scholarly journals A Poisson Cluster Stochastic Rainfall Generator That Accounts for the Interannual Variability of Rainfall Statistics: Validation at Various Geographic Locations across the United States

2014 ◽  
Vol 2014 ◽  
pp. 1-14 ◽  
Author(s):  
Dongkyun Kim ◽  
Jongho Kim ◽  
Yong-Sik Cho
Keyword(s):  
United States ◽  
Interannual Variability ◽  
Peak Flow ◽  
Traditional Approach ◽  
Extreme Rainfall ◽  
The United States ◽  
Watershed Response ◽  
Novel Approach ◽  
Rainfall Statistics ◽  
Poisson Cluster

A novel approach for a Poisson cluster stochastic rainfall generator was validated in its ability to reproduce important rainfall and watershed response characteristics at 104 locations in the United States. The suggested novel approach, The Hybrid Model (THM), as compared to the traditional Poisson cluster rainfall modeling approaches, has an additional capability to account for the interannual variability of rainfall statistics. THM and a traditional approach of Poisson cluster rainfall model (modified Bartlett-Lewis rectangular pulse model) were compared in their ability to reproduce the characteristics of extreme rainfall and watershed response variables such as runoff and peak flow. The results of the comparison indicate that THM generally outperforms the traditional approach in reproducing the distributions of peak rainfall, peak flow, and runoff volume. In addition, THM significantly outperformed the traditional approach in reproducing extreme rainfall by 2.3% to 66% and extreme flow values by 32% to 71%.

scholarly journals Orexin receptor antagonists reverse aberrant dopamine neuron activity and related behaviors in a rodent model of stress-induced psychosis

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Hannah B. Elam ◽  
Stephanie M. Perez ◽  
Jennifer J. Donegan ◽  
Daniel J. Lodge
Keyword(s):  
United States ◽  
Sensorimotor Gating ◽  
The United States ◽  
Dopamine Neuron ◽  
Neuron Activity ◽  
Sprague Dawley ◽  
Post Traumatic Stress ◽  
Neuron Population ◽  
Population Activity ◽  
Novel Approach

AbstractPost-traumatic stress disorder (PTSD) is a prevalent condition affecting approximately 8% of the United States population and 20% of United States combat veterans. In addition to core symptoms of the disorder, up to 64% of individuals diagnosed with PTSD experience comorbid psychosis. Previous research has demonstrated a positive correlation between symptoms of psychosis and increases in dopamine transmission. We have recently demonstrated projections from the paraventricular nucleus of the thalamus (PVT) to the nucleus accumbens (NAc) can regulate dopamine neuron activity in the ventral tegmental area (VTA). Specifically, inactivation of the PVT leads to a reversal of aberrant dopamine system function and psychosis-like behavior. The PVT receives dense innervation from orexin containing neurons, therefore, targeting orexin receptors may be a novel approach to restore dopamine neuron activity and alleviate PTSD-associated psychosis. In this study, we induced stress-related pathophysiology in male Sprague Dawley rats using an inescapable foot-shock procedure. We observed a significant increase in VTA dopamine neuron population activity, deficits in sensorimotor gating, and hyperresponsivity to psychomotor stimulants. Administration of selective orexin 1 receptor (OX1R) and orexin 2 receptor (OX2R) antagonists (SB334867 and EMPA, respectively) or the FDA-approved, dual-orexin receptor antagonist, Suvorexant, were found to reverse stress-induced increases in dopamine neuron population activity. However, only Suvorexant and SB334867 were able to reverse deficits in behavioral corelates of psychosis. These results suggest that the orexin system may be a novel pharmacological target for the treatment of comorbid psychosis related to PTSD.

scholarly journals A Climatology of 500-hPa Closed Lows in the Northeastern Pacific Ocean, 1948–2011

2014 ◽  
Vol 53 (6) ◽  
pp. 1578-1592 ◽  
Author(s):  
Nina S. Oakley ◽  
Kelly T. Redmond
Keyword(s):  
United States ◽  
Pacific Ocean ◽  
Interannual Variability ◽  
West Coast ◽  
The United States ◽  
Western United States ◽  
The West ◽  
Reanalysis Dataset ◽  
The Pacific ◽  
Northeastern Pacific

AbstractThe northeastern Pacific Ocean is a preferential location for the formation of closed low pressure systems. These slow-moving, quasi-barotropic systems influence vertical stability and sustain a moist environment, giving them the potential to produce or affect sustained precipitation episodes along the west coast of the United States. They can remain motionless or change direction and speed more than once and thus often pose difficult forecast challenges. This study creates an objective climatological description of 500-hPa closed lows to assess their impacts on precipitation in the western United States and to explore interannual variability and preferred tracks. Geopotential height at 500 hPa from the NCEP–NCAR global reanalysis dataset was used at 6-h and 2.5° × 2.5° resolution for the period 1948–2011. Closed lows displayed seasonality and preferential durations. Time series for seasonal and annual event counts were found to exhibit strong interannual variability. Composites of the tracks of landfalling closed lows revealed preferential tracks as the features move inland over the western United States. Correlations of seasonal event totals for closed lows with ENSO indices, the Pacific decadal oscillation (PDO), and the Pacific–North American (PNA) pattern suggested an above-average number of events during the warm phase of ENSO and positive PDO and PNA phases. Precipitation at 30 U.S. Cooperative Observer stations was attributed to closed-low events, suggesting 20%–60% of annual precipitation along the West Coast may be associated with closed lows.

Graft for Immediate use as First Stage of a Native Fistula

2009 ◽  
Vol 10 (3) ◽  
pp. 203-206 ◽  
Author(s):  
Earl Schuman
Keyword(s):  
United States ◽  
Graft Failure ◽  
The United States ◽  
Morbidity And Mortality ◽  
Dialysis Access ◽  
New Paradigm ◽  
Novel Approach ◽  
Native Fistula ◽  
Fistula Maturation

The majority of patients in the United States begin hemodialysis with a catheter. Many have immature or inadequate fistulae. At 90 days 77% of these patients are still using a catheter or a graft. The morbidity and mortality from prolonged catheter use have been well delineated. Although most of us adhere to the DOQI and Fistula First tenets, a fistula at all costs can seem counterproductive. A new paradigm is needed. The techniques described in this paper offer a novel approach to circumvent the problems of increasing catheter use and long fistula maturation times. The graft for immediate use is placed in the forearm and allows the proximal vessels to mature while providing dialysis access without a catheter. When these vessels meet maturation guidelines, or when surveillance indicates impending graft failure, a native fistula can be constructed and used in a 2–3 week period. This approach minimizes or circumvents catheter use altogether.

Interannual variability of crop residue potential in the north central region of the United States

2013 ◽  
Vol 49 ◽  
pp. 231-238 ◽  
Author(s):  
Rajesh Chintala ◽  
Michael C. Wimberly ◽  
Gemechis D. Djira ◽  
Mirela G. Tulbure
Keyword(s):  
United States ◽  
Interannual Variability ◽  
Central Region ◽  
Crop Residue ◽  
The United States ◽  
North Central Region ◽  
North Central ◽  
The North

scholarly journals Therapeutic Cocktail Approach for Treatment of Hyperhomocysteinemia in Alzheimer’s Disease

Cell Medicine ◽  
2018 ◽  
Vol 10 ◽  
pp. 215517901772228 ◽  
Author(s):  
Michael Leon ◽  
Darrell Sawmiller ◽  
R. Douglas Shytle ◽  
Jun Tan
Keyword(s):  
United States ◽  
Alzheimer’S Disease ◽  
Alzheimer's Disease ◽  
Risk Factor ◽  
The United States ◽  
Total Plasma ◽  
Common Cause ◽  
Total Cost ◽  
Novel Approach ◽  
Cocktail Approach

In the United States, Alzheimer's disease (AD) is the most common cause of dementia, accompanied by substantial economic and emotional costs. During 2015, more than 15 million family members who provided care to AD patients had an estimated total cost of 221 billion dollars. Recent studies have shown that elevated total plasma levels of homocysteine (tHcy), a condition known as hyperhomocysteinemia (HHcy), is a risk factor for AD. HHcy is associated with cognitive decline, brain atrophy, and dementia; enhances the vulnerability of neurons to oxidative injury; and damages the blood–brain barrier. Many therapeutic supplements containing vitamin B12 and folate have been studied to help decrease tHcy to a certain degree. However, a therapeutic cocktail approach with 5-methyltetrahydrofolate, methyl B12, betaine, and N-acetylcysteine (NAC) have not been studied. This novel approach may help target multiple pathways simultaneously to decrease tHcy and its toxicity substantially.

scholarly journals Comparing the Borich model with the Ranked Discrepancy Model for competency assessment: A novel approach

2021 ◽  
Vol 2 (3) ◽  
pp. 96-111
Author(s):  
Lendel Narine ◽  
Amy Harder
Keyword(s):  
United States ◽  
Online Survey ◽  
The United States ◽  
Training Needs ◽  
Competency Assessment ◽  
Land Grant University ◽  
Modern Times ◽  
Discrepancy Model ◽  
Novel Approach ◽  
High Level

In 1980, Borich presented a new model that allowed errors in an individual’s judgment of self-proficiency to be offset by considering the perception of a group. The model relied upon the calculation of means for competency items measured with ordinal scales, an approach subject to debate in modern times. The purpose of our study was to explore the use of a novel approach we developed, the Ranked Discrepancy Model (RDM), as an alternative method to the Borich model for determining training needs. Data obtained from an online survey of extension professionals employed by a land-grant university in the United States was used to compare the training needs identified by applying the Borich model with those identified by applying the RDM. A very strong and statistically significant correlation existed between the scores derived from using both models, demonstrating a high level of consistency between models. Researchers conducting competency research should consider adopting the RDM given its suitability for delivering results that closely resemble findings from the Borich model while providing improved rigor in methods and increased detail about training needs.

scholarly journals Taking the hydro out of hydrofracturing: Application of ultra-light weight proppants to cryogenic liquid nitrogen as a fracturing fluid

2018 ◽  
Vol 1 ◽  
pp. 57
Author(s):  
Amna Ahmed ◽  
Teresa Zhu ◽  
Amna Majeed
Keyword(s):  
United States ◽  
Liquid Nitrogen ◽  
The United States ◽  
Cryogenic Liquid ◽  
Gas Extraction ◽  
Light Weight ◽  
Stress Tests ◽  
Fracturing Fluids ◽  
Novel Approach ◽  
Waterless Fracturing

In the last decade, hydraulic fracturing has rapidly gained popularity worldwide, emerging as the leading method of natural gas extraction in the United States. However, the practice remains controversial due to its contribution to greenhouse gas emissions and the contamination of freshwater used in fracturing fluids. Although waterless fracturing fluids have been developed, including those using N2, CO2, oil, and alcohol, their application has been limited largely due to reduced fracturing power. Recent research has demonstrated that cryogenic nitrogen may prove a viable alternative, if this issue is properly addressed. Addition of durable, lightweight proppants is one way to increase fracturing power. This study aims to investigate the effect of proppant addition on the fracturing capabilities of cryogenic nitrogen. Three ultra-lightweight proppants will be combined with liquid nitrogen and fracturing power will be measured using triaxial stress tests. This novel approach has not yet been explored and will open more avenues of research into sustainable and efficient fracturing using  cryogenic nitrogen.

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