Bond Stretch Research Articles

Radical to non-radical conversion during PMS activation triggered by optimized electronic structure: Orientational regulation of oxidation pathway for water remediation

The orientational regulation of non-radical pathways is significant in the peroxymonosulfate (PMS)-based AOP for practical potential, but remains challenge. Here, the Se-doped Co(OH)2 hollow spheres (CoHS-Se-CR) were designed for PMS activation to rapidly degrade gatifloxacin (GAT) antibiotic, with over 95 % GAT removal in 20 min. DFT and experimental trials reveal the downshift of d-band center of Co 3d and O − H bond stretch in PMS via Se doping of Co(OH)2. The active HSO5•− generated via the breaking of O–H bond triggers the radical to the non-radical conversion of the degradation mechanism, dominated by 1O2 and assisted by electron transport process. Both oxygen vacancy and Se(Ⅵ) were involved in 1O2 generation and Co(III)/Co(II) cycle. The CoHS-Se-CR/PMS system showed high efficiency for GAT removal in a wide pH range and strong resistance to anionic interference. This work provides a new strategy for designing PMS activators to construct orientational non-radical AOP.

Photo-induced loss of H2 from H2S, CH4, H2O and SiH4, when and why is it possible

We have explored the possibility of forming H⋅ and H2 from H2S, CH4, H2O and SiH4 in a series of ab initio calculations. The key finding is that H2S can give rise to direct photolytic ultrafast formation of H2 This finding is in agreement with the available experimental data and is a result of a directed pathway that leads toward H2 formation at easily accessible wavelengths. It arises at the (conical) intersection between the two lowest-lying electronic states. This intersection is a result of the valence orbital interaction of the two hydrogen atoms. This interaction is becoming more favorable as the S-H bonds simultaneously becomes longer. The H-S σ-σ∗ bonding interaction cannot compete with the bond formation that takes place between the hydrogens as two bonds stretch simultaneously. For oxygen this interaction it predominant. The reason is that sulfur has a higher principal quantum number and the interaction with the 1s of hydrogen therefore is less favorable. The excited states that are involved in the H2 formation from H2S could be populated by, for example, a two-photon 400 nm excitation. The other hydrides have a more entangled potential energy landscape close to the Franck-Condon region in the direction of the reaction coordinate that leads to H2 loss and as a result the direct loss of a hydrogen atom is favored. A two-photon excitation could be induced by femtosecond laser pulses that at the same time is proposed as a future platform for sensing the H2S molecules with the backward transient absorption scheme. The implication would be that both sensing and photoinduced H2 formation could be in place at the same time which justifies the use of expensive femtosecond light sources getting “two for the price of one”.

Controlled Phonon Transport via Chemical Bond Stretching and Defect Engineering: The Case Study of Filled β-Mn-Type Phases.

Controlling the elastic properties of the material could become a powerful tool for tuning the thermal transport in solids. Nevertheless, the impact of the crystal structure, chemical bonding, and elastic properties on the lattice thermal conductivity remains to be elucidated. This is a pivotal issue for the advancement of thermoelectric (TE) materials. In this context, the influence of cation substitution in tetrahedral voids on the structural, thermal, and TE properties of α- and β-PbyGa6-xInxTe10─filled β-Mn-type phases─is reported here. The investigated materials show semiconducting behavior and a change from p- to n-type conductivity, depending on the chemical composition and temperature. Our findings indicate that the electronic transport in β-Mn-type phases is largely influenced by the substantial distortion of the Te framework, which causes the low weighted mobility and strong scattering of charge carriers. The presence of a significant anharmonicity of lattice vibrations results in the ultralow lattice thermal conductivity of PbyGa6-xInxTe10 materials. With increasing x, κL decreases from 0.59 to an extremely low value of 0.36 W m-1 K-1 at 298 K due to the decrease of bonding energy, intensification of anharmonic thermal vibrations of atoms, and formation of point defects. This work demonstrates the efficacy of utilizing the crystal structure and elastic properties to regulate phonon transport in functional materials.

Characterization of Silver Nanoparticles Synthesized With Fungi Isolated From Cocoa and Orange Plantation Soils

Green synthesis of nanoparticles with various metals is being interested among researchers globally attention for due to their safety, environmental friendliness and non-toxicity in contrast to chemical synthesis. Here, fungi were isolated from rhizosphere of cocoa and orange obtained from Federal University of Technology, Akure using standard mycological techniques with the aim of synthesizing silver nanoparticles. The silver nanoparticles synthesized by these fungal isolates were characterized using Ultraviolet-Visible (UV-Vis) and Fourier Transmission Infra- Red (FTIR) spectroscopy. Seven fungi isolated from the soil samples viz. Nigrospora sphaerica, Penicillium discolor, P. digitatum, Neurospora crassa, Alternarium infectoria, Trichophyton verrucosum and Mucor mucedo. The colour transformation from yellow to brown indicated the formation of silver nanoparticles. All the isolates showed an intense peak in the wavelength range of 410-440 nm. The FTIR analysis of silver nanoparticles synthesized by N. sphaerica, P. discolor, P. digitatum, N. crassa, A. infectoria, T. verrucosum and M. mucedo revealed the existence of a band at different stretches of bonds at different peaks of 3314.36 cm-1, 3310.47 cm-1, 2412.22 cm-1, 3912.33 cm-1 3614.52 cm-1, 3852.11 cm-1 and 2112.11 cm-1, respectively. The silver nanoparticles synthesized could have the potential application in agricultural, pharmaceutical and food industries as well as petrochemical industries for the clean - up of crude oil contaminated soils. J. Bio-Sci. 32(2): 31-44, 2024

Molecular Origins of Near-Infrared Luminescence in Molybdenum and Tungsten Oxyhalide Perovskites.

Materials with near-infrared (near-IR) luminescence are desirable for applications in communications and sensing, as well as biomedical diagnostics and imaging. The most used inorganic near-IR emitters rely on precise doping of host crystal structures with select rare-earth or transition metal ions. Recently, another class of materials with intrinsic near-IR emission has been reported. The compositions of these materials were initially described as vacancy-ordered halide double perovskites Cs2MoCl6 and Cs2WCl6, but further investigation by some of us on the compound reported as Cs2WCl6 revealed an oxyhalide instead, with a composition Cs2WO x Cl6-x , where 1 < x < 2. Here we demonstrate that the Mo compounds similarly possess the composition Cs2MoO x Cl6-x or Cs2MoO x Br6-x where 1 < x < 2. Preparing the pure halide appears harder for Mo than for W, and we have not succeeded in doing so. The distinctly different composition requires the coordination environment and oxidation state for the Mo and W centers to be reconsidered from what was assumed for the pure halides. In this work, we examine the mechanism for near-IR emission in these materials given their true structures and compositions. We demonstrate that the luminescence is due to the specific d-orbital splitting caused by the presence of oxygen in the distorted [MOX5]2- octahedra (X is Cl or Br). The fine structure in the emission spectra at low temperatures has been resolved and is attributed to vibronic coupling to the Mo-O and W-O bond stretches. Understanding the true structure and composition of these interesting materials, besides explaining the near-IR luminescence, suggests how this desirable emission can be realized and manipulated.

Unraveling the infrared spectrum of graphene oxide

The applicability of infrared spectroscopy toward graphene oxide (GO) and its derivatives is currently very limited, because the exact location of absorbance bands, originated by the main functional groups of GO, in the spectrum is still under debate. This obstacle leads to widespread misinterpretation of FTIR spectra in literature, and to invalid conclusions on attaining target functionalization reactions. In this work, by involving GO in four types of reactions, for the first time, we identify absorbance bands, originated by the main functional groups of GO: epoxides and tertiary alcohols. Also, we identify the bands, associated with carboxyl and carboxylate groups. In addition, we reconfirm the band assignment for absorbed water molecules (1619 cm−1) and covalent sulfates (1221 cm−1 and 1410 cm−1). Finally, we show conditions for appearance, and the exact position of the band of the C=C bond stretch. All together we accurately assign eight previously unidentified or incorrectly assigned absorbance bands in the fingerprint region of the spectrum, plus three bands which appear in the spectra of specific forms of GO. The assignment of the bands is independently confirmed by the 13C SSNMR spectroscopy. Summing up the newly assigned and the re-confirmed bands, for the first time, we report a complete library of the main absorbance bands in the FTIR spectrum of GO and GO derivatives.

An automated protocol to construct flexibility parameters for classical forcefields: applications to metal-organic frameworks.

In this work, forcefield flexibility parameters were constructed and validated for more than 100 metal-organic frameworks (MOFs). We used atom typing to identify bond types, angle types, and dihedral types associated with bond stretches, angle bends, dihedral torsions, and other flexibility interactions. Our work used Manz's angle-bending and dihedral-torsion model potentials. For a crystal structure containing N atoms in its unit cell, the number of independent flexibility interactions is 3(N atoms - 1). Because the number of bonds, angles, and dihedrals is normally much larger than 3(N atoms - 1), these internal coordinates are redundant. To reduce (but not eliminate) this redundancy, our protocol prunes dihedral types in a way that preserves symmetry equivalency. Next, each dihedral type is classified as non-rotatable, hindered, rotatable, or linear. We introduce a smart selection method that identifies which particular torsion modes are important for each rotatable dihedral type. Then, we computed the force constants for all flexibility interactions together via LASSO regression (i.e., regularized linear least-squares fitting) of the training dataset. LASSO automatically identifies and removes unimportant forcefield interactions. For each MOF, the reference dataset was quantum-mechanically-computed in VASP via DFT with dispersion and included: (i) finite-displacement calculations along every independent atom translation mode, (ii) geometries randomly sampled via ab initio molecular dynamics (AIMD), (iii) the optimized ground-state geometry using experimental lattice parameters, and (iv) rigid torsion scans for each rotatable dihedral type. After training, the flexibility model was validated across geometries that were not part of the training dataset. For each MOF, we computed the goodness of fit (R-squared value) and the root-mean-squared error (RMSE) separately for the training and validation datasets. We compared flexibility models with and without bond-bond cross terms. Even without cross terms, the model yielded R-squared values of 0.910 (avg across all MOFs) ± 0.018 (st. dev.) for atom-in-material forces in the validation datasets. Our SAVESTEPS protocol should find widespread applications to parameterize flexible forcefields for material datasets. We performed molecular dynamics simulations using these flexibility parameters to compute heat capacities and thermal expansion coefficients for two MOFs.

Peridynamic‐based modeling of elastoplasticity and fracture dynamics

AbstractThis paper introduces a particle‐based framework for simulating the behavior of elastoplastic materials and the formation of fractures, grounded in Peridynamic theory. Traditional approaches, such as the Finite Element Method (FEM) and Smoothed Particle Hydrodynamics (SPH), to modeling elastic materials have primarily relied on discretization techniques and continuous constitutive model. However, accurately capturing fracture and crack development in elastoplastic materials poses significant challenges for these conventional models. Our approach integrates a Peridynamic‐based elastic model with a density constraint, enhancing stability and realism. We adopt the Von Mises yield criterion and a bond stretch criterion to simulate plastic deformation and fracture formation, respectively. The proposed method stabilizes the elastic model through a density‐based position constraint, while plasticity is modeled using the Von Mises yield criterion within the bond of particle paris. Fracturing and the generation of fine fragments are facilitated by the fracture criterion and the application of complementarity operations to the inter‐particle connections. Our experimental results demonstrate the efficacy of our framework in realistically depicting a wide range of material behaviors, including elasticity, plasticity, and fracturing, across various scenarios.

Improved optimization for the neural-network quantum states and tests on the chromium dimer.

The advent of Neural-network Quantum States (NQS) has significantly advanced wave function ansatz research, sparking a resurgence in orbital space variational Monte Carlo (VMC) exploration. This work introduces three algorithmic enhancements to reduce computational demands of VMC optimization using NQS: an adaptive learning rate algorithm, constrained optimization, and block optimization. We evaluate the refined algorithm on complex multireference bond stretches of H2O and N2 within the cc-pVDZ basis set and calculate the ground-state energy of the strongly correlated chromium dimer (Cr2) in the Ahlrichs SV basis set. Our results achieve superior accuracy compared to coupled cluster theory at a relatively modest CPU cost. This work demonstrates how to enhance optimization efficiency and robustness using these strategies, opening a new path to optimize large-scale restricted Boltzmann machine-based NQS more effectively and marking a substantial advancement in NQS's practical quantum chemistry applications.

A Spectroscopic and Computational Evaluation of Uranyl Oxo Engagement with Transition Metal Cations.

We report the synthesis and characterization of five novel Cd2+/UO22+ heterometallic complexes that feature Cd-oxo distances ranging from 78 to 171% of the sum of the van der Waals radii for these atoms. This work marks an extension of our previously reported Pb2+/UO22+ and Ag+/UO22+ complexes, yet with much more pronounced structural and spectroscopic effects resulting from Cd-oxo interactions. We observe a major shift in the U═O symmetric stretch and significant uranyl bond length asymmetry. The ρbcp values calculated using Quantum Theory of Atoms in Molecules (QTAIM) support the asymmetry displayed in the structural data and indicate a decrease in covalent character in U═O bonds with close Cd-oxo contacts, more so than in related compounds containing Pb2+ and Ag+. Second-order perturbation theory (SOPT) analysis reveals that O spx → Cd s is the most significant orbital overlap and U═O bonding and antibonding orbitals also contribute to the interaction (U═O σ/π → Cd d and Cd s → U═O σ/π*). The overall stabilization energies for these interactions were lower than those in previously reported Pb2+ cations, yet larger than related Ag+ compounds. Analysis of the equatorial coordination sphere of the Cd2+/UO22+ compounds (along with Pb2+/UO22+ complexes) reveals that 7-coordinate uranium favors closer, stronger Mn+-oxo contacts. These results indicate that U═O bond strength tuning is possible with judicious choice of metal cations for oxo interactions and equatorial ligand coordination.

Anomalous bond lengthening in compressed magnetic doped semiconductor Ba(Zn0.95Mn0.05)2As2

Applying pressure has been evidenced as an effective method to control the properties of semiconductors, owing to its capability to modify the band configuration around Fermi energy. Correspondingly, structural evolutions under external pressures are required to analyze the mechanisms. Herein high-pressure structure of a magnetic doped semiconductor Ba(Zn0.95Mn0.05)2As2 is studied with combination of in-situ synchrotron X-ray diffractions and diamond anvil cells. The materials become ferromagnetic with Curie temperature of 105 K after further 20% K doping. The title material undergoes an isostructural phase transition at around 19 GPa. Below the transition pressure, it is remarkable to find lengthening of Zn/Mn−As bond within Zn/MnAs layers, since chemical bonds are generally shortened with applying pressures. Accompanied with the bond stretch, interlayer As−As distances become shorter and the As−As dimers form after the phase transition. With further compression, Zn/Mn−As bond becomes shortened due to the recovery of isotropic compression on the Zn/MnAs layers.

Remediation of phenanthrene by highly efficient CdS–SnS photocatalyst and its cytotoxic assessments

Cadmium sulfide-tin sulfide (CdS–SnS) nanoparticles are a novel kind of photocatalyst. These CdS–SnS nanoparticles are synthesized and characterized using UV–Vis, FT-IR, XRD, SEM-EDX, and DLS techniques, to understand their size distribution, crystalline nature, morphology, shape, optical properties, and elemental composition. This research offers insight into the efficient photocatalytic degradation of Phenanthrene (PHE) using CdS–SnS. The CdS–SnS NPs as photocatalyst can effectively photodegrade the polycyclic aromatic hydrocarbons (PAH) such as phenanthrene under simulated solar and UV light. UV–vis spectra of these nanoparticles exhibit peaks at 365 and 546 cm−1 respectively, the mean size of the CdS–SnS NPs in DLS is determined to be 78 nm. The CdS–SnS stretching frequency was observed at wave numbers below 700 cm−1, the absorption peak at 1123 cm−1 indicates the presence of C–N stretch or CS bond of thiourea, while the peak at 1350.38 cm−1 corresponds to the tris-amine C–N stretch in FT-IR. Additionally, the peaks observed at 2026 cm−1 indicate the presence of isothiocyanate (NCS). 1456.23 cm−1 represents the asymmetric scissor deformation vibration. EDAX revealed the presence of elemental Cd and Sn oxides. The antimicrobial studies showed that the CdS–SnS NPs at the concentration of 150 μg/mL, exhibit maximum inhibition (15 ± 1.25 mm) against the strains Proteus mirabilis followed by Staphylococcus epidermidis and Clostridium spp. Among fungal strains Colletotrichum spp. exhibits the maximum zone of inhibition (9 ± 0.25). This research also observed the cytotoxic effects of CdS–SnS NPs on HepG2 and ZF4 cells. HepG2 cells exhibited 50% inhibition at 50 μg/mL and 70% inhibition at 100 μg/mL concentrations, while ZF4 cells exhibited 50% inhibition at 50 μg/mL and 78% inhibition at 100 μg/mL concentrations, respectively. The parameters like concentration of PHE, concentration of CdS–SnS NPs, pH, and sources of irradiation on batch adsorption were examined to maximize the efficiency of the photodegradation process.

Decoding the origins of strength anisotropy in two-dimensional materials

Defects are inevitable in two-dimensional (2D) materials, which is widely recognized to affect the strength of 2D materials. It is known the uniaxial tension strength is significantly different along different directions of defective 2D materials. The defect induced strength anisotropy should have equal importance to defect strength, but unfortunately the mechanism and quantitative description of defect induced anisotropic strength are still unknown. In principle, the atomic origin of materials failure can be attributed to bond fracture, especially for 2D materials comprised of covalent bonds. From the viewpoint of bond fracture, the mystery of anisotropic strength of defective 2D materials is explored, that strength-orientation relations are consisted of complex multi-curves and each curve corresponds to the fracture of same bond. By considering the balance between bond stretch resulting from external loading and bond strength, a strength theory is developed, which can describe the anisotropic strength of graphene and h-BN with vast types of defects, like grain boundary, void, crack. This work deepens the understanding of defect induced anisotropic mechanical properties in 2D materials, which may facilitate defect engineering in 2D materials.

A unified strength criterion of diamane grain boundaries

Mechanical failure is one of the fundamental problems in solids, while the strength criterion, a measure of mechanical failure, is usually a phenomenological model that needs to be calibrated case by case. Diamane, a two-dimensional (2D) diamond is synthesized from graphene precursor, and the defect inherited from the graphene precursor is inevitable. Regrettably, the unified strength criterion of diamane is still a challenge due to the complexity of the stress state and defect structure. Here, the atomic configuration and stability of diamane grain boundaries (GBs) are first characterized through ab initio molecular dynamics (AIMD). Then, a unified strength criterion is proposed that can describe the mechanical failure of different diamane GBs under different loading states by using the concept of intrinsic bond strength. It is found the intrinsic bond strength is exclusively dependent on the local chemical environment of the bond and remains independent of loading states, GB structures and diamane thickness. In this regard, the bond fracture is initialized as the bond stretch stress arising from residual stress of defect and external loads exceeding the intrinsic bond strength. This work provides a physical understanding to construct the strength criterion of matter from the viewpoint of bond fracture analysis.

The Ductile/Brittle Transition for Materials Failure—Atomic Scale to Macroscopic Scale

Abstract This work is the continuation and completion to that initiated in the studies by Christensen (2022, “Perspective on the Bond Bending and Bond Stretching Effects of the Atomic Scale and Their Relationship to Ductile Versus Brittle Materials Failure,” J. Mech. Phys. Solids, 167, p. 104984; 2023, “Review of the Basic Elastic Mechanical Properties and Their Realignment to Establish Ductile Versus Brittle Failure Behaviors,” ASME Appl. Mech. Rev., 75(3), p. 031001) on the ductile/brittle transition for homogeneous and isotropic materials in uniaxial tensile failure. Starting here at the atomic level with the bonding involving both bond bending and bond stretching effects, there then is given the development of the ductile/brittle transition for a type of cubic symmetry in the individual crystals of the composing polycrystalline material. Thereafter, a complementary derivation is given for the ductile/brittle transition at the macroscopic level involving a specific form of the strain energy. The two results are found to be compatible and mutually verifying, thereby finishing the investigation.

Harmonic and anharmonic studies on THz spectra of two vanillin polymorphs

Polymorphism commonly exists in organic molecular crystals. The fingerprint features in low-frequency vibrational range are important information reflecting different intermolecular interactions of polymorphs. Interpreting these features is very helpful to understand vibrational property of polymorphs and reveal the thermodynamic stability. In this work, the low-frequency vibrations of form I and II of vanillin are investigated using terahertz time-domain spectroscopy. Static DFT calculation and ab initio molecular dynamics (AIMD) are employed to interpret their low-frequency vibrations of both forms in harmonic and anharmonic ways, respectively. Their low-frequency vibration characteristics in harmonic calculations are discussed, and anharmonic mode couplings between OH bond stretch and the stretching and bending motion of hydrogen bonds are uncovered. Moreover, the thermodynamic energies including electronic potential energy and vibrational/kinetic energy arising from nuclear motions are calculated. The result reveals that the stability order of the two forms is mainly dependent on their electric potential energy difference.

A formally exact theory to construct nonreactive forcefields using linear regression to optimize bonded parameters.

This article derives theoretical foundations of force field functional theory (FFFT). FFFT studies topics related to the functional representation of nonreactive forcefields to achieve various desirable properties such as: (a) formal exactness of the forcefield's energy functional under certain conditions, (b) a formally exact ansatz separating the bonded potential energy from the nonbonded potential energy within a bonded cluster in a way that enables bonded parameters to be optimized using linear regression instead of requiring nonlinear regression, (c) the potential energy's continuous differentiability to various orders with respect to energetically accessible internal coordinate displacements within a subdomain defined by one electronic ground state, (d) forcefield design that guarantees the reference ground-state geometry is exactly reproduced as an equilibrium structure on the forcefield's potential energy landscape, (e) reasonably accurate and broadly applicable frugal model potentials, (f) computationally efficient embedded feature selection that identifies and removes unimportant forcefield terms, (g) well-designed methods to parameterize the forcefield from quantum-mechanically-computed and (optionally) experimental reference data, and (h) forcefields that approximately reproduce experimentally-measured properties. This article also introduces: (1) an angle-bending model potential that more accurately describes physical dynamics and is continuously differentiable to all orders with respect to internal coordinate displacements even when the bond angle is linear (i.e., θ = π (180°)) and (2) a first-principles-derived stretch potential that accurately describes short-range Pauli repulsion and the long-range bond dissociation energy. This new angle-bending potential gave good agreement to CCSD quantum-chemistry calculations for CaH2, CO2, H2O, HNO, Li2O, NO2, NS2, SF2, SiH2, and SO2 molecules. This new bond-stretch potential reproduced the first 12+ and 30+ vibrational energy levels of H2 and O2 molecules, respectively, within a few percent of experimental values. Studying the C-F bond stretch in C6F6 as an example, the new ansatz (item (b) above) reduced sensitivity of the optimized force constant's value to choice of nonbonded interaction parameters by an order of magnitude compared to the old ansatz. Normal mode analysis of optimized flexibility models for CO2, H2O, HNO, and SO2 molecules yielded vibrational transition frequencies within a few percent of experimental values. These results demonstrate advantages of this new approach.

From loose to tight: unveiling bond stretch isomerism in π-complexes of Li, Na and K.

The study investigates the phenomenon of bond stretch isomerism (BSI) in complexes formed between alkali metals (Li, Na, K) and various non-aromatic, aromatic hydrocarbons, as well as heteroaromatic systems. The research employs density functional theory (DFT) calculations to optimize complex geometries and analyze their electronic structures using molecular electrostatic potential (MESP), charge, and spin density analyses. The results reveal that these complexes can exist in two distinct configurations: 'loose' long-bond isomers (lbi) that retain the original hydrocarbon geometry and 'tight' short-bond isomers (sbi) that undergo geometrical distortion upon complexation, with sbi generally being more stable. The interconversion between lbi and sbi occurs through a transition state. The study highlights the crucial role of electron transfer in BSI, with sbi involving valence electron transfer from the metal to the hydrocarbon, leading to zwitterionic radical complexes. In contrast, lbi exhibit a slight electron density transfer from the hydrocarbon to the metal. The presence of low-energy transition states between lbi and sbi suggests a dynamic shuttling mechanism for alkali metals, particularly Li, on hydrocarbon surfaces. The study identifies Li complexes as potential candidates for anode materials in batteries due to their stability and electron transfer properties, offering valuable insights into the design of advanced materials for energy storage applications.

A Perusal of Phenolics Within Polar Peel Fractions of Malus domestica var Maharaji via Hyphenated Techniques Cum Anti-microbial with REMA and Tyrosinase Inhibitory Potential thereof

This study aims to scrutinize the phenolic secondary metabolites in the polar peel decocture of Malus domestica var Maharaji via hyphenated techniques along with the study of the antibacterial, anti-candida, and tyrosinase inhibitory potential of bioactive compound-rich fractions. Preliminary phenolics go over was performed together with thin layer chromatography before the polar decocture was subjected to hyphenated techniques. FTIR investigation revealed the C-O bonds as in phenols, O-H bond stretch, and vibrations of alcohols and carboxylic acids as well as portrayed the C-H and &gt;C=O stretches among other functional groups all of which are representative of phenolic and polyphenolic compounds. GC-MS perusal demonstrated the presence of bioactive compounds like Quercetin (13.04%), Ascorbic acid (6.48%), p-Coumaric acid (6.17%), Caffeic acid (5.69 %), Mallic acid (5.44%), Apigenin (5.28%), Citric acid (5.15%), Gallic acid (4.38%), Cyanidin (3.52%), and Ferulic acid (3.51%). Kirby-Bauer method followed by the resazurin microtiter assay technique (REMA) for MIC/MBC against six MTCC bacterial strains and one yeast, all producing stubborn opportunistic infection in humans, was used to assess the antibacterial property of all the bioactive rich fractions. Some fractions comparatively revealed a good activity index (AI) against tested microbes. MIC concentrations for bacteria ranged from 15-24 mg/ml while a lower MBC value recorded was 18 mg/ml. Methanol fraction revealed significant tyrosinase inhibitory activity by revealing IC50 of 980.98 µg/ml when L-Tyrosine was substrate and IC50 of 830.68 µg/ml when L-DOPA was substrate when juxtaposed to standard kojic acid that revealed IC50 of 128.822 µg/ml when L-Tyrosine was substrate and IC50 of 149.43 µg/ml when L-DOPA was substrate. The bioactive compounds possessed by the fractions, may be synergistically, turned out to be more effective in the diphenolase reaction and kojic acid acts more effectively in the monophenolase one. It was inferred that peel phenolics of this malus variety have a lot of therapeutic potential in the context of bacterial infections and pigmentation disorders.

Novel Terahertz-Based Radiation Treatment of Alzheimer Disease

Alzheimer’s Disease Facts and Figures, an annual report released by the Alzheimer’s Association, reveals the burden of Alzheimer’s and dementia on individuals, caregivers, government and the nation’s health care system. Per the special report, More Than Normal Aging: Understanding Mild Cognitive Impairment (MCI), it is estimated 10% to 15% of individuals with MCI go on to develop dementia each year. Because of the narrow brain-blood barrier every medicine designed to treat Alzheimer’s failed due to inability of complex and large molecules to penetrate this barrier. &lt;strong&gt;&lt;span class="correspondence-author"&gt;Four steps of Alzheimer’s treatment by using proprietary Magtera Technology.&lt;/span&gt;&lt;/strong&gt; &lt;span class="correspondence-author"&gt;&lt;strong&gt;First step:&lt;/strong&gt;&lt;/span&gt; Detect the THz modes for Aβ42 Oligomer. or any other micro bio structures proven to be responsible for Alzheimer’s. The most probable THz modes would be intermolecular modes: librations, low frequency bond vibrations; hydrogen bond stretches and distortions; molecular rotations. There are plenty of such modes. &lt;span class="correspondence-author"&gt;&lt;strong&gt;Second step:&lt;/strong&gt;&lt;/span&gt; detect the THz modes of healthy brain tissue. &lt;span class="correspondence-author"&gt;&lt;strong&gt;Third step:&lt;/strong&gt;&lt;/span&gt; Find a THz window of penetration in brain fluids that corresponds to one of these modes by using the highly tunable THz Magnon Laser that bridges the THz Gap and covers the whole THz spectrum. &lt;span class="correspondence-author"&gt;&lt;strong&gt;Fourth step: &lt;/strong&gt;&lt;/span&gt; Apply high power THz radiation by using the THz Magnon Laser at resonance frequencies that correspond to Aβ42 Oligomer molecular excitations but do nor coincide with THz modes of healthy brain tissue, and eradicate Aβ42 Oligomer molecules.