bluuebunny/crossref_metadata_2025 huggingface dataset:
Neutron diffraction study of crystal structure and temperature driven molecular reorientation in solid α-CO
Authors: Wang Lijuan , Sun Chuli , Xu Hongwu , Zhang Jianzhong , Zhao Yusheng , Guo Wei , Zhu Jinlong
Published: April 2020

Neutron diffraction studies have been carried out on carbon monoxide (CO) in the temperature range of 14–68 K. From the data of the temperature dependent crystal parameters, the volume thermal expansion β (T), C–O bond length, and intermolecular distance of CO have been determined and compared with calculations. The volume evolution of cubic CO solids indicates a normal thermal expansion. However, the bond length of CO molecules contracts with the increase in temperature. Correspondingly, the distance between CO molecules increases much faster with an increase in the temperature. We find that intermolecular and intramolecular interactions account for these abnormal temperature behaviors of CO molecular crystals. The abnormal change observed in the curve β (T), evolution of C–O bond length, and distance between two CO molecules indicate an order–disorder phase transition induced by head-to-tail reorientations of CO dipoles.
A tool for visualizing protein motions in time-resolved crystallography
Authors: Wickstrand Cecilia , Katona Gergely , Nakane Takanori , Nogly Przemyslaw , Standfuss Joerg , Nango Eriko , Neutze Richard
Published: April 2020

Time-resolved serial femtosecond crystallography (TR-SFX) at an x-ray free electron laser enables protein structural changes to be imaged on time-scales from femtoseconds to seconds. It can, however, be difficult to grasp the nature and timescale of global protein motions when structural changes are not isolated near a single active site. New tools are, therefore, needed to represent the global nature of electron density changes and their correlation with modeled protein structural changes. Here, we use TR-SFX data from bacteriorhodopsin to develop and validate a method for quantifying time-dependent electron density changes and correlating them throughout the protein. We define a spherical volume of difference electron density about selected atoms, average separately the positive and negative electron difference densities within each volume, and walk this spherical volume through all atoms within the protein. By correlating the resulting difference electron density amplitudes with time, our approach facilitates an initial assessment of the number and timescale of structural intermediates and highlights quake-like motions on the sub-picosecond timescale. This tool also allows structural models to be compared with experimental data using theoretical difference electron density changes calculated from refined resting and photo-activated structures.
Improved compensation and measurement of the magnetic gradients in an atomic vapor cell
Authors: Zhan Xiang , Chen Chang , Wang Zhiguo , Jiang Qiyuan , Zhang Yi , Luo Hui
Published: April 2020

Magnetic field gradients reduce the transverse relaxation time of nuclear spins, which usually degrades the sensitivity of atomic sensors based on nuclear spins. We demonstrate improved magnetic field gradient compensation by applying first-order and second-order magnetic gradients simultaneously in a cubic vapor cell containing 87Rb vapor and 129Xe gas. Compared with applying only first-order magnetic gradient compensation, the transverse relaxation time of 129Xe is up to 4.3 times longer when applying both first-order and second-order compensating magnetic gradients, which indicates that the total magnetic gradient is greatly suppressed by the joint compensation in our experiment. The magnetic gradients induced by the polarized 87Rb spins, the static magnetic field, and the residual magnetic field are also explored. As the main sources of internal magnetic inhomogeneities, these gradients are experimentally validated to have a sizable value. Furthermore, the total internal magnetic gradient in the system could be self-compensated when the directions of these internal gradient components are appropriately set. The experimental results in this paper are important for suppressing the magnetic gradients and optimizing the gradient compensation in nuclear magnetic resonance systems.
Real-time machine learning based fiber-induced nonlinearity compensation in energy-efficient coherent optical networks
Authors: Giacoumidis Elias , Lin Yi , Blott Michaela , Barry Liam P.
Published: April 2020

We experimentally demonstrate the world’s first field-programmable gate-array-based real-time fiber nonlinearity compensator (NLC) using sparse K-means++ machine learning clustering in an energy-efficient 40-Gb/s 16-quadrature amplitude modulated self-coherent optical system. Our real-time NLC shows up to 3 dB improvement in Q-factor compared to linear equalization at 50 km of transmission.
Influence of the radial dimension on the high-frequency characteristics in the coaxial relativistic O-type Cherenkov oscillators
Authors: Zhang Jun , Chen Siyao , Zhang Peng , Ge Xingjun , Zhang Jiande
Published: April 2020

Coaxial slow wave structures have always been used to enhance the power handling capacity in the relativistic O-type Cherenkov oscillators generally. However, little attention has been paid to the regularity and the problem it may bring by using large average radius. The aim of this study was to investigate the high-frequency characteristics of coaxial slow wave structures in order to evaluate the influence of the radial dimension comprehensively. The results indicate that a large overmoded ratio can make the power handling capacity increase significantly, but as a result, it will bring some problems such as low efficiency, long starting time, and the difficulty in mode control. In addition, this paper also gives some suggestions and precautions for using large radial dimensions. The conclusion of this paper has strong applicability for the design of coaxial slow wave structures.
In-plane micro-displacement measurement based on secondary diffraction
Authors: Liu Shengrun , Xue Bin , Yu Jirui , Xu Guangzhou , Lv Juan , Cheng Ying , Yang Jianfeng
Published: April 2020

For precision machinery, the measurement of the relative in-plane displacement of two parallel planes that are separated by several meters is important. In this paper, a theoretical model for measuring the relative in-plane microdisplacement between two parallel planes was developed on the basis of secondary diffraction. Based on this method, we employed a pinhole and a circular-ring as the diffraction screens. The influence of the structural parameters of diffraction screens on the secondary diffraction pattern was analyzed in detail, and the obtained parameters were then used in the experimental measurements. For experimental investigation, a laser beam at 532 nm was used to irradiate a pinhole; the diffracted light was then further diffracted using a circular-ring, and the final diffraction pattern was recorded using a CCD camera. The circular-ring was mounted on the plane to be measured, while the pinhole and the CCD camera remained stationary; the space between the pinhole and the circular-ring was set at 1200 mm. The displacement of the circular-ring can be calculated by comparing the central position of the two diffraction patterns before and after shifting the circular-ring. Over a measurement range of 0–90 µm, the absolute error in the displacement measurement was less than 1.97 µm.
Square-shaped structures can topologically guide water waves
Authors: Bandari Anashe
Published: April 2020

Due to its dispersive nature, the topological confinement of water waves is a difficult feat, though it may lead to the development of highly efficient water-wave energy harvesters.
Atomic bridge memristor based on silver and two-dimensional GeSe
Authors: Zhao Mingxing , Li Ranran , Xue Jiamin
Published: April 2020

Memristors store information through a history dependent resistance, which could be used in future computing technologies as a resistive random access memory or to mimic synaptic behaviors with all electronic components. Realizing memristive behavior in the emerging two-dimensional (2D) materials will add new applications to this group of interesting materials. In this study, we successfully fabricate memristors based on a layered 2D material GeSe. Few-layer GeSe flakes are used as the ionic and electronic conductor, and silver is deposited as the active electrode. Reproducible resistance switching is realized in this type of device with the ratio of high resistance to low resistance reaching 104. Thanks to the planar device structure, the conductive path responsible for the resistance state switching is directly imaged with a conductive atomic force microscope. An in situ observation shows that the conductive path is reconfigurable by the polarity of the voltage between the silver and GeSe electrodes. These results demonstrate a facile method for fabricating memristors with 2D materials and provide insights into the resistance switching mechanism.
The speedy secret of shark skin
Authors: Lang Amy W.
Published: April 2020

The outward flaring of a shark’s scales removes drag-producing eddies that otherwise form in the animal’s wake.
Establishment and comparative analysis of HPLC fingerprints of deer tissues
Authors: Yao Mengjie , Zhao Haiping , Qi Xiaoyan , Xu Yuan , Liu Wenyuan , Li Chunyi
Published: April 2020

Context
With the increasing use of velvet antlers (VA) as functional food or traditional Chinese medicine, the quality control has become more and more important.

Aims
Establish an effective method to provide a way of distinguishing VA from other types of deer tissue.

Methods
In the present study, 18 samples from three types of deer tissue were analysed on the basis of high-performance liquid chromatography, and a chromatogram of each sample was obtained. Then, these chromatograms were processed using the similarity evaluation system for chromatographic fingerprints of traditional Chinese medicine, to give the fingerprints of three deer tissues. The chemometric methods were used to analyse the fingerprint results, so as to identify the three types of deer tissue.

Key results
Shared peaks of VA, venison and deer bone were identified using similarity evaluation system. The results showed that, in total, 19 peaks were identified among these three types of deer tissue. Compared with venison, VA lacked three peaks (Numbers 3, 4 and 17); compared with deer bone, VA had six extra peaks (Numbers 2, 5, 8, 9, 14 and 19). The results of chemometric methods showed that different tissue samples could be classified into three categories by using both cluster analysis and principal component analysis. After principal component analysis and partial least-square discrimination analysis, seven peaks were selected, which had significant influence on the classification of VA, venison and deer bone.

Conclusions
The high-performance liquid-chromatography fingerprints in combination with chemometric methods can be used to effectively distinguish three deer tissue types, namely, VA, venison and deer bone.

Implications
We believe the method offers a useful tool much needed in the current Chinese velvet market.
Disentangling the origins of confidence in speeded perceptual judgments through multimodal imaging
Authors: Pereira Michael , Faivre Nathan , Iturrate Iñaki , Wirthlin Marco , Serafini Luana , Martin Stéphanie , Desvachez Arnaud , Blanke Olaf , Van De Ville Dimitri , Millán José del R.
Published: April 2020

The human capacity to compute the likelihood that a decision is correct—known as metacognition—has proven difficult to study in isolation as it usually cooccurs with decision making. Here, we isolated postdecisional from decisional contributions to metacognition by analyzing neural correlates of confidence with multimodal imaging. Healthy volunteers reported their confidence in the accuracy of decisions they made or decisions they observed. We found better metacognitive performance for committed vs. observed decisions, indicating that committing to a decision may improve confidence. Relying on concurrent electroencephalography and hemodynamic recordings, we found a common correlate of confidence following committed and observed decisions in the inferior frontal gyrus and a dissociation in the anterior prefrontal cortex and anterior insula. We discuss these results in light of decisional and postdecisional accounts of confidence and propose a computational model of confidence in which metacognitive performance naturally improves when evidence accumulation is constrained upon committing a decision.
Evidentiality and epistemic modality in the Andean Spanish
verb
Authors: Andrade Ciudad Luis
Published: April 2020

The aim of this chapter is twofold: first, it
assesses the discussion about evidentiality and epistemic modality
in the Andean Spanish verb as a set of hypothetical contact-induced
changes due to the influence of Quechua and Aymara, and, second, it
suggests new avenues for enhancing and strengthening this area of
research. In order to do this, it reviews the studies conducted
about the links between evidentiality and epistemic modality, on the
one hand, and verbal forms such as the pluperfect, the present
perfect, the future, and the subjunctive perfect correlated with
verbs in the present tense, on the other. The review focuses on
studies that address hypothetical contact-induced processes, since
its aim is to examine the arguments that relate these elements with
their possible Quechua and Aymara sources. The chapter suggests that
some of the Andean uses pertain to the epistemic modality terrain
(pluperfect for “non-experienced past” and present perfect for
“experienced past”), while others are included in the evidentiality
arena (inferential uses of the future forms), or plainly lack any
relationship with these dimensions (subjunctive perfect correlated
with verbs in the present tense).
Sensing and structure analysis by in situ IR spectroscopy: from mL flow cells to microfluidic applications
Authors: Kratz Christoph , Furchner Andreas , Sun Guoguang , Rappich Jörg , Hinrichs Karsten
Published: April 2020

In situ mid-infrared (MIR) spectroscopy in liquids is an emerging field for the analysis of functional surfaces and chemical reactions. Different basic geometries exist for in situ MIR spectroscopy in milliliter (mL) and microfluidic flow cells, such as attenuated total reflection (ATR), simple reflection, transmission and fiber waveguides. After a general introduction of linear optical in situ MIR techniques, the methodology of ATR, ellipsometric and microfluidic applications in single-reflection geometries is presented. Selected examples focusing on thin layers relevant to optical, electronical, polymer, biomedical, sensing and silicon technology are discussed. The development of an optofluidic platform translates IR spectroscopy to the world of micro- and nanofluidics. With the implementation of SEIRA (surface enhanced infrared absorption) interfaces, the sensitivity of optofluidic analyses of biomolecules can be improved significantly. A large variety of enhancement surfaces ranging from tailored nanostructures to metal-island film substrates are promising for this purpose. Meanwhile, time-resolved studies, such as sub-monolayer formation of organic molecules in nL volumes, become available in microscopic or laser-based set-ups. With the adaption of modern brilliant IR sources, such as tunable and broadband IR lasers as well as frequency comb sources, possible applications of far-field IR spectroscopy in in situ sensing with high lateral (sub-mm) and time (sub-s) resolution are considerably extended.
Metal Removal from Industrial Waste by Hydrochloric Acid
Authors: Siaw W C , Rakunman M R Musram , Kamaruzaman N , Tsuji T , Manaf N Abdul
Published: April 2020

Leaching of metals from industrial solid waste in hydrochloric acid, HCl solution was studied. In this study, the significant of parameters such as HCl concentration, temperature, liquid to solid ratio and leaching time on the removal percentage of metal impurities were investigated using response surface methodology (RSM) with central composite design (CCD). The ANOVA study concluded that the quadratic model was fitted well to the 27 experimental runs based on p-value (<0.0001), R2 (0.9876) and Adj-R2 (0.9731). This study also revealed that the liquid to solid ratio was the most significant factor for the leaching of metal impurities compared to HCl concentration for this specific industrial solid waste. However, temperature and leaching time showed no significant impact on the leaching rate of metal impurities. Under suitable conditions, a high removal percentage of metal (88 %) was readily achieved at condition of 6 M HCl at 70 °C with liquid to solid ratio of 10 over a leaching period of 70 mins.
Heterogeneous catalyst application in biodiesel production: Needs to focus on cost effective and reusable catalysts
Authors: Jeremiah Peter Abiodun , Jalil Aishah Abdul , Olutoye Moses Aderemi
Published: April 2020

Start your abstract here… Uses of heterogeneous catalyst in bio-energy production also refer to as green energy has been in existence and well researched. Majority of recent heterogeneous catalysts produced focus on optimizing yield of biodiesel from a single feedstock without concerted efforts been made to consider the cost of production. They are mostly developed and produced from synthetic chemicals with their attendants high cost of production. The present review summarizes the needs to produce heterogeneous solid catalyst from wastes and natural resources like clay which is available in all parts of the world.
Beneficial interaction of copper oxide and fibrous silica for enhanced photocatalytic desulphurization
Authors: Hitam C N C , Jalil A A , Shobri N N S M , Fauzi A A
Published: April 2020

Photocatalytic desulphurization (PDS) is considered as a promising technique to remove hazardous sulphur compounds from fuel oil due to its high catalytic activity, safety, low energy consumption, and low cost. In this work, fibrous silica KCC-1 was synthesized by hydrothermal method followed by incorporation of CuO by electrolysis. The catalyst was used for PDS of dibenzothiophene (DBT). The presence of bicontinuous concentric lamellar morphology with uniform spherical shape was confirmed by FESEM analysis. The phase and crystallinity of the catalysts was investigated by XRD, while the band gap energy was determined by UV-Vis DRS. The PDS performance of CuO/KCC-1 was compared with KCC-1, CuO/SiO2 and SiO2. It was observed that the photoactivity of CuO/KCC-1 was higher than other catalysts (62.6%), which is mainly due to its fibrous morphology and appropriate band gap energy, as well as synergistic role of both CuO and KCC-1. This fibrous type catalyst could be a promising candidate for environmental purification specifically in the sulphur removal.
Synthesis of fibrous silica tantalum (FSTa) for photooxidative desulphurization
Authors: Rahim M N S , Jalil A A , Hitam C N C
Published: April 2020

The photooxidative desulphurization (PODS) of dibenzothiophene (DBT) was examined under visible light using fibrous silica tantalum (FSTa), tantalum oxide doped fibrous silica (Ta/KCC-1) and commercial tantalum oxide (Ta2O5). FSTa was synthetized using hydrothermal method, while Ta/KCC-1 was obtained via a wet impregnation method. The catalysts were examined by field emission scanning electron microscopy (FESEM), X-ray Diffraction (XRD) and UV-Vis diffuse reflectance spectroscopy (UV-Vis DRS). It was shown that the FSTa possesses the highest photocatalytic performance (70.2%), due to its fibrous structure, well-dispersion of Ta, as well as its narrower band gap. These traits impact on the photocatalysis by promoting the deposition of the DBT on the catalyst, allowing the efficient transfer of charge carrier and preventing the electron-hole recombination.
Radiation induced graft copolymerization of amine-containing monomer onto polyethylene coated propylene for CO2 adsorption
Authors: Zubair N A , Nasef M M , Ting T M , Abdullah E C , Ahmad A
Published: April 2020

Modification of polyethylene coated polypropylene by radiation-induced graft copolymerization (RIGP) of N-vinylformamide film followed by hydrolysis was studied to produce polyvinylamine (PVAm) containing adsorbent for CO2 adsorption. A number of grafting parameters such as irradiation dose, monomer concentration, and reaction temperature were investigated to obtain desired degree of grafting (DOG) prior to hydrolysis. The DOG was found to be a function of reaction parameters and achieved a desired value of 131% at 40 wt% NVF concentration in toluene, 300 kGy dose, 70°C temperature and 1h reaction time. Subsequently the hydrolysis of formamide groups in the grafted films into amine functionalities was carried out in basic medium. Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscopy (SEM) confirmed the NVF monomer was successfully grafted on PE/PP and consequently the hydrolysis of amide into amine functionalities has occurred in the grafted substrates. The CO2 adsorption capacity of PVAm modified adsorbent was brought to be a function of DOG, which is corresponding to the amine content after hydrolysis. The adsorbent showed the highest CO2 adsorption capacity of 1.32 mmol/g when tested with gas composition of 40% CO2 and 60% nitrogen at room temperature.
Silver Nanoparticles on Pullulan derived via Gamma Irradiation Method: A Preliminary Analysis
Authors: Salleh M.S.N. , Rasit Ali R. , Shameli K. , Hamzah M.Y. , Chan J.Z.
Published: April 2020

Radiation induced technique was employed during the synthesis of silver nanoparticles (AgNPs) on pullulan. In this study, the Ag-NPs on pullulan by γ irradiated process is performed to reduce Ag+ ions at the ambient temperature without using excessive reducing agents or producing unwanted by-products of the reductant. Moreover, reducing agent can be uniformly distributed in the solution and AgNPs are produced in highly pure and stable form. The results from ultraviolet-visible spectroscopy (UV-vis) and XRD demonstrated that the silver nanoparticles can be synthesize using pullulan. This can be confirmed by absorption band of UV-vis spectrum at 420 nm as well as the XRD pattern at (1 1 1), (2 0 0), (2 2 0), and (3 1 1) planes of silver. In addition, the pullulan also acts as a reducing and stabilizing agent. TEM images showed formed AgNPs are spherical in shape with smooth edges. The TEM also revealed that the increasing radiation dose decreases the particle size and increase the rate of reduction. It was found that the mean diameter of silver nanoparticles was about 3.98 -14.87 nm. In addition, the size of the AgNPs is believed can be tuned by controlling the radiation doses. The γ-rays doses also provide the powerful reduction process in a harmless condition by producing a very stable silver nanoparticles.
Green Synthesis of Gold Nanoparticles using Aqueous Extract of Clitoria Ternatea Flower
Authors: Chan J Z , Rasit Ali R , Shameli K , Salleh M S N , Lee K X , Mohamed Isa E D
Published: April 2020

The synthesis of gold nanoparticles (Au-NPs) is being accomplished by the reduction of aqueous gold metal ions, gold(III) chloride trihydrate (HAuCl4.3H2O) reacted with the aqueous flower extract of Clitoria Ternatea (CT). CT flower extract plays an important role in synthesizing Au-NPs. It acts as a reducing (Au3+ to Au) and stabilizing agent that can eliminate the usage of chemicals during the production of Au-NPs. Besides that, it also reduces the production of unwanted by-products which would cause hazardous to the surroundings and environment. In this study, an absorption peak of Au-NPs is observed at the range of 540-550 nm from ultraviolet-visible spectroscopy (UV-vis) analysis. Furthermore, the diffraction peaks at 2θ = 38.44°, 44.41°, 65.03° and 77.58° respectively which correspond to face-centered cubic structure with (111), (200), (220) and (311) plane confirm the successful synthesis of Au-NPs. According to transmission electron microscopy (TEM), the majority of Au-NPs are spherical in shape and having a mean particle size distribution of 18.16 nm with a standard deviation of 4.67 nm.
Estimation of Particulate Emission Generation in Palm Oil Mill Boiler
Authors: Jamian N R , Rashid M , Muzi S M M , Hussein N , Munisamy D , Pa’ad K M , Ali A H M , Yusuf S Y
Published: April 2020

The palm oil industries in Malaysia has been positively growth throughout the year, for it sustainable approach in terms of production and environmental protection. However, this industry also producing considerable amount of particulate emission from the process of burning its biomass waste of palm fibre and shell in the boiler. This study present a method to estimate the particulate emission that are being generated from the boiler. The method were done by analyzing the proximate analysis value of the ash content of palm fibre and shell found in this study. The particulate emission were physically collected from five palm oil mill boilers with boiler capacity ranging from 18-45 tonne/hour. The particulate stack fly ash was collected from the stack gas downstream of a multi-cyclones particulate arrestor according to the USEPA Method 17- Determination of particulate matter emissions from stationary sources. Meanwhile the sample of palm fibre and shell were collected to determine the proximate value. The estimation were then being further analyzed according to the particulate emission that were obtained by the real-stack sampling. In summary, the average moisture content, ash content, volatile matter and fixed carbon for palm shell found in this study are 19.3 ± 5.7%, 2.79 ± 2.2%, 74.3 ± 3.0, and 11.3 ± 4.3, respectively.). The average particulate concentration for these five mills is 2.2±0.9g/Nm3 and the air pollution control requirement are between 64 and 96% with reference to Clean Air Regulations 2014 of 0.15g/Nm3 which is very high to be achieve. It also can be estimated that 26% of the ash generated from the combustion of palm fibre and shell in palm oil mill boiler are being released at the stack.
Hot deformation behavior and microstructural evolution of 2205 duplex stainless steel
Authors: Song Yaohui , Wang Shun , Zhao Guanghui , Li Yugui , Juan Li , Jian Zhang
Published: April 2020

The equiaxed compression test was used to study the microstructure evolution and the dynamic recrystallization behavior of 2205 duplex stainless steel during hot deformation under 850–1100 °C with strain rates of 0.01 s−1, 0.1 s−1, 1 s−1 and 10 s−1. The calculated values of thermal deformation activation energy Q and stress index n were 351.58 kJ mol−1 and 3.8543, respectively. On this basis, the Arrhenius type constitutive equation was successfully established, the microstructure of the sample was studied by electron backscatter diffraction (EBSD), and the changes of the ferrite and austenite phase under different deformation parameters were analyzed. It was seen from the phase boundary and grain boundary diagrams that, at the same temperature, as the deformation rate increased, the austenite phase content slowly decreased, while the ferrite phase content increased. The deformation amount of the two phases under the same strain at different temperatures and strain rates were respectively obtained from the grain orientation scatter diagram and the changes of recrystallization, deformation and substructure under different deformation parameters were obtained from the recrystallization diagram.
Does spatial homogeneity ultimately prevail in nutrient taxis systems? A paradigm for structure support by rapid diffusion decay in an autonomous parabolic flow
Authors: Winkler Michael
Published: April 2020

This work is concerned with the doubly degenerate cross-diffusion system
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that has been proposed as a model for experimentally observable quite complex pattern formation phenomena in bacterial populations.

It is shown that for any initial data satisfying adequate regularity and positivity assumptions, a no-flux initial-boundary value problem for the above in a bounded real interval possesses a global weak solution which is continuous in its first and essentially smooth in its second component.

This solution is seen to asymptotically stabilize in the sense that
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with some nonnegative

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The latter properties are in sharp contrast to known asymptotic features of corresponding nutrient taxis systems involving linear nondegenerate diffusion, as for which the literature appears to exclusively provide results on solutions which approach spatially constant states in the large time limit.
Relationship Between Salt Intake and Blood Pressure in Hypertensive Patients in Beijing
Authors: Wang Hong-yi , He Yong-jie , Li Wei , Yang Fan , Sun Ning-ling
Published: April 2020

Background

To survey the relationship between salt intake and blood pressure in hypertensive patients in Beijing.

Methods

A cross-sectional survey was used. Essential hypertensive patients were enrolled and divided into three groups (low, medium, and high salt intake) according to their 24 h urinary sodium excretion, which was used to access the salt intake. Blood pressure was measured through office measurement and ambulatory blood pressure monitoring.

Results

A total of 2,241 patients were enrolled with a mean age of 59.5 ± 13.8 years, mean blood pressure of 141.1 ± 18.5/84.6 ± 12.7 mm Hg, and urinary sodium excretion of 163.9 (95% CI 160.3–167.4) mmol [equal to salt intake 9.59 (9.38–9.79) g/d]. There were 1,544 cases from tertiary hospitals and the other 697 cases from community hospitals. Patients from community hospitals took more salt than patients from tertiary hospitals. Patients with high salt intake were younger than patients with low and medium salt intake. There were more males in high salt intake group than in the other two groups. Ambulatory blood pressure monitoring showed that patients with high salt intake had higher mean blood pressure not only in daytime, but also at night. The diastolic blood pressure in patients with medium salt intake was higher than that in patients with low salt intake.

Conclusions

Higher salt intake was associated with higher ambulatory blood pressure in hypertensive patients. More effort should be made to lower salt intake to improve blood pressure control rate.
Compatibility of treprostinil sodium and dopamine hydrochloride during simulated Y-site administration
Authors: Bustin Anna , Ramsey E Zachary , Hanna Brian D , Kaushal Gagan
Published: April 2020

Purpose

To evaluate the physical and chemical compatibilities of treprostinil sodium and dopamine hydrochloride.

Methods

Treprostinil sodium (4,000, 76,000, and 500,000 ng/mL) were mixed with dopamine hydrochloride (0.6, 3.2, 6, and 40 mg/mL). Samples were obtained at hours 0, 1, 2, and 4 for physical compatibility and chemical stability testing. Physical compatibility was assessed by visual examination and measurements of turbidity and pH. Drug concentrations were assessed using stability-indicating liquid chromatography mass spectrophotometry (LCMS) for treprostinil sodium and stability-indicating high-performance liquid chromatography (HPLC) for dopamine hydrochloride.

Results

Treprostinil sodium 4,000 and 76,000 ng/mL, when mixed with dopamine hydrochloride 0.6, 3.2, 6, and 40 mg/mL, were stable for 4 hours. Treprostinil sodium 500,000 ng/mL was stable when mixed with dopamine hydrochloride 0.6 mg/mL for 4 hours, but when mixed with dopamine hydrochloride 3.2, 6, and 40 mg/mL, significant precipitation was seen.

Conclusion

Treprostinil sodium 4,000 and 76,000 ng/mL were stable for 4 hours during simulated Y-site coadministration with dopamine hydrochloride 0.6, 3.2, 6, and 40 mg/mL. Treprostinil sodium 500,000 ng/mL is stable when mixed with dopamine hydrochloride 0.6 mg/mL.
Consistency of safety monitoring using routine national databases: results using a quality of care interpretative model
Authors: Labella Barbara , Giannantoni Patrizia , De Blasi Roberta , Caracci Giovanni , Carinci Fabrizio
Published: April 2020

Background

In the framework of targeted action for continuous safety monitoring, we aimed to evaluate the consistency of indicators derived from available databases for regular reporting.

Methods

We used a quality of care interpretative model to select characteristics from five national databases, aggregated and linked by homogeneous groups of providers. The target population included all subjects admitted to public hospitals for acute care in four regions of Italy between 2011 and 2013. The association between structures, processes and safety-related outcomes was investigated using odds ratios from generalized estimating equations logistic regression. Outcome measures included claims of malpractice and five patient safety indicators calculated from discharge abstracts using standardized algorithms.

Results

Over 3 years, claims of malpractice and sepsis increased, whereas deep vein thrombosis and pulmonary embolism decreased. Hospitals with high vs. low volume of discharges were associated with −16% lower rates of claims, but +12% increased risk of sepsis. Compared with research institutes, university clinics had −17% lower rates of claims and −41% cases of dehiscence, with a +32% increased risk of deep vein thrombosis. Local health care authorities recorded −49% deep vein thrombosis, −26% pulmonary embolism, −40% sepsis and +37% risk of claims. Hospitals submitting cases of safe practices and implementing safety recommendations showed significantly higher rates for most outcome measures.

Conclusions

Indicators from regular databases can be conveniently used to develop a national safety monitoring system for hospital care. Although deeper analysis is needed, institutions with a higher propensity to implement safe practices and recommendations consistently showed higher rates of adverse events.
Overlooked and Underestimated: Experiences of Ageism in Young, Middle-Aged, and Older Adults
Authors: Chasteen Alison L , Horhota Michelle , Crumley-Branyon Jessica J
Published: April 2020

Objectives

Although the prevalence of ageism against older people has been well-established, less is known about the characteristics of those experiences or the experiences of young and middle-aged adults. The present study addressed these gaps by examining young, middle-aged, and older adults’ self-reports of an ageist action they experienced.

Methods

Participants’ descriptions were coded for the domain in which the ageist experience occurred, the perpetrator of the ageist experience, and the type of ageist experience.

Results

Young adults most commonly reported experiencing ageism in the workplace with coworkers as perpetrators. Middle-aged and older adults also reported ageism in the workplace; however, they also frequently reported experiencing ageism while seeking goods and services. Perpetrators of ageism varied more widely for middle-aged and older adults. Regardless of one’s age, ageism was commonly experienced in the form of a lack of respect or incorrect assumptions.

Discussion

The findings enhance our understanding of ageism across adulthood by considering the domains, perpetrators, and types of ageist expressions that adults of all ages encounter. They also suggest that interventions to reduce age bias will require multifaceted approaches that take into account the different forms that individuals experience across the life span.
Amikacin initial dosage in patients with hypoalbuminaemia: an interactive tool based on a population pharmacokinetic approach
Authors: Pérez-Blanco Jonás Samuel , Sáez Fernández Eva María , Calvo M Victoria , Lanao José M , Martín-Suárez Ana
Published: April 2020

Objectives

To characterize amikacin population pharmacokinetics in patients with hypoalbuminaemia and to develop a model-based interactive application for amikacin initial dosage.

Methods

A population pharmacokinetic model was developed using a non-linear mixed-effects modelling approach (NONMEM) with amikacin concentration–time data collected from clinical practice (75% hypoalbuminaemic patients). Goodness-of-fit plots, minimum objective function value, prediction-corrected visual predictive check, bootstrapping, precision and bias of parameter estimates were used for model evaluation. An interactive model-based simulation tool was developed in R (Shiny and R Markdown). Cmax/MIC ratio, time above MIC and AUC/MIC were used for optimizing amikacin initial dose recommendation. Probabilities of reaching targets were calculated for the dosage proposed.

Results

A one-compartment model with first-order linear elimination best described the 873 amikacin plasma concentrations available from 294 subjects (model development and external validation groups). Estimated amikacin population pharmacokinetic parameters were CL (L/h) = 0.525 + 4.78 × (CKD-EPI/98) × (0.77 × vancomycin) and V (L) = 26.3 × (albumin/2.9)−0.51 × [1 + 0.006 × (weight − 70)], where CKD-EPI is calculated with the Chronic Kidney Disease Epidemiology Collaboration equation. AMKdose is a useful interactive model-based application for a priori optimization of amikacin dosage, using individual patient and microbiological information together with predefined pharmacokinetic/pharmacodynamic (PKPD) targets.

Conclusions

Serum albumin, total bodyweight, estimated glomerular filtration rate (using the CKD-EPI equation) and co-medication with vancomycin showed a significant impact on amikacin pharmacokinetics. A powerful interactive initial dose-finding tool has been developed and is freely available online. AMKdose could be useful for guiding initial amikacin dose selection before any individual pharmacokinetic information is available.
Dependent Plurality and the Theory of Scalar Implicatures: Remarks on Zweig 2009
Authors: Ivlieva Natalia
Published: April 2020

Following a recent discussion in Fox & Spector 2018, this paper provides an argument for a particular view of the theory of scalar implicatures and exhaustification where exhaustification is only allowed if it alters the overall sentence meaning without weakening it.

I show that this idea is helpful to make sense of the so-called dependent plural interpretations, addressed within the theory of scalar implicatures in Zweig 2009 (see also Zweig 2008). Even though Zweig’s account is based on insightful and plausible assumptions (most crucially, the idea that the multiplicity component of the meaning of plurals is a scalar implicature), it ultimately fails to derive dependent plural readings. The main reason for this is the use of the Strongest Candidate Principle of Chierchia 2006 that happens to filter out the needed interpretation. Replacing the Strongest Candidate Principle with a weaker constraint on exhaustification along the lines of Fox & Spector 2018 resolves the issue, while keeping most of Zweig’s insights intact.
Interventional Study of Dextromethorphan Abuse Within the U.S. Military Community in Okinawa, Japan
Authors: Armstrong Cody , Kapolowicz Michelle R
Published: April 2020

Dextromethorphan, a common over-the-counter cough suppressant, has potential for abuse. In the present commentary, we summarize findings to suggest extensive dextromethorphan overuse/abuse within the U.S. military community residing in Okinawa, Japan. We first compared sales of dextromethorphan-containing medications within the U.S. military community of Okinawa, Japan with sales within the U.S military community from the other nearby locations in the Pacific region. Our report revealed that dextromethorphan use is far more prevalent within the military community in Okinawa. To further substantiate the claim that dextromethorphan abuse is widespread in Okinawa’s U.S. military community, a survey of medical records showed high rates of treatment provided for dextromethorphan intoxication. These findings motivated interventions established throughout the military community in Okinawa to combat dextromethorphan overuse. These stricter policy changes resulted in decreases in sales of dextromethorphan-containing medications as well as a substantial drop in hospital visits from dextromethorphan intoxication, suggesting that the interventions were largely effective and should be maintained.
Paradoxical Contralateral Herniation Detected by Pupillometry in Acute Syndrome of the Trephined
Authors: Fischer Victoria E , Boulter Jason H , Bell Randy S , Ikeda Daniel S
Published: April 2020

Severe traumatic brain injury has historically been a non-survivable injury. Recent advances in neurosurgical care, however, have demonstrated that these patients not only can survive, but they also can recover functionally when they undergo appropriate cerebral decompression within hours of injury. At the present, general surgeons are deployed further forward than neurosurgeons (Role 2 compared to Role 3) and have been provided with guidelines that stipulate conditions where they may have to perform decompressive craniectomies. Unfortunately, Role 2 medical facilities do not have access to computed tomography imaging or intracranial pressure monitoring capabilities rendering the decision to proceed with craniectomy based solely on exam findings. Utilizing a case transferred from downrange to our institution, we demonstrate the utility of a small, highly portable quantitative pupillometer to obtain reliable and reproducible data about a patient’s intracranial pressures. Following the case presentation, the literature supporting quantitative pupillometry for surgical decision-making is reviewed.
Determination of miscalibrated polarization angles from observed cosmic microwave background and foreground EB power spectra: Application to partial-sky observation
Authors: Minami Yuto
Published: April 2020

We study a strategy to determine miscalibrated polarization angles of cosmic microwave background (CMB) experiments using the observed $EB$ polarization power spectra of CMB and Galactic foreground emission. We apply the methodology of Y. Minami et al. (Prog. Theor. Exp. Phys. 2019, 083E02, 2019), developed for full-sky observations to ground-based experiments such as Simons Observatory. We take into account the $E$-to-$B$ leakage and $\ell$-to-$\ell$ covariance due to partial sky coverage using the public code NaMaster. We show that our method yields an unbiased estimate of miscalibrated angles. Our method also enables simultaneous determination of miscalibrated angles and the intrinsic $EB$ power spectrum of polarized dust emission when the latter is proportional to $\sqrt{C_\ell^{EE}C_\ell^{BB}}$ and $C_\ell^{BB}$ is proportional to $C_\ell^{EE}$.
Effects of Pulsed Electromagnetic Field Therapy on Pain, Stiffness, Physical Function, and Quality of Life in Patients With Osteoarthritis: A Systematic Review and Meta-Analysis of Randomized Placebo-Controlled Trials
Authors: Yang Xiaotian , He Hongchen , Ye Wenwen , Perry Thomas A , He Chengqi
Published: April 2020

Objective

Pulsed electromagnetic field (PEMF) therapy is a potentially useful treatment for osteoarthritis (OA), but its effectiveness is still controversial. This study aimed to examine the effects of PEMF therapy and PEMF parameters on symptoms and quality of life (QOL) in patients with OA.

Methods

Cochrane Central Register of Controlled Trials, PubMed, CINAHL, EMBASE, PEDro, clinical trial registers, and reference lists were searched until April 2019. This study examined randomized, placebo-controlled trials, patients with OA, symptom and/or QOL related outcomes, and articles published in English. Two authors extracted data and completed quality assessment.

Results

Sixteen studies were included in our systematic review, while 15 studies with complete data were included in the meta-analysis. Our primary outcome was the standardized mean difference, which was equal to the treatment effect in the PEMF group minus the treatment effect in the placebo group divided by the pooled standard deviation. For pain, the standardized mean difference was 1.06 (95% CI = 0.61 to 1.51), for stiffness 0.37 (95% CI = 0.07 to 0.67), for function 0.46 (95% CI = 0.14 to 0.78), and for QOL 1.49 (95% CI = −0.06 to 3.04). PEMF parameters did not influence symptoms.

Conclusions

Compared with placebo, there was a beneficial effect of PEMF therapy on pain, stiffness, and physical function in patients with OA. Duration of treatment may not be a critical factor in pain management. Further studies are required to confirm the effects of PEMF therapy on QOL.

Impact

Our study suggests that PEMF therapy has clinically significant effects on pain in patients with OA. The current evidence was limited to the short-term effects of PEMF therapy.