5,206 research outputs found
Sedimentation in an artificial lake -Lake Matahina, Bay of Plenty
Lake Matahina, an 8 km long hydroelectric storage reservoir, is a small (2.5 km2), 50 m deep, warm monomictic, gorge-type lake whose internal circulation is controlled by the inflowing Rangitaiki River which drains a greywacke and acid volcanic catchment. Three major proximal to distal subenvironments are defined for the lake on the basis of surficial sediment character and dominant depositional process: (a) fluvial-glassy, quartzofeld-spathic, and lithic gravel-sand mixtures deposited from contact and saltation loads in less than 3 m depth; (b) (pro-)deltaic-quartzofeldspathic and glassy sand-silt mixtures deposited from graded and uniform suspension loads in 3-20 m depth; and (c) basinal-diatomaceous, argillaceous, and glassy silt-clay mixtures deposited from uniform and pelagic suspension loads in 20-50 m depth. The delta face has been prograding into the lake at a rate of 35-40 m/year and vertical accretion rates in pro-delta areas are 15-20 cm/year. Basinal deposits are fed mainly from river plume dispersion involving overflows, interflows, and underflows, and by pelagic settling, and sedimentation rates behind the dam have averaged about 2 cm/year. Occasional fine sand layers in muds of basinal cores attest to density currents or underflows generated during river flooding flowing the length of the lake along a sublacustrine channel marking the position of the now submerged channel of the Rangitaiki River
Implementation costs of a multi-component program to increase human papillomavirus (HPV) vaccination in a network of pediatric clinics
Introduction: HPV vaccination is both a clinically and cost-effective way to prevent HPV-related cancers. Increased focus on preventing HPV infection and HPV-related cancers has motivated development of strategies to increase adolescent vaccination rates. This analysis estimates the average cost associated with implementing programs aimed at increasing HPV vaccination from the perspective of the clinic decision makers. As providers and healthcare organizations consider vaccination initiatives, it is important for them to understand the costs associated with implementing these programs.
Methods: Healthcare provider assessment and feedback, reminders, and education; and parent education/reminder strategies were implemented in a large pediatric clinic network between October 2015 and February 2018 to improve HPV vaccination rates. A micro-costing method was used in 2018 to prospectively estimate program implementation costs with the clinic as the unit of analysis. A sensitivity analysis assessed the effects of variability in levels of participation.
Results: Assessment and feedback reports and provider education were implemented among 51 clinics at average per clinic cost of 368 respectively. Electronic vaccination reminders were delivered to providers and parents at a per clinic cost of 2,126 per clinic.
Conclusion: The four complimentary HPV evidence-based strategies were delivered at a total cost of 4,749 per clinic, including staff training and participant recruitment, reaching 155,000 HPV vaccine eligible adolescents
Deep subsurface drip irrigation using coal-bed sodic water: Part II. Geochemistry
Waters with low salinity and high sodium adsorption ratios (SARs) present a challenge to irrigation because they degrade soil structure and infiltration capacity. In the Powder River Basin of Wyoming, such low salinity (electrical conductivity, EC 2.1 mS cm−1) and high-SAR (54) waters are co-produced with coal-bed methane and some are used for subsurface drip irrigation (SDI). The SDI system studied mixes sulfuric acid with irrigation water and applies water year-round via drip tubing buried 92 cm deep. After six years of irrigation, SAR values between 0 and 30 cm depth (0.5–1.2) are only slightly increased over non-irrigated soils (0.1–0.5). Only 8–15% of added Na has accumulated above the drip tubing. Sodicity has increased in soil surrounding the drip tubing, and geochemical simulations show that two pathways can generate sodic conditions. In soil between 45-cm depth and the drip tubing, Na from the irrigation water accumulates as evapotranspiration concentrates solutes. SAR values \u3e12, measured by 1:1 water–soil extracts, are caused by concentration of solutes by factors up to 13. Low-EC (\u3c0.7 mS cm−1) is caused by rain and snowmelt flushing the soil and displacing ions in soil solution. Soil below the drip tubing experiences lower solute concentration factors (1–1.65) due to excess irrigation water and also contains relatively abundant native gypsum (2.4 ± 1.7 wt.%). Geochemical simulations show gypsum dissolution decreases soil-water SAR to \u3c7 and increases the EC to around 4.1 mS cm−1, thus limiting negative impacts from sodicity. With sustained irrigation, however, downward flow of excess irrigation water depletes gypsum, increasing soil-water SAR to \u3e14 and decreasing EC in soil water to 3.2 mS cm−1. Increased sodicity in the subsurface, rather than the surface, indicates that deep SDI can be a viable means of irrigating with sodic waters
Deep subsurface drip irrigation using coal-bed sodic water: Part II. Geochemistry
Waters with low salinity and high sodium adsorption ratios (SARs) present a challenge to irrigation because they degrade soil structure and infiltration capacity. In the Powder River Basin of Wyoming, such low salinity (electrical conductivity, EC 2.1 mS cm−1) and high-SAR (54) waters are co-produced with coal-bed methane and some are used for subsurface drip irrigation (SDI). The SDI system studied mixes sulfuric acid with irrigation water and applies water year-round via drip tubing buried 92 cm deep. After six years of irrigation, SAR values between 0 and 30 cm depth (0.5–1.2) are only slightly increased over non-irrigated soils (0.1–0.5). Only 8–15% of added Na has accumulated above the drip tubing. Sodicity has increased in soil surrounding the drip tubing, and geochemical simulations show that two pathways can generate sodic conditions. In soil between 45-cm depth and the drip tubing, Na from the irrigation water accumulates as evapotranspiration concentrates solutes. SAR values \u3e12, measured by 1:1 water–soil extracts, are caused by concentration of solutes by factors up to 13. Low-EC (\u3c0.7 mS cm−1) is caused by rain and snowmelt flushing the soil and displacing ions in soil solution. Soil below the drip tubing experiences lower solute concentration factors (1–1.65) due to excess irrigation water and also contains relatively abundant native gypsum (2.4 ± 1.7 wt.%). Geochemical simulations show gypsum dissolution decreases soil-water SAR to \u3c7 and increases the EC to around 4.1 mS cm−1, thus limiting negative impacts from sodicity. With sustained irrigation, however, downward flow of excess irrigation water depletes gypsum, increasing soil-water SAR to \u3e14 and decreasing EC in soil water to 3.2 mS cm−1. Increased sodicity in the subsurface, rather than the surface, indicates that deep SDI can be a viable means of irrigating with sodic waters
A molecular theory for two-photon and three-photon fluorescence polarization
In the analysis of molecular structure and local order in heterogeneous samples, multiphoton excitation of fluorescence affords chemically specific information and high-resolution imaging. This report presents the results of an investigation that secures a detailed theoretical representation of the fluorescence polarization produced by one-, two-, and three-photon excitations, with orientational averaging procedures being deployed to deliver the fully disordered limits. The equations determining multiphoton fluorescence response prove to be expressible in a relatively simple, generic form, and graphs exhibit the functional form of the multiphoton fluorescence polarization. Amongst other features, the results lead to the identification of a condition under which the fluorescence produced through the concerted absorption of any number of photons becomes completely unpolarized. It is also shown that the angular variation of fluorescence intensities is reliable indicator of orientational disorder
Benzylideneoxymorphone: A New Lead for Development of Bifunctional Mu/Delta Opioid Receptor Ligands
Opioid analgesic tolerance remains a considerable drawback to chronic pain management. The finding that concomitant administration of delta opioid receptor (DOR) antagonists attenuates the development of tolerance to mu opioid receptor (MOR) agonists has led to interest in producing bifunctional MOR agonist/DOR antagonist ligands. Herein, we present 7-benzylideneoxymorphone (6, UMB 246) displaying MOR partial agonist/DOR antagonist activity, representing a new lead for designing bifunctional MOR/DOR ligands
Jump-like unravelings for non-Markovian open quantum systems
Non-Markovian evolution of an open quantum system can be `unraveled' into
pure state trajectories generated by a non-Markovian stochastic (diffusive)
Schr\"odinger equation, as introduced by Di\'osi, Gisin, and Strunz. Recently
we have shown that such equations can be derived using the modal (hidden
variable) interpretation of quantum mechanics. In this paper we generalize this
theory to treat jump-like unravelings. To illustrate the jump-like behavior we
consider a simple system: A classically driven (at Rabi frequency )
two-level atom coupled linearly to a three mode optical bath, with a central
frequency equal to the frequency of the atom, , and the two side
bands have frequencies . In the large limit we
observed that the jump-like behavior is similar to that observed in this system
with a Markovian (broad band) bath. This is expected as in the Markovian limit
the fluorescence spectrum for a strongly driven two level atom takes the form
of a Mollow triplet. However the length of time for which the Markovian-like
behaviour persists depends upon {\em which} jump-like unraveling is used.Comment: 11 pages, 5 figure
Coastal oceanography and sedimentology in New Zealand, 1967-91.
This paper reviews research that has taken place on physical oceanography and sedimentology on New Zealand's estuaries and the inner shelf since c. 1967. It includes estuarine sedimentation, tidal inlets, beach morphodynamics, nearshore and inner shelf sedimentation, tides and coastal currents, numerical modelling, short-period waves, tsunamis, and storm surges. An extensive reference list covering both published and unpublished material is included. Formal teaching and research programmes dealing with coastal landforms and the processes that shape them were only introduced to New Zealand universities in 1964; the history of the New Zealand Journal of Marine and Freshwater Research parallels and chronicles the development of physical coastal science in New Zealand, most of which has been accomplished in last 25 years
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