bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of both the drive- and sense-mode circuit phase delay on MEMS gyroscope performance and real-time suppression of the residual fluctuation phase error
Authors: Wu Haibin , Zheng Xudong , Wang Xuetong , Shen Yaojie , Jin Zhonghe , Ma Zhipeng
Published: March 2021

This work analyses circuit phase delay for carrier-modulation MEMS capacitive gyroscopes. The temperature-dependent circuit phase delay is a major source of gyroscope output drift, which deteriorates the gyroscope bias instability (BI) and angle random walk (ARW). Effects of both drive-mode and sense-mode circuit phase delay on gyroscope performance when using different signal extraction architectures are analyzed in detail. The online suppression method which combines the so-called modified double sideband (MDSB) extraction architecture in the gyroscope drive mode and closed-loop force-rebalance loop in the sense mode can eliminate the impact of residual fluctuation error of circuit phase delay in real time. When drive-mode circuit phase delay equivalently varies from −20° to 20°, using MDSB decreases the fluctuation of the open-loop zero-rate output (ZRO) by 70% compared to using double sideband (DSB) and by 99.7% with respect to using single sideband (SSB). Meanwhile, improvement for the closed-loop ZRO using MDSB is 92.48% and 94% compared to cases using DSB and SSB, respectively. Furthermore, when the equivalent circuit phase delay of the sense-mode alters from −20° to 20°, ZRO variation for the gyroscope with force rebalanced sense loop and quadrature stiffness nulling loop decreases by 80% in contrast to the case with open loop, which demonstrates the effectiveness of online suppression for circuit phase delay of both the drive-mode and sense-mode. Using the online suppression method, the gyroscope has achieved a BI of 0.16° h−1 and ARW of 0.011° (√h)−1. Furthermore, using the MDSB in the drive mode obtains the best stability compared to using the DSB and SSB as the temperature changes.
Terahertz plasmonic sensing based on tunable multispectral plasmon-induced transparency and absorption in graphene metamaterials
Authors: Li Min , Xiong Cuixiu , Liu Chao , Zeng Biao , Ruan Banxian , Zhang Baihui , Gao Enduo , Li Hongjian
Published: March 2021

Graphene surface plasmons have gained wide interest due to their promising applications in terahertz technology. In this paper, we propose an easily implemented monolayer graphene structure, and exploit its quadra resonance mode to achieve triple plasmon-induced transparency (PIT) and triple plasmon-induced absorption (PIA) effects. A uniform theoretical model with four resonators is introduced to elaborate the intrinsic coupling mechanism and examine the accuracy of simulated results. By altering the Fermi energy and the carrier mobility of the graphene, the proposed triple PIT (PIA) system exhibits a dynamically tunable property, and the absorption intensity can be controlled over a broadband frequency range. It is found that the absorption intensity of the triple PIA spectrum can be as high as 50% with four absorption bands, which is 20 times more than that of monolayer graphene. Besides, we further investigate the triple PIT system for terahertz plasmonic sensing applications, and it is shown that the highest sensitivity of 0.4 THz RIU−1 is reached. Thus, the triple PIT system we propose can be employed for multi-band light absorption and plasmonic optical sensing.
Thioglycolic acid assisted hydrothermal growth of SnS 2D nanosheets as catalysts for photodegradation of industrial dyes
Authors: Zaman M Burhanuz , Poolla Rajaram , Khandy Shakeel Ahmad , Modi Anchit , Tiwari Rajendra Kumar
Published: March 2021

We present our work on the rapid hydrothermal synthesis of highly crystalline 2D SnS nanostructures. An innovative idea is used in which thioglycolic acid is the sulfur precursor source. Structural studies indicate the material has grown in a single-phase orthorhombic structure. The single-phase formation of the material is also confirmed from the rietveld refinement of the experimental XRD data and by raman spectroscopic analysis. Morphological studies show the formation of 2D sheets having thickness in the nanoscale (100–150 nm) dimensions. Optical absorbance studies show the material is visible-light active exhibiting an indirect bandgap of 1.1 eV and direct band gap ∼1.7 eV. Density functional theory calculations support the experimental bandgap results. Photocatalytic activity of the nanosheets was investigated against methylene blue (MB), rhodamine B (RhB) and methyl orange (MO) dyes employing a solar simulator as the source of photons (light source). The nanosheets were found to photodegrade 80% of MB, 77% of RhB and 60% of MO in 120 min of light illumination. Reusability and post catalytic properties affirm the durability and stability of the nanosheets, which is very important in the context of waste water treatment considering the toxic nature of the effluents from dye industries.
Pre-treatment and real-time image guidance for a fixed-beam radiotherapy system
Authors: Liu Paul Z Y , Gardner Mark , Heng Soo Min , Shieh Chun-Chen , Nguyen Doan Trang , Debrot Emily , O’Brien Ricky , Downes Simon , Jackson Michael , Keall Paul J
Published: March 2021

Purpose. A radiotherapy system with a fixed treatment beam and a rotating patient positioning system could be smaller, more robust and more cost effective compared to conventional rotating gantry systems. However, patient rotation could cause anatomical deformation and compromise treatment delivery. In this work, we demonstrate an image-guided treatment workflow with a fixed beam prototype system that accounts for deformation during rotation to maintain dosimetric accuracy. Methods. The prototype system consists of an Elekta Synergy linac with the therapy beam orientated downward and a custom-built patient rotation system (PRS). A phantom that deforms with rotation was constructed and rotated within the PRS to quantify the performance of two image guidance techniques: motion compensated cone-beam CT (CBCT) for pre-treatment volumetric imaging and kilovoltage infraction monitoring (KIM) for real-time image guidance. The phantom was irradiated with a 3D conformal beam to evaluate the dosimetric accuracy of the workflow. Results. The motion compensated CBCT was used to verify pre-treatment position and the average calculated position was within −0.3 ± 1.1 mm of the phantom’s ground truth position at 0°. KIM tracked the position of the target in real-time as the phantom was rotated and the average calculated position was within −0.2 ± 0.8 mm of the phantom’s ground truth position. A 3D conformal treatment delivered on the prototype system with image guidance had a 3%/2 mm gamma pass rate of 96.3% compared to 98.6% delivered using a conventional rotating gantry linac. Conclusions. In this work, we have shown that image guidance can be used with fixed-beam treatment systems to measure and account for changes in target position in order to maintain dosimetric coverage during horizontal rotation. This treatment modality could provide a viable treatment option when there insufficient space for a conventional linear accelerator or where the cost is prohibitive.
Artificial neural networks for positioning of gamma interactions in monolithic PET detectors
Authors: Decuyper Milan , Stockhoff Mariele , Vandenberghe Stefaan , Van Holen Roel
Published: March 2021

To detect gamma rays with good spatial, timing and energy resolution while maintaining high sensitivity we need accurate and efficient algorithms to estimate the first gamma interaction position from the measured light distribution. Furthermore, monolithic detectors are investigated as an alternative to pixelated detectors due to increased sensitivity, resolution and intrinsic DOI encoding. Monolithic detectors, however, are challenging because of complicated calibration setups and edge effects. In this work, we evaluate the use of neural networks to estimate the 3D first (Compton or photoelectric) interaction position. Using optical simulation data of a 50 × 50 × 16 mm3 LYSO crystal, performance is evaluated as a function of network complexity (two to five hidden layers with 64 to 1024 neurons) and amount of training data (1000−8000 training events per calibration position). We identify and address the potential pitfall of overfitting on the training grid through evaluation on intermediate positions that are not in the training set. Additionally, the performance of neural networks is directly compared with nearest neighbour positioning. Optimal performance was achieved with a network containing three hidden layers of 256 neurons trained on 1000 events/position. For more complex networks, the performance degrades at intermediate positions and overfitting starts to occur. A median 3D positioning error of 0.77 mm and a 2D FWHM of 0.46 mm is obtained. This is a 17% improvement in terms of FWHM compared to the nearest neighbour algorithm. Evaluation only on events that are not Compton scattered results in a 3D positioning error of 0.40 mm and 2D FWHM of 0.42 mm. This reveals that Compton scatter results in a considerable increase of 93% in positioning error. This study demonstrates that very good spatial resolutions can be achieved with neural networks, superior to nearest neighbour positioning. However, potential overfitting on the training grid should be carefully evaluated.
An epoch based methodology to denoise magnetocardiogram (MCG) signals and its application to measurements on subjects with implanted devices
Authors: Sengottuvel S , Devi S Shenbaga , Sasikala M , Satheesh Santhosh , Selvaraj Raja J
Published: March 2021

Magnetocardiograms (MCG) provide clinically useful diagnostic information in a variety of cardiac dysfunctions. Low frequency baseline drifts and high frequency noise are inevitably present in routine MCG even for those measured inside magnetically shielded rooms. These interferences sometimes exceed subtle cardiac features in MCG recorded on subjects with implanted devices like cardiac pacemakers; this makes interpretation of cardiac magnetic fields difficult. The present study proposes a correlation-based beat-by-beat approach and principal component analysis to eliminate drifts and high frequency noise respectively; the approach is suitable for denoising both single and multi-channel MCG data. The methodology is critically evaluated on simulated noisy measurements using a 37 channel MCG system, when objects such as implantable permanent pacemaker and stainless-steel wire are sequentially kept externally on the chests of five healthy subjects. By characterizing the noise introduced by each of these objects, the deterioration in the quality of MCG and its subsequent restoration by using the proposed method is assessed. The performance of the proposed method is also compared with other conventional denoising techniques namely, bandpass filters, wavelets and ensemble empirical mode decomposition. The proposed method not only exhibits least distortion, but also preserves the beat-by-beat dynamics of cardiac time series. The method has also been illustrated on actual MCG measurements on two subjects with implanted pacemaker which highlight the ability of the proposed method for denoising MCG in general and during extremely noisy measurement situations.
Chemiresistor sensor matrix prepared by full-printing processes
Authors: Ge Lingpu , Ye Xiao , Chen Bin , Liu Chuanjun , Guo Hao , Sassa Fumihiro , Hayashi Kenshi
Published: March 2021

Herein, we report a novel full printing process for fabricating chemiresistor gas sensor matrixes on photographic paper with an inkjet printer. Sensor matrices, which can increase a number of sensors significantly compared to a serial sensor array, were printed on one piece of A4 photographic paper. Each sensor matrix contains 36 interdigital electrodes in an area of less than 11 mm2, which greatly improves the density of the sensor. The basic architecture of the sensor matrix is electrodes that row and column intersecting. In order to insulate the row and column electrodes from meeting each other, an insulating layer needs to be fabricated at the point of intersection between the row and column electrodes. The insulation layer was produced by adjusting the number of printing passes and shape of the printing pattern of color pigment ink. Carbon black (CB) was used to form a chemosensitive composite by changing its resistivity with a specific polymer for the preparation of sensing material. In order to make the sensing material can be printed, it is necessary to disperse CB first. CB was dispersed in aqueous solution with sodium dodecyl sulfate added as a surfactant to lower the surface tension, which enabled printing of CB using an inkjet printer. Some polymers have certain adsorption characteristics for gases. According to the different gas properties, the adsorption characteristics are also different. By adding polyethylene glycol polymer to the CB layer, the response to four gases with different properties is improved. Compared with the drop coating, the full-printing sensors not only reduces the production time significantly, but also improves the gas response magnitude to ethanol by about three times. The results demonstrate that the developed sensor can be used as a low cost, disposable, and easily printable chemical sensor.
Atomic Cu dispersed ZIF-8 derived N-doped carbon for high-performance oxygen electrocatalysis in Zn-air battery
Authors: Jin Weihua , Lu Zhenjie , Wang Qichao , Zhu Yaming , Pan Haoran , Yao Songdong , Fang Zhigang , Huang Xinning , Chen Xingxing
Published: March 2021

Single-atom catalysts have attracted widespread attention in recent years due to their high atom utilization and excellent catalytic performance, particularly, in oxygen electrocatalysis. Herein, we report to use ZIF-8 as precursor, which was annealed and subsequently mixed with melamine and transition metal salt to finally synthesize Cu-atoms modified N-doped carbon (NC) catalysts, which exhibited excellent oxygen reduction reaction activity and kinetic performance in alkaline solution. The constructed rechargeable Zn-air battery using Cu-NC and benchmark Pt/C catalyst supported on carbon fiber paper as the cathode and anode, respectively, exhibited super good long-term stability with remaining voltaic efficiency of 56% at a charge/discharge current density of 5 mA cm−2 after running 250 cycles (ca. 42 h). Moreover, the power density was as high as 104.5 mW cm−2 at 0.65 V, and such three Zn-air batteries connected in series could light up 34 LED bulbs (2 V and 1.5 W for each) used for constructing a figure of ‘USTL’ for at least 12 h. This research provides a facile method on the synthesis of efficient and cost-effective ORR electrocatalysts in renewable energy storage and conversion systems.
Managing asymptomatic severe rheumatic mitral stenosis in pregnancy: a case report
Authors: Eng-Frost Joanne , Sinhal Ajay , Ilton Marcus , Wing-Lun Edwina
Published: March 2021

Background

Rheumatic heart disease (RHD) is a disease of disparity most prevalent in developing countries and among immigrant populations. Mitral stenosis (MS) is a common sequalae of RHD and affects females disproportionately more than males. Rheumatic MS remains a significant management challenge as severe MS is usually poorly tolerated in pregnancy due to haemodynamic changes and increased cardiovascular demands of progressing pregnancy. Pregnancy remains contraindicated in current management guidelines based on expert consensus, due to a paucity of evidence-based literature.

Case summary

A 28-year-old aboriginal woman with known severe MS was found to be pregnant during routine health review, despite contraceptive efforts. Echocardiography demonstrated mean mitral valve (MV) gradient 14 mmHg; stress echocardiography demonstrated increased MV gradient 28–32 mmHg at peak exercise and post-exercise pulmonary artery pressure 56 + 3 mmHg with marked dynamic D-shaped septal flattening. Left ventricular systolic function remained preserved. She remained remarkably asymptomatic and underwent successful elective induction of labour at 34 weeks. Postpartum, she remained euvolaemic despite worsening MV gradients and new atrial fibrillation (AF). She subsequently underwent balloon mitral valvuloplasty with good result.

Discussion

Severe rheumatic MS in pregnancy carries significant morbidity and mortality, due to an already fragile predisposition towards heart failure development compounded by altered haemodynamics. Pregnancy avoidance and valvular intervention prior to conception or in the second trimester remain the mainstay of MS management; however, we present an encouraging case of successful near-term pregnancy with minimal complications in a medically managed asymptomatic patient with critical MS, who subsequently underwent valvular intervention post-partum.
Left atrial appendage closure device complicated by late-onset pericardial effusion and tamponade: a case report
Authors: Albani Stefano , Berlier Nicola , Pisano Francesco , Scacciatella Paolo
Published: March 2021

Background

Late-onset complications of left atrial appendage occlusion (LAAO) device procedure are anecdotal and there are no such complications reported in literature using Cardia Ultraseal (Cardia, Inc., Eagan, MN, USA).

Case summary

We report the case of a 74-year-old Caucasian man affected by paroxysmal atrial fibrillation with significant bleeding risk (familiar thrombocytopenia, macroscopic haematuria episodes during therapy with direct oral anticoagulants, HAS-BLED risk score: 4) and ischaemic risk as well (CHADSVASC score: 3). The patient was treated with LAAO device implantation for high bleeding risk. Subsequently, after 26 days from LAAO procedure, he was admitted to the emergency department for haematic cardiac tamponade. The patient was successfully treated with subxyphoidal pericardiocentesis in the acute phase, unfortunately cardiac arrest occurred during the transfer to the referral hospital for urgent cardiac surgery. Permanent neurological damage was reported and the patient died on day 28.

Discussion

LAAO late-onset complications are very rare and the case presented is the first case described of late-onset pericardial effusion and tamponade secondary to the Cardia Ultraseal LAAO device implantation. We present a revision of the literature regarding the occurrence of similar adverse events and discuss the hypothetical mechanism of this major complication.
Out with the ‘Old’, in with the ‘New’: Challenging Dominant Regulatory Approaches in the Field of Human Rights
Authors: Frost Neli
Published: March 2021

Mainstream doctrinal and theoretical thinking in international human rights scholarship still adheres to ‘old governance’ regulatory approaches. This is despite the reality of transnational corporations’ (TNCs) increasing involvement in ‘new governance’ architectures in the field of international human rights as regulatory actors and agents of change. ‘Old governance’ approaches are distinguished by statist, positivist regulatory dispositions: they typically position TNCs as violators of human rights; assume a hierarchical relationship between state and society; couple regulation with governments while presuming the state to be the ideal regulator; and, consequently, emphasize power and legal accountability as normative concerns and predominant vehicles for social change. The present article critically reflects on the conceptual, practical and normative implications of this ‘old governance’ bias for contemporary thinking about corporations and human rights under conditions of economic globalization. On the basis of these analyses, the article takes first steps on the path to further theoretical development of a new governance theory for business and human rights. It does so by outlining the importance of new governance perspectives for better evaluating the role that corporate actors actually assume in the field, and what this may mean for these norms’ protection.
State Immunity and Judicial Countermeasures
Authors: Longobardo Marco
Published: March 2021

This article explores whether domestic courts can deny jurisdictional immunity of a state as a countermeasure. The article offers a survey of state practice that, according to some scholars, would support this argument, demonstrating that the corresponding practice is scarce, and that relevant domestic legislation denying jurisdictional immunity is not adopted as a countermeasure. Typically, countermeasures are adopted by political organs, which are responsible for the state’s international relations and which can assess what is a lawful response to a violation of international law. Domestic courts are not entitled to adopt countermeasures without the involvement of the executive organs that are competent for the international relations of the state. This article demonstrates that a domestic court’s denial of sovereign immunity as a countermeasure is unlawful without a prior determination of the government, and it is highly impractical when that determination is provided.
Joseph Krumgold’s …And Now Miguel and Onion John: The Temper of the Times and the Encounter with the Other
Authors: Nodelman Perry
Published: March 2021

A newcomer to writing for children, Joseph Krumgold revealed an intuitive mastery of what led to success in children’s publishing in the 1950s, winning the American Library Association’s Newbery Medal for distinguished contributions to children’s literature for both of his first two novels: …And Now Miguel (1953) and Onion John (1959). An exploration of the novels reveals what made for distinction at that time, what assumptions about excellence for child readers the novels imply, and in doing so, what ideas they foster about who children are and how they do and should read. This essay reads the novels both in the wider context of bestselling 1950s books that offer theories about changing American values, and in terms of the specific values espoused by children’s writers, publishers and librarians. A consideration of these matters reveals a metafictional relationship between the two novels that enriches the insights they offer into assumptions about children’s reading.
Remagnetization of Jutal dykes in Gilgit area of the Kohistan Island Arc: Perspectives from the India–Asia collision
Authors: Jadoon Umar Farooq , Huang Baochun , Zhao Qian , Shah Syed Anjum , Rahim Yasin
Published: March 2021

The Kohistan Island Arc (KIA) occupies the northwestern region of the Himalayan Mountains, sandwiched between Asia and India plates. Its formation, collision with plate boundaries, and evolution has been controversially discussed for a couple of decades. To better understand this, a palaeomagnetic study has been conducted on the Jutal dykes (ca. 75 Ma), intruded in the northeastern part of the KIA. Comprehensive rock magnetic investigations reveal that the magnetic carrier minerals are pyrrhotite and magnetite. An intermediate temperature component (ITC) predominates the natural remanent magnetization and shows good coincidence within-site; it is carried by pyrrhotite and is considered reliable, yielding a mean direction at Dg/Ig = 11.5°/39.9° (kg = 28.4, α95 = 3.5°) before and Ds/Is = 8.6°/12.1° (ks = 5.1, α95 = 9.1°) after tilt correction. A high-temperature component that is carried by magnetite exhibits random distribution within-site. The fold test for the ITC is negative, indicating a post-folding origin. Scanning electron microscopy combined with energy-dispersive X-ray spectroscopy indicates that the magnetic carrier minerals were influenced by metamorphism or thermochemical fluids. The comparison of mean palaeolatitude (22.6 ± 3.5°N) of the ITC with the collisional settings and thermal history of the study area implies that the remagnetization occurred at ∼50–35 Ma, consistent with the previous reported palaeomagnetic data of the KIA. We propose a tectonic model that shows the evolution of the Jutal dykes, supporting the concept that India collided with the KIA first, followed by a later collision with Asia.
Joint inversion for 1-D crustal seismicS- andP-wave velocity structures with interfaces and its application to the Wabash Valley Seismic Zone
Authors: Liu Yuchen , Zhu Lupei
Published: March 2021

Interfaces are important part of Earth’s layering structure. Here, we developed a new model parametrization and iterative linearized inversion method that determines 1-D crustal velocity structure using surface wave dispersion, teleseismic P-wave receiver functions and Ps and PmP traveltimes. Unlike previous joint inversion methods, the new model parametrization includes interface depths and layer Vp/Vs ratios so that smoothness constraint can be conveniently applied to velocities of individual layers without affecting the velocity discontinuity across the interfaces. It also allows adding interface-related observation such as traveltimes of Ps and PmP in the joint inversion to eliminate the trade-off between interface depth and Vp/Vs ratio and therefore to reduce the uncertainties of results. Numerical tests show that the method is computationally efficient and the inversion results are robust and independent of the initial model. Application of the method to a dense linear array across the Wabash Valley Seismic Zone (WVSZ) produced a high-resolution crustal image in this seismically active region. The results show a 51–55-km-thick crust with a mid-crustal interface at 14–17 km. The crustal Vp/Vs ratio varies from 1.69 to 1.90. There are three pillow-like, ∼100 km apart high-velocity bodies sitting at the base of the crust and directly above each of them are a low-velocity anomaly in the middle crust and a high-velocity anomaly in the upper crust. They are interpreted to be produced by mantle magmatic intrusions and remelting during rifting events in the end of the Precambrian. The current diffuse seismicity in the WVSZ might be rooted in this ancient distributed rifting structure.
Sex Differences in the Evolution of Neutralizing Antibodies to Severe Acute Respiratory Syndrome Coronavirus 2
Authors: Grzelak Ludivine , Velay Aurélie , Madec Yoann , Gallais Floriane , Staropoli Isabelle , Schmidt-Mutter Catherine , Wendling Marie-Josée , Meyer Nicolas , Planchais Cyril , Rey David , Mouquet Hugo , Reix Nathalie , Glady Ludovic , Hansmann Yves , Bruel Timothée , De Sèze Jérome , Fontanet Arnaud , Gonzalez Maria , Schwartz Olivier , Fafi-Kremer Samira
Published: March 2021

We measured anti-spike (S), nucleoprotein (N), and neutralizing antibodies in sera from 308 healthcare workers with a positive reverse-transcription quantitative polymerase chain reaction result for severe acute respiratory syndrome coronavirus 2 and with mild disease, collected at 2 timepoints up to 6 months after symptom onset. At month 1, anti-S and -N antibody levels were higher in male participants aged >50 years and participants with a body mass index (BMI) >25 kg/m2. At months 3–6, anti-S and anti-N antibodies were detected in 99% and 59% of individuals, respectively. Anti-S antibodies and neutralizing antibodies declined faster in men than in women, independent of age and BMI, suggesting an association of sex with evolution of the humoral response.
Perceived health-care quality in China: a comparison of second- and third-tier hospitals
Authors: Shi Hongmei , Fan Ming , Zhang Hao , Ma Shaoying , Wang Wenxin , Yan Zhigang , Chen Yuandong , Fan Hongjuan , Bi Ronghua
Published: March 2021

Objectives

To evaluate disparity in service quality between second- and third-tier hospitals and explore factors that affect patients' perception of service quality in China.

Design

Cross sectional study.

Setting

Twelve hospitals in China.

Participants

5714 patients.

Intervention

None.

Main Outcome Measure

Total score of the SERVQUAL scale and each of its five dimensions.

Results

Patients from third-tier hospitals rated significantly higher scores overall and in all the five dimensions of the SERVQUAL scale. Those with lower education, urban residents and those who had higher degree of life satisfaction and attention paid to health perceived higher service quality. Inpatients perceived higher service quality compared with outpatients.

Conclusion

We found a significant gap in patient's perceived service quality between second- and third-tier hospitals in China. A variety of demographic and personality factors were found to significantly influence patient's perceived service quality.
Trade Tax Evasion and the Tax Rate: Evidence from Transaction-level Trade Data
Authors: Mengistu Andualem T , Molla Kiflu G , Mascagni Giulia
Published: March 2021

This paper explores the relationship between tax rates and tax evasion in a low-income country context: Ethiopia. By using transaction-level administrative trade data, we are able to provide an analysis that is largely comparable with the rest of the literature while also introducing two important innovations. First, we compare the elasticity of evasion to statutory tax rates and effective tax rates (ETRs). Most studies in the literature so far focused on the former. We show that ETRs are the most relevant parameter to explain evasion in contexts where exemptions are widespread, which results in a large divergence between ETRs and the statutory rates set out in the law. Second, we account for trade costs more precisely than the previous literature by adjusting the trade gap rather than controlling for proxies. We argue that this new approach to accounting for trade costs is superior to those previously adopted in the literature.
Mass-loss from massive globular clusters in tidal fields
Authors: Meiron Yohai , Webb Jeremy J , Hong Jongsuk , Berczik Peter , Spurzem Rainer , Carlberg Raymond G
Published: March 2021

Massive globular clusters lose stars via internal and external processes. Internal processes include mainly two-body relaxation, while external processes include interactions with the Galactic tidal field. We perform a suite of N-body simulations of such massive clusters using three different direct-summation N-body codes, exploring different Galactic orbits and particle numbers. By inspecting the rate at which a star’s energy changes as it becomes energetically unbound from the cluster, we can neatly identify two populations we call kicks and sweeps that escape through two-body encounters internal to the cluster and the external tidal field, respectively. We find that for a typical halo globular cluster on a moderately eccentric orbit, sweeps are far more common than kicks but the total mass-loss rate is so low that these clusters can survive for tens of Hubble times. The different N-body codes give largely consistent results, but we find that numerical artefacts may arise in relation to the time-step parameter of the Hermite integration scheme, namely that the value required for convergent results is sensitive to the number of particles.
Using interstellar clouds to search for Galactic PeVatrons: gamma-ray signatures from supernova remnants
Authors: Mitchell A M W , Rowell G P , Celli S , Einecke S
Published: March 2021

Interstellar clouds can act as target material for hadronic cosmic rays; gamma rays subsequently produced through inelastic proton–proton collisions and spatially associated with such clouds can provide a key indicator of efficient particle acceleration. However, even in the case that particle acceleration proceeds up to PeV energies, the system of accelerator and nearby target material must fulfil a specific set of conditions in order to produce a detectable gamma-ray flux. In this study, we rigorously characterize the necessary properties of both cloud and accelerator. By using available supernova remnant (SNR) and interstellar cloud catalogues, we produce a ranked shortlist of the most promising target systems, those for which a detectable gamma-ray flux is predicted, in the case that particles are accelerated to PeV energies in a nearby SNR. We discuss detection prospects for future facilities including CTA, LHAASO and SWGO; and compare our predictions with known gamma-ray sources. The four interstellar clouds with the brightest predicted fluxes >100 TeV identified by this model are located at (l,b)  = (330.05, 0.13), (15.82, −0.46), (271.09, −1.26), and (21.97, −0.29). These clouds are consistently bright under a range of model scenarios, including variation in the diffusion coefficient and particle spectrum. On average, a detectable gamma-ray flux is more likely for more massive clouds; systems with lower separation distance between the SNR and cloud; and for slightly older SNRs.
The double quasar Q2138-431: detection of a lensing galaxy
Authors: Hawkins M R S
Published: March 2021

This paper reviews the question of whether the wide separation double quasar Q2138-431 is a gravitational lens. From early work, the two quasar images are known to have almost identical spectra and redshifts, but no lensing galaxy has so far been detected. In this paper, we used recent deep surveys in infrared and optical bands to search for the presence of a galaxy with the expected properties of a gravitational lens. The search revealed a 5σ detection of a faint galaxy between the two quasar images on a deep J-band frame from the VISTA Science Archive, with apparent magnitude J = 20.68. Non-detection in the I-band implied a redshift z > 0.6, and mass modelling of the quasar system gave a mass of $1.31 \times 10^{12} \, \mathrm{M}_\odot$ for the lensing galaxy, with mass-to-light ratio M⊙/L⊙ = 9.0. Archival photographic data from the UK 1.2m Schmidt telescope covering 25 yr were used to construct light curves for the two quasar images, which were then cross-correlated to measure any time lag. This showed image B to lead image A by around a year, consistent with 410 d from the mass model. Although the similarity of the spectra and the detection of the lensing galaxy are the most compelling arguments for the classification of Q2138-431 as a gravitational lens, the time delay and mass-to-light ratio provide a consistent picture to support this conclusion. The wide separation of the quasar images and the simplicity of the mass model make Q2138-431 an excellent system for the measurement of the Hubble constant.
Mobilizing and Demobilizing
Authors: Kam Cindy D , Archer Allison M N
Published: March 2021

Since the 2016 US presidential campaign and the rise of the #MeToo movement, issues of sexual assault and harassment have risen to prominence. At the same time, these issues have also been understood and evaluated through the lens of partisanship. The US Supreme Court confirmation hearings of Brett Kavanaugh exemplified these dynamics by providing clear partisan and emotion-laden cues to citizens. Given these events’ temporal proximity to the midterms, we argue that the confirmation hearings not only amplified an ongoing conversation, but also heightened the effect of sexist predispositions on turnout. Using a unique online survey with validated voter turnout in the 2018 midterms, we find that higher levels of modern sexism increased turnout among Republicans while lower levels of modern sexism increased turnout among Democrats. In 2018, sexist predispositions triggered turnout in opposing ways across the aisle.
Clinical outcomes between long and short proximal femoral nail antirotation (PFNA-II) devices in the management of extracapsular hip fractures: a retrospective cohort study
Authors: Tan Marcus Wei Ping , Vellasamy Anandakumar
Published: March 2021

Background:

Long and short intramedullary nails have been used in the treatment of extracapsular hip fractures. Long nails without distal interlocking screws may provide additional stability while avoiding complications associated with screw insertion, but these have not been well evaluated. This study aims to compare the outcomes of locked short Proximal Femoral Nail Antirotation-II (PFNA-II, Synthes Holding AG, Solothurn, Switzerland) nails and unlocked long PFNA-II nails for the treatment of extracapsular hip fractures.

Methods:

Ninety-one patients at our level I trauma center received these implants (61 long, 30 short). This retrospective cohort study evaluated the days to ambulation, length of stay (LOS), Radiographic Union Score for Hip (RUSH), and complication rate.

Results:

Days to ambulation (4.8±5.1 vs. 5.6±8.6, P=0.29) and LOS (12.6±8.3 vs. 10.4±8.1, P=0.12) were similar between both groups. Although both groups demonstrated significant improvement in RUSH scores between 1 and 3 mo, there were no significant differences between both groups (16.4±2.6 vs. 17.4±2.9, P=0.10; 25.6±3.6 vs. 24.7±3.1, P=0.24). There were more postoperative complications in the long group (29.5% vs. 13.3%), including one patient with malunion in each group.

Conclusions:

The purported extra stability of the unlocked, long PFNA-II device in extracapsular hip fractures has not been demonstrated in this study. Hence, we recommend the short PFNA-II device in extracapsular hip fractures due to its superior cost-benefit advantage.

Level of Evidence:

Level IV.
Single-agent carboplatin in extensive disease small-cell lung cancer patient with liver failure: a case report within the experience of a single institution
Authors: Di Federico Alessandro , Andrini Elisa , Sisi Monia , Nuvola Giacomo , Lamberti Giuseppe , Lenzi Barbara , Nobili Elisabetta , Gelsomino Francesco , Ardizzoni Andrea
Published: March 2021

Until recently, platinum-based chemotherapy has represented the benchmark for the treatment of extensive disease small-cell lung cancer (ED-SCLC). ED-SCLC patients are often diagnosed with poor performance status (PS ≥2) and/or compromised organ functions. In fact, up to 63% of ED-SCLC has extensive liver involvement at diagnosis, which correlates with a poor prognosis. Whether to treat patients with tumor-related organ failure is still debated and the selection of those who could benefit from chemotherapy is crucial. Moreover, severe liver impairment contraindicates the administration of etoposide. Among 74 consecutive ED-SCLC patients followed at our institution from January 2017 to November 2019, three patients received single-agent carboplatin as a first-line treatment due to liver failure. We provide a brief description of a former heavy smoker 70-year-old man who was diagnosed with ED-SCLC and severe liver involvement leading to liver failure. The patient received a first-line treatment with single-agent carboplatin, obtaining a partial response, clinical benefit and the normalization of laboratory test, which documented the complete recovery of liver function. The intent of our work is to highlight the feasibility of single-agent carboplatin in ED-SCLC patients with tumor-related hepatic failure but preserved Eastern Cooperative Oncology Group PS, suggesting that this therapeutic option should not be discouraged a priori. Indeed, the identification of specific tools guiding physicians in the selection of patients who might benefit from the treatment is remarkably needed; meanwhile, the use of available prognostic score (e.g. Manchester score) might be of great value and should be considered in clinical practice.
Dedication in a Difficult Context
Authors: Roberts Lisa R. , Georges Marie , Nick Jan M. , Taylor Elizabeth Johnston
Published: March 2021

Haitian nurses live in a precarious environment, with healthcare disparity and low wages. In the presence of significant politico-social-economic disparities, adverse effects of natural disasters, deleterious infrastructure, challenged self-boundaries, and the burden of caring for high-need patients, the authors sought a better understanding of nurses' perspective of the situation. During qualitative interviews, Haitian nurses in two faith-based hospitals (N = 17) reported feeling powerless yet exhibited resilience and dedication to nursing as a calling. These conditions cry out for support of nurses' self-care needs. Future interventions may help nurses identify better resources to care for themselves and guide their practice.
Keys to Trust-Building with Patients
Authors: Shanahan Tonya , Cunningham Jill
Published: March 2021

A focal point for nurses and nurse practitioners is developing trust within the nurse–patient relationship. A stable foundation of trust between patient and nurse can diminish patients' mistrust of the healthcare system while engaging patients in their own care and improving health outcomes. Trust can be fostered through active listening as well as strengthening verbal and nonverbal communication skills. Biblical elements that undergird a trusting and honest nurse–patient relationship are described along with a patient narrative with some strategies for nursing implementation.
Promoting Healthy Lifestyles in Women Through Faith-Based Outreach
Authors: Leschber Tiffany
Published: March 2021

Faith-based health programs reach broad populations and can reduce health disparities. Nurses working in communities and churches can promote health behaviors that may reduce the incidence and impact of chronic conditions. This 5-week faith-based health outreach resulted in improvement of health-promoting behaviors, including better stress management, among women.
Evaluation of safety after optic exchange of a modular intraocular lens
Authors: Ang Robert Edward T. , Yoo Paul , Liu Jingbo
Published: March 2021

Purpose:

To characterize safety of optic exchange using a modular lens.

Setting:

3 study sites, New Zealand, Philippines.

Design:

Prospective clinical study.

Methods:

Harmoni Modular intraocular lens (HMIOL) with separate base and optic components was implanted in the study eye (monovision target −1.50 diopter). Contralateral eyes received standard monofocal IOLs. Subjects could elect optic exchange 3 months after primary implantation. Adverse events (AEs) and endothelial cell loss (ECL) were assessed through 12 months of follow-up.

Results:

114 subjects successfully received HMIOL and 114 received control lens in contralateral eye. At 3 months, 65 HMIOL eyes had optic exchange because of unsatisfactory visual outcome from high monovision (exchange cohort); 49 eyes received no exchange (no exchange cohort). Exchange, no exchange, and control cohorts reported ocular AEs in 10 (15%), 6 (12%), and 14 (12%) eyes, respectively. No posterior capsular rupture occurred during optic exchange procedures. Short-term (12-month) posterior capsule opacification (PCO) evaluation showed that all eyes had PCO grade 1 or less at 12 months; no Nd:YAG capsulotomy was performed in the exchange cohort. No exchange and exchange cohorts had similar ECL at 3 months vs preoperative baseline (−4.5%, n = 48 and −4.0%, n = 65). In the exchange cohort, additional 2.7% ECL occurred 3 months after optic exchange compared with preexchange baseline; ECL was significantly below the 14% threshold (P < .001) and was 5.8% at 12 months.

Conclusions:

HMIOL safety outcomes were comparable with standard monofocal IOLs; HMIOL may provide an effective method for correcting postoperative refractive errors.
Lethal zoonotic coronavirus infections of humans – comparative phylogenetics, epidemiology, transmission, and clinical features of coronavirus disease 2019, The Middle East respiratory syndrome and severe acute respiratory syndrome
Authors: Hui David S. , Zumla Alimuddin , Tang Julian W.
Published: March 2021

Purpose of review

Severe acute respiratory syndrome-coronaviruses-2 (SARS-CoV-2), the cause of coronavirus disease 2019 (COVID-19), emerged as a new zoonotic pathogen of humans at the end of 2019 and rapidly developed into a global pandemic. Over 106 million COVID-19 cases including 2.3 million deaths have been reported to the WHO as of February 9, 2021. This review examines the epidemiology, transmission, clinical features, and phylogenetics of three lethal zoonotic coronavirus infections of humans: SARS-CoV-1, SARS-CoV-2, and The Middle East respiratory syndrome coronavirus (MERS-COV).

Recent findings

Bats appear to be the common natural source of SARS-like CoV including SARS-CoV-1 but their role in SARS-CoV-2 and MERS-CoV remains unclear. Civet cats and dromedary camels are the intermediary animal sources for SARS-CoV-1 and MERS-CoV infection, respectively whereas that of SARS-CoV-2 remains unclear. SARS-CoV-2 viral loads peak early on days 2–4 of symptom onset and thus high transmission occurs in the community, and asymptomatic and presymptomatic transmission occurs commonly. Nosocomial outbreaks are hallmarks of SARS-CoV-1 and MERS-CoV infections whereas these are less common in COVID-19. Several COVID-19 vaccines are now available.

Of the three lethal zoonotic coronavirus infections of humans, SARS-CoV-2 has caused a devastating global pandemic with over a million deaths. The emergence of genetic variants, such as D614G, N501Y (variants 1 and 2), has led to an increase in transmissibility and raises concern about the possibility of re-infection and impaired vaccine response. Continued global surveillance is essential for both SARS-CoV-2 and MERS-CoV, to monitor changing epidemiology due to viral variants.
Association of Myeloperoxidase Gene Polymorphism With Iron Deficiency Anemia in Turkish Children
Authors: Ustabas Kahraman Feyza , Çakir Fatma Betül , Buhur Pirimoglu Meltem , Torun Emel , Ergen Hayriye Arzu , Doğan Demir Ayşegül
Published: March 2021

This study was performed to investigate the gene polymorphisms of the myeloperoxidase (MPO) enzyme and to determine whether MPO gene polymorphisms influence the response to iron therapy in pediatric patients with iron deficiency anemia (IDA). In this case-control study, 50 Turkish children with IDA and 50 healthy controls were enrolled. Three MPO gene alleles were selected for genotyping in the study: GG, AG, and AA. The relationships of alleles with IDA were analyzed and compared in patients and controls. Pretreatment and posttreatment laboratory parameters and gene polymorphisms were compared in the patient group. There was a significant difference between patients with IDA and controls regarding genotype frequencies of the AA, GG, and AG alleles (P=0.005). However, the AG allele was found to be associated with variations in hemoglobin, red blood cell, hematocrit, mean corpuscular volumes, and mean corpuscular Hb concentrations levels. The frequency of AA, GG, and AG alleles of the MPO gene was potentially associated with changes in iron metabolism and the AG allele led to variations in various hemogram parameters.
The role of plants and macrofungi as a source of novel antimicrobial agents
Authors: Nelson David W. , Millar Beverley C. , Rao Juluri R. , Moore John E.
Published: March 2021

Antibiotic resistance presents a significant challenge to clinical, veterinary and plant health and is now recognized by the WHO as a major emerging problem of global significance. Recently, there has been a paucity of new antibiotics being developed, thus refocussing investigations into natural antimicrobials, especially from plants. Historically, plants have been a rich source of medicines, ranging from chemotherapeutic compounds, anti-inflammatories to antimicrobial agents, where such therapeutic activity has been recognized and exploited by traditional medicine in many countries, particularly in Asia. This review wishes to explore the substances in plants which are antimicrobial and to identify their broad spectrum of activity. In addition, the review discusses the ecological effects of overharvesting of medicinal plants and the consequences for species survival.