bluuebunny/crossref_metadata_2025 huggingface dataset:
Hydrodynamics of an inverse liquid–solid circulating conventional fluidized bed
Authors: Nan Tian , Zhu Jesse
Published: January 2022

An inverse liquid–solid circulating conventional fluidized bed (I‐CCFB) is realized by injecting particles from the top of a conventional liquid–solid fluidized bed (0.076 m ID and 5.4 m height) that is operated in a newly developed circulating conventional fluidization regime located between the conventional and circulating fluidization regimes. The I‐CCFB can achieve a higher solids holdup compared to both conventional and circulating liquid–solid fluidized beds. A new parameter, the bed intensification factor, is defined to quantify the increased solids holdup observed with external solids circulation. The Richardson–Zaki equation is shown to be applicable to the I‐CCFB regime and can be used to correlate the slip velocity and solids holdup, both of which increase with the solids circulation rate. A new flow regime map is presented, including the I‐CCFB and a variety of other liquid–solid fluidized beds.
Geometric Criterion of Topological Phase Transition for Non‐Hermitian Systems
Authors: Fan Annan , Liang Shi‐Dong
Published: January 2022

A geometric criterion of the topological phase transition for non‐Hermitian systems is proposed, based on the length of the boundary of the bulk band in the complex energy plane for non‐Hermitian systems. For 1D systems, it is found that the topological phase transition occurs when the derivatives of the length with respect to parameters are discontinuous. For 2D systems, when the length is discontinuous, the topological phase transitions between the gapped and gapless phases occur. When the derivatives of the length with respect to parameters are discontinuous, the topological phase transition between the gapless and gapless phases occur. These nonanalytic behaviors of the length in the complex energy plane provide a signal to detect the topological phase transitions, which is demonstrated by the 1D non‐Hermitian Su–Schrieffer–Heeger model and the 2D non‐Hermitian Chern insulator model. This geometric criterion provides an efficient insight into the global topological invariant from a geometric local object in the complex energy plane for non‐Hermitian systems.
Direct and Unified Access to Carbon Radicals from Aliphatic Alcohols by Cost‐Efficient Titanium‐Mediated Homolytic C−OH Bond Cleavage
Authors: Suga Takuya , Takahashi Yuuki , Miki Chinatsu , Ukaji Yutaka
Published: January 2022

Low‐valent Ti‐mediated homolytic C−O bond cleavage offers unified access to carbon radicals from ubiquitous non‐activated tertiary, secondary, and even primary alcohols. In contrast to the representative Ti reagents, which were ineffective for this purpose, “TiCl2(cat)”/Zn (cat=catecholate) was found to be specifically active. This method was applied to the addition reactions of radicals to alkenes and exhibited high generality and yields. More than 50 combinations were examined. The excellent cost‐efficiency and accessibility of “TiCl2(cat)”/Zn further enhance its applicability. Control experiments proved the presence of a carbon radical intermediate and excluded the pathway via alkyl chlorides. Further mechanistic study indicated that the 1 : 2 complex of alkoxide (R−O−) and TiIII is an active species in the C−O cleavage.
Fabricating bimodal microcellular structure in polystyrene/carbon nanotube/glass‐fiber hybrid nanocomposite foam by microwave‐assisted heating: A proof‐of‐concept study
Authors: Shahbazi Mehrnaz , Aghvami‐Panah Mohammad , Panahi‐Sarmad Mahyar , Seraji Amir Abbas , Zeraatkar Ali , Ghaffarian Anbaran Reza , Xiao Xueliang
Published: January 2022

In the current study, polystyrene/carbon nanotubes/glass fiber (PS/CNT/GF) hybrid foam with a bimodal cellular‐structure has been fabricated via microwave heating as a novel energy source. Microwave‐assisted (MA) samples not only demonstrated the lowest density as compared to traditional methods but also represented superior compressive mechanical properties. Since the bimodal morphology has not been seen so far, the role of selective microwave heating has been thoroughly investigated from the microstructural point of view. Accordingly, the amount of receiving microwave radiations to heat up the system is controllable via the CNTs (as nucleating agents and absorbers) as well as radiation time. Moreover, 1–15 wt% fibers were incorporated to enhance mechanical performance, which led to turning uniform cellular structure to the bimodal pattern, and its cell morphological was studied thereafter. Electrical conductivity and dielectric permittivity properties have not been deprived of bimodality benefits which have been rigorously proven.
Design, synthesis, in silico ADMET, docking, and antiproliferative evaluations of [1,2,4]triazolo[4,3‐c]quinazolines as classical DNA intercalators
Authors: Alesawy Mohamed S. , Ibrahim Mohamed‐Kamal , Eissa Ibrahim H. , El‐Adl Khaled
Published: January 2022

Eleven novel [1,2,4]triazolo[4,3‐c]quinazolines were designed, synthesized, and evaluated against HepG2 and HCT‐116 cells. The molecular design was performed to investigate the binding mode of the proposed compounds with the DNA active site. The data obtained from biological testing highly correlated with that obtained from molecular modeling. HCT‐116 was found to be the most sensitive cell line to the influence of the new derivatives. In particular, compounds 6f and 6e were found to be the most potent derivatives over all the tested compounds against the two HepG2 and HCT116 cancer cell lines, with IC50 = 23.44 ± 2.9, 12.63 ± 1.2, and 25.80 ± 2.1, and 14.32 ± 1.5 µM, respectively. Although compounds 6f and 6e displayed less activity than doxorubicin (IC50 = 7.94 ± 0.6 and 8.07 ± 0.8 µM, respectively), both could be useful as a template for future design, optimization, and investigation to produce more potent anticancer analogs. The most active derivatives 6a, 6c, 6e, and 6f were evaluated for their DNA‐binding activities. Compound 6f displayed the highest binding affinity. This compound potently intercalates DNA at a decreased IC50 value (54.08 µM). Compounds 6a, 6c, and 6e exhibited good DNA‐binding affinities, with IC50 values of 79.35, 84.08, and 59.35 µM, respectively. Furthermore, ADMET (absorption, distribution, metabolism, excretion, and toxicity) profiles were calculated for the four most active compounds in comparison to doxorubicin as a reference drug. Our derivatives 6a, 6c, 6e, and 6f displayed very good in‐silico‐predicted ADMET profiles. Doxorubicin violates three of Lipinski's rules, our derivatives 6a, 6c, 6e, and 6f do not violate any rule.
Reactive Extraction of Gallic Acid Using Trioctylamine and Tributyl Phosphate with Natural Oils
Authors: Pandey Shitanshu , Wasewar Kailas S. , Datta Dipaloy , Kumar Sushil
Published: January 2022

Experimental and theoretical perspectives of reactive extraction of gallic acid (GA) from aqueous solutions using tri‐n‐butyl phosphate (TBP) and tri‐n‐octylamine (TOA) as extractant dissolved in three nontoxic natural oils, namely, rice bran oil, sunflower oil, and soybean oil, are investigated. The solvent's extractability is observed in an order of sunflower oil > rice bran oil > soybean oil and rice bran oil > sunflower oil > soybean oil with TOA and TBP, respectively. The theoretical insights of reaction mechanisms for the extraction of GA are estimated in the form of overall equilibrium constants (KE), stoichiometric coefficients (m), individual equilibrium constants (K11, K12, K21), and concentrations (C11, C12, and C21) of various complexes formed between extractant and acid.
Temperature and water activity control in a lipase catalyzed esterification process using nonlinear model predictive control
Authors: Zulkeflee Siti Asyura , Rohman Fakhrony Sholahudin , Sata Suhairi Abdul , Aziz Norashid
Published: January 2022

Controlling the batch esterification process is a difficult task because the kinetics of the process incorporate intrinsic nonlinearity, process uncertainty, and model mismatch. The model predictive control (MPC) was created and used in the lipase‐catalyzed esterification process in this study. The Autoregressive with Exogenous Input (ARX) and Nonlinear Autoregressive with Exogenous Input (NARX) models were embedded in the MPC. The controller's goal is to manipulate the jacket flow rate and air flow rate, respectively, to control reactor temperature and water activity. To identify the best controller performance, the ARX‐MPC and NARX‐MPC parameters of horizon time (P), number of control moves (M), and weighting factor (wk and rk) were tuned in tracking set point. In terms of set point tracking, disturbance rejection, and robustness test, the best‐tuned ARX‐MPC and NARX‐MPC controllers were assessed and compared. Due to smaller integral square error (ISE), quicker settling time, streamlined response, and manipulated variables remaining within their permitted constraints, the NARX‐MPC controller outperformed the ARX‐MPC controller.
Axially Chiral Dodecanuclear Lanthanide Clusters Constructed by “Bottom‐Up” Self‐assembly for Enantioselective Sensing
Authors: Zhao Honglei , Cui Dongxu , Kou Junning , Gao Haijuan , Yu Guanghui , Sun Chunyi , Wang Xinlong , Su Zhongmin
Published: January 2022

Comprehensive Summary

Via the bottom‐up synthetic strategy, we synthesized a pair of dodecanuclear metal clusters of Eu12(C2O4)9(R/S‐BNP)18(EtOH)6(H2O)6·8EtOH·7H2O (complex 2), which represent the largest axial chiral lanthanide metal clusters. In the structure, rare four‐pointed star coordination mode of oxalic acid is reported by this work. In addition, as a fluorescence sensor, the complex 2 exhibits high enantioselectivity for R‐/S‐BINOL‐TF2 (EF = 2.87) and other chiral binaphthyl derivatives.
Proteomic differences among patients with heart failure taking furosemide or torsemide
Authors: Cooper Lauren B. , Bruce Scott , Psotka Mitchell , Mentz Robert , Bell Rachel , Seliger Stephen L. , O'Connor Christopher , deFilippi Christopher
Published: January 2022

Background

Loop diuretics are commonly used for patients with heart failure (HF) but it remains unknown if one loop diuretic is clinically superior.

Hypothesis

Biomarkers and proteomics provide insight to how different loop diuretics may differentially affect outcomes.

Methods

Blood and urine were collected from outpatients with HF who were taking torsemide or furosemide for >30 days. Differences were assessed in cardiac, renal, and inflammatory biomarkers and soluble protein panels using the Olink Cardiovascular III and inflammation panels.

Results

Of 78 subjects, 55 (71%) were treated with furosemide and 23 (29%) with torsemide, and 25 provided a urine sample (15 treated with furosemide, 10 with torsemide). Patients taking torsemide were older (68 vs 64 years) with a lower mean eGFR (46 vs 54 ml/min/1.73 m2), a higher proportion were women (39% vs 24%) and Black (43% vs 27%). In plasma, levels of hs‐cTnT, NT‐proBNP, and hsCRP were not significantly different between groups. In urine, there were significant differences in urinary albumin, β‐2M, and NGAL, with higher levels in the torsemide‐treated patients. Of 184 proteins testing in Olink panels, in plasma, 156 (85%) were higher in patients taking torsemide but none were significantly different after correcting for false discovery.

Conclusions

We show differences in urinary biomarkers but few differences in plasma biomarkers among HF patients on different loop diuretics. Olink technology can detect differences in plasma protein levels from multiple biologic domains. These findings raise the importance of defining differences in mechanisms of action of each diuretic in an appropriately powered study.
Anti‐LINGO‐1 antibody treatment alleviates cognitive deficits and promotes maturation of oligodendrocytes in the hippocampus of APP/PS1 mice
Authors: Yang Hao , Jiang Lin , Zhang Yi , Liang Xin , Tang Jing , He Qi , Luo Yan‐Min , Zhou Chun‐Ni , Zhu Lin , Zhang Shan‐Shan , Xiao Kai , Zhu Pei‐Lin , Wang Jin , Li Yue , Chao Feng‐Lei , Tang Yong
Published: January 2022

Leucine‐rich repeat and immunoglobulin‐like domain‐containing nogo receptor‐interacting protein 1 (LINGO‐1), a negative regulator of oligodendrocyte differentiation and myelination, is associated with cognitive function, and its expression is highly upregulated in Alzheimer's disease (AD) patients. Anti‐LINGO‐1 antibody treatment can effectively antagonize the negative regulatory effect of LINGO‐1. In this study, we aim to assess the effect of anti‐LINGO‐1 antibody treatment on cognition and hippocampal oligodendrocytes in an AD transgenic animal model. First, 10‐month‐old male amyloid‐β (Aβ) protein precursor (APP)/presenilin 1 (PS1) mice were administered anti‐LINGO‐1 antibody for 8 weeks. Then, learning and memory abilities were assessed with the Morris water maze (MWM) and Y‐maze tests, and Aβ deposition and hippocampal oligodendrocytes were investigated by immunohistochemistry, immunofluorescence, and stereology. We found that anti‐LINGO‐1 antibody alleviated the deficits in spatial learning and memory abilities and working and reference memory abilities, decreased the density of LINGO‐1 positive cells, decreased Aβ deposition, significantly increased the number of mature oligodendrocytes and the density of myelin, reversed the abnormal increases in the number of oligodendrocyte lineage cells and the densities of oligodendrocytes precursor cells in APP/PS1 mice. Our results provide evidence that LINGO‐1 might be involved in the process of oligodendrocyte dysmaturity in the hippocampus of AD mice, and that antagonizing LINGO‐1 can alleviate cognitive deficits in APP/PS1 mice and decrease Aβ deposition and promote oligodendrocyte differentiation and maturation in the hippocampus of these mice. Our findings suggest that changes in LINGO‐1 and oligodendrocytes in the hippocampus play important roles in the pathogenesis of AD and that antagonizing LINGO‐1 might be a potential therapeutic strategy for AD.
Mechanochemical C−X/C−H Functionalization: An Alternative Strategic Access to Pharmaceuticals
Authors: Yang Xinjie , Wu Chongyang , Su Weike , Yu Jingbo
Published: January 2022

In the pursuit of clean pharmaceutical production, chemists in medicinal industry require access to new sustainable methodologies to reduce and even eliminate pollution, which is mainly produced by the overuse of organic solvents during chemical synthesis of active pharmaceutical ingredients (APIs). In this context, the solvent‐free/less mechanochemical functionalization of small molecules has gradually emerged as a powerful strategy for the green synthesis and modification of APIs, bioactive compounds, and functional materials. In this review, we present an overview of mechanochemical C−X/C−H functionalization applications to medicinal chemistry, involving cross‐coupling, cross‐dehydrogenative coupling, oxidative coupling (via C−H activation pathway), and direct coupling (via radical pathway) as key steps for the preparation of APIs and bioactive compounds.
Cucurbit[7]uril‐Catalyzed Controllable Pinacol Rearrangement with Activated Hydride Migration
Authors: Jin Ye , Li Min , Liu Mao , Ge Qingmei , Cong Hang , Tao Zhu
Published: January 2022

A selective pinacol rearrangement of hydrobenzoin compounds was established through a heterogeneous catalysis strategy in the presence of cucurbit[7]uril. As an unexpected consequence, the ketone was generated as the sole product with the cucurbit[7]uril‐controlled hydride migration under optimized conditions. The five recycled runs suggested the catalytic activity of the cucurbit[7]uril remained. The experimental analysis and DFT calculation disclosed the important role of supramolecular encapsulation of substrates within the cavity of the macrocyclic host to fix the phenyl groups on hydrobenzoin compounds and trigger the hydride migration, therefore, ketone was the prior product.
A simplified model of oscillating electrolytes
Authors: Akram Wasim , Gupta Amit , Bahga Supreet Singh
Published: January 2022

Unstable electrophoretic transport leading to oscillations in concentration profiles occur in certain electrolyte systems known as oscillating electrolytes whose eigenmobilities are complex valued. The study of the nonlinear behavior of such systems is of great interest but is constrained due to a high degree of complexity in the governing equations. Here we present a simplified model of unstable electrophoretic transport in a binary system that reduces the governing equations to two partial differential equations only and does away with other equations that characterize acid–base dissociation reactions and electroneutrality. We present analytical expressions for electromigration fluxes and validate the model with full nonlinear simulations. The model exhibits similar nonlinear behavior as the actual unstable electrophoretic system under various initial disturbances. For comparison, we also show that similar modeling for a stable system predicts concentration profiles that quantitatively agree with its nonoscillating dynamics. Moreover, the unique feature of electromigration flux in oscillating electrolytes that unfolds from the modeling led us to find an elegant explanation of the instability mechanism. Our theory gives a qualitative understanding of the existence and growth of large oscillation patterns in oscillating electrolytes.
Toward high‐efficiency stable 2D/3D perovskite solar cells by incorporating multifunctional CNT:TiO2 additives into 3D perovskite layer
Authors: Jin Mengqi , Li Huilin , Lou Qiang , Du Qing , Huang Qingsong , Shen Zhitao , Li Fumin , Chen Chong
Published: January 2022

The power conversion efficiency (PCE) of 2D/3D perovskite solar cells (PSCs) is still significantly low compared with 3D PSCs due to the poor charge transport ability of 2D perovskite thin films and a large number of defects in 3D thin films. Herein, to address these two issues, multifunctional TiO2 nanoparticles (NPs)‐modified carbon nanotubes (CNT:TiO2) additives are incorporated into 3D perovskite layer for the first time, and demonstrate three positive effects for CNT:TiO2 material application: firstly, it passivates the defect state of the 3D perovskite layer and enhances the charge mobility of the 3D layer; secondly, its interaction with the 2D film increases the conductivity of the 2D layer and produces the interface polarization electric field to promote the hole extraction. As a consequence, not only the PCE of the optimized 2D/3D PSCs with the CNT:TiO2 is greatly improved to 22.7% from 19.8% of the control PSCs, but also the stability is significantly improved.

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Generation of floor and tertiary response spectra of structures under seismic excitations at multiple supports
Authors: Wang Rui , Xie Wei‐Chau , Pandey Mahesh D.
Published: January 2022

A direct spectra‐to‐spectra method is developed for generating floor response spectra (FRS) for structures under earthquake excitations at multiple supports in terms of ground response spectra (GRS). Only GRS,  “t‐response spectra” (tRS),  and basic modal information of primary structures,  which can be readily obtained from modal analyses,  are needed. FRS are separated into dynamic part and quasi‐static part,  which are combined by a new combination rule FRSMS‐CQC developed using random vibration theory. FRSMS‐CQC can account for the correlations between various components affecting FRS,  that is,  the correlation between the responses of oscillators excited by any two vibration modes,  the correlation between the response of an oscillator excited by a vibration mode and the response of an oscillator mounted directly on a support,  and the correlation between the responses of oscillators mounted on two different supports. In particular,  two special cases,  that is,  excitations in the same direction at two supports being fully correlated and excitations at two supports being uncorrelated,  are considered. The direct method can also be applied to generate tertiary response spectra (TRS) from FRS at multiple supports of secondary structures.

Numerical example of a piping system mounted on different buildings,  which are subjected to tridirectional seismic excitations at the foundation level,  is presented to demonstrate the superiority of the proposed method. It is shown that FRS/TRS determined by time‐history (TH) analysis have large variabilities,  particularly at FRS/TRS peaks. The proposed direct method,  which avoids the deficiencies of time history methods,  is of excellent accuracy,  efficiency,  and simplicity.
Dual Targeting of Angipoietin‐1 and von Willebrand Factor by microRNA‐671‐5p Attenuates Liver Angiogenesis and Fibrosis
Authors: Yang Le , Yue Wenhui , Zhang Hang , Zhang Zhi , Xue Renmin , Dong Chengbin , Liu Fuquan , Chang Na , Yang Lin , Li Liying
Published: January 2022

Angipoietin‐1 (Angpt1) and von Willebrand factor (VWF) are two important angiogenic molecules that can drive pathologic angiogenesis and progression of liver fibrosis in our previous study. MicroRNAs (miRs) participate in a variety of physiological and pathological processes, including angiogenesis. However, the critical miRs targeting Angpt1 or VWF and potential molecular mechanism underlying liver fibrosis–associated angiogenesis is not clear yet. Human liver tissues were obtained from patients with different chronic liver diseases. Mouse models of liver fibrosis were induced by injection of CCl4 or bile duct ligation (BDL) operation. MiR‐671‐5p was predicted to target Angpt1 and VWF from three databases (miRanda, RNA22v2, and miRwalk). MiR‐671‐5p expression was decreased in the fibrotic liver of human and mice, with a negative correlation with the levels of Angpt1, VWF, sphingosine kinase‐1 (SphK1, the rate‐limiting enzyme for sphingosine 1‐phosphate [S1P] formation), transforming growth factor β1 (TGFβ1), hypoxia inducible factor (Hif)1α, Hif2α, and fibrosis markers. Importantly, miR‐671‐5p expression was down‐regulated in fluorescence‐activated cell sorted liver sinusoidal endothelial cells and hepatic stellate cells (HSCs) in CCl4 mice compared with control mice. In vitro miR‐671‐5p expression was also decreased in S1P‐stimulated HSCs and TGFβ1‐activated liver sinusoidal endothelial cells, negatively correlated with Angpt1 and VWF expression. MiR‐671‐5p directly targeted Angpt1 and VWF by luciferase reporter assays. In vivo administration of miR‐671‐5p agomir decreased the messenger RNA and protein levels of Anpgt1 and VWF, and attenuated CCl4‐induced or BDL‐induced liver angiogenesis and fibrosis. Conclusion: We identify the negative regulation of miR‐671‐5p on Angpt1 and VWF and liver fibrosis–associated angiogenesis, which may provide promising targets for the prevention and treatment of liver disease.
The cell cycle‐related genes RHAMM, AURKA, TPX2, PLK1, and PLK4 are associated with the poor prognosis of breast cancer patients
Authors: Kahl Iris , Mense Julian , Finke Christopher , Boller Anna‐Lena , Lorber Clara , Győrffy Balázs , Greve Burkhard , Götte Martin , Espinoza‐Sánchez Nancy A
Published: January 2022

Breast cancer is the third most common type of cancer diagnosed. Cell cycle is a complex but highly organized and controlled process, in which normal cells sense mitogenic growth signals that instruct them to enter and progress through their cell cycle. This process culminates in cell division generating two daughter cells with identical amounts of genetic material. Uncontrolled proliferation is one of the hallmarks of cancer. In this study, we analyzed the expression of the cell cycle‐related genes receptor for hyaluronan (HA)‐mediated motility (RHAMM), AURKA, TPX2, PLK1, and PLK4 and correlated them with the prognosis in a collective of 3952 breast cancer patients. A high messenger RNA expression of all studied genes correlated with a poor prognosis. Stratifying the patients according to the expression of hormonal receptors, we found that in patients with estrogen and progesterone receptor‐positive and human epithelial growth factor receptor 2‐negative tumors, and Luminal A and Luminal B tumors, the expression of the five analyzed genes correlates with worse survival. qPCR analysis of a panel of breast cancer cell lines representative of major molecular subtypes indicated a predominant expression in the luminal subtype. In vitro experiments showed that radiation influences the expression of the five analyzed genes both in luminal and triple‐negative model cell lines. Functional analysis of MDA‐MB‐231 cells showed that small interfering RNA knockdown of PLK4 and TPX2 and pharmacological inhibition of PLK1 had an impact on the cell cycle and colony formation. Looking for a potential upstream regulation by microRNAs, we observed a differential expression of RHAMM, AURKA, TPX2, PLK1, and PLK4 after transfecting the MDA‐MB‐231 cells with three different microRNAs. Survival analysis of miR‐34c‐5p, miR‐375, and miR‐142‐3p showed a different impact on the prognosis of breast cancer patients. Our study suggests that RHAMM, AURKA, TPX2, PLK1, and PLK4 can be used as potential targets for treatment or as a prognostic value in breast cancer patients.
The aborted Whipple: Why, and what happens next?
Authors: Shah Mihir M. , Ajay Pranay S. , Meltzer Rebecca S. , Jajja Mohammad R. , Gullickson Cricket R. , Cardona Kenneth , Russell Maria C. , Sarmiento Juan M. , Maithel Shishir K. , Kooby David A.
Published: January 2022

Background

For patients with periampullary adenocarcinoma (PAC), pancreatoduodenectomy (PD) provides the best survival. Surgery on a subset of patients is aborted during PD. We analyzed these patients.

Methods

Patients who underwent laparotomy for planned PD for PAC were identified (2006–2019). From operative notes, we identified the subset with intraoperative decision to abort. Patient, treatment, and outcome data were analyzed. The subset with pancreatic ductal adenocarcinoma (PDAC) was analyzed for survival.

Results

Only 6.7% (n = 55/819) of cases were aborted. Majority 78% (n = 43) had pathologically‐confirmed diagnoses at time of surgery, and 18.2% (n = 10) received preoperative chemotherapy. Reasons for aborted PD included: distant metastases (65.5%, n = 36) and local invasion (34.5%, n = 19). Of patients with metastatic disease, 75% (n = 27) had liver metastases. Eighty‐nine percent (n = 49) of patients underwent at least one palliative bypass procedure and 81.8% (n = 45) had both gastric and biliary bypass. Patients with computed tomography (CT) scans before surgery more commonly had missed metastatic disease (79.2% CT compared to 54.8% magnetic resonance imaging [MRI], χ2 = 3.54, p = 0.059). In PDAC, 61.4% (n = 27/44) were aborted for metastatic disease and 38.7% (n = 17/44) for local invasion. Median overall survival for all PDAC patients after aborted PD was 334 days.

Conclusion

Majority of pancreatoduodenectomies for periampullary adenocarcinoma are done to completion. Liver metastases is the most common reason for aborting. Preoperative MRI may help identify hepatic metastases.
Identification of time‐dependent potential in a fourth‐order pseudo‐hyperbolic equation from additional measurement
Authors: Huntul M.J. , Tamsir Mohammad , Dhiman Neeraj
Published: January 2022

The objective of this work is to reconstruct, for the first time, numerically the time‐dependent potential coefficient in a fourth‐order pseudo‐hyperbolic equation with initial and boundary conditions from additional measurement as an overdetermination condition. This inverse identification problem is an ill‐posed problem but has a unique solution. For the numerical realization, we apply the Quintic B‐spline (QB‐spline) collocation method to discretize the direct problem and the Tikhonov regularization to find a stable and accurate solution. The resulting nonlinear minimization problem is approximated using the MATLAB optimization toolbox routine lsqnonlin. The obtained numerical results are the evidence of the stable and accurate solutions. The von Neumann stability analysis is also carried out.
Technical note: Air bubble‐induced performance degradation in automatic rectum segmentation from cone‐beam CT
Authors: Zhou Hanyue , Cao Minsong , Ma Martin , Yoon Stephanie , Kishan Amar , Ruan Dan
Published: January 2022

Purpose

Cone‐beam computed tomography (CBCT) is widely used for daily anatomy monitoring and can be a potential source to support adaptation. However, low image quality and artifacts limit CBCT's clinical utility. Peristalsis and air bubbles can cause severe artifacts in pelvic CBCT. We have observed that severe air bubble‐induced Feldkamp artifacts in the rectum may contribute to low automatic segmentation accuracy.

Materials and Methods

In this study, air bubbles within the rectum were extracted and automatic rectum segmentation performance was measured in Dice similarity coefficient (DSC). A Gaussian mixture model (GMM) was used to characterize their correlation, and an expectation‐maximization (EM) approach was used to solve the corresponding parameter estimation and decouple the impact from air bubbles versus other image attributes based on cluster memberships. Postprostatectomy patient data with high variability in air bubble size and shape were used in this study to reveal the regression relationship.

Results

GMM identified two distinct correlative relations between the air‐bubble severity in the rectum and the rectum prediction DSC: one showed strong negative dependency of segmentation performance on air bubble presence, and the other one had mild‐to‐moderate dependency that suggested another group of contributing factors influencing rectum segmentation, such as the inconsistent presence of fiducial seeds and shape extremes.

Conclusion

The presence of severe air bubbles contributes semilinearly to performance degradation in automatic rectum segmentation. A good correction mechanism may boost the accuracy and consistency of pelvic segmentation.
Comparison of voxel S‐value methods for personalized voxel‐based dosimetry of 177Lu‐DOTATATE
Authors: Kim Keon Min , Lee Min Sun , Suh Min Seok , Selvam Haniff Shazwan Muhd Safwan , Tan Teik Hin , Cheon Gi Jeong , Kang Keon Wook , Lee Jae Sung
Published: January 2022

Purpose

Voxel‐based dosimetry is potentially accurate than organ‐based dosimetry because it considers the anatomical variations in each individual and the heterogeneous radioactivity distribution in each organ. Here, voxel‐based dosimetry for 177Lu‐DOTATATE therapy was performed using single and multiple voxel S‐value (VSV) methods and compared with Monte Carlo simulations. To verify these methods, we adopted sequential 177Lu‐DOTATATE single‐photon emission computed tomography and X‐ray computed tomography (SPECT/CT) dataset acquired from Sunway Medical Centre using the major vendor's SPECT/CT scanner (Siemens Symbia Intevo).

Methods

The administered activity of 177Lu‐DOTATATE was 7.99 ± 0.36 GBq. SPECT/CT images were acquired 0.5, 4, 24, and 48 h after injection in Sunway Medical Centre. For the multiple VSV method, VSV kernels of 177Lu in media with various densities were generated by Geant4 Application for Emission Tomography (GATE) simulation first. The second step involved the convolution of the time‐integrated activity map with each kernel to produce medium‐specific dose maps. Third, each medium‐specific dose map was masked using binary medium masks, which were generated from CT‐based density maps. Finally, all masked dose maps were summed to generate the final dose map. VSV methods with four different VSV sets (1, 4, 10, and 20 VSVs) were compared. Voxel‐wise density correction for the single VSV method was also performed. The absorbed doses in the kidneys, bone marrow, and tumors were analyzed, and the relative errors between the VSV and Monte Carlo simulation approaches were estimated. Organ‐based dosimetry using Organ Level INternal Dose Assessment/EXponential Modeling (OLINDA/EXM) was also compared.

Results

The accuracy of the multiple VSV approach increased with the number of dose kernels. The average dose estimation errors of a single VSV with density correction and 20 VSVs were less than 6% in most cases, although organ‐based dosimetry using OLINDA/EXM yielded an error of up to 123%. The advantages of the single VSV method with density correction and the 20 VSVs over organ‐based dosimetry were most evident in bone marrow and bone‐metastatic tumors with heterogeneous medium properties.

Conclusion

The single VSV method with density correction and multiple VSV method with 20 dose kernels enabled fast and accurate radiation dose estimation. Accordingly, voxel‐based dosimetry methods can be useful for managing administration activity and for investigating tumor dose responses to further increase the therapeutic efficacy of 177Lu‐DOTATATE.
Energetic formulation of large‐deformation poroelasticity
Authors: Karimi Mina , Massoudi Mehrdad , Walkington Noel , Pozzi Matteo , Dayal Kaushik
Published: January 2022

The modeling of coupled fluid transport and deformation in a porous medium is essential to predict the various geomechanical process such as CO2 sequestration, hydraulic fracturing, and so on. Current applications of interest, for instance, that include fracturing or damage of the solid phase, require a nonlinear description of the large deformations that can occur. This paper presents a variational energy‐based continuum mechanics framework to model large‐deformation poroelasticity. The approach begins from the total free energy density that is additively composed of the free energy of the components. A variational procedure then provides the balance of momentum, fluid transport balance, and pressure relations. A numerical approach based on finite elements is applied to analyze the behavior of saturated and unsaturated porous media using a nonlinear constitutive model for the solid skeleton. Examples studied include the Terzaghi and Mandel problems; a gas–liquid phase‐changing fluid; multiple immiscible gases; and unsaturated systems where we model injection of fluid into soil. The proposed variational approach can potentially have advantages for numerical methods as well as for combining with data‐driven models in a Bayesian framework.
Event‐triggered H control for Markov jump delayed neural networks with redundant channels
Authors: Xu Yao , Lu Hongqian , Song Xingxing , Zhou Wuneng
Published: January 2022

This article discusses the problem of H control for Markov jump neural networks with time‐varying delay and redundant channels under event‐triggered scheme (ETS). First, considering the limited communication channel capacity of the network system, the ETS is introduced to reduce the network load and improve the network utilization. Second, the technique of redundant channels is employed to improve the successful rate of communication network, and two mutually independent random variables which obey Bernoulli distribution are used to reflect the phenomenon of data dropouts of the main channel and redundant channel, respectively. Third, a sufficient condition with a prescribed H disturbance attenuation performance is derived to ensure the stability of the closed‐loop system. And according to a set of feasible linear matrix inequalities, the co‐design of H controller and ETS is proposed. Finally, two simulation examples are given to prove the feasibility of this article.
Impact of a brief training on motivational interviewing and the 5A's approach on weight‐related counseling practices of pediatricians
Authors: Welsh Jean A. , Lange Samantha J. , Figueroa Janet , Walsh Stephanie , Gooding Holly , Cheung Patricia
Published: January 2022

Background

Pediatric primary healthcare providers are well‐positioned to provide healthy lifestyle and weight management related counseling but many lack training in evidence‐based messages and methods.

Objectives

We assessed the impact of a brief, easy‐to‐access training for pediatric healthcare providers, (the Strong4Life Provider Training), designed to introduce/review current evidence‐based messages and methods and improve healthy weight‐related assessment and counseling practices.

Methods

Following their well‐child visit, a convenience sample of children 12–17 years and parents of children 6–11 years (N = 121) of randomly selected Strong4Life trained (N = 15) and untrained (N = 15) pediatricians were administered a survey designed to assess the frequency, content, and patient satisfaction with weight management‐related counseling provided. Results from parents and patients of trained pediatricians (N = 62) compared to those from parents and patients of untrained pediatricians (n = 59) were compared using chi‐square tests. Generalized estimating equations were used to account for lack of independence among respondents from the same practice. P‐values less than 0.05 were considered to be statistically significant.

Results

Parents/patients of trained pediatricians were more likely than those of an untrained pediatrician to report having been asked about child's consumption of fruit/vegetables, 57 (92%) versus 44 (75%), p = 0.04 and sugary drinks, 50 (81%) versus 29 (49%), p = 0.005, and their readiness for behavior change, 47 (76%) versus 29 (49%), p = 0.005, and to set a behavior change goal, 36 (59%) versus. 23 (40%), p = 0.005. Regardless of training status, physical activity, screen time, and weight status were assessed for most patients, and most were satisfied with the discussion. Few (21%) were asked about barriers to behavior change.
Synergistic effect of polyurethane‐coated carbon fiber and electron beam irradiation on the thermal/mechanical properties and long‐term durability of polyamide‐based thermoplastic composites
Authors: Kim Soo‐Yeon , Gang Ha‐Eun , Park Gyu‐Tae , Jeon Ha‐Bin , Kim Hyun Bin , Oh Seung‐Hwan , Jeong Young Gyu
Published: January 2022

To attain thermoplastic polymer composites with enhanced thermal and mechanical properties as well as long‐term durability, in this study, polyurethane‐coated carbon fiber (CF) and electron beam (EB) irradiation are adopted as an effective reinforcing filler and efficient crosslinking process, respectively. For this purpose, polyamide 6 (PA)‐based composites with different CF contents of 1–10 wt% were fabricated through melt‐compounding and compression molding, and then irradiated with various EB doses of 50–200 kGy. The SEM and FT‐IR data reveal that CFs are well dispersed in the PA matrix with excellent interfacial adhesion via specific intermolecular interactions, which are even enhanced for the composites with crosslinked PA matrices after the EB irradiation. As the result, the thermal stability (initial decomposition temperature and residue at 800°C) and dynamic mechanical properties of PA/CF composites increased noticeably with increasing the CF content and EB irradiation dose. The initial storage modulus of 1.90 GPa for neat PA at 30°C was improved significantly to 2.94 GPa by 10 wt% CF addition and to 4.67 GPa by 200 kGy EB irradiation. In particular, the long‐term mechanical properties of PA/CF composites, which were evaluated using a stepped isothermal method based on the time–temperature superposition principle, were found to be highly enhanced by the synergistic effect of CF filler reinforcement, EB‐induced PA matrix crosslinking, and improved interfacial adhesion.
Development of PPTA/cellulose three‐layer composite insulating paper with low dielectric constant and good mechanical strength based on molecular dynamics simulation
Authors: Mo Yang , Yang Lijun , Yin Fei , Gao Yuanyuan , Liao Ruijin
Published: January 2022

Reducing the dielectric constant of insulating paper to improve the dielectric coordination performance of the oil‐paper systems has always been the research hotspot in the transformer insulation material industry. This paper prepares a novel poly‐p‐phenylene terephthalamide (PPTA)/cellulose composite paper with low dielectric constant and good mechanical properties. Various PPTA/cellulose mixing structures were established and the dielectric and mechanical properties were simulated via molecular dynamics simulation. Results showed that the PPTA/cellulose composite system had a lower dielectric constant than the cellulose system, for adding PPTA molecular could reduce the free volume of the system and limit the steering polarization of the dipole, as well as decrease the system polarization intensity. Constructing a three‐layer structure that contains continuous cellulose middle layer could improve the mechanical properties of the composite system greatly. Experimental results verified the simulation results. The dielectric constant of the three‐layer PPTA/cellulose composite paper decreased from 3.98 to 3.49 at 50 Hz, compared to the conventional cellulose paper. Moreover, the tensile strength of the novel three‐layer PPTA/cellulose composite paper (thickness: 130 μm) has reached 9.02 kN/m, increased by 27.6% than the directly mixed composite paper. Molecular dynamics simulation proves to be a promising method for guiding paper modification. Constructing three‐layer PPTA/cellulose structure represents an effective way to prepare a low dielectric constant composite insulating paper with good mechanical properties.
Effect of manufacturing processes and multi‐walled carbon nanotube loading on mechanical and dynamic properties of glass fiber reinforced composites
Authors: Dhilipkumar Thulasidhas , Rajesh Murugan
Published: January 2022

An effective manufacturing process and high‐performance composite structures are indispensable in the aerospace, automobile, and shipbuilding industries. The current study focuses on the combined effect of carbon nanotube (CNT) reinforcement and manufacturing methods such as co‐curing, co‐bonding, and secondary bonding (SB) on mechanical and free vibrational behavior of glass fiber reinforced plastic composite. Results affirmed that composite fabricated using co‐cure manufacturing method with 1 wt% CNT loading improved the tensile strength by 22.8%, 12.7% compared to co‐bonded and secondary bonded composites due to rougher surface formation over the fiber improved the adhesion between fiber and matrix. On the other hand, 0.25 wt% CNT added secondary bonded composite had the highest (398.19 MPa) flexural strength. The modal analysis asserted that 1 wt% CNT added co‐cured composite beam had the higher fundamental natural frequencies while higher wt% CNT loading enhanced the damping properties owing to higher interaction among fiber and matrix. The current study exposes that mechanical properties and free vibrational characteristics can be improved by selecting the right manufacturing technique and appropriate weight fractions of CNTs. The co‐cure manufacturing with 1 wt% of CNTs and SB with 0.25 wt% of CNTs provided the greatest enhancement to adhesively bonded composites' mechanical properties and dynamics characteristics.
Quality of clinical practice guidelines on interventional management of low back pain: A systematic review
Authors: Olivier Timothy J. , Baltich Nelson Becky , Pham Tri , Trivedi Kavita , Patel Ankit , Sharma G. Sunny , Konda Chaitanya , Annaswamy Thiru M.
Published: January 2022

Objective

To appraise the quality of low back pain (LBP) clinical practice guidelines (CPG) that include interventional management recommendations and to associate their quality with characteristics including publication year and creating organization.

Type

Systematic Review.

Literature Survey

LBP (subacute or chronic) CPGs in English (symptom based, governmental or professional society created, January 1990‐May 2020) were found using MEDLINE, EMBASE, CINAHL, Ortho Guidelines, CPG Infobase, ECRI, Guidelines International Network, NICE, and SIGN.

Methodology

In this third order systematic review, search results were deduplicated, title and abstract screened by two independent reviewers, and full texts reviewed by four reviewers. Discrepancies were resolved by a third reviewer. Resulted CPGs were appraised using the Appraisal of Guidelines for Research and Evaluation (AGREE II) Tool by four appraisers each. Association of their quality with creating organization, geographical region, and year of creation was calculated.

Synthesis

Seven hundred fourteen screened documents resulted in 21 final CPGs. On appraisal, average overall CPG quality was 5.2 (range 2.5‐6.75). Domain 5 (applicability) had the lowest average (44%) and domain 4 (clarity of presentation) had the highest average score (82%). For overall recommendation, 16 received “yes” or “yes with modifications,” six received unanimous “yes” and two unanimous “no” votes. The interrater agreement of domain scoring was excellent (0.8‐1.0; p < .001). There was no association found between quality of CPG and (1) year of publication (R2 = 0.0006), (2) whether the CPG was updated or new (p = .17), and (3) region of publication (p = .37).

Conclusions

The majority of the 21 CPGs identified in this systematic review were of high quality, but overall quality and recommendation ratings were variable. The quality of appraised CPGs showed no association with their characteristics. Some domains such as “applicability” scored uniformly lower, revealing opportunity for improvement in future CPG development. LBP CPGs should be scrutinized before adopting their recommendations.
Robotic assistance is technically superior to conventional laparoscopy in hemicolectomies
Authors: Ngu James Chi‐Yong , Teo Nan‐Zun
Published: January 2022

Objective

An objective assessment of robotic assistance in hemicolectomies.

Background

Robotic assistance has been objectively shown to be superior to conventional laparoscopy in anterior resections. This follow‐up study analyzes the role of robotics in hemicolectomies.

Methods

Operative videos of laparoscopic and robotic hemicolectomies were reviewed. Only oncological resections were included. Two components were evaluated – scope holder performance and assistant instrument performance.

Results

A total of 40 videos were reviewed. The cases were stratified in equal numbers based on method of surgery (robotic, laparoscopic), type of hemicolectomy (right, left), and seniority of the bedside assistant (specialist, non‐specialist). The views achieved in robotic surgery were superior and less dependent on the bedside assistant. The degree of assistance provided by the robotic system was also more than that in the conventional laparoscopic group.

Conclusions

Robotics provides superior visualization and more dynamic assistance than conventional laparoscopy in hemicolectomies. This study demonstrates the technical advantage of robotic assistance, but not necessarily a superiority in clinical outcome.
Resilient and robust control for event‐triggered uncertain semi‐Markov jump systems against stochastic cyber attacks
Authors: Xu Yihao , Zhang Baihai , Chai Senchun , Wang Yanqian
Published: January 2022

This article investigates the problem of event‐based resilient and robust control for semi‐Markov jump systems (S‐MJSs) under stochastic cyber attacks. It is assumed that the uncertain S‐MJS is threaten by stochastic cyber attacks characterized by two different functions. To save the resource of bandwidth limited network, the dynamic event‐triggered (DET) scheme is adopted to reduce the total number of released data through the transmission channel. In addition, the actuator fault, the signal quantization, and the asynchronous phenomenon of the controller are taken into consideration simultaneously, which makes the analysis and synthesis more practical. Based on the linear matrix inequality (LMI) approach, the sufficient conditions are derived to ensure the stochastic stability of the system with a predefined performance. Then the co‐design of resilient controller gains and weighting matrices of the DET scheme is presented in terms of a group of feasible LMIs. Finally, simulation examples are given to validate the proposed method.