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A case study of boundary layer ventilation by convection and coastal processes
It is often assumed that ventilation of the atmospheric boundary layer is weak in the absence of fronts, but is this always true? In this paper we investigate the processes responsible for ventilation of the atmospheric boundary layer during a nonfrontal day that occurred on 9 May 2005 using the UK Met Office Unified Model. Pollution sources are represented by the constant emission of a passive tracer everywhere over land. The ventilation processes observed include shallow convection, turbulent mixing followed by large-scale ascent, a sea breeze circulation and coastal outflow. Vertical distributions of tracer are validated qualitatively with AMPEP (Aircraft Measurement of chemical Processing Export fluxes of Pollutants over the UK) CO aircraft measurements and are shown to agree impressively well. Budget calculations of tracers are performed in order to determine the relative importance of these ventilation processes. Coastal outflow and the sea breeze circulation were found to ventilate 26% of the boundary layer tracer by sunset of which 2% was above 2 km. A combination of coastal outflow, the sea breeze circulation, turbulent mixing and large-scale ascent ventilated 46% of the boundary layer tracer, of which 10% was above 2 km. Finally, coastal outflow, the sea breeze circulation, turbulent mixing, large-scale ascent and shallow convection together ventilated 52% of the tracer into the free troposphere, of which 26% was above 2 km. Hence this study shows that significant ventilation of the boundary layer can occur in the absence of fronts (and thus during high-pressure events). Turbulent mixing and convection processes can double the amount of pollution ventilated from the boundary layer
Antibiotic Stewardship Among Primary Care Providers In Mississippi
The World Health Organization states antimicrobial resistance is the ability of a microorganism to stop an antimicrobial from working which results in ineffective treatment and persistent infections. The Center for Disease Control and Prevention (CDC, 2017) reported that in the year 2015, 269.4 million antibiotic prescriptions were written in the outpatient setting, and approximately 30% of antibiotics written are unwarranted. Of those cases, most patients receive an antibiotic related to acute uncomplicated bronchitis, pharyngitis, or rhinosinusitis. The CDC reported that Americans spend nearly $11 billion yearly on antibiotics alone. However, up to 50% of all antibiotics prescribed are not indicated or optimally effective which eventually leads to resistance. Antibiotic resistant infections are associated with loss of productivity, poorer health outcomes, and greater healthcare costs. The CDC launched The Get Smart: Know When Antibiotics Work campaign in 2003 which aimed to direct appropriate antibiotic use (CDC, 2017). Within this campaign, the CDC provides outpatient regarding condition, epidemiology, diagnosis, and management for providers to follow for appropriate prescription. The purpose of this study was to determine if primary care providers in Mississippi are following the CDC Adult Treatment Recommendations for antibiotic use in the treatment of acute uncomplicated bronchitis, streptococcal pharyngitis, and acute unspecified pharyngitis (CDC, 2016). The researchers collected data in six rural clinics across Mississippi. This study consisted of a quantitative, retrospective chart review with descriptive statistics. A convenience sampling of 582 charts were obtained for the retrospective review. For data collection, the researchers used a data collection tool which included information related to age, gender, insurance, title o f provider, and diagnoses related to the current research and CDC Adult Treatment Recommendations. Prior to conducting the study, consent was obtained from the Institutional Review Board (IRB) at the Mississippi University for Women. After data collection, data were subjected to analyses using descriptive statistics including, but not limited to, frequency, distributions, and percentages. The findings suggested that primary care providers in Mississippi are not consistently following the CDC Adult Treatment Recommendations for acute pharyngitis and uncomplicated bronchitis
Vulnerability analysis of satellite-based synchronized smart grids monitoring systems
The large-scale deployment of wide-area monitoring systems could play a strategic role in supporting the evolution of traditional power systems toward smarter and self-healing grids. The correct operation of these synchronized monitoring systems requires a common and accurate timing reference usually provided by a satellite-based global positioning system. Although these satellites signals provide timing accuracy that easily exceeds the needs of the power industry, they are extremely vulnerable to radio frequency interference. Consequently, a comprehensive analysis aimed at identifying their potential vulnerabilities is of paramount importance for correct and safe wide-area monitoring system operation. Armed with such a vision, this article presents and discusses the results of an experimental analysis aimed at characterizing the vulnerability of global positioning system based wide-area monitoring systems to external interferences. The article outlines the potential strategies that could be adopted to protect global positioning system receivers from external cyber-attacks and proposes decentralized defense strategies based on self-organizing sensor networks aimed at assuring correct time synchronization in the presence of external attacks
Rapid Mapping of Zebrafish Mutations With SNPs and Oligonucleotide Microarrays
Large-scale genetic screens in zebrafish have identified thousands of mutations in hundreds of essential genes. The genetic mapping of these mutations is necessary to link DNA sequences to the gene functions defined by mutant phenotypes.Here, we report two advances that will accelerate the mapping of zebrafish mutations: (1) The construction of a first generation single nucleotide polymorphism (SNP) map of the zebrafish genome comprising 2035 SNPs and 178 small insertions/deletions, and (2) the development of a method for mapping mutations in which hundreds of SNPs can be scored in parallel with an oligonucleotide microarray.We have demonstrated the utility of the microarray technique in crosses with haploid and diploid embryos by mapping two known mutations to their previously identified locations.We have also used this approach to localize four previously unmapped mutations.We expect that mapping with SNPs and oligonucleotide microarrays will accelerate the molecular analysis of zebrafish mutations
Power-Based Droop Control in DC Microgrids Enabling Seamless Disconnection From Upstream Grids
This paper proposes a local power-based droop controller for distributed energy resource converters in dc microgrids that are connected to upstream grids by grid-interface converters. During normal operation, the grid-interface converter imposes the microgrid bus voltage, and the proposed controller allows power flow regulation at distributed energy resource converters\u2019 output. On the other hand, during abnormal operation of the grid-interface converter (e.g., due to faults in the upstream grid), the proposed controller allows bus voltage regulation by droop control. Notably, the controller can autonomously convert from power flow control to droop control, without any need of bus voltage variation detection schemes or communication with other microgrid components, which enables seamless transitions between these two modes of operation. Considering distributed energy resource converters employing the power-based droop control, the operation modes of a single converter and of the whole microgrid are defined and investigated herein. The controller design is also introduced. Furthermore, the power sharing performance of this control approach is analyzed and compared with that of classical droop control. The experimental results from a laboratory-scale dc microgrid prototype are reported to show the final performances of the proposed power-based droop control
Benefits of the Enhanced Recovery After Surgery (ERAS) Pathway With Quadratus Lumborum Blocks for Minimally Invasive Gynecologic Surgery Patients: A Retrospective Cohort Study
STUDY OBJECTIVE: This study aimed to determine the effect of the implementation of the Enhanced Recovery After Surgery (ERAS) protocol among patients receiving minimally invasive gynecologic surgery.
DESIGN AND SETTING: This retrospective cohort study was performed in a tertiary care hospital.
PATIENTS: A total of 328 females who underwent minimally invasive gynecologic surgeries requiring at least one overnight stay at Keck Hospital of University of Southern California (USC), California, USA, from 2016 to 2020 were included in this study.
INTERVENTIONS: The institutional ERAS protocol was implemented in late 2018. A total of 186 patients from 2016 to 2018 prior to the implementation were compared to 142 patients from 2018 to 2020 after the implementation. Intraoperatively, the ERAS group received a multimodal analgesic regimen (including bilateral quadratus lumborum (QL) blocks) and postoperative care geared toward a satisfactory, safe, and expeditious discharge.
MEASUREMENTS AND MAIN RESULTS: The two groups were similar in demographics, except for the shorter surgical time noted in the ERAS group. The median opioid use was significantly less among the ERAS patients compared with the non-ERAS patients on postoperative day 1 (7.5 vs. 14.3 mg; p
CONCLUSIONS: The ERAS pathway was associated with a reduction in opioid use postoperatively and a shorter length of hospital stay after minimally invasive gynecologic surgery. There was a more significant decrease in opioid use and hospital length of stay for patients with malignant diagnoses compared to patients with benign diagnoses. Further research can be done to fully delineate the effect of QL blocks in ERAS protocols
Does amyloid deposition produce a specific atrophic signature in cognitively normal subjects?☆
The objective of our study was to evaluate whether cognitively normal (CN) elderly participants showing elevated cortical beta-amyloid (Aβ) deposition have a consistent neuroanatomical signature of brain atrophy that may characterize preclinical Alzheimer's disease (AD). 115 CN participants who were Aβ-positive (CN +) by amyloid PET imaging; 115 CN participants who were Aβ-negative (CN −); and 88 Aβ-positive mild cognitive impairment or AD participants (MCI/AD +) were identified. Cortical thickness (FreeSurfer) and gray matter volume (SPM5) were measured for 28 regions-of-interest (ROIs) across the brain and compared across groups. ROIs that best discriminated CN − from CN + differed for FreeSurfer cortical thickness and SPM5 gray matter volume. Group-wise discrimination was poor with a high degree of uncertainty in terms of the rank ordering of ROIs. In contrast, both techniques showed strong and consistent findings comparing MCI/AD + to both CN − and CN + groups, with entorhinal cortex, middle and inferior temporal lobe, inferior parietal lobe, and hippocampus providing the best discrimination for both techniques. Concordance across techniques was higher for the CN − and CN + versus MCI/AD + comparisons, compared to the CN − versus CN + comparison. The weak and inconsistent nature of the findings across technique in this study cast doubt on the existence of a reliable neuroanatomical signature of preclinical AD in elderly PiB-positive CN participants
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