bluuebunny/crossref_metadata_2025_split huggingface dataset:
Thermodynamics and kinetics of intracellular ice formation during freezing of biological cells
Authors: Toner Mehmet , Cravalho Ernest G. , Karel Marcus 
Published: July 2002

A physicochemical model based on the modified classical heterogeneous nucleation theory was proposed to analyze the ice formation inside biological cells during freezing. According to this model, intracellular ice formation (IIF) may be catalyzed either by the plasma membrane via the effects of the external ice on the plasma membrane, called surface-catalyzed nucleation (SCN), or by the intracellular particles, called volume-catalyzed nucleation (VCN), depending on the freezing conditions. The model for IIF was coupled with the model describing the kinetics of water transport to predict the thermodynamic state of the cytoplasm.
A method to estimate the nucleation frequency from the observed probability of nucleation was suggested. This method was based on the assumption that each cell has the same heteronucleating particles with identical properties to alter the nucleation kinetics in an identical way. This allowed the correlation of the experimental probability of IIF with the nucleation rate. It was suggested that the uncertainties in the experimental conditions could be minimized if cells were cooled at rapid rates to prevent water transport during freezing. The model was applied to mouse oocytes at metaphase II. Correlation of the theory with the experimental kinetics of the cumulative fraction of IIF revealed preexponentional factors of 3.56×108 (m2 s)−1 and 1.84×1050 (m3 s)−1, and exponential factors of 4.6×109 and 1.08×1012 K5 for SCN and VCN, respectively. The contact angle between the internal surface of the plasma membrane and the ice cluster for SCN, θ, was determined to be 35° for freezing in isotonic solutions (285 mosm) increasing linearly to 47° in hypertonic solutions (1035 mosm). SCN was active between ∼−5 and −20 °C in the presence of external ice. It is suggested that the presence of external ice alters the plasma membrane through its chemical, electrical, mechanical, ionic, and thermal effects, to make it an energetically favorable site for heterogeneous nucleation. For VCN, lower and upper limits for θ and R were found to be 60°&lt;θ&lt;100° and 10−7&lt;R&lt;4×10−7 cm, respectively. VCN was active between ∼−30 and −35 °C.
Feasibility of using ring‐mounted Halcyon Linac for single‐isocenter/two‐lesion lung stereotactic body radiation therapy
Authors: Pokhrel Damodar , Webster Aaron , Mallory Richard , Visak Justin , Bernard Mark E. , McGarry Ronald C. , Kudrimoti Mahesh 
Published: February 2022

AbstractPurposeTo demonstrate the plan quality and delivery efficiency of volumetric‐modulated arc therapy (VMAT) with the Halcyon Linac ring delivery system (RDS) in the treatment of single‐isocenter/two‐lesion lung stereotactic body radiation therapy (SBRT).Materials/methodsSixteen previously treated non‐coplanar VMAT single‐isocenter/two‐lesion lung SBRT plans delivered with SBRT‐dedicated C‐arm TrueBeam Linac were selected. Prescribed dose was 50 Gy to each lesion over five fractions with treatment delivery every other day and AcurosXB algorithm as the final dose calculation algorithm. TrueBeam single‐isocenter plans were reoptimized for Halcyon Linac with coplanar geometry. Both TrueBeam and Halcyon plans were normalized for identical combined target coverage and evaluated. Conformity indices (CIs), heterogeneity index (HI), gradient index (GI), gradient distance (GD), and D2cm were compared. The normal lung V5Gy, V10Gy, V20Gy, mean lung dose (MLD), and dose to organs at risk (OAR) were evaluated. Treatment delivery parameters, including beam‐on time, were recorded.ResultsHalcyon plans were statistically similar to clinically delivered TrueBeam plans. No statistical differences in target conformity, dose heterogeneity, or intermediate‐dose spillage were observed (all, p > 0.05). Halcyon plans, on average, demonstrated statistically insignificant reduced maximum dose to most adjacent OAR and normal lung. However, Halcyon yielded statistically significant lower maximal dose to the ribs (p = 0.041) and heart (p = 0.026), dose to 1 cc of ribs (p = 0.035) and dose to 5 cc of esophagus (p = 0.043). Plan complexity slightly increased as seen in the average increase of total monitor units, modulation factor, and beam‐on time by 480, 0.48, and 2.78 min, respectively. However, the estimated overall treatment time was reduced by 2.22 min, on average. Mean dose delivery accuracy of clinical TrueBeam plans and the corresponding Halcyon plans was 98.9 ± 0.85% (range: 98.1%–100%) and 98.45 ± 0.99% (range: 97.9%–100%), respectively, demonstrating similar treatment delivery accuracy.ConclusionSBRT treatment of synchronous lung lesions via single‐isocenter VMAT on Halcyon RDS is feasible and dosimetrically equivalent to clinically delivered TrueBeam plans. Halcyon provides excellent plan quality and shorter overall treatment time that may improve patient compliance, reduce intrafraction movement, improve clinic efficiency, and potentially offering lung SBRT treatments for underserved patients on a Halcyon only clinic.
A Variable Stiffness Magnetic Catheter Made of a Conductive Phase‐Change Polymer for Minimally Invasive Surgery
Authors: Piskarev Yegor , Shintake Jun , Chautems Christophe , Lussi Jonas , Boehler Quentin , Nelson Bradley J. , Floreano Dario 
Published: February 2022

AbstractVariable stiffness (VS) is an important feature that significantly enhances the dexterity of magnetic catheters used in minimally invasive surgeries. Existing magnetic catheters with VS consist of sensors, heaters, and tubular structures filled with low melting point alloys, which have a large stiffness change ratio but are toxic to humans. In this paper, a VS magnetic catheter is described for minimally invasive surgery; the catheter is based on a novel variable stiffness thread (VST), which is made of a conductive shape memory polymer (CSMP). The CSMP is nontoxic and simultaneously serves as a heater, a temperature sensor, and a VS substrate. The VST is made through a new scalable fabrication process, which consists of a dipping technique that enables the fabrication of threads with the desired electrical resistance and thickness (with a step size of 70 µm). Selective bending of a multisegmented VST catheter with a diameter of 2.0 mm under an external magnetic field of 20 mT is demonstrated. Compared to existing proof‐of‐concept VS catheters for cardiac ablation, each integrated VST segment has the lowest wall thickness of 0.75 mm and an outer diameter of 2.0 mm. The segment bends up to 51° and exhibits a stiffness change factor of 21.
An MXene‐Based Metal Anode with Stepped Sodiophilic Gradient Structure Enables a Large Current Density for Rechargeable Na–O2 Batteries
Authors: He Xin , Ni Youxuan , Li Yixin , Sun Haoxiang , Lu Yong , Li Haixia , Yan Zhenhua , Zhang Kai , Chen Jun 
Published: February 2022

AbstractThe metal anode is the pivotal component for advanced sodium‐metal batteries such as Na–O2 batteries. Designing a 3D confinement scaffold is a promising strategy for constructing dendrite‐free sodium‐metal anodes; however, cycling stability at a large current density (>10 mA cm−2) is still difficult to realize. Herein, the design of new lightweight and fibrous hydroxylated Ti3C2 (h‐Ti3C2) MXene based scaffolds with stepped sodiophilic gradient structure (h‐M‐SSG) is reported, and its thickness can be controlled (80−250 µm). The sodiophilic gradient structure (adjusted by h‐Ti3C2) can effectively induce sodium ions to preferentially deposit at the bottom of the scaffold, thus inhibiting dendrite growth. h‐M‐SSG/Na‐based symmetrical batteries exhibit a low polarization voltage and long cycling life at a high current density (40 mA cm−2) and a high cut‐off capacity (40 mAh cm−2). Moreover, a Na–O2 battery with an h‐M‐SSG/Na anode exhibits a low potential gap of 0.137 V after 45 cycles at 1000 mA g−1 and 1000 mAh g−1. This deposition‐regulation strategy would inspire the design of 3D scaffolds for high‐performance sodium‐metal‐anode‐based batteries.
Significant Enhancement on the Proton Conduction Performance of Composite Membrane by Photoacid Molecules
Authors: Zhou Shu‐Fang , Wu Guo‐Mei , Zhang Chen‐Xi , Wang Qing‐Lun 
Published: February 2022

AbstractMimicking biological proton pump phenomenon to achieve stimulus‐responsive proton conduction behavior has received long‐term attention. The Pa@Zn‐MOF (Pa = photoacids) composites are successfully prepared through adsorption photoacid in Zn‐MOF, then, the composites are mixed into poly(vinyl alcohol) (PVA) to fabricate hybrid membranes Pa@Zn‐MOF‐PVA. When the hybrid membrane is activated through 375 nm violet light at room temperature, the value of proton conductivity after illumination is always superior to that before light irradiation. This phenomenon is attributed to the light‐induced ring‐closing reaction of the photoacid molecules to give the spiro‐forms (SPs) along with an abundant release of protons. The released protons jump into hydrogen bond networks and conveniently accelerate proton transport, resulting in higher proton conductivity. This is a noteworthy demonstration of dynamic control over proton conduction in composite membrane materials by adsorption of photoacid molecules in metal–organic framework.
Boosting Enhancement of the Electron–Phonon Coupling in Mixed Dimensional CdS/Graphene van der Waals Heterojunction
Authors: Li Zhonglin , Guo Shuai , Weller Dieter , Quan Sufeng , Yu Jing , Wang Runqiu , Wu Mengxuan , Jiang Jie , Wang Yingying , Liu Ruibin 
Published: February 2022

AbstractElectron–phonon coupling plays a key role in affecting the properties of the semiconducting nanostructures, such as providing the possibility for obtaining higher superconducting transition temperatures. Here, using Raman, temperature‐dependent and polarized Raman scattering measurements, ultra‐strong electron–phonon coupling in 1D CdS nanowires and 2D graphene heterostructures is demonstrated. The intensity ratio of 2LO/1LO mode in CdS nanowires provides a spectroscopy‐based method to quantify electron–phonon coupling, the strength of which is temperature and polarization dependent. The intensity ratio mode of 2LO/1LO in heterostructure reached up to 8.95 when the incident laser polarization is parallel to the c‐axis of the nanowire. It is ≈2.37 times higher than in an individual nanowire. In addition, in situ and time‐resolved photoluminescence spectra demonstrate the dynamics of the exciton recombinations, providing a comprehensive understanding of the enhancement of electron–phonon coupling in heterostructures. Via optical waveguiding characterization, the graphene layer is demonstrated to not only be an ultrafast carrier transfer channel but also a low Fermi level channel that induces the formation of the built in electrical field, elevating the electron–phonon coupling. Such new mixed dimensional heterostructures illustrate a straightforward approach to enhance the electron–phonon coupling, which may be applied to many integrated superconducting photonic and optoelectronic devices.
Survey of Tetragonal Transition Metal Chalcogenide Hetero‐Bilayers for Promising Photocatalysts
Authors: Zhou Jia , Cheng Yanxin , Zhu Yaoyun 
Published: February 2022

AbstractThe formation of van der Waals (vdW) hetero‐bilayers have been emerging as unique structures to improve the performance of 2D layered nanomaterials for next‐generation photocatalysts. In this work, first‐principles calculations are employed to study the electronic and optical properties of a variety of tetragonal transition metal chalcogenide hetero‐bilayers. It is found that there are three stable semiconductor/semiconductor vdW hetero‐bilayers, and twenty‐one stable semiconductor/conductor vdW hetero‐bilayers. It is revealed that ZnS/ZnSe and ZnSe/ZnTe hetero‐bilayers possess a special band characteristic that is favorable for reducing the carrier recombination. In semiconductor/conductor hetero‐bilayers, the band edges of semiconductor are tuned via Schottky barrier, including p‐type and n‐type Schottky barrier. This work suggests that all hetero‐bilayers have an enhanced optical absorption within the visible light region, leading to more efficient solar energy harvesting. Based upon the theoretical calculations, tetragonal transition metal chalcogenide hetero‐bilayers will be great candidates as high performance photocatalysts for solar water splitting, as well as many other optoelectronic applications.
High‐Performance Functional Fe‐MOF for Removing Aflatoxin B1 and Other Organic Pollutants
Authors: Liu Yu‐Qing , Song Cheng‐Gang , Ding Gang , Yang Jian , Wu Jia‐Rui , Wu Gengxin , Zhang Ming‐Zhe , Song Chunli , Guo Lan‐Ping , Qin Jian‐Chun , Yang Ying‐Wei 
Published: February 2022

AbstractOrganic pollutants, including mycotoxins, organic dyes, and pesticide residues, are the most critical threats to the global environment. In particular, efficient adsorption based on synthetic nanomaterials is considered a versatile and green approach to control mycotoxins. This work systematically investigates the aflatoxin B1 (AFB1) removal capacity of MIL‐101(Fe), a typical type of metal‐organic framework (MOF) synthesized by solvothermal methods and possesses super‐high porosity and excellent dispersion in liquid. The experimental results demonstrate that as‐prepared MIL‐101(Fe) exhibits a much higher saturated loading capacity (30.58 mg g−1) toward AFB1 than other adsorbents described in the literature. Subsequently, the adsorption process is studied via isothermal and kinetic analyses. This work also evaluates the removal effect of MIL‐101(Fe) on organic dyes and pesticides compared to the other five MOFs; the results reveal that MIL‐101(Fe) possesses a diversity of pollutant adsorption. The molecular docking and interaction region indicator analysis is applied to reflect the interactions between AFB1 molecules and MIL‐101(Fe). This work will provide a simple and effective approach for AFB1 treatment and adsorption in wastewaters and offer new insights and perspectives to the practical applications of synthetic nanomaterials, MOFs in environmental management.
Supramolecular Peptide Nanofiber Hydrogels for Bone Tissue Engineering: From Multihierarchical Fabrications to Comprehensive Applications
Authors: Hao Zhuowen , Li Hanke , Wang Yi , Hu Yingkun , Chen Tianhong , Zhang Shuwei , Guo Xiaodong , Cai Lin , Li Jingfeng 
Published: February 2022

AbstractBone tissue engineering is becoming an ideal strategy to replace autologous bone grafts for surgical bone repair, but the multihierarchical complexity of natural bone is still difficult to emulate due to the lack of suitable biomaterials. Supramolecular peptide nanofiber hydrogels (SPNHs) are emerging biomaterials because of their inherent biocompatibility, satisfied biodegradability, high purity, facile functionalization, and tunable mechanical properties. This review initially focuses on the multihierarchical fabrications by SPNHs to emulate natural bony extracellular matrix. Structurally, supramolecular peptides based on distinctive building blocks can assemble into nanofiber hydrogels, which can be used as nanomorphology‐mimetic scaffolds for tissue engineering. Biochemically, bioactive motifs and bioactive factors can be covalently tethered or physically absorbed to SPNHs to endow various functions depending on physiological and pharmacological requirements. Mechanically, four strategies are summarized to optimize the biophysical microenvironment of SPNHs for bone regeneration. Furthermore, comprehensive applications about SPNHs for bone tissue engineering are reviewed. The biomaterials can be directly used in the form of injectable hydrogels or composite nanoscaffolds, or they can be used to construct engineered bone grafts by bioprinting or bioreactors. Finally, continuing challenges and outlook are discussed.
Superelongation of Liquid Metal
Authors: Li Xiangpeng , Cao Lu , Xiao Bing , Li Fangxia , Yang Junhui , Hu Jie , Cole Tim , Zhang Yuxin , Zhang Mingkui , Zheng Jiahao , Zhang Shiwu , Li Weihua , Sun Lining , Chen Xiaoqian , Tang Shi‐Yang 
Published: February 2022

AbstractThe ability to control interfacial tension electrochemically is uniquely available for liquid metals (LMs), in particular gallium‐based LM alloys. This imparts them with excellent locomotion and deformation capabilities and enables diverse applications. However, electrochemical oxidation of LM is a highly dynamic process, which often induces Marangoni instabilities that make it almost impossible to elongate LM and manipulate its morphology directly and precisely on a 2D plane without the assistance of other patterning methods. To overcome these limitations, this study investigates the use of an LM–iron (Fe) particle mixture that is capable of suppressing instabilities during the electrochemical oxidation process, thereby allowing for superelongation of the LM core of the mixture to form a thin wire that is tens of times of its original length. More importantly, the elongated LM core can be manipulated freely on a 2D plane to form complex patterns. Eliminating Marangoni instabilities also allows for the effective spreading and filling of the LM–Fe mixture into molds with complex structures and small features. Harnessing these excellent abilities, a channel‐less patterning method for fabricating elastomeric wearable sensors is demonstrated to detect motions. This study shows the potential for developing functional and flexible structures of LM with superior performance.
Dielectric Loss Mechanism in Electromagnetic Wave Absorbing Materials
Authors: Qin Ming , Zhang Limin , Wu Hongjing 
Published: February 2022

AbstractElectromagnetic (EM) wave absorbing materials play an increasingly important role in modern society for their multi‐functional in military stealth and incoming 5G smart era. Dielectric loss EM wave absorbers and underlying loss mechanism investigation are of great significance to unveil EM wave attenuation behaviors of materials and guide novel dielectric loss materials design. However, current researches focus more on materials synthesis rather than in‐depth mechanism study. Herein, comprehensive views toward dielectric loss mechanisms including interfacial polarization, dipolar polarization, conductive loss, and defect‐induced polarization are provided. Particularly, some misunderstandings and ambiguous concepts for each mechanism are highlighted. Besides, in‐depth dielectric loss study and novel dielectric loss mechanisms are emphasized. Moreover, new dielectric loss mechanism regulation strategies instead of regular components compositing are summarized to provide inspiring thoughts toward simple and effective EM wave attenuation behavior modulation.
Photothermal‐Assisted Photocatalytic Nitrogen Oxidation to Nitric Acid on Palladium‐Decorated Titanium Oxide
Authors: Zhang Xuerui , Shi Run , Li Zhenhua , Zhao Jiaqing , Huang Huining , Zhou Chao , Zhang Tierui 
Published: February 2022

AbstractIndustrial nitric acid production involves multistep processes operating at high temperatures and pressures. Photocatalysis offers an alternative approach for directly transforming nitrogen molecules into nitrogen‐containing compounds under ambient conditions but still faces visible light utilization and product selectivity restrictions. Herein, a tandem photothermal‐assisted photocatalytic nitrogen oxidation system based on palladium‐decorated hydrogenated titanium oxide is fabricated, in which nitric acid is produced as the only nitrogen fixation product. The yield of nitric acid increases from 0.56 µmol g−1 h−1 at room temperature to 4.58 µmol g−1 h−1 (1.42 ppm) at 200 °C, accompanied by an enhanced quantum yield from 0.24% to 0.99% at 350 nm. The photothermal effect of palladium nanoparticles promotes the generation of superoxide radicals and nitrogen oxide intermediates in the gas–solid phase nitrogen oxidation process and contributes to improved nitric acid productivity. Therefore, the photothermal‐assisted photocatalytic nitrogen oxidation strategy opens new avenues toward developing clean and energy‐saving nitric acid production.
Trends in fatal occupational injuries in Latino/a workers relative to other groups, North Carolina 2000–2017
Authors: Richey Morgan M. , Golightly Yvonne , Marshall Stephen W. , Novicoff Wendy , Keil Alexander P. , Nocera Maryalice , Richardson David B. 
Published: February 2022

AbstractBackgroundLatino/a workers may experience higher fatal occupational injury rates than non‐Latino/a workers. In North Carolina, the Latino/a population more than doubled between 2000 and 2017. We examined fatal occupational injuries among Latino/a and non‐Latino/a workers in North Carolina over this period.MethodsInformation on fatal occupational injuries was abstracted from records of the North Carolina Office of the Chief Medical Examiner and the death certificate records held by the North Carolina Office of Vital Records. Estimates of the working population were derived from the decennial census and American Community Survey. Estimates of annual rates of fatal occupational injury for the period January 1, 2000 to December 31, 2017 were derived for Latino/a workers and compared to Black and White workers not identified as Latino/a.ResultsOver the study period, 1,783 fatal occupational injuries were identified among non‐Latino/a workers and 259 fatal occupational injuries among Latino/a workers in North Carolina. The majority of fatal occupational injuries among Latino/a workers occurred among males employed in construction and agriculture. While the fatal occupational injury rate among Latino/a workers declined over the study period, the rate among Latino/a workers was higher than among non‐Latino/a White and Black workers; moreover, fatal occupational injury rates for Latino/a workers trended upwards during the most recent years of the study period.ConclusionsLatino/a workers in North Carolina have the highest fatal occupational injury rate of any race/ethnicity group.
Oriented Nanoarchitectonics of Bacteriorhodopsin for Enhancing ATP Generation in a FoF1‐ATPase‐Based Assembly System
Authors: Li Zibo , Xu Xia , Yu Fanchen , Fei Jinbo , Li Qiang , Dong Mingdong , Li Junbai 
Published: February 2022

AbstractEnergy conversion plays an important role in the metabolism of photosynthetic organisms. Improving energy transformation by promoting a proton gradient has been a great challenge for a long time. In the present study, we realize a directional proton migration through the construction of oriented bacteriorhodopsin (BR) microcapsules coated by FoF1‐ATPase molecular motors through layer‐by‐layer (LBL) assembly. The changes in the conformation of BR under illumination lead to proton transfer in a radial direction, which generates a higher proton gradient to drive the synthesis of adenosine triphosphate (ATP) by FoF1‐ATPase. Furthermore, to promote the photosynthetic activity, optically matched quantum dots were introduced into the artificial coassembly system of BR and FoF1‐ATPase. Such a design creates a new path for the use of light energy.
Direct Dehydrogenative Access to Unsymmetrical Phenones
Authors: Yu Congjun , Huang Raolin , Patureau Frederic W. 
Published: February 2022

AbstractThe first non‐directed dehydrogenative phenone coupling method of methylarenes with aromatic C−H bonds, displaying a large substrate scope, is herein reported. This reaction represents a far more direct atom‐ and step‐efficient alternative to the classical Friedel–Crafts or Suzuki–Miyaura derived acylation reactions. The method can be carried out on a gram scale and was successfully applied to the synthesis of several Ketoprofen drug analogues.