bluuebunny/crossref_metadata_2025 huggingface dataset:
Development and evaluation of an online medication safety module for medical students at a rural teaching hospital: the Winchester District Memorial Hospital
Authors: Elbeddini Ali , Tayefehchamani Yasamin
Published: May 2021

Objective

To design, implement and assess an online learning module for third-year and fourth-year medical students addressing medication safety.

Design

This study was a prospective, parallel, open-label, randomised controlled trial with two arms: (1) a control arm in which students were given five articles to read about medication safety, and (2) an intervention arm in which students were given access to an interactive web-based learning module on medication safety. Pretesting and post-testing were done online to evaluate change in medication safety knowledge.

Results

Ten students completed the study in the intervention group (online module) and six students completed the study in the control group. The increase in score obtained on the post-test, relative to the pretest, was 15.4% in the group who completed the online module and 2.0% in the control group (difference=13.4%, 95% CI 0.5% to 26.2%, p=0.04).

Conclusion

Students who completed an online educational tool about medication safety demonstrated a significantly greater increase in knowledge than those who completed a few readings. Online learning modules can be a convenient and effective means of teaching safe prescribing concepts to medical trainees.
Distinct morning and evening fatigue profiles in gastrointestinal cancer during chemotherapy
Authors: Lin Yufen , Bailey Donald E , Docherty Sharron L , Porter Laura S , Cooper Bruce , Paul Steven , Kober Kord , Hammer Marilyn J , Wright Fay , Conley Yvette , Levine Jon , Miaskowski Christine
Published: May 2021

Background

Purposes were to identify subgroups of patients with gastrointestinal cancers with distinct morning and evening fatigue severity profiles and evaluate for differences among these subgroups in demographic and clinical characteristics, co-occurring symptoms and quality of life (QOL) outcomes.

Methods

Patients with gastrointestinal cancers (n=405) completed questionnaires six times over two cycles of chemotherapy. Latent profile analysis was used to identify distinct morning and evening fatigue profiles. Differences in demographic and clinical characteristics, co-occurring symptoms and QOL outcomes among the subgroups were evaluated using parametric and nonparametric tests.

Results

Two distinct mornings (ie, low and very high) and three distinct evenings (ie, low, moderate and very high) fatigue classes were identified. Common risk factors for both morning and evening fatigue included younger age, lower performance status, higher comorbidity burden and self-reported depression. Higher levels of morning fatigue were associated with being unmarried, living alone, being unemployed, having a lower income, lack of regular exercise and a self-reported diagnosis of anaemia. Higher levels of evening fatigue were associated with being women, white and having childcare responsibilities. Patients in the very high morning and evening fatigue classes reported higher levels of anxiety, depressive symptoms, sleep disturbance and pain and lower levels of attentional function and poorer QOL.

Conclusion

Findings provide new insights into risk factors for and deleterious effects of morning and evening fatigue in patients with gastrointestinal cancers. Clinicians can use this information to identify high-risk patients and develop individualised interventions for morning and evening fatigue and other co-occurring symptoms.
Describing taste changes and their potential impacts on paediatric patients receiving cancer treatments
Authors: Loves Robyn , Green Gloria , Joseph-Frederick Zakia , Palmert Sasha , Plenert Erin , Schechter Tal , Tomlinson Deborah , Vettese Emily , Zahra Serena , Zupanec Sue , Dupuis L Lee , Sung Lillian
Published: May 2021

Objectives

Taste changes are common among paediatric patients receiving cancer treatments although specific descriptions and associations are uncertain. Primary objective was to describe the number of paediatric patients receiving cancer therapies who experienced taste changes, its impact on food intake and enjoyment of eating, and coping strategies.

Methods

This was a cross-sectional study that included English-speaking paediatric patients aged 4–18 years with a diagnosis of cancer or haematopoietic stem cell transplantation recipients receiving active treatment. Using a structured interview, we asked participants about their experience with taste changes, impacts and coping strategies. The respondent was the paediatric patient.

Results

We enrolled 108 patients; median age was 11 years (IQR 8–15). The taste changes reported yesterday or today were food tasting bland (34%), bad (31%), different (27%), bitter (25%), extreme (19%), metallic (15%) or sour (12%). Taste changes were associated with decreased food intake (31%) and decreased enjoyment in eating (25%) yesterday or today. The most common coping strategies were eating food they liked (42%), eating strong-tasting food (39%), drinking liquids (35%), brushing teeth (31%) and sucking on candy (25%). Factors significantly associated with food tasting bad were as follows: older age (p=0.003), shorter time since cancer diagnosis (p=0.027), nausea and vomiting (p=0.008) and mucositis (p=0.009).

Conclusions

Among paediatric patients receiving cancer treatments, taste changes were common and were associated with decreased food intake and enjoyment in eating. Common coping strategies were described. Reducing nausea, vomiting and mucositis may improve taste changes.
Socioeconomic gaps over time in colorectal cancer survival in England: flexible parametric survival analysis
Authors: Kajiwara Saito Mari , Quaresma Manuela , Fowler Helen , Benitez Majano Sara , Rachet Bernard
Published: May 2021

Background

Despite persistent reports of socioeconomic inequalities in colorectal cancer survival in England, the magnitude of survival differences has not been fully evaluated.

Methods

Patients diagnosed with colon cancer (n=68 169) and rectal cancer (n=38 267) in England (diagnosed between January 2010 and March 2013) were analysed as a retrospective cohort study using the National Cancer Registry data linked with other population-based healthcare records. The flexible parametric model incorporating time-varying covariates was used to assess the difference in excess hazard of death and in net survival between the most affluent and the most deprived groups over time.

Results

Survival analyses showed a clear pattern by deprivation. Hazard ratio of death was consistently higher in the most deprived group than the least deprived for both colon and rectal cancer, ranging from 1.08 to 1.17 depending on the model. On the net survival scale, the socioeconomic gap between the most and the least deprived groups reached approximately −4% at the maximum (−3.7%, 95% CI −1.6 to −5.7% in men, −3.6%, 95% CI −1.6 to −5.7% in women) in stages III for colon and approximately −2% (−2.3%, 95% CI −0.2 to −4.5% in men, −2.3%, 95% CI −0.2 to −4.3% in women) in stage II for rectal cancer at 3 years from diagnosis, after controlling for age, emergency presentation, receipt of resection and comorbidities. The gap was smaller in other stages and sites. For both cancers, patients with emergency presentation persistently had a higher excess hazard of death than those without emergency presentation.

Conclusion

Survival disparities were profound particularly among patients in the stages, which benefit from appropriate and timely treatment. For the patients with emergency presentation, excess hazard of death remained high throughout three years from the diagnosis. Public health measures should be taken to reduce access inequalities to improve survival disparities.
Identification and validation of viral antigens sharing sequence and structural homology with tumor-associated antigens (TAAs).
Authors: Ragone Concetta , Manolio Carmen , Cavalluzzo Beatrice , Mauriello Angela , Tornesello Maria Lina , Buonaguro Franco M , Castiglione Filippo , Vitagliano Luigi , Iaccarino Emanuela , Ruvo Menotti , Tagliamonte Maria , Buonaguro Luigi
Published: May 2021

Background

The host’s immune system develops in equilibrium with both cellular self-antigens and non-self-antigens derived from microorganisms which enter the body during lifetime. In addition, during the years, a tumor may arise presenting to the immune system an additional pool of non-self-antigens, namely tumor antigens (tumor-associated antigens, TAAs; tumor-specific antigens, TSAs).

Methods

In the present study, we looked for homology between published TAAs and non-self-viral-derived epitopes. Bioinformatics analyses and ex vivo immunological validations have been performed.

Results

Surprisingly, several of such homologies have been found. Moreover, structural similarities between paired TAAs and viral peptides as well as comparable patterns of contact with HLA and T cell receptor (TCR) α and β chains have been observed. Therefore, the two classes of non-self-antigens (viral antigens and tumor antigens) may converge, eliciting cross-reacting CD8+T cell responses which possibly drive the fate of cancer development and progression.

Conclusions

An established antiviral T cell memory may turn out to be an anticancer T cell memory, able to control the growth of a cancer developed during the lifetime if the expressed TAA is similar to the viral epitope. This may ultimately represent a relevant selective advantage for patients with cancer and may lead to a novel preventive anticancer vaccine strategy.
Histopathological analysis of retrieved thrombi from patients with acute ischemic stroke with malignant tumors
Authors: Kataoka Yuko , Sonoda Kazutaka , Takahashi Jun C , Ishibashi-Ueda Hatsue , Toyoda Kazunori , Yakushiji Yusuke , Kusaka Hirofumi , Koga Masatoshi
Published: May 2021

Background

The procoagulant state in cancer increases the thrombotic risk, and underlying cancer could affect treatment strategies and outcomes in patients with ischemic stroke. However, the histopathological characteristics of retrieved thrombi in patients with cancer have not been well studied. This study aimed to assess the histopathological difference between thrombi in patients with and without cancer.

Methods

We studied consecutive patients with acute major cerebral artery occlusion who were treated with endovascular therapy between October 2010 and December 2016 in our single-center registry. The retrieved thrombi were histopathologically investigated with hematoxylin and eosin and Masson’s trichrome staining. The organization and proportions of erythrocyte and fibrin/platelet components were studied using a lattice composed of 10×10 squares.

Results

Of the 180 patients studied, 17 (8 women, age 76.5±11.5 years) had cancer and 163 (69 women, age 74.1±11.2 years) did not. Those with cancer had a higher proportion of fibrin/platelets (56.6±27.4% vs 40.1±23.9%, p=0.008), a smaller proportion of erythrocytes (42.1±28.3% vs 57.5±25.1%, p=0.019), and higher serum D-dimer levels (5.9±8.2 vs 2.4±4.3 mg/dL, p=0.005) compared with the non-cancer cases. Receiver operating characteristic curve analysis showed the cut-off ratio of fibrin/platelet components related to cancer was 55.7% with a sensitivity of 74.8%, specificity 58.8% and area under the curve (AUC) value of 0.67 (95% CI 0.53 to 0.81), and the cut-off ratio of erythrocyte components was 44.7% with a sensitivity of 71.2%, specificity 58.9% and AUC value of 0.66 (95% CI 0.51 to 0.80).

Conclusions

Thromboemboli of major cerebral arteries in patients with cancer were mainly composed of fibrin/platelet-rich components.
Iatrogenic cerebral radiation necrosis
Authors: Hilton Carolina Maria Helena , Specht Lena , Loebner Lund Eva , Martens Pernille Christina , Schmidt Grethe , Krarup Lars-Henrik
Published: May 2021

Cerebral radiation necrosis is the most serious late reaction to high doses of ionising radiation to the brain, and its treatment is generally unsatisfactory. We present a patient who developed cerebral radiation necrosis after protracted fluoroscopy during repeated embolisations of an extracranial arteriovenous malformation. Treatment with bevacizumab (a humanised murine monoclonal antibody against vascular endothelial growth factor) was followed by neurological and radiological improvements.
CT-like images of the sacroiliac joint generated from MRI using susceptibility-weighted imaging (SWI) in patients with axial spondyloarthritis
Authors: Deppe Dominik , Hermann Kay-Geert , Proft Fabian , Poddubnyy Denis , Radny Felix , Protopopov Mikhail , Makowski Marcus R , Diekhoff Torsten
Published: May 2021

Background

To analyse the added value of susceptibility-weighted imaging (SWI) compared with standard T1-weighted (T1) MRI for detecting structural lesions of the sacroiliac joint (SIJ) in patients with axial spondyloarthritis (axSpA) using CT as reference standard.

Material and methods

Sixty-eight patients with suspected or proven axSpA underwent both MRI and CT of the SIJ on the same day. Two readers separately scored CT, T1 and SWI for the presence of erosions, sclerosis and joint space changes using an established 24-region SIJ model. Disagreement was resolved by a third reader. Diagnostic accuracy (McNemar test), Cohen’s kappa (k), sensitivity (SE) and specificity were calculated on the joint level using CT as reference.

Results

In CT, 38 joints showed erosions, 67 sclerosis and 37 joint space changes. Agreement with CT for erosions was 92.6% (k=0.811 (0.7–0.92)) in SWI and 87.5% (k=0.682 (0.54–0.82)) in T1 (p=0.143) and agreement for sclerosis 84.6% (k=0.69 (0.57–0.81)) and 62.5% (k=0.241 (0.13–0.35)) (p<0.001), respectively. This resulted in superior SE of SWI (81.6% vs 73.7%) for erosions and sclerosis (74.6% vs 23.9%) at a minor expense of SP. No differences were detected for joint space changes.

Conclusion

In patients with axSpA, SWI depicts erosions and sclerosis more accurately than T1 spin echo MRI at 1.5 T.
Seismic response and design of steel multi-tiered concentrically braced frames of the conventional construction category in moderate seismic regions of Eastern Canada
Authors: Derakhshan Houreh Eshagh , Imanpour Ali
Published: May 2021

This study examines the seismic behaviour of steel multi-tiered concentrically braced frames (MT-CBFs) of the conventional construction category (Type CC) in moderate seismic regions of eastern Canada and proposes a new seismic design method for such structures. A total of 32 prototype MT-CBFs part of a single-storey building are selected and designed in accordance with the 2019 Canadian steel design standard (CSA S16-19) provisions for Type CC structures, excluding the design requirements prescribed for frames taller than 15 m, namely the amplification of seismic forces varying by the frame height and the amplification of the column factored seismic force. Nonlinear response history analyses are then performed to examine their seismic response. The results confirmed that tiers experience limited lateral deformation, intermediate horizontal struts are required between tiers, and columns are subjected to combined axial force and bi-axial bending, which in some cases led to column buckling. The results are used to propose a new seismic design method in the framework of CSA S16.
Modelling specific gravity and diameter inside bark of western hemlock and Sitka spruce growing in southeast Alaska
Authors: Dahlen Joseph , Auty David , Lowell Eini
Published: May 2021

Western hemlock (Tsuga heterophylla (Raf.) Sarg.) and Sitka spruce (Picea sitchensis (Bong.)) are two commercially important species in Alaska, with harvests beginning to focus on naturally regenerated young-growth. We developed within-tree models of ring specific gravity (SG) and diameter inside bark (DIB) for young-growth western hemlock and Sitka spruce. Eight even-aged stands (age <75 years) in southeast Alaska were felled and disks collected from multiple height levels; 128 trees and 451 disks were collected for western hemlock, and 217 trees and 952 disks were collected for Sitka spruce. Radial strips were prepared and scanned using X-ray densitometry. We fitted nonlinear mixed-effects models to the data, with cambial age, height within tree, and dominance class used as explanatory variables. The R2 values (fixed effects only) for the SG models were 0.48 and 0.42 for western hemlock and Sitka spruce, respectively. The corresponding fit indices (R2) for the DIB models were 0.86 and 0.85 for western hemlock and Sitka spruce, respectively. Tree maps depicting the within-tree variation in SG showed more variability in Sitka spruce than in western hemlock. The wood and growth properties of young-growth trees in Alaska will continue to become more important as the US Forest Service transitions away from harvesting old-growth trees.
Renal expression and urinary excretion of aquaporin-2 in postobstructive uropathy in rats
Authors: Brandoni Anabel , Torres Adriana M.
Published: May 2021

This work assessed the time course of water renal management together with aquaporin-2 (AQP2) kidney expression and urinary AQP2 levels (AQP2u) in obstructive nephropathy. Adult male Wistar rats were monitored after 1, 2, and 7 days of bilateral ureteral release (bilateral ureteral obstruction (BUO); BUO-1, BUO-2 and BUO-7). Renal water handling was evaluated using conventional clearance techniques. AQP2 levels were assessed by immunoblotting and immunohistochemical techniques. AQP2 expression in apical membranes was downregulated in BUO-1 rats and upregulated both in BUO-2 and BUO-7 animals. AQP2 protein expression in whole cell lysate fraction from kidney cortex and medulla were significantly decreased in all the experimental groups. Concomitantly, mRNA levels of AQP2 decreased in renal medulla of all groups and in renal cortex from BUO-1; however, in renal cortex from BUO-2 and BUO-7 a recovery and an increase in the level of AQP2 mRNA were, respectively, observed. BUO-7 group showed a significant increase in AQP2u. The alterations observed in apical membranes AQP2 expression could explain, at least in part, the evolution time of water kidney management in the postobstructive phase of BUO. Additionally, the AQP2u increase after 7 days of ureteral release may be postulated as a biomarker of improvement in the kidney function.
Transformation of electrical energy into hydrogen and its storage
Authors: Wanner Manfred
Published: May 2021

The German national hydrogen strategy strongly supports the development of technologies to produce, store and distribute green hydrogen in large quantities to reduce greenhouse gas emissions. In the public debate, it is often argued that the economic success of green hydrogen depends primarily on improved efficiencies, and reduced plant costs over large volumes and higher capacities. However, an economy based on the large-scale use of green hydrogen must also take into account the thermodynamic and technical limitations of the processes and components. This study therefore aims to assess the main technical challenges of the German approach to the large-scale use green hydrogen as a future energy carrier.
Wormhole inducing inflation in Kaluza–Klein cosmology
Authors: Biswas Gargi , Sarkar Kaushik , Modak B.
Published: May 2021

We present wormhole as a solution of Euclidean field equations as well as the solution of Wheeler–DeWitt equation in (4 + 1)-dimensional Kaluza–Klein cosmology minimally coupled with scalar field. A simple analytic solution of the Euclidean field equations enlightens classical forbidden domain in the wormhole configuration under analytic continuation in the Euclidean space by [Formula: see text]. Numerical solutions of the field equations allow wormhole configuration with some standard potentials. The wormhole solution triggers decay of potential and reduction of internal space. Cosmic evolution of a wormhole shows an inflationary era away from the classical forbidden domain introducing aforesaid analytic continuation. Analytic and numerical solution of the Wheeler–DeWitt equation also supports Hawking–Page wormhole boundary conditions.
Quantum Bohmian description of a primordial universe with Fermionic and Bosonic sources
Authors: Ribas Marlos O. , Devecchi Fernando P. , Kremer Gilberto M.
Published: May 2021

We present a model of an early universe where the sources of gravitational effects are a scalar field, a relativistic fluid based on Schutz’s model and a self-interacting fermionic field. From the classical analysis based on the Hamiltonian formalism we show that the scale factor of the universe can be expressed in terms of a conformal time that emerges from the fluid’s degrees of freedom. From the Wheeler–DeWitt equation, a wave packet solution as function of the conformal time is determined. It is shown that the combination of the scalar and the fermionic field furnishes a consistent quantum regime and a smooth transition to the classical description, working with the aid of the Bohmian mechanics and in particular with the concept of quantum potential. The influence of the presence of the scalar field is also discussed.
Analysis of the Hidden-charm Tetraquark molecule mass spectrum with the QCD sum rules
Authors: Wang Zhi-Gang
Published: May 2021

In this paper, we investigate the mass spectrum of the ground state hidden-charm tetraquark molecular states without strange, with strange and with hidden-strange via the QCD sum rules in a comprehensive way and revisit the assignments of the [Formula: see text], [Formula: see text], [Formula: see text] states in the scenario of tetraquark molecular states consistently based on the QCD sum rules.
Research on MEMS multi-point exploding metal foil synchronous array
Authors: Chen Jianhua , Li Jiao , Wang Yin , Ren Wei , Li Hui
Published: May 2021

Based on MEMS technology, this paper realized the chip preparation of the synchronous initiation array and obtained the ideal process parameters. The MEMS multi-point exploding metal foil synchronous array chip replaces the traditional initiation array composed of electric detonators, and has a greatly reduced volume and could be prepared in batches. By testing the electrical explosion parameters of the array chip, the peak voltage, peak current, peak time and other data of different ignition voltages are obtained. At the same time, we proposed a method to test the synchronization of the array using multi-channel photonic doppler velocimetry, and obtained the synchronization data when the firing voltage was 2500 V and 2800 V, which provided help for the subsequent optimization design.
Compact Triple/Quadruple-Band Reconfigurable Monopole Antenna for Wireless Applications
Authors: Zugari Asmaa , Ali Wael Abd Ellatif , Salamin Mohammad Ahmad , Hamham El Mokhtar
Published: May 2021

In this paper, a compact reconfigurable tri-band/quad-band monopole antenna is presented. To achieve the multi-band behavior, two right-angled triangles were etched in a conventional rectangular patch, and a partial ground plane is used. Moreover, the proposed multi-band antenna is printed on a low cost FR4 epoxy with compact dimensions of 0.23[Formula: see text], where [Formula: see text] is calculated at the lowest resonance frequency. To provide frequency agility, a metal strip which acts as PIN diode was embedded in the frame of the modified patch. The tri-band/quad-band antenna performance in terms of reflection coefficient, radiation patterns, peak gain and efficiency was studied. The measured results are consistent with the simulated results for both cases. The simple structure and the compact size of the proposed antenna could make it a good candidate for multi-band wireless applications.
Snowball Earth Bifurcations in a Fully-Implicit Earth System Model
Authors: Mulder Thomas E. , Goelzer Heiko , Wubs Fred W. , Dijkstra Henk A.
Published: May 2021

There is now much geological evidence that the Earth was fully glaciated during several periods in the geological past (about 700[Formula: see text]Myr ago) and attained a so-called Snowball Earth (SBE) state. Additional support for this idea has come from climate models of varying complexity that show transitions to SBE states and undergo hysteresis under changes in solar radiation. In this paper, we apply large-scale bifurcation analyses to a novel, fully-implicit Earth System Model of Intermediate Complexity (I-EMIC) to study SBE transitions. The I-EMIC contains a primitive equation ocean model, a model for atmospheric heat and moisture transport, a sea ice component and formulations for the adjustment of albedo over snow and ice. With the I-EMIC, high-dimensional branches of the SBE bifurcation diagram are obtained through parameter continuation. We are able to identify stable and unstable equilibria and uncover an intricate bifurcation structure associated with the ice-albedo feedback. Moreover, large-scale linear stability analyses are performed near major bifurcations, revealing the spatial nature of destabilizing perturbations.
MULTIFRACTAL ANALYSIS WITH DETRENDING WEIGHTED AVERAGE ALGORITHM OF HISTORICAL VOLATILITY
Authors: WANG JIAN , SHAO WEI
Published: May 2021

In this paper, we develop the multifractal detrending weighted average algorithm of historical volatility (MF-DHV) for one-dimensional multifractal measure based on the classical multifractal detrended fluctuation analysis (MF-DFA). In the calculation process of getting a local trend for MF-DHV, historical volatility is taken to develop an moving average algorithm, which is different from the simple moving average function in multifractal detrended moving average (MF-DMA). We assess the performance of three methods such as MF-DFA, MF-DMA, and MF-DHV based on the p-model multiplicative cascading constructed time series. The computational results show that all the estimated generalized Hurst exponent [Formula: see text], the scaling exponent [Formula: see text], and the singularity spectrum [Formula: see text] of MF-DHV are in good agreement with the theoretical values. In addition, we also calculate the standard deviations of [Formula: see text] and [Formula: see text] for three methods, and the lowest errors in MF-DHV provides the most accurate estimates. To avoid the accidental selection of parameters, we change the total length of the generated multifractal simulation data and p-value, respectively. It is found that in all the cases, the MF-DHV outperforms the other two methods.
Frame of translates and its canonical dual in L2(G)
Authors: Saadan Majid Jabbar , Janfada Mohammad , Kamyabi-Gol Radjab Ali
Published: May 2021

Let [Formula: see text] be a locally compact group. This work aims to study some important properties of the frame of translates for the space [Formula: see text]. Also, we showed that the frame of translates can be a frame for a proper subspace of [Formula: see text], in the case that [Formula: see text] has a contractive automorphism. Furthermore, we characterize the frame properties for such systems and find an expression for the canonical dual frame.
BOPYIN-anil and BOPYIN-boranil complex: Synthesis, spectroscopic properties and ESIPT process
Authors: Su Peng , Hu Yanjun , Yuan Xiaohui , Hu Cong , Liu Debao , Zhang Nuonuo , Yan Jiaying
Published: May 2021

Two BOPYIN dyes (W-1 and W-2) were synthesized, and their structural and photophysical properties were investigated. The absorption bands of both dyes located at ca. 350 and 500 nm in diverse solvents. The absorption profiles are a linear combination of those of the BOPYIN core and the boranil or anil subunits. Their emission spectra were observed at ca. 565 and 540 nm with 14.2% and 77% quantum yield in CHCl3, respectively. The absorption, excitation and emission spectra for both dyes confirm that the boranil or anil moieties could be used as an input energy antenna for cascade energy transfer to the fluorescent BOPYIN residue at 540 nm. Subsequently, ESIPT process of W-1 is fast and more likely to occur in non-polar solvent investigated by DFT calculation.
An elementary linear-algebraic proof without computer-aided arguments for the group law on elliptic curves
Authors: Nuida Koji
Published: May 2021

The group structure on the rational points of elliptic curves plays several important roles, in mathematics and recently also in other areas such as cryptography. However, the famous proofs for the group property (in particular, for its associative law) require somewhat advanced mathematics and therefore are not easily accessible by non-mathematician. On the other hand, there have been attempts in the literature to give an elementary proof, but those rely on computer-aided calculation for some part in their proofs. In this paper, we give a self-contained proof of the associative law for this operation, assuming mathematical knowledge only at the level of basic linear algebra and not requiring computer-aided arguments.
Penalty- and Locality-aware Memory Allocation in Redis Using Enhanced AET
Authors: Pan Cheng , Wang Xiaolin , Luo Yingwei , Wang Zhenlin
Published: May 2021

Due to large data volume and low latency requirements of modern web services, the use of an in-memory key-value (KV) cache often becomes an inevitable choice (e.g., Redis and Memcached). The in-memory cache holds hot data, reduces request latency, and alleviates the load on background databases. Inheriting from the traditional hardware cache design, many existing KV cache systems still use recency-based cache replacement algorithms, e.g., least recently used or its approximations. However, the diversity of miss penalty distinguishes a KV cache from a hardware cache. Inadequate consideration of penalty can substantially compromise space utilization and request service time. KV accesses also demonstrate locality, which needs to be coordinated with miss penalty to guide cache management.

In this article, we first discuss how to enhance the existing cache model, the Average Eviction Time model, so that it can adapt to modeling a KV cache. After that, we apply the model to Redis and propose pRedis,
Penalty- and Locality-aware Memory Allocation
in Redis, which synthesizes data locality and miss penalty, in a quantitative manner, to guide memory allocation and replacement in Redis. At the same time, we also explore the diurnal behavior of a KV store and exploit long-term reuse. We replace the original passive eviction mechanism with an automatic dump/load mechanism, to smooth the transition between access peaks and valleys. Our evaluation shows that pRedis effectively reduces the average and tail access latency with minimal time and space overhead. For both real-world and synthetic workloads, our approach delivers an average of 14.0%∼52.3% latency reduction over a state-of-the-art penalty-aware cache management scheme, Hyperbolic Caching (HC), and shows more quantitative predictability of performance. Moreover, we can obtain even lower average latency (1.1%∼5.5%) when dynamically switching policies between pRedis and HC.
Impact of Nickel Ions on the Oxygen Reduction Reaction Kinetics of Pt and on Oxygen Diffusion through Ionomer Thin Films
Authors: Kariuki Nancy N. , Myers Deborah J.
Published: May 2021

The effects of dissolved nickel on the oxygen reduction reaction (ORR) kinetics and oxygen transport properties of perfluorosulfonic acid (PFSA) thin films were investigated using rotating disk electrode (RDE) measurements of ORR on a PFSA-coated platinum electrode. The electrochemical characterization in 0.1 M perchloric acid (HClO4) with and without added Ni2+ quantitatively measured the impact of ionic interactions between the Ni2+ cations and sulfonate (SO3
−) anions on oxygen transport through the PFSA thin film. Cyclic voltammetry (CV) curves in deaerated electrolyte showed that Ni2+ cations diffusing through the PFSA thin film interact with the Pt surface altering the hydrogen underpotential deposition and stripping processes and decreasing ORR kinetics. The RDE limiting current results point to reduced permeability of oxygen through PFSA-Ni2+ compared to PFSA-H+. The results indicate that transition metals leached from Pt alloy catalyst may be detrimental not only to the intrinsic ORR kinetics of the PEFC cathode catalyst through loss of the ORR-enhancing transition metal, but may also inhibit the diffusion of oxygen to the catalytic sites and poison the ORR.
Review—Atomic Layer Deposition of Silicon Dioxide Thin Films
Authors: Vasilyev Vladislav Yu.
Published: May 2021

This article provides a critical review of published experimental data for silicon dioxide thin films deposited using cyclic technologies, including thermally-activated (TA) and plasma-enhanced (PE) Atomic Layer Deposition (ALD). The studied precursors (cyanates, silicon chlorides, oxygen-containing reactants, amino silanes and heterocyclic compounds) have been analyzed historically with a search depth of about 25 years. The focus is on the aspects of film growth. The aminosilane precursor group has been comprehensively analyzed for the TA-ALD and PE-ALD processes using ozone and oxygen as oxidants, respectively. The deposition rates are on the level of 0.05–0.15 nm per process cycle on average. The deposition rate of PE-ALD shows gradual decrease with temperature for all investigated precursors. For TA-ALD processes, the deposition temperature decreases and the deposition rates increase with a decrease in the number of amino groups in the silane molecule, and with an increase in the ozone dose. Problems and solutions to the problem of thin film conformality in ALD processes are analyzed. Assumptions are made about the possible prospects for investigating TA-ALD processes using monosilane, oxygen and nitrous oxide at low deposition temperatures.
Impaired right and left ventricular function and relaxation induced by pulmonary regurgitation are not reversed by tardive antifibrosis treatment
Authors: Akazawa Yohei , Fujioka Tao , Ide Haruki , Yazaki Kana , Honjo Osami , Sun Mei , Friedberg Mark K.
Published: May 2021

The time-course of RV dilatation and the mechanisms of biventricular dysfunction caused by PR have not been well characterized and the effect of losartan in volume-overloaded RV remains controversial. Our findings suggest that severe PR induces early onset of RV dilatation and dysfunction with little progression after the first 4 wk. The RV dilatation distorts LV geometry with associated impaired LV relaxation. Losartan reduced RV fibrosis but did not reverse RV dilatation and dysfunction.
Artificial Intelligence and Medical Internet of Things Framework for Diagnosis of Coronavirus Suspected Cases
Authors: Iskanderani Ahmed I. , Mehedi Ibrahim M. , Aljohani Abdulah Jeza , Shorfuzzaman Mohammad , Akther Farzana , Palaniswamy Thangam , Latif Shaikh Abdul , Latif Abdul , Alam Aftab
Published: May 2021

The world has been facing the COVID-19 pandemic since December 2019. Timely and efficient diagnosis of COVID-19 suspected patients plays a significant role in medical treatment. The deep transfer learning-based automated COVID-19 diagnosis on chest X-ray is required to counter the COVID-19 outbreak. This work proposes a real-time Internet of Things (IoT) framework for early diagnosis of suspected COVID-19 patients by using ensemble deep transfer learning. The proposed framework offers real-time communication and diagnosis of COVID-19 suspected cases. The proposed IoT framework ensembles four deep learning models such as InceptionResNetV2, ResNet152V2, VGG16, and DenseNet201. The medical sensors are utilized to obtain the chest X-ray modalities and diagnose the infection by using the deep ensemble model stored on the cloud server. The proposed deep ensemble model is compared with six well-known transfer learning models over the chest X-ray dataset. Comparative analysis revealed that the proposed model can help radiologists to efficiently and timely diagnose the COVID-19 suspected patients.
Giant Cell Reparative Granuloma of the Orbit: Clinicopathological Characteristics and Treatment
Authors: Bengoa-González Álvaro , Mencía-Gutiérrez Enrique , Alonso-Martín Beatriz , Laslău Bianca-Maria , Salvador Elena , Enguita-Valls Ana-Belén , Lago-Llinás María-Dolores
Published: May 2021

Giant cell reparative granuloma (GCRG) is a rare fibroosseous lesion uncommonly seen in the orbital area. Although benign, it is known to be recurrent and locally destructive. We report two cases of GCRG of the orbit. In both cases, computed tomography revealed a heterogeneously growing well-defined mass, arising from the roof of the orbit, affecting the cortex, and invading the orbit. In the first case, the mass extended into the anterior cranial fossa. Magnetic resonance imaging with gadolinium showed, in both cases, a cystic character of the lesion with fluid levels. The surgical treatment was performed via an upper crease incision. An ultrasonic aspirator system was used to remove the tumor tissue and its extension into cranial fossa. Careful histopathologic analysis established the diagnosis of GCRG. Symptoms resolved completely with no evidence of recurrence after a follow-up of 18 and 14 months, respectively. We present the clinicopathological and radiological findings, and we describe the surgical approach. As a rare entity, GCRG of the orbit should be considered in differential diagnosis of fibroosseous orbital masses. Complete surgical excision carries a low risk of recurrence.
Deep Personalized Medical Recommendations Based on the Integration of Rating Features and Review Sentiment Analysis
Authors: Zhou Qihang , Su Lei , Wu Liping , Jiang Di
Published: May 2021

To comply with the rapid development of big data in mobile services, an increasing number of websites have begun to provide users with recommendation decisions in various areas, like shopping, tourism, food, and medical treatment. However, there are still some challenges in the field of medical recommendation systems, such as the lack of personalized medical recommendations and the problem of data sparseness, which seriously restricts the effectiveness of such recommendations. In this paper, we propose a personalized medical recommendation method based on a convolutional neural network that integrates revised ratings and review text, called revised rating and review based on a convolutional neural network (RR&R‐CNN). First, the review text is divided into user and doctor datasets, and BERT vectorized representations are performed on them. Moreover, the original rating features are revised by adding the sentiment analysis values of the review text. Then, the vectorized review text and the revised rating features are spliced together and input into the convolutional neural network to extract the deep nonlinear feature vectors of both users and doctors. Finally, we use a factorization machine for feature interaction. We conduct comparison experiments based on a Yelp dataset in the “Health & Medical” category. The experimental results confirm the conclusion that RR&R‐CNN has a better effect compared to a traditional method.
Big Data-Enabled Analysis of Factors Affecting Patient Waiting Time in the Nephrology Department of a Large Tertiary Hospital
Authors: Li Jialing , Zhu Guiju , Luo Li , Shen Wenwu
Published: May 2021

The length of waiting time has become an important indicator of the efficiency of medical services and the quality of medical care. Lengthy waiting times for patients will inevitably affect their mood and reduce satisfaction. For patients who are in urgent need of hospitalization, delayed admission often leads to exacerbation of the patient’s condition and may threaten the patient’s life. We gathered patients’ information about outpatient visits and hospital admissions in the Nephrology Department of a large tertiary hospital in western China from January 1st, 2014, to December 31st, 2016, and we used big data-enabled analysis methods, including univariate analysis and multivariate linear regression models, to explore the factors affecting waiting time. We found that gender (P=0.048), the day of issuing the admission card (Saturday,P=0.028), the applied period for admission (P<0.001), and the registration interval (P<0.001) were positive influencing factors of patients’ waiting time. Disease type (after kidney transplantation,P<0.001), number of diagnoses (P=0.037), and the day of issuing the admission card (Sunday,P=0.001) were negative factors. A linear regression model built using these data performed well in the identification of factors affecting the waiting time of patients in the Nephrology Department. These results can be extended to other departments and could be valuable for improving patient satisfaction and hospital service quality by identifying the factors affecting waiting time.
Hypoxia Induced by Cobalt Chloride Triggers Autophagic Apoptosis of Human and Mouse Drug‐Resistant Glioblastoma Cells through Targeting the PI3K‐AKT‐mTOR Signaling Pathway
Authors: Lee Yuan-Wen , Cherng Yih-Giun , Yang Shun-Tai , Liu Shing-Hwa , Chen Ta-Liang , Chen Ruei-Ming
Published: May 2021

Glioblastoma multiforme (GBM) is the most aggressive brain tumor. Drug resistance mainly drives GBM patients to poor prognoses because drug‐resistant glioblastoma cells highly defend against apoptotic insults. This study was designed to evaluate the effects of cobalt chloride (CoCl2) on hypoxic stress, autophagy, and resulting apoptosis of human and mouse drug‐resistant glioblastoma cells. Treatment of drug‐resistant glioblastoma cells with CoCl2 increased levels of hypoxia‐inducible factor‐ (HIF‐) 1α and triggered hypoxic stress. In parallel, the CoCl2‐induced hypoxia decreased mitochondrial ATP synthesis, cell proliferation, and survival in chemoresistant glioblastoma cells. Interestingly, CoCl2 elevated the ratio of light chain (LC)3‐II over LC3‐I in TMZ‐resistant glioblastoma cells and subsequently induced cell autophagy. Analyses by loss‐ and gain‐of‐function strategies further confirmed the effects of the CoCl2‐induced hypoxia on autophagy of drug‐resistant glioblastoma cells. Furthermore, knocking down HIF‐1α concurrently lessened CoCl2‐induced cell autophagy. As to the mechanisms, the CoCl2‐induced hypoxia decreased levels of phosphoinositide 3‐kinase (PI3K) and successive phosphorylations of AKT and mammalian target of rapamycin (mTOR) in TMZ‐resistant glioblastoma cells. Interestingly, long‐term exposure of human chemoresistant glioblastoma cells to CoCl2 sequentially triggered activation of caspases‐3 and ‐6, DNA fragmentation, and cell apoptosis. However, pretreatment with 3‐methyladenine, an inhibitor of autophagy, significantly attenuated the CoCl2‐induced autophagy and subsequent apoptotic insults. Taken together, this study showed that long‐term treatment with CoCl2 can induce hypoxia and subsequent autophagic apoptosis of drug‐resistant glioblastoma cells via targeting the PI3K‐AKT‐mTOR pathway. Thus, combined with traditional prescriptions, CoCl2‐induced autophagic apoptosis can be clinically applied as a de novo strategy for therapy of drug‐resistant GBM patients.
Fast Monocular Visual‐Inertial Initialization with an Improved Iterative Strategy
Authors: Cheng Jun , Zhang Liyan , Chen Qihong
Published: May 2021

The initialization process has a great effect on the performance of the monocular visual inertial simultaneous localization and mapping (VI‐SLAM) system. The initial estimation is usually solved by least squares such as the Gauss‐Newton (G‐N) algorithm, but the large iteration increment might lead to the slow convergence or even divergence. In order to solve this problem, an improved iterative strategy for initial estimation is proposed. The methodology of our initialization can be divided into four steps: Firstly, the pure visual ORB‐SLAM model is utilized to make all variables observable. Secondly, the IMU preintegration technology is adopted for IMU‐camera frequency alignment at the same time with key frame generation. Thirdly, an improved iterative strategy which is based on the trust region is introduced for the gyroscope bias estimation as well as the gravity direction is refined. Finally, the accelerometer bias and visual scale are estimated on the basis of previous estimations. Experimental results on the public datasets show that the estimation of initial values can be converged faster, as well as the velocity and pose of sensor suite can be estimated more accurately than the original method.
Effect of Root Dentin Pretreatment on Micro-Push-Out Bond Strength of Fiber Posts to Root Canal Dentin: Cold Atmospheric Argon Plasma (CAAP) and Ethylenediaminetetraacetic Acid (EDTA)
Authors: Sadeghi Mahounak Farzaneh , Abbasi Mahdi , Meraji Naghmeh , Rezazadeh Sefideh Maryam , Kharrazi Fard Mohammad Javad , Ahmadi Elham , Ranjbar Omrani Ladan
Published: May 2021

Purpose. Debonding from the root canal dentin is the most common failure mode of fiber posts. This study aimed to assess the effects of cold atmospheric argon plasma (CAAP) and ethylenediaminetetraacetic acid (EDTA) on micro-push-out bond strength of fiber posts to root canal dentin. Materials and Methods. Forty maxillary canine teeth were decoronated, underwent endodontic treatment, and were stored in an incubator for 7 days. After post space preparation, the teeth were randomly divided into four groups for different surface treatments: (I) saline, (II) 17% EDTA, (III) CAAP, and (IV) 17% EDTA + CAAP. Fiber posts (Whitepost no. 2, FGM) were cemented into the root canals using Panavia F2.0 resin cement, and 1 mm-thick sections were made at the coronal, middle, and apical thirds of the roots. The samples underwent micro-push-out bond strength test. The mode of failure was also determined under a stereomicroscope. Data were analyzed using three-way ANOVA and Tukey’s post hoc test (α = 0.05). The mode of failure data were analyzed using the chi-square test. Results. The mean micro-push-out bond strength of fiber posts was not significantly different in the four groups (P>0.05). However, the bond strength values in the coronal third were significantly higher than the corresponding values in the apical third (P=0.01). There was no significant difference in the modes of failure between the groups (P>0.05). Conclusion. Application of CAAP alone or in combination with 17% EDTA could not successfully increase the bond strength of fiber posts to root canal dentin.
Provably Secure Security-Enhanced Timed-Release Encryption in the Random Oracle Model
Authors: Yuan Ke , Wang Yahui , Zeng Yingming , Ouyang Wenlei , Li Zheng , Jia Chunfu
Published: May 2021

Cryptographic primitive of timed-release encryption (TRE) enables the sender to encrypt a message which only allows the designated receiver to decrypt after a designated time. Combined with other encryption technologies, TRE technology is applied to a variety of scenarios, including regularly posting on the social network and online sealed bidding. Nowadays, in order to control the decryption time while maintaining anonymity of user identities, most TRE solutions adopt a noninteractive time server mode to periodically broadcast time trapdoors, but because these time trapdoors are generated with fixed time server’s private key, many “ciphertexts” related to the time server’s private key that can be cryptanalyzed are generated, which poses a big challenge to the confidentiality of the time server’s private key. To work this out, we propose a concrete scheme and a generic scheme of security-enhanced TRE (SETRE) in the random oracle model. In our SETRE schemes, we use fixed and variable random numbers together as the time server’s private key to generate the time trapdoors. We formalize the definition of SETRE and give a provably secure concrete construction of SETRE. According to our experiment, the concrete scheme we proposed reduces the computational cost by about 10.8% compared to the most efficient solution in the random oracle model but only increases the almost negligible storage space. Meanwhile, it realizes one-time pad for the time trapdoor. To a large extent, this increases the security of the time server’s private key. Therefore, our work enhances the security and efficiency of the TRE.