bluuebunny/crossref_metadata_2025 huggingface dataset:
Estimate of decadal‐scale riverbed deformation and bed‐load sediment transport during flood events in the lowermost Mississippi River
Authors: Wu Chia‐Yu , Mossa Joann , Jaeger John M.
Published: December 2021

Riverbed changes are important to applications in engineering in the environment, such as navigation, salt‐water intrusion and habitat quality. This study employed decadal hydrographic data over the past 50 years (1963–2013), as well as daily water stages and discharges to outline the long‐term channel morphological changes and bed‐load sediments deposited by floods in the lowermost Mississippi River (LMR). To generate accurate bathymetric digital elevation models (DEMs), we interpolated the hydrographic survey in a channel‐centred coordinate system by employing ordinary kriging with anisotropy. Riverbed deformations were estimated by subtracting the elevations between DEMs at two different times to generate a series of DoDs (DEM of difference). The results from DoDs exhibit temporal riverbed change patterns and also reveal net degradation after the completion of the Old River Control Structure in 1963, except for the period 1992–2004. Spatially, over 32% of the total area experienced continuous erosion, with only 0.4% having continuous aggradation. Historical erosion over the past 50 years could be removing the alluvial veneer in sections of the river, and exposing more non‐alluvial sediments, particularly between river kilometre RK 230 and RK 40. Our analysis also shows that riverbed deformation patterns are mainly controlled by flood events, backwater effects, as well as the drawdown effect near the Bonnet Carré spillway. In this study, we also examine whether the LMR traps bed‐load sediment under flood conditions. The probability distribution estimated by Monte Carlo simulation suggests only low amounts of bed‐load sediments are deposited on the channel bed during floods. Spatially, the short‐term bed‐load erosion/deposition pattern roughly matches the decadal‐scale riverbed deformation estimated from DoDs. Moreover, this study finds that the trends between the thalweg changes and riverbed deformation are similar, suggesting that both of these patterns are controlled by the same factors.
Determination of In Vivo Biotransformation Kinetics Using Early-Time Biota Concentrations
Authors: Kuo Dave T. F. , Di Toro Dominic M.
Published: December 2021

Technical challenges have hampered the characterization of biotransformation kinetics—a critical link in understanding and predicting the toxicokinetics and ecotoxicology of organic compounds. A shortcut approach to characterize the in vivo biotransformation rate constant (kM) with incomplete pathway or metabolite details was proposed. The value of kM can be derived as 2tln1fPC(t)), with fPC(t) being the molar equivalent fraction of the parent compound (PC) at an early time t in both constant exposure and decay source chemical uptake scenarios. The approximation-based kM values agreed well with kM values derived from rigorous fitting or toxicokinetic modeling (n = 42, root mean square error = 0.30) with accuracy exceeding those of typical toxicokinetic or partitioning models. The method is accurate when sampling time is adequately resolved (i.e., t < ln(2)/kM) but will likely produce biased kM values with improper time-averaging. The approximate equation yields consistent theoretical expectations for fast and slow biotransformation reactions and is fully compatible with standard bioaccumulation and toxicity testing protocols. The simplification strategy circumvents statistical complications and numerical issues inherent in regressing or modeling the toxicokinetics of multimetabolite systems and may be adapted to similar problems at other physiological scales or ecotoxicological contexts. The method can help advance interspecies comparison of chemical metabolism and support the development of in vitro–in vivo extrapolations and in silico models needed for building next-generation ecological and health risk-assessment practices. Environ Toxicol Chem 2022;41:148–158. © 2021 SETAC
Investigating changes of proteome in the bovine milk serum after retort processing using proteomics techniques
Authors: Wei Zikai , Kang Jiaxin , Liao Minhe , Ju Huanhuan , Fan Rong , Shang Jiaqi , Ning Xuenan , Li Meng
Published: December 2021

The objective of this study was to investigate the changes of the proteins in bovine milk serum after retort processing by label‐free quantification proteomics techniques. A total of 96 and 106 proteins were quantified in control group (CG) and retort group (RG), respectively. Hierarchical clustering analysis of the identified milk serum proteins showed a decrease in the abundance of most proteins, such as serum albumin, lactoperoxidase, lactotransferrin, and complement C3, and an increase in the abundance of other proteins such as κ‐casein, lipocalin 2, and Perilipin. Student's t‐test showed 21 proteins significantly differential abundance between CG and RG (p < .05), of which intensity‐based absolute quantification (iBAQ) of five proteins decreased and iBAQ of 16 proteins increased. Bioinformatics analysis demonstrated that retort processing increased the digestibility of proteins, but this improvement was offset by a decrease in the digestibility of proteins caused by protein modification. Our results provide insight into the proteome of retort sterilized milk for the first time. Given the extremely high security of retort sterilized milk, the proteome of bovine milk serum changes after retort sterilization exposed in this study will contribute to the formula design of retort sterilized milk products.
Option‐implied moments and the cross‐section of stock returns
Authors: Alexiou Lykourgos , Rompolis Leonidas S.
Published: December 2021

We construct a joint score measure using option‐implied volatility, skewness, and kurtosis gauging investors' expectations about favorable future return distribution properties. The high–low decile portfolio formed on this measure earns a statistically significant 0.75% value‐weighted average monthly return. Risk‐adjusted returns are significant and robust when controlling for various characteristics. The positive abnormal return of the spread portfolio can be explained by its exposure to aggregate volatility risk when investors' sentiment is low. When sentiment is high, it is also driven by information flow from the options to the stock market for stocks perceived to be as relatively mispriced.
Dynamic functional connectivity in modular organization of the hippocampal network marks memory phenotypes in temporal lobe epilepsy
Authors: Li Hong , Ding Fang , Chen Cong , Huang Peiyu , Xu Jingjing , Chen Zhong , Wang Shuang , Zhang Minming
Published: December 2021

Temporal lobe epilepsy (TLE) is a network disorder with a high incidence of memory impairment. Memory processing ability highly depends on the dynamic coordination between distinct modules within the hippocampal network. Here, we investigate the relationship between memory phenotypes and modular alterations of dynamic functional connectivity (FC) in the hippocampal network in TLE patients. Then, 31 healthy controls and 66 TLE patients with hippocampal sclerosis were recruited. The patients were classified into memory‐intact (MI, 35 cases) group and memory‐deficit (MD, 31 cases) group, each based on individual's Wechsler Memory Scale‐Revised score. The sliding‐windows approach and graph theory analysis were used to analyze the hippocampal network based on resting state functional magnetic resonance imaging. Temporal properties and modular metrics were calculated. Two discrete and switchable states were revealed: a high modularized state (State I) and a low modularized state (State II), which corresponded to either anterior or posterior hippocampal network dominated pattern. TLE was prone to drive less State I but more State II, and the tendency was more obvious in TLE‐MD. Additionally, TLE‐MD showed more widespread alterations of modular properties compared with TLE‐MI across two states. Furthermore, the dynamic modularity features had unique superiority in discriminating TLE‐MD from TLE‐MI. These findings demonstrated that state transitions and modular function of dissociable hippocampal networks were altered in TLE and more importantly, they could reflect different memory phenotypes. The trend revealed potential values of dynamic FC in elucidating the mechanism underlying memory impairments in TLE.
Moving out but not for the better: Health consequences of interprovincial rural‐urban migration in China
Authors: Shi Xinjie
Published: December 2021

Using panel data from a survey conducted by the Research Center for Rural Economy, this study overcomes the selection bias associated with most health status measures by incorporating dialect proximity as an instrumental variable to evaluate the causal effects of interprovincial migration on individuals' health status in China. The results indicate that, compared to an absorbed category, which includes intraprovincial migration and non‐migration, interprovincial migration worsens health (measured by the self‐reported health status score) by 3%. It is also found that, compared to intraprovincial migrants, interprovincial migrants are more likely to report a lower SHS score, whereas the health effect differences between interprovincial migrants and non‐migrants are insignificant. The study identifies two potential mechanisms that explain this result: (i) The increase in income following migration may improve interprovincial migrants' health, and (ii) the exposure to hazardous working environments worsens health to a significant extent. This finding is also linked to the following gender‐related finding: Compared to women, men are more likely to be employed in heavy industries with hazardous working environments; the negative effects of interprovincial migration on the health status are stronger for men than for women migrants, suggesting that the industry effect dominates.
Effects of adropin on learning and memory in rats tested in the Morris water maze
Authors: Ozkan Ayse , Aslan Mutay Aydin , Sinen Osman , Munzuroglu Mustafa , Derin Narin , Parlak Hande , Bulbul Mehmet , Agar Aysel
Published: December 2021

Adropin is a secreted peptide, which is composed of 43 amino acids and shows an effective role in regulating energy metabolism and insulin resistance. Motor coordination and locomotor activity were improved by adropin in the cerebellum. However, it is not known whether adropin administration has an effect on spatial learning and memory. In this study, we investigated the effect of adropin on spatial learning and memory and characterized the biochemical properties of adropin in the hippocampus. Thirty male Sprague–Dawley rats were randomly divided into two groups as control and adropin groups. The control group received 0.9% NaCl intracerebroventricular for 6 days, while the adropin groups received 1 nmol of adropin dissolved in 0.9% NaCl (for 6 days). The Morris water maze, Y maze, and object location recognition tests were performed to evaluate learning and memory. Also, the locomotor activity tests were measured to assess the motor function. The expression of Akt, phospho‐Akt, CREB, phospho‐CREB, Erk1/2, phospho‐Erk1/2, glycogen synthase kinase 3 β (GSK3β), phospho‐GSK3β, brain‐derived neurotrophic factor (BDNF), and N‐methyl‐d‐aspartate receptor NR2B subunit were determined in the hippocampal tissues by using western blot. Behavior tests showed that adropin significantly increase spatial memory performance. Meanwhile, the western blot analyses revealed that the phosphorylated form of the Akt and CREB were enhanced with adropin administration in the hippocampus. Also, the expression of BDNF showed an enhancement in adropin group in comparison to the control group. In conclusion, we have shown for the first time that adropin exerts its enhancing effect on spatial memory capacity through Akt/CREB/BDNF signaling pathways.
Infant's recognition of three‐dimensional form: Mirror image and structurally distinct objects
Authors: Hawkins Laura , Nyman Tristin M. , Wilcox Teresa
Published: December 2021

This study assessed the extent to which visuospatial processing, as measured by visual scanning behaviour, was associated with infants' ability to recognize mirror image and structurally distinct three‐dimensional objects. Simplified Shepard and Metzler (1971) images were employed. Using a remote eye‐tracker, infants ages 10 to 17 months (n = 130) were familiarized to a target object that rotated 180° around its vertical axis. During test trials, infants saw either the target object or one of two types of novel objects (mirror image or a structurally distinct) rotating through the previously unseen 180°. Infants looked significantly longer at the rotated target than novel object in both the mirror image and structurally distinct condition. However, recognition did not emerge until the third test pair, suggesting that infants found this task difficult task. Analyses revealed a relationship between visual scanning of the novel object during test trials and recognition performance; infants who engaged in focused scanning of the novel object (i.e., attended primarily to the top or bottom of the object) during test trials were more likely to show recognition performance. The results of this experiment identified visual processes that support infants' ability to recognize 3D objects from a previously unseen perspective.
Taylor series‐based deep belief network for automatic classification of diabetic retinopathy using retinal fundus images
Authors: Athalye Saurabh Shrikant , Vijay Gaurav
Published: December 2021

The diagnosis of diabetic retinopathy (DR) disease in the early stage is very important to reduce the risk in DR treatment. Different methods are in practice for detecting the lesions automatically with the retinal image. However, detecting the occurrence of exudates in the macular region poses a challenging task in the computer‐assisted diagnosis of DR. A robust and computationally efficient model for localizing the lesions and features in the retinal fundus image is processed in this research by proposing the Taylor‐based deep belief network (T‐based DBN) classifier. Exudates and their contours are determined based on the blood vessel and optic disc segmentation model. The microaneurysms are detected based on the wavelet model, and the lesions are segmented with the thresholding and binarization approach. The proposed T‐based DBN is highly effective in classifying the DR, based on the multiple layers associated with the restricted Boltzmann machines (RBM) and multi‐layer perceptron (MLP) layer. The proposed T‐based DBN is the integration of the Taylor series with the DBN classifier. The proposed T‐based DBN produces an accurate detection rate and yields better theoretical error bounds. The performance revealed by the proposed model is evaluated using the metrics, namely specificity, sensitivity, and accuracy, with the values of 90.757%, 92.225%, and 92.122%, respectively.
The effects of selenium on GPX4‐mediated lipid peroxidation and apoptosis in germ cells
Authors: Liu Peiyi , Zhu Jiahui , Yuan Guanxiang , Li Di , Wen Ying , Huang Suli , Lv Ziquan , Guo Yinsheng , Cheng Jinquan
Published: December 2021

Emerging evidence suggests that selenium plays an essential role in sperm maturation. However, the specific signaling pathway by which selenium exerts effect has not been elucidated. To evaluate the effect of selenium on GPX4‐mediated lipid peroxidation and apoptosis in germ cells, selenium deficiency was modeled by culturing GC2‐spd cells in serum‐free medium. Treatment with 0.5‐μM sodium selenite (NaSe) or 5.0‐μM selenomethionine (SeMet) significantly improved the proliferation rate and GPX4 protein expression after selenium deficiency. Moreover, NaSe and SeMet decreased the MDA content and lipid peroxidation. When adenovirus was used to knockdown the expression of the GPX4 gene (shRNA‐GPX4), the early apoptosis rate of the shRNA‐GPX4 cells was significantly higher than that of the EGFP cells. Increased expression of Caspase3 and Bax, as well as MDA content were observed in the shRNA‐GPX4 cells compared with EGFP cells. In further, overexpression of the GPX4 gene (ORF‐GPX4) cells exhibited increased cell proliferation and decreased MDA content. However, there was no significant difference in 12/15‐lox expression both in ORF‐GPX4 cells and shRNA‐GPX4 cells. Conclusively, GPX4 was involved in the regulation of lipid peroxidation and apoptosis in GC2‐spd cells. Selenium played a role in promoting cell proliferation by mediating GPX4. The regulation of GPX4 may occur independently of 12/15‐Lox. These findings confirmed the effect of selenium on spermatogenesis and offered a potential target for treating abnormal semen quality in men.
A longitudinal study investigating the relationships among multicultural receptivity, sense of community, and self‐esteem of Korean adolescents
Authors: Park Hye‐Sook
Published: December 2021

The relative homogeneity in ethnicity and language of native Koreans and their highly competitive lifestyle, especially among adolescents preparing for college, have limited their solidarity with heterogeneous ethnic groups, which may cause problems in this global era. This study uses the Korean Children and Youth Panel Survey to explore the relationships among multicultural receptivity, sense of community, and self‐esteem for Korean adolescents over three time points. For this purpose this study conducted an autoregressive cross‐lagged path analysis, controlling for covariates such as gender, parenting style, peer attachment, and satisfaction with academic achievement. The cross‐lagged effects on each other of self‐esteem and sense of community were positive over time. The cross‐lagged effects on each other of multicultural receptivity and self‐esteem were not statistically significant. The results were less symmetrical for the third pairing: the effects of multicultural receptivity on sense of community were consistently positive, but the effects of sense of community on multicultural receptivity were not statistically significant. To enhance the sense of community, promoting multicultural receptivity and self‐esteem would therefore show good results.
Faculty and dental student knowledge, attitudes, and practices concerning the prescribing of opioids: Informing curricular change
Authors: Schwarz Eli , Replogle Karan , McLemore Kenneth , Kohli Richie
Published: December 2021

Objectives

This study aimed to assess the knowledge, attitudes, and practices surrounding the prescribing of opioids and addiction in a dental school population.

Methods

Predoctoral dental students, residents, and dental faculty were surveyed about their beliefs, awareness, opinions about, and prior training in the prescribing of opioids, current prescribing practices, and confidence with risk mitigation strategies. Demographic information collected included gender, race/ethnicity, faculty/student role, year of birth, and year of graduation.

Results

Responses were received from 220 faculty and students (n = 47 and n = 173, respectively). Both faculty and students agreed that opioids were overprescribed for the treatment of dental pain. A majority of faculty and dental students (DS)3 + DS4 and DS1 + DS2 students expressed no or limited prior training in (1) the approved state opioid guidelines (75%, 79%, and 95%, respectively), (2) the identification/assessment of substance use disorders (68%, 81%, and 92%, respectively), and (3) patient education to accompany the prescribing of opioids (71%, 80%, and 92%, respectively). A majority of faculty reported moderate or extreme confidence in their clinical skills related to the prescribing of opioids (75%), their ability to identify patients with substance use disorders (55%), and their ability to discuss addiction risk and secure storage of opioids (65%). In contrast, DS3 + DS4 and DS1 + DS2 students expressed significantly less confidence and training. Faculty and students agreed that the role of a dentist included risk mitigation, but reported actions did not match their beliefs, reportedly due to lack of time, less confidence, and the assumption that a pharmacist would assume risk mitigation conversations.

Conclusions

A cohesive curriculum across the four predoctoral years is needed focusing on factual knowledge about the prescribing of opioids, safe prescribing, and confidence with patient communication and risk mitigation strategies. In addition, a need for parallel faculty development synchronized with and reinforced by curricular content was identified.
Running of the feathertail glider (Acrobates pygmaeus) on level ground: Gaits
Authors: Makarov Viktor A. , Panyutina Aleksandra A.
Published: December 2021

Gliding is a crucial adaptation to arboreal habitats in several groups of mammals. Along with certain advantages it imposes limitations on the quadrupedal running since it affects the locomotor apparatus. To estimate the impact on quadrupedal running in gliders, the feathertail glider (Acrobates pygmaeus) was chosen considering that the small size allows minor morphological modifications for aerial locomotion. The gaits were studied on horizontal flat substrate which made it possible to compare running technique of the glider with that of terrestrial mammals. In all analyzed plots the footfall sequence was found to be asymmetrical; in most cases the bound was used, in contrast, the gallop occurred only occasionally. The half‐bound with the fore lead, the most usual asymmetrical gait in quadrupedal marsupials, was much less common in A. pygmaeus than the bound; the rare among mammals half‐bound with the hind lead was also found. The bound was not only the most common gait but also the steadiest one; therefore we can conclude that A. pygmaeus uses all other asymmetrical gaits as transitional forms associated with changes in speed, direction, etc. The bound with extended suspension is probably preferred by A. pygmaeus because it most closely resembles gliding by posture.
Nonsignificant trends in COVID‐19 trials: Is there a significance?
Authors: Yakoot Mostafa
Published: December 2021

Highlights

Hundreds of clinical trials have been conducted on already available antiviral drugs or natural/herbal substances to repurpose for the treatment of COVID‐19, but with no conclusively consistent statistically significant positive results.

Remdesvir, for example, is facing a confusing situation, after the two major large multinational studies SOLIDARITY and DisCoVeRy concluded that there are no significant survival benefits.

In this viewpoint article, we claimed that the inconsistent time to initiate antiviral drugs during the course of COVID‐12 studies is the major contributing factor for this dilemma. We explained that patients already on mechanical ventilation at the study baseline are considered from a biologically different population than other severity groups. We provided a simple meta‐meta‐analysis to show how excluding them from statistical analysis could affect the statistical significance and conclusions.
Detailed kinetic study of hydrogen abstraction reactions of triphenylene, benzo[e]pyrene, dibenzo[fg,op]naphtacene, and coronene by H atoms
Authors: Khiri Dorra , Taamalli Sonia , El Bakali Abderrahman , Louis Florent , Ivan Černuśák , Ngo Thi Chinh , Nguyen Thi Le Anh , Dao Duy Quang
Published: December 2021

The thermochemical and dynamics of H‐abstraction reactions by H atoms have been investigated for large polycyclic aromatic hydrocarbons (PAHs) including triphenylene, benzo[e]pyrene, dibenzo[fg,op]naphtacene, and coronene using high‐level ab initio methods, UCCSD(T)‐F12. Highly accurate ground‐state potential energy surfaces were obtained and used to compute reliable kinetic data. The structures and vibrational frequencies of all species involved in these reactions have been calculated using the CAM‐B3LYP/6‐311++G(d,p) level of theory. The thermodynamic and kinetic properties have been computed at both used levels of theories. For each type of site, the rate constants were calculated in the 500–2500 K temperature range. The results demonstrate that the overall rate constants of H‐abstraction reactions from PAHs with H atoms are not sensitive to the PAHs and their structures. An overall rate constant expression for these processes regardless of the size and structure of the PAH considered is proposed: k(T) = 5.53 × 107  ×  T2.19exp(58.09(kJ mol−1)/RT).
Vanishing theorems on complete Riemannian manifold with a parallel 1‐form
Authors: Huang Teng , Tan Qiang
Published: December 2021

In this article, we first consider the L2 Morse–Novikov cohomology on a complete Riemannian manifold M equipped with a parallel 1‐form which includes Vaisman manifold. Based on a vanishing theorem of L2 Morse–Novikov cohomology, we prove that the L2‐harmonic forms on M are identically zero.
Cross‐Linkable Polyion Complex Micelles from Polypept(o)ide‐Based ABC‐Triblock Copolymers for siRNA Delivery
Authors: Capelôa Leon , Yazdi Mina , Zhang Heyang , Chen Xiaobing , Nie Yu , Wagner Ernst , Lächelt Ulrich , Barz Matthias
Published: December 2021

ABC‐type triblock copolymers are a rising platform especially for oligonucleotide delivery as they offer an additional functionality besides the anyhow needed functions of shielding and complexation. The authors present a polypept(o)ide‐based triblock copolymer synthesized by amine‐initiated ring‐opening polymerization (ROP) of N‐carboxyanhydrides (NCAs), comprising a shielding block A of polysarcosine (pSar), a poly(S‐ethylsulfonyl‐l‐cystein) (pCys(SO2Et)) block B for bioreversible and chemo‐selective cross‐linking and a poly(l‐lysine) (pLys) block C for complexation to construct polyion complex (PIC) micelles as vehicle for small interfering RNA (siRNA) delivery. The self‐assembly behavior of ABC‐type triblocks is investigated to derive correlations between block lengths of the polymer and PIC micelle structure, showing an enormous effect of the β‐sheet forming pCys(SO2Et) block. Moreover, the block enables the introduction of disulfide cross‐links by reaction with multifunctional thiols to increase stability against dilution. The right content of the additional block leads to well‐defined cross‐linked 50–60 nm PIC micelles purified from production impurities and determinable siRNA loading. These PIC micelles can deliver functional siRNA into Neuro2A and KB cells evaluated by cellular uptake and specific gene knockdown assays.
Congenital Hypotonia: Cracking a SAGA of consanguineous kindred harboring four genetic variants
Authors: Kalfon Limor , Baydany Meirav , Samra Nadra , Heno Nawaf , Segal Zvi , Eran Ayelet , Yulevich Alon , Fellig Yakov , Mandel Hanna , Falik‐Zaccai Tzipora C.
Published: December 2021

Background

We aimed to determine the molecular and biochemical basis of an extended highly consanguineous family with multiple children presenting severe congenital hypotonia.

Methods

Clinical investigations, homozygosity mapping, linkage analyses and whole exome sequencing, were performed. mRNA and protein levels were determined. Population screening was followed.

Results

We have identified a novel nonsense variant in NGLY1 in two affected siblings, and compound heterozygosity for three novel RYR1 variants in two affected sisters from another nuclear family within the broad pedigree. Population screening revealed a high prevalence of carriers for both diseases. The genetic variants were proven to be pathogenic, as demonstrated by western blot analyses.

Conclusions

Revealing the genetic diagnosis enabled us to provide credible genetic counselling and pre‐natal diagnosis to the extended family and genetic screening for this high‐risk population. Whole exome/genome sequencing should be the first tier tool for accurate determination of the genetic basis of congenital hypotonia. Two different genetic disorders within a large consanguineous pedigree should be always considered.
Von Karman swirling flow of an Oldroyd‐B nanofluid with the influence of activation energy
Authors: Khan Masood , Hafeez Abdul , Ahmed Jawad
Published: December 2021

In this study, the flow of Oldroyd‐B nanofluid caused by a rotating disk is discussed. For the formulation of thermal equation, the Fourier's law of heat conduction is used. The activation energy is also considered here in this study. The flow is generated by a rotating as well as stretching of the disk. The von Karman transformations are introduced to convert the partial differential equations into nondimensional ordinary differential equations. To deal the governing nonlinear ordinary differential equations, we utilized the bvp midrich scheme and acquired the numerical solutions of the problem. The final outcomes are of the graphical forms which are in terms of the velocity fields, temperature, and concentration distributions, respectively.
Asymptotic streamline diffusion finite element method for singularly perturbed convection–diffusion differential difference equations
Authors: L.S. Senthilkumar , Veerasamy Subburayan , Agarwal Ravi P.
Published: December 2021

In this article, we presented an asymptotic streamline diffusion finite element method (SDFEM) for singularly perturbed convection–diffusion‐type differential difference equations. Using the asymptotic expansion approximation, the differential difference equations are converted into nondelay differential equations. A SDFEM is applied to the modified equation. Further, we proved that the method gives an almost second‐order convergence in maximum norm, in L2‐norm whereas first‐order convergence in H1‐norm. Numerical results are presented to validate the theoretical results.
An artificial intelligence‐accelerated 2‐minute multi‐shot echo planar imaging protocol for comprehensive high‐quality clinical brain imaging
Authors: Clifford Bryan , Conklin John , Huang Susie Y. , Feiweier Thorsten , Hosseini Zahra , Goncalves Filho Augusto Lio M. , Tabari Azadeh , Demir Serdest , Lo Wei‐Ching , Longo Maria Gabriela Figueiro , Lev Michael , Schaefer Pam , Rapalino Otto , Setsompop Kawin , Bilgic Berkin , Cauley Stephen
Published: December 2021

Purpose

We introduce and validate an artificial intelligence (AI)‐accelerated multi‐shot echo‐planar imaging (msEPI)‐based method that provides T1w, T2w, , T2‐FLAIR, and DWI images with high SNR, high tissue contrast, low specific absorption rates (SAR), and minimal distortion in 2 minutes.

Methods

The rapid imaging technique combines a novel machine learning (ML) scheme to limit g‐factor noise amplification and improve SNR, a magnetization transfer preparation module to provide clinically desirable contrast, and high per‐shot EPI undersampling factors to reduce distortion. The ML training and image reconstruction incorporates a tunable parameter for controlling the level of denoising/smoothness. The performance of the reconstruction method is evaluated across various acceleration factors, contrasts, and SNR conditions. The 2‐minute protocol is directly compared to a 10‐minute clinical reference protocol through deployment in a clinical setting, where five representative cases with pathology are examined.

Results

Optimization of custom msEPI sequences and protocols was performed to balance acquisition efficiency and image quality compared to the five‐fold longer clinical reference. Training data from 16 healthy subjects across multiple contrasts and orientations were used to produce ML networks at various acceleration levels. The flexibility of the ML reconstruction was demonstrated across SNR levels, and an optimized regularization was determined through radiological review. Network generalization toward novel pathology, unobserved during training, was illustrated in five clinical case studies with clinical reference images provided for comparison.

Conclusion

The rapid 2‐minute msEPI‐based protocol with tunable ML reconstruction allows for advantageous trade‐offs between acquisition speed, SNR, and tissue contrast when compared to the five‐fold slower standard clinical reference exam.
Twenty‐four–channel high‐impedance glove array for hand and wrist MRI at 3T
Authors: Zhang Bei , Wang Bili , Ho Justin , Hodono Shota , Burke Christopher , Lattanzi Riccardo , Vester Markus , Rehner Robert , Sodickson Daniel , Brown Ryan , Cloos Martijn
Published: December 2021

Purpose

To present a novel 3T 24‐channel glove array that enables hand and wrist imaging in varying postures.

Methods

The glove array consists of an inner glove holding the electronics and an outer glove protecting the components. The inner glove consists of four main structures: palm, fingers, wrist, and a flap that rolls over on top. Each structure was constructed out of three layers: a layer of electrostatic discharge flame‐resistant fabric, a layer of scuba neoprene, and a layer of mesh fabric. Lightweight and flexible high impedance coil (HIC) elements were inserted into dedicated tubes sewn into the fabric. Coil elements were deliberately shortened to minimize the matching interface. Siemens Tim 4G technology was used to connect all 24 HIC elements to the scanner with only one plug.

Results

The 24‐channel glove array allows large motion of both wrist and hand while maintaining the SNR needed for high‐resolution imaging.

Conclusion

In this work, a purpose‐built 3T glove array that embeds 24 HIC elements is demonstrated for both hand and wrist imaging. The 24‐channel glove array allows a great range of motion of both the wrist and hand while maintaining a high SNR and providing good theoretical acceleration performance, thus enabling hand and wrist imaging at different postures to extract kinematic information.
Dimension reduction graph‐based sparse subspace clustering for intelligent fault identification of rolling element bearings
Authors: Zhao Le , Yang Shaopu , Liu Yongqiang
Published: December 2021

Sparse subspace clustering (SSC) is a spectral clustering methodology. Since high‐dimensional data are often dispersed over the union of many low‐dimensional subspaces, their representation in a suitable dictionary is sparse. Therefore, SSC is an effective technology for diagnosing mechanical system faults. Its main purpose is to create a representation model that can reveal the real subspace structure of high‐dimensional data, construct a similarity matrix by using the sparse representation coefficients of high‐dimensional data, and then cluster the obtained representation coefficients and similarity matrix in subspace. However, the design of SSC algorithm is based on global expression in which each data point is represented by all possible cluster data points. This leads to nonzero terms in nondiagonal blocks of similar matrices, which reduces the recognition performance of matrices. To improve the clustering ability of SSC for rolling bearing and the robustness of the algorithm in the presence of a large number of background noise, a simultaneous dimensionality reduction subspace clustering technology is provided in this work. Through the feature extraction of envelope signal, the dimension of the feature matrix is reduced by singular value decomposition, and the Euclidean distance between samples is replaced by correlation distance. A dimension reduction graph‐based SSC technology is established. Simulation and bearing data of Western Reserve University show that the proposed algorithm can improve the accuracy and compactness of clustering.
Culiacán: Using Photography to Explore the Space between Idyllic Nostalgia and Historical Materialism
Authors: Valenzuela Félix Jesús E.
Published: December 2021

Photography is a medium used to convey a message, often one for remembering. This essay is an attempt of using photography to capture the idyllic nostalgia at the heart of the immigrant experience while at the same time acknowledging the historical materialism that is often overlooked in remembering a childhood.
Cooperative advertising in social networks with positive externalities
Authors: Liang Dong , Xie Jinxing , Zhu Wanshan , Zhao Xiaobo
Published: December 2021

We study the decisions of a supplier and retailer in a cooperative advertising program to sell divisible products to consumers in a social network with positive externalities. The supplier decides its participation rate, the retailer with a limited budget decides discriminative advertising expenditure for consumers, and consumers decide their purchase levels. In this study, we solve the subgame perfect equilibrium of the game between the supplier, retailer, and consumers. The equilibrium leads to a new demand function of advertising expenditure, which is different from those demand functions typically assumed in existing studies. In the equilibrium, the higher a consumer's network influence quantified by Bonacich centrality, the higher is the retailer's advertising expenditure on the consumer. We characterize the supplier's participation rate by two network‐dependent thresholds. If the retailer's budget level is lower than one threshold or higher than the other, the participation rate will not depend on the network structure. Although both parties' profits and the retailer's advertising expenditure increase with the network density, the supplier's participation rate decreases with it. Finally, the retailer's profits can be improved significantly by exploiting the network information and advertising cooperatively.
Toward efficient polynomial preconditioning for GMRES
Authors: Loe Jennifer A. , Morgan Ronald B.
Published: December 2021

We present a polynomial preconditioner for solving large systems of linear equations. The polynomial is derived from the minimum residual polynomial (the GMRES polynomial) and is more straightforward to compute and implement than many previous polynomial preconditioners. Our current implementation of this polynomial using its roots is naturally more stable than previous methods of computing the same polynomial. We implement further stability control using added roots, and this allows for high degree polynomials. We discuss the effectiveness and challenges of root‐adding and give an additional check for stability. In this article, we study the polynomial preconditioner applied to GMRES; however it could be used with any Krylov solver. This polynomial preconditioning algorithm can dramatically improve convergence for some problems, especially for difficult problems, and can reduce dot products by an even greater margin.
Improved performance of polyimide Cirlex‐based dielectric barrier discharge plasma actuators for flow control
Authors: Nunes‐Pereira João , Rodrigues Frederico Freire , Abdollahzadehsangroudi Mohammadmahdi , Páscoa José Carlos , Lanceros‐Mendez Senentxu
Published: December 2021

Dielectric barrier discharge (DBD) plasma actuators are simple electrohydrodynamic devices, which are able to provide effective aerodynamic control. One of the main components of these devices is the thin dielectric layer, which allows to separate and prevent the arc between the high‐voltage electrodes. Different materials can be used as dielectric layer to reduce the power consumption or boost the flow controlling effect of the actuators. In this context, this report presents a comparative study of two commercial polyimides, Kapton and Cirlex, used as dielectric layer of surface DBD plasma actuators. The electrical, dielectric, mechanical, electromechanical, and thermal properties were obtained to evaluate overall performance. It was verified that Cirlex (8.3 W) consumes less power than Kapton (21.3 W) to generate higher induced flow velocity of ≈3.4 m/s for an input voltage of 11 kVpp and 24 kHz. During one AC cycle at 11 kVpp the charge transferred for Cirlex (70 nC) is lower than for Kapton (100 nC), as well as the dielectric breakdown voltage to ignite the plasma discharge, 1.5 and 2.2 kVpp, respectively. The Cirlex DBD presents a higher voltage operation limit (at least 14 kVpp) and a more regular plasma discharge, which results in a more homogenous thermal profile and temperature distribution during its operation. The Cirlex actuator delivered higher mechanical power (6.2 mW) and achieved higher electromechanical efficiency (0.004%). The polyimide Cirlex proved to be a suitable alternative for Kapton to fabricate DBD plasma actuators for flow control with improved performance.
High‐throughput sequencing of peripheral blood for minimal residual disease monitoring in childhood precursor B‐cell acute lymphoblastic leukemia: A prospective feasibility study
Authors: Bartram Jack , Wright Gary , Adams Stuart , Archer Paul , Brooks Tony , Edwards Darren , Hancock Jerry , Knecht Henrik , Inglott Sarah , Mountjoy Edward , Roynane Marie , Wakeman Stephanie , Moppett John , Hubank Mike , Goulden Nick
Published: December 2021

Background

Minimal residual disease (MRD) measured on end‐of‐induction bone marrow (BM) is the most important biomarker for guiding therapy in pediatric acute lymphoblastic leukemia (ALL). Due to limited sensitivity of current approaches, peripheral blood (PB) is not a reliable source for identifying patients needing treatment changes. We sought to determine if high‐throughput sequencing (HTS) (next‐generation sequencing) of rearranged immunoglobulin and T‐cell receptor genes can overcome this and be used to measure MRD in PB.

Procedure

We employed a quantitative HTS approach to accurately measure MRD from one million cell equivalents of DNA from 17 PB samples collected at day 29 after induction therapy in patients with precursor B‐cell ALL. We compared these results to the gold‐standard real‐time PCR result obtained from their paired BM samples, median follow‐up 49 months.

Results

With the increased sensitivity, detecting up to one abnormal cell in a million normal cells, we were able to detect MRD in the PB by HTS in all those patients requiring treatment intensification (MRD ≥ 0.005% in BM).

Conclusion

This is proof of principle that using the increased sensitivity of HTS, PB can be used to measure MRD and stratify children with ALL. The method is cost effective, rapid, accurate, and reproducible, with inherent advantages in children. Importantly, increasing the frequency testing by PB as opposed to intermittent BM sampling may allow extension of the dynamic range of MRD, giving a more complete picture of the kinetics of disease remission while improving relapse prediction and speed of detection.
Resource‐appropriate selection of osteosarcoma treatment protocols in low‐ and middle‐income countries
Authors: Mailankody Sharada , Kumar Venkatesan Sampath , Khan Shah Alam , Banavali Shripad D. , Bajpai Jyoti
Published: December 2021

Osteosarcoma is a rare malignancy; however, it is still the most common primary bone tumor in adolescents and young adults. Chemotherapy improves survival indubitably in osteosarcoma; nevertheless, the concern is the stagnant progress since the last several decades. There are a handful of active agents and unresolved issues, especially in choosing the ideal chemotherapy regimen. The oncology community is in equipoise regarding the position of high‐dose methotrexate (HDMTX), mandatory or adjunct. The choice of therapy becomes widely relevant, including in low‐ and middle‐income countries (LMIC), where HDMTX administration brings additional complexities. Research into novel non‐HDMTX‐based protocols adapted to the available resources is pivotal in improving disease outcomes, especially in LMIC. The current review focuses on real‐world challenges in decision‐making and provides a comprehensive overview of the evolution of treatment protocols in LMIC.
Malignant extracranial germ cell tumours: A first national report by the South African Children's Cancer Study Group
Authors: Hendricks Marc , Cois Annibale , Geel Jennifer , du Plessis Johan , Bassingthwaighte Mairi , Naidu Gita , Rowe Biance , Büchner Ané , Omar Fareed , Thomas Karla , Uys Ronelle , van Zyl Anel , van Heerden Jaques , Mahlachana Ngoakoana , Vermeulen Johani , Davidson Alan , Frazier A. Lindsay , Donald Kirsty , Kruger Mariana
Published: December 2021

Objective

To determine the overall survival (OS) and prognostic factors influencing outcomes in children and adolescents with malignant extracranial germ cell tumours (MEGCTs) in preparation for the development of a harmonised national treatment protocol.

Methods

A retrospective folder review was undertaken at nine South African paediatric oncology units to document patient profiles, tumour and treatment‐related data and outcomes for all children with biopsy‐proven MEGCTs from birth up to and including 16 years of age.

Results

Between 1 January 2000 and 31 December 2015, 218 patients were diagnosed with MEGCTs. Female sex (hazard ratio [HR] 0.284, p = .037) and higher socio‐economic status (SES) (HR 0.071, p = .039) were associated with a significantly lower risk of death. Advanced clinical stage at diagnosis significantly affected 5‐year OS: stage I: 96%; stage II: 94.3%; stage III: 75.5% (p = .017) and stage IV (60.1%; p < .001). There was a significant association between earlier stage at presentation and higher SES (p = .03). Patients with a serum alpha‐fetoprotein (AFP) level of more than 33,000 ng/ml at diagnosis had significantly poorer outcomes (p = .002). The use of chemotherapy significantly improved survival, irrespective of the regimen used (p < .001).

Conclusions

The cohort demonstrated a 5‐year OS of 80.3% with an event‐free survival (EFS) of 75.3%. Stage, the use of chemotherapy and an elevated serum AFP level of more than 33,000 ng/ml were independently predictive of outcome. The relationship between SES and outcome is important as the implementation of the new national protocol hopes to standardise care across the socio‐economic divide.
Evaluation of conductivity and mechanical properties of natural fiber reinforced soy‐melamine formaldehyde based green composite
Authors: Behera Ajaya Kumar , Manna Suvendu
Published: December 2021

This article presents the preparation and characterization of jute‐based green composite using various concentrations of melamine formaldehyde modified soy resin. Highest tensile strength of 62.1 MPa was obtained for 50 wt.% melamine formaldehyde modified soy resin‐based jute‐composite due to formation of synergic bonding between melamine formaldehyde, soy protein and cellulose of jute. Other tensile and flexural properties were also enhanced with increase in melamine formaldehyde content from 0 to 50 wt.%. Storage modulus of developed composite (50 wt.%) was enhanced by 8.48 times as compared to that of soy‐jute composite (0 wt.% melamine formaldehyde). Water absorption of optimum composite was reduced by 45% than that of the normal jute‐soy composite. With increase in melamine formaldehyde content (0–100 wt.%), surface electrical insulation and fire retardance properties of composite were also enhanced drastically. Weight loss data and scanning electron microscopic images of degraded composites after 180 days under soil burial condition revealed that developed composites are bio‐degradable in nature and can replace non‐degradable plastic in different industrial sectors like railway coaches, packaging sector, decorative commodity material, and so on.