bluuebunny/crossref_metadata_2025_split huggingface dataset:
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

Abstract
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

Abstract
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

Abstract
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

Abstract
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

Abstract

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

Abstract

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

Abstract
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

Abstract
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

Abstract
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

SUMMARY
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

SUMMARYInterfaces 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

Abstract
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 &gt;50 years and participants with a body mass index (BMI) &gt;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

Abstract

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

Abstract
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

ABSTRACTMassive 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.