bluuebunny/crossref_metadata_2025 huggingface dataset:
Improving the efficacy and reliability of rTMS language mapping by increasing the stimulation frequency
Authors: Nettekoven Charlotte , Pieczewski Julia , Neuschmelting Volker , Jonas Kristina , Goldbrunner Roland , Grefkes Christian , Weiss Lucas Carolin
Published: August 2021

Repetitive TMS (rTMS) with a frequency of 5–10 Hz is widely used for language mapping. However, it may be accompanied by discomfort and is limited in the number and reliability of evoked language errors. We, here, systematically tested the influence of different stimulation frequencies (i.e., 10, 30, and 50 Hz) on tolerability, number, reliability, and cortical distribution of language errors aiming at improved language mapping. 15 right‐handed, healthy subjects (m = 8, median age: 29 yrs) were investigated in two sessions, separated by 2–5 days. In each session, 10, 30, and 50 Hz rTMS were applied over the left hemisphere in a randomized order during a picture naming task. Overall, 30 Hz rTMS evoked significantly more errors (20 ± 12%) compared to 50 Hz (12 ± 8%; p <.01), whereas error rates were comparable between 30/50 and 10 Hz (18 ± 11%). Across all conditions, a significantly higher error rate was found in Session 1 (19 ± 13%) compared to Session 2 (13 ± 7%, p <.05). The error rate was poorly reliable between sessions for 10 (intraclass correlation coefficient, ICC = .315) and 30 Hz (ICC = .427), whereas 50 Hz showed a moderate reliability (ICC = .597). Spatial reliability of language errors was low to moderate with a tendency toward increased reliability for higher frequencies, for example, within frontal regions. Compared to 10 Hz, both, 30 and 50 Hz were rated as less painful. Taken together, our data favor the use of rTMS‐protocols employing higher frequencies for evoking language errors reliably and with reduced discomfort, depending on the region of interest.
Hepatitis E virus RNA‐dependent RNA polymerase is involved in RNA replication and infectious particle production
Authors: Oechslin Noémie , Da Silva Nathalie , Szkolnicka Dagmara , Cantrelle François‐Xavier , Hanoulle Xavier , Moradpour Darius , Gouttenoire Jérôme
Published: August 2021

Background and Aims

Hepatitis E virus (HEV) is one of the most common causes of acute hepatitis worldwide. Its positive‐strand RNA genome encodes three open reading frames (ORF). ORF1 is translated into a large protein composed of multiple domains and is known as the viral replicase. The RNA‐dependent RNA polymerase (RDRP) domain is responsible for the synthesis of viral RNA.

Approach and Results

Here, we identified a highly conserved α‐helix located in the RDRP thumb subdomain. Nuclear magnetic resonance demonstrated an amphipathic α‐helix extending from amino acids 1628 to 1644 of the ORF1 protein. Functional analyses revealed a dual role of this helix in HEV RNA replication and virus production, including assembly and release. Mutations on the hydrophobic side of the amphipathic α‐helix impaired RNA replication and resulted in the selection of a second‐site compensatory change in the RDRP palm subdomain. Other mutations enhanced RNA replication but impaired virus assembly and/or release.

Conclusions

Structure‐function analyses identified a conserved amphipathic α‐helix in the thumb subdomain of the HEV RDRP with a dual role in viral RNA replication and infectious particle production. This study provides structural insights into a key segment of the ORF1 protein and describes the successful use of reverse genetics in HEV, revealing functional interactions between the RDRP thumb and palm subdomains. On a broader scale, it demonstrates that the HEV replicase, similar to those of other positive‐strand RNA viruses, is also involved in virus production.
Interferon drives HCV scarring of the epigenome and creates targetable vulnerabilities following viral clearance
Authors: Hlady Ryan A. , Zhao Xia , El Khoury Louis Y. , Luna Aesis , Pham Kien , Wu Qunfeng , Lee Jeong‐Heon , Pyrsopoulos Nikolaos T. , Liu Chen , Robertson Keith D.
Published: August 2021

Background and Aims

Chronic HCV infection is a leading etiologic driver of cirrhosis and ultimately HCC. Of the approximately 71 million individuals chronically infected with HCV, 10%‐20% are expected to develop severe liver complications in their lifetime. Epigenetic mechanisms including DNA methylation and histone modifications become profoundly disrupted in disease processes including liver disease.

Approach and Results

To understand how HCV infection influences the epigenome and whether these events remain as “scars” following cure of chronic HCV infection, we mapped genome‐wide DNA methylation, four key regulatory histone modifications (H3K4me3, H3K4me1, H3K27ac, and H3K27me3), and open chromatin in parental and HCV‐infected immortalized hepatocytes and the Huh7.5 HCC cell line, along with DNA methylation and gene‐expression analyses following elimination of HCV in these models through treatment with interferon‐α (IFN‐α) or a direct‐acting antiviral (DAA). Our data demonstrate that HCV infection profoundly affects the epigenome (particularly enhancers); HCV shares epigenetic targets with interferon‐α targets; and an overwhelming majority of epigenetic changes induced by HCV remain as “scars” on the epigenome following viral cure. Similar findings are observed in primary human patient samples cured of chronic HCV infection. Supplementation of IFN‐α/DAA antiviral regimens with DNA methyltransferase inhibitor 5‐aza‐2’‐deoxycytidine synergizes in reverting aberrant DNA methylation induced by HCV. Finally, both HCV‐infected and cured cells displayed a blunted immune response, demonstrating a functional effect of epigenetic scarring.

Conclusions

Integration of epigenetic and transcriptional data elucidate key gene deregulation events driven by HCV infection and how this may underpin the long‐term elevated risk for HCC in patients cured of HCV due to epigenome scarring.
Hepatocyte‐specific deletion of adipose triglyceride lipase (adipose triglyceride lipase/patatin‐like phospholipase domain containing 2) ameliorates dietary induced steatohepatitis in mice
Authors: Fuchs Claudia D. , Radun Richard , Dixon Emmanuel D. , Mlitz Veronika , Timelthaler Gerald , Halilbasic Emina , Herac Merima , Jonker Johan W. , Ronda Onne A. H. O. , Tardelli Matteo , Haemmerle Guenter , Zimmermann Robert , Scharnagl Hubert , Stojakovic Tatjana , Verkade Henkjan J. , Trauner Michael
Published: August 2021

Background and Aims

Increased fatty acid (FA) flux from adipose tissue to the liver contributes to the development of NAFLD. Because free FAs are key lipotoxic triggers accelerating disease progression, inhibiting adipose triglyceride lipase (ATGL)/patatin‐like phospholipase domain containing 2 (PNPLA2), the main enzyme driving lipolysis, may attenuate steatohepatitis.

Approach and Results

Hepatocyte‐specific ATGL knockout (ATGL LKO) mice were challenged with methionine‐choline–deficient (MCD) or high‐fat high‐carbohydrate (HFHC) diet. Serum biochemistry, hepatic lipid content and liver histology were assessed. Mechanistically, hepatic gene and protein expression of lipid metabolism, inflammation, fibrosis, apoptosis, and endoplasmic reticulum (ER) stress markers were investigated. DNA binding activity for peroxisome proliferator‐activated receptor (PPAR) α and PPARδ was measured. After short hairpin RNA–mediated ATGL knockdown, HepG2 cells were treated with lipopolysaccharide (LPS) or oleic acid:palmitic acid 2:1 (OP21) to explore the direct role of ATGL in inflammation in vitro. On MCD and HFHC challenge, ATGL LKO mice showed reduced PPARα and increased PPARδ DNA binding activity when compared with challenged wild‐type (WT) mice. Despite histologically and biochemically pronounced hepatic steatosis, dietary‐challenged ATGL LKO mice showed lower hepatic inflammation, reflected by the reduced number of Galectin3/MAC‐2 and myeloperoxidase‐positive cells and low mRNA expression levels of inflammatory markers (such as IL‐1β and F4/80) when compared with WT mice. In line with this, protein levels of the ER stress markers protein kinase R–like endoplasmic reticulum kinase and inositol‐requiring enzyme 1α were reduced in ATGL LKO mice fed with MCD diet. Accordingly, pretreatment of LPS‐treated HepG2 cells with the PPARδ agonist GW0742 suppressed mRNA expression of inflammatory markers. Additionally, ATGL knockdown in HepG2 cells attenuated LPS/OP21‐induced expression of proinflammatory cytokines and chemokines such as chemokine (C‐X‐C motif) ligand 5, chemokine (C‐C motif) ligand (Ccl) 2, and Ccl5.

Conclusions

Low hepatic lipolysis and increased PPARδ activity in ATGL/PNPLA2 deficiency may counteract hepatic inflammation and ER stress despite increased steatosis. Therefore, lowering hepatocyte lipolysis through ATGL inhibition represents a promising therapeutic strategy for the treatment of steatohepatitis.
Assessing job crafting competencies to predict tradeoffs between competing outcomes
Authors: Bruning Patrick F. , Campion Michael A.
Published: August 2021

We introduce the job crafting competency construct and apply it to predict tradeoffs between competing outcomes that are inherent in job crafting, like performance and well‐being or engagement and withdrawal. Job crafting competencies are the clusters of individual knowledge, skills, and abilities that are necessary to achieve personal objectives through effective job crafting problem‐solving. We create a framework of job crafting competencies consisting of comprehensive/simplistic heuristic information use and approach/avoidance problem‐solving skills. In Study 1, we operationalize competencies as profiles demonstrated through an aptitude‐oriented assessment that predicts differences in outcomes. Five distinct profiles emerged in a sample of 174 workers. The high‐volume analytic problem‐solving profile was associated with higher performance and strain, while the ambivalent acquiescence profile was associated with lower performance and strain. The practical problem‐solving profile minimized tradeoffs between performance and strain. Rapid problem‐solving and low‐volume analytic problem‐solving profiles were variants in between these other patterns. Study 2 used a survey of 323 workers to support the uniqueness of the five competencies, and their relationships with approach/avoidance job crafting, engagement, and withdrawal. The research identifies a new job crafting individual difference (job crafting competencies) to delineate outcomes and tradeoffs according to unique competency profiles.
Heat and mass transfer characteristics of double‐diffusive natural convection in a porous annulus: A higher‐order compact approach
Authors: Dutta Sailen , Kalita Jiten C.
Published: August 2021

In this paper, we apply a reconstructed higher‐order compact scheme on nonuniform grids to the problem of double‐diffusive natural convection in a vertical porous annulus. The Darcy model is adopted for the fluid flow coupled with energy and mass equations. Computations are carried out in the regime , , , , and , where is the aspect ratio, is the radius ratio, is the Lewis number, is the buoyancy ratio, and is the thermal Rayleigh number. Extensive computations are carried out to investigate the influence of these parameters on the flow and a general pattern of heat and mass transfer characteristics emerges from the study. Particular attention has been paid to the transient flow behavior while investigating the influence of on the  buoyancy ratio configuration.
Housing Temperature Influences Atypical Antipsychotic Drug‐Induced Bone Loss in Female C57BL/6J Mice
Authors: Kunst Roni F , Langlais Audrie L , Barlow Deborah , Houseknecht Karen L , Motyl Katherine J
Published: August 2021

Atypical antipsychotic (AA) drugs, such as risperidone, are associated with endocrine and metabolic side effects, including impaired bone mineral density (BMD) acquisition and increased fracture risk. We have previously shown that risperidone causes bone loss through the sympathetic nervous system and that bone loss is associated with elevated markers of thermogenesis in brown and white adipose tissue. Because rodents are normally housed in sub‐thermoneutral conditions, we wanted to test whether increasing housing temperature would protect against bone loss from risperidone. Four weeks of risperidone treatment in female C57BL/6J mice at thermoneutral (28°C) housing attenuated risperidone‐induced trabecular bone loss and led to a low‐turnover bone phenotype, with indices of both bone formation and resorption suppressed in mice with risperidone treatment at thermoneutrality, whereas indices of bone resorption were elevated by risperidone at room temperature. Protection against trabecular bone loss was not absolute, however, and additional evidence of cortical bone loss emerged in risperidone‐treated mice at thermoneutrality. Taken together, these findings suggest thermal challenge may be in part responsible for bone loss with risperidone treatment and that housing temperature should be considered when assessing bone outcomes of treatments that impact thermogenic pathways. © 2021 The Authors. JBMR Plus published by Wiley Periodicals LLC on behalf of American Society for Bone and Mineral Research.
Synthesis of activated carbon from hydrothermally carbonized tamarind seeds for lipase immobilization: characterization and application in aroma ester synthesis
Authors: Gonçalves Gabriel RF , Gandolfi Olga RR , Bonomo Renata Cristina F , Fontan Rafael da Costa Ilhéu , Veloso Cristiane M
Published: August 2021

BACKGROUND

This study aimed to evaluate the effect of hydrothermal carbonization on the activated carbons properties of tamarind seeds, which were used as a support in porcine pancreatic lipase (PPL) immobilization, and to evaluate the biocatalyst in the butyl butyrate synthesis.

RESULTS

The activated carbon from hydrochar (ACHT) had oxygen functional groups content about 32.5% higher and a lower point of zero charge (4.42) when compared to those obtained from crude bran (ACT). Differences in textural properties were also observed, with an average pore diameter of 3.20 and 6.46 nm for ACHT and ACT, respectively. The optimal immobilization pH was 5.0, resulting in enzyme loading of 71.8 ± 1.42 mg.g1 and 53.03 ± 0.31 mg·g−1, and in a hydrolytic activity of 222.47 ± 2.80 U·g−1 and 257.18 ± 7.31 U·g−1 for ACT and ACHT, respectively. The addition of Triton X‐100 0.025 w·v−1 to the immobilization buffer led to an increase in ~7% of the hydrolytic activity. The PPL immobilized in pH 5.0 was used in the butyl butyrate synthesis, using a mixture of butanol (240 mmol L−1) and butyric acid (120 mmol L−1), with an esterification yield of ±83% after 4 h of reaction at 40 °C.

CONCLUSION

The PPL immobilized on ACHT showed a small decrease in activity over time, with a residual esterification yield of 84% after 4 cycles of reuse. The present results suggest that the supported biocatalyst has the potential to be used in aqueous and organic media, such as hydrolytic lipid reactions and aroma synthesis mostly used in the food industry. © 2021 Society of Chemical Industry (SCI).
The influence of glycosaminoglycan proteoglycan side chains on tensile force transmission and the nanostructural properties of Achilles tendons
Authors: Al Makhzoomi Anas K. , Kirk Thomas B. , Dye Danielle E. , Allison Garry T.
Published: August 2021

This study investigates the nanostructural mechanisms that lie behind load transmission in tendons and the role of glycosaminoglycans (GAGs) in the transmission of force in the tendon extracellular matrix. The GAGs in white New Zealand rabbit Achilles tendons were enzymatically depleted, and the tendons subjected to cyclic loading at 6% strain for up to 2 hr. A nanoscale morphometric assessment of fibril deformation under strain was linked with the decline in the tendon macroscale mechanical properties. An atomic force microscope (AFM) was employed to characterize the D‐periodicity within and between fibril bundles (WFB and BFB, respectively). By the end of the second hour of the applied strain, the WFB and BFB D‐periodicities had significantly increased in the GAG‐depleted group (29% increase compared with 15% for the control, p < .0001). No statistically significant differences were found between WFB and BFB D‐periodicities in either the control or GAG‐depleted groups, suggesting that mechanical load in Achilles tendons is uniformly distributed and fairly homogenous among the WFB and BFB networks. The results of this study have provided evidence of a cycle‐dependent mechanism of damage accumulation. The accurate quantification of fibril elongation (measured as the WFB and BFB D‐periodicity lengths) in response to macroscopic applied strain has assisted in assessing the complex structure–function relationship in Achilles tendon.
Comparison of k‐wire insertion using oscillatory and unidirectional drilling modes under constant thrust force
Authors: Chen Lei , Li Annie D. R. , Symonds Christopher , Holmes James R. , Weick Jack W.
Published: August 2021

Heat generation during the Kirschner wire (K‐wire) insertion process, under either unidirectional or oscillatory drilling mode, places bone at risk of thermal osteonecrosis which can lead to infection. There is a lack of quantitative understanding of the heat generation difference between the two drilling modes and knowledge of optimal thrust force level under each mode is missing. The goal of this study is to investigate the effects of drilling modes and thrust force levels on the bone drilling outcomes. Controlled machine‐based constant thrust force K‐wire insertion experiments were conducted with key process parameters monitored and compared quantitatively. Statistical analysis showed that the oscillatory mode consumed 2.6 times more electricity than the unidirectional mode but generated 53% less thermal energy and 23% lower peak temperature. However, the oscillation also led to 18% higher peak torque in the transient drilling stage and 23% shallower drilling depth. The optimal choice of the drilling mode depends on specific surgical needs to minimize bone damage (control of peak temperature vs. exposure time and torque control). Heat generation was dominated by the torque and corresponding rotational power under both modes. To minimize the bone temperature while keeping high drilling speed efficiency, a moderate thrust force is preferred under the unidirectional mode to balance between feed force and compressed debris resistance. For oscillatory mode, a small thrust force to keep the K‐wire engaged with the bone is optimal.
Inhibitory Control Moderates the Intervention Effects of a Preventive Parenting Program on Posttraumatic Stress Disorder Symptoms Among Male Service Members
Authors: Zhang Jingchen , Buchanan Gretchen J. R. , Monn Amy R. , Gewirtz Abigail H.
Published: August 2021

Military servicemembers face substantial challenges due to war‐related trauma exposure, including posttraumatic stress disorder (PTSD). Individuals with deficits in inhibitory control (IC) may have an increased risk of developing PTSD due to a reduced ability to regulate their cognitive responses to and disengage from trauma‐related stimuli. After Deployment, Adaptive Parenting Tools (ADAPT) is a mindfulness‐infused parenting program for military families that has also been found to have crossover effects on parental mental health. The present study examined whether fathers’ IC at baseline affected their response to this emotional skills–focused intervention and further influenced their PTSD symptoms 1 year later. The sample included 282 male National Guard and Reserve (NG/R) service members who had recently been deployed to Iraq or Afghanistan. Fathers were randomly assigned to either the ADAPT program or a control condition, with IC measured at baseline and PTSD symptoms measured at baseline and 1‐year follow‐up. Intent‐to‐treat analyses revealed no significant main effect of the intervention on fathers’ PTSD symptoms. However, fathers’ IC moderated intervention effects on PTSD symptoms, f2 = 0.03. The intervention had more beneficial effects on reducing fathers’ PTSD symptoms for participants with low IC at baseline. These findings are consistent with compensatory effects in the risk moderation hypothesis, which suggests that prevention or intervention programs are more effective for high‐risk subgroups.
Ultrasound of the Lateral Femoral Cutaneous Nerve: A Review of the Literature and Pictorial Essay
Authors: Becciolini Marco , Pivec Christopher , Riegler Georg
Published: August 2021

We review the ultrasound (US) findings in patients who present with meralgia paresthetica (MP). The anatomy of the lateral femoral cutaneous nerve at the level where the nerve exits the pelvis and potential entrapment sites that can lead to MP are discussed. A wide range of pathological cases are presented to help in recognizing the US patterns of MP. Finally, our experience with US‐guided treatment is discussed.
Conservation tillage and organic nutrients management improve soil properties, productivity, and economics of a maize‐vegetable pea system in the Eastern Himalayas
Authors: Singh Raghavendra , Babu Subhash , Avasthe Ravi Kant , Meena Ram Swaroop , Yadav Gulab Singh , Das Anup , Mohapatra Kamal Prasad , Rathore Sanjay Singh , Kumar Amit , Singh Chandu
Published: August 2021

Soil quality restoration and sustainable crop production in the rainfed ecosystem of the Indian Himalayas can be achieved through effective conservation tillage and organic management. Hence, a six‐year (2013 to 2019) study was conducted to quantify the effect of tillage and organic nutrient management on soil properties, productivity, and profitability of the maize‐vegetable pea (Pisum sativum) system. Three tillage practices [conventional (CT), reduced (RT), and no‐till (NT)] and four organic nutrients management practices [(ONM)‐farmyard manure @ 8 Mg ha−1farmers practice (ONM1), 100% recommended dose of nitrogen (RDN) through manures (ONM2), 75% RDN through manures + maize/vegetable pea stover in either of the crops (ONM3), and 50% RDN through manures + maize/vegetable pea stover in either of the crops (ONM4)] were tested. The results indicated that the NT had higher soil organic carbon (SOC, 16.49 g kg−1), available N (354.5 kg ha−1), and lesser bulk density (1.31 Mg m−3) and penetration resistance (1.85 MPa) in comparison with that of CT at 0–10 cm depth. The system productivity under NT was 9.6% higher than that obtained under CT. The ONM3had higher SOC content, plant‐available N, soil microbial biomass carbon (SMBC), and dehydrogenase activity (DHA) than ONM1. The integration of RT‐ONM2enhanced SMBC, DHA, maize, and vegetable pea yield by 27.2%, 35.7%, 38.0%, and 60.3%, respectively, over CT‐ONM1. Thus, the study suggested that the adoption of effective conservation tillage with adequate organic nutrient management has the potential to advance the soil properties and productivity of maize‐vegetable pea system in the Himalayan Region.
Compatibility of a Thermoresponsive and Controlled Release System for Promoting Sinonasal Cilia Regeneration
Authors: Schilling Andrea L. , Carcella Adam R. , Moore John , Zahid Maliha , Lo Cecilia , Wang Eric W. , Lee Stella E. , Little Steven R.
Published: August 2021

The current clinical goal for managing chronic rhinosinusitis (CRS), a heterogenous disease of the paranasal sinuses, is to control inflammation, yet adjunct therapies that promote mucosal regeneration can improve the long‐term health of the upper airways. The small natural openings to the sinuses, however, limit the efficacy of traditional drug delivery methods (i.e., nasal sprays and irrigation). Accordingly, a conformable thermoresponsive and controlled release system (“TEMPS”, Thermogel, Extended‐release Microsphere‐based delivery to the Paranasal Sinuses) is developed. The poly(lactic‐co‐glycolic acid) microsphere component enables the encapsulation of numerous therapeutics, such as retinoic acid (RA), an analog of vitamin A (VA). Studies in CRS patients and preclinical models have shown that aqueous RA or VA gels promoted the differentiation of ciliated cells and improved mucosal healing following repeat applications. In the present study, TEMPS is designed for the controlled release of RA such that a single dose of RA‐TEMPS delivers bioactive drug for at least 30 days. Furthermore, as TEMPS will be in direct contact with sinonasal tissue, its compatibility with ciliated human nasal epithelium is explored. After ex vivo incubation in thermogel for 24 h, cilia motility is maintained, providing evidence that TEMPS can be compatible for application along the sinonasal epithelium.
Recent Advances in Boron Nitride Based Hybrid Polymer Nanocomposites
Authors: Aparna Asok , Sethulekshmi A. S , Jayan Jitha S. , Saritha Appukuttan , Joseph Kuruvilla
Published: August 2021

Boron nitride (BN) is an eminent inorganic compound having many interesting characteristics such as improved oxidation resistance, mechanical strength, good thermal conductivity (TC), higher bandgap, high chemical stability, thermal stability, high hydrophobicity, and electrical insulation. The use of BN as a filler in polymers is a well‐established strategy to tailor the properties of polymer composites. Recent studies depict an interesting urge to reap the synergistic effect of various nanofillers with BN in the form of hybrids. Hence the consolidation of the works on BN based hybrid fillers would definitely attract researchers so that these new filler systems could be transformed into useful polymer nanocomposites in future. This review article focuses on the synthesis and characterization of various boron nitride based hybrids in detail. Moreover, the review also throws light on different BN hybrid reinforced polymer nanocomposites (PNCs) and their thermal, electrical, electronic as well as biomedical applications in a detailed manner. Thus the review anticipates serving as a tool toward understanding the recent trends in the field of boron nitride hybrid based ternary polymer composites.
Perm‐Inspired High‐Performance Soy Protein Isolate and Chicken Feather Keratin‐Based Wood Adhesive without External Crosslinker
Authors: Li Xiaona , Zhou Ying , Li Jiongjiong , Li Kuang , Li Jianzhang
Published: August 2021

Crosslinking modification can effectively improve the water resistance of soy protein isolate (SPI) adhesive, but it often depends on petroleum‐based reagents, violating the concept of green environmental protection. Here, inspired by the breaking and recombination of the disulfide bond in the perm process, a high‐performance wood adhesive is prepared by incorporation of SPI (modified by sodium sulfite to cleave the disulfide bonds of protein chains) and feather keratin (FK, extracted from waste chicken feathers by breaking the disulfide bond) without using any other crosslinkers. The crosslinking reaction occurs by disulfide bonds derived from the sulfhydryl group of FK and SPI. Thus the wet shear strength of the SPI/FK‐20 adhesive is improved from 0.57 to 1.18 MPa, an increment of 107%. This study provides a green strategy to prepare high‐performance protein‐based adhesive from the waste products‐chicken feathers, which will contribute to the development of the environmentally friendly wood adhesive industry.
Intrinsic square functions and commutators on Morrey‐Herz spaces with variable exponents
Authors: Abdalmonem Afif , Scapellato Andrea
Published: August 2021

In this article, we will study the boundedness of intrinsic square functions on the Morrey‐Herz spaces
. The boundedness of commutators generated by
functions and intrinsic square functions is also discussed on the aforementioned Morrey‐Herz spaces.
Extension and validation of a GPU‐Monte Carlo dose engine gDPM for 1.5 T MR‐LINAC online independent dose verification
Authors: Li Yongbao , Ding Shouliang , Wang Bin , Liu Hongdong , Huang Xiaoyan , Song Ting
Published: August 2021

Purpose

To extend and validate the accuracy and efficiency of a graphics processing unit (GPU)‐Monte Carlo dose engine for Elekta Unity 1.5 T Magnetic Resonance‐Linear Accelerator (MR‐LINAC) online independent dose verification.

Methods

Electron/positron propagation physics in a uniform magnetic field was implemented in a previously developed GPU‐Monte Carlo dose engine–gDPM. The dose calculation accuracy in the magnetic field was first evaluated in heterogeneous phantom with EGSnrc. The dose engine was then commissioned to a Unity machine with a virtual two photon‐source model and compared with the Monaco treatment planning system. Fifteen patient plans from five tumor sites were included for the quantification of online dose verification accuracy and efficiency.

Results

The extended gDPM accurately calculated the dose in a 1.5 T external magnetic field and was well matched with EGSnrc. The relative dose difference along central beam axis was less than 0.5% for the homogeneous region in water–lung phantom. The maximum difference was found at the build‐up regions and heterogeneous interfaces, reaching 1.9% and 2.4% for 2 and 6 MeV mono‐energy photon beams, respectively. The root mean square errors for depth–dose fall‐off region were less than 0.2% for all field sizes and presented a good match between gDPM and Monaco GPUMCD. For in‐field profiles, the dose differences were within 1% for cross‐plane and in‐plane directions for all calculated depths except dmax. For penumbra regions, the distance‐to‐agreements between two dose profiles were less than 0.1 cm. For patient plan verification, the maximum relative average dose difference was 1.3%. The gamma passing rates with criteria 3% (2 mm) for dose regions above 20% were between 93% and 98%. gDPM can complete the dose calculation for less than 40 s with 5 × 108 photons on a single NVIDIA GTX‐1080Ti GPU and achieve a statistical uncertainty of 0.5%–1.1% for all evaluated cases.

Conclusions

A GPU‐Monte Carlo package–gDPM was extended and validated for Elekta Unity online plan verification. Its calculation accuracy and efficiency make it suitable for online independent dose verification for MR‐LINAC.
Dosimetry of a novel converging X‐ray source for kilovoltage radiotherapy
Authors: Stalbaum Tyler , Partain Larry , Weil Michael D. , Kim Joon , Han Jae Y. , Plies Michael J. , Chen Hong , Ziskin Vitaliy , Bazalova‐Carter Magdalena , Song Samuel , Rand Roy , Boyd Douglas
Published: August 2021

Purpose

The objective of this work was to evaluate phantom dosimetry of a novel kilovoltage (kV) X‐ray source, which employs a stationary tungsten anode and a linearly swept scanning electron beam. The source utilizes converging X‐ray collimation along with orthogonal mechanical rotation to distribute surface flux over large area. In this study, this was investigated as a potential solution to fast‐falloff limitations expected with kV radiotherapy. This was done with the aim of future clinical development of a lower cost radiotherapy alternative to megavoltage (MV) linac systems.

Methods

Radiochromic film was employed for dosimetry on the kV X‐ray source of the linear‐converging radiotherapy system (LCRS). The source utilizes charge particle optics to magnetically deflect and focus an electron beam along a stationary, reflection tungsten target in an ultra‐high‐vacuum stainless‐steel chamber. Resulting X‐rays were collimated into converging beamlets that span a large planar angle and converge at the system isocenter. In this study, radiochromic film dosimetry was done at 140 and 145 kVp for a designated planning treatment volume (PTV) of 4 cm diameter. An acrylic phantom was employed for dose distribution measurements of stationary and rotational delivery. Film dosimetry was evaluated in planes parallel to the source X‐ray window at various depths, as well as in the plane of gantry rotation.

Results

At 140 and 145 kVp and using a collimated 4 cm square field at depth, lesion‐to‐skin dose ratio was shown to improve with additional beams from different relative source positions, where the different beams are focused at the same isocenter and do not overlap at the phantom surface. It was only possible to achieve a 1:1 Dmax‐to‐surface ratio with four delivery beams, but the ratio improved to 4:1 with 12 beams, focused at the same isocenter depth of 7.8 cm in an acrylic phantom. For the tests conducted, the following Dmax‐to‐surface ratios were obtained: 0.4:1 lesion‐to‐skin ratio for stationary delivery from one entry beam, 0.71:1 lesion‐to‐skin ratio was obtained for two beams, 1.07:1 ratio for four beams, and 4:1 for 12 beams. Dose‐depth profiles were evaluated for stationary and rotational dosimetry. Additionally, rotational dosimetry was measured for a case more analogous to a clinical scenario, where the isocenter was located at an off‐center simulated lesion.

Conclusions

The results demonstrate potential dose‐depth improvements with kV arc therapy by distributing the surface flux with a wide converging beam along with perpendicular mechanical source rotation of the LCRS. The system delivered tolerable dose to a large surface area when a threshold of multiple, separated beams was reached. The radiochromic film data support the feasibility of the construct of the LCRS kV radiotherapy system design.
Scout accelerated motion estimation and reduction (SAMER)
Authors: Polak Daniel , Splitthoff Daniel Nicolas , Clifford Bryan , Lo Wei‐Ching , Huang Susie Y. , Conklin John , Wald Lawrence L. , Setsompop Kawin , Cauley Stephen
Published: August 2021

Purpose

To demonstrate a navigator/tracking‐free retrospective motion estimation technique that facilitates clinically acceptable reconstruction time.

Methods

Scout accelerated motion estimation and reduction (SAMER) uses a single 3‐5 s, low‐resolution scout scan and a novel sequence reordering to independently determine motion states by minimizing the data‐consistency error in a SENSE plus motion forward model. This eliminates time‐consuming alternating optimization as no updates to the imaging volume are required during the motion estimation. The SAMER approach was assessed quantitatively through extensive simulation and was evaluated in vivo across multiple motion scenarios and clinical imaging contrasts. Finally, SAMER was synergistically combined with advanced encoding (Wave‐CAIPI) to facilitate rapid motion‐free imaging.

Results

The highly accelerated scout provided sufficient information to achieve accurate motion trajectory estimation (accuracy ~0.2 mm or degrees). The novel sequence reordering improved the stability of the motion parameter estimation and image reconstruction while preserving the clinical imaging contrast. Clinically acceptable computation times for the motion estimation (~4 s/shot) are demonstrated through a fully separable (non‐alternating) motion search across the shots. Substantial artifact reduction was demonstrated in vivo as well as corresponding improvement in the quantitative error metric. Finally, the extension of SAMER to Wave‐encoding enabled rapid high‐quality imaging at up to R = 9‐fold acceleration.

Conclusion

SAMER significantly improved the computational scalability for retrospective motion estimation and correction.
Manifold‐based respiratory phase estimation enables motion and distortion correction of free‐breathing cardiac diffusion tensor MRI
Authors: Coll‐Font Jaume , Chen Shi , Eder Robert , Fang Yiling , Han Qiao Joyce , van den Boomen Maaike , Sosnovik David E. , Mekkaoui Choukri , Nguyen Christopher T.
Published: August 2021

Purpose

For in vivo cardiac DTI, breathing motion and B0 field inhomogeneities produce misalignment and geometric distortion in diffusion‐weighted (DW) images acquired with conventional single‐shot EPI. We propose using a dimensionality reduction method to retrospectively estimate the respiratory phase of DW images and facilitate both distortion correction (DisCo) and motion compensation.

Methods

Free‐breathing electrocardiogram‐triggered whole left‐ventricular cardiac DTI using a second‐order motion‐compensated spin echo EPI sequence and alternating directionality of phase encoding blips was performed on 11 healthy volunteers. The respiratory phase of each DW image was estimated after projecting the DW images into a 2D space with Laplacian eigenmaps. DisCo and motion compensation were applied to the respiratory sorted DW images. The results were compared against conventional breath‐held T2 half‐Fourier single shot turbo spin echo. Cardiac DTI parameters including fractional anisotropy, mean diffusivity, and helix angle transmurality were compared with and without DisCo.

Results

The left‐ventricular geometries after DisCo and motion compensation resulted in significantly improved alignment of DW images with T2 reference. DisCo reduced the distance between the left‐ventricular contours by 13.2% ± 19.2%, P < .05 (2.0 ± 0.4 for DisCo and 2.4 ± 0.5 mm for uncorrected). DisCo DTI parameter maps yielded no significant differences (mean diffusivity: 1.55 ± 0.13 × 10−3 mm2/s and 1.53 ± 0.13 × 10−3 mm2/s, P = .09; fractional anisotropy: 0.375 ± 0.041 and 0.379 ± 0.045, P = .11; helix angle transmurality: 1.00% ± 0.10°/% and 0.99% ± 0.12°/%, P = .44), although the orientation of individual tensors differed.

Conclusion

Retrospective respiratory phase estimation with LE‐based DisCo and motion compensation in free‐breathing cardiac DTI resulting in significantly reduced geometric distortion and improved alignment within and across slices.
Joint total variation‐based reconstruction of multiparametric magnetic resonance images for mapping tissue types
Authors: Pandey Shraddha , Snider A. David , Moreno Wilfrido A. , Ravi Harshan , Bilgin Ali , Raghunand Natarajan
Published: August 2021

Multispectral analysis of coregistered multiparametric magnetic resonance (MR) images provides a powerful method for tissue phenotyping and segmentation. Acquisition of a sufficiently varied set of multicontrast MR images and parameter maps to objectively define multiple normal and pathologic tissue types can require long scan times. Accelerated MRI on clinical scanners with multichannel receivers exploits techniques such as parallel imaging, while accelerated preclinical MRI scanning must rely on alternate approaches. In this work, tumor‐bearing mice were imaged at 7 T to acquire k‐space data corresponding to a series of images with varying T1‐, T2‐ and T2*‐weighting. A joint reconstruction framework is proposed to reconstruct a series of T1‐weighted images and corresponding T1 maps simultaneously from undersampled Cartesian k‐space data. The ambiguity introduced by undersampling was resolved by using model‐based constraints and structural information from a reference fully sampled image as the joint total variation prior. This process was repeated to reconstruct T2‐weighted and T2*‐weighted images and corresponding maps of T2 and T2* from undersampled Cartesian k‐space data. Validation of the reconstructed images and parameter maps was carried out by computing tissue‐type maps, as well as maps of the proton density fat fraction (PDFF), proton density water fraction (PDwF), fat relaxation rate (
and water relaxation rate (
from the reconstructed data, and comparing them with ground truth (GT) equivalents. Tissue‐type maps computed using 18% k‐space data were visually similar to GT tissue‐type maps, with dice coefficients ranging from 0.43 to 0.73 for tumor, fluid adipose and muscle tissue types. The mean T1 and T2 values within each tissue type computed using only 18% k‐space data were within 8%–10% of the GT values from fully sampled data. The PDFF and PDwF maps computed using 27% k‐space data were within 3%–15% of GT values and showed good agreement with the expected values for the four tissue types.
Targeting plasma cells with daratumumab aids in the treatment of post‐transplant autoimmune‐like hepatitis
Authors: Epperly Rebecca , Santiago Teresa , Morin Cara E. , Patton Kurt , Deyo Jeff , Eshun John , Triplett Brandon , Sharma Akshay
Published: August 2021

Antibody‐mediated autoimmune‐like hepatitis is a rare and challenging occurrence after hematopoietic cell transplant (HCT). We present the case of a 16‐year‐old male patient with Ph+ ALL who underwent matched sibling donor HCT and developed autoimmune‐like hepatitis after receiving ponatinib for post‐HCT maintenance, evidenced by marked plasma cell infiltrate on liver biopsy. He was successfully treated with steroids and daratumumab, an anti‐CD38‐monoclonal antibody. The dramatic response in this patient warrants expanded investigation of daratumumab for plasma cell‐mediated disorders post‐HCT. It further highlights that identifying mechanisms of immune‐mediated injury can allow for directed therapy and limit exposure to broad immune suppression.
State‐of‐the‐art review on honeycomb sandwich composite structures with an emphasis on filler materials
Authors: Chandrasekaran Navin Kumar , Arunachalam Vasanthanathan
Published: August 2021

Honeycomb sandwich composites are suitable for making structural materials that are mainly characterized by their lightweight and high stiffness strength. The honeycomb structures filled with foam materials or granular materials concerning to the applications enhance the strength and the damping properties. In this paper, an emphasis has been provided for the comprehensive review of response of honeycomb sandwich structures in different conditions, namely, static, dynamic, and damping behaviors with and without filler material from an experimental and finite element simulation perspective. Various applications of honeycomb sandwich composites in different fields are also reviewed in this paper. Potential new directions in honeycomb sandwich composites are also identified in this paper in addition to the current practices. Conclusions and recommendations from different technical papers are reviewed by considering the honeycomb sandwich composites with filler materials. The given area of research seeks more scientific analysis, modeling, and experiments in future structural applications.
An experimental investigation on the flexural and wear properties of multiscale nanoclay/basalt fiber/epoxy composites
Authors: Nazari Ali
Published: August 2021

In this work, multiscale basalt fiber/epoxy composites were fabricated using silane‐modified Na+‐montmorillonite nanoclay, at various contents (0.5, 1, 3, and 5 wt% with respect to the matrix). Flexural and tribological characteristics of the composites were studied. First of all, a silane coupling agent, namely 3‐aminopropyltriethoxysilane (3‐APTS), was applied onto the surface of the nanoclay particles, and then the effects of modified nanoclay on the three‐point bending and wear properties of the basalt fiber/epoxy composites were assessed. Fourier transform infrared spectra indicated that the 3‐APTS coupling agent was successfully grafted onto the surface of the nanoclay particles after modification. The three‐point bending test results demonstrated that the basalt fiber/epoxy composite having 3 wt% modified nanoclay had the highest flexural strength and modulus. On the other hand, the pin‐on‐disk wear test results showed that the multiscale composite containing 5 wt% modified nanoclay had the highest wear resistance. Finally, the fracture and worn surfaces of the specimens were assessed to identify the dominant mechanisms.
The relation of porosity and creep behavior of glass fiber/epoxy composite: Design of experiments approach
Authors: Alves Fillip Cortat , Monticeli Francisco Maciel , Voorwald Herman Jacobus Cornelis , Cioffi Maria Odila Hilário
Published: August 2021

This work aimed to analyze the influence of voids content, morphology (size and shape), and position on the creep behavior of glass/epoxy composites with a reduced number of experiments, applying the design of experiments statistical approach to describe the creep behavior. For this purpose, a three‐dimensional microstructure of the materials is created from the images of X‐ray microtomography. Analysis of variance shows that the temperature contributes 90% to the initial and final creep deformation; meanwhile, stress and porosity act as secondary factors. Void content is responsible for 15% of the composite creep behavior; meantime, the increase of elliptical and irregular porosity decreases creep resistance. The Weibull analytical model combined with surface response methodology (Taguchi approach) proves to be feasible to predict the creep deformation curve with low error.
Factors influencing clinicians' referral or admission decisions for post‐acute stroke or traumatic brain injury rehabilitation: A scoping review
Authors: Lam Wai Shun Priscilla , Bottari Carolina , Dubé Sandra , Grondin Myrian , Swaine Bonnie
Published: August 2021

Demand for post‐acute stroke and traumatic brain injury (TBI) rehabilitation outweighs resource availability. Every day, clinicians face the challenging task of deciding which patient will benefit or not from rehabilitation. The objectives of this scoping review were to map and compare factors reported by clinicians as influencing referral or admission decisions to post‐acute rehabilitation for stroke and TBI patients, to identify most frequently reported factors and those perceived as most influential. We searched four major databases for articles published between 1946 and January 2021. Articles were included if they reported clinicians' perceptions, investigated referral or admission decisions to post‐acute rehabilitation, and focused on patients with stroke or TBI. Twenty articles met inclusion criteria. The International Classification of Functioning, Disability and Health framework was used to guide data extraction and summarizing. Patient‐related factors most frequently reported by clinicians were age, mental status prior to stroke or TBI, and family support. The two latter were ranked among the most influential by clinicians working with stroke patients, whereas age was ranked of low importance. Organizational factors were reported to influence decisions (particularly the availability of post‐acute care services) as well as clinicians' characteristics (eg, knowledge). Moreover, clinicians' prediction of patient outcome ranked among the most important driver of referral or admission decisions by clinicians working with stroke patients. Findings highlight the complex nature of decision‐making regarding patient selection for rehabilitation and provide insight on important factors that frontline clinicians need to consider when having to make rapid decisions in high‐pressured acute care environments.
Clinical predictors of laryngotracheoesophageal clefts and tracheoesophageal fistulae in children with dysphagia
Authors: Mattos Claudia , Phinizy Pelton , Duffy Kimberly L. , Sobol Steven , Piccione Joseph
Published: August 2021

Laryngotracheoesophageal clefts (LTECs) and tracheoesophageal fistulae (TEF) are important structural causes of aspiration requiring bronchoscopy for diagnosis. Determining which children are at greatest risk for LTEC and TEF would enable clinicians to be more selective in performing bronchoscopy.

Methods

Medical records of children aged 0–18 years who underwent flexible and rigid bronchoscopy for evaluation of dysphagia with aspiration were collected and analyzed to identify predictors of LTEC and TEF.

Results

Seventy‐two children age 2 months to 9 years were identified. LTEC was identified in 19 (26%) and TEF was identified in 1 (1.3%). One‐third of the cohort was born preterm (median gestational age 34 weeks). The proportion of LTEC in those born preterm was lower than that of those born full‐term (12% vs. 34%, p = .03). There was no statistically significant difference in LTEC prevalence based on age, midline defects, laryngomalacia, tracheomalacia, history of TEF repair, silent aspiration, or viscosity of barium aspirated during videofluoroscopic swallowing studies. Bronchoalveolar lavage fluid cytology, lipid‐laden macrophage proportions, and culture results were similar among those with and without LTEC.

Conclusion

Children with dysphagia and tracheal aspiration born full‐term are three times more likely to have LTEC than those born preterm. Dysphagia in children with a history of preterm birth is more likely to be functional as opposed to structural, however, LTEC was identified in approximately 10% of these children and must be considered. These results support the role of bronchoscopy in children with dysphagia with tracheal aspiration.