bluuebunny/crossref_metadata_2025 huggingface dataset:
Front Cover Image
Authors: Li Benxuan , Hou Bo , Amaratunga Gehan A. J.
Published: May 2021

Indoor photovoltaics have attracted considerable attention due to their great potential for powering low‐power electronics and photonic devices under ambient light. Bo Hou, Gehan A. J. Amaratunga and co‐authors (DOI: 10.1002/inf2.12180) provide an overview and prospect of the recent advances in various indoor photovoltaics.

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Dairy genetics and livestock breeding
Authors: Winters Marco
Published: May 2021

Background: The 21st century dairy cow is a very different animal from that of the past, even those being milked as little as 20 years ago. Since then, the production of dairy cows has substantially increased, whereas their somatic cell count has declined. Moreover, fertility has improved, foot, leg and udder conformation have seen changes for the better, and many other traits, including lameness, longevity and mastitis, are also moving in the right direction. This is as much a success story for genetics as it is for management and technology. It is impossible to apportion the exact part played by each factor – it will vary from trait to trait – but it is generally accepted that genetic gain has accounted for more than half of the improvement made in milk production over recent decades (Cassell 2001). Indeed, it is more important to continue to make these improvements than just identify the reasons for them, particularly in regards to traits affecting health, welfare and fertility. Genetic tools are playing an increasingly valuable role in this progress and should continue to do so in the future.

Aim of the article: This article highlights the genetic tools and trait selection indexes that are currently available to the dairy sector in the UK, and the genetic progress that can be achieved by using them.
Use of low bandwidth network technologies and sensors for operation and performance monitoring of rural development projects: A case study in South Africa
Authors: von Solms Sune , Meyer Johan
Published: May 2021

Poor infrastructure maintenance of basic services in developing countries undermine economic development and sustainability. The process of reactive maintenance on equipment are practiced in many rural projects, resulting in a range of challenges, including high cost, shorter life expectancy of equipment and inefficient use of project engagement time by project teams. This paper proposes the use of low data rate sensors for the monitoring of rural infrastructure to assist in the practice of preventive maintenance in rural projects. The paper argues and demonstrates the importance of on‐going operation and performance monitoring of infrastructure to implement preventive maintenance throughout the life cycle of rural infrastructure projects with the use of a case study—a remote village in rural South Africa. The implementation of preventive maintenance practices in rural projects show that project maintenance budgets can be utilized more efficiently when compared to traditional reactive maintenance. In addition to the reduction of maintenance cost, the implementation of preventive maintenance can lead to better life expectancy of equipment as well as safer operating and maintenance conditions for operators and maintenance teams. Findings reveal that the utilization of low data rate sensors for equipment operation and performance monitoring can support rural development as it assists preventive maintenance solutions, replacing reactive maintenance strategies. The paper further aims to assist project teams working in rural projects to improve support and maintenance of deployed infrastructure and equipment to improve the sustainability of these rural projects. The contribution of this paper is the demonstration of how the implementation of low bandwidth network technologies and sensors can be utilized for operation and performance monitoring in deep rural projects without incurring major costs to support the sustainability of these projects.
Utilization of GelMA with phosphate glass fibers for glial cell alignment
Authors: Keskin‐Erdogan Zalike , Patel Kapil D. , Chau David Y.S. , Day Richard M. , Kim Hae‐Won , Knowles Jonathan C.
Published: May 2021

Glial cell alignment in tissue engineered constructs is essential for achieving functional outcomes in neural recovery. While gelatin methacrylate (GelMA) hydrogel offers superior biocompatibility along with permissive structure and tailorable mechanical properties, phosphate glass fibers (PGFs) can provide physical cues for directionality of neural growth. Aligned PGFs were fabricated by a melt quenching and fiber drawing method and utilized with synthesized GelMA hydrogel. The mechanical properties of GelMA and biocompatibility of the GelMA‐PGFs composite were investigated in vitro using rat glial cells. GelMA with 86% methacrylation degree were photo‐crosslinked using 0.1%wt photo‐initiator (PI). Photocrosslinking under UV exposure for 60 s was used to produce hydrogels (GelMA‐60). PGFs were introduced into the GelMA before crosslinking. Storage modulus and loss modulus of GelMA‐60 was 24.73 ± 2.52 and 1.08 ± 0.23 kN/m2, respectively. Increased cell alignment was observed in GelMA‐PGFs compared with GelMA hydrogel alone. These findings suggest GelMA‐PGFs can provide glial cells with physical cues necessary to achieve cell alignment. This approach could further be used to achieve glial cell alignment in bioengineered constructs designed to bridge damaged nerve tissue.
Dendritic cells support a proliferative antigen‐specific T‐cell response in the presence of poly(lactic‐co‐glycolic acid)
Authors: Srinivasan Sangeetha , Elizabeth Babensee Julia
Published: May 2021

Biomaterials are known to modulate immune cell functions, which subsequently determine the host inflammatory and immune responses. Poly(lactic‐co‐glycolic acid) or PLGA, a biodegradable and biocompatible biomaterial, induces a pro‐inflammatory, mature phenotype in antigen presentation cells, namely dendritic cells (DCs) in vitro. In vivo, PLGA can boost the humoral immune response to a co‐delivered model antigen, a phenomenon known as the PLGA‐adjuvant effect. This study elucidates the link between PLGA's effect on the DC phenotype in vitro and its adjuvant effect in vivo using the CD11c‐DTR mouse model. These mice undergo conditional ablation of DCs upon treatment with diphtheria toxin. To measure immune activation, the mice were first given ovalbumin (OVA)‐reactive T cells from OT‐II/OT‐I mice. Later, the same mice received subcutaneous OVA‐loaded PLGA scaffold implants. In response to the scaffold implants, OVA‐reactive OT‐II CD4+ T cells showed decreased proliferation in the absence of CD11c+ DCs, indicating an attenuation of the PLGA‐adjuvant effect. Furthermore, PLGA may also influence the antigen cross‐presentation function of DCs, as evident with the lowered OVA‐reactive OT‐I CD8+ T‐cell response. Understanding the immunomodulatory ability of biomaterials in the context of DCs will aid in designing improved DC‐based immunotherapies against infectious diseases and cancer.
Using geographic information systems to assess community‐level vulnerability to housing insecurity in rural areas
Authors: Gleason Kristen D. , Dube Matthew , Bernier Elizabeth , Martin Jennifer
Published: May 2021

Research examining homelessness in rural areas has been sparse. The current study aims to expand conceptions of rural homelessness by mapping community‐level risk factors related to housing insecurity. Geographic information systems (GIS) techniques were used to map the distribution of select community‐level risk indicators in the State of Maine. Three methodological choices related to this process are demonstrated: (1) selection and distribution of housing insecurity risk indicators; (2) use of location quotients; and (3) use of spatial lags. After examining and mapping selected risk factors against the location of homeless service supports, four areas in Maine were identified as communities of concern for housing insecurity. Better understanding the extent and location of areas of high need that are resource poor can help service and funding agencies to plan for the more efficient and effective distribution of homeless prevention and mitigation services. Implications for research in rural areas are discussed.
Catalytic Sc(OTf)3 mediated direct asymmetric aldol reaction of (−)‐menthyl isothiocyanatoacetate with aldehydes by using (−)‐menthol as chiral auxiliary
Authors: Bhangare Dattatraya N. , Shinde Rohit G. , Pawar Pushpalata D. , Nikalje Milind D. , Lokhande Mahendra N.
Published: May 2021

This method involves the direct asymmetric aldol reaction of (−)‐menthyl isothiocyanatoacetate 5 with a variety of substituted aromatic aldehydes, which offers a convenient method for the synthesis of intermediate containing biologically relevant α‐amino β‐hydroxyl groups in oxazolidine ring. In this methodology, the products show remarkable diastereoselectivity using Sc(OTf)3 as a catalyst and easily accessible (−)‐menthol as a chiral auxiliary. This approach includes some important aspects such as mild reaction conditions, high yields, and excellent diastereoselectivity with a number of substituted aromatic aldehydes. The optimization and effect of different catalysts were studied at different reaction conditions and it is found that Sc(OTf)3 shows excellent diastereoselectivity at −45°C.
Synthesis and microbial screening of 8‐(benzyloxy)‐5‐(2‐[1,3‐diphenyl‐1H‐pyrazol‐4‐yl]thiazol‐4‐yl)quinolin‐2(1H)‐one derivatives
Authors: Choudhare Tukaram S. , Wagare Devendra S. , Kadam Vijay T. , Netankar Prashant D.
Published: May 2021

The present investigation describe the synthesis of 8‐(benzyloxy)‐5‐(2‐[1,3‐diphenyl‐1H‐pyrazol‐4‐yl]thiazol‐4‐yl)quinolin‐2(1H)‐one derivatives. Quinolin‐8‐ol was transformed by five step synthetic procedures into 8‐Benzyloxy‐5‐(2‐bromo‐acetyl)‐1H‐quinolin‐2‐one. Subsequently, 8‐Benzyloxy‐5‐(2‐bromo‐acetyl)‐1H‐quinolin‐2‐one condensed with 1,3‐Diphenyl‐1H‐pyrazole‐4‐carbothioic acid amide in the presence of acetonitrile to afford 8‐(benzyloxy)‐5‐(2‐[1,3‐diphenyl‐1H‐pyrazol‐4‐yl]thiazol‐4‐yl)quinolin‐2(1H)‐one derivatives. Synthesized compounds were screened for their antimicrobial activity against gram‐positive and gram‐negative bacteria. Most of the synthesized compounds are found to be active against tested bacterial strains and fungal strain.
Raman anisotropy in serpentine minerals, with a caveat on identification
Authors: Compagnoni Roberto , Cossio Roberto , Mellini Marcello
Published: May 2021

The serpentine minerals lizardite, polyhedral serpentine, chrysotile, antigorite and 15‐sector and 30‐sector polygonal serpentine have been studied by micro‐Raman spectroscopy, using selected samples, that had been previously characterized. The appropriate crystal orientations were determined by optical microscopy of petrographic sections. Oriented spectra, obtained using Nd‐YAG green laser radiation (532 nm), were deconvolved, extracting wavenumber and intensity values for the peaks, possibly overlapping and forming complex bands. Relevant Raman anisotropy is common and relevant in serpentine. Depending upon the orientation of the impinging laser, significant wavenumber shifts occur (up to 10 cm−1, mostly in polyhedral serpentine and lizardite). Furthermore, also, important intensity variations (up to 1 order of magnitude) occur in polyhedral serpentine, lizardite, chrysotile and antigorite as well. On the one hand, the possibly characteristic peaks have been identified and discussed. On the other hand, caution is suggested as far as the micro‐Raman characterization of polyphasic, variably oriented serpentine minerals is concerned.
The physicochemical properties and stability of flaxseed oil emulsions: effects of emulsification methods and the ratio of soybean protein isolate to soy lecithin
Authors: Liu Conghui , Wang Xin
Published: May 2021

BACKGROUND

The properties and stability of emulsion rely greatly on the emulsification method and emulsifier. In this study, different emulsification methods (high‐speed homogenization, ultrasonic treatment and their combination) were employed for the preparation of emulsions stabilized by soybean protein isolate (SPI) and soy lecithin (SLT) at three ratios. The microstructure, hydrodynamic average diameter, ζ‐potential, creaming stability and low‐field nuclear magnetic resonance relaxation behaviors of emulsions were investigated.

RESULTS

The results indicated that the influence of emulsification method was closely related to the ratio of SPI/SLT. Overall, the SPI‐SLT‐stabilized emulsion treated by ultrasound showed better stability and uniformity, while the combined treatment of high‐speed homogenization and ultrasound was helpful in improving the uniformity and stability of SPI‐stabilized Pickering emulsion. However, the SLT‐stabilized emulsions all exhibited worse uniformity in terms of particle size distribution and polydispersity index.

CONCLUSION

These results will be helpful for selecting an appropriate emulsification method and emulsifier to improve the stability of emulsions. © 2021 Society of Chemical Industry.
Gyroid‐Nanostructured All‐Solid Polymer Films Combining High H+ Conductivity with Low H2 Permeability
Authors: Kobayashi Tsubasa , Li Ya‐xin , Hirota Yuichiro , Maekawa Asako , Nishiyama Norikazu , Zeng Xiang‐bing , Ichikawa Takahiro
Published: May 2021

Gyroid‐nanostructured all‐solid polymer films with exceedingly high proton conductivity and low H2 gas permeability have been created via crosslinking polymerization of mixtures of a zwitterionic amphiphilic monomer and a polymerizable imide‐type acid that co‐organize into bicontinuous cubic liquid‐crystalline phases. The gyroid nanostructures are visualized by reconstructing a 3D electron map from the synchrotron X‐ray diffraction patterns. These films exhibit high proton conductivity of the order of 10−1 S cm−1 and extremely low H2 gas permeability of the order of 10−15 mol m m−2 s−1 Pa−1. These properties can be ascribed to the presence of the ionic liquid‐like layer along the gyroid minimal surface. Since these two characteristics are required for improving the performance of proton‐exchange membrane fuel cells, the present membrane design represents a promising strategy for the development of advanced devices, pertinent to establishing sustainable energy sources.
Poly(2‐ethyl‐2‐oxazoline) Featuring a Central Amino Moiety
Authors: Dirauf Michael , Fritz Nicole , Gottschaldt Michael , Weber Christine , Schubert Ulrich S.
Published: May 2021

The incorporation of an amino group into a bifunctional initiator for the cationic ring‐opening polymerization (CROP) is achieved in a two‐step reaction. Detailed kinetic studies using 2‐ethyl‐2‐oxazoline demonstrate the initiators’ eligibility for the CROP yielding well‐defined polymers featuring molar masses of about 2000 g mol–1. Deprotection of the phthalimide moiety subsequent to polymerization enables the introduction of a cyclooctyne group in central position of the polymer which is further exploited in a strain‐promoted alkyne‐azide click reaction (SpAAC) with a Fmoc‐protected azido lysine representing a commonly used binding motif for site specific polymer–protein/peptide conjugation. In‐depth characterization via electrospray ionization mass spectrometry (ESI) confirms the success of all post polymerization modification steps.
Stable Isotopic Niche Variability and Overlap across Four Fish Guilds in the North-Central Gulf of Mexico
Authors: Dillon Kevin S. , Fleming Christopher R. , Slife Caitlin , Leaf Robert T.
Published: May 2021

The quantification of niche diversity and niche overlap is useful for understanding the impacts of fisheries regulation and management. In this work, we evaluate isotopic niche size and overlap at the guild and species levels. Specifically, we analyzed guild- and species-specific isotopic niche space and niche space overlap using the SIBER and nicheROVER packages, and we evaluated length-specific and geographic contrasts in isotopes for fishes in the north-central Gulf of Mexico. Stable carbon and nitrogen isotope values (δ13C and δ15N) of fish species were compared among four ecotype-based fish guilds: estuarine, coastal migratory pelagic (CMP), reef, and large offshore pelagic (LOP). Significant differences in the mean stable isotope values were found among fish guilds. Estuarine guild species exhibited the highest δ13C variability, and Red Drum Sciaenops ocellatus were the most isotopically diverse. Variability of δ13C for CMP fish was comparable to that of some estuarine species, whereas reef and LOP fish were less variable. Fishes within the LOP guild had the largest δ15N range. Reef guild fishes had the smallest isotopic niche space and LOP guild species consistently had the largest, although no species in any guild occupied as large of an isotopic niche space as Red Drum. Distinct and well-separated isotopic niches were also observed between most estuarine species and CMP species; however, high niche overlap was observed for species within the reef and LOP guilds. We found a positive relationship of δ15N and fish TL for Red Drum, Blackfin Tuna Thunnus atlanticus, and Yellowfin Tuna T. albacares, and we found that δ15N values for Red Drum and Red Snapper Lutjanus campechanus showed distinct isotope differences between geographic areas. This study provides data not only on how species within and without ecotypes interact but also on the variability of their interactions, all of which can inform ecosystem-based fisheries management models.
Accelerating Medicines Partnership: Parkinson's Disease. Genetic Resource
Authors: Iwaki Hirotaka , Leonard Hampton L. , Makarious Mary B. , Bookman Matt , Landin Barry , Vismer David , Casey Bradford , Gibbs J. Raphael , Hernandez Dena G. , Blauwendraat Cornelis , Vitale Daniel , Song Yeajin , Kumar Dinesh , Dalgard Clifton L. , Sadeghi Mahdiar , Dong Xianjun , Misquitta Leonie , Scholz Sonja W. , Scherzer Clemens R. , Nalls Mike A. , Biswas Shameek , Singleton Andrew B. ,   Uniformed Services University of the Health Sciences Associates,   AMP PD Whole Genome Sequencing Working Group,   AMP PD consortium
Published: May 2021

Background

Whole‐genome sequencing data are available from several large studies across a variety of diseases and traits. However, massive storage and computation resources are required to use these data, and to achieve sufficient power for discoveries, harmonization of multiple cohorts is critical.

Objectives

The Accelerating Medicines Partnership Parkinson's Disease program has developed a research platform for Parkinson's disease (PD) that integrates the storage and analysis of whole‐genome sequencing data, RNA expression data, and clinical data, harmonized across multiple cohort studies.

Methods

The version 1 release contains whole‐genome sequencing data derived from 3941 participants from 4 cohorts. Samples underwent joint genotyping by the TOPMed Freeze 9 Variant Calling Pipeline. We performed descriptive analyses of these whole‐genome sequencing data using the Accelerating Medicines Partnership Parkinson's Disease platform.

Results

The clinical diagnosis of participants in version 1 release includes 2005 idiopathic PD patients, 963 healthy controls, 64 prodromal subjects, 62 clinically diagnosed PD subjects without evidence of dopamine deficit, and 705 participants of genetically enriched cohorts carrying PD risk‐associated GBA variants or LRRK2 variants, of whom 304 were affected. We did not observe significant enrichment of pathogenic variants in the idiopathic PD group, but the polygenic risk score was higher in PD both in nongenetically enriched cohorts and genetically enriched cohorts. The population analysis showed a correlation between genetically enriched cohorts and Ashkenazi Jewish ancestry.

Conclusions

We describe the genetic component of the Accelerating Medicines Partnership Parkinson's Disease platform, a solution to democratize data access and analysis for the PD research community. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society. This article is a U.S. Government work and is in the public domain in the USA.
Cost‐Effectiveness of Dopamine Agonists and Monoamine Oxidase B Inhibitors in Early Parkinson's Disease
Authors: McIntosh Emma , Kent Seamus , Gray Alastair , Clarke Carl E. , Williams Adrian , Jenkinson Crispin , Ives Natalie , Patel Smitaa , Rick Caroline , Wheatley Keith , Gray Richard ,   PD MED Collaborative Group
Published: May 2021

Background

The PD MED study reported small but persistent benefits in patient‐rated mobility scores and quality of life from initiating therapy with levodopa compared with levodopa‐sparing therapies in early Parkinson's disease (PD).

Objectives

The objective was to estimate the cost‐effectiveness of levodopa‐sparing therapy (dopamine agonists or monoamine oxidase type B inhibitors compared with levodopa alone.

Methods

PD MED is a pragmatic, open‐label randomized, controlled trial in which patients newly diagnosed with PD were randomly assigned between levodopa‐sparing therapy (dopamine agonists or monoamine oxidase type B inhibitors ) and levodopa alone. Mean quality‐adjusted life‐years and costs were calculated for each participant. Differences in mean quality‐adjusted life‐years and costs between levodopa and levodopa‐sparing therapies and between dopamine agonists and monoamine oxidase type B inhibitors were estimated using linear regression.

Results

Over a mean observation period of 4 years, levodopa was associated with significantly higher quality‐adjusted life‐years (difference, 0.18; 95% CI, 0.05–0.30; P < 0.01) and lower mean costs (£3390; £2671–£4109; P < 0.01) than levodopa‐sparing therapies, the difference in costs driven by the higher costs of levodopa‐sparing therapies. There were no significant differences in the costs of inpatient, social care, and institutional care between arms. There was no significant difference in quality‐adjusted life‐years between those allocated dopamine agonists and monoamine oxidase type B inhibitors (0.02; −0.17 to 0.13 in favor of dopamine agonists; P = 0.81); however costs were significantly lower for those allocated monoamine oxidase type B inhibitors (£2321; £1628–£3015; P < 0.01) because of the higher costs of dopamine agonists. There were no significant differences between arms for other costs.

Conclusions

Initial treatment with levodopa is highly cost‐effective compared with levodopa‐sparing therapies. Monoamine oxidase type B inhibitors, as initial levodopa‐sparing therapy was more cost‐effective, with similar quality‐adjusted life‐years but lower costs than dopamine agonists. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society
Long‐term hydrological assessment of remote sensing precipitation from multiple sources over the lower Yangtze River basin, China
Authors: Zhu Dehua , Ilyas Abro M. , Wang Gaoxu , Zeng Biqiu
Published: May 2021

Multi‐source remote sensing precipitation products are being used more and more frequently for rainfall analysis and hydrological applications around the world. The aim of the present study was to assess the variances and uncertainty of long‐term precipitation and corresponding hydrological simulations from 1984 to 2016 using rain gauge measurements, two satellite rainfall products retrieved from the Climate Prediction Center (CPC) and the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks – Climate Data Record (PERSIANN‐CDR) respectively, along with rainfall reanalysis data from the ERA‐Interim over the lower Yangtze River basin, China. The results indicated overestimation from ERA‐Interim and PERSIANN‐CDR on seasonal rainfall. CPC rainfall estimation had marginal bias with rain gauge measurements among all the remote sensing rainfall products on a daily scale, while the ERA‐Interim tended to overestimate when the rainfall rate was less than 50 mm. On a monthly scale, CPC rainfall estimations were very close to the rain gauge measurements, with a correlation coefficient of 0.96, whilst the ERA‐Interim rainfall products showed significant overestimation in February, March and September. Nevertheless, all remote sensing rainfall products achieved good performance in June and July, showing promising potential to be an alternative to rainfall data for long‐term water resource analysis. Furthermore, ERA‐Interim rainfall products did not perform as well as the other rainfall sources in flow simulations, as evidenced by the large root‐mean‐square error and bias. CPC rainfall products outperformed all other rainfall sources in terms of the Nash–Sutcliffe coefficient at all temporal scales. In addition, the skill scores suggested that the performance of the streamflow simulation improved significantly on a monthly scale, with a higher Nash–Sutcliffe coefficient and smaller total streamflow errors.
Matrilineal analysis of mutations in the DMD gene in a multigenerational South Indian cohort using DMD gene panel sequencing
Authors: Shastry Arun , Aravind Sankaramoorthy , Sunil Meeta , Ramesh Keerthi , Ashley Berty , T. Nithyanandan , Ramprasad Vedam L. , Gupta Ravi , Seshagiri Somasekar , Nongthomba Upendra , Phalke Sameer
Published: May 2021

Background

Duchenne muscular dystrophy (DMD) is an X‐linked recessive neuromuscular disorder characterised by progressive irreversible muscle weakness, primarily of the skeletal and the cardiac muscles. DMD is characterised by mutations in the dystrophin gene, resulting in the absence or sparse quantities of dystrophin protein. A precise and timely molecular detection of DMD mutations encourages interventions such as carrier genetic counselling and in undertaking therapeutic measures for the DMD patients.

Results

In this study, we developed a 2.1 Mb custom DMD gene panel that spans the entire DMD gene, including the exons and introns. The panel also includes the probes against 80 additional genes known to be mutated in other muscular dystrophies. This custom DMD gene panel was used to identify single nucleotide variants (SNVs) and large deletions with precise breakpoints in 77 samples that included 24 DMD patients and their matrilineage across four generations. We used this panel to evaluate the inheritance pattern of DMD mutations in maternal subjects representing 24 DMD patients.

Conclusion

Here we report our observations on the inheritance pattern of DMD gene mutations in matrilineage samples across four generations. Additionally, our data suggest that the DMD gene panel designed by us can be routinely used as a single genetic test to identify all DMD gene variants in DMD patients and the carrier mothers.
Layer potential theory for the anisotropic Stokes system with variable L∞ symmetrically elliptic tensor coefficient
Authors: Kohr Mirela , Mikhailov Sergey E. , Wendland Wolfgang L.
Published: May 2021

The aim of this paper is to develop a layer potential theory in L2‐based weighted Sobolev spaces on Lipschitz bounded and exterior domains of
, n ≥ 3, for the anisotropic Stokes system with L∞ viscosity tensor coefficient satisfying an ellipticity condition for symmetric matrices with zero matrix trace. To do this, we explore equivalent mixed variational formulations and prove the well‐posedness of some transmission problems for the anisotropic Stokes system in Lipschitz domains of
, with the given data in L2‐based weighted Sobolev spaces. These results are used to define the volume (Newtonian) and layer potentials and to obtain their properties. Then, we analyze the well‐posedness of the exterior Dirichlet and Neumann problems for the anisotropic Stokes system with L∞ symmetrically elliptic tensor coefficient by representing their solutions in terms of the obtained volume and layer potentials.
Defect measurement using the laser ultrasonic technique based on power spectral density analysis and wavelet packet energy
Authors: Yu Junya , Li Chuanliang , Qiu Xuanbing , Chen Huiqin , Zhang Weiwei
Published: May 2021

The laser ultrasonic technique (LUT) enables the analysis of complex signals and the extraction of the features of defects. The time‐domain features can be used to quantify various defects, but are negatively affected by the coupling efficiency, measurement noise, and surface roughness during LUT. This paper describes defect analysis methods based on the power spectral density and wavelet packet energy. Defects are characterized using the power of low‐frequency components after wavelet decomposition and the wavelet packet energy, and then linear relationships are established for two defect types. The R2 values of the linear fitting for the characteristic variables of the defect are greater than 0.96. The experimental results show that the proposed methods provide effective and quantitative characterization of the defect size from laser ultrasonic signals.
8+ Year Performance of the Gamma Knife Perfexion/Icon Patient Positioning System and Possibilities for Preemptive Fault Detection Using Statistical Process Control
Authors: Schlesinger David J. , Sanders Jason C. , Muller Donald A. , Nordström Håkan , Sheehan Jason P.
Published: May 2021

Background

The large fractional doses, steep dose gradients, and small targets found in intracranial radiosurgery require extremely low beam delivery uncertainty. In the case of Gamma Knife radiosurgery (GKRS), this includes minimizing patient positioning system (PPS) positioning uncertainty. Existing QA techniques are recipe based, and feature point in time pass/fail tolerances. However, modern treatment machines, including the Gamma Knife Perfexion/Icon systems, record extensive internal data in treatment logs. These data can be analyzed through statistical process control (SPC) methods which are designed to detect changes in process behavior. The purpose of this study was to characterize the long‐term (8+ year) performance of a Perfexion/Icon unit and use SPC methods to determine if performance changes could be detected at levels lower than existing QA and internal manufacturer performance tolerances.

Methods

In‐house software was developed to parse Perfexion/Icon log‐files and store relevant information on shot delivery in a relational database. A last‐in, first‐out (LIFO) queuing algorithm was created to heuristically match messages associated with a given delivered shot. Filtering criteria were developed to filter QA and uncompleted shots. The resulting matched shots were extracted. Achieved versus planned PPS position was determined for each PPS motor as well as for the vector magnitude difference in PPS position. Exponentially weighted moving average (EWMA) control charts were plotted to determine when process behavior changed over time.

Results

53833 shots were delivered over an 8+ year span in the study. The mean vector magnitude PPS difference was 32.7 µm, with 97.5% of all shots within 70.1 µm. Several changes in PPS positioning behavior were observed over time, corresponding with control system faults on several occasions requiring PPS recalibration. EWMA control charts clearly demonstrate that these faults could be identified and possibly predicted as many as 3 years before there were faults beyond control system tolerance.

Conclusion

The PPS of Gamma Knife Perfexion/Icon systems has extremely low positioning uncertainties. EWMA control chart method can be utilized to track PPS performance over time and can potentially detect changes in performance that may indicate a component requiring maintenance. This would allow planned service visits to mitigate problems and prevent unplanned downtime.
Managing tumor changes during radiotherapy using a deep learning model
Authors: Li Ruiqi , Roy Arkajyoti , Bice Noah , Kirby Neil , Fakhreddine Mohamad , Papanikolaou Niko
Published: May 2021

Purpose

We propose a treatment planning framework that accounts for weekly lung tumor shrinkage using cone beam computed tomography (CBCT) images with a deep learning‐based model.

Methods

Sixteen patients with non‐small‐cell lung cancer (NSCLC) were selected with one planning CT and six weekly CBCTs each. A deep learning‐based model was applied to predict the weekly deformation of the primary tumor based on the spatial and temporal features extracted from previous weekly CBCTs. Starting from Week 3, the tumor contour at Week N was predicted by the model based on the input from all the previous weeks (1, 2 … N − 1), and was evaluated against the manually contoured tumor using Dice coefficient (DSC), precision, average surface distance (ASD), and Hausdorff distance (HD). Information about the predicted tumor was then entered into the treatment planning system and the plan was re‐optimized every week. The objectives were to maximize the dose coverage in the target region while minimizing the toxicity to the surrounding healthy tissue. Dosimetric evaluation of the target and organs at risk (heart, lung, esophagus, and spinal cord) was performed on four cases, comparing between a conventional plan (ignoring tumor shrinkage) and the shrinkage‐based plan.

Results

he primary tumor volumes decreased on average by 38% ± 26% during six weeks of treatment. DSCs and ASD between the predicted tumor and the actual tumor for Weeks 3, 4, 5, 6 were 0.81, 0.82, 0.79, 0.78 and 1.49, 1.59, 1.92, 2.12 mm, respectively, which were significantly superior to the score of 0.70, 0.68, 0.66, 0.63 and 2.81, 3.22, 3.69, 3.63 mm between the rigidly transferred tumors ignoring shrinkage and the actual tumor. While target coverage metrics were maintained for the re‐optimized plans, lung mean dose dropped by 2.85, 0.46, 2.39, and 1.48 Gy for four sample cases when compared to the original plan. Doses in other organs such as esophagus were also reduced for some cases.

Conclusion

We developed a deep learning‐based model for tumor shrinkage prediction. This model used CBCTs and contours from previous weeks as input and produced reasonable tumor contours with a high prediction accuracy (DSC, precision, HD, and ASD). The proposed framework maintained target coverage while reducing dose in the lungs and esophagus.
Intrinsic radiomic expression patterns after 20 Gy demonstrate early metabolic response of oropharyngeal cancers
Authors: Lafata Kyle J. , Chang Yushi , Wang Chunhao , Mowery Yvonne M. , Vergalasova Irina , Niedzwiecki Donna , Yoo David S. , Liu Jian‐Guo , Brizel David M. , Yin Fang‐Fang
Published: May 2021

Purpose

This study investigated the prognostic potential of intra‐treatment PET radiomics data in patients undergoing definitive (chemo) radiation therapy for oropharyngeal cancer (OPC) on a prospective clinical trial. We hypothesized that the radiomic expression of OPC tumors after 20 Gy is associated with recurrence‐free survival (RFS).

Materials and Methods

Sixty‐four patients undergoing definitive (chemo)radiation for OPC were prospectively enrolled on an IRB‐approved study. Investigational 18F‐FDG‐PET/CT images were acquired prior to treatment and 2 weeks (20 Gy) into a seven‐week course of therapy. Fifty‐five quantitative radiomic features were extracted from the primary tumor as potential biomarkers of early metabolic response. An unsupervised data clustering algorithm was used to partition patients into clusters based only on their radiomic expression. Clustering results were naïvely compared to residual disease and/or subsequent recurrence and used to derive Kaplan‐Meier estimators of RFS. To test whether radiomic expression provides prognostic value beyond conventional clinical features associated with head and neck cancer, multivariable Cox proportional hazards modeling was used to adjust radiomic clusters for T and N stage, HPV status, and change in tumor volume.

Results

While pre‐treatment radiomics were not prognostic, intra‐treatment radiomic expression was intrinsically associated with both residual/recurrent disease (P = 0.0256, test) and RFS (HR = 7.53, 95% CI = 2.54–22.3; P = 0.0201). On univariate Cox analysis, radiomic cluster was associated with RFS (unadjusted HR = 2.70; 95% CI = 1.26–5.76; P = 0.0104) and maintained significance after adjustment for T, N staging, HPV status, and change in tumor volume after 20 Gy (adjusted HR = 2.69; 95% CI = 1.03–7.04; P = 0.0442). The particular radiomic characteristics associated with outcomes suggest that metabolic spatial heterogeneity after 20 Gy portends complete and durable therapeutic response. This finding is independent of baseline metabolic imaging characteristics and clinical features of head and neck cancer, thus providing prognostic advantages over existing approaches.

Conclusions

Our data illustrate the prognostic value of intra‐treatment metabolic image interrogation, which may potentially guide adaptive therapy strategies for OPC patients and serve as a blueprint for other disease sites. The quality of our study was strengthened by its prospective image acquisition protocol, homogenous patient cohort, relatively long patient follow‐up times, and unsupervised clustering formalism that is less prone to hyper‐parameter tuning and over‐fitting compared to supervised learning.
Deep learning‐based coronary artery motion estimation and compensation for short‐scan cardiac CT
Authors: Maier Joscha , Lebedev Sergej , Erath Julien , Eulig Elias , Sawall Stefan , Fournié Eric , Stierstorfer Karl , Lell Michael , Kachelrieß Marc
Published: May 2021

Purpose

During a typical cardiac short scan, the heart can move several millimeters. As a result, the corresponding CT reconstructions may be corrupted by motion artifacts. Especially the assessment of small structures, such as the coronary arteries, is potentially impaired by the presence of these artifacts. In order to estimate and compensate for coronary artery motion, this manuscript proposes the deep partial angle‐based motion compensation (Deep PAMoCo).

Methods

The basic principle of the Deep PAMoCo relies on the concept of partial angle reconstructions (PARs), that is, it divides the short scan data into several consecutive angular segments and reconstructs them separately. Subsequently, the PARs are deformed according to a motion vector field (MVF) such that they represent the same motion state and summed up to obtain the final motion‐compensated reconstruction. However, in contrast to prior work that is based on the same principle, the Deep PAMoCo estimates and applies the MVF via a deep neural network to increase the computational performance as well as the quality of the motion compensated reconstructions.

Results

Using simulated data, it could be demonstrated that the Deep PAMoCo is able to remove almost all motion artifacts independent of the contrast, the radius and the motion amplitude of the coronary artery. In any case, the average error of the CT values along the coronary artery is about 25 HU while errors of up to 300 HU can be observed if no correction is applied. Similar results were obtained for clinical cardiac CT scans where the Deep PAMoCo clearly outperforms state‐of‐the‐art coronary artery motion compensation approaches in terms of processing time as well as accuracy.

Conclusions

The Deep PAMoCo provides an efficient approach to increase the diagnostic value of cardiac CT scans even if they are highly corrupted by motion.
Construction and modulation of dual responsive fluorescent aggregates combined with molecular dynamics simulation
Authors: Yu Huajie , Sui Pengliang , Ge Shujin , Chang Xiujie , Li Qiuhong , Li Aixiang , Sun Xia
Published: May 2021

The fluorescent functional material prepared by combining 16‐alkyl (ferrocenyl‐methyl) ammonium bromide (Fc16AB) and dye molecule Congo red (CR) via ionic self‐assembly strategy exhibits double stimuli‐responsive behavior triggered by redox and pH value. Both the fabrication and switching mechanism of aggregates are proposed according to the cooperative binding of noncovalent interactions, including π‐π stacking, electrostatic interactions, charge transfer interaction, and amphiphilic hydrophobic association. The optimal geometry and energy transfer between monomers and aggregate are studied by means of quantum chemistry calculation and wavefunction analysis, which provides a deep and theoretical understanding for formation mechanism of ionic self‐assemblies. Moreover, the fluorescent switching behavior of assemblies upon pH was studied in detail, which opens the new way for the construction of organic light‐emitting diode (OLED).
A corotational mixed flat shell finite element for the efficient geometrically nonlinear analysis of laminated composite structures
Authors: Liguori Francesco S. , Madeo Antonio
Published: May 2021

A corotational flat shell element for the geometrically nonlinear analysis of laminated composite structures is presented. The element is obtained from the Hellinger–Reissner variational principle with assumed stress and displacement fields. The stress interpolation is derived from the linear elastic solution for symmetric composite materials. The element is isostatic, namely the stress interpolation is ruled by the minimum number of parameters. Displacement and rotation fields are only assumed along the contour of the element. As such, all the operators are efficiently obtained through analytical contour integration. The geometrical nonlinearity is introduced by means of a corotational formulation. The proposed finite element, named MISS‐4c, proves to be locking free and shows no rank defectiveness. A multimodal Koiter's algorithm is used to obtain the initial postbuckling response. Results show good accuracy and high convergence rate in the geometrically nonlinear analysis of composite shell structures.
Comparison study: The effect of unmodified and modified graphene nano‐platelets (GNP) on the mechanical, thermal, and electrical performance of different types of GNP‐filled materials
Authors: Ka Wei Kam , Leng Teh Pei , Keat Yeoh Cheow , Osman Hakimah , Sullivan Martin , Hong Voon Chun , Ying Lim Bee , Rasidi Mohamad Syahmie Mohamad
Published: May 2021

Graphene nano‐platelet (GNP) nano‐fillers were successfully covalently functionalized with carboxylic and epoxide groups as proven by Fourier‐transform infrared spectroscopy. This paper reports the effect of unmodified and modified GNP nano‐fillers on the mechanical, thermal, and electrical performance of GNP‐filled materials. The results show that the mechanical properties of GNP‐filled materials were enhanced with a modified GNP nano‐filler. Among the GNP‐filled materials, the modified epoxy/NR/GNP compatibilized material shows higher flexural and toughness properties. The modified GNP nano‐filler has reduced the thermal stability of the modified compatibilized material. This is because the oxygen‐containing groups (C–O–C and –COOH) on the surfaces of modified GNP nano‐fillers have lower thermal stability; which accelerates the thermal decomposition of the modified material. Modified compatibilized material shows higher electrical conductivity than the unmodified compatibilized material. X‐ray diffraction results proved that d‐spacing of modified GNP nano‐fillers in modified compatibilized material was shortest when compared to unmodified GNP nano‐fillers in unmodified compatibilized material, thus, allowing more electrons to travel at a faster rate through the conductive pathways.
Mental health and health‐related quality of life in preschool‐aged childhood cancer survivors. Results of the prospective cohort study ikidS‐OEVA
Authors: Neu Marie A. , Schlecht Jennifer , Schmidt Martina F. , Robinson Abigale L. , Spix Claudia , Grabow Desiree , Kaatsch Peter , Erdmann Friederike , Faber Jörg , Urschitz Michael S. ,   IkidS Study Group
Published: May 2021

Objectives

Long‐term survivors of childhood cancer are at increased risk for sequelae such as poor mental health (MH) or impaired health‐related quality of life (HrQoL). We aimed to evaluate early adverse effects on MH and HrQoL in young childhood cancer survivors (YCCS) before school entry.

Methods

In a nationwide prospective cohort study, children with cancer other than brain tumors diagnosed at preschool age and completed cancer treatments were identified from the German Childhood Cancer Registry. The comparison group was children of the same age without a cancer diagnosis who participated in the prospective population‐based health survey ikidS. MH problems and HrQoL were assessed by parental versions of the Strengths and Difficulties Questionnaire (SDQ) and the questionnaire for health‐related quality of life in children (KINDL), respectively. Associations between cancer and MH as well as HrQoL were analyzed by multivariable linear regression.

Results

Of 382 YCCS contacted, 145 were enrolled (mean age 6.6 years) and 124 analyzed. Compared to children without a cancer diagnosis (3683 contacted, 2003 enrolled, 1422 analyzed), YCCS had more MH problems (13% vs. 3%) and slightly worse HrQoL (median 78.7 vs. 80.2 points). In the adjusted analysis, YCCS had higher SDQ scores (2.2 points, 95% confidence interval [CI] 1.3, 3.0) and lower KINDL scores (−2.4 points, 95% CI −3.7, −1.1) compared to children without cancer diagnosis.

Conclusion

Already at preschool age, YCCS may be at increased risk of MH problems and impaired HrQoL. This could have impacts on subsequent school performance and educational attainment. Follow‐up health care for YCCS may include early screening for MH problems and reasons for HrQoL deficits.
Validation of coding algorithms for the identification of herpes zoster among children
Authors: Rutstein Beth H. , Gmuca Sabrina , Gerber Jeffrey S. , Lim Tristan , Argraves Melissa , Ogdie Alexis
Published: May 2021

Purpose

To examine the validity of International Classification of Diseases, 10th Revision, (ICD‐10) code‐based algorithms for herpes zoster (HZ) in the electronic medical record (EMR) of a large, integrated pediatric healthcare network and to examine baseline demographics and chronic comorbidities associated with HZ in a representative pediatric population.

Methods

We reviewed the electronic charts of all patients with a single ICD‐10 for HZ (B02.xx) as their primary or secondary diagnosis in the EMR of the Children's Hospital of Philadelphia (CHOP) healthcare network from January 2010–March 2019. The positive predictive value (PPV) for a single code for HZ was calculated and alternative algorithms were examined to determine which method resulted in the highest PPV.

Results

The PPV for a single ICD‐10 code was 91.7% (95% CI 80.8–95.4) for definitive and/or probable cases of HZ and 63.9% (95% CI 53.4%–75.5%) for definitive cases alone. Adding a prescription for an antiviral did not improve the PPV. However, adding a new code for rash entered within 1 week of the HZ code increased the PPV to 100% for definitive and/or probable cases but with substantial loss of sensitivity. A high proportion of children with HZ who required inpatient hospitalization had chronic disease (70%) and were on systemic immunomodulatory therapy (50%).

Conclusions

HZ can be identified with a high PPV in electronic medical records of children using ICD‐10 code alone. These findings lay the foundation for future pharmacoepidemiologic research to better understand risk factors for HZ infection.