bluuebunny/crossref_metadata_2025 huggingface dataset:
Novel mycorrhizal cheating in a green orchid: Cremastraappendiculata depends on carbon from deadwood through fungal associations
Authors: Suetsugu Kenji , Haraguchi Takashi F. , Tayasu Ichiro
Published: April 2021

To date, there has been no robust evidence for the exploitation of saprotrophic non‐rhizoctonia fungi by green plants, although some fully mycoheterotrophic orchids are known to exploit them, and mycoheterotrophic evolution has probably occurred through intermediate mixotrophic stages.

We investigated the physiological ecology of a fully mycoheterotrophic species Cremastra aphylla and its photosynthetic sister species Cremastra appendiculata, which putatively exploit saprotrophic fungi. Their mycorrhizal partners and ultimate nutritional sources were determined using molecular, stable isotopic, and radiocarbon analysis.

Both Cremastra aphylla and Cremastra appendiculata were consistently associated with wood‐decaying Psathyrellaceae. In addition, both species were highly enriched in carbon‐13 (13C) and, to a less degree, in nitrogen‐15 (15N). The δ13C and δ15N values of Cremastra appendiculata were intermediate between those of Cremastra aphylla and those of autotrophic plants. All Cremastra appendiculata samples and two Cremastra aphylla samples exhibited elevated Δ14C values due to the acquisition of carbon fixed in wood during the past decades (14C‐enriched bomb carbon).

Our multifaceted evidence indicated that both species obtained carbon from deadwood via saprotrophic fungi. Our findings strongly suggest that mixotrophic relationships associated with wood‐decaying fungi represent a novel evolutionary pathway for full mycoheterotrophy in orchids.
Retrospective analysis of referrals to the North East of England intermediate oral surgery service
Authors: Webster James , Landes David
Published: April 2021

Introduction

The intermediate oral surgery service in North East England was introduced in 2009 following changes in the primary care contract in 2005 allowing primary care organisations to locally commission services to meet population need. The aim of this service introduction was to reduce pressures on secondary care and improve efficiency and costs of oral surgery service provision. Where there are geographical variations in the number of referrals received to intermediate oral surgery services in North East England, this study aimed to identify the reasons for these.

Materials and methods

A retrospective analysis of referrals to the National Health Service (NHS) Intermediate North East of England Oral Surgery Service was completed. Analysis of 48,286 referrals from 2009 to 2019 was assessed from two NHS specialist oral surgery providers. Primary care practice referrals were located to practice postcode; the sum of referrals from each postcode accumulated over this period. Referral variations were compared with NHS primary care contract sizes, distance to specialist provider and Index of Multiple Deprivation of provider location to identify correlations.

Results

Data indicate a significant range in primary care referral frequency over the 10‐year period. Referrals from primary care providers ranged from 1 to 2334 over the 10‐year period. No correlation is seen between distance to provider (r2 = 0.058), contract size (r2 = 0.087), deprivation levels (r2 = 0.01) and the referral rate.

Conclusion

The large variation in referral rate provides data for commissioners of dental services including managed clinical networks (MCNs) to outline high referring primary care practices and plan for future service development.
The effect of dexmedetomidine premedication on postoperative systemic inflammatory response in children undergoing hernia repair surgery: A randomized controlled trial
Authors: Du Zhen , Wei Si‐Wei , Zhang Xi‐Ying , Xiang Zhen , Qu Shuang‐Quan
Published: April 2021

Background

Surgery results in systemic inflammation, which can affect the central nervous system, leading to changes in mood, emotion, and behavior. Our previous study has shown that compared to midazolam, dexmedetomidine premedication effectively decreased children's postoperative anxiety.

Aim

To investigate whether dexmedetomidine infusion before hernia repair alleviates postoperative systemic inflammation in children and whether postoperative anxiety may be associated with postoperative inflammation.

Methods

This prospective double‐blind randomized controlled trial was conducted in 120 children scheduled to undergo elective hernia repair. Before anesthesia induction, all children received an intravenous infusion consisted of dexmedetomidine (n = 40; 0.5 µg/g, group D), midazolam (n = 40; 0.08 mg/kg, group M), or normal saline (n = 40; group C). One‐way ANOVA with least significant difference multiple comparison test was used for multigroup comparisons of postoperative plasma levels of inflammatory cytokines and m‐YPAS scores. Spearman rank correlation tests were used for analyzing m‐YPAS scores with postoperative plasma levels of inflammatory cytokines.

Results

Plasma levels of tumor necrosis factor‐alpha (7.0 ± 1.6 vs. 8.1 ± 1.6, mean difference [95% CI]: 1.19 [0.26–2.11], p = .008) (pg/ml) and of interleukin‐6 (1.8 ± 1.2 vs. 3.3 ± 1.6, mean difference [95% CI]: 1.49 [0.74–2.25], p < .001) (pg/ml) and neutrophils‐to‐lymphocyte ratio (1.0 ± 0.5 vs. 1.5 ± 0.7, mean difference [95% CI]: 0.48 [0.17–0.78], p < .001) were significantly lower in group D than in group C. Furthermore, compared to group M, group D showed significantly lower plasma tumor necrosis factor‐alpha levels (7.0 ± 1.6 vs. 7.9 ± 1.9, mean difference [95% CI]: 0.96 [0.04–1.88], p = .04) (pg/ml) and interleukin‐6 levels (1.8 ± 1.2 vs. 2.9 ± 1.5, mean difference [95% CI]: 1.06 [0.31–1.81], p = .004) (pg/ml), and neutrophil‐to‐lymphocyte ratio (1.0 ± 0.5 vs. 1.5 ± 0.6, mean difference [95% CI]: 0.42 [0.11–0.72], p = .004). Anxiety scores at postoperative 2 and 4 h in the three groups positively correlated with plasma levels of proinflammatory cytokines.

Conclusion

A single preoperative intravenous dexmedetomidine dose in children undergoing same‐day surgery reduces postoperative systemic inflammation.
Cerebral hemoglobin oxygenation in children with congenital heart disease
Authors: Terada Kazuya , Nakamura Shinji , Nakao Yasuhiro , Fukudome Keisuke , Miyagi Yuichi , Onishi Tatsuya , Kusaka Takashi
Published: April 2021

Background

It is important to identify the pathological characteristics of cerebral circulation and oxygen metabolism at the bedside in children with congenital heart disease (CHD) to prevent neurodevelopmental impairments. The brain regional oxygen saturation index (rSO2) can be easily obtained at the bedside with near‐infrared spectroscopy and has been widely used in the management of children with CHD in recent years.

Methods

To determine if the rSO2 before or after CHD surgery is a good predictor of cerebral oxygen metabolism, we investigated the impact of different clinical variables on the correlation between rSO2 and reference values under steady ratios of hemoglobin oxygen saturation in the internal jugular vein (SjvO2) or femoral artery (SaO2) (0.75:0.25, 0.66:0.34, and 0.50:0.50) in 186 children with CHD undergoing cardiac catheterization.

Results

In three patient groups—double ventricles before surgery, double ventricles after surgery, and single ventricle before surgery—there were significant relationships between rSO2 and the reference values of SO2 under all three steady ratios of SjvO2 and SaO2. No relationship with the reference values was found for the single ventricle after surgery group.

Conclusions

Regional oxygen saturation index is useful for assessing cerebral oxygenation in children with CHD, but knowledge of the underlying cardiac pathology in CHD, especially in the case of a single ventricle after surgery, is important for the correct interpretation of rSO2 measurements obtained using near‐infrared spectroscopy.
Mental fatigue measurement using eye metrics: A systematic literature review
Authors: Bafna Tanya , Hansen John Paulin
Published: April 2021

Mental fatigue measurement techniques utilize one or a combination of the cognitive, affective, and behavioral responses of the body. Eye‐tracking and electrooculography, which are used to compute eye‐based features, have gained momentum with increases in accuracy and robustness of the lightweight equipment emerging in the markets and can be used for objective and continuous assessment of mental fatigue. The main goal of this systematic review was to summarize the various eye‐based features that have been used to measure mental fatigue and explore the relation of eye‐based features to mental fatigue. The review process, following the preferred reporting items for systematic reviews and meta‐analyses, used the electronic databases Web of Science, Scopus, ACM digital library, IEEE Xplore, and PubMed. Of the 1,385 retrieved documents, 34 studies met the inclusion criteria, resulting in 21 useful eye‐based features. Categorizing these into eight groups revealed saccades as the most promising category, with saccade mean and peak velocity providing quick access to the cognitive states within 30 min of fatiguing activity. Complex brain networks involving sympathetic and parasympathetic nervous systems control the relation of mental fatigue to tonic pupil size and have the potential to indicate mental fatigue in controlled experimental conditions. Other categories, like blinks, are derived from the field of sleep research and should be used with caution. Several limitations emerged in the analysis, including varied experimental methods, use of dim lighting during the experiment (that could possibly also induce sleepiness), and use of unclear data analysis techniques, thereby complicating comparisons between studies.
CT myelographic diagnosis of ligamentum flavum hypertrophy in a Warmblood Gelding with progressive ataxia
Authors: Hellige Maren , Warnken Tobias , Puff Christina , Feige Karsten
Published: April 2021

An 8‐year‐old Warmblood gelding presented with a history of progressive ataxia for 6 weeks. Intra‐ and intervertebral ratios measured from lateral radiographs of the cervical spine were within normal limits. Computed tomographic myelography of the cervical spine revealed focal compression of the dorsal and the ventral contrast column as well as a ventral displacement of the spinal cord within the spinal canal due to a bulging of soft tissue attenuating material in the dorsal half of the intervertebral junction of C6 and C7. Post‐mortem histopathological examination confirmed chondroid metaplasia of the ligamentum flavum at C6‐C7.
Vertebral heart score to evaluate cardiac size in thoracic radiographs of 124 healthy rats (Rattus norvegicus)
Authors: Dias Sara , Anselmi Carlo , Espada Yvonne , Martorell Jaume
Published: April 2021

Dilated cardiomyopathy is a relatively common disease in pet rats (Rattus norvegicus); however, there is a lack of radiographic references for the normal cardiac size in this species. The aim of this prospective, anatomical and reference interval study was to establish quantitative radiographic reference range measurements for the vertebral heart score (VHS) in rats. Right lateral (RL), ventrodorsal (VD), and dorsoventral (DV) radiographs of clinically healthy rats (n = 124) were evaluated. Measurements were performed by 2 expert readers who were unaware of signalment data. The mean values and references intervals of VHS were 7.7 and 7.0–8.5 for the RL, 7.5 and 6.6–8.6 for the VD, and 7.9 and 6.9–9.0 for the DV, with VHS values greater in males than in females. The measurements reported in this study can be used by the clinician as an objective tool to evaluate cardiac size in rats, in order to improve the diagnosis and treatment of cardiac diseases.
A double‐edged sword: Unrecognized cryptic diversity and taxonomic impediment in Eois (Lepidoptera, Geometridae)
Authors: Moraes Simeão de Souza , Murillo‐Ramos Leidys , Machado Patrícia A. , Ghanavi Hamid R. , Magaldi Luiza M. , Silva‐Brandão Karina L. , Kato Massuo J. , Freitas André V. L. , Wahlberg Niklas
Published: April 2021

The genus Eois Hübner (Geometridae: Larentiinae) comprises 254 valid species. Being a hyperdiverse genus, Eois potentially includes many undescribed cryptic species and embodies a problematic taxonomic scenario. The actual diversity of Eois is greatly underestimated and the Neotropical fauna needs to be well known since it figures as one of the most threatened terrestrial ecosystem. In the present study, we compare three species delimitation methods to highlight the hidden diversity within a subset of Eois species: Automatic Barcode Gap Discovery, Bayesian Poisson Tree Processes and Multi‐Rate Poisson Tree Processes. Our results point to an increase up to 176% in the currently valid species number. The hypothesis of cryptic diversity is corroborated by morphological characters within some species complexes. For complexes comprising species of Brazilian fauna, we provide a preliminary taxonomic assessment. Additionally, we found no congruence among the three delimitation methods for some species complexes, which indicates the importance of species and locality sampling as well as the previous alpha taxonomic knowledge in avoiding result bias. In this sense, we tried to standardize the identification provided for the Genbank sequences used in most relevant publications for Eois, in order to minimize biases and maximize the replicability of analyses in future studies. Moreover, we stress the importance of an integrative taxonomic approach for cryptic species discovery approach by employing both morphological attributes and life history to corroborate molecular analysis.
Thermal Effects in Calendering Viscous Fluids
Authors: Finston M.
Published: April 2021

Calendering (rolling) of plastics at high speeds produces blistering and peeling which are attributed to a combination of uneven temperature distribution, and effect of temperature on the physical properties of the material. In this paper the problem is examined by studying the calendering of a viscous liquid in some detail. It is shown that a thermal boundary-layer effect exists of such magnitude as to account for formation of blisters. An example is given using typical calendering dimensions and physical properties of a plastic, which yields a thermal boundary-layer thickness of the order of depth of the blisters as observed. These data furnish further qualitative confirmation to the physical argument.
The Dynamics of the Buckling of Elastic Columns
Authors: Hoff N. J.
Published: April 2021

The motion of a perfectly elastic initially slightly curved column is calculated when one of its ends is displaced axially at a constant speed in a perfectly rigid testing machine. A nondimensional quantity Ω is defined which depends only upon the slenderness ratio of the column and the ratio of the velocity of the propagation of sound in its material to the speed of the testing machine. Two elastic columns are dynamically similar if Ω and the initial deviations from straightness are the same for both of them. The dynamic transverse deflections of the column lag behind the static values at the outset and overshoot them later. At an advanced stage of the loading the dynamic deflections can be represented as oscillations superimposed upon the static deflections. The axial compressive force in the column increases proportionately to the displacement of the loading head of the testing machine in the first phase of the loading. When the deflections become large, the compressive force increases at a reduced rate, reaches a maximum, and finally begins to oscillate about the Euler load. The maximum force recorded on the testing machine can be a multiple of the Euler load when Ω and the initial deviations from straightness are small. At ordinary speeds and with the usual inaccuracies of routine testing the maximum load should differ little from the Euler load.
Approximate Approach for Torsion Problem of a Shaft With a Circumferential Notch
Authors: Ōkubo H.
Published: April 2021

The torsion problem of a bar with varying circular section has been treated by several investigators over a long period. Usually, the solution covering all points in a shaft is found first and then the maximum stress is obtained. Accordingly, the analysis usually becomes complicated and so only few cases have been treated completely. It is essential from the technical point of view, however, to find the stresses around a notch rather than the stresses at every point in a shaft. The approach employed in this paper is somewhat different from others, and the approximate values for the stresses on the surface of a shaft are found directly without solving the problem completely.
Statistical Design of Fatigue Experiments
Authors: Weibull Waloddi
Published: April 2021

An analytical expression connecting fatigue lives with applied stresses, and methods for computing the values of its parameters from experimental data are given. Formulas for estimating the uncertainty of computed parameter values, caused by scatter of loads and fatigue lives, for optimum distribution of specimens, and for optimum choice of stress levels, are deduced. Testing time and costs may be reduced by more than 40 per cent by using the formulas.
The Marcus Method Applied to Solution of Uniformly Loaded and Clamped Rectangular Plate Subjected to Forces in Its Plane
Authors: Chang C. C. , Conway H. D.
Published: April 2021

This paper presents a solution to the small-deflection problem of the uniformly loaded rectangular plate with all edges clamped, when the latter are subjected to uniform tensile or compressive forces in the plane of the plate. Since an exact solution to the problem is hardly possible, the Marcus method was used for the approximate solution of the biharmonic equation, subject to the conditions of zero slope and deflection at the boundary. Deflections and moments are presented for a square plate with four particular values of tensile end load, and for the rectangular plate with seven length-breadth ratios and with one value of compressive end load.
Plastic Flow in a V-Notched Bar Pulled in Tension
Authors: Lee E. H.
Published: April 2021

A V-notched bar pulled in tension in plane strain as shown in Fig. 1 is considered. The distribution of stress and deformation are determined from the analysis of the motion with large strains as the initial notch width pulls down toward line contact as the test proceeds. The analysis is based upon the theory of flow of a so-called Saint Venant-Mises material, which flows at a constant yield limit given by the Mises criterion, and obeys the Mises flow-type relationship between stress and strain increments. The successive configurations of an initially square grid on the cross section of the notch are obtained to illustrate the strain distribution. This solution is of interest in investigating the initiation of fracture in a notch-bar tension test. In such a test the foregoing type of solution applies until plastic flow is arrested by the appearance of a fracture crack. The variation of the solution with notch angle is of interest in connection with the determination of the technical cohesive strength of a metal using Kuntze’s technique. The present solution indicates a contrast with Kuntze’s hypothesis, in that it predicts the possibility of a plastic-flow type of rupture at a stress depending only upon the yield stress of the metal.
Thermal Stresses in Bodies Exhibiting Temperature-Dependent Elastic Properties
Authors: Hilton H. H.
Published: April 2021

Expressions are derived for thermal stresses and strains due to a steady-state temperature gradient in a thick-walled cylinder and a circular thin plate, made of a material having temperature-dependent elastic properties. Two numerical examples are computed for specific temperature gradients and temperature-dependent elastic properties, which yield results showing that the maximum thermal stresses are appreciably lower and the maximum thermal strains are larger than the corresponding values obtained for temperature-independent properties. The validity of the thermal plane-stress assumptions is investigated and it is shown that such solutions, regardless of whether the material properties are temperature-dependent or constant, are only approximations. The smaller the temperature gradient the more closely are the plane-stress assumptions satisfied.
A Matrix Method for Flexibility Analysis of Piping Systems
Authors: Brock J. E.
Published: April 2021

By use of matrix algebra a concise and strongly motivated method is developed for analyzing flexibility of piping systems. The method is particularly suited for systems which are complicated by multiple branches, additional constraints, inconvenient orientations, and so on, as well as for examination and modification for particular purposes of more widely known methods.
Correlation Between Friction Coefficient and Friction Vibration in Running-In Process Based on Cross Recurrence Plots
Authors: Zhou Yuankai , Peng Minglong , Zuo Xue , Xu Jing
Published: April 2021

The friction coefficient is difficult to measure in a real application, whether friction coefficient and vibration signals have the same dynamic characteristics is an urgent issue to be solved. The running-in friction tests were carried out under dry friction, starved, and flooded lubrications. Cross recurrence plots (CRPs) and their measures were used to explore the correlation between friction signals. The results show that the more obvious the diagonal structures in CRPs, the better the correlation between the two signals. The measures from different friction systems are smaller than those from the same system. Average diagonal length is more sensitive to characterize the correlation. Irrespective of lubrication conditions, friction coefficient and vibration in the same friction system have a strong correlation. The correlation under boundary lubrication is the strongest, followed by oil-rich and dry friction. Thus, friction coefficient or vibration can be selected according to the convenience of measurement to monitor the running-in process.
Thermogravimetric Kinetics Study of Scrap Tires Pyrolysis Using Silica Embedded With NiO and/or MgO Nanocatalysts
Authors: Alsurakji Ihab H. , El-Qanni Amjad , El-Hamouz Amer M. , Warad Ismail , Odeh Yazan
Published: April 2021

In this study, a set of three new silica-based embedded with NiO and/or MgO nanocatalysts (SBNs) have been prepared and tested for the pyrolysis of scrap tires (STs). The intent is to identify and optimize the best nanocatalyst that decreases the operating temperature and speeds up the pyrolysis reaction rate. The influence of the three prepared SBNs nanocatalysts on STs was scrutinized using thermogravimetric analysis (TGA) and Fourier transform infrared spectroscopy (FT-IR). The kinetic triplets were estimated utilizing the isoconversional method of the Ozawa–Flynn–Wall (OFW) corrected model. Experimental TGA and FT-IR results showed a thermal decomposition of all volatile organic additives alongside the polyvinyl compounds at a lower temperature in the presence of these SBNs. However, a competitive decomposition behavior appeared for each SBN nanocatalysts. The kinetic triplets’ findings showed different effective activation energy trends at two different conversion regions (low and high conversions), suggesting different reaction mechanisms confirmed by the reaction kinetic models. Interestingly, NiO-MgO-SBNs showed the highest reaction rate for this thermo-pyrolysis of STs, which could be because of synergetic interaction between NiO and MgO nanoparticles. Moreover, the results of the change in Gibbs free energy of activation (ΔG‡) indicated the promising catalytic activity for those SBNs by promoting the spontaneity of pyrolysis reaction. These proof-of-concept findings could promote the futuristic use of NiO-MgO-SBNs at the industrial level toward sustainable ST pyrolysis.
Longitudinal wave attenuation in polycrystals with elongated grains: 3D numerical and analytical modeling
Authors: Huang M. , Sha G. , Huthwaite P. , Rokhlin S. I. , Lowe M. J. S.
Published: April 2021

This work develops a second-order approximation (SOA) model and a three-dimensional (3D) finite element (FE) model to calculate scattering-induced attenuation for elastic wave propagation in polycrystals with elongated grains of arbitrary crystal symmetry. The SOA model accounts for some degree of multiple scattering, whereas the 3D FE model includes all scattering possibilities. The SOA model incorporates the accurate geometric two-point correlation function obtained from the FE material systems to enable comparative studies between the two models. Also, the analytical Rayleigh and stochastic asymptotes are presented to provide explicit insights into propagation behaviors. Quantitative agreement is found between the FE and analytical models for all evaluated cases. In particular, the FE simulations support the SOA model prediction that grain shape does not exert influence on attenuation in the Rayleigh regime and its effect emerges as frequency increases to the stochastic regime showing anisotropy in attenuation. This attenuation anisotropy intensifies with the increase in frequency, but it exhibits a complicated behavior as frequency transits into the geometric regime. Wavefield fluctuations captured from the FE simulations are provided to help observe these complex scattering behaviors. The proportionality of attenuation to elastic scattering factors is also quantitatively evaluated.
Coproduction of Tet(X7) Conferring High-Level Tigecycline Resistance, Fosfomycin FosA4, and Colistin Mcr-1.1 in Escherichia coli Strains from Chickens in Egypt
Authors: Soliman Ahmed M. , Ramadan Hazem , Zarad Hoda , Sugawara Yo , Yu Liansheng , Sugai Motoyuki , Shimamoto Toshi , Hiott Lari M. , Frye Jonathan G. , Jackson Charlene R. , Shimamoto Tadashi
Published: April 2021

The plasmid-mediated
tet
(X7) conferring high-level tigecycline resistance was identified in five
mcr-1.1
-positive
Escherichia coli
strains (ST10 [
n
 = 3] and ST155 [
n
 = 2]) isolated from chickens in Egypt. Two fosfomycin-resistant
fosA4
-carrying IncFII plasmids (⁓79 kb in size) were detected.
Effect of Leu
277
on Disproportionation and Hydrolysis Activity in Bacillus stearothermophilus NO2 Cyclodextrin Glucosyltransferase
Authors: Kong Demin , Wang Lei , Su Lingqia , Wu Jing
Published: April 2021

In this study, mutations that enhance the disproportionation to hydrolysis ratio of a CGTase have been discovered. For example, the disproportionation-to-hydrolysis ratio of the L277M mutant of
Bacillus stearothermophilus
NO2 CGTase was 2.4-fold greater than that of the wild type.
Medical emergency: rash, headache and spinal cord injury
Authors: Wells Tom
Published: April 2021

A 49-year-old consultant medical oncologist, with a medical history of complete T5 spinal cord injury (March 1992) and long-term paralysis from the chest down, presented with shingles affecting the T7 dermatome. He also had a dull frontal headache, a feeling of agitation and increased blood pressure of 135/90 on a home blood pressure machine (higher than his usual blood pressure of 90/70). Having been taught about autonomic dysreflexia at the time of his initial spinal cord injury, he self-diagnosed autonomic dysreflexia caused by the noxious stimulus of shingles below his level of spinal cord injury. He self-administered a nifedipine 5 mg sublingual capsule to decrease his blood pressure before urgently seeing his general practitioner. Treatment of the shingles with acyclovir and analgesia successfully managed the problem and avoided hospital admission. This case highlights key aspects in treating autonomic dysreflexia and the value of doctor–patient partnership in doing so.
Fibromuscular dysplasia with unilateral renal agenesis
Authors: Woods Demi Jordan , Woods Zakary John , Alter Kevin , Choudhury Adnan Z
Published: April 2021

Fibromuscular dysplasia (FMD) is predominantly diagnosed in women and is a congenital malformation damaging the arterial cell walls of numerous arteries, most prominently impacting the renal arteries. Although previously believed to be a disease of young women, older patients have been shown to make up a large percentage of this patient population as well. FMD is underdiagnosed, and the misdiagnosis of this disease has life-threatening consequences. Here, we present the case of a 24-year-old woman with hypertension who did not receive adequate workup until her symptoms were unrelenting. Her hypertension was presumed to be a result of her generalised anxiety disorder. However, once she began to experience vision changes and significant headaches, further workup ensued. This case exemplifies the importance of performing a thorough evaluation of all patients that present with hypertension of unknown origin, especially young women. To decrease the risk of permanent consequences such as strokes, renal failure and even death, the correct diagnosis of FMD is vital.
Herpes simplex virus esophagitis—clinical challenges in the elderly
Authors: Custódio Sara Fernandes , Félix Catarina , Cruz Fátima , Veiga Manuela Zita
Published: April 2021

A 77-year-old woman presented with a 2-week history of malaise, prostration, anorexia, abdominal pain, vomiting and diarrhoea. She had been taking systemic corticosteroids for the past year. During hospitalisation, renal insufficiency, ionic changes and liver function abnormalities were detected and corrected. However, the patient developed total dysphagia. UGE revealed multiple shallow ulcers below the cricopharyngeal level and in the distal oesophagus, with normal-appearing intervening mucosa. Histological examination allowed the diagnosis of herpes simplex virus esophagitis. Treatment with intravenous acyclovir was instituted for 14 days. In the elderly, herpetic esophagitis may present with non-specific complains, such as prostration or anorexia. In the reported case, dysphagia was only detected as a late symptom, addressing the importance of maintaining a high degree of suspicion for the diagnosis of herpes simplex virus esophagitis.
Distribution and associations of vision-related quality of life and functional vision of children with visual impairment
Authors: Robertson Alexandra O , Horvat-Gitsels Lisanne A , Cortina-Borja Mario , Rahi Jugnoo S
Published: April 2021

Background

Patient-reported outcome measures (PROMs) are increasingly used in paediatric ophthalmology. However, little is known about the distribution of PROM scores among children and young people with visual impairment.

Aim

To investigate the distributions and predictors of scores on the VQoL_CYP (measuring vision-related quality of life) and FVQ_CYP (measuring functional vision).

Methods

Children and young people aged 8–18 years, with visual impairment/blindness (logarithm of the minimum angle of resolution (LogMAR) worse than 0.48 in the better eye, and/or eligible visual field restriction) completed the VQoL_CYP and FVQ_CYP at home or Great Ormond Street Hospital, London, UK. Associations between VQoL_CYP and FVQ_CYP scores and sociodemographic and clinical factors were analysed using multiple linear regression models.

Results

Among 93 participants, VQoL_CYP scores ranged from 36.6 to 78.2 (mean=57.9, SD=8.1). FVQ_CYP scores ranged from 23.5 to 70.3 (mean=48.3, SD=10.1). Only 0.4% of the variation in VQoL_CYP scores was explained, with no associations with the variables of interest. By contrast, 21.6% of the variation in FVQ_CYP scores was explained, with a gradient of worse acuity (p<0.001) and female gender (p=0.04) associated with worse self-rated functional vision. Age, ethnicity, time of onset and stability/progression of visual impairment were not associated.

Discussion

Self-rated vision-related quality of life and functional vision are not readily predicted from sociodemographic or clinical characteristics that ophthalmologists measure/record. Routine use of PROMs in clinical practice can offer important insights. Use in research can provide valuable measures of effectiveness of interventions. The reference values provided will aid interpretation in both settings.
Validity of the Taiwan Triage and Acuity Scale in mainland China: a retrospective observational study
Authors: Chen Qing-Qing , Chiu Sherry Yueh-Hsia , Tsai Lai-Yin , Hu Rong-Fang
Published: April 2021

Objectives

The Taiwan Triage and Acuity Scale (TTAS), developed for use in EDs, has been shown to be an excellent tool for triaging patients with high predictive performance, with an area under the receiver operating curve (AUROC) of 0.75. TTAS has been widely used in hospitals in Taiwan since 2010, but its utility has not been studied outside of Taiwan. Thus, the aim of this study was to evaluate the validity of using the TTAS in the ED of a tertiary hospital in mainland China to predict patient outcomes.

Methods

A retrospective observational study was performed on patients 14 years of age or older attending the ED of a tertiary hospital in mainland China between 1 January 2016 and 31 March 2016. The validity of the TTAS in predicting hospital admission, intensive care unit (ICU) admission, death, ED length of stay (LOS) and ED resource utilisation was evaluated by determining the correlation of these outcomes with the TTAS, AUROC and test characteristics.

Results

A total of 7843 patients were included in this study. There were significant differences between the TTAS categories in disposition, ED LOS and ED resource utilisation (p<0.0001). The TTAS was significantly correlated with patient disposition at discharge, hospital admission, ICU admission and death in the ED (Kendall rank correlations were 0.254, –0.254, −0.079 and −0.071, respectively; p=0.001). The AUROCs for the prediction of hospital admissions, ICU admissions and deaths in the ED were 0.749 (95% CI 0.732 to 0.765), 0.869 (95% CI 0.797 to 0.942) and 0.998 (95% CI 0.995 to 1.000), respectively. Our results demonstrated better performance using the TTAS for predictions of ICU admission and death.

Conclusions

The TTAS had good validity in predicting patient outcomes and ED resource utilisation in a tertiary hospital in mainland China. Compared with the performance of the TTAS in Taiwan, our results suggest that the TTAS can usefully be applied outside of Taiwan.
COVID-19 pandemic, the scarcity of medical resources, community-centred medicine and discrimination against persons with disabilities
Authors: Panocchia Nicola , D'ambrosio Viola , Corti Serafino , Lo Presti Eluisa , Bertelli Marco , Scattoni Maria Luisa , Ghelma Filippo
Published: April 2021

This research aims to examine access to medical treatment during the COVID-19 pandemic for people living with disabilities. During the COVID-19 pandemic, the practical and ethical problems of allocating limited medical resources such as intensive care unit beds and ventilators became critical. Although different countries have proposed different guidelines to manage this emergency, these proposed criteria do not sufficiently consider people living with disabilities. People living with disabilities are therefore at a higher risk of exclusion from medical treatments as physicians tend to assume they have poor quality of life, whereas access to medical treatment should be based on several parameters, including clinical data and prognosis. However, the COVID-19 pandemic shifts the medical paradigm from person-centred medicine to community-centred medicine, challenging the main ethical theories. We reviewed the main guidelines and recommendations for resources allocation and examined their position toward persons with disabilities. Based on our findings, we propose criteria for not discriminating against people with disabilities in allocating resources. The shift from person-centred to community-centred medicine offers opportunities but also risks sacrificing the most vulnerable people. The principle of reasonable accommodation must always be considered to guarantee the rights of persons with disabilities.
Priority vaccination for mental illness, developmental or intellectual disability
Authors: Shevzov-Zebrun Nina , Caplan Arthur L
Published: April 2021

Coronavirus vaccines have made their debut. Now, allocation practices have stepped into the spotlight. Following Centers for Disease Control and Prevention guidelines, states and healthcare institutions initially prioritised healthcare personnel and elderly residents of congregant facilities; other groups at elevated risk for severe complications are now becoming eligible through locally administered programmes. The question remains, however: whoelseshould be prioritised for immunisation? Here, we call attention to individuals institutionalised with severe mental illnesses and/or developmental or intellectual disabilities—a group highly susceptible to the damages of COVID-19, recent research shows, and critical to consider for priority vaccination. The language describing both federal-level and state-level intentions for this population remains largely vague, despite the population’s diversity across age, diagnosis, functional status and living arrangement. Such absence of specificity, in turn, leaves room for confusion and even neglect of various subgroups. We review data stressing this group’s vulnerability, as well as select state plans for priority vaccination, highlighting the importance of clarity when describing intentions to vaccinate, or even generally care for, diverse populations composed of distinct subgroups in need.
Investigating Different Metrics for Evaluation and Selection of Mutation Operators for Java
Authors: Rani Shweta , Suri Bharti
Published: April 2021

Mutation testing is a successful and powerful technique, specifically designed for injecting the artificial faults. Although it is effective at revealing the faults, test suite assessment and its reduction, however, suffer from the expense of executing a large number of mutants. The researchers have proposed different types of cost reduction techniques in the literature. These techniques highly depend on the inspection of mutation operators. Several metrics have been evolved for the same. The selective mutation technique is most frequently used by the researchers. In this paper, the authors investigate different metrics for evaluating the traditional mutation operators for Java. Results on 13 Java programs indicate how grouping few operators can impact the effectiveness of an adequate and minimal test suite, and how this could provide several cost benefits.
MULTIPLE PERIODIC SOLUTIONS OF A WITHIN-HOST MALARIA INFECTION MODEL WITH TIME DELAY
Authors: SONG TIANQI , WANG CHUNCHENG , TIAN BOPING
Published: April 2021

In this paper, we study a within-host malaria infection model recently proposed by Schneider et al. in 2018. The stability and Hopf bifurcation analysis at the interior equilibrium are carried out, finding that the basic reproduction number plays a key role in the dynamics of the model, and incrementing the time delay will induce Hopf bifurcation at this equilibrium. The global extension of the local Hopf branch is further tracked numerically by the MatLab package DDE-BIFTOOL. Neimark-Sacker bifurcation of Poincaré map and period-doubling bifurcation of the bifurcated periodic solution are also detected, resulting in the existence of quasi-periodic and multiple periodic solutions, respectively. These results reveal that Hopf bifurcation will indeed bring about the rich dynamics of the model.
PHYSIOLOGICAL RESPONSE OF PERIPHERAL NERVE TO REPETITIVE COMPRESSION: A RABBIT EXPERIMENTAL MODEL
Authors: Yoshii Yuichi , Ochiai Naoyuki
Published: April 2021

Objective: The objective of this study is to clarify the differences in physiological responses following the different modality of repetitive compressions versus continuous compression (CC) of the peripheral nerve. Methods: Thirty-two rabbits were used. Under anesthesia, four conditions of compression; CC, low-frequency release compression (LFR, one second release time every 30 s), high-frequency release compression (HFR, one second release time every 10 s), and high-frequency compression (HFC, one second compression time every 10 s) were each applied with 80[Formula: see text]mmHg of pressure for 90[Formula: see text]min to the sciatic nerve. Compound nerve action potential (CNAP) and nerve blood flow were evaluated from the beginning of compression to 90[Formula: see text]min after compression release. Endoneurial microvascular permeability was evaluated histologically. Results: During compression, the nerve blood flow and the amplitude of CNAP decreased for all four groups. There were significant delays in the recovery of the amplitude and nerve blood flow in the LFR and HFR groups compared to CC group ([Formula: see text]). Endoneurial edema was observed in the repetitive compression groups. Conclusions: Even if the overall compression time was short, the accumulation of repetitive compression-release cycles causes to delay the recovery of nerve physiological function with endoneurial edema.
EFFICIENT RISK MEASURES CALCULATIONS FOR GENERALIZED CREDITRISK+ MODELS
Authors: HUANG ZHENZHEN , KWOK YUE KUEN
Published: April 2021

Numerical calculations of risk measures and risk contributions in credit risk models amount to the evaluation of various forms of quantiles, tail probabilities and tail expectations of the portfolio loss distribution. Though the moment generating function of the loss distribution in the [Formula: see text] model is available in analytic closed form, efficient, accurate and reliable computation of risk measures (Value-at-Risk and Expected Shortfall) and risk contributions for the [Formula: see text] model poses technical challenges. We propose various numerical algorithms for risk measures and risk contributions calculations of the enhanced [Formula: see text] model under the common background vector framework using the Johnson curve fitting method, saddlepoint approximation method, importance sampling in Monte Carlo simulation and check function formulation. Our numerical studies on stylized credit portfolios and benchmark industrial credit portfolios reveal that the Johnson curve fitting approach works very well for credit portfolios with a large number of obligors, demonstrating high level of numerical reliability and computational efficiency. Once we implement the systematic procedure of finding the saddlepoint within an approximate domain, the saddlepoint approximation schemes provide efficient calculation and accurate numerical results. The importance sampling in Monte Carlo simulation methods are easy to implement, but they compete less favorably in accuracy and efficiency with other numerical algorithms. The less commonly used check function formulation is limited to risk measures calculations. It competes favorably in accuracy and reliability, but an extra optimization algorithm is required.
Vertical Dynamic Response of Rigid Circular Foundation in Multilayered Transversely Isotropic Poroelastic Half-Space
Authors: Keawsawasvong Suraparb , Senjuntichai Teerapong
Published: April 2021

The influence of anisotropic properties and layering of saturated soils on dynamic response of a circular foundation under time-harmonic vertical loading is studied in this paper. The foundation is modeled as a rigid disk, with either permeable or impermeable and smooth contact surface, whereas a multilayered transversely isotropic poroelastic half-space is defined for the supporting soil. To investigate the dynamic interaction problem, a displacement and flow boundary condition at the contact surface is constituted by employing a discretization technique and the displacement influence functions, which are obtained from the exact stiffness matrix scheme, with the stiffness matrices being presented explicitly for the first time. A set of numerical results are presented to portray the effects of anisotropic and poroelastic properties, hydraulic boundary conditions, soil heterogeneity, and frequency of excitation on vertical dynamic response of rigid circular foundations. In addition, vertical vibrations of a ring foundation and a massive circular foundation are also investigated.
An Analysis of the Effect of a Change in the Support Point Location on the Vibration of Thin-Walled Beams
Authors: Szybiński Józef , Ruta Piotr
Published: April 2021

This paper deals with an analysis of the free vibration of nonprismatic thin-walled beams, with a special focus on the effect of a change in the support point location on the eigenfrequencies of the systems. A change in the support point location is understood here as occurring within the same fixed cross-section of the beam where the latter is supported. The original elements of this study are a thin-walled beam model and a method of solving differential equations, not previously used by other authors. The equations describing the model used in this paper were derived using the momentless theory of shells and the Vlasov theory assumptions. The displacement equations were derived relative to an arbitrary rectilinear reference axis. In most works known to the authors the equations describing the vibration of the nonprismatic thin-walled beam do not take into account the effects due to the curvature of the axis formed by the shear centers. The recursive algorithm was used to solve the obtained differential equations with variable coefficients. The algorithm enables one to solve the analyzed displacement equations in the form of series relative to the orthogonal Gegenbauer polynomials. For special values of the parameter defining the order of the polynomials the Gegenbauer polynomials became Chebyshev or Lagrange polynomials. In the provided numerical example, the effect of a change in the support point location within the fixed cross-section is examined. It is also analyzed which of the approximation polynomials (Chebyshev or Lagrange polynomials) yield more precise results for a small approximation base. In order to verify the model and the effectiveness of the adopted solution method, the results obtained using this method are compared with the results yielded by FEM. The results obtained showed a significant effect of the position of the support point, within a fixed section, on the eigenfrequencies values of the thin-walled systems.
Lie centralizers at the zero products on generalized matrix algebras
Authors: Fadaee B. , Ghahramani H.
Published: April 2021

Let [Formula: see text] be a 2-torsion free unital generalized matrix algebra, and [Formula: see text] be a linear map satisfying [Formula: see text] In this paper, we study the structure of [Formula: see text] and under some mild conditions on [Formula: see text] we present the necessary and sufficient conditions for [Formula: see text] to be in terms of centralizers. We then provide the characterizations of Lie centralizers on [Formula: see text] and our results generalize some of the previous results. We also refer to some applications of our results for triangular algebras and some operator algebras.
Exploring the Success Factors of Security Token Offerings: An Empirical Approach
Authors: Beinke Jan Heinrich , Rohde Kai , Pohl Fabian , Teuteberg Frank
Published: April 2021

Initial coin offerings (ICOs) have been established as an innovative capital-raising method. Nevertheless, numerous cases of ICO fraud are having a negative impact on investors. In particular, the lack of legal certainty (e.g., creditor protection) and the lack of direct participation in a company’s success (e.g., profit distribution) have led to an increasing number of security token offerings (STOs). These offer investors a degree of legal certainty and direct participation in company profits. However, to date, little scientifically-based knowledge exists regarding the factors that influence the funding success of an STO. We address this research gap by first identifying possible success factors for funding and then systematically analyzing 38 STOs that have already been carried out in order to determine the influence of those factors. Our analysis indicates that high-quality prototypes and high-quality teams are major drivers of STO funding success. Based on these results, we discuss the implications for science and practice, outline the limitations of our work, and identify further research needs.