Additional Properties Research Articles

HIV infection and ART use are associated with altered plasma clot characteristics in Black South Africans.

Human immunodeficiency virus (HIV) and antiretroviral treatment (ART) are both associated with hypercoagulability. Altered clot properties could be a potential mechanism thereof. We aimed to investigate the association of HIV and ART, with fibrinogen and plasma clot properties in a group of Black South Africans. At baseline, 151 newly diagnosed people living with HIV (PLWH) and 176 controls were recruited. Some PLWH subsequently commenced with ARTs (n = 70) while others remained ART-naïve (n = 81). Fibrinogen and clot properties (turbidity assay) were investigated from baseline to 5-year follow-up. A sub-group of 21 women (n = 10 ART-treated; n = 11 ART-naïve) with HIV was systematically selected and matched with 12 controls, and additional clot properties (rheometry, permeability and fibre diameter) were investigated. Fibrinogen was lower in the HIV groups compared to the controls, while % γ' fibrinogen was higher. PLWH had shorter lag times and lower maximum absorbance than the controls (p<0.05). Their CLTs on the other hand were longer. Most variables increased over time in all groups, but differences in the degree of change over time was observed for lag time (p = 0.024) and permeability (p = 0.03). Participants who commenced with ART had a tendency of delayed clot formation (p = 0.08) and increased clot permeability (p = 0.005). PLWH had lower total fibrinogen concentration and formed less dense clots. They also formed clots that were more difficult to lyse, which likely not resulted from altered clot properties. ART use (NNRTI's) had a moderately protective effect, delaying clot formation, and increasing clot permeability.

Calibration complex of radio measuring equipment

Modern trends in the development of radio measuring equipment require improvement of the principles of metrological support of these devices and corresponding reference base. The new approach is based on the digitalisation of equipment, programming of measurement procedures, and the transition from single measurement standards to measurement complexes. The paper describes the complex developed at the NSC “Institute of Metrology” and designed for verification and calibration of a wide range of radio measuring equipment, where all these approaches are realised, presents methodological, software and hardware features of its construction, as well as the advantages and possibilities of this approach in metrological practice. On the example of the method of “Bessel Function Zeros”, which was somewhat forgotten due to the cumbersome nature of its implementation by analogue methods and equipment, it is shown that with the new approach this method gets a “second birth”, moreover, at a higher metrological level. It is shown that the use of direct digital synthesis oscillators can significantly improve the “electronic counting frequency meter” method, in particular, prevent the phenomenon of “frequency capture”, which limited the capabilities of the method and introduced additional measurement uncertainty. Moreover, the additional properties of the complex associated with the use of the R&amp;S FSL spectrum analyser with the K7 analogue signal demodulator option are explained in more detail. A list of other methods realised in the complex is given, among which the “combination frequencies” method, deserves a special attention, providing the highest resolution in measuring nonlinear distortions of both quasi-harmonic and modulated signals. It is shown that the complex is a flexible apparatus, the work programme of which can be adjusted and supplemented. Information on the structure of the complex, hardware solution of a number of nodes, programming language, etc. is given.

New Additivity Properties of the Relative Entropy of Entanglement and Its Generalizations

New Additivity Properties of the Relative Entropy of Entanglement and Its Generalizations

Carbon‐Based Nanomaterials for Antiviral Applications

AbstractIn the antimicrobial resistance era, carbon‐based nanomaterials (CBNs) such as fullerenes, carbon dots, graphene, and their derivatives are promising therapeutic tools in combating viral diseases. This review shows that these materials have broad‐spectrum antiviral activity against 33 viruses belonging to different Baltimore groups. CBNs also exhibit antimicrobial activity against bacteria and fungi and possess a low risk of selecting for resistance, since their primary mode of antimicrobial action involves physically damaging the microbes. CBNs also offer additional promising properties, including enhanced antiviral effectiveness under diverse types of irradiation and facilitating antiviral immune responses. Their potential as antiviral agents is still in its infancy and future research should focus on their toxicity, antiviral mechanisms, pharmacokinetics, and bioavailability. They are also potential antiviral materials for preventing the transmission of viral diseases for use in face masks, shields, hospital and airport surfaces, and elevators, among others. It is anticipated that CBNs will play an increasingly significant role in the fight against viruses and infectious diseases.

Psychometric evaluation of the patient-reported experience of cognitive impairment in schizophrenia (PRECIS) scale

BackgroundCognitive impairment associated with schizophrenia (CIAS) represents a distinct, persistent, and core group of schizophrenia symptoms. Cognitive symptoms have been shown to have an impact on quality of life. There are several published CIAS measures, but none based on direct patient self-report. It is important to capture the patient’s perspective to supplement performancebased outcome measures of cognition to provide a complete picture of the patient’s experience. This paper describes additional validation work on the Patient-Reported Experience of Cognitive Impairment in Schizophrenia (PRECIS) instrument.MethodsData from two large, international, pharmaceutical clinical trials in medically and psychiatrically stable English-speaking patients with schizophrenia and 88 healthy controls were analyzed. An exploratory factor analysis (EFA) was conducted in one trial (n = 215), using the original 35-item PRECIS. The factor structure suggested by EFA was further evaluated using item response theory (IRT; Samejima’s graded response model), and tested using confirmatory factor analysis (CFA). Both EFA and CFA results were tested in a second trial with similar inclusion/exclusion characteristics (n = 410). Additional statistical properties were evaluated in healthy controls.ResultsEFA suggested that the best solution after item reduction suggested a factor structure of 6 factors based on 26 items (memory, communication, self-control, executive function, attention, sharpness of thought), supporting a total score, with an additional 2-item bother score (28 items in all). IRT analysis indicated the items were well-ordered within each domain. The CFA demonstrated excellent model fit, accounting for 69% of the variance. The statistical properties of the 28-item version of the PRECIS were confirmed in the second trial. Evidence for internal consistency and test-retest reliability was robust. Known-groups validity was supported by comparison of healthy controls with patients with schizophrenia. Correlations indicated moderate associations between PRECIS and functioning instruments like the Schizophrenia Cognition Rating Scale (SCoRS), but weak correlations with performance-based outcomes like MATRICS Consensus Cognitive Battery (MCCB).DiscussionUsing two clinical trial samples, we identified a robust factor structure for the PRECIS and were able to replicate it in the second sample. Evaluation of the meaningful score difference (MSD) should be repeated in future studies, as these samples did not show enough change for it to be evaluated.ConclusionsThis analysis provides strong evidence for the reliability and validity of the PRECIS, a 28-item, patient-reported instrument to assess cognitive impairment associated with schizophrenia. The correlation with functioning and the weak correlation with performance on cognitive tasks suggests that patient reports of cognitive impairment measure a unique aspect of patient experience.

Bi-Squashing S2,2-Designs into (K4 − e)-Designs

A double-star Sq1,q2 is the graph consisting of the union of two stars, K1,q1 and K1,q2, together with an edge joining their centers. The spectrum for Sq1,q2-designs, i.e., the set of all the n∈N such that an Sq1,q2-design of the order n exists, is well-known when q1=q2=2. In this article, S2,2-designs satisfying additional properties are investigated. We determine the spectrum for S2,2-designs that can be transformed into (K4−e)-designs by a double squash (bi-squash) passing through middle designs whose blocks are copies of a bull (the graph consisting of a triangle and two pendant edges). Here, the use of the difference method enables obtaining cyclic decompositions and determining the spectrum for cyclic S2,2-designs that can be purely bi-squashed into cyclic (K4−e)-designs (the middle bull designs are also cyclic).

Strassen's rank additivity for small tensors, including tensors of rank less or equal 7

The article is concerned with the problem of additivity of the tensor rank. That is, for two independent tensors, we study when the rank of their direct sum is equal to the sum of their individual ranks. The statement saying that additivity always holds was previously known as Strassen's conjecture (1969) until Shitov proposed counterexamples (2019). They are not explicit and only known to exist asymptotically for very large tensor spaces. In this article, we present families of pairs of small three-way tensors for which the additivity holds. For instance, over the base field C, it is the case if both tensors are of rank less or equal 7. This proves that a pair of 2×2 matrix multiplication tensors has the rank additivity property. We show also that the Alexeev-Forbes-Tsimerman substitution method preserves the structure of a direct sum of tensors.

A simple fluorescent “Turn-Off” Schiff base sensor for Cu2+ and Fe2+ ions and its applications in real water sample analysis and logic gate construction

A novel imidazole-based Schiff base ligand (Z)-N’-((1H-imidazol-2-yl)methylene)-2-hydroxybenzohydrazide (IMBH), was effectively synthesized and characterized using spectroscopic methods. Chemosensor IMBH’s chelation enhanced fluorescence (CHEF) is responsible for its extremely selective and sensitive detection of Cu2+ and Fe2+ ions in DMSO solutions. Adding different metal ions (30 μM) allowed for the determination of the fluorescence behaviour of IMBH (50 μM). The findings showed that, only for Cu2+ and Fe2+ ions, a notable fluorescence quenching in the emission was seen at 465 nm with an excitation at 320 nm. Furthermore, the Job’s plot and mass spectral analysis showed that IMBH bound Cu2+ and Fe2+ ions at a 2:1 (Ligand:Metal) ratio. For the Cu2+ and Fe2+ ions, the limit of detection (LOD) was found to be 0.204 × 10−9 M and 0.201 × 10−9 M, respectively. On the other hand, IMBH was successfully utilized for the quantitative analysis of Cu2+ and Fe2+ ions in real water samples and logic gate construction. In addition, optoelectronic and structural properties of the IMBH and Fe(II) and Cu(II) complexes were determined by solvent phase DFT calculations.

Evaluation and comparison of lattice-based digital signature of the "Digital Signature Schemes" PQC NIST competition

Over the past decade, post-quantum cryptography has reached a tipping point; institutional bodies and stakeholders have initiated standardization and deployment, and various projects have achieved a reasonably high level of progress and even deployment and implementation. In July 2022, at the end of Round 3 of the NIST's PQC competition, 3 candidates were proposed for the NIST standardization for post-quantum digital signatures scheme: one signature scheme based on MLWE (Crystals-Dilithium), one signature based on NTRU (Falcon), and one signature based on hash (Sphincs+). Although the performance profiles and “black-box” security of these schemes are well understood, resistance to side-channel attacks remains a weak point for all of them. After that, the NIST announced that the PQC standardization process is continuing with a fourth round, with the following KEMs still under consideration: BIKE, Classic McEliece, HQC, and SIKE. However, there are no candidates of digital signature schemes left for consideration. As such, the NIST has issued a call for additional digital signature proposals to be considered in the PQC standardization process. Acceptance of documents ended on June 1, 2023. As a result, 40 candidates were selected for the role of DS standard, namely: 6 DS algorithms based on codes, one DS algorithm based on isogenies, 7 DS algorithms based on lattice operations, 7 candidates for the role of DS algorithm based on the MPC method -in-the-Head and 10 algorithms based on multivariate transformations, 4 DS schemes were selected based on symmetric cryptographic transformations, and 5 more candidates based on other types of cryptographic transformations. The NIST is primarily interested in additional general purpose signature schemes that are not based on structured lattices. For certain applications, such as certificate transparency, the NIST may also be interested in signature schemes that have short signatures and fast verification. The NIST is open to receiving additional materials based on structured lattices, but intends to diversify post-quantum signature standards. Therefore, any structured array-based signature proposal would need to significantly outperform CRYSTALS-Dilithium and FALCON in relevant applications and/or provide significant additional security properties to be considered for standardization. Thus, the purpose of this paper is to analyze, evaluate, and compare digital signature algorithms based on lattice cryptography, an additional PQC NIST competition, and compare them with already standardized lattice-based DS mechanisms, such as CRYSTALS-Dilithium and FALCON.

Novel hard and unusual superconducting monoclinic phase of FeB2C2: An ab initio evolutionary study

This study focuses on conducting an ab initio evolutionary investigation to search for stable polymorphs of iron diborocarbides with the formula FeB2C2. We also examined other forms of C contents, including FeB3C and FeBC3. Our findings reveal that the lowest energetic structure of FeB2C2 is a semimetallic monoclinic phase with a space group (s.g.) of C2/m and a metastable metallic phase of FeB2C2 is an orthorhombic structure with s.g. of Pmmm. In addition, structural and relative properties of FeB3C and FeBC3 are performed and discussed to compare with FeB2C2. All predicted structures are dynamically and elastically stable, verified without negative phonon frequency and Born criteria, respectively. We also analyzed the energetic stability through calculated cohesive and formation energies, which showed that C2/m-FeB2C2 is stable at low pressure. Interestingly, the C2/m and Pmmm phases of FeB2C2 are hard materials with Vickers hardness (Hv) of 22.40 and 27.52 GPa, respectively. Additionally, we examined the electron–phonon coupling of both FeB2C2 phases. Unexpectedly, we found that the semimetallic C2/m-FeB2C2 phase is a superconductor with a significant superconducting temperature (Tc) exceeding 6 K. These findings provide some novel results for the Fe–B–C system and pave the way for investigating other metal borocarbides and related ternary compounds.

Strain-Programmed Adhesive Patch for Accelerated Photodynamic Wound Healing.

As an alternative to tissue adhesives, photochemical tissue bonding has been investigated for advanced wound healing. However, these techniques suffer from relatively slow wound healing with bleeding and bacterial infections. Here, we present the versatile attributes of afterglow luminescent particles (ALPs) embedded in dopamine-modified hyaluronate (HA-DOPA) patches for accelerated wound healing. ALPs enhance the viscoelastic properties of the patches, and the photoluminescence (PL) and afterglow luminescence (AL) of ALPs maximize singlet oxygen generation and collagen fibrillogenesis for effective healing in the infected wounds. The patches are optimized to achieve the strong and rapid adhesion in the wound sites. In addition, the swelling and shrinking properties of adhesive patches contribute to a non-linear behavior in the wound recovery, playing an important role as a strain-programmed patch. The protective patch prevents secondary infection and skin adhesion, and the patch seamlessly detaches during wound healing, enabling efficient residue clearance. In vitro, in vivo, and ex vivo model tests confirm the biocompatibility, antibacterial effect, hemostatic capability, and collagen restructuring for the accelerated wound healing. Taken together, this research collectively demonstrates the feasibility of HA-DOPA/ALP patches as a versatile and promoting solution for advanced accelerated wound healing, particularly in scenarios involving bleeding and bacterial infections. This article is protected by copyright. All rights reserved.

Comprehensive structural analysis, magnetic, elastic, and optical properties of Cu–Ni–Co spinel and its potential applications

This work investigates the Cu0·6Ni0·2Co0·2FeAlO4 (CNCFAO) spinel nanoparticle, focusing on its structural, magnetic, elastic, and optical properties. The structural analysis provided various parameters, such as lattice parameter, crystallite size, and bond lengths, which were compared to theoretical values. The force constants of the sample were used to calculate stiffness constants (C11, C12, and C44), which in turn were used to determine elastic moduli such as the bulk modulus (B), longitudinal modulus (L), and rigidity modulus (G). The calculated Pugh ratio (B/G) indicated the brittle mechanical nature of the sample, while the Poisson ratio (σ) was estimated as σ = 0.25, consistent with isotropic elasticity theory. The sample demonstrated a low coercive field, indicating its potential for soft magnetic devices. Optical characteristics were evaluated using the Tauc method, revealing a direct optical transition with estimated band-gap (Eg) and Urbach (Eu) energies of 2.38 eV and 0.59 eV, respectively. Additional optical properties, including the penetration depth, refractive index, and extinction coefficient, were thoroughly examined. These results provide valuable insights into the potential optoelectronic applications of the synthesized sample.

The Media and Technology Usage and Attitudes Scale (MTUAS): Adaptation and Psychometric Analysis for University Students in Saudi Arabia

The aim of this study was to adapt an Arabic version of the Media and Technology Usage and Attitudes Scale (MTUAS) to the Saudi culture and examine the psychometric properties of the adapted version in a sample of 1,709 undergraduate students. Evidence of construct validity and internal consistency reliability was first compiled through exploratory and confirmatory factor analyses (EFA and CFA) and Cronbach’s α coefficients. Multigroup CFA (MGCFA) was then conducted to test gender-related measurement invariance. The EFA yielded nine factors for the Usage scale and four factors for the Attitudes scale of the MTUAS, all of which were satisfactorily confirmed via CFA. Factors of the MTUAS exhibited adequate to good reliability and were gender invariant. Overall, the Arabic MTUAS displayed good psychometric properties in the Saudi undergraduate student population and was gender unbiased. Therefore, it can be used confidently across educational, public health, and marketing research in Saudi and Arabic contexts. Nevertheless, it is important to note that other psychometric properties, such as criterion-related validity, were not compiled in the present study, and the generalizability of the current findings might be restricted to the Saudi undergraduate student population. Hence, these limitations should be given more consideration in future studies by examining additional psychometric properties of the Arabic MTUAS and using comprehensive national data.

Therapeutic potential of selenium nanoparticles synthesized by mangrove plant: Combatting oral pathogens and exploring additional biological properties

BackgroundOver the past few decades, nanoparticles have been widely employed to limit the growth of cancer both in vivo and in vitro, as well as many dangerous bacteria, fungi, and viruses. In traditional medicine, a marine plant called Rhizophora mucronata is frequently used to treat skin conditions, inflammation, and diabetes. ObjectiveEvaluate the efficacy of selenium nanoparticles synthesized using mangrove plant extracts in combating oral pathogens and assess their potential for additional biological properties towards the development of novel therapeutic interventions for oral infections and related conditions. MethodsIn the current study, R. mucronata was utilized to create selenium nanoparticles (SeNPs) in an environmentally friendly manner. The elements of the material were identified using EDX spectroscopy, its shape was examined using SEM, and its surface Plasmon resonance was measured using UV–Vis spectroscopy. Moreover, FT-IR was used to identify the SeNPs' functional groups. ResultsThe produced nanoparticles ranged in size from 20 to 60 nm and had a spherical form. Later analyses concentrated on the ability of the synthesized nanoparticles to combat common oral pathogens that cause dental cavities and other oral diseases. The marine plant-derived SeNPs showed notable zones of inhibition in addition to lethal actions against these oral infections. These nanoparticles also demonstrated anti-inflammatory and potentially effective DPPH radical scavenging qualities. ConclusionBased on the above reported results, it can be concluded that SeNPs generated by R. mucronata have significant potential for a variety of pharmacological and medical uses.

Opportunities to reduce environmental burden by recycling fabric waste in a woollen fabric company

PurposeWool fiber is accepted as one of the natural and renewable sources and has been used in the apparel and textile industry since ancient times. However, wool fiber has the highest global warming potential value among conventional fibres due to its high land use and high methane gas generation. This study aimed to recycle the wool fabric wastes and also to create a mini eco-collection by using the produced yarns.Design/methodology/approachThis manuscript aimed to evaluate the fabric wastes of a woolen fabric producer company. Fabric wastes were opened with two different opening systems and fiber properties were determined. First, conventional ring yarns were produced in the company’s own spinning mill by mixing the opened fibres with the long fiber wastes of the company. In addition, opening wastes were mixed with different fibres (polyester, long wool waste, and Tencel fibres) between 25% and 70% in the short-staple yarn spinning mill and used in the production of conventional ring and OE-rotor yarns. Most of the yarns contained waste fibres at 50%. Recycled and virgin yarns were used as a weft and warp yarn and a total of 270 woven fabric samples were obtained and fabric properties were examined. Also, a fabric collection was created. A life cycle assessment (LCA) was made for one of the selected yarns.FindingsAt the end of the study, it was determined that it was possible to produce yarn and fabric samples from fiber blends containing high waste fiber ratios beyond 50%. All the woven fabric samples produced from conventional ring and OE-rotor yarns gave higher breaking, tearing and stitch slip strength values in the weft and warp direction than limit quality values of the company. In addition, abrasion resistance and WIRA steam stability properties of the fabric samples were also sufficient. Environmental analysis of the recycling of the wastes showed a possible decrease of about 9940034.3 kg CO2e per year in the global warming potential. In addition, fiber raw material expenses reduced yarn production cost about 50% in case of opened fabric waste usage. However, due to insufficient pilling resistance results, it was decided to evaluate the woven fabrics for the product groups such as shawls and blankets, where pilling resistance is less sought.Originality/valueThe original aspects of the article can be summarized under two headings. First, there are limited studies on the evaluation of wool wastes compared to cotton and polyester fibres and the number of samples examined was limited. However, this study was quite comprehensive in terms of opening type (rag and tearing), spinning systems (long and short spinning processes), fiber blends (waste 100% and blends with polyester, long wool waste and Tencel fibres) and yarn counts (coarser and finer). Recycled and virgin yarns were used as a weft and warp yarn and a total of 270 woven fabric samples were obtained using different colour combinations and weave types. All processes from fabric waste to product production were followed and evaluated. Life cycle assessment (LCA) and cost analysis was also done. The second unique aspect is that the problem of a real wool company was handled by taking the waste of the woolen company and a collection was created for the customer group of the company. Production was made under real production conditions. Therefore, this study will provide important findings to the research field about recycling, sustainability etc.

ANALYSIS OF FILES IN STL-FORMAT AS THE BASIS OF MODELING FOR 3D PRINTING OF BUILDING OBJECTS

Problem statement. The integration of advanced technologies in the field of software at the stages of construction becomes one of the key tasks of designers. Creating objects using 3D printing requires the use of appropriate high-tech solutions. One of these solutions consists in the analysis of the process of converting three-dimensional models into a control code for 3D printers, in particular, the analysis of files in STL format. The efficiency of manufacturing construction structures and structures by 3D printing depends primarily on this analysis. Purpose of the article. This study aims at an in-depth analysis of STL files in light of the growth of additive manufacturing and the advancement of digital technologies in the construction industry. The purpose of the work is to provide a comprehensive overview of the basic information related to the use of this format, including methods for calculating the area and volume of the STL grid. Identification and analysis of typical errors that may occur when working with files of this format and definition of key criteria for evaluating the geometric quality of the grid. Consideration of strategies and alternative approaches to overcome possible drawbacks that may arise when using the STL format. Creation of a comprehensive view of this format and provision of appropriate recommendations for further improvement of the processes of working with it. Conclusion. The study of STL files plays an important role in the development of additive manufacturing and digital technologies in the construction industry. This study aims to provide a detailed overview of the basic information related to the use of this format, including methods for calculating the area and volume of an STL mesh, which are crucial for efficient modeling and production of structures. During the research, a number of errors were identified and key criteria for assessing the geometric quality of the grid were determined. This includes correctly orienting normals, detecting and correcting overlaps, intersections, and isolated faces. For further research, it is proposed to consider alternative options for overcoming some of the shortcomings of the STL format. For example, you can consider automated methods of detecting and correcting errors in the network, developing new file formats with greater functionality and support for additional model properties. Investigating such alternatives can help improve the efficiency and accuracy of file use in construction and additive manufacturing.

The conformational landscape of fold-switcher KaiB is tuned to the circadian rhythm timescale.

How can a single protein domain encode a conformational landscape with multiple stably-folded states, and how do those states interconvert? Here, we use real-time and relaxation-dispersion NMR to characterize the conformational landscape of the circadian rhythm protein KaiB from Rhodobacter sphaeroides. Unique among known natural metamorphic proteins, this variant of KaiB spontaneously interconverts between two monomeric states: the "Ground" and "Fold-switched" (FS) state. KaiB in its FS state interacts with multiple binding partners, including the central KaiC protein, to regulate circadian rhythms. We find that KaiB itself takes hours to interconvert between the Ground and KaiC binding-competent FS state, underscoring the ability of a single protein sequence to encode the slow process needed for its biological function. We reveal that the rate-limiting step between the Ground and FS state is the cis-trans isomerization of three prolines in the C-terminal fold-switching region by demonstrating acceleration of interconversion by the prolyl cis/trans isomerase CypA. The interconversion proceeds through a "partially disordered" (PD) state, where the N-terminal half remains stably folded while the C-terminal half becomes disordered. We discovered two additional properties of KaiB's landscape: firstly, the Ground state experiences cold denaturation: at 4°C, the PD state becomes the majorly populated state. Secondly, the Ground state exchanges with a fourth state, the "Enigma" state, on the millisecond timescale. We combine AlphaFold2-based predictions and NMR chemical shift predictions to suggest that this "Enigma" state represents a beta-strand register shift that eases buried charged residues in the Ground state. These results provide mechanistic insight in how evolution can design a single sequence that achieves specific timing needed for its function.

Comparative Evaluation of Microhardness and Solubility of Different Combinations of Antibiotic Powders Added to Glass Ionomer Cement: An In Vitro Study.

The imbalance between remineralization and demineralization leads to the formation of secondary caries. Fluoride-releasing ability has been the characteristic property of glass ionomer cement (GIC), but it is uncertain if this property alone will be sufficient for the cessation of the growth of the organisms. Therefore, a restorative material with additional bacteriostatic properties needs to be introduced. To evaluate the microhardness and solubility of the conventional GIC after adding different combinations of antibiotic powders. In this study, the three groups were conventional GIC (group I), GIC + metronidazole + ciprofloxacin (group II), and GIC + metronidazole + amoxicillin/clavulanic acid (group III). The concentration of the double antibiotic combination was maintained at 1.5% w/w. The antibiotic powders were added to the GIC and evaluated for microhardness and solubility of the specimens. The mean microhardness level of group II was the highest, which was statistically significant using analysis of variance (ANOVA) with a p-value of 0.022. The comparison of each group's solubility in different solutions was not statistically significant. Along with the conventional properties of GIC, an additional therapeutic gain can also be obtained by incorporating various combinations of antibiotics, thereby arresting the progression of caries at the site of infection itself. This new approach shall help in community health programs, where treatment of a large population needs to be done within a short span of time and arrest the progression of caries activity in deep caries. Benson TL, Sogi S, Jain M, et al. Comparative Evaluation of Microhardness and Solubility of Different Combinations of Antibiotic Powders Added to Glass Ionomer Cement: An In Vitro Study. Int J Clin Pediatr Dent 2024;17(6):619-624.

Self-Assembled Chiral Film Based on Melanin Polymers.

Chirality plays a fundamental role in natural phenomena, yet its manifestation on solid surfaces remains relatively unexplored. In this study, we investigate the formation of chiroptical melanin-based self-assembled films on quartz substrates, leveraging mussel-inspired surface chemistry. Water-soluble porphyrins serve as molecular synthons, facilitating the spontaneous formation of hetero-aggregates in phosphate-buffered saline containing L- or D-DOPA. Spectroscopic analysis reveals chiral transfer from DOPA enantiomers to porphyrin hetero-aggregates, followed by the disruption of these latter and subsequent generation of chiral melanin structures in solution. Quartz substrates inserted into these solutions spontaneously accumulate homogeneous melanin-like films over days, demonstrating the feasibility of self-assembly. The resulting films exhibit characteristic UV/Vis and CD spectra, with distinct signals indicating successful chiral induction. Interestingly, the AFM characterizations reveal a distinct surface morphology, and in addition, some thermal and mechanical properties have been taken into account. Overall, this study sheds light on the formation, stability, and chiroptical properties of melanin-based films, paving the way for their application in various fields.

On solving terminal approach and evasion problems for linear discrete-time systems under state constraints

The paper is devoted to elaboration of polyhedral techniques for solving two control problems for linear discrete-time systems with uncertainties under state constraints, namely, the terminal approach problem and the terminal evasion one. Such problems arise in systems with two controls, where the aim of the first is to steer the trajectory onto a given terminal set at a given instant without violating the state constraints, the aim of the other is opposite. It is assumed that the terminal set is a parallelepiped, the controls are bounded by parallelotope-valued constraints, and the state constraints are given in the form of so-called zones. We present techniques for solving both problems basing on polyhedral (parallelotope-valued or parallelepiped-valued) tubes. The techniques for solving the approach problem were proposed by the author earlier, but here additional properties of them are investigated. In particular, for the case without state constraints, guaranteed estimates are found for the trajectory that ensure that it is inside the tube. Convenient sufficient conditions are given to guarantee the obtaining of nondegenerate cross-sections during the calculations. For the evasion problem, a common solution scheme is considered, and then polyhedral techniques are proposed. The whole parametric families of external and internal polyhedral estimates for the solvability tubes for both problems are presented and compared. An illustrative example is given.