Analysis of Monthly, Seasonal, and Yearly Wind Flow Over the Ometepe Island in Lake Nicaragua

The health issues on the Ometepe Island in Lake Nicaragua are directly influenced by the open-pit fires inside of homes on the island and the particulates they produce. Understanding the prevailing wind patterns of the area would result in better advice for local homeowners on how to foster natural air flow through their homes and minimize the concentrations of trapped particulates. The purpose of this study is to identify prevailing wind patterns over the island in the monthly, seasonal, and yearly time frames. Due to the limited observations in the island area, the Weather Research and Forecasting model (WRF) was run at 1.33 km grid spacing, focusing on the area around the island to verify the small existing data set. Because of the verification, WRF simulations were used for an analysis of average wind direction and speed in the hopes of finding common, predictable wind patterns in the simulated data set. It is hypothesized that the most variation will occur between wind speed and direction in the wet and dry seasons, as the Intertropical Convergence Zone (ITCZ) will migrate southward into the area. With these useful climatologies, individuals in the local area should be able to create a mechanism to maximize awareness of how to properly foster natural cross-breeze ventilation

Regionally Enhanced Global Data Assimilation (REG DA): An Evaluation of the Limited Area Model Performance

Regionally Enhanced Global (REG) Data Assimilation (DA) is a method of global data assimilation in which high-resolution information from a single or multiple Limited Area Model (LAM) domains is blended with the global model information to create a regionally enhanced analysis of the global atmospheric state. This approach has been demonstrated to benefit both local and global model forecasts in idealized studies but has never been tested on operational numerical weather prediction models. This study investigates the limited area model forecast performance of an implementation of the REG DA approach on the operational 4D-Var data assimilation system, global model, and limited area model of the U.S. Navy. This implementation is called REG 4D-Var. The results of analysis-forecast experiments with the system show that the approach leads to small, but statistically significant overall forecast improvements and large and significant forecast improvements for Hurricane Sandy

Disruption of the maxi-K-caveolin-1 interaction alters current expression in human myometrial cells

<p>Abstract</p> <p>Background</p> <p>One determinant of the total K+ myometrial smooth muscle cell (MSMC) current is the large conductance, calcium- and voltage-activated potassium channel (maxi-K channel). This channel provides a repolarizing current in response to excitatory stimuli, most notably in response to increases in the levels of intracellular Ca2+, and blocking the channel by pharmacological means induces the depolarization of MSMCs and also enhances contraction strength. In MSMCs, maxi-K channels can reside in the caveolae, where they associate with the scaffolding protein caveolin-1 (cav-1). The aim of this study was to investigate the consequences of this interaction - more specifically, how disruption of the association between the maxi-K channel and cav-1 may influence the current expression and excitability of myometrial cells - with the aim of better understanding the mechanisms that underlie the regulation of normal and aberrant uterine function.</p> <p>Methods</p> <p>Myometrial biopsies were collected from women undergoing elective C-sections. From these samples, myometrial cells were isolated, cultured, infected with a virus containing either caveolin-1 (cav-1) siRNA or scrambled cav-1 siRNA, and finally subjected to patch-clamp analysis. Mutant caveolin-binding site maxi-K channel constructs were generated and transfected into mouse Ltk- fibroblasts. Channel activity, expression, association, and localization were examined by patch-clamping, Western blot, immunoprecipitation, and immunofluorescence, respectively.</p> <p>Results</p> <p>The caveolin-1 siRNA suppressed the total K+ current in human myometrial smooth muscle cells (hMSMC), as evident from comparison to the currents generated by both non-infected cells and cells infected with scrambled siRNA controls. The interaction between the maxi-K channel and caveolin depends on a region in the channel's C-terminal caveolin-binding site. Mutations of aromatic residues in this site (mutant F1012A, mutant Y1007A, F1012A and mutant Y1007A, F1012A, Y1015A) resulted in a decrease in K+ current compared to that produced by wild-type channels transfected into mouse Ltk- fibroblasts. However, mutation of all three aromatic amino acids (mutant Y1007A, F1012A, Y1015A) was necessary to disrupt the association between caveolin and the maxi-K channel, as visualized by immunofluorescence and immunoprecipitation.</p> <p>Conclusion</p> <p>Our results suggest that disruption of the caveolin-binding site interferes with the cav-1/maxi-K channel interaction, and that lack of the cav-1/maxi-K channel interaction in MSMCs attenuates the total K+ channel current of the cell.</p

“Sounding” Like Lake-Effect Snow: Evaluating the Thermodynamic and Synoptic Setup of Northwest Indiana Lake-Effect Events Using Local Profiles and Numerical Modeling

Lake-effect snow presents significant hazards for Northwest Indiana, which necessitates the need for accurate forecasts for these events. Recent radiosonde observations were taken routinely with radiosonde launches by Valparaiso University’s Aviation Team surrounding lake-effect events. From these soundings, thermodynamic environments are analyzed in conjunction with numerical simulations and official Green Bay soundings of 12 lake-effect precipitation events. This study will use the data from the sounding profiles and from numerical simulations to determine similarities and differences within the thermodynamic and synoptic environments surrounding these events. Through analysis of these pre-storm local environments, unique thresholds will be identified in environmental parameters associated with the setup and formation of lake-effect events over the southern Lake Michigan region. Creating a mean sounding for Northwest Indiana of these lake-effect setups would be optimal for aiding forecasts of similar future events. This analysis should allow observation of model biases and enhance the ability to predict lake-effect snow

Myometrial maxi-K channel β1 subunit modulation during pregnancy and after 17β-estradiol stimulation

AbstractMyometrial maxi-K channels are modulated by β subunits. We aimed to determine whether β subunits are modulated to affect uterine excitability during gestation. RNase protection analyses revealed that mouse β1 subunit transcripts are regulated during gestation with peak expression at day 14 of pregnancy. Immunohistochemical analysis indicates an increase of this subunit during gestation. Upregulation of the β1 transcript occurs with 4-day exposure to 17β-estradiol but not progesterone, and acute estradiol exposure has no effect on β1 transcript expression. These findings verify that β1 subunit transcript is regulated in mouse myometrium during gestation and estrogens may contribute to this increase

Sit still and pay attention: Using the Wii Balance-Board to detect lapses in concentration in children during psychophysical testing.

During psychophysical testing, a loss of concentration can cause observers to answer incorrectly, even when the stimulus is clearly perceptible. Such lapses limit the accuracy and speed of many psychophysical measurements. This study evaluates an automated technique for detecting lapses based on body movement (postural instability). Thirty-five children (8-11 years of age) and 34 adults performed a typical psychophysical task (orientation discrimination) while seated on a Wii Fit Balance Board: a gaming device that measures center of pressure (CoP). Incorrect responses on suprathreshold catch trials provided the "reference standard" measure of when lapses in concentration occurred. Children exhibited significantly greater variability in CoP on lapse trials, indicating that postural instability provides a feasible, real-time index of concentration. Limitations and potential applications of this method are discussed

Persistently active neurons in human medial frontal and medial temporal lobe support working memory

Persistent neural activity is a putative mechanism for the maintenance of working memories. Persistent activity relies on the activity of a distributed network of areas, but the differential contribution of each area remains unclear. We recorded single neurons in the human medial frontal cortex and medial temporal lobe while subjects held up to three items in memory. We found persistently active neurons in both areas. Persistent activity of hippocampal and amygdala neurons was stimulus-specific, formed stable attractors and was predictive of memory content. Medial frontal cortex persistent activity, on the other hand, was modulated by memory load and task set but was not stimulus-specific. Trial-by-trial variability in persistent activity in both areas was related to memory strength, because it predicted the speed and accuracy by which stimuli were remembered. This work reveals, in humans, direct evidence for a distributed network of persistently active neurons supporting working memory maintenance