bluuebunny/crossref_metadata_2025 huggingface dataset:
Ultrasound Findings to Predict Risk of Recurrence in Pediatric Intussusception After Air Enema Reduction
Authors: Zhang Yuan , Shao Chun‐chun , Wei Xiu‐liang , Ni Ping‐juan , Guan Hui , Zhao Chen , Li Dian‐guo , Zhang Fei‐xue
Published: August 2021

Objectives

Intussusception is one of the most common abdominal emergencies in early children. Intussusception recurs in 8–20% of children after successful nonoperative reduction. The aim of this study was to explore the ultrasound findings to predict risk of recurrence in pediatric intussusception after air enema reduction.

Methods

A total of 336 intussusception children were followed up for 1 year after received successful air enema reduction. They were divided into the recurrent group and the non‐recurrent group. The differences of clinical characteristics, ultrasonic features, and laboratory tests were analyzed by univariate analyses and the Cox proportional hazard model.

Results

Sixty‐five children with recurrent intussusception were identified. There were statistically significances in the diameter of the mass, in the presence or absence of enlarged lymph nodes out of the sleeve, and in the sleeve between recurrent and non‐recurrent groups (P < .05). Other ultrasonic features, clinical characteristics, and blood parameters had no differences (P > .05). Multivariate Cox proportional hazard model showed that the diameter of the mass and abdominal lymph nodes may be the risk factors of intussusception recurrence (HR = 1.395, 95% CI: 1.045~1.863 and HR = 2.078, 95% CI: 1.118~3.865, P < .05). The cut‐off value of mass diameter was 2.55 cm, above which recurrence is more likely.

Conclusions

Intussusception recurrence was prone with greater mass diameter (>2.55 cm) and enlarged abdominal lymph nodes. Although these ultrasound findings for recurrence do not necessarily reduce the rate of recurrence, it can predict the recurrent possibility, and help the emergency physicians to be more vigilant in these children and better counsel parents upon discharge.
Expected Costs of Primary Dental Treatments and Endoscopic Sinus Surgery for Odontogenic Sinusitis
Authors: Craig John R. , Tataryn Roderick W. , Sibley Haley C. , Mason William D. , Deuel Joshua A. , Loyd Gary E. , Nerenz David R. , Goyal Parul
Published: August 2021

Objectives

Treatment of odontogenic sinusitis (ODS) due to apical periodontitis (AP) is highly successful when both dental treatment and endoscopic sinus surgery (ESS) are performed. Variation exists in the literature with regard to types and timing of dental treatments and ESS when managing ODS. This study modeled expected costs of different primary dental and sinus surgical treatment pathways for ODS due to AP.

Study Design

Decision‐tree economic model.

Methods

Decision‐tree models were created based on cost and treatment success probabilities. Using Medicare and consumer online databases, cost data were obtained for the following dental and sinus surgical treatments across the United States: root canal therapy (RCTx), revision RCTx, apicoectomy, extraction, dental implant, bone graft, and ESS (maxillary, ± anterior ethmoid, ± frontal). A literature review was performed to determine probabilities of dental and sinus disease resolution after different dental treatments. Expected costs were determined for primary dental extraction, RCTx, and ESS pathways, and sensitivity analyses were performed.

Results

Expected costs for the three different primary treatment pathways when dental care was in‐network and all diseased sinuses opened during ESS were as follows: dental extraction ($4,753.83), RCTx ($4,677.34), and ESS ($7,319.85).

Conclusions

ODS due to AP can be successfully treated with primary dental treatments, but ESS is still frequently required. Expected costs of primary dental extraction and RCTx were roughly equal. Primary ESS had a higher expected cost, but may still be preferred in patients with prominent sinonasal symptoms. Patients' insurance coverage may also impact decision‐making.

Level of Evidence

NA Laryngoscope, 132:1346–1355, 2022
Median duration and factors that influence the duration of symptom resolution in COVID‐19 patients in Ethiopia: A follow‐up study involving symptomatic cases
Authors: Abrahim Saro Abdella , Tessema Masresha , Ejeta Eshetu , Ahmed Mahammed , Defar Atkure , Hussen Alemayehu , Demoz Getachew , Degu Eskindir , Aseratie Mulugeta , Merga Belay , Dillnessa Enatenesh , Regassa Tegene , Duguma Dereje , Whiting Susan
Published: August 2021

Background

Understanding the clinical features of COVID‐19 and duration for resolution of symptoms is crucial for isolation of patients and tailoring public health messaging, interventions and policy. Therefore, this study aims to assess the median duration of COVID‐19 signs and symptoms’ resolution and explore its predictors among symptomatic COVID‐19 patients in Ethiopia.

Methods

A hospital‐based prospective cohort study involving 124 COVID‐19 cases was conducted at Eka Kotebe General Hospital, COVID‐19 Isolation and Treatment Center. The study participants were all symptomatic COVID‐19 adult patients admitted to the hospital from 18 March to 20 August 2020. Physicians at the centre recorded the data using a log sheet. Cox proportional‐hazards regression model was conducted. Statistical significance was defined at P < 0.05.

Results

A total of 124 symptomatic COVID‐19 patients with a mean age of 42 years (±17) were involved in the study. The median duration of symptom resolution of COVID‐19 was seven days with a minimum of two and a maximum of sixty‐eight days. Sex and body mass index (BMI) were statistically significant predictors of the symptom resolution. The hazard of having delayed sign or symptom resolution in males was 55% higher than in females (P = 0.039; CI: 0.22–0.96) and the hazard of delayed sign or symptom resolution in those with BMI ≥ 25 kg/m2 was 35% higher than in those with BMI < 25 kg/m2 (P = 0.041; CI: 0.44–0.98]).

Conclusions

The median duration of COVID‐19 symptom resolution was seven days. Being male and/or having a BMI ≥ 25 kg/m2 were predictors of a delayed sign or symptom resolution time. Therefore, it is important to consider proportion of males and those with BMI ≥ 25 kg/m2 when preparing isolation and treatment centres. Males and individuals with BMI ≥ 25 kg/m2 shall also be given priority when shielding from the COVID‐19.
Normative data for ages 18‐45 for ocular motor and vestibular testing using eye tracking
Authors: Kullmann Aura , Ashmore Robin C. , Braverman Alexandr , Mazur Christian , Snapp Hillary , Williams Erin , Szczupak Mikhaylo , Murphy Sara , Marshall Kathryn , Crawford James , Balaban Carey D. , Hoffer Michael , Kiderman Alexander
Published: August 2021

Objective

Eye tracking technology has been employed in assessing ocular motor and vestibular function following vestibular and neurologic conditions, including traumatic brain injury (TBI). Assessments include tests that provide visual and motion (rotation) stimuli while recording horizontal, vertical, and torsional eye movements. While some of these tests have shown diagnostic promise in previous studies, their use in clinical practice is limited by the lack of normative data. The goal of this study was to construct normative reference ranges to be used when comparing patients' results.

Methods

Optokinetic response, subjective visual horizontal and vertical, and rotation tests were administered to male and female volunteers, ages 18‐45, who were free from neurological, vestibular disorders, or other head injuries. Tests were administered using either a rotatory chair or a portable virtual reality‐like goggle equipped with video‐oculography.

Results

Reference values for eye movements in response to different patterns of stimuli were analyzed from 290 to 449 participants. Analysis of gender (self‐reported) or age when grouped as pediatric (late adolescent; 18‐21 years of age) and adult (21‐45 years of age) revealed no effects on the test metrics. Data were pooled and presented for each test metric as the 95% reference interval (RI) with 90% confidence intervals (CI) on upper and lower limits of the RI.

Conclusions

This normative database can serve as a tool to aid in diagnosis, treatment, and/or rehabilitation protocols for vestibular and neurological conditions, including mild TBI (mTBI). This database has been cleared by the FDA for use in clinical practice (K192186).

Level of evidence

2b
Compact High Resolution Speckle Spectrometer by Using Linear Coherent Integrated Network on Silicon Nitride Platform at 776 nm
Authors: Zhang Zunyue , Li Yuan , Wang Yi , Yu Zejie , Sun Xiankai , Tsang Hon Ki
Published: August 2021

Motivated by applications in mobile optical sensing, ultracompact high‐resolution integrated spectrometers have attracted much interest. Here, a high‐resolution integrated speckle spectrometer, comprising a linear coherent network formed by mutually coupled Mach–Zehnder interferometers and nonidentical microring resonators, is proposed and demonstrated. Deep‐etched grating lines used as mirrors on the edges of the coherent network increase the effective optical path lengths. The speckle spectrometer is realized on a silicon nitride platform, operating at 776 nm central wavelength. The eight‐in−eight‐out linear coherent network provides 64 physical channels. Fine spectral lines separated by 20 pm are experimentally resolved within a device footprint of 520 µm × 220 µm. Compressive sensing is achieved for sparse spectra over a wide optical bandwidth. Up to 600 distinctive wavelength channels can be reconstructed from the 64 physical channels, giving 12 nm operating bandwidth. Both sparse spectra and continuous spectra are well reconstructed experimentally. The integrated speckle spectrometer has great potential for use in future biosensing and bioimaging applications where high spectral resolution is desired.
Treatment of abdominal striae distensae in Fitzpatrick skin types IV to V using a 1064‐nm picosecond laser with a fractionated microlens array
Authors: Kaewkes Arisa , Manuskiatti Woraphong , Cembrano Kathryn Anne , Wanitphakdeedecha Rungsima
Published: August 2021

Background

Striae distensae are atrophic dermal scars that can cause psychosocial distress among affected patients. Despite numerous available therapeutic modalities, no gold standard treatment has been established.

Objective

To evaluate the long‐term efficacy and safety of a fractional 1064‐nm picosecond laser for the treatment of striae alba in individuals with dark skin types.

Materials and Methods

Twenty volunteers with Fitzpatrick skin types IV–V who presented with striae alba were enrolled. Subjects were treated with a fractional 1064‐nm picosecond laser for four sessions at 4‐week intervals. The skin texture, average melanin index (MI), and melanin variation score were assessed using Antera 3D® before treatment, at 1 month after the second treatment, and at 1, 3, and 6 months after the last treatment. Two independent investigators evaluated clinical improvement by comparing pretreatment and posttreatment photographs. The patient satisfaction rates were likewise assessed. Adverse effects were recorded during the entire study period.

Results

Significant improvement of skin texture was seen at 1 month after the final treatment (p < 0.001) and continuously improved until the 6‐month follow‐up visit (p = 0.003). The average MI significantly increased at 1 month after the final treatment (p < 0.001), whereas the melanin variation score decreased throughout the follow‐up period. Investigator assessment at the 6‐month follow‐up revealed that 90% of subjects had moderate to marked improvement of striae appearance. Only two of 20 subjects (10%) developed transient postinflammatory hyperpigmentation (PIH) after laser treatment.

Conclusion

Fractional picosecond 1064‐nm laser is effective and well‐tolerated for the treatment of striae alba in dark‐skinned individuals with a low incidence of PIH.
Effect of the Crosslinking Degree on Self‐Healing Poly(1,2,3‐Triazolium) Adhesive
Authors: Zhang Jun , Shang Chengyuan , Yu Zhuoer , Wang Linxiao , Tang Junkun , Huang Farong
Published: August 2021

Dynamic covalent materials are a class of polymer that could be stress‐relaxation, reprocessable, and self‐healing due to dynamic crosslinks in network. Dynamic crosslinks play an important role in the typical characteristic of self‐healing polymers. It is meaningful to understand the effect of crosslinking degree on the properties of poly(1,2,3‐triazolium) (PTAM). In this article, the dynamic covalent network of PTAM adhesive has been used to study the effect of crosslinking degree. A series of PTAM adhesive with different crosslinking degrees have been obtained by changing the amount of crosslinker. Adhesion property can first rise then fall down with the increase of crosslinking degree and the best lap‐shear strength is above 20 MPa. Creep resistance and solvent resistance can be enhanced with the increase of crosslinking degree. Self‐healing studies have shown that crosslinking degree can enhance the ability of self‐healing, but too high crosslinking degree raises the temperature of self‐healing and causes side reaction which reduces the self‐healing efficiency. These results provide some insights for the influence of the crosslinking degree on the self‐healing and the structural design of dynamic covalent materials.
Main‐Side Chain Hydrogen Bonding‐Based Self‐Healable Polyurethane with Highly Stretchable, Excellent Mechanical Properties for Self‐Healing Acid–Base Resistant Coating
Authors: Xu Heng , Tu Jing , Li Pingyun , Liang Li , Ji Jie , Xiang Guifeng , Li Haozhe , Zhang Yang , Guo Xiaode
Published: August 2021

Developing an autonomous self‐healing polyurethane (PU) elastomer with excellent mechanical properties and high ductility has attracted increasing attention. Nowadays, the synthesis of elastomers with excellent mechanical properties and rapid self‐healing at room temperature faces a huge challenge. Herein, This work reports a new supramolecular PU with excellent mechanical properties and rapid self‐healing at room temperature through the introduction of T‐type chain extender into the supramolecular polymer chain. The introduction of T‐chain extender can be used to enhance the mechanical strength of PU, and the multiple hydrogen bonds on the side‐chain provide theoretical support for the rapid self‐healing ability of PU. Maximum stress of the synthesized PU can reach 3.4 ± 0.15 Mpa, and maximum elongation at break can reach 3200% ± 160%. Due to flexibility and re‐constructability of side‐chain hydrogen bonds, PU stress repair efficiency can reach 96.7%, and can be self‐healing scratches rapidly and effectively at room temperature. The mechanical properties and self‐healing properties of PU can be adjusted by the content of T‐type chain extender. The PU is applied to the metal surface coating, which has excellent acid–base resistance, bond strength up to 2.9 ± 0.1 Mpa, and the ability to eliminate local damage on the coating surface quickly at room temperature.
Visible Light‐Regulated Heterogeneous Catalytic PET‐RAFT by High Crystallinity Covalent Organic Framework
Authors: Lu Zhen , Yang Hongjie , Fu Xiaoling , Zhao Yulai , Xiao Longqiang , Zhang Zhuofan , Hou Linxi
Published: August 2021

Covalent organic frameworks (COFs) are a class of promising photocatalysts for conversing light energy into chemical energy. Based on the tunable building blocks, COFs can be well‐designed as photocatalyst for mediating reversible addition‐fragmentation chain‐transfer (RAFT) polymerization. Herein, 1,3,6,8‐tetrakis(4‐formylphenyl)pyrene (TFPPy) and 2,2″‐bipyridine‐5,5″‐diamine (Bpy) are chosen to construct imine‐based TFPPy‐Bpy‐COFs for catalyzing RAFT polymerization of methacrylates under white light irradiation. The well‐defined polymers with precise molecular weight and narrow molecular weight distribution are obtained. The switch on/off light experiments suggest excellent temporal control toward RAFT polymerization system and the chain‐extension reaction indicates high chain‐end fidelity of macro‐initiators. Mechanism study clarifies that the electron transfer between excited state of TFPPy‐Bpy‐COFs and RAFT agent can form living radicals to mediate polymerization. This methodology provides a novel platform for reversible‐deactivation radical polymerization using COFs as heterogeneous catalysts.
Dynamic Covalent Polyurethane Network Materials: Synthesis and Self‐Healability
Authors: Nellepalli Pothanagandhi , Patel Twinkal , Oh Jung Kwon
Published: August 2021

Polyurethane (PU) has not only been widely used in the daily lives, but also extensively explored as an important class of the essential polymers for various applications. In recent years, significant efforts have been made on the development of self‐healable PU materials that possess high performance, extended lifetime, great reliability, and recyclability. A promising approach is the incorporation of covalent dynamic bonds into the design of PU covalently crosslinked polymers and thermoplastic elastomers that can dissociate and reform indefinitely in response to external stimuli or autonomously. This review summarizes various strategies to synthesize self‐healable, reprocessable, and recyclable PU materials integrated with dynamic (reversible) Diels–Alder cycloadduct, disulfide, diselenide, imine, boronic ester, and hindered urea bond. Furthermore, various approaches utilizing the combination of dynamic covalent chemistries with nanofiller surface chemistries are described for the fabrication of dynamic heterogeneous PU composites.
Aminoesterenamide Achieved by Three‐Component Reaction Heading toward Tailoring Covalent Adaptable Network with Great Freedom
Authors: Ma Youwei , Liu Zhiyong , Zhou Shuai , Jiang Xuesong , Shi Zixing , Yin Jie
Published: August 2021

Covalent adaptable networks (CANs) have recently received extensive interests due to their reprocessability and repairability. Rethinking the libraries of the published CANs, most of them are fabricated by one/two‐component reactions and few cases utilize multi‐component reactions to construct CANs while multi‐component reactions are conductive to tailoring the properties of polymers due to their structural designability and flexible choice of raw materials. A novel kind of dynamic covalent bond named aminoesterenamide is presented through three‐component reaction between acetoacetyl, amine and isocyanate. Aminoesterenamide exhibits thermal reversibility through dissociating into vinylogous urethane and isocyanate. When it is used to prepare CANs, the synthesized polymer networks can be reprocessed many times via the exchange reaction between aminoesterenamides. Moreover, the forming of aminoesterenamide involving three starting components imparts CANs with great freedom to tailor their properties. Therefore, the authors believe this method that utilizes three‐component reaction to fabricate CANs would bring new stories and perspectives to the exploration of new types of CANs.
Reversible Curvature Reversal of Monolithic Liquid Crystal Elastomer Film and Its Smart Valve Application
Authors: Han Woong Chan , Sim Gun Woo , Kim Young Been , Kim Dae Seok
Published: August 2021

Beyond a traditional stimuli‐responsive soft actuator that shows a single motion by a stimulus, multidirectional actuation reversal with a single stimulus is highly required in applications such as shape morphing sensors and soft robotics. Liquid crystal elastomers (LCEs) are one of the most attractive candidates for the soft actuator due to their capability of stimuli‐responsive shape changing in 3D, which is programmable with local orientation of LC mesogens. Here, a simple but effective method to fabricate monolithic LCE actuators that are capable of reversible curvature reversal in bending and twisting deformation by a single stimulus—heat—is reported. The curvature reversal of the LCE film can be programmed by means of asymmetric crosslinking density along the thickness and the orientation of the LC mesogens. The curvature reversal of the monolithic LCE film exhibits highly reversible (more than 100 times) and fast actuation (≈3–5 s) by heating and cooling, allowing new concept of a practical application using LCE material: a self‐regulated smart valve that is capable of qualitatively sorting liquids by temperature. It is believed that this system is potentially applied to a self‐regulated sorting platform for various endothermic and exothermic chemical or biological reactions
A simple triple‐band coupled line filtering power divider design
Authors: Zhang Zhuowei , Zhang Gang , Li Rui , Zhang Simin , Chen Qinzi , Chen Lu , Yang Zhenyuan , Tang Wanchun
Published: August 2021

In this letter, a triple‐band filtering power divider (FPD) is proposed for passive circuit implementation with a good isolation. The proposed triple‐band FPD is composed of coupled microstrip lines by applying a comprehensive design method. Based on the design method and developed topology, the employed coupled microstrip resonators, the input/output feedlines as well as isolated resistor are properly arranged to achieve a desired triple‐band filtering and isolation response. To validate our design concept and method, a triple‐band FPD operating at 2.3–2.33, 2.39–2.42, and 2.5–2.53 GHz is implemented with good return loss and isolation. Measured and simulated results are in good agreement.
Comparison of two versions of a deep learning image reconstruction algorithm on CT image quality and dose reduction: A phantom study
Authors: Greffier Joël , Dabli Djamel , Frandon Julien , Hamard Aymeric , Belaouni Asmaa , Akessoul Philippe , Fuamba Yannick , Le Roy Julien , Guiu Boris , Beregi Jean‐Paul
Published: August 2021

Purpose

To compare the impact on CT image quality and dose reduction of two versions of a Deep Learning Image Reconstruction algorithm.

Material and methods

Acquisitions on the CT ACR 464 phantom were performed at five dose levels (CTDIvol: 10/7.5/5/2.5/1 mGy) using chest or abdomen pelvis protocol parameters. Raw data were reconstructed using the filtered‐back projection (FBP), the enhanced level of AIDR 3D (AIDR 3De), and the three levels of AiCE (Mild, Standard, and Strong) for the two versions (AiCE V8 vs AiCE V10). The noise power spectrum (NPS) and task‐based transfer function (TTF) for bone (high‐contrast insert) and acrylic (low‐contrast insert) inserts were computed. To quantify the changes of noise magnitude and texture, the square root of the area under the NPS curve and the average spatial frequency (fav) of the NPS curve were measured. The detectability index (d’) was computed to model the detectability of either a large mass in the liver or lung, or a small calcification or high contrast tissue boundaries.

Results

The noise magnitude was lower with both AiCE versions than with AIDR 3De. The noise magnitude was lower with AiCE V10 than with AiCE V8 (‐4 ± 6% for Mild, ‐13 ± 3% for Standard, and ‐48 ± 0% for Strong levels). fav and TTF50% values for both inserts shifted towards higher frequencies with AiCE than with AIDR 3De. Compared to AiCE V08, fav shifted towards higher frequencies with AiCE V10 (45 ± 4%, 36 ± 3%, and 5 ± 4% for all levels, respectively). The TTF50% values shifted towards higher frequencies with AiCE V10 as compared with AiCE V8 for both inserts, except for the Strong level for the acrylic insert. Whatever the dose and AiCE levels, d’ values were higher with AiCE V10 than with AiCE V8 for the small object/calcification and for the large object/lesion.

Conclusion

As compared to AIDR 3De, lower noise magnitude and higher spatial resolution and detectability index were found with both versions of AiCE. As compared to AiCE V8, AiCE V10 reduced noise and improved spatial resolution and detectability without changing the noise texture in a simple geometric phantom, except for the Strong level. AiCE V10 seems to have a greater potential for dose reduction than AiCE V8.
Does the management of personal integrity information lead to differing participation rates and response patterns in mental health surveys with young adults? A three‐armed methodological experiment
Authors: Andersson Claes , Bendtsen Marcus , Lindfors Petra , Molander Olof , Lindner Philip , Topooco Naira , Engström Karin , Berman Anne H.
Published: August 2021

Objectives

This study evaluates whether initiation rates, completion rates, response patterns and prevalence of psychiatric conditions differ by level of personal integrity information given to prospective participants in an online mental health self‐report survey.

Methods

A three‐arm, parallel‐group, single‐blind experiment was conducted among students from two Swedish universities. Consenting participants following e‐mail invitation answered the World Health Organization (WHO) World Mental Health‐International College Student (WMH‐ICS) mental health self‐report survey, screening for eight psychiatric conditions. Random allocation meant consenting to respond (1) anonymously; (2) confidentially, or (3) confidentially, where the respondent also gave consent for collection of register data.

Results

No evidence was found for overall between‐group differences with respect to (1) pressing a hyperlink to the survey in the invitation email; and (2) abandoning the questionnaire before completion. However, participation consent and self‐reported depression were in the direction of higher levels for the anonymous group compared to the two confidential groups.

Conclusions

Consent to participate is marginally affected by different levels of personal integrity information. Current standard participant information procedures may not engage participants to read the information thoroughly, and online self‐report mental health surveys may reduce stigma and thus be less subject to social desirability bias.
Free‐breathing multitasking multi‐echo MRI for whole‐liver water‐specific T1, proton density fat fraction, and quantification
Authors: Wang Nan , Cao Tianle , Han Fei , Xie Yibin , Zhong Xiaodong , Ma Sen , Kwan Alan , Fan Zhaoyang , Han Hui , Bi Xiaoming , Noureddin Mazen , Deshpande Vibhas , Christodoulou Anthony G. , Li Debiao
Published: August 2021

Purpose

To develop a 3D multitasking multi‐echo (MT‐ME) technique for the comprehensive characterization of liver tissues with 5‐min free‐breathing acquisition; whole‐liver coverage; a spatial resolution of 1.5 × 1.5 × 6 mm3; and simultaneous quantification of T1, water‐specific T1 (T1w), proton density fat fraction (PDFF), and .

Methods

Six‐echo bipolar spoiled gradient echo readouts following inversion recovery preparation was performed to generate T1, water/fat, and contrast. MR multitasking was used to reconstruct the MT‐ME images with 3 spatial dimensions: 1 T1 recovery dimension, 1 multi‐echo dimension, and 1 respiratory dimension. A basis function–based approach was developed for T1w quantification, followed by the estimation of and T1‐corrected PDFF. The intrasession repeatability and agreement against references of MT‐ME measurements were tested on a phantom and 15 clinically healthy subjects. In addition, 4 patients with confirmed liver diseases were recruited, and the agreement between MT‐ME measurements and references was assessed.

Results

MT‐ME produced high‐quality, coregistered T1, T1w, PDFF, and maps with good intrasession repeatability and substantial agreement with references on phantom and human studies. The intra‐class coefficients of T1, T1w, PDFF, and from the repeat MT‐ME measurements on clinically healthy subjects were 0.989, 0.990, 0.999, and 0.988, respectively. The intra‐class coefficients of T1, PDFF, and between the MT‐ME and reference measurements were 0.924, 0.987, and 0.975 in healthy subjects and 0.980, 0.999, and 0.998 in patients. The T1w was independent to PDFF (R = −0.029, P = .904).

Conclusion

The proposed MT‐ME technique quantifies T1, T1w, PDFF, and simultaneously and is clinically promising for the comprehensive characterization of liver tissue properties.
An MR fingerprinting approach for quantitative inhomogeneous magnetization transfer imaging
Authors: West Daniel J. , Cruz Gastao , Teixeira Rui P. A. G. , Schneider Torben , Tournier Jacques‐Donald , Hajnal Joseph V. , Prieto Claudia , Malik Shaihan J.
Published: August 2021

Purpose

Magnetization transfer (MT) and inhomogeneous MT (ihMT) contrasts are used in MRI to provide information about macromolecular tissue content. In particular, MT is sensitive to macromolecules, and ihMT appears to be specific to myelinated tissue. This study proposes a technique to characterize MT and ihMT properties from a single acquisition, producing both semiquantitative contrast ratios and quantitative parameter maps.

Theory and Methods

Building on previous work that uses multiband RF pulses to efficiently generate ihMT contrast, we propose a cyclic steady‐state approach that cycles between multiband and single‐band pulses to boost the achieved contrast. Resultant time‐variable signals are reminiscent of an MR fingerprinting acquisition, except that the signal fluctuations are entirely mediated by MT effects. A dictionary‐based low‐rank inversion method is used to reconstruct the resulting images and to produce both semiquantitative MT ratio and ihMT ratio maps, as well as quantitative parameter estimates corresponding to an ihMT tissue model.

Results

Phantom and in vivo brain data acquired at 1.5 Tesla demonstrate the expected contrast trends, with ihMT ratio maps showing contrast more specific to white matter, as has been reported by others. Quantitative estimation of semisolid fraction and dipolar T1 was also possible and yielded measurements consistent with literature values in the brain.

Conclusion

By cycling between multiband and single‐band pulses, an entirely MT‐mediated fingerprinting method was demonstrated. This proof‐of‐concept approach can be used to generate semiquantitative maps and quantitatively estimate some macromolecular‐specific tissue parameters.
Optimization and variational principles for the shear strength reduction method
Authors: Sysala Stanislav , Hrubešová Eva , Michalec Zdeněk , Tschuchnigg Franz
Published: August 2021

In this paper, a modified shear strength reduction method (MSSR) and its optimization variant (OPT‐MSSR) are suggested. The idea of MSSR is to approximate the standard shear strength reduction to be more stable and rigorous from the numerical point of view. The MSSR method consists of a simplified associated elasto‐plastic model completed by the strength reduction depending on the dilatancy angle. Three Davis' modifications suggested by Tschuchnigg et al. (2015) are interpreted as special cases of MSSR and their factors of safety are compared. The OPT‐MSSR method is derived from MSSR on the basis of rigid plastic assumption, similarly as in limit analysis. Using the variational approach, the duality between the static and kinematic principles of OPT‐MSSR is shown. The numerical solution of OPT‐MSRR is obtained by performing a regularization method in combination with the finite element method, mesh adaptivity and a damped Newton method. In‐house codes (Matlab) are used for the implementation of this solution concept. Finally, two slope stability problems are considered, one of which follows from analysis of a real slope. The softwares packages Plaxis and Comsol Multiphysics are used for comparison of the results.
Stability of electroluminescent perovskite quantum dots light‐emitting diode
Authors: Wen Zhuoqi , Xie Fengxian , Choy Wallace. C. H.
Published: August 2021

Colloidal quantum dots (QDs) are considered to be a promising candidate for light‐emitting diodes (LEDs) applications considering their wide gamut range, simple color tuning, compatibility with large‐size and flexible substrates. Benefiting from the distinguished properties such as high photoluminescence quantum efficiency (PLQY), narrow emission linewidth, and low material cost, perovskite QDs have attracted wide attention from researchers. Despite tremendous progress has been made during the past several years, perovskite QDs‐based LEDs (QLEDs) are still plagued by the instability arising from the operation of the perovskite QLEDs, which have not been studied systematically. In this review, the origin of the instability of perovskite QLEDs is attributed to the vulnerability of emission materials and constituent layers. Simultaneously, the effective strategies to improve the durability of perovskite QDs and QLEDs are summarized, such as component engineering, ligand passivation, fabrication of robust and uniform constituent layers, as well as adopt appropriate device structures and driving modes. Ultimately, we put forward insights on the future research direction and prospects for perovskite QLEDs in practical applications.
Understanding the influence of anti‐reversion agent and metal oxide dose on natural rubber–carbon black system
Authors: Pal Koushik , Satpathi Hirak , Bhandary Tirthankar , Samui Barun Kumar , Bhattacharyya Sanjay , Naskar Kinsuk , Mukhopadhyay Rabindra
Published: August 2021

Sulfidic linkages that are formed during the vulcanization process of natural rubber (NR) are unstable at a higher temperature and can be reversed into conjugated diene. To overcome such issue and to build a compound that is hostile to inversion and with increasing service life, anti‐reversion agent (ARA), for example, N,N′‐4,4′‐diphenylmethyene bismaleimide (BMDM), is added into the formulation. This work explains the conjugation reaction mechanism of conjugated diene and BMDM by means of gas chromatography–mass spectrometry and Fourier transform infrared spectroscopy. The first phase of this study is associated with the change in ARA dosage keeping ZnO dosage the same. It is observed that 5 phr of BMDM and 2 phr ZnO combination (ARA4) shows lowest reversion at 160°C. The modulus value at 300% elongation increased 12% by the incorporation of BMDM as compared to the compound of no BMDM (ARA1). The second part is all about keeping BMDM dosage the same at 5 phr level and varying ZnO phr by 3, 4, and 5. From the overall results, it is observed that at a suitable dosage of BMDM and ZnO (5 phr BMDM and 3 phr ZnO combination [ARA5]), least reversion can be achieved and vulcanizates containing optimized BMDM and ZnO show better retention properties after aerobic aging as compared to ARA1.
On the selective killing of cold atmospheric plasma cancer treatment: Status and beyond
Authors: Yan Dayun , Horkowitz Alex , Wang Qihui , Keidar Michael
Published: August 2021

Compared with many chemotherapy and radiotherapy modalities, selective killing of cancer cells is a pivotal feature of cold atmospheric plasma (CAP). Understanding its underlying mechanism will build the foundation of CAP‐based cancer treatment. Additionally, we provided forward‐looking thinking to extend the definition of selectivity from conventional cases involving a single‐cell line to a coculture case. Finally, the newly established physically based treatment strategy provides unprecedented visions to realize selectivity beyond the previously established concepts based on reactive species and direct killing effect.
Thermal Decomposition Kinetics of Potential Solid Propellant Combustion Catalysts Fe(II), Zn(II), Hydroxylammonium, and Hydrazinium Pentazolates
Authors: Li Tian‐cheng , Lu Tong‐jie , Lei Qing , Xu Yuan‐gang , Lin Qiu‐han , Lu Ming , Lu Yan‐hua , Wang Peng‐cheng
Published: August 2021

Herein, we prepared Fe(II), Zn(II), hydroxylammonium, and hydrazinium pentazolates and investigated their thermal behavior, decomposition kinetics, and thermodynamic activation parameters. The thermolysis of metal and non‐metal salts featured three and two mass‐loss stages, respectively, with the decomposition of pentazolate anions occurring at 105–135 °C. Moreover, metal salts exhibited higher thermal safety than non‐metal salts under the same conditions. Iron and zinc pentazolates decomposed at lower temperatures than sodium pentazolate, i. e., Fe(II) and Zn(II) ions promoted the decomposition of pentazolate anions. The obtained results demonstrate that the prepared compounds hold great promise as energetic catalysts for solid propellant decomposition.
Every protagonist has a sidekick: Structural aspects of human xeroderma pigmentosum‐binding proteins in nucleotide excision repair
Authors: Feltes Bruno César
Published: August 2021

The seven xeroderma pigmentosum proteins (XPps), XPA–XPG, coordinate the nucleotide excision repair (NER) pathway, promoting the excision of DNA lesions caused by exposition to ionizing radiation, majorly from ultraviolet light. Significant efforts are made to investigate NER since mutations in any of the seven XPps may cause the xeroderma pigmentosum and trichothiodystrophy diseases. However, these proteins collaborate with other pivotal players in all known NER steps to accurately exert their purposes. Therefore, in the old and ever‐evolving field of DNA repair, it is imperative to reexamine and describe their structures to understand NER properly. This work provides an up‐to‐date review of the protein structural aspects of the closest partners that directly interact and influence XPps: RAD23B, CETN2, DDB1, RPA (RPA70, 32, and 14), p8 (GTF2H5), and ERCC1. Structurally and functionally vital domains, regions, and critical residues are reexamined, providing structural lessons and perspectives about these indispensable proteins in the NER and other DNA repair pathways. By gathering all data related to the major human xeroderma pigmentosum‐interacting proteins, this review will aid newcomers on the subject and guide structural and functional future studies.
Double Copy from Homotopy Algebras
Authors: Borsten Leron , Kim Hyungrok , Jurčo Branislav , Macrelli Tommaso , Saemann Christian , Wolf Martin
Published: August 2021

We show that the BRST Lagrangian double copy construction of supergravity as the ‘square’ of Yang–Mills theory finds a natural interpretation in terms of homotopy algebras. We significantly expand on our previous work arguing the validity of the double copy at the loop level, and we give a detailed derivation of the double‐copied Lagrangian and BRST operator. Our constructions are very general and can be applied to a vast set of examples.
20E and MAPK signal pathway involved in the effect of reproduction caused by cyantraniliprole in Bactrocera dorsalis Hendel (Diptera: Tephritidae)
Authors: Li Jianying , Liu Jin , Chi Baojie , Chen Peng , Liu Yongjie
Published: August 2021

BACKGROUND

It is a common phenomenon that insecticides affect insect reproduction and insect hormones. After cyantraniliprole treatment, the egg production and remating behavior of female Bactrocera dorsalis were affected, a phenomenon of ‘hormesis’ appeared, but the change at the molecular level was unknown. Therefore, we investigated the fertility, insect hormone titers and transcription levels and used RNAi to prove the function of genes, to explore the molecular mechanism of cyantraniliprole causing reproductive changes in female B. dorsalis.

RESULTS

LC20 treatment promoted egg production, while LC50 treatment inhibited it. Both high and low concentrations inhibited female ovaries' development and reduced the length of the ovarian tubes. Among insect hormones, only the titer of 20‐hydroxyecdysone (20E) changed significantly. According to the KEGG pathway enrichment analysis of RNA‐seq, there are significant differences in insect hormone synthesis and MAPK signal pathways between treatments. Furthermore, 20E biosynthetic genes, BdVgs and BdVgR were all down‐regulated, and multiple MAPK signaling pathway genes were up‐regulated. Based on qRT‐PCR, the expression of BdCyp307A1, BdCyp302A1, BdMEKK4 and BdMAP2K6 within 1–11 days after treatment were consistent with the change of 20E titer. The BdVg1 and BdVg2 in LC50 were still suppressed, while the LC20 returned to normal in 9–11 days. RNAi indicated that BdMEKK4 and BdMAP2K6 participated in the transcriptional regulation of BdCyp307A1 and BdCyp302A1, then affected the levels of BdVgs.

CONCLUSION

Cyantraniliprole affected 20E through MAPK signal pathway, causing many genes to be down‐regulated during the early period but up‐regulated during the late period, ultimately affecting the reproduction of B. dorsalis. © 2021 Society of Chemical Industry.
Improvement of Radiative Recombination Rate and Efficiency Droop of InGaN Light Emitting Diodes with In‐Component‐Graded InGaN Barrier
Authors: Jia Chuanyu , He Chenguang , Liang Zhiwen , Wang Qi
Published: August 2021

The influences of In‐component‐graded InGaN barrier on the performances of InGaN light emitting diodes (LEDs) are studied. The results show that LEDs with In‐component linearly graded InGaN barrier exhibit better performances of radiative recombination rate and efficiency droop than reference LED with constant‐In‐component InGaN barrier. At 150 mA, the external quantum efficiencies for LED A with constant‐In‐component InGaN barrier, LED B with the In‐component linearly increasing in the InGaN barrier, and LED C with the In‐component linearly decreasing in the InGaN barrier are 30.30%, 36.66%, and 34.03%, respectively. Among the three sets of LED samples, LED B, with the In‐component linearly increasing in the InGaN barrier, has the highest radiative recombination rate due to suppression of quantum confinement stark effect and enhancement of carrier confinement effect in the active layer. The efficiency droop for LED A, LED B, and LED C is 34.83%, 25.67%, and 16.67%, respectively. Analysis indicates that the efficiency droop is mainly determined by the hole injection efficiency and electron leakage from the active layer. LED C with the In‐component linearly decreasing in the InGaN barrier has the lowest efficiency droop due to improved hole injection efficiency and reduced electron leakage.
Phase Transformations in the AlMg Alloys Driven by High‐Pressure Torsion
Authors: Kogtenkova Olga , Straumal Boris Borisovich , Mazilkin Andrey , Czeppe Tomasz , Zięba Pawel
Published: August 2021

As‐cast aluminum–magnesium alloys with 3, 5, and 10 wt% Mg are subjected to high‐pressure torsion (HPT) at room temperature: 5 GPa, five turns with rotation speed of 1 rpm. HPT leads to the strong grain refinement for both (Al) solid solution and intermetallic β‐phase. Transmission electron microscopy (TEM), differential scanning calorimetry (DSC), and X‐ray diffraction (XRD) are used to characterize the phase transitions under heating of the HPT‐treated alloys. The decomposition of the solid solution in the ultrafine‐grained Al–10 wt% Mg alloy obtained by HPT does not follow the equilibrium diagram. The results of DSC, XRD, and TEM show that the Mg‐rich intermetallic phases appear during heating in the following sequence: GP zones → β → ε → β → γ → β. The (Al)/(Al) grain boundaries (GBs) in the fine‐grained Al–10 wt% Mg alloy after HPT and annealing up to 400 °C (i.e., in the solid solution area, far from solvus and solidus lines) contain the Mg‐rich areas. This can be the result of possible GB phase transitions with the formation of Mg‐rich GB phases. The GBs in the binary AlMg can contain the thin layers of a GB phase far away from the solvus line.
Interface States in the Acoustic Quasiperiodic System Based on Non‐Bragg Resonances
Authors: Liu Ting , Peng Shi-Jian , Zhang Jia-Yi , Fan Ya-Xian , Tao Zhi-Yong
Published: August 2021

Bragg resonances have been observed in traditional quasiperiodic waveguides for years. To enhance Bragg resonances and form Bragg gaps with high attenuation, a large number of units have been included. Here, a Fibonacci quasiperiodic acoustic waveguide based on an intense resonance mechanism is proposed to realize non‐Bragg resonances. In a waveguide with fewer units, non‐Bragg resonances can still be excited and create the related non‐Bragg gaps with high attenuation beyond the Bragg ones. Furthermore, an interface state arising in non‐Bragg gaps is experimentally observed by fabricating the mirror‐symmetry structure of Fibonacci quasi‐periodic waveguides. The field distribution of interface states exhibits a significant feature of sound energy, which is localized at a quarter wavelength from the interface of the mirror structures on both sides. Unlike the interface state in Bragg gaps (the localized sound energy distributes along the longitudinal direction), the interface state in non‐Bragg gaps displays localization along the longitudinal and radial directions, and the field distribution is like a dipole, which can be used to optimize traditional quasiperiodic waveguide structures and pave the way for various functional devices, which include multimode filters, sensors, couplers, and so on.
Magnetic Penetration Depth and Coherence Length in a Single‐Crystal YBa2Cu3O7−δ
Authors: Abou El Hassan Ahmed , Labrag Abdelaziz , Taoufik Ahmed , Bghour Mustapha , El Ouaddi Hassan , Tirbiyine Ahmed , Lmouden Brahim , Hafid Abdelhalim , El Hamidi Habiba
Published: August 2021

Herein, DC magnetization measurements of high‐quality single crystals of optimally doped YBa2Cu3O7−δ(YBCO) superconductor are reported on. The temperature and orientation dependence of the magnetic penetration depth for single‐crystal YBCO is estimated from the slope of the linear M(lnH) dependence in the London regime. The penetration depth is strongly anisotropic. Also, the electrical resistivity as a function of temperature in YBCO thin film deposited by laser ablation on the SrTiO3 substrate face is investigated around the superconducting transition region under various values of the magnetic field up to 14 T. In this work, based on the resistivity measurements, the upper critical magnetic field for both directions B∥c‐axis and B⊥c‐axis is determined with a DC weak transport current density by using 90% criteria of the normal‐state resistivity value. According to the relations and , the coherence length (0) and (0) is determined, where is the magnetic flux quantum. The anisotropy parameter is calculated and analyzed within the frame of Ginzburg–Landau theory. This result indicates that anisotropy is more evident in YBCO.
Adiabatic Switching Among Quantum Dot Eigenstates: Role of Anharmonicity and Gaussian White Noise
Authors: Roy Debi , Arif Sk. Md. , Ghosh Manas
Published: August 2021

Current study inquires the time‐dependent quantum adiabatic switching (TDQAS) among the quantum dot (QD) eigenstates under the aegis of Gaussian white noise (GWN) with special emphasis on anharmonicity that may be present in the QD potential. The initial and the final eigenstates are distinguished by different values of magnetic field strength, confinement potential, anisotropy, and anharmonicity. The QAS has been conducted using four different switching functions (SFs), e.g., square, exponential, sinusoidal, and logarithmic. The time development of switching has been monitored with the help of overlap function and quantum information entropy (QIE). The SFs appear to recover the eigenstates of QD corresponding to the final Hamiltonian. The switching paths comprise features such as enhancement, depletion, maximization, minimization, and crossover of the overlap function and entropy. These characteristics of switching paths depend on presence/absence of noise, its pathway of application (additive/multiplicative), and symmetry (odd/even) of the anharmonic potential. The dependence on the type of SF used, however, has been found to be not much significant unless the exclusive role of noise strength on switching path is observed. The study merits importance in view of immense technological applications of QD‐based systems where the noise‐anharmonicity interplay may be exploited to a great extent.