bluuebunny/crossref_metadata_2025_split huggingface dataset:
Point‐of‐Care Ultrasonography (POCUS) in a Community Emergency Department: An Analysis of Decision Making and Cost Savings Associated With POCUS
Authors: Van Schaik Graham W. W. , Van Schaik Katherine D. , Murphy Michael C. 
Published: December 2018

ObjectivesPoint‐of‐care ultrasonography (POCUS) is an increasingly integral part of emergency medicine. This study investigated community emergency department physicians’ choices regarding ultrasonography as a branch point in clinical decision making.MethodsDuring shifts covering all days of the week and all time‐spans over a 3‐month period, emergency department physicians were interviewed whenever POCUS was used. Questions focused on the role of POCUS in clinical management and on tests avoided because of ultrasonography use. Cost savings attributable to POCUS were calculated using Center for Medicare and Medicaid Services and FairHealth data. Anonymization of data precluded follow‐up testing to account for misdiagnosis.ResultsOn average, POCUS use eliminated $1134.31 of additional testing for privately insured patients, $2826.31 for out‐of‐network or uninsured patients, and $181.63 for Center for Medicare and Medicaid Services patients. Differences were significant when the total cost of eliminated additional testing was compared to a baseline of no savings (p < .001). Aggregate cost savings remained significant when analyses were broadened to include POCUS encounters that did not yield changes in management (p < .001).ConclusionsWhen physicians’ clinical expertise suggests that POCUS may be indicated, its use results in significant cost savings, even in encounters in which management is not directly impacted. POCUS, when incorporated earlier and more frequently into community hospital emergency medicine diagnostic protocols, can lower direct and indirect costs associated with diagnostic workups. Community emergency departments, in particular, would benefit from additional investigation informing specific guidelines for the integration of POCUS into clinical management and the role that this has in cost savings.
Cerebral Artery Vasospasm Detection Using Transcranial Doppler Signal Analysis
Authors: Elzaafarany Khaled , Aly Moustafa H. , Kumar Gyanendra , Nakhmani Arie 
Published: December 2018

ObjectivesSilent cerebral artery vasospasm in aneurysmal subarachnoid hemorrhage causes serious complications such as cerebral ischemia and death. A transcranial Doppler (TCD) ultrasound system is a noninvasive device that can effectively detect cerebral artery vasospasm as soon as it sets in, even before and in the absence of clinical deterioration. Continuous or even daily TCD monitoring is challenging because of the operator expertise and certification required in the form of a trained sonographer and interpretive experience required in the form of an additionally trained and certified physician to perform these studies. This barrier exists because of a lack of automation for detection (without human intervention) of cerebral artery vasospasm using TCD ultrasound. To overcome this barrier, we present an algorithm that automates detection of cerebral artery vasospasm.MethodsWe extracted features such as the energy, energy entropy, zero‐crossing rate, spectral centroid, spectral speed, spectral entropy, spectral flux, spectral roll‐off, harmonic ratio, chroma, and Mel frequency cepstral coefficients for signal classification. Then we applied principal component analysis to reduce the data dimensionality.ResultsAll of the chosen features were used for training a decision‐tree classifier. The algorithm had high accuracy for cerebral artery vasospasm detection, with overall sensitivity of 87.5% and specificity of 89.74%.ConclusionsThe algorithm has the potential for development into a continuous cerebral artery vasospasm monitor.
Occupancy of freshwater turtles across a gradient of altered landscapes
Authors: Buchanan Scott W. , Buffum Bill , Puggioni Gavino , Karraker Nancy E. 
Published: December 2018

ABSTRACTTurtles are one of the most threatened groups of vertebrates worldwide. In the northeastern United States, a legacy of centuries of dramatic landscape alteration has affected freshwater turtle populations, but the relationships between the current landscape and distributions and abundances of freshwater turtles remain poorly understood. We used a stratified random approach to select 88 small, isolated wetlands across a gradient of forest cover throughout Rhode Island, USA, and systematically sampled freshwater turtles in these wetlands. We report estimates of relative abundance and used a canonical correspondence analysis to investigate relationships between species relative abundance and environmental covariates. We also investigated which environmental covariates affect the occurrence and detection probabilities of each species. Eastern painted turtles (Chrysemys picta picta) and common snapping turtles (Chelydra serpentina) were widespread (occurring in 83% and 63% of wetlands, respectively) and relatively abundant. Spotted turtles (Clemmys guttata) were far less common, occurring in 8% of wetlands, and exhibited a positive association with shallow wetlands surrounded by forest. Non‐native red‐eared sliders (Trachemys scripta elegans) occurred in 10% of wetlands and exhibited a positive association with road density, likely reflecting a positive relationship between slider occurrence and human population density. Identifying landscape‐scale habitat features that are associated with the occurrence of sensitive species can improve the ability of biologists to identify and protect turtle populations. © 2018 The Wildlife Society.
Comparison of endoscopic and microscopic ear surgery in pediatric patients: A meta‐analysis
Authors: Han Sang‐Yoon , Lee Doh Young , Chung Juyong , Kim Young Ho 
Published: December 2018

ObjectivesRecently, the endoscope has been increasingly introduced for middle‐ear surgery. To evaluate the postoperative outcomes of endoscopic ear surgery (EES) in pediatric patients, we did a qualitative analysis with a systematic review and quantitative analysis with meta‐analysis of available literature.MethodsStudies reporting the comparative surgical outcomes of EES in pediatric patients were systematically reviewed by searching the MEDLINE, PubMed, and Embase databases from database inception through 2017. The selected articles included clinical studies conducted with at least 30 subjects and at least one postoperative parameter, including residual or recurrent cholesteatoma and graft success in tympanoplasty. Two investigators independently reviewed all studies and extracted the data using a standardized form. A meta‐analysis was performed using a random‐effects model and qualitative review was performed on the smaller studies.ResultsTen studies were identified as appropriate for quantitative meta‐analysis and 19 studies for qualitative analysis. In the meta‐analysis, residual or recurrence rate of cholesteatoma was significantly lower in the EES group than in the microscopic ear surgery (MES) group (odds ratio [OR]: 0.56, 95% confidence interval [CI]: 0.38‐0.84, P = .005). The graft success rate of tympanoplasty was not statistically different between EES and MES groups (OR: 0.72, 95% CI: 0.41‐1.26, P = .249). In the qualitative analysis, most of the studies reported similar audiological outcomes after tympanoplasty and success rate of cholesteatoma removal between the two groups.ConclusionsIt appears that EES reduces the risk of residual cholesteatoma in children and that the success of perforation closure is equivalent to MES.Laryngoscope, 129:1444–1452, 2019
Efficacy of tranexamic acid on operative bleeding in endoscopic sinus surgery: A meta‐analysis and systematic review
Authors: Kim Do Hyun , Kim Subin , Kang Haram , Jin Ho Jun , Hwang Se Hwan 
Published: December 2018

ObjectivesTranexamic acid might help control bleeding during surgery because of antifibrinolytic characteristics. We aimed to evaluate the effectiveness of systemic tranexamic acid compared to control in blood loss, operative time, and surgical field and incidence of postoperative emesis and thromboembolism in endoscopic sinus surgery.MethodsTwo authors independently searched six databases (PubMed, SCOPUS, Embase, the Web of Science, Google Scholar, and the Cochrane database) from their inception to July 2018. The included studies compared perioperative tranexamic acid administration (treatment group) with a placebo, and the outcomes of interest were intraoperative morbidities, including surgical time, operative bleeding, and hypotension; postoperative morbidities such as nausea and vomiting; and coagulation profiles.ResultsSeven studies comprising 562 participants were reviewed in this study. Operative time (standardized mean difference (SMD) = −0.60; 95% confidence interval (CI)[−0.93, −0.29]) and intraoperative blood loss (SMD = −0.66; 95% CI [−0.86, −0.46]) were statistically lower in the treatment group than placebo group; and the quality of the surgical field (SMD = −0.80; 95% CI [−1.12; −0.48]) and surgeon satisfaction (SMD = 1.74; 95% CI [1.36; 2.13]) were statistically higher in the treatment group than the placebo group. By contrast, there were no significant differences in the hemodynamic (SMD = 0.08; 95% CI [−0.20; 0.37]) and coagulation profiles (SMD = −0.18; 95% CI [−0.42, 0.07]) of the two groups. Additionally, tranexamic acid had no significant effect on emetic or thrombotic events compared to placebo.ConclusionThis meta‐analysis showed that the systemic administration of tranexamic acid could decrease operative time and blood loss intraoperatively, increasing the satisfaction of surgeons. It did not provoke intraoperative hemodynamic instability, postoperative emetic events, or coagulation profile abnormality. Only a small number of studies were enrolled, so further trials are needed to confirm the results of this study. Laryngoscope, 129:800–807, 2019
Septal fractures predict poor outcomes after closed nasal reduction: Retrospective review and survey
Authors: Arnold Mark A. , Yanik Susan C. , Suryadevara Amar C. 
Published: December 2018

Objectives/HypothesisTo determine outcomes of patients with displaced nasal bone fractures after closed nasal reduction (CNR).Study DesignRetrospective patient review.MethodsReview of all patients presenting to the emergency department of a tertiary‐care, level 1 trauma hospital with a nasal bone fracture over a 2‐year period, followed by telephone survey after CNR.ResultsSix hundred seven patients presented to the emergency department in 2015 and 2016 with a diagnosis of nasal bone fracture. Of these, 134 patients met inclusion criteria and underwent CNR without septal reduction. Those with sports‐related injuries and those with a septal fracture identified on computed tomography imaging were significantly more likely to undergo CNR. Ninety‐one patients completed the post‐CNR telephone survey. Over 90% of patients were satisfied with the procedure. However, patients with septal fractures reported worse outcomes, as 53.6% versus 24.1% (P = .0025) disagreed that CNR improved nasal breathing. Of all patients, 11 (2%) eventually underwent septorhinoplasty, with the presence of septal fracture on imaging a significant risk factor.ConclusionsNasal bone fractures are a common injury, often managed initially with CNR. Patients with septal fractures should be counseled on the high risk of posttraumatic nasal deformity and obstruction despite CNR. In addition, addressing a septal fracture found on imaging may be warranted with either closed septal reduction or early aggressive management given the poorer outcomes seen in the present study. Although these patients are more likely to have definitive treatment, many forego later intervention despite persistent symptoms, emphasizing the need for early intervention or close follow‐up.Level of Evidence3Laryngoscope, 129:1784–1790, 2019
Frequency‐dependent empirical modeling for intrinsic output capacitance and conductance of HR PD‐SOI MOSFETs
Authors: Lee Changjo , Lee Seonghearn 
Published: December 2018

AbstractA high resistivity PD‐SOI MOSFET equivalent circuit model including a parallel connection of intrinsic output capacitance and conductance with frequency‐dependent empirical equations is newly proposed to accurately simulate their abrupt change in the low‐frequency region. This new empirical model is superior to a conventional RC one, because equivalent circuit structure and parameter extraction process are simpler. Better agreements with measured Y22‐parameter are obtained for the new model than the conventional one.
Design of a multiband ground radiation antenna by utilizing balun excitation
Authors: Wang Chien‐Jen , Hsu Chia‐Wei 
Published: December 2018

AbstractThe design and performance of a triple‐band ground radiation antenna with a compact balun are shown in this paper. A microstrip balun is integrated with a modified rectangular ground plane has provided wideband frequency characteristics. With the help of the theory of the characteristic mode, the resonance phenomenon of the rectangular ground plane is analyzed. An eight‐like‐loop slit is embedded in the ground plane to excite multiple resonant modes. In, addition, by etching two rectangular slots at two terminals of the eight‐like‐loop slit, the capacitance of the ground‐plane resonator decreases such that the impedance‐matching condition in the upper‐frequency band can be improved. Finally, a triple‐band frequency performance is derived by embedding a simple matching circuit. The proposed antenna achieves the measured impedance bandwidths from 1.02 to 1.06, from 1.35 to 1.62, and from 1.96 to 2.55 GHz. The simulated current distributions of a ground‐plane prototype are also experimentally verified.
Design guidelines for helicone antennas with improved gain
Authors: Sadeghikia Fatemeh , Horestani Ali K. 
Published: December 2018

AbstractThe aim of this study is to present guidelines to design a helicone antenna (helix with conical ground conductor) with an optimum gain while keeping the physical size of the antenna as small as possible. To this end, variations of the antenna gain with the dimensions of the conical ground, including its inner diameter, height, and angle, are numerically computed, and guidelines for accelerating the design and optimization of the antenna are extracted. Note that, in most of applications, a trade‐off between physical compactness and performance of an antenna has to be made. Thus, in this investigation, the guidelines are developed with the aim of achieving a compromise between the maximum radiation gain and minimum physical dimensions. It is shown that following the proposed design guidelines the gain of a helical antenna can be increased up to 5 dB, while the antenna has an acceptable physical size.
Accuracy improvement of micro‐electro‐mechanical system microwave power sensor based on self‐reference algorithm
Authors: Li Chenglin , Liao Xiaoping , Chen Chen 
Published: December 2018

AbstractThis article presents a self‐reference algorithm to improve the accuracy of micro‐electro‐mechanical system thermoelectric microwave power sensor (5‐15 GHz). The output thermovoltage of the sensor is not only a function of the input signal power, but also relates to the signal frequency, resulting in low accuracy of the sensor. In this article, a mathematical model is established for the sensor to analyze the reasons for frequency dependence. Moreover, an algorithm is derived from analyzing the characteristics of the model and the experimental results. The algorithm relieves the dependence on the thermovoltage and frequency. Experiments show that the relative error of the sensor based on the proposed self‐reference algorithm decreases from 22% to 1.6%, and the SD is smaller than 0.4 mW. This self‐reference algorithm plays critical role in the practical application of microwave power sensors.
Design and characterization of the double‐layered defected ground structure transmission line with less radiation loss
Authors: Han Sang‐Min , Kim Jung Ouk , Yoon Won‐Sang , Lim Jongsik , Ahn Dal 
Published: December 2018

AbstractA double‐layered DGS transmission line is proposed with a smaller DGS size and less radiation loss. Changing the air boundary to a dielectric boundary reduces the effective electric length at the DGS aperture area. An equivalent circuit model is introduced to analyze the DGS transmission line and the resonator circuit designs. Due to the increase in the effective dielectric constant, the proposed structure can be realized with less sensitivity to metallic environments. From the experimental results, the proposed double‐layered DGS can achieve a reduction of 90.1% in size and insensitivity at up to 5 mm of separation from the DGS aperture to the metallic plate.
An electric field controlled dual resonator magneto‐electric band‐stop filter
Authors: Popov Maksym A. , Zavislyak Igor V. , Zhou Peng , Li Tianqian , Shah Piyush J. , Howe Brandon M. , McConney Micheal E. , Srinivasan Gopalan , Page Micheal R. 
Published: December 2018

AbstractA band‐stop filter with dual resonators of yttrium iron garnet (YIG) and lead zirconate titanate (PZT) operating in the S‐ and C‐bands was designed and characterized. Such multiferroic composite resonators allow for mechanical strain mediated control of the ferromagnetic resonance frequency of YIG via a DC voltage applied to PZT. The electric field E‐tuning of the central frequency of the individual resonators by 65‐70 MHz has been utilized for the control of the isolation characteristics by 17 dB and to achieve a maximum transmission loss of 37 dB. The 3 dB‐width of the stop‐band can also be tuned between 40 and 100% when a DC voltage is applied to only one of the two resonators. Such E‐tuning of filter characteristics are of interest for applications in communication systems.
Wrapped ultra‐wide band radar sensor based on resistively loaded bow‐tie antenna for near zone sensing applications
Authors: Lee Doojin , Melek William , Shaker George 
Published: December 2018

AbstractThis article presents the pulse radiating and imaging performances of a wrapped resistively loaded bow‐tie antenna (WRLBA) which has a reduced aperture size for utilizing near zone sensing applications. The pulse radiating performances of the WRLBA are investigated and evaluated by comparing to those of the nonloaded wrapped bow‐tie antenna (WBA). The calculated fidelity factor and evaluation factor (EF) of the WRLBA on the boresight direction are 0.97 and 0.07, respectively. The monostatic radar experiment has been shown that two copper targets with a radius of 2 cm are reconstructed at 15 and 20 cm, respectively. Based on the evaluation of the pulse radiating performances and imaging experiment, the proposed WRLBA is a suitable candidate for imaging applications in the vicinity of the targets.
A magnetic‐loop based monopole antenna for GPR applications
Authors: Raza Ali , Lin Wenbin , Liu Yunlin , Sharif Abu Bakar , Chen Yanzheng , Ma Cunliang 
Published: December 2018

AbstractA new planar antenna is proposed for multiple applications in ground‐penetrating radar. The proposed antenna offers ultra‐wide band characteristics ranging from 100 MHz to 6 GHz. The antenna composed of two elements: an electrical tree‐shaped portion and a magnetic loop antenna, made by joining an electrical antenna with a ground plane via 50 Ohm resistor. The loop antenna portion provides a low‐frequency operation without increasing physical size of the antenna. Proposed antenna has relatively small dimensions 20 × 22.5 cm2 as compared with similar antennas covering the same bandwidth. Time domain analysis of this antenna is done to check its performance for applications in impulse‐based radar systems. The antenna has been manufactured and experimental results are added to validate simulation results.
A 3.5 GHz low insertion loss variation CMOS phase shifter
Authors: Tsai Jeng‐Han , Lin Yu‐Hui , Hung Chuan‐Chi 
Published: December 2018

AbstractA 3.5 GHz low insertion loss variation phase shifter has been designed and fabricated on standard 0.18‐μm CMOS process. To achieve over 360° continuously phase tuning range, the phase shifter consists of a switch type phase shifter (STPS) and a reflection type phase shifter (RTPS). The phase‐invertible variable attenuator (PIVA) topology which can provide two states with 180° phase‐shift while maintaining low amplitude imbalance is adopted. The RTPS provides over 189° continuously phase tuning. The experimental results show that the 3.5 GHz phase shifter demonstrates over 360° continuously phase tuning range with low insertion loss variation of 1 dB at 3.5 GHz. The maximum insertion loss is 13.5 dB at 3.5 GHz and the dc consumption is zero. The chip size is 1.08 mm × 0.82 mm.
Bandwidth enhancing method using tri‐ring resonator metamaterial for small devices
Authors: Tamrakar Maruti , Usha Kiran K. 
Published: December 2018

AbstractMetamaterials are composite structures of the specific behavior for electromagnetic properties of permittivity, permeability, and refraction, which are not commonly found in regular materials. Metamaterial structure, which has negative value of permittivity and permeability that shows passband response in transmission line, where as if any of these two properties has opposite polarity then it shows stopband response. These behaviors of metamaterial are frequency dependent and have resonance for particular frequencies. At frequency resonance, the traditional metamaterials have narrow band response and to improve its frequency bandwidth, a method using tri‐ring resonator is proposed with increasing number of order of resonator. The proposed metamaterial structure is simulated in fullwave simulator and MATLAB tool is used to analyze the properties of metamaterial structure from simulated S‐parameter. Proposed technique gives flexibility to use the design for multiple application like, rejection filter for Bluetooth 2.4 GHz, Wi‐Fi (2.4 and 5 GHz), WiMAX (2.5 and 3.4 GHz), and 5G (3.4‐3.8 GHz).
Finite‐horizon Markov population decision chains with constant risk posture
Authors: White Amanda M. , Canbolat Pelin G. 
Published: December 2018

AbstractA Markov population decision chain concerns the control of a population of individuals in different states by assigning an action to each individual in the system in each period. This article solves the problem of finding policies that maximize expected system utility over a finite horizon in Markov population decision chains with finite state‐action space under the following assumptions: (1) The utility function exhibits constant risk posture, (2) the progeny vectors of distinct individuals are independent, and (3) the progeny vectors of individuals in a state who take the same action are identically distributed. The main result is that it is possible to solve the problem with the original state‐action space without augmenting it to include information about the population in each state or any other aspect of the system history. In particular, there exists an optimal policy that assigns the same action to all individuals in a given state and period, independently of the population in that period and such a policy can be computed efficiently. The optimal utility operators that find the maximum of a finite collection of polynomials (rather than affine functions) yield an optimal solution with effort linear in the number of periods. © 2016 Wiley Periodicals, Inc. Naval Research Logistics 65: 580–593, 2018