Lebanese German University

Novel high symmetrical body centered carbon allotropes: cubic C48 and tetragonal C32 are proposed with respective original “ana” and “ukc” topologies. Devised from crystal structure engineering, their ground state structures and energy derived physical properties were accurately derived from quantum mechanics calculations within the density functional theory DFT. Both allotropes made of distorted tetrahedral C4 arrangements were found dense with ρ > 3 g/cm3 that remains lower than diamond density: ρ = 3.55 g/cm3. With cohesive albeit metastable ground state structures versus diamond, both allotropes show stability from the mechanical (elastic properties), dynamic (phonons band structures), as well as thermodynamic properties that show relationship with diamond’s experimental CV = f(T) discrete results. Vickers hardness magnitudes HV(C48) = 47 GPa and HV(C32) = 59 GPa indicate super-hard materials. The electronic band structures range from large direct band gap ∼5 eV for C48 to indirect band gap ~2.5 eV of semi-conducting-like C32. Such findings of original allotropes with targeted physical properties are bound to enrich the field of research on carbon allotropes especially highly symmetrical ones.

Novel orthorhombic carbon allotropes with original topologies: 44T39 C12, mog-C12 and cbs-C16 were devised from crystal structure rationale of C4 tetrahedra stacking and connections backed by density functional theory DFT-based calculations of ground state structures and energy derived physical properties. Specifically, the structures were identified with distorted C4 tetrahedra versus perfect tetrahedra characterizing diamond, accompanied by small atom-averaged volumes resulting into high densities and subsequent ultra hard mechanical behaviors. Dynamically, the allotropes were found stable with positive frequencies revealed from their phonons represented in band structures. Pertaining thermodynamic properties showed specific heat CV = f(T) calculated curves close to diamond’s experimental values from literature. The closest agreement with experiment was found for the most cohesive allotrope in the series, cbs-C16, concomitantly with the largest electronic indirect band gap, like diamond. From the investigation, a holistic interrelationship: “crystal structure ↔ mechanical ↔ dynamic ↔ electronic properties” is deducted for carbon materials.

Two novel superdense carbon allotropes, orthorhombic C12 with 44T39 and dia topologies, belonging to the same space group Pna21 (No. 33), have been predicted from crystal structure engineering and DFT-based calculations of ground state structures and energy-derived properties. Both allotropes were found to be cohesive and mechanically stable with positive sets of elastic constants. The phonon band structures confirm that they are also dynamically stable. The Vickers hardness evaluated by various models qualifies both allotropes as ultrahard with HV values equal to (or in the case of 44T39 C12, even higher than) that of diamond. While the new allotropes are metastable compared to diamond, their formation is possible at high pressures and high temperatures as a result of alternative metastable behavior. The electronic band structures indicate a transition from a semiconducting to an insulating state.

A novel carbon allotrope, hexagonal C8, is proposed from crystal chemistry and quantum density functional theory (DFT) investigations of the ground state structures and pertaining physical properties. The structure possessing an unknown topology with 3,42-c net exhibits corner sharing tetrahedra connected by cyclopropane-like C3. C8 was subsequently used as a template to devise original binary subnitride C6N2. Both the allotrope and the binary phase were found cohesive and stable mechanically (elastic constants and their combinations) and dynamically (phonons band structures) whilst presenting large hardness: HV(C8) = 60 GPa, and HV(C6N2) = 49 GPa. The electronic band structure reveals conductive behavior for the allotrope and insulating one for C6N2 with Egap ∼ 3 eV.

Digital medical instruments are essential in today's world to make fast and precise diagnoses. By combining several features into a single device, healthcare can be provided more affordably and with greater patient care and medical efficiency. This project describes the development of a cost-effective digital stethoscope featuring an integrated oximeter sensor and a sound transducer. The stethoscope facilitates the simultaneous monitoring of spO2 (Saturation of Peripheral Oxygen) levels and heart activity. The sound transducer converts cardiac sounds into electrical signals, enabling the detection of anomalies in heart function. Real-time data on these vital signs is transmitted to a web-application that will be deployed on the doctors' phone, providing them with immediate access to patient information. This innovative device offers a two in one solution that is both efficient and affordable for both patients and medical practitioners.

Novel superhard tetragonal carbon allotropes C5, C6, and C7, characterized by the presence of sp3- and sp2-like carbon sites, have been predicted from crystal chemistry and extensively studied by quantum density functional theory (DFT) calculations. All new allotropes were found to be cohesive, with crystal densities and cohesive energies decreasing along the C5 C6 C7 series due to the greater openness of the structures resulting from the presence of C=C ethene and C=C=C propadiene subunits, and mechanically stable with positive sets of elastic constants. The Vickers hardness evaluated by different models qualifies all allotropes as superhard. Phonon band structures confirm that the new allotropes are also dynamically stable. The electronic band structures reveal their metallic-like behavior due to the presence of sp2-hybridized carbon.

BackgroundAnemia of chronic disease is known to be associated with inflammation. However, the relationship between hemoglobin (Hb) levels and potential inflammatory markers such as neutrophil-to-lymphocyte ratio (NLR), monocyte-to-lymphocyte ratio (MLR), platelet-to-lymphocyte ratio (PLR), and mean platelet volume-to-platelet count ratio (MPV/PC) has not been extensively studied. The primary objective of this retrospective analytical study conducted at Al Zahraa Hospital University Medical Center (ZHUMC), Beirut, was to investigate the correlation between Hb levels and potential inflammatory markers (NLR, MLR, PLR, MPV/PC) in patients visiting the emergency department (ED), across different genders and age groups. The secondary objectives were to compare Hb levels and inflammatory markers values between the referred medical ward group (the hospitalized patients who were admitted to the medical ward), and the non-referred to medical ward group (the patients who were discharged home from the ED), and to evaluate the predictability of inflammatory markers and Hb levels for referral to the medical ward, including the determination of optimal cutoff values for hospital admission to the medical ward.MethodsWe analyzed the blood parameters of 379 adult patients who presented to the ED with various medical complaints between September 1, 2022, and November 30, 2022 (three months). These patients were included in the study after we checked their eligibility regarding the verification of all our inclusion and exclusion criteria.ResultsOur findings revealed a significant negative correlation between Hb levels and PLR (r = -0.24) in both genders and across different age groups. The group referred to the medical ward exhibited lower Hb levels and higher NLR, MLR, and PLR values (P < 0.001). NLR/Hb ratio emerged as a predictive factor for admission in genitourinary (R² = 0.158; OR = 5.62) and respiratory groups (R² = 0.206; OR = 5.89), with specific cutoff values of 0.533 (Sensitivity = 57.1% & Specificity = 84.2%) and 0.276 (Sensitivity = 85% & Specificity = 51.1%), respectively.ConclusionsOur study demonstrates that hemoglobin level negatively correlates with PLR. NLR, MLR, and PLR stand as important inflammatory markers. Moreover, we present the first study in the literature to show that NLR/Hb ratio can serve as a predictor for referral to the medical ward, particularly in the genitourinary and respiratory patient groups, underscoring its value in risk assessment as a prognostic marker reflecting the need for admission when the case is more serious.

The objective of this research is to connect Arabic theoretical linguistics with modern linguistics, not by disregarding the present and attributing the later theories solely to Arab grammarians and rhetoricians, as has often been assumed. Rather, this research aims to qualitatively explore the linguistic accomplishments of ancient Arab scholars from a contemporary perspective and identify commonalities and controversies between past and present perspectives. Specifically, this study focuses on Sibawayh's interpretation of functional linguistics and its final formulation by Jakobson. Additionally, the study aims to analyse and compare the principles of language and grammar advocated by ancient Arab linguists and contemporary linguists to deepen our understanding of language and its role in human society. The results of this study reveal that while Sibawayh concentrated on the analysis of structure and function in Arabic grammar, modern linguists such as Jakobson have broadened their approach to include a wider range of perspectives including sociolinguistics, psycholinguistics, and neurolinguistics. Therefore, it is essential to acknowledge the contributions of Sibawayh as his work formed the foundation for language theories in general and linguistics in particular.