644,825 results match your criteria physics


Designing architectural materials: from granular form to functional granular material.

Bioinspir Biomim 2021 Sep 23. Epub 2021 Sep 23.

Institute for Computational Design, Universitat Stuttgart, Keplerstrasse 11, 70174 Stuttgart, Stuttgart, 70174, GERMANY.

Designed granular materials are a novel class of architectural material system. Following one of the key paradigms of designed matter, material form and material function are closely interrelated in these systems. In this context, the article aims to contribute a parametric particle design model as an interface for this interrelation. Read More

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September 2021

The structural, magnetic, Raman and electrical transport properties Mn intercalation in TiCT.

J Phys Condens Matter 2021 Sep 23. Epub 2021 Sep 23.

School of Physics and Optics, South China University of Technology, School of Physics and Optics, South China University of Technology, Guangzhou, 510640, CHINA.

The electronic and magnetic properties of the two-dimensional TiCMXenes have attracted a lot of interests due to its potential applications. In this paper, TiCTMXenes and Mn-doped TiCTMXenes are synthesized and investigated. The experimental data shows that Mnions are homogeneously and randomly intercalated between TiCsheets as function terminals, which increase the interlayer distance between TiCsheets and offer a mass of uncoupled magnetic moment. Read More

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September 2021

Towards the characterization of neutron carcinogenesis through direct action simulations of clustered DNA damage.

Phys Med Biol 2021 Sep 23. Epub 2021 Sep 23.

Medical Physics Unit, McGill University, DS1.7141, Cedars Cancer Centre, 1001 boul Décarie, Montreal, Quebec, H4A 3J1, CANADA.

Neutron exposure poses a unique radiation protection concern because neutrons have a large, energy-dependent relative biological effectiveness (RBE) for stochastic effects. Recent computational studies on the microdosimetric properties of neutron dose deposition have implicated clustered DNA damage as a likely contributor to this marked energy dependence. So far, publications have focused solely on neutron RBE for inducing clusters of DNA damage containing two or more DNA double strand breaks (DSBs). Read More

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September 2021

Generation of circular spin current in an AB magnetic ring with vanishing net magnetization: A new prescription.

J Phys Condens Matter 2021 Sep 23. Epub 2021 Sep 23.

Physics and Applied Mathematics Unit, Indian Statistical Institute, Kolkata, 203 Barrackpore Trunk Road, Calcutta-700108, Kolkata, West Bengal, 700108, INDIA.

In this work we report for the first time the appearance of non-decaying circular spin current in a magnetic ring with vanishing net magnetization, even in absence of any spin chirality. Breaking the symmetry in hopping integrals we can misalign up and down spin electronic energy levels which yields a net spin current in the magnetic quantum ring, threaded by an Aharonov-Bohm (AB) flux. Along with spin current, a net charge current also appears, and we compute both these currents using the second quantized approach. Read More

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September 2021

A semi-classical theory of magnetic inelastic scattering in transmission electron energy loss spectroscopy.

Authors:
B G Mendis

Ultramicroscopy 2021 Sep 13;230:113390. Epub 2021 Sep 13.

Department of Physics, Durham University, South Road, Durham DH1 3LE, UK. Electronic address:

The feasibility of detecting magnetic excitations using monochromated electron energy loss spectroscopy in the transmission electron microscope is examined. Inelastic scattering cross-sections are derived using a semi-classical electrodynamic model, and applied to AC magnetic susceptibility measurements and magnon characterization. Consideration is given to electron probes with a magnetic moment, such as vortex beams, where additional inelastic scattering can take place due to the change in magnetic potential energy of the incident electron in a non-uniform magnetic field. Read More

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September 2021

Atmospheric ammonia and its effect on PM pollution in urban Chengdu, Sichuan Basin, China.

Environ Pollut 2021 Sep 16;291:118195. Epub 2021 Sep 16.

State Key Laboratory of Atmospheric Boundary Layer Physics and Atmospheric Chemistry (LAPC), Institute of Atmospheric Physics, Chinese Academy of Sciences, Beijing, 100011, China.

Controlling ammonia (NH) emissions has been proposed as a strategy to mitigate haze pollution. To explore the role of NH in haze pollution in Sichuan Basin, where agricultural activities are intense, hourly in situ data of NH, as well as nitric acid and secondary inorganic aerosols (SIAs) were gathered in Chengdu from April 2017 to March 2018. We found that NH had an annual mean concentration of 9. Read More

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September 2021

Long term Be deposition in Romania.

J Environ Radioact 2021 Sep 20;240:106738. Epub 2021 Sep 20.

Faculty of Physics, University of Bucharest, Strada, Atomiștilor 405, Magurele, 077125, Romania; Extreme Light Infrastructure - Nuclear Physics, IFIN-HH, 30 Atomistilor Str, Bucharest-Magurele, Romania. Electronic address:

This study is based on monthly Be deposition data at 29 of the stations of Romania's National Environmental Radioactivity Surveillance Network (NERSN), with different geographical and climatological conditions, extending over periods up to 17 years (1979-1995). The Be activity in each monthly sample from each station was determined using high-resolution gamma-ray spectrometry performed at the Environmental Radioactivity Laboratory, Bucharest-Afumati. The annual dynamics of atmospheric deposition of Be at each NERSN station showed a strong seasonal trend, very similar to the precipitation regime, with the highest values being observed in spring/summer and the lowest in winter. Read More

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September 2021

Understanding the hepatoxicity of inorganic mercury through guts: Perturbance to gut microbiota, alteration of gut-liver axis related metabolites and damage to gut integrity.

Ecotoxicol Environ Saf 2021 Sep 20;225:112791. Epub 2021 Sep 20.

CAS-HKU Joint Laboratory of Metallomics on Health and Environment, & CAS Key Laboratory for Biological Effects of Nanomaterials and Nanosafety, & Beijing Metallomics Facility, & National Consortium for Excellence in Metallomics, Institute of High Energy Physics, Chinese Academy of Sciences, Beijing 100049, China; University of Chinese Academy of Sciences, Beijing 100049, China. Electronic address:

Mercury (Hg) brings adverse effects to the environment and human beings and inorganic mercury (IHg) is a typical hepatic toxin. This work studied the impacts of IHg on gut microbes and metabolome together with its damage to liver and gut in rats through gut microbiome, metabolomics and metallomics. Sprague Dawley (SD) rats were orally exposed to 0. Read More

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September 2021

The molecular structure and spectroscopic properties of CHO and its isomers: An ab initio study.

Spectrochim Acta A Mol Biomol Spectrosc 2021 Sep 14;265:120388. Epub 2021 Sep 14.

Department of Physics, Baotou Teacher's College, Baotou 014030, China.

The spectroscopic parameters and anharmonic force fields of three isomers (c-HCO, HCCCHO and CHCCO) of CHO have been calculated by Density Functional Theory (B3LYP, CAM-B3LYP, wB97XD) and second-order Møller-Plesset perturbation theory (MP2) combining with 6-311++G (3df, 3pd) and aug-cc-pVTZ basis sets. The equilibrium geometries, energies, rotational constants, harmonic and fundamental frequencies, and centrifugal distortion constants of three isomers of CHO are calculated and compared with the existed results. The anharmonic constants, vibration-rotation interaction constants, Coriolis coupling constants and force constants of three isomers of CHO are firstly predicted. Read More

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September 2021

Quantification and mapping of fish waste in retail trade and restaurant sector: Experience in Emilia-Romagna, Italy.

Waste Manag 2021 Sep 20;135:256-266. Epub 2021 Sep 20.

University of Bologna, CIRSA - Interdepartmental Research Centre for Environmental Sciences, Via Sant'Alberto 163, 48123 Ravenna, Italy; University of Bologna, Department of Physics and Astronomy, Via Irnerio, 46, 40126 Bologna, Italy.

The circular economy approach imposes the complete recovery of components, materials and energy from waste. Many active compounds with biomedical and nutraceutical applications can be extracted by Fish Waste (FW), but few are the operating industrial plants. Quantification and mapping of the potential FW availability along the entire fish value-chain is crucial in fostering its actual valorisation. Read More

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September 2021

Structure of the K87 capsular polysaccharide and KL87 gene cluster of Acinetobacter baumannii LUH5547 reveals a heptasaccharide repeating unit.

Carbohydr Res 2021 Sep 7;509:108439. Epub 2021 Sep 7.

N. D. Zelinsky Institute of Organic Chemistry, Russian Academy of Sciences, Moscow, Russia.

K87 capsular polysaccharide (CPS) was isolated from Acinetobacter baumannii isolate LUH5547 that carries the KL87 capsule biosynthesis gene cluster at the chromosomal K locus. Studies by sugar analysis, selective chemical cleavages, and 1D and 2D H and C NMR spectroscopy showed that the CPS has a branched heptasaccharide repeat (K unit) containing one residue each of d-glucose (d-Glсp), d-glucuronic acid (d-GlсpA), N-acetyl-d-glucosamine (d-GlсpNAc), 6-deoxy-l-talose (l-6dTalp), and three residues of l-rhamnose (l-Rhap). The following structure of the CPS was established: →3)-α-L-Rhap-(1→2)-α-L-Rhap-(1→3)-α-L-6dTalp-(1→3)-β-D-GlcpNAc-(1→2↑1β-D-GlcpA-(4←1)-α-D-Glcp(2←1)-α-L-Rhap The position of a minor O-acetyl group present in the CPS was not determined. Read More

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September 2021

Constraints and divergent assessments of fertility in non-empirical physics in the history of the string theory controversy.

Authors:
Sophie Ritson

Stud Hist Philos Sci 2021 Sep 20;90:39-49. Epub 2021 Sep 20.

University of Sydney, Australia. Electronic address:

This paper examines historic appraisals of string theory to develop a less abstract understanding of the string theory controversy and assessment in non-empirical physics. This historical approach reveals several points of conflict in the controversy, each centring on a constraint. By proceeding stepwise through these constraints, I reveal the role that constraints played in determining divergent assessments of string theory. Read More

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September 2021

A heavy-ion production channel of Tb via Cu bombardment of Y.

Appl Radiat Isot 2021 Sep 14;178:109935. Epub 2021 Sep 14.

Department of Physics, University of Notre Dame, Notre Dame, IN, 46556, USA.

The radionuclide Tb (t = 4.1 h) is a potential theranostic isotope which can simultaneously be used for targeted-alpha-particle therapy and positron-emission tomography. Feasibility experiments were performed to test a near-symmetric heavy-ion reaction of Cu bombardment on monoisotopic Y. Read More

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September 2021

Towards a better mechanistic comprehension of drug permeation and absorption: introducing the diffusion-partitioning interplay.

Int J Pharm 2021 Sep 20:121116. Epub 2021 Sep 20.

Department of Pharmacy, Faculty of Mathematics and Natural Sciences, University of Oslo, Norway. Electronic address:

The process of passive drug absorption from the gastrointestinal tract is still poorly understood and modelled. Additionally, the rapidly evolving field of pharmaceutics demands efficient, affordable and reliable in vitro tools for predicting in vivo performance. In this work, we combined established methods for quantifying drug diffusivity (localized UV-spectroscopy) and permeability (Permeapad® plate) in order to gain a better understanding of the role of unstirred water layers (UWLs) in drug absorption. Read More

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September 2021

From fat to bilayers: Understanding where and how vitamin E works.

Free Radic Biol Med 2021 Sep 20. Epub 2021 Sep 20.

Department of Physics, and Centre for Bone and Muscle Health, Brock University, St. Catharines, ON, L2S3A1, Canada.

Vitamin E was one of the last fat-soluble vitamins to be discovered. We provide here an historical review of the discovery and the increasingly more detailed understanding of the role of α-tocopherol both as an antioxidant and as a structural component of phospholipid bilayer membranes. Despite the detailed descriptions now available of the orientation, location, and dynamics of α-tocopherol in lipid bilayers, there are still gaps in our knowledge of the effect of α-tocopherol and its potential receptors than control gene transcription. Read More

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September 2021

An overview of the fatty acid biosynthesis in the protozoan parasite Leishmania and its relevance as a drug target against leishmaniasis.

Mol Biochem Parasitol 2021 Sep 20:111416. Epub 2021 Sep 20.

Department of Biochemistry, University of Delhi South Campus, Benito Juarez Road, New Delhi, 110021, India. Electronic address:

Leishmaniasis is one of the fast-growing parasitic diseases worldwide. The treatment of this fatal disease presents a daunting challenge because of its adverse effects, necessity for long-term treatment regime, unavailability of functional drugs, emergence of drug resistance and the related expenditure. This calls for an urgent need for novel drugs and the evaluation of new targets. Read More

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September 2021

Hydrophobic and electrostatic interactions modulate protein escape at the ribosomal exit tunnel.

Biophys J 2021 Sep 20. Epub 2021 Sep 20.

Institute of Physics, Vietnam Academy of Science and Technology, 10 Dao Tan, Ba Dinh, Hanoi 11108, Vietnam; Graduate University of Science and Technology, Vietnam Academy of Science and Technology, 18 Hoang Quoc Viet, Cau Giay, Hanoi 11307, Vietnam. Electronic address:

After translation, nascent proteins must escape the ribosomal exit tunnel to attain complete folding to their native states. This escape process also frees up the ribosome tunnel for a new translation job. In this study, we investigate the impacts of energetic interactions between the ribosomal exit tunnel and nascent proteins on the protein escape process by molecular dynamics simulations using partially coarse-grained models which incorporate hydrophobic and electrostatic interactions of the ribosome tunnel of H. Read More

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September 2021

Targeted Free Energy Perturbation Revisited: Accurate Free Energies from Mapped Reference Potentials.

J Phys Chem Lett 2021 Sep 23:9449-9454. Epub 2021 Sep 23.

Atomistic Simulations, Italian Institute of Technology, Via Morego 30, Genova 16163, Italy.

We present an approach that extends the theory of targeted free energy perturbation (TFEP) to calculate free energy differences and free energy surfaces at an accurate quantum mechanical level of theory from a cheaper reference potential. The convergence is accelerated by a mapping function that increases the overlap between the target and the reference distributions. Building on recent work, we show that this map can be learned with a normalizing flow neural network, without requiring simulations with the expensive target potential but only a small number of single-point calculations, and, crucially, avoiding the systematic error that was found previously. Read More

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September 2021

Unusual Melting Trend in an Alkali Asymmetric Sulfonamide Salt Series: Single-Crystal Analysis and Modeling.

Inorg Chem 2021 Sep 23. Epub 2021 Sep 23.

Department of Chemistry and Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohio 43210, United States.

Developing low-melting alkali salts is of interest for both battery electrolytes and inorganic ionic liquids. In this study, we report a series of asymmetric alkali-metal sulfonamide salts based upon the (3-methoxypropyl)((trifluoromethyl)sulfonyl)amide (MPSA) anion. This family of salts features an unusual melting point trend, where the melting point of the salts decreases as the cation increases in size from Li to K but then the melting point as the cation further increases in size from K to Cs. Read More

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September 2021

Rotation in an Enantiospecific Self-Assembled Array of Molecular Raffle Wheels.

Angew Chem Int Ed Engl 2021 Sep 23. Epub 2021 Sep 23.

Technical University Munich, Physics Department E20, James-Franck Strasse 1, D-85748, Garching, GERMANY.

Tailored nano-spaces can control enantioselective adsorption and molecular motion. We report on the spontaneous assembly of a dynamic one-component system - a rigid kagome network with each pore occupied by a guest molecule - employing solely 2,6-bis(1H-pyrazol-1-yl)pyridine-4-carboxylic acid on Ag(111). The network cavity snugly hosts the guest, bestows enantiomorphic adsorption and allows selective rotational motions. Read More

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September 2021

Axonal growth on surfaces with periodic geometrical patterns.

PLoS One 2021 23;16(9):e0257659. Epub 2021 Sep 23.

Department of Physics and Astronomy, Tufts University, Medford, Massachusetts, United States of America.

The formation of neuron networks is a complex phenomenon of fundamental importance for understanding the development of the nervous system, and for creating novel bioinspired materials for tissue engineering and neuronal repair. The basic process underlying the network formation is axonal growth, a process involving the extension of axons from the cell body towards target neurons. Axonal growth is guided by environmental stimuli that include intercellular interactions, biochemical cues, and the mechanical and geometrical features of the growth substrate. Read More

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September 2021

Neighbor-enhanced diffusivity in dense, cohesive cell populations.

PLoS Comput Biol 2021 Sep 23;17(9):e1009447. Epub 2021 Sep 23.

Department of Physics, Korea University, Seoul, Korea.

The dispersal or mixing of cells within cellular tissue is a crucial property for diverse biological processes, ranging from morphogenesis, immune action, to tumor metastasis. With the phenomenon of 'contact inhibition of locomotion,' it is puzzling how cells achieve such processes within a densely packed cohesive population. Here we demonstrate that a proper degree of cell-cell adhesiveness can, intriguingly, enhance the super-diffusive nature of individual cells. Read More

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September 2021

The impact of different arrangement of molecular chains in term of low and high shear rate's viscosities on heat and mass flow of Non-Newtonian shear thinning fluids.

Comb Chem High Throughput Screen 2021 Jul 18. Epub 2021 Jul 18.

Engineer Abdullah Bugshan Research Chair for Dental and Oral Rehabilitation, College of Dentistry, King Saud University, Riyadh 11545, Saudi Arabia.

Background: Non-Newtonian fluids, especially shear thinning fluids, have several applications in the polymer industry, food industry, and even in everyday life. The viscosity of shear thinning fluids is sometimes decreased by two or three orders of magnitude due to the alignment of the molecules in order when the shear rate is increased, and it cannot be ignored in the case of polymer processing and lubrication problems.

Objective: So, the effects of viscosities at a low and high shear rate on the heat and mass boundary layer flow of shear thinning fluid over moving belts is investigated in this study. Read More

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Photons and qubits get a better connection.

Authors:
Adam M Kaufman

Science 2021 Sep 23;373(6562):1436-1437. Epub 2021 Sep 23.

JILA/Department of Physics, University of Colorado, Boulder, CO 80309, USA.

[Figure: see text]. Read More

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September 2021

Cell-free chemoenzymatic starch synthesis from carbon dioxide.

Science 2021 Sep 23;373(6562):1523-1527. Epub 2021 Sep 23.

Department of Strategic and Integrative Research, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300308, China.

[Figure: see text]. Read More

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September 2021

Costs balloon for huge new U.S. physics project.

Authors:
Adrian Cho

Science 2021 Sep 23;373(6562):1424-1425. Epub 2021 Sep 23.

[Figure: see text]. Read More

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September 2021

Restored strange metal phase through suppression of charge density waves in underdoped YBaCuO.

Science 2021 Sep 23;373(6562):1506-1510. Epub 2021 Sep 23.

Quantum Device Physics Laboratory, Department of Microtechnology and Nanoscience, Chalmers University of Technology, SE-41296 Göteborg, Sweden.

[Figure: see text]. Read More

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September 2021

Topological insulator vertical-cavity laser array.

Science 2021 Sep 23;373(6562):1514-1517. Epub 2021 Sep 23.

Technische Physik, Wilhelm-Conrad-Röntgen-Research Center for Complex Material Systems, and Würzburg-Dresden Cluster of Excellence ct.qmat, Universität Würzburg, Am Hubland, D-97074 Würzburg, Germany.

[Figure: see text]. Read More

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September 2021

pH-Dependent Interfacial Tension and Dilatational Modulus Synergism of Oil-Soluble Fatty Acid and Water-Soluble Cationic Surfactants at the Oil/Water Interface.

Langmuir 2021 Sep 23. Epub 2021 Sep 23.

Center for Complex Fluids Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213, United States.

While the concept of interfacial tension synergism in surfactant mixtures is well established, little attention has been paid to the possibility of synergistic effects on the interfacial rheology of mixed surfactant systems. Furthermore, interfacial tension synergism is most often investigated for mixtures of surfactants residing in a single phase. Here, we define dilatational modulus synergism and report a study of interfacial tension isotherms and complex dilatational moduli for a binary surfactant system with the two surfactants accessing the oil/water interface from opposite sides. Read More

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September 2021