bluuebunny/crossref_metadata_2025 huggingface dataset:
Regularized matched-mode processing for source localization
Authors: Collison Nicole E. , Dosso Stan E.
Published: July 2002

This paper develops a new approach to matched-mode processing (MMP) for ocean acoustic source localization. MMP consists of decomposing far-field acoustic data measured at an array of sensors to obtain the excitations of the propagating modes, then matching these with modeled replica excitations computed for a grid of possible source locations. However, modal decomposition can be ill-posed and unstable if the sensor array does not provide an adequate spatial sampling of the acoustic field (i.e., the problem is underdetermined). For such cases, standard decomposition methods yield minimum-norm solutions that are biased towards zero. Although these methods provide a mathematical solution (i.e., a stable solution that fits the data), they may not represent the most physically meaningful solution. The new approach of regularized matched-mode processing (RMMP) carries out an independent modal decomposition prior to comparison with the replica excitations for each grid point, using the replica itself as the a priori estimate in a regularized inversion. For grid points at or near the source location, this should provide a more physically meaningful decomposition; at other points, the procedure provides a stable inversion. In this paper, RMMP is compared to standard MMP and matched-field processing for a series of realistic synthetic test cases, including a variety of noise levels and sensor array configurations, as well as the effects of environmental mismatch.
Simple shear and small amplitude oscillatory rectilinear shear permeation flows of cholesteric liquid crystals
Authors: Rey Alejandro D.
Published: July 2002

A model of rod-like cholesteric liquid crystals subjected to slow steady simple shear and low frequency small amplitude oscillatory shear flow is formulated and applied to permeation flow, also known as Helfrich permeation flow [Helfrich (1969, 1970)], when the cholesteric helix is oriented along the velocity direction and the orientation distortions retain the original planar chiral structure. In permeation flow the elastic forces exactly balance viscous forces. The presence of a small internal length scale (pitch of the helix) leads to boundary layer behavior in the velocity and orientation fields at any shear rate and at any driving frequency. The thickness of the boundary layer region is of the order of the pitch. The apparent viscosity is larger than typical nematic viscosities by a factor proportional to the ratio of the gap thickness to the pitch length. The effect is due to the Ericksen elastic stress. The response of cholesterics to small amplitude oscillatory shear corresponds to a purely viscous material. The out-of-phase stress component vanishes because the viscous force is exactly cancelled by the elastic force. In the terminal region, the loss modulus G″ exhibits a classical frequency ω dependence (G″∝ω) but its magnitude is much greater than for other cholesteric flows by a factor proportional to the ratio of the gap thickness to the pitch length.
Cone angle effects, radial pressure profile, and second normal stress difference for shear-thickening wormlike micelles
Authors: Lee J.-Y. , Magda J. J. , Hu H. , Larson R. G.
Published: July 2002

Many dilute surfactant solutions containing long, thin, wormlike micelles undergo a shear-thickening transition at which the apparent viscosity jumps to a much higher value due to the formation of shear-induced structures. However, the behavior of the normal-stress differences N1 and N2 has not been studied at the low-shear rates and shear stresses (<0.1 Pa) at which shear thickening occurs in most of the commonly studied systems, such as aqueous solutions of cetyltrimethylammonium bromide (CTAB) and sodium salicylate (NaSS). For dilute equimolar solutions of CTAB/NaSS, the validity of measurements of the shear flow properties η, N1 and N2 via cone-and-plate rheometry is assessed by systematically varying the cone angle, and by measuring the pressure profile during cone-and-plate flows. The dependence on the cone angle of the apparent viscosity value is consistent with a stratified fluid structure, as shown to occur in Couette rheometers by Hu and co-workers [Hu, Y. T. et al., J. Rheol. 42, 1209–1226 (1998)]. However, N1 and N2 values show no obvious dependence on cone angle, and the occurrence of flow stratification is surprisingly difficult to detect from the pressure profile. As the shear rate is increased, the measured pressure profiles are suggestive of a gradual transition from viscometric to nonviscometric flow. By combining the results presented here with earlier results by Huang and co-workers [Huang, C.-M. et al., in Proceedings of the XII International Conference on Rheology, edited by A. Ait-Kadi et al. (Canadian Rheology Group, Quebec City, 1996)], we conclude that the same wormy micelle solution exhibits at least two flow transitions that might be described as “shear thickening.” In the shear-rate range of viscometric cone-and-plate flows, the measured normal-stress ratio −N2/N1 for dilute solutions of CTAB/NaSS wormy micelles is similar to the value observed for moderately entangled solutions of synthetic polymers.
Apparent Viscosity of Coarse, Concentrated Suspensions in Tube Flow
Authors: Seshadri V. , Sutera S. P.
Published: July 2002

The apparent viscosity of neutrally buoyant suspensions of rigid spheres and discs in tube flow has been investigated experimentally. Simultaneous measurements of apparent viscosity and the average concentration of particles in the tube were made over wide ranges of concentration (0–45%), tube-to-particle diameter ratio (5 to 114) and tube-Reynolds number (0.4 to 4). The wall-shear stress, determined from pressure-drop data, varied from approximately 1 to 10 dynes/cm2. The results indicate that the most important criterion for the classification of suspension flow is the size of the particles relative to the containing vessel. These experiments show that the tube diameter must be about 50 times the diameter of suspended spheres before the suspension can be treated as a homogeneous fluid whose viscosity is determined effectively by the concentration. At medium concentrations (<30%) and diameter ratios (tube to particle) greater than 10, engineering calculations may be adequately served by taking the relative viscosity to be a function of average concentration in the tube but at an infinite diameter ratio. Tube flows of suspensions exhibit gradual development of an irrotational plug centered on the tube axis. The exact onset of the plug-flow regime depends on both concentration and particle size. With sufficiently large concentration or particle size, or both, the plug-flow region will fill the tube. At that point, particles at the fringe of the plug can be forced into intimate contact with the wall. This condition is accompanied by a noticeable increase in apparent viscosity.
Uniaxial elongational viscosity of high molecular weight high density polyethylene melts (abstract)
Authors: Shinohara Masayuki
Published: July 2002

Extensional properties of high molecular weight high density polyethylene (HDPE) were studied. Uniaxial elongational viscosity was measured under constant strain rate. The following conclusions were obtained. (1) Time-temperature superposition could be applied to the elongational viscosity at a constant strain at different temperatures. (2) The samples which show a remarkable strain-hardening during deformation had a good processability, i.e., narrow distribution of bottle thickness, for the blow molding. (3) Order of the magnitude of steady shear viscosity did not agree with that of maximum elongational viscosity at the same strain rate. (4) Shear relaxation modulus at nonlinear region could not be separated with the terms of strain and modulus during long time period. Transient elongational viscosity calculated was good fit with experimental viscosity behavior by introducing short time process.
Elastic percolation in colloidal dispersions flocculated by polymer bridging (abstract)
Authors: Otsubo Yasufumi
Published: July 2002

The dynamic viscoelasticity was measured for silica dispersions flocculated by polymer bridging. When both the particle and polymer concentrations exceed some critical values, the dispersions respond elastically at low frequencies because a network structure of unbounded flocs is developed over the system. The dispersed particle is compared to the site and the polymer bridge to the bond in the percolation concept. Boundaries for elastic percolation were determined in terms of the site-bond percolation. In bridging flocculation, many bridges are formed by one polymer chain and a series of bridges cannot be broken down to noninteracting bonds. Therefore, the critical probability for bond percolation, pcB, varies with number of bridges formed by one polymer chain, Nb, whereas the critical site probability, pcS, is independent. As a result, scaling analysis is not applicable to the bond process. Flocs in which particles are connected by polymer chains were generated on the computer and pcB was geometrically determined as a function of Nb in a two-dimensional square lattice. For random-bond percolation at Nb=1, the simulation gives the same value as the theoretical prediction, but pcB decreases with increasing Nb. The discrepancy between the experimental results and simulation appears in the Nb dependence of pcB when Nb is large. In strongly interacted systems, the formation of infinite flocs in the geometrical sense does not necessarily lead to the appearance of susceptible elasticity. The fractal dimension of percolating floc decreases with increasing Nb. The elastic properties above the percolation threshold may be closely related to the fractal structure of flocs.
Viscoelastic properties of polymer solutions at temperatures lower than Θ points (abstract)
Authors: Takahashi Yoshiaki , Yamaguchi Masayoshi , Sakakura Daisuke , Noda Ichiro
Published: July 2002

Zero-shear viscosity η0 and steady-state compliance Je of poly(α-methylstyrenes) in benzyl n-butyl phthalate (Θ=4.6 °C) and polystyrene in dioctyl phthalate (Θ=22 °C) were measured at temperatures lower than the Θ points. Moreover, stress developments after onset of steady shear flow were measured and the strength of entanglement was estimated on the basis of network rupture model. The concentration and the molecular weight dependences of η0 at temperatures lower than the Θ points are almost the same as those at the Θ temperatures, but the magnitude of η0 increases with decreasing temperature. This suggests that the strength of entanglement increases with decreasing solvent power. On the other hand, Je values at the temperatures lower than the Θ points are almost the same as those in good and Θ solvents. This result indicates that the entangled structure of polymer solution effective to Je is almost independent of solvent power. Therefore, it is concluded that the gel-like behavior of polymer solution at temperatures lower than the Θ points is caused by the long relaxation times due to the high viscosity.
Numerical simulation on the flow of a viscoelastic fluid through an axisymmetric abrupt contraction−Effect of elongational flow characteristics on vortex and entrance pressure drop (abstract)
Authors: Kajiwara Toshihisa , Kuwano Yoshifumi , Funatsu Kazumori
Published: July 2002

The flow of a viscoelastic fluid through a 4:1 axisymmetric abrupt contraction was studied by means of the finite element method. The effects of elongational viscosity on vortex and entrance pressure drop were investigated in detail using the viscoelastic models which have different values of elongational viscosity by varying the model parameters. The Phan Thien–Tanner (PTT) type and the Giesekus type models with a single relaxation time were used as the constitutive equations. It is found that the vortex grows with the recoverable strain and the model with higher elongational viscosity predicts a larger and more intensive vortex. It seems that the vortex becomes more intensive as recoverable strain becomes larger if elongational viscosity curves coincide. The model with higher elongational viscosity gives larger values for the entrance correction in the PTT type model, while the Giesekus type model gives the opposite prediction. It seems that the magnitude of entrance correction cannot be explained only from the elongational viscosity.
Auto-controlled mechanism for rheological properties of native ovalbumin aqueous colloid (abstract)
Authors: Matsumoto Takayoshi , Chiba Jiro
Published: July 2002

Native ovalbumin (OA) molecules in aqueous colloids are more stable in an ordered arrangement state than in a random dispersion state. Rate of the stabilization from the random dispersion state to the ordered arrangement state is extremely accelerated by shear flow. Isotropic colloids of native OA molecules in buffer solutions show a remarkable yield stress σy and a rigidity G even in very dilute systems such as 0.027 wt. %. The values of σy and G remain almost constant over a wide concentration range from 0.1% to 17%. This suggests that the systems are spontaneously controlled (auto-controlled) in order to suppress the increase in σy and G with increasing concentration of OA. This auto-controlled mechanism disappears completely with gelation by heat denaturation.
Properties of IPNs of epoxy resin/bismaleimide–allylester copolymer (abstract)
Authors: Iisaka Katsuyoshi
Published: July 2002

Interpenetrating polymer networks (IPNs) were prepared from anhydride-cured epoxy resin and bismaleimide (BMI) coreacted with triallyltrimellitate (TAT), triallylisocyanurate (TAIC), and diallylisophthalate (DAP), under the same gelling conditions for both the epoxide resin and BMI–allylester comonomer. Dynamic mechanical properties of the IPNs were measured over the temperature range from room temperature to 400 °C. In addition, tensile and thermal degradation properties were measured for these IPNs. The rubbery modulus and primary dispersion temperature (Tα) due to the cured epoxy resin considerably increased with loading of BMI–allylester component. The value of Tα exhibited an asymptotic behavior at high loading, the value increasing in the order of BMI–TAT, –TAIC, and –DAP. The modulus behavior in the rubber state followed approximately the Budiansky’s equation and suggested the formation of IPN. The difference among the asymptotic values of Tα for each series can be explained in terms of polar-nonpolar solubilities of the components. The most efficient and major increase in Tα which occurred at about 50 wt. % of BMI–allylester component, is based upon an enhanced miscibility between both components as a result of interpenetration. The effects of interpenetration brought about maxima in tensile strength significantly higher than the tensile strength of the component networks and some improvement in thermal resistance at about 50 wt. % of BMI–allylester component.
Some phenomenological relations for strain-induced birefringence of amorphous polymers (abstract)
Authors: Osaki Kunihiro , Inoue Tadashi
Published: July 2002

The strain-induced birefringence of amorphous polymers can be described with the stress-optical rule in the rubbery plateau and the terminal flow zones. This is not the case in the glassy and the glass-to-rubber transition zones. When the stress or the strain is sufficiently small, the birefringence may be described in terms of the linear response theory similar to the linear viscoelasticity theory. In this paper, we present some new relations among the response functions such as the time-dependent stress-optical coefficient and strain-optical coefficient. The birefringence in the following processes were considered: the stress relaxation at constant strain, the creep, the oscillatory deformation, the strain of constant rate, and the subsequent elastic recoil.
The influence of wave dispersion characteristics on the determination of mechanical relaxation spectra
Authors: Williams P. R. , Williams D. J. A.
Published: July 2002

A new rheometrical technique has been developed to determine the mechanical relaxation spectra of viscoelastic materials by measurement of shear wave group and phase velocities in a virtual gap rheometer. The technique’s sensitivity and accuracy in providing relaxation spectra directly from measurements arises from exploitation of marked changes in wave dispersion characteristics in the vicinity of stress relaxation mechanisms. The new technique is compared with two conventional, wave-based rheometrical techniques (based on pulse-propagation and resonance measurements), which are adversely affected by wave dispersion. The superior accuracy and sensitivity of the new technique over conventional rheometry is demonstrated with reference to the Maxwell model and published relaxation spectra. Experimental results obtained on a concentrated colloidal dispersion serve to demonstrate the measurement principles.
Tumbling dynamics in a nematic surfactant solution in transient shear flows
Authors: Caputo Franklin E. , Burghardt Wesley R. , Berret Jean-François
Published: July 2002

We report rheological and structural studies of a nematic surfactant solution (CPCl/hex) in transient shear flows. Upon step changes in steady shear flow conditions, the shear stress exhibits damped oscillations that scale with shear strain, attributed to director tumbling under shear. In situ small-angle x-ray scattering spectroscopy is used to measure changes in average micellar orientation during similar transient shear protocols; the measured orientation parameter also exhibits damped oscillations reflecting the underlying tumbling dynamics. Stress and structure data are compared with predictions of the Larson–Doi tumbling polydomain model. The model predictions are qualitatively similar to the experimental observations. In particular, orientation is observed to initially decrease upon shear flow reversal in CPCl/hex, in agreement with the Larson–Doi predictions but in contrast to previous results for model lyotropic solutions of poly(benzyl glutamate). Shear stress and average orientation are closely related during the oscillatory response to transient flows. The data suggest that higher orientation in the flow direction leads to low instantaneous stresses, and vice versa. The Larson–Doi model does not predict this relationship.
Prostate cancer disease recurrence after radical prostatectomy is associated with HLA type and local cytomegalovirus immunity
Authors: Classon Johanna , Zamboni Margherita , Engblom Camilla , Alkass Kanar , Mantovani Giulia , Pou Christian , Nkulikiyimfura Dieudonné , Brodin Petter , Druid Henrik , Mold Jeff , Frisén Jonas
Published: June 2022

Prostate cancer is a heterogeneous disease with a need for new prognostic biomarkers. Human leukocyte antigen (HLA) genes are highly polymorphic genes central to antigen presentation to T‐cells. Two alleles, HLA‐A*02:01 and HLA‐A*24:02, have been associated with prognosis in patients diagnosed with de novo metastatic prostate cancer. We leveraged the next‐generation sequenced cohorts CPC‐GENE and TCGA‐PRAD to examine HLA alleles, antiviral T‐cell receptors and prostate cancer disease recurrence after prostatectomy. Carrying HLA‐A*02:01 (111/229; 48% of patients) was independently associated with disease recurrence in patients with low‐intermediate risk prostate cancer. HLA‐A*11 (carried by 42/441; 10% of patients) was independently associated with rapid disease recurrence in patients with high‐risk prostate cancer. Moreover, HLA‐A*02:01 carriers in which anti‐cytomegalovirus T‐cell receptors (CMV‐TCR) were identified in tumors (13/144; 10% of all patients in the cohort) had a higher risk of disease recurrence than CMV‐TCR‐negative patients. These findings suggest that HLA‐type and CMV immunity may be valuable biomarkers for prostate cancer progression.
Offline recommender system evaluation: Challenges and new directions
Authors: Castells Pablo , Moffat Alistair
Published: June 2022

Offline evaluation is an essential complement to online experiments in the selection, improvement, tuning, and deployment of recommender systems. Offline methodologies for recommender system evaluation evolved from experimental practice in Machine Learning (ML) and Information Retrieval (IR). However, evaluating recommendations involves particularities that pose challenges to the assumptions upon which the ML and IR methodologies were developed. We recap and reflect on the development and current status of recommender system evaluation, providing an updated perspective. With a focus on offline evaluation, we review the adaptation of IR principles, procedures and metrics, and the implications of those techniques when applied to recommender systems. At the same time, we identify the singularities of recommendation that require different responses, or involve specific new needs. In addition, we provide an overview of important choices in the configuration of experiments that require particular care and understanding; discuss broader perspectives of evaluation such as recommendation value beyond accuracy; and survey open challenges such as experimental biases, and the cyclic dimension of recommendation.
Sustainable and Bench‐Stable Photoactive Aqueous Nanoaggregates of Cu(II) for ppm Level Cu(I) Catalysis in Water
Authors: Sharma Sudripet , Parmar Saurav , Ibrahim Faisal , Clark Adam H. , Nachtegaal Maarten , Jasinski Jacek B. , Gallou Fabrice , Kozlowski Pawel M. , Handa Sachin
Published: June 2022

The nanomaterial containing amphiphile‐stabilized mononuclear Cu(II) is developed. The material is characterized by various spectroscopic techniques, such as X‐ray absorption spectrscopy (XAS), high‐resolution transmission electron microscopy, nuclear magnetic resonance (NMR), UV‐vis, and infrared spectroscopies. Since the structural data for the amphiphile‐bound Cu(II) center is not available, a theoretical model based on DFT calculations is employed. The analyses based on NMR spectroscopic data, including the isotope labeling, support that the tertiary amide group of the amphiphile binds to the Cu surface. Likewise, the bond distances found by XAS spectroscopy agree with the theoretical model. Time‐dependent DFT studies predict that the low‐lying excited state has a dominant ligand‐to‐metal charge transfer (LMCT) character. Cu(II) changes to Cu(I) assisted by the LMCT excitation upon visible light irradiation, generating robust catalytically active species. The catalytic activity for domino azidation‐[3+2] cycloaddition reactions in water is investigated. The catalytic protocol is applicable on various substrates, and the catalytic material is stable under ambient conditions for up to three months.
Nonvolatile Control of Metal–Insulator Transition in VO2 by Ferroelectric Gating
Authors: Lee Yoon Jung , Hong Kootak , Na Kyeongho , Yang Jiwoong , Lee Tae Hyung , Kim Byungsoo , Bark Chung Wung , Kim Jae Young , Park Sung Hyuk , Lee Sanghan , Jang Ho Won
Published: June 2022

Controlling phase transitions in correlated materials yields emergent functional properties, providing new aspects to future electronics and a fundamental understanding of condensed matter systems. With vanadium dioxide (VO2), a representative correlated material, an approach to control a metal–insulator transition (MIT) behavior is developed by employing a heteroepitaxial structure with a ferroelectric BiFeO3 (BFO) layer to modulate the interaction of correlated electrons. Owing to the defect‐alleviated interfaces, the enhanced coupling between the correlated electrons and ferroelectric polarization is successfully demonstrated by showing a nonvolatile control of MIT of VO2 at room temperature. The ferroelectrically‐tunable MIT can be realized through the Mott transistor (VO2/BFO/SrRuO3) with a remanent polarization of 80 µC cm−2, leading to a nonvolatile MIT behavior through the reversible electrical conductance with a large on/off ratio (≈102), long retention time (≈104 s), and high endurance (≈103 cycles). Furthermore, the structural phase transition of VO2 is corroborated by ferroelectric polarization through in situ Raman mapping analysis. This study provides novel design principles for heteroepitaxial correlated materials and innovative insight to modulate multifunctional properties.
A Potent Micron Neoantigen Tumor Vaccine GP‐Neoantigen Induces Robust Antitumor Activity in Multiple Tumor Models
Authors: Jing Zhe , Wang Shuqing , Xu Keyuan , Tang Qian , Li Wenjing , Zheng Wei , Shi Haobo , Su Kailing , Liu Yanting , Hong Zhangyong
Published: June 2022

Therapeutic tumor neoantigen vaccines have been widely studied given their good safety profile and ability to avoid central thymic tolerance. However, targeting antigen‐presenting cells (APCs) and inducing robust neoantigen‐specific cellular immunity remain challenges. Here, a safe and broad‐spectrum neoantigen vaccine delivery system is proposed (GP‐Neoantigen) based on β‐1,3‐glucan particles (GPs) derived from Saccharomyces cerevisiae and coupling peptide antigens with GPs through convenient click chemistry. The prepared system has a highly uniform particle size and high APC targeting specificity. In mice, the vaccine system induced a robust specific CD8+ T cell immune response and humoral immune response against various conjugated peptide antigens and showed strong tumor growth inhibitory activity in EG7·OVA lymphoma, B16F10 melanoma, 4T1 breast cancer, and CT26 colon cancer models. The combination of the toll‐like receptors (TLRs) agonist PolyI:C and CpG 2395 further enhanced the antitumor response of the particle system, achieving complete tumor clearance in multiple mouse models and inducing long‐term rejection of reinoculated tumors. These results provide the broad possibility for its further clinical promotion and personalized vaccine treatment.
Transparent Conducting Films Based on Carbon Nanotubes: Rational Design toward the Theoretical Limit
Authors: Ilatovskii Daniil A. , Gilshtein Evgeniia P. , Glukhova Olga E. , Nasibulin Albert G.
Published: June 2022

Electrically conductive thin‐film materials possessing high transparency are essential components for many optoelectronic devices. The advancement in the transparent conductor applications requires a replacement of indium tin oxide (ITO), one of the key materials in electronics. ITO and other transparent conductive metal oxides have several drawbacks, including poor flexibility, high refractive index and haze, limited chemical stability, and depleted raw material supply. Single‐walled carbon nanotubes (SWCNTs) are a promising alternative for transparent conducting films (TCFs) because of their unique and excellent chemical and physical properties. Here, the latest achievements in the optoelectronic performance of TCFs based on SWCNTs are analyzed. Various approaches to evaluate the performance of transparent electrodes are briefly reviewed. A roadmap for further research and development of the transparent conductors using “rational design,” which breaks the deadlock for obtaining the TCFs with a performance close to the theoretical limit, is also described.
Flood tolerance and flood loss predictions for tepary bean across the U.S. Southern Great Plains
Authors: Witt Travis W. , Flynn K. Colton , Villavicencio Cindy , Northup Brian K.
Published: June 2022

Flooding can cause billions of dollars in crop losses per year. One method to combat susceptibility to flooding is through the identification and use of crops that withstand short flooding events. Tepary bean (Phaseolus acutifolius A. Gray) is an underused crop native to North America and currently grown in small amounts by the indigenous peoples of the Sonoran Desert of northern Mexico and southwestern United States. The genome of tepary bean is being used to improve heat, drought, and pest tolerances in common bean (Phaseolus vulgaris L.) through morpho‐physiological changes to the shoots and roots. This study evaluated the effect of different flooding periods on biomass production and tissue C and N content of tepary bean compared with soybean [Glycine max (L.) Merr.]. The study also defined areas of Kansas and Oklahoma that may flood during periods of 1–3 d and potential effects on the two legumes. The analysis determined that for any 1 yr, 22% of Kansas cropland would flood during a 24‐h period and 16% would flood during a 72‐h (3‐d) period. For Oklahoma, 30% of cropland would flood during a 24‐h period and 25% would flood during a 72‐h period. Although tepary bean withstands the abiotic stresses of high temperature and low precipitation, there was less evidence of flood tolerance. Overall, tepary bean genotypes survive 24‐h flooding events, whereas 72‐h events are detrimental to all traits evaluated. The highly erratic high intensity summer rainfalls common to the Southern Great Plains may reduce the ability of tepary bean to dependably produce biomass. Future breeding efforts should include developing flood tolerance in tepary bean to expand the region of use for this legume.
Magnetically accelerated thermal energy storage within Fe3O4‐anchored MXene‐based phase change materials
Authors: Gao Yan , Tang Zhaodi , Chen Xiao , Yan Jiamin , Jiang Yu , Xu Jianhang , Tao Zhang , Wang Lei , Liu Zhimeng , Wang Ge
Published: June 2022

Inherent weak photon‐capturing ability is a long‐standing bottleneck for pristine phase change materials (PCMs) in photothermal conversion application. To conquer this difficulty, herein, magnetic Fe3O4 nanoparticles were in situ anchored between the layers and the surface of two‐dimensional MXene for the infiltration of myristic acid (MA) by an in situ chemical anchoring strategy. Benefiting from the synergistic localized surface plasmon resonance effect of MXene and Fe3O4 nanoparticles, our designed MXene@Fe3O4‐MA composite PCMs harvested an ultrahigh photothermal conversion efficiency of 97.7%. During the photothermal conversion process, MXene can capture photons and convert solar energy into heat energy efficiently, and the in situ anchored Fe3O4 nanoparticles further enhanced the photothermal conversion efficiency. Moreover, the introduction of Fe3O4 nanoparticles improved the thermal energy storage density (144.17 J/g) of MXene‐MA composite PCMs since Fe3O4 nanoparticles provided more heterogeneous nucleation sites for MA. Simultaneously, MXene@Fe3O4‐MA composite PCMs were endowed with excellent paramagnetism, and realized efficient magnetic‐thermal conversion. Additionally, MXene@Fe3O4‐MA composite PCMs exhibited excellent energy conversion stability, thermal stability, and reliability after undergoing multiple thermal cycles. Therefore, high‐performance MXene@Fe3O4‐based energy conversion composite PCMs are promising candidates to accelerate efficient utilization of the practical solar energy and magnetic energy
Changes in renal function in patients with chronic hepatitis C treated with sofosbuvir‐velpatasvir
Authors: Su Pei‐Kai , Chang Te‐Sheng , Tung Shui‐Yi , Wei Kuo‐Liang , Shen Chien‐Heng , Hsieh Yung‐Yu , Chen Wei‐Ming , Chen Yi‐Hsing , Chen Chun‐Hsien , Yen Chih‐Wei , Xu Huang‐Wei , Tung Wei‐Ling , Chang Kao‐Chi
Published: June 2022

Direct‐acting antivirals (DAAs) have become an effective first‐line treatment for chronic hepatitis C (CHC), and the fixed‐dose combination of sofosbuvir (SOF) and velpatasvir (VEL) is one of the most important pangenotypic DAA regimen according to present treatment guideline. The association between SOF‐based regimens and renal toxicity remains controversial. A total of 953 patients including 130 with estimated glomerular filtration rate (eGFR) ≤ 60 mL/min/1.73m2 and 823 with eGFR > 60 mL/min/1.73m2 receiving SOF/VEL therapy for 12 weeks were enrolled in this study. The eGFR was assessed at baseline, end of treatment (EOT), and 12 weeks after completion of the therapy (end of follow‐up, EOF). The eGFR in patients with eGFR ≤ 60 mL/min/1.73m2 increased from baseline (47.89 ± 10.25 mL/min/1.73m2) to EOT (51.65 ± 15.92; P < .001) and EOF (51.51 ± 14.46 mL/min/1.73m2; P < .05). The eGFR in patients with eGFR > 60 mL/min/1.73m2 at baseline (91.52 ± 22.06 mL/min/1.73m2) was lower at EOT (90.37 ± 22.3; P < .05), with no difference between EOT and EOF (P = .06). Multivariable analysis showed that a higher serum albumin level was associated with a lower risk of eGFR decrease at EOT, and the patients with baseline eGFR > 60 mL/min/1.73m2 were associated with a higher risk of eGFR decrease at EOF. The rates of sustained virologic response 12 weeks after treatment cessation (SVR12) were 99.2% in per‐protocol analysis, and the most common adverse events were fatigue (4.7%), abdominal discomfort (4.5%), and skin itching (3.7%). In conclusion, renal function improved after the SOF/VEL treatment in patients with CHC and chronic kidney disease. Thus, SOF/VEL was safe, effective, and tolerable in these patients.
Clinical characteristics, prognostic indicators, and survival outcomes in intravascular lymphoma: Mayo Clinic experience (2003–2018)
Authors: Seegobin Karan , Li Zhuo , Alhaj Moustafa Muhamad , Majeed Umair , Wang Jing , Jiang Liuyan , Kuhlman Justin , Menke David , Li Ke , Kharfan‐Dabaja Mohamed A. , Ayala Ernesto , Iqbal Madiha , Nowakowski Grzegorz S. , Habermann Thomas M. , Witzig Thomas E. , Johnston Patrick , Thompson Carrie , Ansell Stephen , Tun Han W.
Published: June 2022

Intravascular lymphoma (IVL) is a rare extranodal non‐Hodgkin lymphoma. We performed a retrospective analysis of 55 IVL patients who were treated at our institution 2003–2018. Median age at diagnosis was 68 years, and 64% were males. The most frequent presenting symptoms were skin rash 43% and weight loss 30%. MRI brain on IVL patients with CNS involvement (CNS‐IVL) showed multifocal involvement in 76% (13/17). 89% (17/19) of non‐CNS‐IVL patients with abnormal FDG‐PET had biopsy of an avid lesion resulting in definitive diagnosis. The top diagnostic biopsy site was the bone marrow (45%). 56% had multiorgan involvement. Based on CNS involvement, 36.5% (20/55) had CNS‐IVL and 63.5% (35/55) had non‐CNS‐IVL. CNS‐IVL group consists of clinically isolated CNS involvement (CNS‐only IVL) (22%;12/55) and mixed clinical CNS and peripheral site involvement (M‐IVL) (14.5%; 8/55). Non‐CNS‐IVL group consists of clinically isolated skin involvement (skin‐only IVL) (9%; 5/55) and peripheral IVL with or without skin involvement (P‐IVL); (54.5%; 30/55). Skin involvement was predominantly in the lower extremities. Pathologically, 89% (48/54) were B‐cell IVL. Rituximab + high‐dose methotrexate‐based regimen were used in 75% (12/16) of CNS‐IVL patients and RCHOP in 60% (17/28) of non‐CNS‐IVL patients. Estimated 5‐year progression free survival (PFS) and overall survival (OS) for the entire cohort were 38.6% and 52%, respectively. Skin‐only IVL was associated with excellent survival. Platelet count <150x109/L, age > 60Y, and treatment without Rituximab were poor prognostic factors. Further research is necessary to identify novel therapies.
An integral monitoring concept for data‐driven detection and localization of incipient leakages by fusion of process and environment data
Authors: Kasten Kristian , Zhu Caroline Charlotte , Birk Joachim , Ding Steven X.
Published: June 2022

The risk of leakages in process industry is environmentally critical and potentially hazardous. Many technologies and schemes for process monitoring are theoretically developed and applied in an industrial context. Nevertheless, most approaches still focus on individual monitoring of a process and its environment. The major challenge is the lack of a priori knowledge about the leakage. This paper introduces a new approach combining monitoring of the environment and its embedded process. The application on an industrial use‐case in a real plant environment illustrates the success of this combined monitoring approach as well as a decision support to localize an incipient leakage.
A New AdvancedMRIBiomarker for Remyelinated Lesions in Multiple Sclerosis
Authors: Rahmanzadeh Reza , Galbusera Riccardo , Lu Po‐Jui , Bahn Erik , Weigel Matthias , Barakovic Muhamed , Franz Jonas , Nguyen Thanh D. , Spincemaille Pascal , Schiavi Simona , Daducci Alessandro , La Rosa Francesco , Absinta Martina , Sati Pascal , Bach Cuadra Meritxell , Radue Ernst‐Wilhelm , Leppert David , Kuhle Jens , Kappos Ludwig , Brück Wolfgang , Reich Daniel S. , Stadelmann Christine , Wang Yi , Granziera Cristina
Published: June 2022

Objectives

Neuropathological studies have shown that multiple sclerosis (MS) lesions are heterogeneous in terms of myelin/axon damage and repair as well as iron content. However, it remains a challenge to identify specific chronic lesion types, especially remyelinated lesions, in vivo in patients with MS.

Methods

We performed 3 studies: (1) a cross‐sectional study in a prospective cohort of 115 patients with MS and 76 healthy controls, who underwent 3 T magnetic resonance imaging (MRI) for quantitative susceptibility mapping (QSM), myelin water fraction (MWF), and neurite density index (NDI) maps. White matter (WM) lesions in QSM were classified into 5 QSM lesion types (iso‐intense, hypo‐intense, hyperintense, lesions with hypo‐intense rims, and lesions with paramagnetic rim legions [PRLs]); (2) a longitudinal study of 40 patients with MS to study the evolution of lesions over 2 years; (3) a postmortem histopathology‐QSM validation study in 3 brains of patients with MS to assess the accuracy of QSM classification to identify neuropathological lesion types in 63 WM lesions.

Results

At baseline, hypo‐ and isointense lesions showed higher mean MWF and NDI values compared to other QSM lesion types (p < 0.0001). Further, at 2‐year follow‐up, hypo‐/iso‐intense lesions showed an increase in MWF. Postmortem analyses revealed that QSM highly accurately identifies (1) fully remyelinated areas as hypo‐/iso‐intense (sensitivity = 88.89% and specificity = 100%), (2) chronic inactive lesions as hyperintense (sensitivity = 71.43% and specificity = 92.00%), and (3) chronic active/smoldering lesions as PRLs (sensitivity = 92.86% and specificity = 86.36%).

Interpretation

These results provide the first evidence that it is possible to distinguish chronic MS lesions in a clinical setting, hereby supporting with new biomarkers to develop and assess remyelinating treatments. ANN NEUROL 2022;92:486–502
Designing Protein‐Based Probes for Sensing Biological Analytes with Magnetic Resonance Imaging
Authors: Yun Jason , Baldini Michelle , Chowdhury Rochishnu , Mukherjee Arnab
Published: June 2022

Genetically encoded sensors provide unique advantages for monitoring biological analytes with molecular and cellular‐level specificity. While sensors derived from fluorescent proteins represent staple tools in biological imaging, these probes are limited to optically accessible preparations owing to physical curbs on light penetration. In contrast to optical methods, magnetic resonance imaging (MRI) may be used to noninvasively look inside intact organisms at any arbitrary depth and over large fields of view. These capabilities have spurred the development of innovative methods to connect MRI readouts with biological targets using protein‐based probes that are in principle genetically encodable. Here, we highlight the state‐of‐the‐art in MRI‐based biomolecular sensors, focusing on their physical mechanisms, quantitative characteristics, and biological applications. We also describe how innovations in reporter gene technology are creating new opportunities to engineer MRI sensors that are sensitive to dilute biological targets.
A new hybrid ligand and its metal complexes from a natural plant (Styrax officinalis) bearing egonol, thiosemicarbazone and oxime units, and their anti‐cancer activities
Authors: Babahan‐Bircan Ilknur , Emirdağ Safiye , Özmen Ali , Abbak Mürüvvet , Ujam Oguejiofo T. , Demirkaya Ilke , Günay M. Emin
Published: June 2022

A novel hybrid ligand, a vic‐dioxime ligand (ETO), containing thiosemicarbazone and egonol moieties from a natural plant (Styrax officinalis) and its trinuclear [Ni(II), Cu(II), Co(II), and Fe(II)] and mononuclear [Pd(II) and Zn(II)] complexes have been synthesized and characterized. The ligand, complexes, and natural components were characterized by conventional spectroscopic techniques (IR, NMR, and MS) and evaluated against two human cancer cell lines (MCF‐7 and PC‐3) to determine their antiproliferative and apoptotic properties. Apoptotic or necrotic effects were detected in both cancer cell lines using the Hoechst/propidium iodide double‐staining method. Paclitaxel was used as a positive control (1 μM). The results displayed that the compounds obtained in this study were effective in the concentration range of 5–40 μM in prostate and breast cancer cell lines. It can be said that the compounds (egonol, its derivatives, hybrid ligand, and its metal complexes) are mostly more effective in PC‐3 migration lines. Consequently, the cytotoxic efficiencies of [Cu3(ETO)2·4Cl], 5.27 μM for MCF‐7 and 13.44 μM for PC‐3 and [Zn (ETO)·2Cl] 11.73 μM for MCF‐7 and 9.32 μM for PC‐3 were observed to be close to paclitaxel (a drug used as a cancer chemotherapeutic agent). [Cu3(ETO)2·4Cl] were more effective on the MCF‐7 cell line. Besides this result, [Zn (ETO)·2Cl] was more effective on the PC‐3 cell lines and was more effective by triggering apoptosis in the cells.
Mannose‐targeting Concanavalin A−Epirubicin Conjugate for Targeted Intravesical Chemotherapy of Bladder Cancer
Authors: Huo Fan , Zhang Yang , Li Yiran , Bu Huagang , Zhang Yaliang , Li Wei , Guo Yuna , Wang Lan , Jia Ru , Huang Tengfei , Zhang Weiyi , Li Pengchao , Ding Lin , Yan Chao
Published: June 2022

Intravesical instillation of chemotherapeutic drugs such as epirubicin (EPI) is routinely used to prevent tumor recurrence and progression after transurethral resection of bladder tumor. However, the lack of tumor selectivity often causes severe damage to normal bladder urothelium leading to intolerable side effects. Here, we analyzed abnormal changes in glycosylation in bladder cancer and identified mannose as the most aberrantly expressed glycan on the surface of bladder cancer cell lines and human bladder tumor tissues. We then constructed a lectin‐drug conjugate by linking concanavalin A (ConA) – a lectin that specifically binds to mannose, with EPI through a pH‐sensitive linker. This ConA−EPI conjugate conferred EPI with mannose‐targeting ability and selectively internalized cancer cells in vitro. This conjugate showed selective cytotoxicity to cancer cells in vitro and better antitumor activity in an orthotopic mouse model of bladder cancer. Our lectin‐drug conjugation strategy makes targeted intravesical chemotherapy of bladder cancer possible.
Membrane Disruptive Action of Cationic Antibacterial Peptide B1CTcu3
Authors: Ajayakumar Neethu , Narayanan Pratibha , Anitha Anju Krishnan , Mahendran Kozhinjampara R. , Kumar Kesavakurup Santhosh
Published: June 2022

A twenty‐two‐residue peptide Brevinin1 Clinotarsus curtipus‐3 (B1CTcu3), identified from the skin secretion of frog Clinotarsus curtipes of the Western Ghats, exhibited a broad range of antibacterial activity against Gram‐negative and Gram‐positive bacteria, including the methicillin‐resistant Staphylococcus aureus (MRSA). It showed anti‐biofilm activity even at sub‐minimum inhibitory concentration (sub‐MIC) against Pseudomonas aeruginosa and Staphylococcus aureus. Analysis of the scanning electron microscopic (SEM) images, confocal images, flow cytometric data and the effect of salt concentration on antibacterial potency suggests that the killing action of the peptide is through the membranolytic process. Single channel electric recording confirmed that the peptide elicited pores on the bacterial cell membrane as it induces a heterogeneous channel in the lipid bilayer. It also showed cytotoxicity against MDA‐MB‐231 breast cancer cell with IC50 of 25 μM. B1CTcu3 peptide could serve as the template for next‐generation antibacterial agents, particularly against antibiotic resistant pathogenic bacteria.
Ru‐P Nanoalloy from Elemental Phosphorus as P‐Source: Synthesis, Characterization and Catalytic Evaluation
Authors: Vanni Matteo , Provinciali Giacomo , Calvo Fuencisla Delgado , Carignani Elisa , Dreyfuss Sébastien , Mézailles Nicolas , Mio Antonio Massimiliano , Nicotra Giuseppe , Caporali Stefano , Borsacchi Silvia , Peruzzini Maurizio , Caporali Maria
Published: June 2022

Binary ruthenium‐phosphorus nanoparticles (NPs) with different Ru/P ratio were prepared in mild conditions using white phosphorus (P4) as phosphorus source. Accurate study of both their morphology and structure at the atomic level by TEM and HAADF‐STEM, respectively, showed that Ru2P and RuP have a narrow size distribution (ca. 3.3 nm) and are lacking an ordered ruthenium phosphide lattice.31P Solid State NMR highlighted the existence of three different phosphorus species consistently with the lack of a metal phosphide lattice and finally XPS revealed that the true nature of these nanoparticles can be better described as a ruthenium‐phosphorus alloy. As a benchmark test, the selective hydrogenation of nitroarenes to primary aromatic amines was studied and evidenced how the P‐alloying imparts a surface modification resulting in a higher catalytic activity and excellent chemoselectivity of Ru2P in comparison to Ru(0) and RuP.
Chemical engineering at crossroads
Authors: Nandakumar Krishnaswamy , Tyagi Mayank , Xu Ye , Valsaraj Kalliat T. , Joshi Jyeshtharaj B.
Published: June 2022

Through periodic introspection and assessment, the chemical engineering field has developed a mature undergraduate curriculum built on a strong science background in mathematics, physics, and chemistry. This brings a unique set of skills in transport, reaction engineering, and thermodynamics, coupled with suitable process systems engineering and process design courses, to supply well‐trained engineers to a vast array of process manufacturing facilities. These facilities produce basic chemicals, pharmaceuticals, oil and gas, petrochemicals, food and agricultural products, minerals, and materials. While this maturity has served existing industries well, we argue that the chemical engineering field is at crossroads between managing the curriculum of undergraduate and graduate education to supply the needs of established industries while creating innovators for emerging industries. While this is a great opportunity for yet another introspection, we caution that the inadvertent cannibalization of the field must be avoided. We do argue in favour of adding a biology sequence and a computational science sequence to the core at the undergraduate level in a related perspective article.
N‐Substituted Carbazole Derivate Salts as Stable Organic Electrodes for Anion Insertion
Authors: Russo Roberto , Murugesan Rajesh , Jamali Arash , Chotard Jean‐Noël , Toussaint Gwenaelle , Frayret Christine , Stevens Philippe , Becuwe Matthieu
Published: June 2022

Herein the design, synthesis and electrochemical characterization of a set of insoluble molecular carbazole derivatives for electrochemical energy storage is proposed. Two strategies, based on the incorporation of an insoluble fragment or dimerization, were carried out to avoid the dissolution of the active material in the organic carbonate‐based liquid electrolyte solvent. The synthesized compounds enable the reversible anion intercalation from electrolyte, around 4.0 V vs. Li, through a p‐type mechanism, and showed an improvement in cycling stability, making them suitable for application as metal‐free positive electrodes for electrochemical energy storage systems. A first investigation to determine the impact of the electrolyte composition on the anion insertion mechanism and complemented with understanding of the redox mechanism was also carried out.