Identical Constituents Research Articles

Two-Dimensional Correlation Spectroscopy (2D-COS) Analysis of Evolving Hyperspectral Images.

The evolutionary behavior is examined for heterogeneously distributed hyperspectral images of a simulated biological tissue sample comprising lipid-like and protein-like components during the aging process. Taking a simple planar average of a spectral image loses useful information about the spatially resolved nature of the data. In contrast, multivariate curve resolution (MCR) analysis of a spectral image at a given stage of aging produces a set of loadings of major component groups. Each loading represents the combined spectral contributions of a mixture of similar but not identical constituents (i.e., lipid-like and protein-like components). Temporal analysis of individual component groups using two-dimensional correlation spectroscopy (2D-COS) and MCR provides much-streamlined results without interferences from the overlapped contributions. Grouping of data into separate components also allows for the effective comparison of the parallel processes of lipid oxidation and protein denaturation involving a number of constituents using the heterocomponent 2D-COS analysis. The complex interplays of lipid constituents and protein secondary structures during the tissue aging process are unambiguously highlighted. The possibility of extending this approach to a much more general form of applications using a moving window analysis is also discussed.

Generating indistinguishability within identical particle systems: spatial deformations as quantum resource activators.

Identical quantum subsystems can possess a property which does not have any classical counterpart: indistinguishability. As a long-debated phenomenon, identical particles' indistinguishability has been shown to be at the heart of various fundamental physical results. When concerned with the spatial degree of freedom, identical constituents can be made indistinguishable by overlapping their spatial wave functions via appropriately defined spatial deformations. By the laws of quantum mechanics, any measurement designed to resolve a quantity which depends on the spatial degree of freedom only and performed on the regions of overlap is not able to assign the measured outcome to one specific particle within the system. The result is an entangled state where the measured property is shared between the identical constituents. In this work, we present a coherent formalization of the concept of deformation in a general [Formula: see text]-particle scenario, together with a suitable measure of the degree of indistinguishability. We highlight the basic differences with non-identical particles scenarios and discuss the inherent role of spatial deformations as entanglement activators within the spatially localized operations and classical communication operational framework. This article is part of the theme issue 'Identity, individuality and indistinguishability in physics and mathematics'.

Quantum Central Limit Theorems, Emergence of Classicality and Time-Dependent Differential Entropy.

We derive some quantum central limit theorems for the expectation values of macroscopically coarse-grained observables, which are functions of coarse-grained Hermitian operators consisting of non-commuting variables. Thanks to the Hermiticity constraints, we obtain positive-definite distributions for the expectation values of observables. These probability distributions open some pathway for the emergence of classical behaviours in the limit of an infinitely large number of identical and non-interacting quantum constituents. This is in contradistinction to other mechanisms of classicality emergence due to environmental decoherence and consistent histories. The probability distributions thus derived also enable us to evaluate the non-trivial time-dependence of certain differential entropies.

Many-body coherence and entanglement probed by randomized correlation measurements

We show how coherences between identical constituents of a many-body quantum state can be interrogated by suitable correlation functions, and identify sufficient conditions under which low-order correlators fully characterize many-body coherences, as controlled by the constituents' mutual distinguishability. Comparison of correlators of different order detects many-body entanglement.

Using Metabolite Data to Develop Patient Centric Specification for Amide Impurity in Vildagliptin Tablets

Many specified impurities in vildagliptin’s finished product have been disclosed in the literature that are above their qualification threshold. We used the impurity B (amide impurity) as a case example to explore whether existing literature can be leveraged to determine the safe level of impurity and thereby develop a patient-centric specification (PCS) for impurities. No-observed-adverse-effect level (NOAEL) was derived from rate metabolism information and converted to human equivalent dose (HED). The HED was estimated as 6.5 mg/day. The high qualification levels are supported by repeat dose toxicity studies performed in rats, mice and dogs. Maximum theoretical amount (MTA) was correlated with the maximum observed amount (MOA) to verify whether the exposure was due to impurity and/or metabolite. MOA/MTA was found ≥1 suggesting that metabolism contributed to the amount excreted in feces and therefore could be used to further justify a higher specification limit than the usual one of ≤0.5%. Quite often the drug metabolism and degradation pathways overlap, resulting in the formation of identical constituents. Therefore, metabolism data can be leveraged for deriving safe levels of degradation impurities and develop PCS for impurities.

Toward an accommodation account of deaccenting under nonidentity

Two competing models attempt to explain the deaccentuation of antecedent-nonidentical discourse-inferable material (e.g., Bach wrote many pieces for viola. He must have LOVED string instruments). One uses a single grammatical constraint to license deaccenting for identical and nonidentical material. The second licenses deaccenting grammatically only for identical constituents, whereas deaccented nonidentical material requires accommodation of an alternative antecedent. In three experiments, we tested listeners’ preferences for accentuation or deaccentuation on nonidentical inferable material in out-of-the-blue contexts, supportive discourse contexts, and in the presence of the presupposition trigger too. The results indicate that listeners by default prefer for inferable material to be accented, but that this preference can be mitigated or even reversed with the help of manipulations in the broader discourse context. By contrast, listeners reliably preferred for repeated material to be deaccented. We argue that these results are more compatible with the accommodation model of deaccenting licensing, which allows for differential licensing of deaccentuation on inferable versus repeated constituents and provides a principled account of the sensitivity of accentuation preferences on inferable material to broader contextual manipulations.

What information can be obtained from the tears of a patient with primary open angle glaucoma?

Since tears are a biological fluid, they have a potential diagnostic value for ophthalmic diseases. The aim of this study was to compare tear supernatants and pellets obtained from patients suffering from primary open angle glaucoma (POAG) and healthy persons (HPs) using transmission electron microscopy (TEM) and molecular biological methods.Tear supernatants and pellets were prepared using ultrafiltration and ultracentrifugation and were examined by negative staining and immunogold labelling TEM. DNA of the pellets was isolated, quantified and sequenced using a MiSeq (Illumina, USA) genomic sequencer with the Reagent Kit v3 (600 cycles, Illumina, USA). MicroRNA was isolated and quantified from the pellets; miR-146b, miR-16 and miR-126 were detected using TaqMan MicroRNA Assays (Applied Biosystems, USA).TEM of tear supernatants from both POAG patients and HPs revealed identical constituents: spherical or cup-shaped vesicles, “non-vesicles”, cell debris and macromolecular aggregates. Pellets of POAG patients and HPs contained small extracellular vesicles (sEVs) non-labelled vesicles and “non-vesicles”; pellets of sick persons also contained sEVs with “a capsule”. POAG-patient tear pellets showed elevated concentrations of genomic ds-DNA and SINE-repeats, and different expressions of miR-146b, miR-16 and miR-126 and a different set of bacterial DNA in comparison with pellets obtained from the tears of HPs.The data obtained indicate that the tears of HPs and POAG patients could serve as an object for TEM studies and as a source of sEV-containing preparations (pellets), which, in turn, could be used for the isolation and study of genomic ds-DNA and RNA. Our data provide the basis for using tears for diagnostic applications.

Nanocellulose incorporated graphene/polypyrrole film with a sandwich-like architecture for preparing flexible supercapacitor electrodes

A novel and well-designed film was prepared from cellulose nanofibers (CNF), reduced graphene oxide (RGO) and polypyrrole (PPy). It was fabricated through an altering vacuum filtration by combining the chemical reduction process. The obtained film displayed a sandwich-like structure and the bulk PPy was wrapped in RGO/CNF framework, resulting a free-standing and highly flexible supercapacitor electrode. The incorporation of hydrophilic CNF into film enhanced the diffusion paths for ions and electrons, and the excellent interactions between these three constituents achieved a synergistic effect on the structural integrity and electrochemical performance of the resultant film electrode. The specific capacitance of the sandwich-like film electrode was as high as 304 F g−1 and 81.8% capacitance was retained after 1000 charge/discharge cycles. This capacitance value was higher than those of individual RGO or PPy films and randomly mixed film with identical constituents. Besides, a solid state symmetric supercapacitor was assembled by two pieces of the resultant film electrodes and 1 M H2SO4-saturated CNF membrane as a polymer electrolyte separator. The device exhibited a high specific capacitance of 625.6 F g−1 at 0.22 A g−1, the capacitance retention of 75.4% after 5000 cycles, and a high energy density of 21.7 Wh kg−1 at the power density of 0.11 kW kg−1. These above results demonstrated that the presented sandwich-like film electrode was promising and alternative approach for the development of further portable energy storage devices with lightweight and flexible characteristics.

Robust Superlubricity of Gold–Graphite Heterointerfaces

AbstractNoncommensurate 2D interfaces hold great promise toward low friction and nanoelectromechanical applications. For identical constituents, the crystals interlock at specific rotational configurations leading to high barriers for slide. In contrast, nonidentical constituents comprising different lattice parameters should enable robust superlubricity for all rotational configurations. This is however not the case for gold–graphite interfaces, as both theory and experiments show scaling behavior of the sliding force as a function of the interface contact area. By simulating the sliding force for gold–graphite interfaces, this work shows that the origin for high force barriers at special angular configurations is a result of commensurability between the moiré structure and the contact geometry. Consequently, this paper suggests new geometries that can potentially overcome such commensurability effects to enable robust superlubricity.

Dopamine and serotonin contribute to Paecilomyceshepiali against chronic unpredictable mild stress induced depressive behavior in Sprague Dawley rats.

Paecilomyces hepiali contains identical chemical constituents to Cordycepssinensis, and it presents antidepressant‑like activity via regulating noradrenergic and dopaminergic systems. Behavioral despair depression models serve important roles in scientific screening and evaluation of antidepressants. The present study aims to investigate the antidepressant‑like activity of P. hepiali extract (PHC) in chronic unpredictable mild stress (CUMS)‑induced rat model of depression. Following four weeks of treatment, similar to fluoxetine at 3mg/kg (positive drug), PHC at doses from 0.08 to 2.0g/kg strongly increased sucrose preference and reduced the immobility time of depression‑like rats in forced swimming test. The hypo‑level of adrenocorticotropic hormone, noradrenaline and glucocorticoid receptor in serum and hypothalamus of depression‑like rats was enhanced by PHC. PHC normalized CUMS‑induced disorders of dihydroxyphenylacetic acid, dopamine, 5‑hydroxytryptamine (5‑HT) and 5‑hydroxyindoleacetic acid in serum and/or hypothalamus of depression‑like rats. Moreover, PHC enhanced the expression of tyrosine hydroxylase and reduced the levels of dopamine D2 receptor and 5‑HT2A receptor in hypothalamus. These results suggested that the antidepressant‑like effects of PHC in CUMS‑induced depression are associated with not only the modulation of dopamine, but also the regulation of 5-HT.

Tissue-based metabolite profiling and qualitative comparison of two species of Achyranthes roots by use of UHPLC-QTOF MS and laser micro-dissection

Achyranthes bidentata and Achyranthes aspera are saponin and steroid rich medicinal plants, used extensively for therapeutic treatments in Traditional Chinese Medicine (TCM) and Ayurveda. A. bidentata is reported to be one of the rare and extensively exploited medicinal plant species that face the issue of being endangered. Finding qualitative substitute with identical phyto-constituents contributing to similar composition and pharmacological benefits will help in reducing the burden of exploitation of the natural habitats of such plants. In the present study, a comparative metabolite analysis of the whole drug and specific tissues isolated by laser micro-dissection (LMD) was carried out for both the selected species, by use of ultra-high performance liquid chromatography-quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS). The results of the study indicate that the cortex and the medullary ray tissues are rich in their content of steroidal and saponin constituents such as (25S)-inokosterone-20,22-acetonide, ginsenoside Ro, bidentatoside II and achyranthoside B. Metabolite profiling of the whole tissues of both the species indicates presence of identical constituents. Thus, it is inferred that A. bidentata and A. aspera can be used as qualitative substitutes for each other.

Essential oils extracted from Phoebe hui Cheng ex Yang: Chemical constituents, antitumor and antibacterial activities, and potential use as a species identifier

The essential oils in Phoebe hui Cheng ex Yang were extracted from its roots, trunk, bark, branches, and leaves by a hydrothermal method and then analyzed by gas chromatography–mass spectrometry. The essential oils extracted from the xylem of the roots and trunks of this species had similar chemical constituents (primarily α-bergamotene, calarene, 3,7-guaiadiene, β-sesquiphellandrene, β-farnesene, β-bisabolene, torreyol, and τ-muurolol) in similar quantities. Meanwhile, the main chemical constituents of the essential oil extracted from the xylem of this species were considerably different from those extracted from Phoebe zhennan. Hence, analysis of the oils extracted from the xylem can be used to distinguish between these species. The essential oils extracted from the bark, branches, and leaves of P. hui Cheng ex Yang had identical chemical constituents. The bark oil comprised mainly cubebene, α-muurolene, δ-cadinene, cadina-1,4-diene, guaiol, δ-cadinol, and α-cadinol, whereas the branch oil mainly included cubebene, α-selinene, δ-cadinene, cadina-1,4-diene, guaiol, δ-cadinol, and α-cadinol. The leaf oil extract consisted of cyclosativene, γ-muurolene, β-selinene, α-selinene, γ-cadinene, δ-cadinene, δ-cadinol, γ-eudesmol, α-cadinol, β-eudesmol, and α-eudesmol. Although the antimicrobial effects of the essential oils extracted from the individual tree parts were unclear, a mixture of these oils exhibited significant antitumor properties.

Iron(ii) complexes of 2-mercaptopyridine as rubredoxin site analogues.

The synthesis, characterization and reactivity studies of iron(ii) complexes [FeII(PySH)4](OTf)2, 1-(OTf)2, [FeII(PySH)4](ClO)4, 1-(ClO4)2, and [FeII(PyS)2]n, (2), of a 2-mercaptopyridine (PySH) ligand are discussed. The X-ray crystal structures of both 1-(OTf)2 and 1-(ClO4)2 reveal a distorted tetrahedral geometry at the iron(ii) center with identical constituents. All the pyridine nitrogen atoms are protonated and thiolate ions are coordinated to the iron(ii) center. The structure and function of complex 1-(OTf)2 or 1-(ClO4)2 resembles the active site of rubredoxin. Complex 2 has octahedral geometry at the iron(ii) center forming a 1-D coordination polymer. Complex 1-(OTf)2 exhibits a high positive redox potential (E1/2 = 0.23 V vs. Ag/AgCl) which reduces to -0.12 V in the presence of triethylamine under an inert atmosphere. This change of the redox potential is highly reversible in the presence of a weak acid such as p-toluenesulfonic acid, pTsOH. DFT studies show that the complex cation [FeII(PySH)4]2+ upon treatment with a base converts to its anionic congener, [FeII(PyS)4]2-, via the deprotonation of the pyridinium moiety. The iron(ii) complexes readily react with molecular oxygen to yield the corresponding iron(iii) complex, which rapidly decays to form pyridine disulphide (Py2S2) and an iron(ii) complex.

Tetragonal versus Hexagonal: Structure-Dependent Catalytic Activity of Co/Zn Bimetallic Metal-Organic Frameworks.

Tetragonal and hexagonal phases of monometallic Zn and bimetallic Co/Zn metal-organic frameworks (MOFs), with secondary building units (SBUs) containing a M3O (M = metal) cluster, were synthesized from identical constituents using a benzenetricarboxylate (BTC(3-)) linker that forms decorated 3,6- and 3,5-connected networks, respectively. There exist subtle differences between the SBUs; one of the metal atoms in the M3O cluster in the tetragonal phase has one dissociable DMF solvent molecule while that in the hexagonal phase has three. Connectivities between the SBUs form one-dimensional channels in both MOFs. These MOFs catalyze the chemoselective addition of amines to epoxides, giving exclusively β-hydroxyamine under heterogeneous conditions. A ring-opening reaction of a symmetrical epoxide showed that the hexagonal phase diastereoselectively yields trans-alcohol, exhibiting an exquisite model for structure-dependent activity.

The odor of matcha (Japanese powdered green tea) as the base note of green tea leaves

We previously reported the group of aroma constituents that characterize the odor of sencha (green tea made from leaves) which is similar to but distinct from the odor of commercially available matcha (Japanese green tea made from powder).This study, investigated whether the group of aroma compounds contributing to this matcha-like odor is present in all green tea cultivars and products. Crude sencha teas made from the 'Yabukita', 'Sayamakaori', 'Samidori', and 'Ujimidori' cultivars, and teas prepared by different processes (hojicha and unkacha), were investigated. These green tea leaves had a common matcha-like odor originating from a group of identical constituents. Commercially available matcha were studied as the source of the standard odor. The extracts obtained from matcha were separated into groups with different odors by fractional distillation. Chemical and analytical methods showed that the group of key compounds producing the matcha-like odor included a minute quantity of several aliphatic aldehydes. Many aldehyde proton signals were observed by 1H NMR and some aldehydes were detected by mass spectroscopy. It was concluded that a matcha-like odor that contained some aliphatic aldehydes was the base note of green tea leaves, indicating the importance of the matcha-like odor to green tea's odor character.

Quantum Mechanics and the Principle of Maximal Variety

Quantum mechanics is derived from the principle that the universe contain as much variety as possible, in the sense of maximizing the distinctiveness of each subsystem. The quantum state of a microscopic system is defined to correspond to an ensemble of subsystems of the universe with identical constituents and similar preparations and environments. A new kind of interaction is posited amongst such similar subsystems which acts to increase their distinctiveness, by extremizing the variety. In the limit of large numbers of similar subsystems this interaction is shown to give rise to Bohm's quantum potential. As a result the probability distribution for the ensemble is governed by the Schroedinger equation. The measurement problem is naturally and simply solved. Microscopic systems appear statistical because they are members of large ensembles of similar systems which interact non-locally. Macroscopic systems are unique, and are not members of any ensembles of similar systems. Consequently their collective coordinates may evolve deterministically. This proposal could be tested by constructing quantum devices from entangled states of a modest number of quits which, by its combinatorial complexity, can be expected to have no natural copies.

Identification of Chinese Herbs Using a Sequencing-Free Nanostructured Electrochemical DNA Biosensor.

Due to the nearly identical phenotypes and chemical constituents, it is often very challenging to accurately differentiate diverse species of a Chinese herbal genus. Although technologies including DNA barcoding have been introduced to help address this problem, they are generally time-consuming and require expensive sequencing. Herein, we present a simple sequencing-free electrochemical biosensor, which enables easy differentiation between two closely related Fritillaria species. To improve its differentiation capability using trace amounts of DNA sample available from herbal extracts, a stepwise electrochemical deposition of reduced graphene oxide (RGO) and gold nanoparticles (AuNPs) was adopted to engineer a synergistic nanostructured sensing interface. By using such a nanofeatured electrochemical DNA (E-DNA) biosensor, two Chinese herbal species of Fritillaria (F. thunbergii and F. cirrhosa) were successfully discriminated at the DNA level, because a fragment of 16-mer sequence at the spacer region of the 5S-rRNA only exists in F. thunbergii. This E-DNA sensor was capable of identifying the target sequence in the range from 100 fM to 10 nM, and a detection limit as low as 11.7 fM (S/N = 3) was obtained. Importantly, this sensor was applied to detect the unique fragment of the PCR products amplified from F. thunbergii and F. cirrhosa, respectively. We anticipate that such a direct, sequencing-free sensing mode will ultimately pave the way towards a new generation of herb-identification strategies.

Metric of two balancing Kerr particles in physical parametrization

The present paper aims at elaborating a completely physical representation for the general 4-parameter family of the extended double-Kerr spacetimes describing two spinning sources in gravitational equilibrium. This involved problem is solved in a concise analytical form by using the individual Komar masses and angular momenta as arbitrary parameters, and the simplest equatorially symmetric specialization of the general expressions obtained by us yields the physical representation for the well-known Dietz-Hoenselaers superextreme case of two balancing identical Kerr constituents. The existence of the physically meaningful "black hole-superextreme object" equilibrium configurations permitted by the general solution may be considered as a clear indication that the spin-spin repulsion force might actually be by far stronger than expected earlier, when only the balance between two superextreme Kerr sources was thought possible. We also present the explicit analytical formulas relating the equilibrium states in the double-Kerr and double-Reissner-Nordstr\"om configurations.

Blind Multilinear Identification

We discuss a technique that allows blind recovery of signals or blind identification of mixtures in instances where such recovery or identification were previously thought to be impossible. These instances include: 1) closely located or highly correlated sources in antenna array processing; 2) highly correlated spreading codes in code division multiple access (CDMA) radio communication; and 3) nearly dependent spectra in fluorescence spectroscopy. These have important implications. In the case of antenna array processing, it allows for joint localization and extraction of multiple sources from the measurement of a noisy mixture recorded on multiple sensors in an entirely deterministic manner. In the case of CDMA, it allows the possibility of having a number of users larger than the spreading gain. In the case of fluorescence spectroscopy, it allows for detection of nearly identical chemical constituents. The proposed technique involves the solution of a bounded coherence low-rank multilinear approximation problem. We show that bounded coherence allows us to establish existence and uniqueness of the recovered solution. We will provide some statistical motivation for the approximation problem and discuss greedy approximation bounds. To provide the theoretical underpinnings for this technique, we develop a corresponding theory of sparse separable decompositions of functions, including notions of rank and nuclear norm that can be specialized to the usual ones for matrices and operators and also be applied to hypermatrices and tensors.

Charge Photogeneration in Donor–Acceptor Conjugated Materials: Influence of Excess Excitation Energy and Chain Length

We investigate the role of excess excitation energy on the nature of photoexcitations in donor-acceptor π-conjugated materials. We compare the polymer poly(2,6-(4,4-bis(2-ethylhexyl)-4H-cyclopenta[1,2-b;3,4-b']dithiophene)-4,7-benzo[2,1,3]thiadiazole) (PCPDTBT) and a short oligomer with identical constituents at different excitation wavelengths, from the near-infrared up to the ultraviolet spectral region. Ultrafast spectroscopic measurements clearly show an increased polaron pair yield for higher excess energies directly after photoexcitation when compared to the exciton population. This effect, already observable in the polymer, is even more pronounced for the shorter oligomer. Supported by quantum chemical simulations, we show that excitation in high-energy states generates electron and hole wave functions with reduced overlap, which likely act as precursors for the polaron pairs. Interestingly, in the oligomer we observe a lifetime of polaron pairs which is one order of magnitude longer. We suggest that this behavior results from the intermolecular nature of polaron pairs in oligomers. The study excludes the presence of carrier multiplication in these materials and highlights new aspects in the photophysics of donor-acceptor small molecules when compared to polymers. The former are identified as promising materials for efficient organic photovoltaics.