bluuebunny/crossref_metadata_2025 huggingface dataset:
Blockchain‐based patient centric health care communication system
Authors: Naresh Vankamamidi S. , Reddi Sivaranjani , Allavarpu V.V.L. Divakar
Published: February 2021

The rapid increase in health care data breaches with the existing centralized systems emphasizes a decentralized health care system while ensuring reliability, privacy, security, and trust. Further, to ensure trust in the medical community, scientist, and pharmaceutical, it is essential to improve the quality of health care data management. In this direction, we proposed a blockchain‐based decentralized privacy‐preserving EMR management (DPEM), which can ensure accountability and integrity. We propose a four‐layered framework for DPEM consisting of a data preparation layer, access control and security layer, data sharing layer, and data storage layer with the objectives: (i) To provide privacy‐preserving in DPEM, we propose a new elliptic curve‐based content extraction signature (EC‐CES) through which patients can exclude EMR's sensitive information to eradicate leakage of privacy information in the data sharing process. (ii) To provide secure data sharing, blockchain smart contracts are used to define the predefined access permissions of the patients. (iii) To provide secure storage, we use a cloud facility to store actual EMRs, and consortium blockchain is used to store respective indexes of EMRs so that the data leakages of EMRs could be optimized and simultaneously, indexes in consortium blockchain will take care the integrity of EMRs. (iv) To provide access control in data sharing, we adopted ciphertext‐policy attribute‐based encryption (CP‐ABE) access control policy to empower the owners of data to secure the cloud storage and give access to authorized users through the encrypted link to the cloud storage with access control policies blinded. Finally, the security analysis demonstrates that DPEM is an optimized way of achieving EMRs secure data sharing.
Ecohydrological characteristics of a newly identified coastal raised bog on the western Olympic Peninsula, Washington State, USA
Authors: Rocchio F. Joseph , Gage Edward , Ramm‐Granberg Tynan , Borkenhagen Andrea K. , Cooper David J.
Published: February 2021

In western North America, ombrotrophic bogs are known to occur as far south as coastal regions of British Columbia. A recent discovery of a peatland with a raised peat surface on the western Olympic Peninsula in Washington State (Crowberry Bog), USA, suggested that the distribution range of this ecosystem type extends further south along the coast. To confirm if the site was an ombrotrophic peatland, we analysed its topography, hydrologic regime, water chemistry and vegetation. LiDAR data indicated that the peatland is elevated nearly 3 m above the surrounding landscape. Water table variations in the plateau were strongly associated with seasonal and daily precipitation events, indicating ombrotrophy. The hydraulic gradient on the plateau is downward through most of the year, demonstrating that precipitation is percolating vertically into deeper peat layers. In the rand, the hydraulic gradients are horizontal over much of the year, indicating that the plateau is draining through the rand to the lagg. Calcium, magnesium and potassium occur in very low concentrations, and the only ions in higher concentration are sodium and chloride, suggesting inputs of precipitation influenced by Pacific Ocean sea spray. Distinct vegetation composition and structure are associated with the plateau, rand and lagg zones of the site. These multiple lines of evidence indicate that Crowberry Bog is an ombrotrophic peatland, the first of its type identified in the conterminous western USA and the most southerly occurrence of its type in western North America.
Comparison of levosimendan, NO, and inhaled iloprost for pulmonary hypertension reversibility assessment in heart transplant candidates
Authors: Tavares‐Silva Marta , Saraiva Francisca , Pinto Roberto , Amorim Sandra , Silva João Carlos , Leite‐Moreira Adelino F. , Maciel Maria Júlia , Lourenço André P.
Published: February 2021

Aims

Assessing reversibility of pulmonary vascular changes through vasoreactivity testing (VRT) optimizes end‐stage heart failure patient selection for heart transplant. All efforts should be made to unload the left ventricle and reduce pulmonary vascular resistance to effectively exclude irreversible pulmonary hypertension.

Methods and results

We reviewed our centre's cardiac transplant registry database (2009–2017) for VRT and compared haemodynamic responses with 40 ppm inhaled NO (n = 14), 14–17 μg inhaled iloprost (n = 7), and 24 h 0.1 μg/kg/min intravenous levosimendan (n = 14). Response to levosimendan was assessed by repeat right heart catheterization within 72 h. Baseline clinical and haemodynamic features were similar between groups. VRT was well tolerated in all patients. All drugs effectively reduced pulmonary artery pressures and transpulmonary gradient while increasing cardiac index, although levosimendan had a greater impact on cardiac index increase (P = 0.036). Levosimendan was the only drug that reduced pulmonary artery wedge pressure (P = 0.004) and central venous pressures (P < 0.001) and increased both left and right ventricular stroke work indexes (P = 0.020 and P = 0.042, respectively) and cardiac power index (P < 0.001) compared with NO and iloprost. Right ventricular end‐diastolic pressures and central venous pressure were only decreased by levosimendan. The rate of positive responses (≥10 mmHg decrease or final mean pulmonary artery pressure ≤40 mmHg with increased/unaltered cardiac index) was lower with inhaled iloprost (14%) than with either levosimendan or NO (71% and 64%, respectively; P < 0.05).

Conclusions

Levosimendan may be a safe and effective alternative for pulmonary hypertension reversibility assessment or a valuable pre‐test medical optimization tool in end‐stage heart failure patient assessment for heart transplantation offering extended haemodynamic benefits. Whether it increases the rate of positive responses or allows a better selection of candidates to heart transplantation remains to be established.
Functional outcomes with Carillon device over 1 year in patients with functional mitral regurgitation of Grades 2+ to 4+: results from the REDUCE‐FMR trial
Authors: Khan Muhammad Shahzeb , Siddiqi Tariq Jamal , Butler Javed , Friede Tim , Levy Wayne C. , Witte Klaus K. , Lipiecki Janusz , Sievert Horst , Coats Andrew J. Stewart
Published: February 2021

Aims

The objective of this study was to compare functional outcomes through 1 year in patients with core‐lab verified moderate to severe (Grades 2+ to 4+) functional mitral regurgitation (FMR) treated with the Carillon device or control in the blinded sham‐controlled REDUCE‐FMR (Carillon Mitral Contour System for Reducing Functional Mitral Regurgitation) study.

Methods and results

The main outcomes of this analysis were the change in 6 min walk test (6MWT) distance, incidence of heart failure hospitalization or death, change in New York Heart Association (NYHA) class, and change in Kansas City Cardiomyopathy Questionnaire (KCCQ) score through 1 year of follow‐up. The minimum clinically important difference (MCID) was defined as a ≥30 m increase in 6MWT distance, an NYHA decrease in ≥1 class, and a ≥3 point increase in KCCQ score. The proportion of patients achieving the MCID in each treatment group was compared using Fisher's exact test, and the number needed to treat (NNT) with the Carillon device was calculated. Among 83 patients (62 Carillon and 21 sham), no statistically significant group differences were observed in the baseline characteristics. All outcomes at 1 year numerically favoured the Carillon group, including MCID for the 6MWT distance (59% vs. 23%, P = 0.029; NNT = 2.8), NYHA class (48% vs. 33%, P = 0.38; NNT = 6.9), KCCQ score (69% vs. 47%, P = 0.14; NNT = 4.5), and freedom from heart failure hospitalization or death (60% vs. 48%, P = 0.45; NNT = 8.3).

Conclusions

REDUCE‐FMR was the first blinded sham‐controlled trial to report outcomes with percutaneous therapy for the treatment of FMR. Trends towards improvement in mean 6MWT distance, KCCQ score, and NYHA class were observed with the Carillon device. A substantially higher number of patients achieved MCID for all patient‐centred outcomes with the Carillon device compared with the sham procedure.
Long‐term outcomes of children with severe chronic pain: Comparison of former patients with a community sample
Authors: Wager Julia , Ruhe Ann‐Kristin , Stahlschmidt Lorin , Leitsch Kathrin , Claus Benedikt B. , Häuser Winfried , Brähler Elmar , Dinkel Andreas , Kocalevent Rüya , Zernikow Boris
Published: February 2021

Background

Findings on the short‐ and long‐term effectiveness of intensive interdisciplinary pain treatment (IIPT) for children with severe chronic functional pain are promising. However, a definitive appraisal of long‐term effectiveness cannot be made due to a lack of comparison groups. The aim of the present study was to compare the health status of former patients with the health status of an age‐ and sex‐matched comparison group from the community.

Methods

Data from two samples, a clinical sample of former patients (n = 162; aged 14 to 26) and an age‐ and sex‐matched community sample (n = 162), were analysed. Former patients provided data 7 years after IIPT. Pain characteristics, physical and mental health status, autonomy, coping and health care utilisation were compared between the two samples.

Results

Seven years after treatment, the majority (58%) of the clinical sample were completely pain‐free. Compared to the community sample, the clinical sample demonstrated worse physical and mental health and continued to seek more frequent health care, irrespective of whether or not they experienced ongoing chronic pain. However, the clinical sample reported better coping strategies and a comparable level of autonomy.

Conclusion

Patients experiencing severe chronic pain in childhood who engage in IIPT are likely to have recovered from their pain in early adulthood. Long‐term treatment effects may manifest in better coping strategies. However, reduced mental and physical health status may indicate a negative long‐term effect of early chronic pain experiences or a general vulnerability in people developing a chronic pain condition in childhood.

Significance

The majority of severely impaired paediatric chronic pain patients no longer suffer from chronic pain seven years after intensive interdisciplinary pain treatment. However, former patients have worse physical and mental health status than a community sample, and continue to seek out more frequent health care utilisation, irrespective of whether or not they continue to experience chronic pain. Therefore, potential negative long‐term effects of childhood chronic pain experiences need specific attention early on.
Tackling the Challenge of Extracting Microplastics from Soils: A Protocol to Purify Soil Samples for Spectroscopic Analysis
Authors: Möller Julia N. , Heisel Ingrid , Satzger Anna , Vizsolyi Eva C. , Oster S.D. Jakob , Agarwal Seema , Laforsch Christian , Löder Martin G.J.
Published: February 2021

Microplastic pollution in soils is an emerging topic in the scientific community, with researchers striving to determine the occurrence and the impact of microplastics on soil health, ecology, and functionality. However, information on the microplastic contamination of soils is limited because of a lack of suitable analytical methods. Because micro-Fourier-transform infrared spectroscopy (µ-FTIR), next to Raman spectroscopy, is one of the few methods that allows the determination of the number, polymer type, shape, and size of microplastic particles, the present study addresses the challenge of purifying soil samples sufficiently to allow a subsequent µ-FTIR analysis. A combination of freeze-drying, sieving, density separation, and a sequential enzymatic-oxidative digestion protocol enables removal of the mineral mass (>99.9% dry wt) and an average reduction of 77% dry weight of the remaining organic fraction. In addition to visual integrity, attenuated total reflectance FTIR, gel permeation chromatography, and differential scanning calorimetry showed that polyamide, polyethylene, polyethylene terephthalate, and polyvinyl chloride in the size range of 100 to 400 µm were not affected by the approach. However, biodegradable polylactic acid showed visible signs of degradation and reduced molecular weight distribution after protease treatment. Nevertheless, the presented purification protocol is a reliable and robust method to purify relatively large soil samples of approximately 250 g dry weight for spectroscopic analysis in microplastic research and has been shown to recover various microplastic fibers and fragments down to a size of 10 µm from natural soil samples. Environ Toxicol Chem 2022;41:844–857. © 2021 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC.

Abstract

A novel purification sequence for natural soil samples undergoing microplastic analysis.
Local infusion of ropivacaine for pain control after osseous free flaps: Randomized controlled trial
Authors: Roof Scott , Ferrandino Rocco , Eden Caroline , Khelemsky Yury , Teng Marita , Genden Eric , DeMaria Samuel , Miles Brett A.
Published: February 2021

Background

Donor site pain after osteocutaneous free flap surgery contributes to postoperative morbidity and impairs recovery. We evaluated the efficacy of local infusion of ropivacaine for treating donor‐site pain after surgery.

Methods

We conducted a randomized, double‐blind, placebo‐controlled trial of patients undergoing osteocutaneous fibula or scapular tip free flaps for head and neck reconstruction at Mount Sinai Hospital. Patients were randomized to receive local infusion of ropivacaine or saline. We compared Visual Analog Scale pain scores for donor‐site specific pain 48 hours after surgery.

Results

There were 8 fibular free flap and 10 scapular free flap reconstructions. Average donor‐site pain scores were 29 ± 22 and 31 ± 28 mm (P = .88) for placebo and ropivacaine arms, respectively. The trial was stopped after the planned interim analysis for futility of the intervention.

Conclusions

Local infusion of ropivacaine did not affect donor‐site specific pain scores in this population.

ClinicalTrials.gov Identifier: NCT03349034.
The Adverse Effect of Choice in Donation Decisions
Authors: Ein‐Gar Danit , Levontin Liat , Kogut Tehila
Published: February 2021

Many charitable organizations offer potential donors the option to choose their donation recipients—suggesting that organizations perceive the availability of such choice as beneficial to donation raising. Building upon research on choice aversion in the context of consumer goods and on the identifiable victim effect in the context of donation giving, we propose that the need to choose one target among multiple needy targets might, in fact, hinder donations. Results of six studies show that when prospective donors are asked to choose between two similar donation targets, they are more likely to opt out of donating altogether than when asked to donate to a single target. We show that the effect of choice on opt‐out rates in donation settings is driven by the conflict between the wish to be helpful and the wish to be fair. We further show that when the conflict is resolved and the choice does not raise fairness concerns, the effect is attenuated and opt‐out rates decline.
Effects of Sequential Sensory Cues on Food Taste Perception: Cross‐Modal Interplay Between Visual and Olfactory Stimuli
Authors: Biswas Dipayan , Labrecque Lauren I. , Lehmann Donald R.
Published: February 2021

Sensory cues are often encountered sequentially (rather than simultaneously) in retailing, food packaging, and other consumption contexts. While prior studies on effects of sensory cues have examined scenarios where the sensory cues are encountered simultaneously, this research takes the novel approach of examining order effects of different sensory cues encountered sequentially. Specifically, four experiments examine the effects of sequentially encountered visual and olfactory sensory cues on food taste perception. We theorize and find empirical evidence that an olfactory cue benefits from first encountering a visual cue, but not vice versa. More specifically, encountering a visual cue before (vs. after) an olfactory cue (i.e., V‐O vs. O‐V sequence) results in more positive outcomes (higher taste perception, volume consumed, product recommendation, and choice). Moreover, ease of processing the olfactory cue mediates the effect of sensory cue sequence on taste perception. These findings highlight the sensory cross‐modal effects of sequential visual and olfactory cues on gustatory perceptions and have implications for consumer well‐being as well as for food/beverage packaging and for designing retail outlets and restaurants.
Inhibition of HSP90 causes morphological variation in the invasive ant Cardiocondyla obscurior
Authors: Schrader Lukas , Winter Miles , Errbii Mohammed , Delabie Jacques , Oettler Jan , Gadau Jürgen
Published: February 2021

Canalization underlies the expression of steady phenotypes in the face of unsteady environmental conditions or varying genetic backgrounds. The chaperone HSP90 has been identified as a key component of the molecular machinery regulating canalization and a growing body of research suggests that HSP90 could act as a general capacitator in evolution. However, empirical data about HSP90‐dependent phenotypic variation and its evolutionary impact is still scarce, particularly for non‐model species. Here we report how pharmacological suppression of HSP90 increases morphological variation up to 87% in the invasive ant Cardiocondyla obscurior. We show that workers treated with the HSP90 inhibitor 17‐DMAG are significantly more diverse compared to untreated workers in two of four measured traits: maximal eye distance and maximal propodeal spine distance. We further find morphological differentiation between natural populations of C. obscurior in the same traits that responded to our pharmacological treatment. These findings add support for the putative impact of HSP90 on canalization, the modularity of phenotypic traits, and its potential role in morphological evolution of ants.
CircVAPA exerts oncogenic property in non‐small cell lung cancer by the miR‐876‐5p/WNT5A axis
Authors: Zhao Yan , Dai Qiangsheng , Fu Xiaohong , Chen Qianqi , Tang Yueqiang , Gao Xiaoping , Zhou Qiming
Published: February 2021

Background

Non‐small cell lung cancer (NSCLC) is one of the most fatal malignant tumors. Emerging studies have clarified the crucial roles of circular RNAs (circRNAs) in the tumorigenesis of cancers. CircVAPA was demonstrated to function in some human cancers. The present study aimed to investigate the role of circVAPA in NSCLC.

Methods

A quantitative real‐time polymerase chain reaction was used to measure the expression of genes. Actinomycin D and RNase R were employed to examine the stability of circVAPA. Cell‐counting kit‐8, 5‐ethynyl‐2′‐deoxyuridine, Transwell and sphere formation assays, and well as western blot analysis, were conducted to examine the changes of NSCLC cells in response to circVAPA knockdown. A luciferase reporter assay was conducted for the molecular mechanism.

Results

Our findings demonstrated high expression of circVAPA in tissues and cell lines of NSCLC. Knockdown of circVAPA had a suppressive effect on cell proliferation, migration, invasion and stemness, and also inhibited tumor growth in vivo. Mechanistically, circVAPA acted as a competing endogenous RNA to up‐regulate WNT5A by sponging miR‐876‐5p. Moreover, circVAPA activated Wnt/β‐catenin signaling by up‐regulation of WNT5A. Rescue assays showed that silencing of miR‐876‐5p or overexpression of WNT5A reversed the circVAPA knockdown‐mediated inhibition on cellular processes in NSCLC.

Conclusions

CircVAPA promotes aggressive phenotypes of NSCLC cells by the miR‐876‐5p/WNT5A axis activating Wnt/β‐catenin signaling.
Estimating HIV incidence in the Akwa Ibom AIDS indicator survey (AKAIS), Nigeria using the limiting antigen avidity recency assay
Authors: Negedu‐Momoh Olubunmi R , Balogun Oluseyi , Dafa Ibrahim , Etuk Akan , Oladele Edward Adekola , Adedokun Oluwasanmi , James Ezekiel , Pandey Satish R , Khamofu Hadiza , Badru Titi , Robinson Janet , Mastro Timothy D , Torpey Kwasi
Published: February 2021

Introduction

HIV incidence estimates are important to characterize the status of an epidemic, identify locations and populations at high risk and to guide and evaluate HIV prevention interventions. We used the limiting antigen avidity assay (LAg) as part of a recent infection testing algorithm to estimate HIV incidence in the Akwa Ibom AIDS Indicator Survey (AKAIS), Nigeria.

Methods

In 2017, AKAIS, a cross‐sectional population‐based study was conducted at the household (HH) level in 31 local government areas (LGAs) of Akwa Ibom state. Of the 8963 participants aged ≥15 years who were administered questionnaires for demographic and behavioural data, 8306 consented to HIV rapid testing. Whole‐blood specimens were collected from 394 preliminary HIV‐seropositive individuals for CD4+ cell count determination and plasma storage. Samples were shipped to a central quality laboratory for HIV confirmatory testing and viral load determination. A total of 370 HIV‐positive specimens were tested for the recent HIV infection using the LAg assay.

Results

Of the 8306 consenting adults, the HIV prevalence was 4.8%. Of the 370 HIV‐positive samples tested for HIV recency, the median age was 35 years, 48.8% had CD4+ cell count >500/mm3 and 81.3% was not virally suppressed. Viral suppression was greater among females (21%) than for males (13%). A total of 11 specimens were classified as recent based on the LAg assay and HIV viral load ≥1000 copies/mL. The weighted, adjusted HIV‐1 incidence was 0.41/100 person‐years (95% CI 0.16 to 0.66); translating to 13,000 new cases of HIV infections annually in Akwa Ibom, a state with a population of 5.5 million. The HIV incidence rate was similar in females and males (0.41% and 0.42% respectively). The incidence rate was the highest among participants aged 15 to 49 years (0.44%, 95% CI 0.15 to 0.74) translating to 11,000 new infections annually, about 85% of all new infections in the state.

Conclusions

The finding of the high HIV incidence among the 15 to 49‐year age group calls for renewed and innovative efforts to prevent HIV infection among young adults in Akwa Ibom state.
Examining healthcare transition experiences among youth living with HIV in Atlanta, Georgia, USA: a longitudinal qualitative study
Authors: Halyard Alexis S , Doraivelu Kamini , Camacho‐González Andrés F , del Río Carlos , Hussen Sophia A
Published: February 2021

Introduction

Virtually all youth living with HIV in paediatric/adolescent care must eventually transition to adult‐oriented HIV care settings. To date, there is limited evidence examining the perspectives of youth living with HIV longitudinally through the healthcare transition process. The objective of our study was to examine attitudes and experiences of youth living with HIV regarding healthcare transition, including potential change in attitudes and experiences over time.

Methods

We conducted a longitudinal qualitative interview study within a large, comprehensive HIV care centre in Atlanta, Georgia, USA between August 2016 and October 2019.We interviewed 28 youth living with HIV as part of a longitudinal observational cohort study of youth undergoing healthcare transition. We conducted qualitative interviews both immediately prior to, and one year following the transition from paediatric to adult‐oriented care.

Results

Six distinct themes emerged from interviews conducted with youth living with HIV pre‐transition: (1) reluctance to transition; (2) paediatric spaces as welcoming, and adult spaces as unwelcoming; (3) varying levels of preparation for transition; and (4) expectation of autonomy in the adult clinic. Analysis of post‐transition interviews with the same youth demonstrated: (1) inconsistencies in the transition experience; (2) fear and anxiety about transition quelled by experience; (3) varying reactions to newfound autonomy and (4) communication as the most valuable facilitator of successful transition.

Conclusions

This study’s longitudinal perspective on the healthcare transition experience yields insights that can be incorporated into programming targeting this critically important population. Although our study was conducted in a USA‐based clinic with co‐located paediatric and adult care services, many of our findings are likely to have relevance in other settings as well. Interventions aiming to improve HIV care engagement through transition should seek to enhance patient–provider communication in both paediatric and adult clinics, improve preparation of patients in paediatric clinics and ease patients gradually into autonomous disease management.
Computational analysis of the clinical presentation of a ligamentous Lisfranc injury
Authors: Perez M. Tyler , Owen John R. , Wayne Jennifer S.
Published: February 2021

Lisfranc injuries in the midfoot disrupt key arches of the foot which, if left untreated, can progress to pain, dysfunction, and arthritis. A clinical challenge is that 30–40% of Lisfranc injuries are missed in initial evaluations. The objective of this study was to explore different conditions of limb loading that could influence the biomechanics of the Lisfranc joint in a validated computational model. A computational model was created using SolidWorks software to represent the bones and soft tissues of the lower leg and foot. The model was compared to a cadaveric study of healthy and injured Lisfranc joints. The model was then used to simulate weight‐bearing radiographs and evaluate how muscle activity and foot position impacted the diastasis of the Lisfranc joint, a key indicator used to diagnose Lisfranc injuries. The computational model was within one standard deviation of the cadaveric study in all measurements for the healthy and injured foot. When simulating weight‐bearing radiographs, the presence of muscle activity or inversion/eversion resulted in less joint separation for the model with ligamentous Lisfranc injuries. While previous research has noted that weight‐bearing radiographs provide better conditions to assess Lisfranc injuries than nonweight‐bearing, this study suggests that in weight‐bearing radiographs both altering the position of the foot, possibly due to pain, and the active contraction of the extrinsic flexor muscles can obfuscate indications of a Lisfranc injury.
In Situ Formation of 3D Conductive and Cell‐Laden Graphene Hydrogel for Electrically Regulating Cellular Behavior
Authors: Chen Xuelong , Ranjan Vivek Damodar , Liu Sijun , Liang Yen Nan , Lim Jacob Song Kiat , Chen Hui , Hu Xiao , Zhang Yilei
Published: February 2021

Electroconductive and injectable hydrogels are attracting increasing attention owing to the needs of electrically induced regulation of cell behavior, tissue engineering of electroactive tissues, and achieving minimum invasiveness during tissue repair. In this study, a novel in situ formed 3D conductive and cell‐laden hydrogel is developed, which can be broadly used in bioprinting, tissue engineering, neuroengineering etc. An instantaneous, uniform spatial distribution and encapsulation of cells can be achieved as a result of hydrogen bonding induced hydrogel formation. Particularly, the cell‐laden hydrogel can be easily obtained by simply mixing and shaking the polydopamine (PDA) functionalized rGO (rGO‐PDA) with polyvinyl alcohol (PVA) solution containing cells. Graphene oxide is reduced and functionalized by dopamine to restore the electrical conductivity, while simultaneously enhancing both hydrophilicity and biocompatibility of reduced graphene oxide. In vitro culture of PC12 cells within the cell‐laden hydrogel demonstrates its biocompatibility, noncytotoxicity as well as the ability to support long‐term cell growth and proliferation. Enhanced neuronal differentiation is also observed, both with and without electrical stimulation. Overall, this 3D conductive, cell‐laden hydrogel holds great promise as potential platform for tissue engineering of electroactive tissues.
Tracking 3D ultrasound anatomical landmarks via three orthogonal plane‐based scale discriminative correlation filter network
Authors: Huang Yibin , He Jishuai , Wu Xu , Zhao Xiaozhi , Wu Jian
Published: February 2021

Purpose

In abdominal interventional therapy, accurate motion tracking of the target is regarded as crucial to minimize trauma and optimize dosage delivery. Meanwhile, three‐dimensional (3D) ultrasound (US) is an attractive modality to show the real‐time motion pattern of the target. In this work, we developed an accurate and robust landmark tracking algorithm for 3D US sequences.

Methods

The proposed algorithm introduces a three orthogonal planes (TOPs) based scale discriminative correlation filter network for 3D US landmarks tracking. First, we couple the fully convolutional network (FCN) with scale discriminative correlation filter (SDCF) to generate an effective tracker. And SDCF is reformulated as a differentiable layer, which ensures the network can perform scale learning and end‐to‐end training. Next, we train the end‐to‐end network on millions of natural images. Finally, we convert 3D US image to 2D three‐channel image by TOP transformation and feed them to the proposed network for performing online tracking.

Results

Online tracking performance was evaluated on the Challenge of Liver Ultrasound Tracking (CLUST) dataset with 22 sets of 3D US sequences, obtaining mean error of 1.63 ± 1.04 mm and 95th percentile (95%ile) error of 3.37 mm, when compared with manual annotations annotated by surgeons. Ablation study indicates that the promising results benefit from SDCF and scale learning, which alleviates the influence from deformation. The findings of the clinical analysis support that the proposed algorithm can work well with different initial patch sizes, which means that our algorithm has potential to lighten the burden of surgeons.

Conclusions

We propose a flexible, accurate and robust landmark tracking algorithm for the image‐guided interventions, and our algorithm is comparable with the state‐of‐the‐art approaches. The tracking accuracy and robustness show that our algorithm has potential in 3D US‐guided abdominal interventional therapies. Furthermore, more researches are needed to improve the computing speed of the algorithm to achieve real‐time tracking.
Technical Note: Small field dose correction factors for radiochromic film in lung phantoms
Authors: Charles Paul.H. , Crowe Scott.B. , Kairn Tanya
Published: February 2021

Purpose

Radiochromic film has been established as a detector that can be used without the need for perturbation correction factors for small field dosimetry in water. However, perturbation factors in low density media such as lung have yet to be published. This study calculated the factors required to account for the perturbation of radiochromic film when used for small field dosimetry in lung equivalent material.

Method

Monte Carlo simulations were used to calculate dose to Gafchromic EBT3 film when placed inside a lung phantom. The beam simulated had a nominal energy of 6 MV and the field sizes simulated ranged from 10 × 10 mm2 to 30 × 30 mm2. The lung density simulated was varied between 0.2 and 0.3 g/cm3. Each simulation was repeated with the film replaced by lung material (the same as the surrounding medium), and the required correction factors for film dosimetry in lung () were calculated by dividing the dose in lung by the dose in film.

Results

For field sizes 30 × 30 mm2 and larger, no correction factors were required. At a 20 × 20 mm2 field size, small corrections were required, but were within the approximate accuracy of film dosimetry (~2%). For a 10 × 10 mm2 field size, significant correction factors need to be applied (0.935 for lung density of 0.20 g/cm3 to 0.963 for lung density of 0.30 g/cm3). The values lower than one mean that the film is over‐responding. At the “upstream” lung‐water interface the correction factors were close to unity; while at the downstream interface the corrections required were marginally smaller to those at the center of lung. One centimeter or more away from the interfaces, the correction factor did not vary as a function distance from the interface (in the beam direction). Away from the central axis (perpendicular to the beam direction), the correction factors increased slightly (away from unity) as a function of off‐axis distance, before abruptly changing direction at the penumbra, with the film actually under‐responding by ~10% outside the field edges.

Conclusion

Accurate dosimetry of very small fields (15 × 15 mm2 or smaller) using radiochromic film requires correction factors for the perturbation of the film on the surrounding lung material. This correction factor was as high as 6.5% for a 10 × 10 mm2 field size and a density of 0.2 g/cm3. This will increase if either the density or the field size decrease further. This correction factor does not vary as a function of depth in lung once charged particle equilibrium is established.
On the impact of absorbed dose specification, tissue heterogeneities, and applicator heterogeneities on Monte Carlo‐based dosimetry of Ir‐192, Se‐75, and Yb‐169 in conventional and intensity‐modulated brachytherapy for the treatment of cervical cancer
Authors: Morcos Marc , Viswanathan Akila N. , Enger Shirin A.
Published: February 2021

Purpose

The purpose of this study was to evaluate the impact of dose reporting schemes and tissue/applicator heterogeneities for 192Ir‐, 75Se‐, and 169Yb‐based MRI‐guided conventional and intensity‐modulated brachytherapy.

Methods and Materials

Treatment plans using a variety of dose reporting and tissue/applicator segmentation schemes were generated for a cohort (n = 10) of cervical cancer patients treated with 192Ir‐based Venezia brachytherapy. Dose calculations were performed using RapidBrachyMCTPS, a Geant4‐based research Monte Carlo treatment planning system. Ultimately, five dose calculation scenarios were evaluated: (a) dose to water in water (Dw,w); (b) Dw,w taking the applicator material into consideration (Dw,wApp); (c) dose to water in medium (Dw,m); (d and e) dose to medium in medium with mass densities assigned either nominally per structure (Dm,m (Nom)) or voxel‐by‐voxel (Dm,m).

Results

Ignoring the plastic Venezia applicator (Dw,wApp) overestimates Dm,m by up to 1% (average) with high energy source (192Ir and 75Se) and up to 2% with 169Yb. Scoring dose to water (Dw,wApp or Dw,m) generally overestimates dose and this effect increases with decreasing photon energy. Reporting dose other than Dm,m (or Dm,m Nom) for 169Yb‐based conventional and intensity‐modulated brachytherapy leads to a simultaneous overestimation (up to 4%) of CTVHR D90 and underestimation (up to 2%) of bladder D2cc due to a significant dip in the mass‐energy absorption ratios at the depths of nearby targets and OARs. Using a nominal mass‐density assignment per structure, rather than a CT‐derived voxel‐by‐voxel assignment for MRI‐guided brachytherapy, amounts to a dose error up to 1% for all radionuclides considered.

Conclusions

The effects of the considered dose reporting schemes trend correspondingly between conventional and intensity‐modulated brachytherapy. In the absence of CT‐derived mass densities, MRI‐only‐based dosimetry can adequately approximate Dm,m by assigning nominal mass densities to structures. Tissue and applicator heterogeneities do not significantly impact dosimetry for 192Ir and 75Se, but do for 169Yb; dose reporting must be explicitly defined since Dw,m and Dw,w may overstate the dosimetric benefits.
Myofiber strain in healthy humans using DENSE and cDTI
Authors: Moulin Kévin , Croisille Pierre , Viallon Magalie , Verzhbinsky Ilya A. , Perotti Luigi E. , Ennis Daniel B.
Published: February 2021

Purpose

Myofiber strain, Eff, is a mechanistically relevant metric of cardiac cell shortening and is expected to be spatially uniform in healthy populations, making it a prime candidate for the evaluation of local cardiomyocyte contractility. In this study, a new, efficient pipeline was proposed to combine microstructural cDTI and functional DENSE data in order to estimate Eff in vivo.

Methods

Thirty healthy volunteers were scanned with three long‐axis (LA) and three short‐axis (SA) DENSE slices using 2D displacement encoding and one SA slice of cDTI. The total acquisition time was 11 minutes ± 3 minutes across volunteers. The pipeline first generates 3D SA displacements from all DENSE slices which are then combined with cDTI data to generate a cine of myofiber orientations and compute Eff. The precision of the post‐processing pipeline was assessed using a computational phantom study. Transmural myofiber strain was compared to circumferential strain, Ecc, in healthy volunteers using a Wilcoxon sign rank test.

Results

In vivo, computed Eff was found uniform transmurally compared to Ecc (−0.14[−0.15, −0.12] vs −0.18 [−0.20, −0.16], P < .001, −0.14 [−0.16, −0.12] vs −0.16 [−0.17, −0.13], P < .001 and −0.14 [−0.16, −0.12] vs Ecc_C = −0.14 [−0.15, −0.11], P = .002, Eff_C vs Ecc_C in the endo, mid, and epi layers, respectively).

Conclusion

We demonstrate that it is possible to measure in vivo myofiber strain in a healthy human population in 10 minutes per subject. Myofiber strain was observed to be spatially uniform in healthy volunteers making it a potential biomarker for the evaluation of local cardiomyocyte contractility in assessing cardiovascular dysfunction.
A plug‐and‐play, lightweight, single‐axis gradient insert design for increasing spatiotemporal resolution in echo planar imaging‐based brain imaging
Authors: Versteeg Edwin , van der Velden Tijl A. , van Leeuwen Carel C. , Borgo Martino , Huijing Erik R. , Hendriks Arjan D. , Hendrikse Jeroen , Klomp Dennis W. J. , Siero Jeroen C. W.
Published: February 2021

The goal of this study was to introduce and evaluate the performance of a lightweight, high‐performance, single‐axis (z‐axis) gradient insert design primarily intended for high‐resolution functional magnetic resonance imaging, and aimed at providing both ease of use and a boost in spatiotemporal resolution. The optimal winding positions of the coil were obtained using a genetic algorithm with a cost function that balanced gradient performance (minimum 0.30 mT/m/A) and field linearity (≥16 cm linear region). These parameters were verified using field distribution measurements by B0‐mapping. The correction of geometrical distortions was performed using theoretical field distribution of the coil. Simulations and measurements were performed to investigate the echo planar imaging echo‐spacing reduction due to the improved gradient performance. The resulting coil featured a 16‐cm linear region, a weight of 45 kg, an installation time of 15 min, and a maximum gradient strength and slew rate of 200 mT/m and 1300 T/m/s, respectively, when paired with a commercially available gradient amplifier (940 V/630 A). The field distribution measurements matched the theoretically expected field. By utilizing the theoretical field distribution, geometrical distortions were corrected to within 6% of the whole‐body gradient reference image in the target region. Compared with a whole‐body gradient set, a maximum reduction in echo‐spacing of a factor of 2.3 was found, translating to a 344 μs echo‐spacing, for a field of view of 192 mm, a receiver bandwidth of 920 kHz and a gradient amplitude of 112 mT/m. We present a lightweight, single‐axis gradient insert design that can provide high gradient performance and an increase in spatiotemporal resolution with correctable geometrical distortions while also offering a short installation time of less than 15 min and minimal system modifications.
Using a Microsimulation of Energy Balance to Explore the Influence of Prenatal Sugar‐Sweetened Beverage Intake on Child BMI
Authors: Kasman Matt , Heuberger Benjamin , Mack‐Crane William , Purcell Rob , Hammond Ross A. , Oken Emily , Kleinman Ken P.
Published: February 2021

Objective

Experiments with animals suggest that high sugar consumption during pregnancy may predispose offspring to obesity, but few human studies have examined this relationship. This study explored the association between the consumption of sugar‐sweetened beverages (SSBs) during pregnancy and caloric intake through childhood.

Methods

Using cohort data on child weight, height, and physical activity levels, a lab‐validated microsimulation model of energy balance was employed to infer the caloric intake of children through age 11 years. Random effects models were then employed to explore the relationships between prenatal maternal consumption and inferred caloric intake during childhood.

Results

An additional daily serving of SSBs during the second trimester of pregnancy was associated with an increase in child consumption of 13 kcal/d (95% CI: 1.2‐26.8). Age‐stratified models adjusting for maternal and child covariates suggested that this association was strongest for children aged 2.5 to 5.5 years. The consumption of SSBs during the first trimester was not found to have a consistently positive relationship to caloric intake.

Conclusions

These findings suggest that SSB consumption during the second trimester of pregnancy is associated with child energy intake and may influence anthropometry in early childhood, which is consistent with and suggestive of the presence of biological causal pathways alongside likely simultaneous contributions of social and environmental influences.
Modified resol type phenolic resin nanocomposites as surface metal coatings
Authors: Ahmed Sahar , Mohamed Moshera , Mansour Nahla , El‐Komy Doaa , Sadek Elham
Published: February 2021

Nanocomposites based on resol resin as a matrix and prepared organoclay, from Egyptian bentonite clay, as reinforcement material were synthesized. The effect of organoclay content (i.e., 0.5, 1.0, 1.5, 2.0, and 2.5 phr) on the properties of the prepared samples with respect to the prepared composites and resol resin with no clay was investigated. The prepared samples with higher organoclay content (i.e., 2.0 phr) were modified with epoxy or/and urethane resin and characterized using transmission electron microscope (TEM), X‐ray diffraction (XRD), and Fourier transform infrared measurements (FTIR). TEM showed uniform dispersion of the clay while XRD showed exfoliated structures. FTIR measurements confirmed the bond formation between epoxy or/and diisocynate with phenolic hydroxyl groups of resol resin. Mechanical properties, chemical resistance, thermal properties, and electrical volume resistivity were studied. Results showed that epoxy modified resol resin film samples with 2.0 phr organoclay exhibited higher adhesion and scratch hardness values, higher chemical resistance, thermal stability, and lower electrical conductivity compared with mixed epoxy/urethane and urethane samples as well as unmodified resol resin nanocomposite film samples. The samples could be useful as surface metal coatings.
'Smart' light‐reflective windows based on temperature responsive twisted nematic liquid crystal polymers
Authors: Kragt Augustinus J. J. , Loonen Roel C. G. M. , Broer Dirk J. , Debije Michael G. , Schenning Albert P. H. J.
Published: February 2021

'Smart' windows which reversibly increase their reflectivity upon heating are attracting considerable attention as devices for maintaining comfortable indoor environmental conditions. In this work, twisted nematic semi‐interpenetrating liquid crystal networks which lose their order upon heating are sandwiched between reflective linear polarizers. This 'smart' window reversibly decreases its transmission from about 50–10% over a wavelength range between 400 and 1100 nm upon heating, resulting in the window becoming darker and reflecting more light. This 'smart' window is potentially interesting for energy saving window applications where variation between privacy and visible light transparency states is required.
The STI1‐domain is a flexible alpha‐helical fold with a hydrophobic groove
Authors: Fry Michelle Y. , Saladi Shyam M. , Clemons William M.
Published: February 2021

STI1‐domains are present in a variety of co‐chaperone proteins and are required for the transfer of hydrophobic clients in various cellular processes. The domains were first identified in the yeast Sti1 protein where they were referred to as DP1 and DP2. Based on hidden Markov model searches, this domain had previously been found in other proteins including the mammalian co‐chaperone SGTA, the DNA damage response protein Rad23, and the chloroplast import protein Tic40. Here, we refine the domain definition and carry out structure‐based sequence alignment of STI1‐domains showing conservation of five amphipathic helices. Upon examinations of these identified domains, we identify a preceding helix 0 and unifying sequence properties, determine new molecular models, and recognize that STI1‐domains nearly always occur in pairs. The similarity at the sequence, structure, and molecular levels likely supports a unified functional role.
Amplicon sequencing detects mutations associated with pyrethroid resistance in Bemisia tabaci (Hemiptera: Aleyrodidae)
Authors: Wei Yiyun , Guan Fang , Wang Ran , Qu Cheng , Luo Chen
Published: February 2021

BACKGROUND

Bemisia tabaci (Gennadius) is a major damaging agricultural pest that exhibits high resistance to pyrethroid insecticides. L925I (TTA to ATA) and T929V (ACT to GTT) mutations in the para‐type voltage‐gated sodium channel (VGSC) are associated with resistance of B. tabaci to pyrethroids. Amplicon sequencing is a reliable and highly efficient method to detect the frequency of mutations linked with insecticide resistance.

RESULTS

Similar frequencies of L925I and T929V mutations were obtained by amplicon sequencing and Sanger sequencing (L925I: 0.3548 vs 0.3619; T929V: 0.6140 vs 0.6381) with overlap of 95% confidence interval in the SX population of B. tabaci. In five populations of B. tabaci from China, the maximum and minimum frequencies of the two mutations were found in the LN (L925I: 0.1126; T929V: 0.8834) and JS (L925I: 0.8776; T929V: 0.1166) populations by amplicon sequencing. However, there was no significant difference in frequencies between the L925I and T929V mutations. The sum frequency of L925I and T929V exceeded 0.9688 in all populations. In addition, a combining mutation, L925 + T929V (L925I and T929V located in same allele), was found in five populations by amplicon sequencing even though its highest frequency was only 0.0157.

CONCLUSION

We established an efficient approach for detecting frequency of mutation by amplicon sequencing. The frequencies of L925I and T929V in VGSC associated with pyrethroid resistance were detected in this study, which could provide foundational data for resistance management of B. tabaci.

© 2021 Society of Chemical Industry.