bluuebunny/crossref_metadata_2025 huggingface dataset:
Melt Viscosity of Random Copolymers of Butadiene and Styrene Prepared by Anionic Polymerization
Authors: Kraus Gerard , Gruver J. T.
Published: July 2002

The melt viscosity of narrow distribution, linear, random copolymers of butadiene (75%) and styrene (25%) prepared by anionic polymerization was investigated in both the Newtonian and non-Newtonian regimes of flow. The Newtonian viscosity is shown to obey the usual 3.4th power dependence on Mw The temperature dependence is represented satisfactorily by the Vogel equation, as modified by Berry and Fox. Non-Newtonian viscosities are reduced to a single master curve for all polymers, temperatures, and shear rates, using the Newtonian viscosity as the sole shift factor (η/η0 vs. η0γ̇). Comparison of this master curve with those of two narrow distribution polybutadienes of different microstructure produces agreement within 0.2 of a logarithmic unit on the η0γ̇-scale. All three master curves lie one to two decades toward higher reduced shear rates than various “universal” curves reported in the literature for polymers of broader molecular weight distribution.
Volume Changes Accompanying the Extension of Rubber
Authors: Penn Robert W.
Published: July 2002

The volume changes accompanying extension of peroxide vulcanizates of natural gum rubber were measured using a dilatometer technique. Measurements of the force-extension behavior and compressibilities were made on the same samples for the range of extension and volume change covered in the volume experiments. A constant compressibility was found; however, the volume changes accompanying extension were not proportional to the isotropic part of the stress. Thus, the strain energy cannot be separated into a sum of two parts, one due to the shear and one due to the dilatation.
On the Rheology of Dilute Suspensions of Rigid Particles
Authors: Kaloni P. N. , Desilva C. N.
Published: July 2002

The theory of oriented fluids is applied to discuss the behavior of dilute suspensions of rigid particles. The behavior of particles in some simple flows, e.g., rectangular hyperbolic flow, hyperbolic radial flow and Couette flow, is analyzed. Expressions for the stress components for dilute suspensions of these flows are also given.
Transient rheological response and morphology evolution of immiscible polymer blends
Authors: Vinckier I. , Moldenaers P. , Mewis J.
Published: July 2002

The response of semi-concentrated model blends (10% disperse phase), consisting of slightly viscoelastic polymers, on a stepwise increase in shear rate is investigated. During the initial stage of the response droplets deform into fibrils. The shear and normal stress transients during the deformation process are modeled by combining the approach of Doi and Ohta with the affine deformation theory for single droplet behaviour. In the proposed equations the scaling relations of Doi and Ohta for transient stresses are preserved. They do not contain any fitting parameter. First, the model predictions are compared with experimental results on model blends. Good agreement is found under conditions for which affine deformation is expected. Second the applicability of the scaling relations of the Doi–Ohta theory is verified experimentally. Although the scaling laws should only apply for 50:50 mixtures of Newtonian liquids with equal viscosity, the experiments show that they hold as well for semiconcentrated systems containing slightly viscoelastic components with viscosity ratios deviating from unity.
Carbon Nanotube@Nickel Hydroxide Nanosheets Core–Shell Nanostructures Enabling Thermally Assisted 3D‐Printed Solid‐State Microsupercapacitors
Authors: Yu Wei , Yin Xiangkai , Wang Jiuhong , Ding Shujiang
Published: November 2022

Microsupercapacitors have picked up a remarkable reputation as prospective micropower sources for compact electronics. Unfortunately, the fabricating complexity of electrode structures and preparing sophistication of electrode materials have prevented their practical deployment. Herein, a one‐step low‐temperature precipitation method is applied to straightforwardly self‐assemble porous Ni(OH)2 nanosheets on the surface of carbon nanotubes (CNTs) surface beneath electrostatic interaction. The developed core–shell 1D CNTs@Ni(OH)2 nanosheets nanostructures exhibit high electron and ion conductivity, a sign of excellent energy storage capability. In this vein, a thermally assisted 3D printing process is intelligently regulated to enable the fabrication of 3D interdigital electrodes from as‐obtained materials. The ultimate solid‐state microsupercapacitors of CNTs@Ni(OH)2 nanosheets core–shell nanostructures in this way exhibit excellent cycle stability and offer an exceptional areal capacitance of 39.6 mF cm−2, approximately a size of or two higher than that of C‐based partners. A strong foundation for high‐quality microsupercapacitors is laid by the high specific capacity of CNTs@Ni(OH)2 nanosheets core–shell nanostructures and the ability to fabricate 3D interdigital electrodes using a thermally assisted 3D printing process.
Checkpoint Nano‐PROTACs for Activatable Cancer Photo‐Immunotherapy
Authors: Zhang Chi , Xu Mengke , He Shasha , Huang Jingsheng , Xu Cheng , Pu Kanyi
Published: November 2022

Checkpoint immunotherapy holds great potential to treat malignancies via blocking the immunosuppressive signaling pathways, which however suffers from inefficiency and off‐target adverse effects. Herein, checkpoint nano‐proteolysis targeting chimeras (nano‐PROTACs) in combination with photodynamic tumor regression and immunosuppressive protein degradation to block checkpoint signaling pathways for activatable cancer photo‐immunotherapy are reported. These nano‐PROTACs are composed of a photosensitizer (protoporphyrin IX, PpIX) and an Src homology 2 domain‐containing phosphatase 2 (SHP2)‐targeting PROTAC peptide (aPRO) via a caspase 3‐cleavable segment. aPRO is activated by the increased expression of caspase 3 in tumor cells after phototherapeutic treatment and induces targeted degradation of SHP2 via the ubiquitin‐proteasome system. The persistent depletion of SHP2 blocks the immunosuppressive checkpoint signaling pathways (CD47/SIRPα and PD‐1/PD‐L1), thus reinvigorating antitumor macrophages and T cells. Such a checkpoint PROTAC strategy synergizes immunogenic phototherapy to boost antitumor immune response. Thus, this study represents a generalized PROTAC platform to modulate immune‐related signaling pathways for improved anticancer therapy.
Microenvironment‐Based Diabetic Foot Ulcer Nanomedicine
Authors: Huang Fang , Lu Xiangyu , Yang Yan , Yang Yushan , Li Yongyong , Kuai Le , Li Bin , Dong Haiqing , Shi Jianlin
Published: November 2022

Diabetic foot ulcers (DFU), one of the most serious complications of diabetes, are essentially chronic, nonhealing wounds caused by diabetic neuropathy, vascular disease, and bacterial infection. Given its pathogenesis, the DFU microenvironment is rather complicated and characterized by hyperglycemia, ischemia, hypoxia, hyperinflammation, and persistent infection. However, the current clinical therapies for DFU are dissatisfactory, which drives researchers to turn attention to advanced nanotechnology to address DFU therapeutic bottlenecks. In the last decade, a large number of multifunctional nanosystems based on the microenvironment of DFU have been developed with positive effects in DFU therapy, forming a novel concept of “DFU nanomedicine”. However, a systematic overview of DFU nanomedicine is still unavailable in the literature. This review summarizes the microenvironmental characteristics of DFU, presents the main progress of wound healing, and summaries the state‐of‐the‐art therapeutic strategies for DFU. Furthermore, the main challenges and future perspectives in this field are discussed and prospected, aiming to fuel and foster the development of DFU nanomedicines successfully.
Substituent‐controlled aggregate luminescence: Computational unraveling of S1/S0 surface crossing
Authors: Yin Ping‐An , Ou Qi , Peng Qian , Shuai Zhigang
Published: November 2022

We computationally investigated the molecular aggregation effects on the excited state deactivation processes by considering both the direct vibrational relaxation and the S0/S1 surface crossing, that is, the minimum energy conical intersection (MECI). Taking classical AIEgens bis(piperidyl)anthracenes (BPAs) isomers and the substituted silole derivatives as examples, we show that the deformation of MECI always occurs at the atom with greater hole/electron overlap. Besides, the energetic and structural changes of MECI caused by substituent has been investigated. We find that effective substituent such as the addition of the electron‐donating groups, which can polarize the distribution of hole/electron density of molecules, will lead to the pyramidalization deformation of MECI occurring at the substituent position and simultaneously reduce the required energy to reach MECI. And MECI is sterically restricted by the surrounding molecules in solid phase, which remarkably hinders the non‐radiative decay through surface crossing. Through quantitative computational assessments of the fluorescence quantum efficiency for both solution and solid phases, we elucidate the role of MECI and its dependence on the substitutions through pyramidalization deformation, which give rise to the aggregation‐induced emission (AIE) phenomenon for 9,10‐BPA, to aggregation‐enhance emission (AEE) behavior for 1,4‐BPA, and to conventional aggregation‐caused quenching (ACQ) for 1,5‐BPA. We further verify such mechanism for siloles, for which we found that the substitutions do not change the AIE behavior. Our findings render a general molecular design approach to manipulating the aggregation effect for optical emission.
Alkaline‐Earth Metal Mediated Benzene‐to‐Biphenyl Coupling
Authors: Mai Jonathan , Morasch Michael , Jędrzkiewicz Dawid , Langer Jens , Rösch Bastian , Harder Sjoerd
Published: November 2022

Complex [(DIPePBDI)Ca]2(C6H6), with a C6H62−dianion bridging two Ca2+ions, reacts with benzene to yield [(DIPePBDI)Ca]2(biphenyl) with a bridging biphenyl2−dianion (DIPePBDI=HC[C(Me)N‐DIPeP]2; DIPeP=2,6‐CH(Et)2‐phenyl). The biphenyl complex was also prepared by reacting [(DIPePBDI)Ca]2(C6H6) with biphenyl or by reduction of [(DIPePBDI)CaI]2with KC8in presence of biphenyl. Benzene‐benzene coupling was also observed when the deep purple product of ball‐milling [(DIPPBDI)CaI(THF)]2with K/KI was extracted with benzene (DIPP=2,6‐CH(Me)2‐phenyl) giving crystalline [(DIPPBDI)Ca(THF)]2(biphenyl) (52 % yield). Reduction of [(DIPePBDI)SrI]2with KC8gave highly labile [(DIPePBDI)Sr]2(C6H6) as a black powder (61 % yield) which reacts rapidly and selectively with benzene to [(DIPePBDI)Sr]2(biphenyl). DFT calculations show that the most likely route for biphenyl formation is a pathway in which the C6H62−dianion attacks neutral benzene. This is facilitated by metal‐benzene coordination.
Strong Coupling of Chiral Frenkel Exciton for Intense, Bisignate Circularly Polarized Luminescence
Authors: Li Minghao , Nizar Shahana , Saha Sudipta , Thomas Anoop , Azzini Stefano , Ebbesen Thomas W. , Genet Cyriaque
Published: November 2022

We show that chiral Frenkel excitons yield intense circularly polarized luminescence with an intrinsic dissymmetry factor in emission glum as high as 0.08. This outstanding value is measured through thin films of cyanine J‐aggregates that form twisted bundles. Our measurements, obtained by a Mueller polarization analysis, are artifact‐free and reveal a quasi‐perfect correlation between the dissymmetry factors in absorption, gabs, and in emission glum. We interpret the bisignate dissymmetry factors as the signature of a strong coupling between chiral Frenkel excitons longitudinally excited along the bundles. We further resolve by polarimetry analysis the split in energy between the excited states with a Davydov splitting as small as 28 meV. We finally show the anti‐Kasha nature of the chiral emission bands with opposite optical chirality. These mirror‐imaged emissive chiroptical features emerge from the structural rigidity of the bundles that preserves the ground‐ and excited‐state chirality.
Biosynthesis of Hybrid Neutral Lipids with Archaeal and Eukaryotic Characteristics in Engineered Saccharomyces cerevisiae
Authors: Zhang Jianzhi , Li Tuo , Hong Zhilai , Ma Chenfei , Fang Xiaoting , Zheng Fengfeng , Teng Wenkai , Zhang Chuanlun , Si Tong
Published: November 2022

Discovery of the Asgard superphylum of archaea provides new evidence supporting the two‐domain model of life: eukaryotes originated from an Asgard‐related archaeon that engulfed a bacterial endosymbiont. However, how eukaryotes acquired bacterial‐like membrane lipids with a sn‐glycerol‐3‐phosphate (G3P) backbone instead of the archaeal‐like sn‐glycerol‐1‐phosphate (G1P) backbone remains unknown. In this study, we reconstituted archaeal lipid production in Saccharomyces cerevisiae by expressing unsaturated archaeol‐synthesizing enzymes. Using Golden Gate cloning for pathway assembly, modular gene replacement was performed, revealing the potential biosynthesis of both G1P‐ and G3P‐based unsaturated archaeol by uncultured Asgard archaea. Unexpectedly, hybrid neutral lipids containing both archaeal isoprenoids and eukaryotic fatty acids were observed in recombinant S. cerevisiae. The ability of yeast and archaeal diacylglycerol acyltransferases to synthesize such hybrid lipids was demonstrated.
Cycling a Tether into Multiple Rings: Pt‐Bridged Macrocycles for Differentiated Guest Recognition, Pseudorotaxane Transformations, and Guest Capture and Release
Authors: Soto Miguel A. , Carta Veronica , Suzana Ingrid , Patrick Brian O. , Lelj Francesco , MacLachlan Mark J.
Published: November 2022

Macrocycle engineering is a key topic in supramolecular chemistry. When synthesizing a ring, one can obtain either complex mixtures of macrocycles of different sizes or a single ring if a template is utilized. Here, we unite these approaches along with post‐synthetic modifications to transform a single tether into multiple rings—up to five per tether. The macrocycles contain two bridged phenylpyridine ligands that are connected through a Pt atom, which defines the rings’ shape, size, and host activity. All rings undergo redox reactions (between PtII and PtIV) that allow for large conformational changes. Their reactivity, together with their host performance, is a convenient way to control the capture and release of guests, to mediate ring transformations, and to control pseudorotaxane‐to‐pseudorotaxane conversions. This novel approach could serve to assemble other libraries of small ring molecules, create cyclic polymers bridged by responsive‐at‐metal nodes, and produce processable mechanically interlocked molecules.
Enhanced ethanol pervaporative selectivity of polydimethylsiloxane membranes by incorporating with graphene oxide@silica core‐shell structure
Authors: Peng Ping , Lan Yongqiang , Xu Amei , Liu Mengyao
Published: November 2022

A graphene oxide@silica core‐shell structure (GO@silica) was prepared and embedded into the polydimethylsiloxane (PDMS) to fabricate mixed matrix membranes (MMMs). Meanwhile, (3,3,3‐trifluoropropyl)triethoxysilane (TFTS) was employed to improve the compatibility between PDMS and GO@silica and create a hydrophobic membrane surface for improving the ethanol pervaporative performance. The scanning electron microscope (SEM) result showed that the resultant PDMS/GO@silica MMMs were smooth and defect‐free. Meanwhile, the increase in hydrophobicity, swelling degree, and PV performance was achieved because of the incorporation of the modified GO@silica. The maximal separation factor of 11.43 coupled with a high permeation flux of 223 g·m−2·h−1was observed when separating a 10 wt. % ethanol/water mixture at 30°C. Moreover, the MMMs displayed a stable PV performance during a 168‐h continuous operation.
Joint Studies of Spin Frustration Induced by Doping Small ZnSe Nanoparticles with Fe Atoms
Authors: Gutsev Lavrenty G. , Bindra Jasleen K. , Strouse Geoffrey F. , Aldoshin Sergey M. , Gutsev Gennady L.
Published: November 2022

As a 1.8 nm ZnSe nanocrystal is progressively doped with 1%, 5%, and 10% Fe, it shows a progressive change in its magnetic properties from a superparamagnetic FM‐dominated exchange type to an onset of AFM exchange with evidence of spin frustration. Magnetization measurements allow to obtain exchange coupling constants that are compared to the results of a Broken‐Symmetry Density Functional Theory (BS‐DFT) model of a doped (ZnSe)34 cluster. DFT shows a capability to reproduce the experimental pattern of the increasing influence of AFM exchange as doping concentration increases. The material phase segregates at the edges where strained rhombic surface sites are the preferred doping sites of iron. Large concentrations of iron leads to the formation of Fe clusters and complex exchange patterns that result in spin frustration in some iron trimers but none in the others. The spin frustration of these complex systems by assuming mirror symmetry of the sites when fitting by using BS‐DFT formalism is classified and analyzed. While some individual J constants obtained have significant errors, the averaged exchange constants are generally in good agreement with our experimental data.
How Porosity Affects the Performance of Piezoelectric Energy Harvesters and Sensors
Authors: Hassanpour Amiri Morteza , Asadi Kamal
Published: November 2022

Porosity has been experimentally employed to enhance the power output of piezoelectric energy harvesters. However, porosity lowers the breakdown voltage of the piezoelectric layer and hampers the pre‐poling of the piezoelectric, which is needed to achieve enhanced performance. Furthermore, the effect of fractional porosity and pore size on the poling conditions and the enhanced power output of the comprising piezoelectric harvesters is not yet known. Here, through finite‐element method simulations, it is shown that the enhanced performance of the porous piezoelectric harvesters is independent of the size and distribution of the pores and only depends on the fractional porosity. Moreover, it is shown that the presence of pores yields the emergence of local stress hot spots that are mainly responsible for improved performance. Moreover, it is suggested that the breakdown issue of the porous piezoelectric layers can be mitigated by poling the structures in a vacuum using electric fields below the threshold field for electron field emission from the piezoelectric layer.
Optimal tracking performance of communication‐constrained systems under energy constraints
Authors: Zhang Yuyao , Zhan Xisheng , Wu Jie , Yan Huaicheng
Published: November 2022

This paper investigates the optimal tracking performance of systems by considering packet dropouts, additive white Gaussian noise(AWGN), and coding under energy constraints. The optimal tracking performance of communication‐constrained systems is obtained by spectral decomposition and partial factorization. The results show that the optimal tracking performance of the system is related to intrinsic properties such as non‐minimum phase zeros and unstable poles. What's more, encoding, data loss rate, and AWGN are also able to affect the performance of the system. Finally, the correctness of the results is verified by specific examples.
Audiovisual temporal binding window narrows with age in autistic individuals
Authors: Ainsworth Kirsty , Bertone Armando
Published: November 2022

Atypical sensory perception has been recognized in autistic individuals since its earliest descriptions and is now considered a key characteristic of autism. Although the integration of sensory information (multisensory integration; MSI) has been demonstrated to be altered in autism, less is known about how this perceptual process differs with age. This study aimed to assess the integration of audiovisual information across autistic children and adolescents. MSI was measured using a non‐social, simultaneity judgment task. Variation in temporal sensitivity was evaluated via Gaussian curve fitting procedures, allowing us to compare the width of temporal binding windows (TBWs), where wider TBWs indicate less sensitivity to temporal alignment. We compared TBWs in age and IQ matched groups of autistic (n = 32) and neurotypical (NT; n = 73) children and adolescents. The sensory profile of all participants was also measured. Across all ages assessed (i.e., 6 through 18 years), TBWs were negatively correlated with age in the autistic group. A significant correlation was not found in the NT group. When compared as a function of child (6–12 years) and adolescent (13–18 years) age groups, a significant interaction of group (autism vs NT) by age group was found, whereby TBWs became narrower with age in the autistic, but not neurotypical group. We also found a significant main effect of age and no significant main effect of group. Results suggest that TBW differences between autistic and neurotypical groups diminishes with increasing age, indicating an atypical developmental profile of MSI in autism which ameliorates across development.
Cancer‐testis gene STK31 is regulated by methylation and promotes the development of pancreatic cancer
Authors: Gao Hao , Cai Baobao , Lu Zipeng , Wang Guangfu , Gao Yong , Miao Yi , Jiang Kuirong , Zhang Kai
Published: November 2022

Backgroud

Pancreatic cancer (PC) is a highly invasive malignancy with extremely poor prognosis. STK31 has been identified as a cancer‐testis (CT) gene, but its function in PC has not been elucidated well.

Methods

The effect of STK31 on cell proliferation, migration and invasion was investigated by in vitro and in vivo experiments and total RNA sequencing and targeted bisulfite sequencing was applied to explore the potential regulatory mechanisms of STK31 in PC.

Results

By analysis of tissue samples and the clinicopathologic features, we found that STK31 was reactivated in PC and associated with poor prognosis. In addition, the vitro and vivo studies indicated that STK31 could promote PC progression by facilitating cell proliferation, migration and invasion, and the indication. Targeted Bisulfite Sequencing showed that STK31 was regulated by methylation. Furthermore, the results of total RNA sequencing suggested that STK31 was closely related to signal transduction, metabolism, and the immune system.

Conclusions

This study demonstrates that STK31, as a CT gene, can promote the development of PC and is regulated by methylation. STK31 could be considered as a potential therapeutic target for PC.
When quantity takes on a quality of its own: A retrospective exploration of the lived experience of cumulative harm
Authors: Bryce India , Beccaria Gavin , McIlveen Peter , Du Preez Jan
Published: November 2022

Cumulative harm refers to the effects of an accumulation of adverse experiences in a child's life. An understanding of cumulative harm and its integration into practice frameworks, legislation, policy and service delivery is hailed as an imperative of critical social concern and has been demanded by researchers, practitioners, commissioners and coroners. However, there is minimal research exploring the nature and defining qualities of cumulative harm and the implications for individuals in adulthood. The present study uses interpretive phenomenological analysis to explore the lived experiences of cumulative harm in a sample of helping professionals. The findings of this study contribute knowledge to the definitions and typologies of child abuse, neglect and adversity, and draw on empirical evidence to broaden the scope of what constitutes childhood maltreatment. Further, the findings catalyse a paradigm shift that positions accumulation as a distinct harm type and clarifies the qualities which embody cumulative harm: persistent dysfunction, dysregulation, disadvantage and disconnection.
Anticancer Effect of Chlorambucil Enhanced by Chiral Phthalidyl Promoiety
Authors: Zhang Long , Cheng Yisa , Liu Ying‐Guo , Chen Xingkuan , Liu Hongmei
Published: November 2022

Phthalidyl promoiety has been used in several drugs, but they were all marketed in racemic form. The pharmaceutical effects of each enantiomer have not been clearly demonstrated. In this project, an anticancer chemotherapy drug, chlorambucil, was modified as enantiopure phthalidyl prodrugs. The enantiomers, together with phthalidyl unit and their racemic mixture, were then subject to the in vivo bioactivity tests against B16F10 melanoma cells. It was found that proper chirality within the promoiety had noticeably better in vivo pharmacological effects than the parent drug, the enantiomer and racemic mixture. This merit perhaps could be extended from the phthalidyl prodrugs to other chirality containing prodrugs.
PROTOCOL: The effectiveness of psychosocial interventions for reducing problematic substance use, improving mental health, and improving housing stability for adults experiencing homelessness: A systematic review and meta‐analysis
Authors: O'Leary Chris , Teixeira Ligia , Coren Esther , Kiss Zsolt , Roberts Anton , Amitage Harry
Published: November 2022

This systematic review is part of a broader evidence synthesis which aims to produce two systematic reviews to address a significant gap in the evidence base identified by Luchenski et al. (2018) and by (White, 2018). The first review (which is the subject of this protocol) will use meta‐analysis to examine the effectiveness of different psychosocial interventions in (1) reducing problematic substance use; (2) improving mental health; and (3) improving housing stability for adults experiencing homelessness. The second review (which is covered by a separate title registration and protocol) will be of the experiences of adults experiencing homelessness when accessing or using psychosocial interventions, and will be a qualitative evidence synthesis using thematic synthesis (Thomas & Harden, 2008).
New efficient Hadoop scheduler: Generalized particle swarm optimization and simulated annealing‐dominant resource fairness
Authors: Sharma Sonia , Bharti Rajendra Kumar
Published: November 2022

Digital growth during the Corona pandemic has generated massive data. The Hadoop in big data has to be more efficient in resource handling and job scheduling. This article proposes the improved job scheduler which is more efficient in fair job scheduling even with the heterogeneous resources. The faster job execution depends upon the localization too. The nearer the slots are, the faster is the execution. So, this article proposes a hybrid metaheuristic algorithm with fair scheduling and data locality as the two objectives in job scheduling. The dominant resource fairness policy in Hadoop YARN is updated by hybrid generalized particle swarm optimization and simulated annealing for minimum locality and maximum fairness in scheduling. The algorithm is tested on various workloads for heterogeneous resources.
Magnetic Field‐Enhanced Electrocatalytic Oxygen Evolution on a Mixed‐Valent Cobalt‐Modulated LaCoO3 Catalyst
Authors: Wang Ting , He Haocheng , Meng Zihan , Li Siran , Xu Ming , Liu Xueting , Zhang Yuan , Liu Mei , Feng Ming
Published: November 2022

Extensive efforts to enhance the oxygen evolution reaction (OER) catalytic performance of transition metal oxides mainly concentrate on the extrinsic morphology tailoring, lattice doping, and electrode interface optimizing. Nevertheless, little room is left for performance improvement using these methods and an obvious gap still exists compared to the precious metal catalysts. In this work, a novel “mixed‐valent cobalt modulation” strategy is presented to enhance the electrocatalytic OER of perovskite LaCoO3 (LCO) oxide. The valence transition of cobalt is realized by ethylenediamine post reduction procedure at room temperature, which further induces the variation of magnetic properties for LCO catalyst. The optimized LCO catalyst with Co2+/Co3+ of 1.98 % exhibits the best OER activity, and the overpotential at 10 mA cm−2 current density is decreased by 170 mV compared pristine LCO. Impressively, the ferromagnetic LCO catalyst can perform magnetic OER enhancement. By application of an external magnetic field, the overpotential of LCO at 10 mA cm−2 can be further decreased by 20 mV compared to that of under zero magnetic field, which arises from the enhanced energy states of electrons and accelerated electron transfer process driven by magnetic field. Our findings may provide a promising strategy to break the bottleneck for further enhancement of OER performance.
A fully digital open‐loop clock and data synchronizer for ultra‐low power super‐regenerative receivers
Authors: Abbaszadeh Saber , Jalali Mohsen
Published: November 2022

In this paper, a clock and data synchronizer (CDS) is presented to improve channel selectivity of digitally assisted super‐regenerative receivers (SRRs). The proposed CDS performs phase and frequency adjustment of the quench signal using a fully digital open‐loop architecture removing the need for conventional phase‐locked loop (PLL) architectures. The required signal shaping of the recovered data is also performed by the proposed CDS to restore the nonreturn‐to‐zero data format without using any pulse width expander or sample and hold circuit. A multichannel SRR is implemented employing the proposed CDS where a Q‐enhancement procedure is also adopted to further improve the channel selectivity. The proposed SRR operates at 2.4‐GHz ISM band and supports a data rate of 1 Mb/s, while the sensitivity is about −88 dBm, and the selectivity is better than −18 dB at a 10‐MHz offset frequency. Implemented using a 0.18‐μm standard CMOS process and with a 1.1‐V supply voltage, the proposed SRR consumes about 0.4 mW.
The study on the comparative responses of aquatic vegetation to the interannual water level variation in different hydrologically connected sub‐lakes based on GEE technology
Authors: Chen Wenbo , Zhang Fuqing , Shang Xue , Wang Huan , He Lei
Published: November 2022

Water level variation is considered as a main controlling environment factor affecting the growth of aquatic vegetation in Poyang Lake, the largest freshwater lake in China. It is significant to study the influences of water level change on aquatic vegetation under various hydrological conditions. Taking the free connected sub‐lake Bang Lake and partially controlled sub‐lake Dahuchi Lake of Poyang Lake as research objects and based on the cloud computing platform of remote sensing of Google Earth Engine (GEE), the pixel binary model method was used to estimate the aquatic vegetation cover from 2000 to 2019, and the spatial and temporal variation characteristics were discovered first. Meanwhile, the combined method of Sen + M‐K (Theil–Sen Median method and Mann‐Kendall trend test) was conducted to simulate the trends of water fluctuation. Second, the hydrological parameters indicating water level fluctuation were established, and the relationship between these parameters and the area covered by aquatic vegetation in different sub‐lakes was explored. The results were as follows. (1) The aquatic vegetation cover of the freely connected sub‐lake Bang Lake was more susceptible to water level changes, while the partially controlled sub‐lake Dahuchi Lake was relatively stable underwater level change. (2) The aquatic vegetation was patchily and sporadically distributed in years with low vegetation cover, while in the years with high vegetation cover, it was distributed in a ringlike pattern, spreading from the centre of the lake to the shore. (3) The aquatic vegetation cover of the freely connected sub‐lake Bang Lake was more likely to be influenced by the water level fluctuation (WLF), while the aquatic vegetation cover of the partially controlled sub‐lake Dahuchi Lake was more likely to be influenced by the flooding duration of 17 m water level (L17). The flooding duration of 19 m water level (L19) had a strong negative correlation with the predicted aquatic vegetation cover of both Bang Lake and Dahuchi Lake. It suggests that there was a certain degree of time lag in the effect of water level changes on the free connected sub‐lakes, but there was no obvious time lag on the partially controlled sub‐lakes. (4) The aquatic vegetation of the freely connected sub‐lake Bang Lake were dominated by stabilization and slight improvement, while aquatic vegetation in the partially controlled sub‐lake Dahuchi Lake were dominated by stabilization and significant degradation. This study can help to further understand the vegetation changes in hydro‐ecological system with different hydrological connectivity and will provide a reference for lake management and conservation.
Synthesis of Functionalized Heteroleptic Germylene Alkoxides
Authors: Vítek Dominik , Růžička Aleš , Dostál Libor , Jambor Roman
Published: November 2022

N‐coordinated Ge(II) alkoxides L1(tBuO)Ge (1), L2(tBuO)Ge (2) and [L2(OtBu)Ge ⋅ BH3] (4) were prepared. Effect of either chelating ligands L1 and L2 or Ge→B interaction on strength of the Ge−OtBu bond was studied by insertion reaction of PhNCO. As a result, the Ge(II) carbamate L2{[(tBuO)OC](Ph)N}Ge (3) was isolated. Alcoholysis exchange reactions of 1 and 2 with substituted phenols were studied to find an easy synthetic protocol for a synthesis of functionalized Ge(II) alkoxides. Reactions yielded Ge(II) alkoxides L1,2(2‐Br−C6H4O)Ge (5 for L1, 8 for L2), L1,2(2‐MeNH−C6H4O)Ge (6 for L1, 9 for L2), L1,2(2‐Ph2P−C6H4O)Ge (7 for L1, 10 for L2), L2(2‐Br‐3‐OH−C6H3O)Ge (11) and L2(2‐NC5H4O)Ge (12) containing the additional polar groups Y (Y=Br, MeNH, PPh2, OH or N). Finally, phosphane decorated Ge(II) alkoxides 7 and 10 were tested as suitable ligands in reactions with (COD)W(CO)4 and BH3. As a consequence, new complexes [(κ2‐7)W(CO)4] (13) and [L1(2‐Ph2P ⋅ {BH3}‐C6H4O)Ge ⋅ {BH3}] (14) were isolated. All compounds were characterized by NMR and IR spectroscopy, and compounds 3, 4, 9 and 11 were additionally characterized by X‐ray diffraction analysis.
A new Distinct Element meso‐model for simulating the rocking‐dominated seismic response of RC columns
Authors: Scattarreggia Nicola , Malomo Daniele , DeJong Matthew J.
Published: November 2022

The rocking‐dominated seismic response of reinforced concrete (RC) columns is a complex mechanism that entails P‐Δ effects, concrete crushing and spalling, rupture and dislocation of steel bars and stirrups, as well as combined localized failures causing splitting and shear‐flexure cracking. In this paper, we present a new meso‐scale numerical modeling strategy for the detailed simulation of the rocking response of slender RC columns under seismic actions. This work advances the current state‐of‐the‐art by exploring the unprecedented use of the Distinct Element Method (DEM), originally conceived for geotechnical studies and whose applicability in earthquake engineering has been primarily limited to the assessment of unreinforced masonry sub‐structures. To decrease analysis time and enable the use of DEM for RC problems, concrete is herein idealized as an assembly of solid macro‐block layers of size directly proportional to their distance from expected plastic hinges. These layers are connected by nonlinear interface springs to simulate tensile and shear cracking via a simplified Mohr‐Coulomb criterion. Crushing of concrete in deformable blocks is modeled using the Feenstra and De Borst strain‐softening linearized compression law, while confinement and combined failures are accounted for numerically through the explicit representation of longitudinal and transversal reinforcement bars, idealized as link elements. Previous experimental static and dynamic tests on full‐scale RC column specimens and results from fiber‐based Finite Element and sectional analysis models are used to evaluate DEM results and quantify the influence of key modeling parameters, including block number and deformability, as well as the amount of damping. The agreement between simulated failure modes and force and displacement capacities and their experimental counterparts demonstrate the applicability of the proposed approach, while demonstrating the pros and cons of simplified numerical methods.
Stability of associations between neuroticism and microstructural asymmetry of the cingulum during late childhood and adolescence: Insights from a longitudinal study with up to 11 waves
Authors: Plachti Anna , Baaré William F. C. , Johansen Louise Baruël , Thompson Wesley K. , Siebner Hartwig R. , Madsen Kathrine Skak
Published: November 2022

Adolescence is characterized by significant brain development and marks a period of the life span with an increased incidence of mood disorders, especially in females. The risk of developing mood disorders is also higher in individuals scoring high on neuroticism, a personality trait characterized by a tendency to experience negative and anxious emotions. We previously found in a cross‐sectional study that neuroticism is associated with microstructural left–right asymmetry of the fronto‐limbic white matter involved in emotional processing, with opposite effects in female and male adolescents. We now have extended this work collecting longitudinal data in 76 typically developing children and adolescents aged 7–18 years, including repeated MRI sampling up to 11 times. This enabled us, for the first time, to address the critical question, whether the association between neuroticism and frontal‐limbic white matter asymmetry changes or remains stable across late childhood and adolescence. Neuroticism was assessed up to four times and showed good intraindividual stability and did not significantly change with age. Conforming our cross‐sectional results, females scoring high on neuroticism displayed increased left–right cingulum fractional anisotropy (FA), while males showed decreased left–right cingulum FA asymmetry. Despite ongoing age‐related increases in FA in cingulum, the association between neuroticism and cingulum FA asymmetry was already expressed in females in late childhood and remained stable across adolescence. In males, the association appeared to become more prominent during adolescence. Future longitudinal studies need to cover an earlier age span to elucidate the time point at which the relationship between neuroticism and cingulum FA asymmetry arises.
A modified threshold score‐based multilevel thresholding segmentation technique for brain magnetic resonance images using opposition‐based learning hybrid rice optimization algorithm
Authors: Ye Zhiwei , Song Zilun , Li Pengfei , Wang Mingwei , Hou Wenguang
Published: November 2022

In modern clinical diagnostics, magnetic resonance imaging (MRI) is frequently used for brain tumor detection because of its high resolution of soft tissues, which plays a crucial role in the prevention, detection, and treatment planning. Therefore, it is meaningful to obtain high‐quality MR images by automatic thresholding for aiding diagnosis. Most multilevel thresholding techniques are based on histograms. It is susceptible to the limitation of grayscale spatial distribution and is difficult to be used for MR images with variable and complex morphology. In this paper, a novel multilevel thresholding segmentation approach with a non‐histogram using a modified threshold score (MTS) is proposed. An opposition‐based learning hybrid rice optimization (OHRO) algorithm is used to reduce the computational cost of MTS for the purpose of optimizing the threshold search. The strategy of opposition‐based learning expands the space of feasible solutions and avoids the search from stalling. The proposed approach is evaluated through the Harvard Medical School's whole brain atlas dataset. Comparing the results with TS‐OHRO, Tsallis‐OHRO, Kapur‐OHRO, and Masi‐OHRO, MTS‐OHRO achieves better quantitative and qualitative outcomes which demonstrate that the application of MTS‐OHRO to MR images is effective and feasible.
Clinical pathways and diagnostic reasoning: A qualitative study of pediatric residents' and hospitalists' perceptions
Authors: Fatemi Yasaman , Costello Anna , Lieberman Leora , Hart Jessica , Shaw Kathy N. , Shea Judy A. , Coffin Susan
Published: November 2022

Background

Clinical pathways are evidence‐based guidelines adapted to local settings. They have been shown to improve patient outcomes and reduce resource utilization. However, it is unknown how physicians integrate clinical pathways into their clinical reasoning.

Methods

We conducted a single‐center qualitative study involving one‐on‐one semi‐structured interviews of pediatric residents and pediatric hospitalist attendings between August 2021 and March 2022. Interviews were audio‐recorded and professionally transcribed. We utilized a qualitative descriptive framework to code data and identify themes.

Results

We interviewed 15 pediatric residents and 12 pediatric hospitalists. Thematic analysis of interview transcripts revealed four themes related to physician utilization of and experience with clinical pathways: (1) utility as a tool, (2) means of standardizing care, (3) reflection of institutional culture, and (4) element of the dynamic relationship with the clinician diagnostic process. These themes were generally common to both residents and attending physicians; however, some differences existed and are noted when they occurred.

Conclusions

Clinical pathways are part of many clinicians' diagnostic processes. Pathways can standardize care, influence the diagnostic process, and express local institutional culture. Further research is required to ascertain the optimal clinical pathway design to augment and not inhibit the clinician's diagnostic process.
Normal Values of Magnetic Resonance T1ρ Relaxation Times in the Adult Heart at 1.5 T MRI
Authors: Deng Wei , Xue Yangcheng , Li Yuguo , An Shutian , Zheng Jie , Qian Yinfeng , Yue Xiuzheng , Wu Zhigang , Yu Yongqiang , Zhao Ren , Li Xiaohu
Published: November 2022

Background

T1ρ mapping is a new quantitative MRI technique in recent years. In order to use T1ρ mapping as a noncontrast method to assess myocardial fibrosis, it is necessary to establish a range of normal values.

Purpose

To establish a potential normal range of cardiac T1ρ values in healthy adults and to explore the influence of slice location and gender on T1ρ values.

Study Type

Prospective.

Population

A total of 57 healthy volunteers without cardiovascular risk factors (age 26.7 ± 11.8 years; 29 males).

Field Strength/Sequence

1.5 T; modified Look‐Locker inversion recovery (MOLLI) (T1 mapping), multiecho gradient‐spin‐echo (GraSE) (T2 mapping) and T1ρ‐prepared steady‐state free precession (T1ρ mapping) sequences.

Assessment

Basal, mid, and apical short‐axis left ventricular T1, T2, and T1ρ maps were acquired. T1ρ maps at spin‐locking frequencies of 5 and 400 Hz were subtracted to create myocardial fibrosis index (mFI) maps. Slice‐average and global average T1, T2, T1ρ, and mFI values were determined.

Statistical Tests

Shapiro–Wilk test, Independent t‐test, ANOVA test, Pearson correlation coefficient (r). Significance: P value < 0.05.

Results

The global average values of T1, T2, T1ρ, and mFI were 1053 ± 34 msec, 51.9 ± 2.3 msec, 47.9 ± 2.8 msec, and 4.4 ± 1.6 msec. T1ρ values showed a significant gradual increase from the basal slice to the apical slice of the heart (basal 46.5 ± 2.7 msec, mid 48.0 ± 2.9 msec, apical 49.2 ± 3.3 msec). The T1ρ and mFI values of females (49.7 ± 2.4 msec and 5.1 ± 1.2 msec, respectively) were significantly higher than those of males (46.2 ± 1.9 msec and 3.7 ± 1.7 msec, respectively). In addition, there was a moderate positive correlation between global T1ρ values and global T1 values (r = 0.44, P < 0.05) and a moderate positive correlation between global T1ρ values and global T2 values (r = 0.42, P < 0.05).

Data Conclusion

In this study, the global T1ρ values of healthy adults' hearts were 47.9 ± 2.8 msec. This study found that gender and slice location of myocardium can affect the T1ρ values.

Evidence Level

4

Technical Efficacy

Stage 1
Development of an HiBiT‐tagged reporter H3N2 influenza A virus and its utility as an antiviral screening platform
Authors: Zhang Chengcheng , Zhang Guoying , Zhang Yu , Lin Xiaojing , Zhao Xiujuan , Cui Qinghua , Rong Lijun , Du Ruikun
Published: November 2022

The balance of the segmented genome derived from naturally occurring influenza A viruses (IAVs) is delicate and vulnerable to foreign insertions, thus most reporter IAVs up to date are generated using the backbone of the laboratory‐adapted strains. In this study, we constructed a reporter influenza A/H3N2 virus (A/NY‐HiBiT) which was derived from a clinical isolate, by placing a minimized HiBiT tag to the N‐terminus of the viral nuclear‐export protein (NEP). Here, we show that this 11‐amino acid HiBiT tag did not adversely impact the viral genome balance, and the recombinant A/NY‐HiBiT virus maintains its relative stability. Moreover, the replication profile of the HiBiT‐tagged virus can be measured by a simple Nano‐Glo assay, providing a robust high‐throughput screening (THS) platform. We used this platform to evaluate a collection of the pre‐purified fractions which were derived from rare Chinese medicinal materials, and we identified three fractions, including wild Trametes robiniophila (50% methanol fraction), Ganoderma (water fraction), and wild Phellinus igniarius (ethyl acetate fraction), as potent anti‐IAV actives. Our results demonstrate that this IAV reporter can be used as a powerful HTS platform for antiviral development.
Nuclear magnetic resonance spectroscopy and liquid chromatography–mass spectrometry metabolomics studies on non‐organic soybeans versus organic soybeans (Glycine max), and their fermentation by Rhizopus oligosporus
Authors: Chong Siok‐Geok , Ismail Intan S , Ahmad Azam Amalina , Tan Shih‐Jen , Shaari Khozirah , Tan Jen‐Kit
Published: November 2022

Background

Soybeans (Glycine max) are high in proteins and isoflavones, which offer many health benefits. It has been suggested that the fermentation process enhances the nutrients in the soybeans. Organic foods are perceived as better than non‐organic foods in terms of health benefits, yet little is known about the difference in the phytochemical content that distinguishes the quality of organic soybeans from non‐organic soybeans. This study investigated the chemical profiles of non‐organic (G, T, U, UB) and organic (C, COF, A, R, B, Z) soybeans (G. max [L.] Merr.) and their metabolite changes after fermentation with Rhizopus oligosporus.

Results

A clear separation was only observed between non‐organic G and organic Z, which were then selected for further investigation in the fermentation of soybeans (GF and ZF). All four groups (G, Z, GF, ZF) were analyzed using nuclear magnetic resonance (NMR) spectroscopy along with liquid chromatography–tandem mass spectrometry (LC–MS/MS). In this way a total of 41 and 47 metabolites were identified respectively, with 12 in common. A clear variation (|log1.5FC| > 2 and P < 0.05) was observed between Z and ZF: most of the sugars and isoflavone glycosides were found only in Z, while more amino acids and organic acids were found in ZF. An additional four metabolites clustered as C‐glycosylflavonoids were discovered from MS/MS‐based molecular networking.

Conclusion

Chemical profiles of non‐organic and organic soybeans exhibited no significant difference. However, the metabolite profile of the unfermented soybeans, which were higher in sugars, shifted to higher amino acid and organic acid content after fermentation, thereby potentially enhancing their nutritional value. © 2022 Society of Chemical Industry.