in heart rate (HR) accompanied by wide ranging symptoms, in the absence of an underlying physiological stimulus. The condition often takes a chronic course with significant adverse effects on quality of life. Currently there is no effective treatment for IST. Beta-blockers, generally considered the cornerstone of treatment, are often ineffective and poorly tolerated. Ivabradine is a novel sinus node If "funny current" inhibitor which reduces the HR. It has been approved for the treatment of beta-blocker refractory chronic systolic heart failure and chronic stable angina, but more recently shown promise in the treatment of IST. This review provides an overview of IST prevalence and mechanisms, followed by an examination of the evidence for the role and efficacy of ivabradine in the treatment of IST
Beliefs and attitudes of Australian learner drivers toward driving and avoiding driving through floodwater
Introduction: Driving through floodwater is a significant cause of flood-related injury and mortality, and opportunities exist to embed safe driving messages regarding floodwaters to novice drivers in graduated driver licensing schemes. To inform future educational efforts, we investigated the beliefs and attitudes of Australian learner drivers about driving and avoiding driving through floodwaters.
Methods: The study adopted a cross-sectional correlational design with measures drawn from the theory of planned behaviour and administered within an online survey. Phase 1 (N = 44 learner drivers) aimed to identify the core beliefs associated with driving through floodwater. Phase 2 (N = 250 learner drivers) tested these beliefs predicting willingness to drive through floodwater as well as the social psychological factors that predict learner drivers’ willingness to drive and avoid driving through floodwater using a pre-tested scenario. Analyses comprised descriptive statistics, linear regression, and structural equation models.
Results: Ten key beliefs were identified as predicting willingness to drive through floodwater. These included perceived advantages and disadvantages, perceived social approval from important others, and perceived facilitators and barriers regarding driving through floodwater in the presented scenario. Structural equation models of social cognition constructs of the theory of planned behaviour revealed attitude, subjective norm, and perceived behavioural control predicted both willingness to drive and avoid driving through floodwater. Past experience as a passenger also predicted these social cognition constructs, although this differed across models.
Discussion: Results highlight the importance of modelling safe driving behaviour for young passengers. The strong association between subjective norm and willingness to drive through floodwater further highlights the importance of those supervising learner drivers to establish expectations around avoiding driving through the floodwater if it is encountered on a driving route. Conclusion: Social cognition factors from the theory of planned behaviour predict willingness to drive and avoid driving though floodwater. Theory-based targets should be considered for the development of intervention programs for novice drivers, such as those holding learner licenses
Sagavanirktok River Spring Breakup Observations 2015
Alaska’s economy is strongly tied to oil production, with most of the petroleum coming from the
Prudhoe Bay oil fields. Deadhorse, the furthest north oil town on the Alaska North Slope,
provides support to the oil industry. The Dalton Highway is the only road that connects
Deadhorse with other cities in Interior Alaska. The road is heavily used to move supplies to and
from the oil fields.
In late March and early April 2015, the Dalton Highway near Deadhorse was affected by ice and
winter overflow from the Sagavanirktok River, which caused the road’s closure two times, for a
total of eleven days (four and seven days, respectively). In mid-May, the Sagavanirktok River at
several reaches flooded the Dalton from approximately milepost (MP) 394 to 414 (Deadhorse).
The magnitude of this event, the first recorded since the road was built in 1976, was such that the
Dalton was closed for nearly three weeks. During that time, a water station and several pressure
transducers were installed to track water level changes on the river. Discharge measurements
were performed, and water samples were collected to estimate suspended sediment
concentration.
Water levels changed from approximately 1 m near MP414 to around 3 m at the East Bank
station, located on the river’s east bank (about MP392). Discharge measurements ranged from
nearly 400 to 1560 m3/s, with the maximum measurement roughly coinciding with the peak.
Representative sediment sizes (D50) ranged from 10 to 14 microns. Suspended sediment
concentrations ranged from a few mg/L (clear water in early flooding stages) to approximately
4500 mg/L.
An analysis of cumulative runoff for two contiguous watersheds—the Putuligayuk and
Kuparuk—indicates that 2014 was a record-breaking year in both watersheds. Additionally, an
unseasonable spell of warm air temperatures was recorded during mid-February to early March.
While specific conditions responsible for this unprecedented flood are difficult to pinpoint,
runoff and the warm spell certainly contributed to the flood event.ABSTRACT ..................................................................................................................................... i
LIST OF FIGURES ....................................................................................................................... iii
LIST OF TABLES .......................................................................................................................... v
ACKNOWLEDGMENTS AND DISCLAIMER .......................................................................... vi
CONVERSION FACTORS, UNITS, WATER QUALITY UNITS, VERTICAL AND
HORIZONTAL DATUM, ABBREVIATIONS, AND SYMBOLS ............................................ vii
ABBREVIATIONS, ACRONYMS, AND SYMBOLS ................................................................ ix
1 INTRODUCTION ................................................................................................................... 1
2 STUDY AREA ........................................................................................................................ 5
3 METHODOLOGY AND EQUIPMENT ................................................................................ 9
3.1 Ice Elevations Prior to Breakup (GPS Surveys)............................................................. 10
3.2 X-Band SAR Analysis ................................................................................................... 11
3.3 Water Levels .................................................................................................................. 12
3.4 Acoustic Doppler Current Profiler ................................................................................. 14
3.5 Discharge Measurements ............................................................................................... 15
3.6 Suspended Sediments ..................................................................................................... 17
4 RESULTS .............................................................................................................................. 18
4.1 Air Temperature ............................................................................................................. 18
4.2 Annual Precipitation ....................................................................................................... 20
4.3 Cold Season Precipitation .............................................................................................. 22
4.4 Warm Season Precipitation ............................................................................................ 23
4.5 Surface Water Hydrology............................................................................................... 27
4.5.1 Ice Elevations .......................................................................................................... 28
4.5.2 X-Band SAR Analysis ............................................................................................ 31
4.5.3 Water Levels ........................................................................................................... 37
4.5.4 Discharge Measurements ........................................................................................ 43
4.5.5 Additional Field Observations ................................................................................ 49
4.5.6 Cumulative Volumetric Warm Season Runoff ....................................................... 59
4.5.7 Suspended Sediment ............................................................................................... 63
5 CONCLUSIONS ................................................................................................................... 66
6 REFERENCES ...................................................................................................................... 68
7 APPENDICES ....................................................................................................................... 72
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Sugar-sweetened beverage consumption, correlates and interventions among Australian Aboriginal and Torres Strait Islander communities: a scoping review protocol
Introduction: Aboriginal and Torres Strait Islander communities of Australia experience poorer health outcomes in the areas of overweight and obesity, diabetes and cardiovascular disease. Contributing to this burden of disease in the Australian community generally and in Aboriginal and Torres Strait Islander communities, is the consumption of sugar-sweetened beverages (SSBs). We have described a protocol for a review to systematically scope articles that document use of SSBs and interventions to reduce their consumption with Aboriginal and Torres Strait Islander people. These results will inform future work that investigates interventions aimed at reducing harm associated with SSB consumption. Methods and analysis: This scoping review draws on a methodology that uses a six-step approach to search databases including PubMed, SCOPUS, CINAHL, Informit (including Informit: Indigenous Peoples), Joanna Briggs Institute EBP Database and Mura, between January 1980 and February 2017. Two reviewers will be engaged to search for and screen studies independently, using formulated selection criteria, for inclusion in our review. We will include primary research studies, systematic reviews including meta-analysis or meta-synthesis, reports and unpublished grey literature. Results will be entered into a table identifying study details and characteristics, summarised using a Preferred Reporting Items for Systematic Reviews and Meta-Analysis chart and then critically analysed. Ethics and dissemination: This review will not require ethics committee review. Results will be disseminated at appropriate scientific meetings, as well as through the Aboriginal and Torres Strait Islander community.Jodie C Avery, Jacqueline A Bowden, Joanne Dono, Odette R Gibson, Aimee Brownbill, Wendy Keech, David Roder, Caroline L Mille
Hydro-sedimentological Monitoring and Analysis for Material Sites on the Sagavanirktok River
Researchers from the Water and Environmental Research Center at the Institute of Northern
Engineering, University of Alaska Fairbanks, are conducting a research project related to
sediment transport conditions along the Sagavanirktok River. This report presents tasks
conducted from summer 2015 to early winter 2016.
Four hydrometeorological stations were installed in early July 2015 on the west bank of the river.
The stations are spread out over a reach of approximately 90 miles along the Dalton Highway
(from MP 405, the northernmost location, to MP 318, the southernmost location). These stations
are equipped with pressure transducers and with air temperature, relative humidity, wind speed,
wind direction, barometric pressure, and turbidity sensors. Cameras were installed at each
station, and automatic water samplers were deployed during the open-water season. The stations
have a telemetry system that allows for transmitting data in near-real time.
Discharge measurements were performed three times: twice in July (early and late in the month),
and once in mid-September. Measured discharges were in the order of 100 m3/s, indicating that
measurements were performed during low flows. Suspended sediment concentrations ranged
from 2 mg/l (nearly clear water) to 625 mg/l. The average grain size for suspended sediment
from selected samples was 47.8 ÎĽm, which corresponds to silt. Vegetation was characterized at
27 plots near the stations. Measurements of basic water quality parameters, performed during
winter, indicated no potential issues at the sampled locations.
Dry and wet pits were excavated in the vicinity of each station. These trenches will be used to
estimate average bedload sediment transport during spring breakup 2016.
A change detection analysis of the period 1985–2007 along the area of interest revealed that
during the present study period, the river was relatively stable.ABSTRACT ..................................................................................................................................... i
LIST OF FIGURES ....................................................................................................................... iv
LIST OF TABLES ......................................................................................................................... vi
ACKNOWLEDGMENTS ............................................................................................................ vii
DISCLAIMER .............................................................................................................................. vii
CONVERSION FACTORS, UNITS, WATER QUALITY UNITS, VERTICAL AND
HORIZONTAL DATUM, ABBREVIATIONS, AND SYMBOLS ........................................... viii
ABBREVIATIONS, ACRONYMS, AND SYMBOLS ................................................................. x
1 INTRODUCTION AND STUDY AREA ............................................................................... 1
2 METHODOLOGY AND EQUIPMENT .............................................................................. 11
2.1 Pit Trenches .................................................................................................................... 12
2.2 Meteorology ................................................................................................................... 13
2.3 Water Level Measurements ............................................................................................ 13
2.4 Runoff............................................................................................................................. 14
2.5 Suspended Sediment ...................................................................................................... 15
2.6 Turbidity ......................................................................................................................... 15
2.7 Substrate and Floodplain Vegetation Survey ................................................................. 16
2.7.1 Site selection ........................................................................................................... 16
2.7.2 Quantifying substrate .............................................................................................. 16
2.7.3 Characterizing vegetation ....................................................................................... 17
3 RESULTS .............................................................................................................................. 19
3.1 Pit Trench Configuration ................................................................................................ 19
3.2 Meteorology ................................................................................................................... 27
3.3 Water Level Observations .............................................................................................. 27
3.4 Runoff............................................................................................................................. 31
3.4.1 Additional runoff observations ............................................................................... 31
3.5 Suspended Sediment ...................................................................................................... 32
3.6 Suspended Sediment Grain-Size Distribution ................................................................ 34
3.7 Turbidity ......................................................................................................................... 35
3.8 Water Quality ................................................................................................................. 37
4 ANALYSIS ........................................................................................................................... 39
4.1 Substrate and Vegetation ................................................................................................ 39
4.1.1 Substrate .................................................................................................................. 39
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4.1.2 Vegetation ............................................................................................................... 40
4.2 River Channel Stability .................................................................................................. 42
5 CONCLUSIONS ................................................................................................................... 56
6 REFERENCES ...................................................................................................................... 58
7 APPENDICES ....................................................................................................................... 6
Psychometric properties of the Stress Control Mindset Measure in University students from Australia and the UK.
Introduction: Beliefs about the consequences of stress, stress mindsets, are associated with health and performance outcomes under stress. This article reports the development and examination of the psychometric properties of a measure of stress mindset: The Stress Control Mindset Measure (SCMM). The measure is consistent with theory on mindsets about self-attributes and conceptualizes stress mindset as the extent to which individuals endorse beliefs that stress can be enhancing. Methods: The study adopted a correlational cross-sectional survey design in two student samples. Undergraduate students from an Australian university (Sample 1, N=218) and a UK university (Sample 2, N=214) completed the SCMM and measures of health and well being outcomes. Results: Confirmatory factor analyses supported a four-factor structure and strict measurement invariance across samples(ΔCFI <.01). Reliability, convergent validity, discriminant validity, and concurrent validity of the overall SCMM was supported in both samples. Incremental validity was supported for most outcomes, accounting for significantly more variance (between 2.2% and 5.9%) in health and wellbeing outcomes than an existing measure. Conclusions: Current data provide preliminary support for the SCMM as a reliable and valid measure with good psychometric properties and theoretically consistent relations with health outcomes under stress. Findings provide initial evidence supporting the potential utility of the SCMM in future research examining relations between stress mindsets and health and performance outcomes
Sagavanirktok River Spring Breakup Observations 2016
In 2015, spring breakup on the Sagavanirktok River near Deadhorse was characterized by high
flows that destroyed extensive sections of the Dalton Highway, closing the road for nearly 3
weeks. This unprecedented flood also damaged infrastructure that supports the trans-Alaska
pipeline, though the pipeline itself was not damaged. The Alaska Department of Transportation
and Public Facilities (ADOT&PF) and the Alyeska Pipeline Service Company made emergency
repairs to their respective infrastructure.
In December 2015, aufeis accumulation was observed by ADOT&PF personnel. In January
2016, a research team with the University of Alaska Fairbanks began monitoring and researching
the aufeis and local hydroclimatology. Project objectives included determining ice elevations,
identifying possible water sources, establishing surface meteorological conditions prior to
breakup, measuring hydrosedimentological conditions (discharge, water level, and suspended
sediment concentration) during breakup, and reviewing historical imagery of the aufeis feature.
Ice surface elevations were surveyed with Global Positioning System (GPS) techniques in late
February and again in mid-April, and measureable volume changes were calculated. However,
river ice thickness obtained from boreholes near Milepost 394 (MP394) in late February and
mid-April revealed no significant changes. It appears that flood mitigation efforts by ADOT&PF
in the area contributed to limited vertical growth in ice at the boreholes. End-of-winter snow
surveys throughout the watershed indicate normal or below normal snow water equivalents
(SWE 10 cm). An imagery analysis of the lower Sagavanirktok aufeis from late winter for the
past 17 years shows the presence of ice historically at the MP393–MP396 area.
Water levels and discharge were relatively low in 2016 compared with 2015. The mild breakup
in 2016 seems to have been due to temperatures dropping below freezing after the flow began.
Spring 2015 was characterized by warm temperatures throughout the basin during breakup,
which produced the high flows that destroyed sections of the Dalton Highway.
A comparison of water levels at the East Bank Station during 2015 and 2016 indicates that the
2015 maximum water level was approximately 1 m above the 2016 maximum water level.
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Maximum measured discharge in 2016 was approximately half of that measured in 2015 in the
lower Sagavanirktok River. Representative suspended sediment sizes (D50) ranged from 20 to 50
microns (medium to coarse silt).
An objective of this study was to determine the composition and possible sources of water in the
aufeis at the lower Sagavanirktok River. During the winter months and prior to breakup in 2016,
overflow water was collected, primarily near the location of the aufeis, but also at upriver
locations. Simultaneously possible contributing water sources were sampled between January
and July 2016, including snow, glacial meltwater, and river water. Geochemical analyses were
performed on all samples. It was found that the overflow water which forms the lower
Sagavanirktok aufeis is most similar (R2 = 0.997) to the water that forms the aufeis at the
Sagavanirktok River headwaters (Ivishak River), thought to be fed by relatively consistent
groundwater sources.ABSTRACT ..................................................................................................................................... i
LIST OF FIGURES ........................................................................................................................ v
LIST OF TABLES ......................................................................................................................... ix
ACKNOWLEDGMENTS AND DISCLAIMER ........................................................................... x
CONVERSION FACTORS, UNITS, WATER QUALITY UNITS, VERTICAL AND
HORIZONTAL DATUM, ABBREVIATIONS, AND SYMBOLS ............................................. xi
ABBREVIATIONS, ACRONYMS, AND SYMBOLS .............................................................. xiii
1 INTRODUCTION ................................................................................................................... 1
2 STUDY AREA ........................................................................................................................ 6
3 METHODOLOGY AND EQUIPMENT ................................................................................ 6
3.1 Aufeis Extent .................................................................................................................... 7
3.1.1 Field Methods ........................................................................................................... 7
3.1.2 Structure from Motion Imagery ................................................................................ 8
3.1.3 Imagery ..................................................................................................................... 8
3.2 Surface Meteorology ...................................................................................................... 10
3.3 Water Levels .................................................................................................................. 11
3.4 Discharge Measurements ............................................................................................... 13
3.5 Suspended Sediment ...................................................................................................... 16
3.6 Water Chemistry ............................................................................................................ 17
3.6.1 Sampling ................................................................................................................. 17
3.6.2 Trace Element Analysis .......................................................................................... 19
3.6.3 Data Analysis .......................................................................................................... 19
4 RESULTS .............................................................................................................................. 20
4.1 Air Temperature ............................................................................................................. 20
4.2 Wind Speed and Direction ............................................................................................. 29
4.3 Annual Precipitation ....................................................................................................... 30
4.4 Cold Season Precipitation .............................................................................................. 32
4.5 Warm Season Precipitation ............................................................................................ 36
4.6 Aufeis Extent .................................................................................................................. 40
4.6.1 Historical Aufeis at Franklin Bluffs ........................................................................ 40
4.6.2 Delineating Ice Surface Elevation with GPS and Aerial Imagery .......................... 46
4.6.3 Ice Boreholes .......................................................................................................... 55
iv
4.6.4 Ice Accumulation (SR50) ....................................................................................... 58
4.6.5 Ice Thickness and Volume ...................................................................................... 60
4.7 Surface Water Hydrology............................................................................................... 62
4.7.1 Sagavanirktok River at MP318 (DSS4) .................................................................. 67
4.7.2 Sagavanirktok River at Happy Valley (DSS3) ....................................................... 70
4.7.3 Sagavanirktok River Below the Ivishak River (DSS2)........................................... 73
4.7.4 Sagavanirktok River at East Bank (DSS5) Near Franklin Bluffs ........................... 76
4.7.5 Sagavanirktok River at MP405 (DSS1) West Channel .......................................... 85
4.7.6 Additional Field Observations ................................................................................ 86
4.8 Suspended Sediment ...................................................................................................... 87
4.9 Water Chemistry ............................................................................................................ 91
5 CONCLUSIONS ................................................................................................................... 96
6 REFERENCES ...................................................................................................................... 99
7 APPENDICES ..................................................................................................................... 10
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