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A quiz concerning the National Eligibility cum Entrance Test (NEET) 2024 exam features questions about chemistry concepts, including bonding in molecules, solubility, hydride boiling points, and reaction mechanisms.

The article presents a quiz on various chemistry topics, including questions on amines, organic compounds, hybridization, and oxidation numbers.

The article reports on the publication of a paper co-authored by the late Francis Crick in the early 1960s that tackles the subject of allostery, which is a vital biochemical process. Crick's co-author was Jeffries Wyman. It claims that Crick also studied the chemical structure of the DNA molecule with James Watson in the early 1950s.

A recent study conducted by researchers at the University of Medicine and Pharmacy "Iuliu Hatieganu" in Cluj Napoca, Romania, explored the effects of tomato extracts on colorectal cancer cells. The study aimed to determine the antiproliferative effect of the extracts and their influence on the secretion of growth factors involved in tumor neoangiogenesis. The results showed that the tomato extracts reduced the growth of malignant cells by hindering tumor neovascularization, suggesting potential therapeutic applications. This research provides valuable insights into the potential benefits of tomato extracts in the treatment of colon cancer. [Extracted from the article]

Insilico Medicine and its collaborators have published a study in Nature Biotechnology detailing the journey of their lead therapeutic program, which utilizes generative AI to discover a novel molecule and target for drug development. The study provides experimental data and evaluation of the TNIK inhibitor, highlighting the potential of AI-driven drug discovery to streamline and accelerate the process. The researchers trained their AI platform on datasets related to tissue fibrosis and used generative chemistry algorithms to design the lead molecule, INS018_055. Preclinical and clinical studies have shown promising results, and Phase 2 clinical trials are currently underway for the treatment of idiopathic pulmonary fibrosis (IPF). This research demonstrates the potential of AI in revolutionizing the field of drug discovery. [Extracted from the article]

The October 2014 issue of Pure and Applied Chemistry includes several papers arising from an IUPAC project on immunochemistry that describe interactions between molecules of the immune system and their ligands [1,2] and consider how a knowledge of this chemistry is furthering the development of both the analytical applications of immune-based sensors [3], and of better therapies for a variety of human medical conditions [4]. Each paper is structured to provide some historical context, followed by a critical presentation of our current perspective on the role chemistry is playing in the basic understanding of the immune system and its potential for exploitation. [ABSTRACT FROM AUTHOR]

Researchers from Penn State and the University of Nebraska-Lincoln have developed an ultrathin optical element using metamaterials that can control the direction of polarized electromagnetic light waves. This breakthrough allows for the identification and sorting of molecules based on their chirality or handedness, which can provide critical information about how they will interact with other systems. The optical element can quickly image the molecular structure of pharmaceuticals, aiding in the understanding of drug behavior. It can also be used to create right- or left-handed electromagnetic waves for classical and quantum communication systems. [Extracted from the article]

Pulsation is a universal phenomenon in all disciplines of nonlinear science, which generally exhibit various nonlinear soliton dynamic modes in nonlinear optics. With the emergence of real-time spectral measurement technology, a new phenomenon of optical soliton pulsation, "invisible" soliton pulsation, has gradually attracted researchers' attention. In this paper, by solving the coupled Ginzburg–Landau equation, we have discovered the partially "invisible" pulsation phenomenon of asymmetric soliton molecules (SMs) composed of two unequal-intensity pulses in a normal-dispersion Mamyshev oscillator for the first time. It is indicated that the fluctuation periods of each internal pulse in asymmetric SMs in terms of peak power, energy, and relative phase difference are all four roundtrips. However, the oscillation period of asymmetric SMs energy is two roundtrips, only half of the above period. Further research shows that the oscillation of the relative phase difference between two internal pulses in SMs is related to the variation of their intensity difference, which can also affect the position change of the spectral modulation peak. This work will enrich the research on "invisible" soliton pulsation and is of great significance for promoting the development of nonlinear dissipative systems. • We studied the pulsating dynamics of soliton molecules in a Mamyshev oscillator. • We discovered the partially "invisible" pulsation of asymmetric soliton molecules. • The total energy period of asymmetric soliton molecules is half of each inside pulse. • The "invisible" pulsation is caused by the intensity difference of the inside pulses. [ABSTRACT FROM AUTHOR]

A quiz concerning the fundamentals of chemistry covered in a June 2024 issue includes topics on molecular mass calculations, limiting reagents, and chemical laws' application.

Using a knowledge graph which is populated with all known molecules, input molecules are analyzed according to various similarity indexes which relate the input molecules to target proteins or other biological entities. The system of claim 1, wherein the report comprises molecule hypotheses surrounding the potential uses of the one or more received molecules. The method of claim 11, wherein the report comprises molecule hypotheses surrounding the potential uses of the one or more received molecules. [Extracted from the article]

A team of researchers from the University of Cambridge and the Max Planck Institute for Polymer Research in Germany have discovered that water molecules at the surface of salt water are organized differently than previously believed. This finding contradicts traditional textbook models and has implications for atmospheric chemistry and climate science. The researchers used a technique called heterodyne-detected vibrational sum-frequency generation (HD-VSFG) to study electrolyte solutions and developed computer models to simulate different scenarios. The results showed that both positively and negatively charged ions are depleted from the water/air interface, reversing previous models that suggested ions form an electrical double layer and orient water molecules in only one direction. This research has the potential to improve atmospheric chemistry models and other applications. [Extracted from the article]

The article focuses on the fundamental principles and techniques in organic chemistry, starting with the historical division of compounds into organic and inorganic categories. Topics discussed include the tetravalence of carbon and shapes of organic compounds, structural representations (complete, condensed, and bond-line), three-dimensional representations, classification of organic compounds, and nomenclature using both trivial and IUPAC systems.

Abstract: Despite the tremendous advances made by the ab initio theory of electronic structure of atoms and molecules, its applications are still not possible for very large systems. Therefore, semi-empirical model Hamiltonians based on the zero-differential overlap (ZDO) approach such as the Pariser–Parr–Pople, CNDO, INDO, etc. provide attractive, and computationally tractable, alternatives to the ab initio treatment of large systems. In this paper we describe a Fortran 90 computer program developed by us, that uses CNDO/2 and INDO methods to solve Hartree–Fock (HF) equation for molecular systems. The INDO method can be used for the molecules containing the first-row atoms, while the CNDO/2 method is applicable to those containing both the first-, and the second-row, atoms. We have paid particular attention to computational efficiency while developing the code, and, therefore, it allows us to perform calculations on large molecules such as C60 on small computers within a matter of seconds. Besides being able to compute the molecular orbitals and total energies, our code is also able to compute properties such as the electric dipole moment, Mulliken population analysis, and linear optical absorption spectrum of the system. We also demonstrate how the program can be used to compute the total energy per unit cell of a polymer. The applications presented in this paper include small organic and inorganic molecules, fullerene C60, and model polymeric systems, viz., chains containing alternating boron and nitrogen atoms (BN chain), and carbon atoms (C chain). [Copyright &y& Elsevier]

Presents an interview with theoretical physicist Steen Rasmussen regarding his desire and efforts to create artificial life. Impact of the papers about the creation of life made by physical chemist Ilya Prigogine and biophysicist Manfred Eigen on his interest in artificial life; Parts of an artificial organism such as a DNA-like molecule; Details of the creation of his protocells.

This study is a sequel of Part I of this paper [On AFS Algebra Part 1, submitted to Information Sciences]. In this paper, we will further study the properties and structures of sub-algebra of El algebra and EIn algebra. [ABSTRACT FROM AUTHOR]

In this paper we present the new version of the SCELib program (CPC Catalogue identifier ADMG) a full numerical implementation of the Single Center Expansion (SCE) method. The physics involved is that of producing the SCE description of molecular electronic densities, of molecular electrostatic potentials and of molecular perturbed potentials due to a point negative or positive charge. This new revision of the program has been optimized to run in serial as well as in parallel execution mode, to support a larger set of molecular symmetries and to permit the restart of long-lasting calculations. To measure the performance of this new release, a comparative study has been carried out on the most powerful computing architectures in serial and parallel runs. The results of the calculations reported in this paper refer to real cases medium to large molecular systems and they are reported in full details to benchmark at best the parallel architectures the new SCELib code will run on.Program summary: Title of program: SCELib2Catalogue identifier: ADGUProgram summary URL: Program obtainable from: CPC Program Library, Queen''s University of Belfast, N. IrelandReference to previous versions: Comput. Phys. Commun. 128 (2) (2000) 139 (CPC catalogue identifier: ADMG)Does the new version supersede the original program?: YesComputer for which the program is designed and others on which it has been tested: HP ES45 and rx2600, SUN ES4500, IBM SP and any single CPU workstation based on Alpha, SPARC, POWER, Itanium2 and X86 processorsInstallations: CASPUR, localOperating systems under which the program has been tested: HP Tru64 V5.X, SUNOS V5.8, IBM AIX V5.X, Linux RedHat V8.0Programming language used: CMemory required to execute with typical data: 10 Mwords. Up to 2000 Mwords depending on the molecular system and runtime parametersNo. of bits in a word: 64No. of processors used: 1 to 32Has the code been vectorized or parallelized?: YesNo. of bytes in distributed program, including test data, etc.: 3 798 507No. of lines in distributed program, including test data, etc.: 187 226Distribution format: tar.gzNature of physical problem: In this set of codes an efficient procedure is implemented to describe the wavefunction and related molecular properties of a polyatomic molecular system within the Single Center of Expansion (SCE) approximation. The resulting SCE wavefunction, electron density, electrostatic and exchange/correlation potentials can then be used via a proper Application Programming Interface (API) to describe the target molecular system which can be employed in electron–molecule scattering calculations. The molecular properties expanded over a single center turn out to also be of more general application and some possible uses in quantum chemistry, biomodelling and drug design are also outlined.Method of solution: The polycentre Hartee–Fock solution for a molecule of arbitrary geometry, based on linear combination of Gaussian-Type Orbital (GTO), is expanded over a single center, typically the Center Of Mass (C.O.M.), by means of a Gauss–Legendre/Chebyschev quadrature over the θ,φ angular coordinates. The resulting SCE numerical wavefunction is then used to calculate the one-particle electron density, the electrostatic potential and two different models for the correlation/polarization potentials induced by the impinging electron, which have the correct asymptotic behaviour for the leading dipole molecular polarizabilities.Restrictions on the complexity of the problem: Depending on the molecular system under study and on the operating conditions the program may or may not fit into available RAM memory. In this case a feature of the program is to memory map a disk file in order to efficiently access the memory data through a disk device.Typical running time: The execution time strongly depends on the molecular target description and on the hardware/OS chosen, it is directly proportional to the (r,θ,φ) grid size and to the number of angular basis functions used. Thus, from the program printout of the main arrays memory occupancy, the user can approximately derive the expected computer time needed for a given calculation executed in serial mode. For parallel executions the overall efficiency must be further taken into account, and this depends on the no. of processors used as well as on the parallel architecture chosen, so a simple general law is at present not determinable.Unusual features of the program: The code has been engineered to use dynamical, runtime determined, global parameters with the aim to have all the data fitted in the RAM memory. Some unusual circumstances, e.g., when using large values of those parameters, may cause the program to run with unexpected performance reductions due to runtime bottlenecks like those caused by memory swap operations which strongly depend on the hardware used. In such cases, a parallel execution of the code is generally sufficient to fix the problem since the data size is partitioned over the available processors. When a suitable parallel system is not available for execution, a mechanism of memory mapped file can be used; with this option on, all the available memory will be used as a buffer for a disk file which contains the whole data set, thus having a better throughput with respect to the traditional swapping/paging of the Unix OS. [Copyright &y& Elsevier]

Researchers at the University of Illinois Urbana-Champaign and the University of Wisconsin-Madison have developed a new antifungal molecule that has the potential to effectively kill fungi without causing toxicity in human cells. The molecule, called AM-2-19, was created by modifying the structure of the existing antifungal drug Amphotericin B. The researchers discovered that Amphotericin B kills fungi by extracting ergosterol from fungal cells, and they used this knowledge to modify the drug and reduce its interaction with cholesterol, thereby reducing its toxicity. AM-2-19 has shown promising results in in vitro assays, cell cultures, and live mice, and it has entered Phase 1 clinical trials. [Extracted from the article]

The molecules of life have a strange asymmetry – and we finally have a grasp on why, finds Hayley Bennett [ABSTRACT FROM AUTHOR]

Keywords for this news article include: Nanjing University of Information Science and Technology (NUIST), Drug Molecules, Drug Development, Drugs and Therapies, Health and Medicine. Keywords: Drug Development; Drug Molecules; Drugs and Therapies; Health and Medicine EN Drug Development Drug Molecules Drugs and Therapies Health and Medicine 1021 1021 1 06/19/23 20230625 NES 230625 2023 JUN 23 (NewsRx) -- By a News Reporter-Staff News Editor at Medical Devices & Surgical Technology Week -- A new study on drug molecules is now available. [Extracted from the article]

Symmetry is a useful concept in physics and chemistry. It can be used to find out some simple properties of a molecule or simplify complex calculations. In this paper a simple vector algebraic method is described to determine all symmetry elements of an arbitrary molecule. To carry out the symmetry analysis, a program has been written, which is also capable of generating the framework group of the molecule, revealing the symmetry properties of normal modes of vibration and symmetrizing the structure. To demonstrate the capabilities of the program, it is compared to other common widely used stand-alone symmetry analyzer (SYMMOL, Symmetrizer) and molecular modeling (NWChem, ORCA, MRCC) software. SYVA can generate input files for molecular modeling programs, e.g. Gaussian, using precisely symmetrized molecular structures. Possible applications are also demonstrated by integrating SYVA with the GAMESS and MRCC software. Program summary Program Title: SYVA Program Files doi: http://dx.doi.org/10.17632/xd4g8hyjf2.1 Licensing provisions: GNU GPLv3 Nature of problem: Determination of molecular symmetry elements and symmetry related properties, such as symmetries of vibrational normal modes, framework group, etc. Solution method: Vector algebraic solution (reflections and rotations) for the generation of symmetry operations, symmetry elements and symmetrization, matrix representation theory for the symmetries of vibrational normal modes. Unusual features: The program can determine the framework group of molecules, the symmetries of vibrational normal modes and symmetrize the geometry. [ABSTRACT FROM AUTHOR]

"The cool scientific advance here is that we're able to prove that these redox polymers with chirality can be very good sensors and interact with their preferred enantiomers", Su said. Keywords: Beckman Institute for Advanced Science and Technology; Chemicals; Chirality; Electrochemicals; Emerging Technologies; Health and Medicine; Nanotechnology; Science And Technology; Supramolecular; Supramolecular Chirality EN Beckman Institute for Advanced Science and Technology Chemicals Chirality Electrochemicals Emerging Technologies Health and Medicine Nanotechnology Science And Technology Supramolecular Supramolecular Chirality 847 847 1 05/22/23 20230526 NES 230526 2023 MAY 26 (NewsRx) -- By a News Reporter-Staff News Editor at Drug Week -- Recognizing and separating enantiomers is a difficult task for chemical engineers - one might say it gives them a bit of a headache. Furthermore, the study shows for the first time a phenomenon referred to as supramolecular chirality, an intriguing feature in which the polymer displays more chirality than the redox-center building blocks themselves. [Extracted from the article]

The article explores the top ten emerging technologies of 2018. Topics discussed include augmented reality, electroceuticals, meat grown from stem cells, bots that argue and instruct, implantable drug-making cells, artificial intelligence for rapid molecular design, advanced diagnostics for precision medicine, gene drive that has safety features, finding toxins with plasmonics and algorithms for quantum computers.

Keywords: Elements; Gases; Hydrogen; Inorganic Chemicals; Molecular Science; Science EN Elements Gases Hydrogen Inorganic Chemicals Molecular Science Science 2023 FEB 11 (NewsRx) -- By a News Reporter-Staff News Editor at Medical Imaging Week -- New research on molecular science is the subject of a new report. Elements, Gases, Hydrogen, Inorganic Chemicals, Molecular Science, Science. [Extracted from the article]

The search for small violations of the validity of the symmetrization postulate and of the spin-statistics connection (SSC) has been addressed in the last four decades by experimental tests performed in different physical systems of identical fermions or bosons. In parallel and consequently, theories extending the quantum mechanics to a more general level have been proposed to explain such possible violations. In this paper, we present the most stringent test to a possible violation of the SSC under permutation of the bosonic 16O nuclei in the 12C16O2 molecule. An upper limit of 3.8 x 10-12 for an SSC-anomalous CO2 molecule is obtained using saturated-absorption cavity ring-down spectroscopy in the SSC-forbidden (00°1-00°0) R(25) rovibrational transition of 12C162 at a 4.25-µm wavelength. Quantum mechanics implications of this result are discussed in the frame of the q-mutator theory. Finally, the perspective of stringent experimental tests of the symmetrization postulate in molecules that contain three or more identical nuclei is discussed. [ABSTRACT FROM AUTHOR]

The article reports on discoveries in chemistry, focusing on newly-recognized processes in chemical reactions and discusses how the discoveries may fundamentally change chemistry applications such as drug development.

We study the positron-nitrogen-molecule scattering process under the rovibrational coupling method to include the effect of rotational and vibrational motion of the nuclei dynamically during the scattering process. Here we compute the angle integrated elastic and (state-to-state) rotational excitation, elastic and (state-to-state) vibrational (summed over rotational) excitation, and total (summed over rotational and vibrational) cross sections for the incident positron energy between 0.0 and 10 eV. However, in present paper we concentrate our discussion on the results in the lower-energy region, especially below 3.0 eV. To calculate the cross sections we use the model correlation polarization potential to include the distortion effect of the target electronic state in the presence of the positron. The calculated total cross sections are compared with the theoretical calculations and experimental results. The present theoretical results agree quite well with the recent theoretical and measured values. The vibrational and rotational elastic and excitation cross sections are also compared with the existing theoretical results. The state-to-state potential coupling and dynamical coupling effects on different cross sections are studied. [ABSTRACT FROM AUTHOR]

The article discusses a research paper on a molecular knot with eight crossings, which references a study by David Leigh et al., published in an issue of the "Science", and mentions the materials and method used in the study.

The article discusses a research paper on a way to control bacterial genes using electricity. It references a study by William Bentley et al., published in an issue of the "Nature Communications". It tackles the significance of the ability of custom-made microbes to sense the environment and make biological molecules, and the use of redox molecules in the study.

In this paper, we investigate an extended complex modified Korteweg–de Vries equation. On zero background, based on Darboux transformation, breather solutions, breather molecules, breather-soliton molecules and breather-positons for extended complex modified Korteweg–de Vries equation are obtained by module resonance, velocity resonance and degenerate Darboux transformation. On nonzero background, breather solutions and breather-positons for extended complex modified Korteweg–de Vries equation are generated through Darboux transformation and degenerate Darboux transformation, respectively. • We obtain the breather-positons of the extended complex modified KdV equation. • The breather-soliton molecules for the extended complex modified KdV equation on zero background are generated. • For the extended complex modified KdV equation, we get first-order breather solutions that periodically evolve along the x -axis and t -axis on nonzero background. [ABSTRACT FROM AUTHOR]

Scientists at The Hospital for Sick Children have discovered a molecule, LK-2, that could potentially protect neurons during stroke and prevent stroke-related brain damage. Glutamate, a neurotransmitter, is a major contributor to stroke-induced brain damage. Previous drugs targeting glutamate receptors have been ineffective, as they can cause serious side effects. However, the team found that glutamate can also activate acid-sensing ion channels (ASICs) in brain cells. By developing LK-2, which selectively blocks the glutamate binding site in ASICs, the team was able to prevent glutamate from overstimulating ASICs and reduce cell death. This research provides a new approach to protecting the brain from glutamate toxicity without interfering with regular brain functions. [Extracted from the article]

Researchers at the Istituto Italiano di Tecnologia (IIT) and the European Molecular Biology Laboratory (EMBL) have discovered how gene expression can be modulated using small molecules. This breakthrough could lead to the development of drugs that target genetic mutations or modifications that affect gene expression, potentially treating tumors or genetic diseases. The study focused on splicing, a process in which specific sequences of RNA are cut and pasted to create functional versions. The researchers have also filed a patent for chemical compounds that act as splicing modulators, with the goal of regulating the production of specific proteins associated with defective or mutated genes. [Extracted from the article]

A report from Yunnan University in Kunming, China discusses the challenges of recognizing and utilizing drug compound structures represented in two-dimensional vector graphics. The researchers propose a multi-stage cognitive neural network model called MMSSC-Net, which predicts molecular vector graphics more accurately. Experimental results show that MMSSC-Net outperforms current methods and achieves an accuracy rate of 75-94% in cognitive recognition. This research provides new ideas for drug information discovery and exploring the unknown chemical space. [Extracted from the article]

The advent of precise measurements of the CMB anisotropies has motivated correspondingly precise calculations of the cosmic recombination history. Cosmic recombination proceeds far out of equilibrium because of a "bottleneck" at the n = 2 level of hydrogen: atoms can only reach the ground state via slow processes--two-photon decay or Lyman-α resonance escape. However, even a small primordial abundance of molecules could have a large effect on the interline opacity in the recombination epoch and lead to an additional route for hydrogen recombination. Therefore, this paper computes the abundance of the H2 molecule during the cosmic recombination epoch. Hydrogen molecules in the ground electronic levels Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. can either form from the excited H2 electronic levels Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. and C¹Πu or through the charged particles Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. HeH+, and H-. We follow the transitions among all of these species, resolving the rotational and vibrational sublevels. Since the energies of the Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. (Lyman band) and (Werner band) transitions are near the Lyman-a energy, the distortion of the CMB spectrum caused by escaped H Lyman-line photons accelerates both the formation and the destruction of H2 due to this channel relative to the thermal rates. This causes the populations of H2 molecules in Due to image rights restrictions, multiple line equation(s) cannot be graphically displayed. energy levels to deviate from their thermal equilibrium abundances. We find that the resulting H2 abundance is 10-17 at z = 1200 and 10-13 at z = 800, which is too small to have any significant influence on the recombination history. [ABSTRACT FROM AUTHOR]

Abstract: Stochastic models are often used when modelling chemical species that have low numbers of molecules. However, as these models become large, it can become computationally expensive to simulate even a single realisation of the system since even efficient simulation techniques have a high computational cost. One possible technique to approximate the stochastic system is moment closure. The moment closure approximation is used to provide analytic approximations to non-linear stochastic models. Until now, this approximation has only been applied to models with polynomial rate laws. In this paper we extend the moment closure method to cover models with rational rate laws. [Copyright &y& Elsevier]

Abstract: Biochemical reaction networks are often described by deterministic models based on macroscopic rate equations. However, for small numbers of molecules, intrinsic noise can play a significant role and stochastic methods may thus be required. In this work, we analyze the differences and similarities between a class of macroscopic deterministic models and corresponding mesoscopic stochastic models. We derive expressions that provide a clear and intuitive view upon the behavior of the stochastic model. In particular, these expressions show the dependence of both the dynamics and the stationary distribution of the stochastic model on the number of molecules in the system. As expected, most properties of the stochastic model correspond well with those in the deterministic model if the number of molecules is large enough. However, for some properties, both models are inconsistent, even if the number of molecules in the stochastic model tends to infinity. Throughout this paper, we use a bistable autophosphorylation cycle as a running example. For such a bistable system, we give an explicit proof that the rate of convergence to the stationary distribution (or the second eigenvalue of the transition matrix) depends exponentially on the number of molecules. [ABSTRACT FROM AUTHOR]

Abstract: The current understanding of internuclear potential of diatomic molecules is limited to electronic states. In this paper, we point out that every electronic-state internuclear potential is actually accompanied by a fine structure, which characterizes the detailed internuclear potential for each vibrational substate belonging to the same electronic state. This fine structure, which governs the bond length, the force constant, the vibration frequency, and the quantum motion for each vibrational state, is obtained by extending Bohm’s quantum potential [Bohm D. A suggested interpretation of the quantum theory in terms of hidden variable. Phys Rev 1952;85:166–79] to complex domain. It is shown that the fine structure of the internuclear potential can be determined exactly by the vibrational wavefunctions so that its predictions about the internuclear forces (Part I) and the vibrational nuclear quantum motion (Part II) are fully consistent with the Max Born’s probability interpretation of the vibrational wavefunctions, and are in line with El Naschie’s E-infinity [El Naschie MS. A review of E-infinity theory and the mass spectrum of high energy particle physics. Chaos, Solitons & Fractals 2004;19:209–36; El Naschie MS. E-infinity theory – some recent results and new interpretations. Chaos, Solitons & Fractals 2006;29:845–53; El Naschie MS. The concepts of E-infinity. An elementary introduction to the Cantorian-fractal theory of quantum physics. Chaos, Solitons & Fractals 2004;22:495–511], Nottale’s scale relativity [Nottale L. Fractal space-time and microphysics: Towards a theory of scale relativity. Singapore: World Scientific; 1993], and Ord’s random walk [Ord G. Fractal space time and the statistical mechanics of random works. Chaos, Soiltons & Fractals 1996;7:821–43] approaches to quantum mechanics. [Copyright &y& Elsevier]

Abstract: In the first part of this paper, structure–odour relationships for sandalwood odourants were studied for a set of 158 compounds (75 inactive and 83 active). The first step in the study consists in an evaluation of empirical rules concerning structure–sandalwood odour relationships, by means of decision trees. The main structural elements responsible for other than sandalwood odours are defined from the empirical rules. A search for new variables was carried out to define the essential elements for the sandalwood odour. The rules used to discriminate between sandalwood and non-sandalwood molecules lead to 80% correct discrimination. In the second part, fuzzy logic has been used as a tool in structure–camphoraceous odour relationships. The database studied included 99 molecules. The rules used to discriminate between camphor and non-camphor are given by an expert. Such rules account for the shape and the size of the molecules. Their adjustment by means of genetic algorithms (GAs) lead to 84% correct discrimination between camphor and non-camphor molecules. [Copyright &y& Elsevier]

Abstract: A large quantity of small molecules may migrate into a network of long polymers, causing the network to swell, forming an aggregate known as a polymeric gel. This paper formulates a theory of the coupled mass transport and large deformation. The free energy of the gel results from two molecular processes: stretching the network and mixing the network with the small molecules. Both the small molecules and the long polymers are taken to be incompressible, a constraint that we enforce by using a Lagrange multiplier, which coincides with the osmosis pressure or the swelling stress. The gel can undergo large deformation of two modes. The first mode results from the fast process of local rearrangement of molecules, allowing the gel to change shape but not volume. The second mode results from the slow process of long-range migration of the small molecules, allowing the gel to change both shape and volume. We assume that the local rearrangement is instantaneous, and model the long-range migration by assuming that the small molecules diffuse inside the gel. The theory is illustrated with a layer of a gel constrained in its plane and subject to a weight in the normal direction. We also predict the scaling behavior of a gel under a conical indenter. [Copyright &y& Elsevier]

Trichuris, whipworm nematode infections are prevalent in humans, domestic livestock and mammals. All share an epithelial dwelling niche and similar life cycle with the chronic infections that follow implying that immune evasion mechanisms are operating. Nematode excretory secretory (ES) products have been shown to be a rich source of immunomodulatory molecules for many species. The Trichuris muris model is a natural parasite of mice and has been used extensively to study host–parasite interactions and provides a tractable platform for investigation of the immunoregulatory capacity of whipworm ES. The present review details progress in identification of the composition of T. muris ES, immunomodulatory components and their potential mechanisms of action. The adult T. muris secretome is dominated by one protein with modulatory capacity although remains to be completely characterized. In addition, the secretome contains multiple other proteins and small molecules that have immunomodulatory potential, certainly by comparison to other Trichuris species. Moreover, T. muris-derived exosomes/exosome-like vesicles contain both protein and multiple miRNAs providing an alternate delivery process for molecules with the potential to modulate host immunity. [ABSTRACT FROM AUTHOR]

As we come to understand the secrets of iridescence in nature, we can harness this colourful phenomenon for a more sustainable future, finds Michael Allen [ABSTRACT FROM AUTHOR]

In reply to the Comment of Green et al. [Phys. Rev. A 95, 036701 (2017).] on our paper [Phys. Rev. A 94, 052709 (2016)], we reconfirm that all the conclusions are based on the observation and the comparisons of the theoretical and experimental data. One criticism of Green et al. [Phys. Rev. A 95, 036701 (2017).] concerns the positrophilic electrons and the inner valence electrons. The inner valence electrons or positrophilic electrons show most agreeable widths with the corresponding experimental measurements due to their narrowest momentum distributions for all 59 molecules. However, we agree with the criticism of Green et al. [Phys. Rev. A 95, 036701 (2017).] and reconfirm that this agreement does not represent the dominance of the inner valence in the annihilation process. In this Reply, we will clarify the difference between agreement and dominance and illustrate with some figures. Another criticism is about the approximation used in our paper. We emphasize that the averaged discrepancy of 34.2% for these molecules of the theoretical γ-ray spectra from the experimental measurements is due to the neglect of the positron-electron correlations, vibrational couplings, virtual-state formation, even tunneling of core electrons not the neglect of the positron wave function. In this Reply, we will show, even in this zero-order approximation, these positron-induced effects in the electron-positron annihilation process of molecules can also be analyzed with more corrections and explanations. [ABSTRACT FROM AUTHOR]

In this paper, a reduced (3+1)-dimensional nonlinear wave equation describing the dynamic of liquid with gas bubble, namely Kudryashov-Sinelshchikov (KS) equation is carefully investigated. After applying the simplified linear superposition principle (LSP) and the velocity resonance (VR) the fact that there has no existence of soliton molecule to KS equation is formally proofed. Simultaneously, two new resonant multi-soliton solutions constructed with distinct physical structures are also generated. Comparing with the existing ones our solutions are much more general. Most of all, their formula forms reveal the influences of the arbitrary coefficients of the bubble-liquid-dispersion, the y-transverse-perturbation and the z-transverse-perturbation to the traveling soliton waves. Finally, the propagations of inelastic interactions of resonant two-soliton waves are shown in Figures 1-6. Particularly, by specifying special values to the resonant multi-soliton solution gives three-bound-soliton waves moving with the same speed and direction which is in the manner similar to the property of soliton molecule, as shown in Figure 6. The extracted results not only show the efficiency of the simplified LSP but also have potential applications to the physical phenomena of soliton molecules and the resonance of multi-soliton waves. [ABSTRACT FROM AUTHOR]

• In virtue of the simple Hirota bilinear method, the multiple soliton solutions of the (2 + 1)–dimensional Sawada–Kortera (2DSK) equation are presented. Furthermore, we have found that the multiple soliton solutions possess other types of forms that different formally but equivalent actually. • By means of the multiple solitons and a subtle velocity resonance ansatz excited by an observation of bound state behavior of solitons, we derive some soliton molecules (SMs) and asymmetric solitons of the 2DSK equation. • By dealing with partial parameters under the velocity resonance and module resonance mechanisms along with complex conjugate condition assumptions, abundant new interaction structures including soliton molecules (SMs), breather molecules (BMs) and/or soliton-breather molecules (SBMs) of the 2DSK are given. Besides, theoretical analysis for the interaction structures such as the motion trajectories of the breather and/or soliton molecules are unearthed and reported firstly in this paper. Soliton molecules may exist experimentally and theoretically. In this work, we generate some soliton molecules for (2 + 1)–dimensional Sawada–Kotera equation by multiple soliton solutions and a subtle velocity resonance ansatz excited by an observation of bound state behavior of solitons. Asymmetric solitons can be derived by selecting specific parameters of soliton molecules. On the basis of multiple soliton solutions, some new interaction structures consisting of soliton molecules (SMs), breather molecules (BMs) and/or soliton-breather molecules (SBMs) are found by dealing with partial parameters under the velocity resonance and module resonance mechanisms along with complex conjugate condition assumptions. Abundant results show excellent performances and make the problem integrated solving approach a promising one. [ABSTRACT FROM AUTHOR]