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There is a compelling reason to design cost-effective sensors to detect and measure harmful molecules such as dichlorosilane ($\mathrm{H}_{2}\mathrm{SiCl}_{2}$) in the air. In this work, density functional theory (DFT) has been used to study the nature of the intermolecular interactions between the $\mathrm{H}_{2}\mathrm{SiCl}_{2}$ gas molecule with a single-walled pristine, Al-doped, and Ga-doped boron nitride nanotubes (BNNT, BNAlNT, and BNGaNT, respectively) to investigate their potential in gas-sensing applications. Full-dimensional geometry optimization and adsorption energies were calculated with four functionals: PBE0, M06-2X, ${\omega }$B97XD, and B3LYP-D3 with a 6-311G(d) basis set. We find that the B, Al, or Ga atoms provide the most favorable sites for adsorption of the $\mathrm{H}_{2}\mathrm{SiCl}_{2}$ molecule. The adsorbate is more tightly bound to the surface of the doped rather than of the pristine BNNT nanotubes, demonstrating a larger energy gain due to adsorption. This is due to the fact that $\mathrm{H}_{2}\mathrm{SiCl}_{2}$ interacts with pristine BNNT through weak Van der Waals forces but seemingly has stronger ionic interactions with the doped variants. In general, introducing impurities can improve the selectivity and reactivity of the BNNT toward $\mathrm{H}_{2}\mathrm{SiCl}_{2}$. Among all of the absorbents, we find that BNGaNT exhibits the highest affinity toward $\mathrm{H}_{2}\mathrm{SiCl}_{2}$, and therefore holds a higher potential compared to the rest of the nanotubes investigated here for designing materials for dichlorosilane sensors.

Direct Metal Deposition (DMD) is one of the underwater marine additive manufacturing (MAM) technologies known for its capability to build up on semi-finished products. This allows for the creation of complex structures and repair the damaged or worn-out areas. Employing this underwater technology needs a lot of consideration regarding the harsh environment of the ocean. This research endeavours to identify nickel-aluminium bronze’s structural characteristics printed underwater. Simulation studies can help to analyse grain and phase evolution, defects, and melt pool behaviour, enabling the optimization of printing parameters for high-quality marine alloy components. To achieve that a control systems and machine learning algorithms need to developed to enhance precision in the 3D printing process on a moving platform, addressing the challenges of six distinct vessel movements at sea. This integration aims to improve accuracy, contributing to optimal performance in dynamic maritime environments.

Background: Pott's Puffy tumor (PPT) is a complicated frontal sinusitis that is also described as frontal bone osteomyelitis and a localized sub periosteal abscess. Early diagnosis and immediate active treatment are necessary to prevent severe neurologic sequelae. Case Presentation: Here, we report on a case of Pott's puffy tumor in a previously healthy 13-year-old girl with a worsening headache and swelling of the frontal bone accompanied by vomiting and fever. Magnetic resonance imaging revealed osteomyelitis of the frontal bone. A foreign body was discovered and removed via endoscopy which was then followed by 6 weeks of parenteral and enteral antibiotic therapy, resulting in resolution of all symptoms. Conclusion: A complete history in terms of trauma and insect bite or foreign body in the nose is paramount for a correct diagnosis, and performing a full examination of ear, nose and throat (ENT) to rule out a foreign body is advised. [ABSTRACT FROM AUTHOR]

In this paper, we have theoretically determined the possibility of adsorption of the gaseous C[H.sub.2][N.sub.2] molecule on the surface of [X.sub.12][Y.sub.12] nanocages, where X = B, Al, Ga and Y = N, P, As. The electronic structure calculations have been performed by density functional theory (DFT) using four functionals (i.e., B3LYP-D3, M06-2X, [omega]B97XD, and CAM-B3LYP), together with the 6-311G(d) basis function. We find that the adsorption of C[H.sub.2][N.sub.2] on top of the X-Y bond of the nanocage is the most preferred site for adsorption. The adsorption process is accompanied by a charge-transfer phenomenon, which results in a strong bond between the terminal N atom of diazomethane and the X atom of the nanocage. This gives rise to significant changes in the highest and lowest occupied molecular orbital (HOMO and LUMO, respectively) energies and thus attribute properties to the nanocages that enable them to act as building blocks of C[H.sub.2][N.sub.2] sensing materials. Key words: diazomethane, nanocage, DFT, NBO, QTAIM. Dans le cadre des présents travaux, nous avons réalisé une étude théorique pour déterminer la possibilité d'adsorption de la molécule de diazométhane (C[H.sub.2][N.sub.2]) gazeux à la surface de nanocages de formule [X.sub.12][Y.sub.12], où X = B, Al, Ga et Y = N, P, As. Nous avons modélisé la structure électronique selon des calculs de la théorie de la fonctionnelle de la densité (DFT), dans lesquels nous avons utilisé quatre fonctionnelles (soit B3LYPD3, M062X, xB97XD et CAMB3LYP) ainsi que la base 6311G(d). Nos résultats montrent que la liaison X-Y de la nanocage est le site d'adsorption privilégié du C[H.sub.2][N.sub.2]. Le processus d'adsorption est accompagné d'un phénomène de transfert de charge, qui se traduit par une forte liaison entre l'atome d'azote terminal du diazométhane et l'atome X de la nanocage. Ce phénomène donne lieu à des changements importants dans les énergies des orbitales moléculaires frontières (HOMO et LUMO) et confère donc aux nanocages des propriétés qui en font d'éventuels constituants de base pour former des matériaux de détection du C[H.sub.2][N.sub.2]. [Traduit par la Rédaction] Mots-clés : diazomethane, nanocage, théorie de la fonctionnelle de la densité, orbitales naturelles de liaison, théorie quantique des atomes dans les molecules., 1. Introduction Diazomethane (C[H.sub.2][N.sub.2])--ahighly toxic, flammable, and corrosive gas in its pure form at room temperature--can have a number of severe effects upon human health. (1) For example, inhalation of [...]