bluuebunny/crossref_metadata_2025_split huggingface dataset:
Techniques for minimizing sedation in pediatric MRI
Authors: Dong Su‐Zhen , Zhu Ming , Bulas Dorothy 
Published: March 2019

MRI is used widely in infants and young children. However, in these young cases deep sedation or general anesthesia is often required to minimize motion artifacts during MRI examinations. Although the benefits of MR typically outweigh the potential risks of sedation when delivered by an experienced team, there are increasing concerns regarding the affect of sedation on young children. There continues to be a push to develop various strategies that can minimize the need for sedation. The present review summarizes several technical and clinical approaches that can help decrease the need for sedation in the pediatric patient. Optimization of the MRI environment, the role of child life specialists, feed‐and‐bundle and distraction techniques, noise‐reduction methods, artificial intelligence, and MRI advances to decrease both scan times and motion artifacts will be discussed.Level of Evidence: 5Technical Efficacy Stage: 1J. Magn. Reson. Imaging 2019.
Simultaneous high‐performance liquid chromatography with tandem mass spectrometry quantification of six bioactive components in rat plasma after oral administration of Yougui pill
Authors: Liu Haolong , Qiu Feng , Zhao Haiyu , Bian Baolin , Wang Lei 
Published: March 2019

AbstractYougui pills are a classic Chinese medicine that shows significant effects on nerve regeneration and neuroprotection in modern pharmacological studies. With a complex formula, Yougui pills have faced significant challenges in the fields of bioanalysis and pharmacokinetics in animals and human studies. In the present study, a specific and accurate high‐performance liquid chromatography with tandem mass spectrometry method was developed and validated for the quantitative determination of the six bioactive components in rat plasma after oral administration of Yougui pills. Chromatographic separation was performed on a C18 column with a gradient elution system. Samples were analysed using positive ion mode with multiple reaction monitoring mode. The assay showed good linearity for all six bioactive components in the dynamic range of 0.50 to 50 ng/mL with acceptable intra‐ and inter‐batch accuracy and precision. The lower limits of quantification were 0.50 ng/mL for all six bioactive components. The method was successfully applied to rat pharmacokinetics after oral administration of Yougui pills. All six bioactive components were detected in rat plasma, including songorine, benzoylhypaconitine, benzoylmesaconitine, neoline, karacoline, and sweroside, while some other target compounds were not detected, such as rhmannioside A, loganin, and cornuside I. After oral administration of Yougui pills at a dose of 2500 mg/kg, all six bioactive components were rapidly absorbed, resulting in tmax values less than 1 h and relative lower Cmax values. The t1/2 values for songorine, benzoylhypaconitine, benzoylmesaconitine, neoline, karacoline, and sweroside were calculated to be 2.62 ± 0.67, 2.11 ± 0.45, 1.94 ± 0.35, 1.88 ± 0.31, 2.07 ± 0.44, and 1.59 ± 0.30 h, which indicated that Yougui pills should be taken in multiple oral doses over a relatively short period.
Is perception of destination image stable or does it fluctuate? A measurement of three points in time
Authors: Kim Seongseop (Sam) , Stylidis Dimitrios , Oh Munhyang (Moon) 
Published: March 2019

AbstractThis study aimed to identify variations of three types of perceived image including affective, cognitive, and overall image over three points in time and to test the efficacy of image in explaining satisfaction, knowledge, and attachment with a destination. Although previous studies used results collected through a cross‐sectional survey, this study surveyed the same samples at three different times, that is, before, during, and after travel, to enrich our understanding of how image develops through the three key stages of a trip. The findings indicate that there is significant variation in perceived image domains, extracted as a result of factor analysis, and overall image across time. To predict satisfaction, attachment, and knowledge, “vividness” of the affective image domains and “diverse tourism attraction” of the cognitive image domains showed significance on regression models. Interestingly, “developed tourism industry” was not reported being significant predictor in any model. The results suggest that future studies need to measure destination image over time in line with traveler's movement.
Longitudinal change of comprehensive lower urinary tract symptoms and various types of urinary incontinence during robot‐assisted radical prostatectomy
Authors: Fujimura Tetsuya , Igawa Yasuhiko , Aizawa Naoki , Niimi Aya , Yamada Yuta , Sugihara Toru , Kamei Jun , Sato Yusuke , Matsunaga Akiko , Yoshida Mikako , Shinoda Yusuke , Fukuhara Hiroshi , Nakagawa Tohru , Homma Yukio , Kume Haruki 
Published: March 2019

AbstractAimsTo clarify longitudinal change of lower urinary tract symptoms (LUTS) and various types of urinary incontinence following robot‐assisted radical prostatectomy (RARP) using validated questionnaires.Materials and methodsThe core lower urinary tract symptom score (CLSS) and the International Consultation on Incontinence Questionnaire (ICIQ)‐Short Form (SF) questionnaires were administered to 607 consecutive, treatment‐naïve men receiving RARP before and after surgery. The time course of comprehensive LUTS and various types of urinary incontinence, including stress‐, urgency‐, and urinary incontinence with no obvious reason, were evaluated. Continence recovery rates were compared for the different types of incontinence using Cox hazard regression analysis.ResultsAfter surgery, stress urinary incontinence (SUI) was reported most frequently (32% of cases) as the chief complaint with the most impact on daily life, as assessed by the CLSS questionnaire, followed by urgency urinary incontinence (UUI; 27% of cases). The rates of continence recovery differed among the different types of urinary incontinence, such as after urinating, when dressed, when asleep, when physically active or exercising, when coughing or sneezing, before reaching the toilet, and for no obvious reason. Incontinence for no obvious reason at 1 month after RARP was a strongest prognostic factor of delayed continence recovery (hazard ratio, 0.61; P < 0.0001), whereas patients reporting SUI and UUI gradually regained continence.ConclusionsFurther time course on continent recovery after RARP would be more precisely predictable based on the incontinence status at one month postoperatively. Especially, incontinence with no obvious reason would be a significant factor for delayed recovery.
Overactive bladder and associated psychological symptoms: A possible link to vitamin D and calcium
Authors: Abdul‐Razzak Khalid K. , Alshogran Osama Y. , Altawalbeh Shoroq M. , Al‐Ghalayini Ibrahim F. , Al‐Ghazo Mohammad A. , Alazab Rami S. , Halalsheh Omar M. , Sahawneh Feras E. 
Published: March 2019

AbstractIntroductionOveractive bladder (OAB) is a prevalent syndrome that is associated with multiple urinary tract symptoms and could affect the patient's quality of life and well‐being. Vitamin D is shown to be linked to OAB syndrome, which exacerbated by stress conditions. This study evaluated the relationship between vitamin D status, daily calcium intake and OAB, and the associated psychological symptoms.MethodsThe study included 55 patients with OAB and 129 healthy controls. Psychological symptoms were assessed using the Hospital Anxiety and Depression Scale (HADS). Serum vitamin D was measured. Patients with OAB with low vitamin D level received orally vitamin D supplementation. Urinary symptoms, psychological symptoms, and quality of life were evaluated before and after vitamin D supplementation plus dairy products.ResultsVitamin D deficiency was more prevalent in cases (80%) vs controls (34.9%). Depression (43.7% vs 20.2%) and anxiety (52.8% vs 10.9%) scores (HADS, ≥8) were also more frequent in cases vs controls, respectively. Some 85.5% of the patients’ group had musculoskeletal pain vs 0.0% for the control. Depression was negatively correlated with daily calcium intake and positively with anxiety. Logistic regression analysis revealed that age, vitamin D, and anxiety scores were significant predictors of OAB. Vitamin D supplements with increased calcium intake had significant improvement in urinary symptoms, psychological distress, and quality of life.ConclusionsVitamin D supplements and improved calcium intake may improve urinary and psychological symptoms and quality of life among patients with OAB syndrome. Assessment for vitamin D status in patients with OAB may be warranted.
HTPB‐Clay Nanocomposites (HCN): An Efficient Burning Rate Catalyst for Composite Propellant
Authors: Ghosh Kavita , Chimurkar Dhanraj , Kumar Guddu , Kumar Arvind , Banerjee Shaibal , Gupta Manoj 
Published: March 2019

AbstractIn present study, two types of montmorillonite clay, organically modified with polar and apolar moieties, are used, for preparation of HTPB‐clay nanocomposites (HCN) by dispersion of nanoclay in polymer matrix with high shear mixing. These nanocomposites are evaluated in composite propellants for their catalytic effect on decomposition of ammonium perchlorate a work horse oxidizer. Several composite propellant formulations containing 1–3 weight % of nanoclays over binder, were prepared. Along with this, formulations with conventional burning rate catalyst like iron oxide in 1–3 weight % over binder, and formulation without any burning rate catalyst as base composition were also processed. All these formulations were evaluated by means of theoretical prediction, end of mix viscosity, ballistic properties, mechanical properties, sensitivity parameters and thermophysical properties. Experimental results showed that HCN based compositions have lower or comparable end of mix viscosity than base compositions. Further characterization revealed that formulations with 3 weight % of nanoclays over binder have 70 % higher burning rate than base composition as well as 20–25 % higher burning rate than compositions having 3 weight % of iron oxide over binder. Pressure exponent values are determined for 3 to 11 MPa of pressure range and were found to be significantly higher for HCN based compositions (0.33 to 0.7) in comparison to the base composition. Mechanical properties and sensitivity data of HCN based compositions are comparable with base composition. Thermal studies revealed decrease in onset temperature of decomposition of AP with presence of nanoclay which may be the probable cause for enhancement in burning rate.
A Variable‐Rate Firing Optimization of Launcher Based on Particle Swarm Optimization
Authors: He Huizhi , Zhang Xiaobing 
Published: March 2019

AbstractIn the continuous firing process of the launcher, the firing rate is usually taken as a fixed value. As such, there exists an issue that low rate firing lacks shooting efficiency while in high rate firing cases the heat accumulates continuously and the temperature increases rapidly in the barrel of the launcher; consequently, this high temperature threatened the service life of the barrel and the safety of the propellant. In this paper, in contrast to the traditional firing method that has a fixed firing rate, a variable‐rate firing method is proposed to solve this issue. Particle swarm optimization algorithm is exploited in this method to optimize the firing rate (cooling time) of the launcher with the objective that the launcher can conduct the entire shooting in a properly short time while without exceeding the safe temperature of the barrel. The temperature distribution of the barrel is obtained by establishing and solving the coupled model between the interior ballistics and the heat transfer process in the barrel. The optimization results show that the proposed firing method with variable rates can effectively improve the firing rate under the premise of ensuring the safety of the barrel temperature.
Evaluation of cyclodextrin‐micellar electrokinetic capillary chromatography with pyrrolidinium‐based ionic liquid surfactant as a pseudostationary phase for chiral separation
Authors: Yu Tao , Zhang Jinjing , Sun Xiaodong , Du Yingxiang 
Published: March 2019

AbstractIonic liquids have drawn increasing attention in separation science recently. As a new promising brand of surfactants, ionic‐liquid‐based surfactants have their unique properties and superior aggregation behavior, which can be introduced as micelle‐forming surfactants in micellar electrokinetic capillary chromatography mode. There have been few reports of the applications of ionic‐liquid‐based surfactants for micellar electrokinetic capillary chromatography enantioseparation. In this study, pyrrolidinium‐based ionic liquids surfactants were applied for the first time for chiral separation with hydroxypropyl‐β‐cyclodextrin as a chiral selector by micellar electrokinetic capillary chromatography. As observed, the established micellar electrokinetic capillary chromatography systems with ionic‐liquid‐based surfactants could provide better separation of tested chiral drugs than conventional non‐ionic liquid cationic surfactant. In addition, parameters such as the alkyl chain length, concentration of ionic‐liquid‐based surfactants, type and proportion of organic modifier, concentration of chiral selector and composition and pH of buffer solution were systematically investigated to optimize the cyclodextrin‐micellar electrokinetic capillary chromatography system.
Elemental patterns of verification strategies
Authors: Salado Alejandro , Kannan Hanumanthrao 
Published: March 2019

AbstractThis paper proposes a set of seven elemental patterns of verification strategies. These patterns can be useful in modeling verification strategies in a wide range of engineered systems. They form the building blocks under which any verification strategy can be modeled. The patterns lead to a fundamental understanding of the interplay between system parameters and verification activities, as well as an understanding of the mechanisms by which verification evidence builds up. For each pattern, we provide a description and a few examples of its application. A few important theoretical properties of the corresponding set of patterns are discussed, such as belief update, inferential properties, and graph disconnection, as well as some practical guidance to be taken into account when applying them to authentic verification problems. These patterns are intended to be a useful tool for researchers, practitioners, and educators, by formalizing the application of Bayesian networks to verification problems, hence facilitating instruction and communication among verification engineers and with researchers from other domains, particularly statisticians and Bayesian analysts.
Development of Quaternary travertines in the carbonate mountains of the western Costa del Sol, Málaga, southern Spain
Authors: Guerra-Merchán Antonio , Serrano Francisco , García-Aguilar José M. , Ortiz José E. , Torres Trinidad , Sánchez-Palencia Yolanda 
Published: March 2019

AbstractThe predominantly carbonate nature of the mountains near the coast of Málaga and Marbella (Costa del Sol, southern Spain) and the presence of springs have favored the formation of travertine buildups during the Quaternary. The geomorphic characteristics of the slopes and the location of the springs have determined the development of three types of travertine growths: (1) spring travertines, located preferentially on the south mountainside, where the slope is steepest; (2) pool-dam-cascade travertines, which form along the north and east edges, far from the carbonate relief and with a gentler slope; and (3) river-valley travertines, formed in the courses of the springs of any sector. Field observations combined with new amino acid racemization (AAR) dating of Helicidae gastropods show that most of the travertine formations are polyphasic and that their development was interrupted by stages of erosion and incision. Five stages of travertine development are evident, most of which are related to warm, moist episodes corresponding to marine oxygen isotope stages (MIS) 7, 5, 3, and 1, although local travertine growth also occurred during MIS 6 and during the transition from MIS 3 to 2.
The Effects of β-Lactam Antibiotics on Surface Modifications of Multidrug-Resistant Escherichia coli: A Multiscale Approach
Authors: Uzoechi Samuel C. , Abu-Lail Nehal I. 
Published: March 2019

AbstractPossible multidrug-resistant (MDR) mechanisms of four resistant strains of Escherichia coli to a model β-lactam, ampicillin, were investigated using contact angle measurements of wettability, crystal violet assays of permeability, biofilm formation, fluorescence imaging, and nanoscale analyses of dimensions, adherence, and roughness. Upon exposure to ampicillin, one of the resistant strains, E. coli A5, changed its phenotype from elliptical to spherical, maintained its roughness and biofilm formation abilities, decreased its length and surface area, maintained its cell wall integrity, increased its hydrophobicity, and decreased its nanoscale adhesion to a model surface of silicon nitride. Such modifications are suggested to allow these cells to conserve energy during metabolic dormancy. In comparison, resistant strains E. coli D4, A9, and H5 elongated their cells, increased their roughness, increased their nanoscale adhesion forces, became more hydrophilic, and increased their biofilm formation upon exposure to ampicillin. These results suggest that these strains resisted ampicillin through biofilm formation that possibly introduces diffusion limitations to antibiotics. Investigations of how MDR bacterial cells modify their surfaces in response to antibiotics can guide research efforts aimed at designing more effective antibiotics and new treatment strategies for MDR bacterial infections.
Quantitative Determination of Low Contents of Manganese in Steels by EPMA
Authors: Wang Daoling , Sun Aiqin 
Published: March 2019

AbstractThe fluorescence effect induced by Kβ photons is usually so small that it can be neglected. However, in the Fe–Mn system, omitting Kβ fluorescence correction will lead to the overestimation of the Mn content especially when Mn is the minor alloy element. In this study, the error in the Mn concentration induced by Kβ fluorescence was investigated by both Monte Carlo simulation, using the pyPENELOPE program, and systematic electron probe measurements on the Fe–0.53% Mn alloy standard by the aid of CalcZAF software. It is shown that the error caused by Kβ fluorescence exceeds 4% for the Fe–0.53% Mn alloy. The problem can be overcome by utilizing CalcZAF in which β-line fluorescence has been included, or by employing a similar standard Fe–0.85% Mn for Mn in the absence of β-line fluorescence correction. In addition, a modified calibration curve method, using k-values instead of X-ray intensity as a variable, is presented and used to measure the Mn concentration. The accuracy of this method is as good as or better than that of the conventional matrix correction method. Compared with conventional calibration curve methods, it is time-saving because the k-value is not sensitive to instrument fluctuations and the established curve remains valid for a long period.
In situ reversible underwater superwetting transition by electrochemical atomic alternation
Authors: Wang Qianbin , Xu Bojie , Hao Qing , Wang Dong , Liu Huan , Jiang Lei 
Published: March 2019

AbstractMaterials with in situ reversible wettability have attractive properties but remain a challenge to use since the inverse process of liquid spreading is normally energetically unfavorable. Here, we propose a general electrochemical strategy that enables the in situ reversible superwetting transition between underwater superoleophilicity and superoleophobicity by constructing a binary textured surface. Taking the copper/tin system as an example, the surface energy of the copper electrode can be lowered significantly by electrodeposited tin, and be brought back to the initial high-energy state as a result of dissolving tin by removing the potential. Tin atoms with the water depletion layer inhibit the formation of a hydrogen-bonding network, causing oil droplets to spread over the surface, while copper atoms, with a high affinity for hydroxyl groups, facilitate replacing the oil layer with the aqueous electrolyte. The concept is applicable to other systems, such as copper/lead, copper/antimony, gold/tin, gold/lead and gold/antimony, for both polar and nonpolar oils, representing a potentially useful class of switchable surfaces.
Intrinsic photoisomerization dynamics of protonated Schiff-base retinal
Authors: Kiefer Hjalte V. , Gruber Elisabeth , Langeland Jeppe , Kusochek Pavel A. , Bochenkova Anastasia V. , Andersen Lars H. 
Published: March 2019

AbstractThe retinal protonated Schiff-base (RPSB) in its all-trans form is found in bacterial rhodopsins, whereas visual rhodopsin proteins host 11-cis RPSB. In both cases, photoexcitation initiates fast isomerization of the retinal chromophore, leading to proton transport, storage of chemical energy or signaling. It is an unsolved problem, to which degree this is due to protein interactions or intrinsic RPSB quantum properties. Here, we report on time-resolved action-spectroscopy studies, which show, that upon photoexcitation, cis isomers of RPSB have an almost barrierless fast 400 fs decay, whereas all-trans isomers exhibit a barrier-controlled slow 3 ps decay. Moreover, formation of the 11-cis isomer is greatly favored for all-trans RPSB when isolated. The very fast photoresponse of visual photoreceptors is thus directly related to intrinsic retinal properties, whereas bacterial rhodopsins tune the excited state potential-energy surface to lower the barrier for particular double-bond isomerization, thus changing both the timescale and specificity of the photoisomerization.
Brain sugar consumption during neuronal activation detected by CEST functional MRI at ultra-high magnetic fields
Authors: Roussel Tangi , Frydman Lucio , Le Bihan Denis , Ciobanu Luisa 
Published: March 2019

AbstractBlood oxygenation level dependent (BOLD) functional magnetic resonance imaging (fMRI) indirectly measures brain activity based on neurovascular coupling, a reporter that limits both the spatial and temporal resolution of the technique as well as the cellular and metabolic specificity. Emerging methods using functional spectroscopy (fMRS) and diffusion-weighted fMRI suggest that metabolic and structural modifications are also taking place in the activated cells. This paper explores an alternative metabolic imaging approach based on Chemical Exchange Saturation Transfer (CEST) to assess potential metabolic changes induced by neuronal stimulation in rat brains at 17.2 T. An optimized CEST-fMRI data acquisition and processing protocol was developed and used to experimentally assess the feasibility of glucoCEST-based fMRI. Images acquired under glucose-sensitizing conditions showed a substantial negative contrast that highlighted the same brain regions as those activated with BOLD-fMRI. We ascribe this novel fMRI contrast to CEST’s ability to monitor changes in the local concentration of glucose, a metabolite closely coupled to neuronal activity. Our findings are in good agreement with literature employing other modalities. The use of CEST-based techniques for fMRI is not limited to glucose detection; other metabolic pathways involved in neuronal activation could be potentially probed. Moreover, being non invasive, it is conceivable that the same approach can be used for human studies.