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Vertical Take-Off and Landing (VTOL) based Unmanned Aerial Vehicles (UAV) allow quick, safe, and effective transit of resources from one place to another. Its primary objective is to complete its mission in a short time, thus, making it more useful during emergency cases such as road accidents. A novel design for VTOP UAVs has been proposed in this paper. A mobile application has been created to send and receive commands. The cost estimation and analysis have been carried out for the development and deployment of this device in a real-life scenario. VTOL Unmanned Aerial Vehicles are a novel design for the transportation of medical supplies that aim to significantly increase the flight range and endurance compared to conventional aircraft rotorcraft configurations. The overall conceptual design, modelling and computational simulation of this design are presented.

Many nanodevices and quantum devices, with their sizes often spanning from millimeters down to sub-nanometer, have intricate low-dimensional, non-uniform, or hierarchical structures on surfaces and interfaces. Since their functionalities are dependent on these structures, high-resolution surface-sensitive characterization becomes imperative to gain a comprehensive understanding of the function–structure relationship. We thus developed hard x-ray ptychographic reflectometry imaging, a new technique that merges the high-resolution two-dimensional imaging capabilities of hard x-ray ptychography for extended objects, with the high-resolution depth profiling capabilities of x-ray reflectivity for layered structures. The synergy of these two methods fully leverages both amplitude and phase information from ptychography reconstruction to not only reveal surface topography and localized structures, such as shapes and electron densities, but also yields statistical details, such as interfacial roughness that is not readily accessible through coherent imaging solely. The hard x-ray ptychographic reflectometry imaging is well-suited for three-dimensional imaging of mesoscopic samples, particularly those comprising planar or layered nanostructures on opaque supports, and could also offer a high-resolution surface metrology and defect analysis on semiconductor devices, such as integrated nanocircuits and lithographic photomasks for microchip fabrications. [ABSTRACT FROM AUTHOR]

Multiple theories exist to explain cancer initiation, although a consensus on this is crucial for developing effective therapies. 'Somatic mutation theory' suggests that mutations in somatic cells during DNA repair initiates cancer but this concept has several attached paradoxes. Research efforts to identify quiescent cancer stem cells (CSCs) that survive therapy and result in metastasis and recurrence have remained futile. In solid cancers, CSCs are suggested to appear during epithelial-mesenchymal transition by the dedifferentiation and reprogramming of epithelial cells. Pluripotent and quiescent very small embryonic-like stem cells (VSELs) exist in multiple tissues but remain elusive owing to their small size and scarce nature. VSELs are developmentally connected to primordial germ cells, undergo rare, asymmetrical cell divisions and are responsible for the regular turnover of cells to maintain tissue homeostasis throughout life. VSELs are directly vulnerable to extrinsic endocrine insults because they express gonadal and gonadotropin hormone receptors. VSELs undergo epigenetic changes due to endocrine insults and transform into CSCs. CSCs exhibit genomic instability and develop mutations due to errors during DNA replication while undergoing excessive proliferation and clonal expansion to form spheroids. Thus tissue-resident VSELs offer a connection between extrinsic insults and variations in cancer incidence reported in various body tissues. To conclude, cancer is indeed a stem cell disease with mutations occurring as a consequence. In addition to immunotherapy, targeting mutations, and Lgr5 + organoids for developing new therapeutics, targeting CSCs (epigenetically altered VSELs) by improving their niche and epigenetic status could serve as a promising strategy to treat cancer. [ABSTRACT FROM AUTHOR]

Joint sealing in jointed plain concrete pavement (JPCP) has been practiced throughout the world for many years as it improves the performance of concrete pavements. The infiltration of water is a common problem in concrete pavements and often increases distresses, such as faulting and pumping. For this reason, sealing the joints can help reduce water infiltration. Additionally, the infiltration of sand and small stones, aggregates, or debris into the joints can also be prevented, consequently reducing joint spalling in concrete pavements. However, it is also reported that joint sealing increases the initial cost of construction, especially if the joints need to be resealed, which leads to some additional costs. In this study, the pavement distress data was collected from the long-term pavement performance (LTPP) database for all the JPCPs sections in North Texas. The study illustrates the relative field performance in terms of spalling, faulting, roughness, and deflections of JPCP sections for both sealed and unsealed LTPP sections of North Texas. Key words: jointed plain concrete pavement (JPCP), joint sealing, spalling, faulting, roughness, deflection. Le remplissage des joints de chaussee en beton uni (CBU) est pratique dans le monde entier depuis de nombreuses annees, car il ameliore la tenue des chaussees en beton. L'infiltration d'eau est un probleme frequent que subissent les chaussees en beton et qui cause souvent le developpement de degradations, comme les defaillances et le pompage. Pour cette raison, assurer l'etancheite des joints peut aider a reduire l'infiltration d'eau. De plus, l'infiltration de sable et de petites pierres, de granulats ou de debris dans les joints peut egalement etre evitee, reduisant en consequence l'epaufrure des joints de chaussee en beton. Cependant, il est egalement signale que le remplissage des joints augmente le cout initial de la construction, surtout si les joints doivent etre remplis a nouveau, ce qui entraine des couts supplementaires. Dans cette etude, les donnees sur la degradation des chaussees ont ete recueillies a partir de la base de donnees de la <> (LTPP) pour toutes les sections des CBU du nord du Texas. L'etude illustre la tenue relative sur le terrain compte tenu de l'epaufrure, de la defaillance, de la rugosite et de la deflexion des sections de CBU pour les sections scellees et non scellees de la LTPP du nord du Texas. [Traduit par la Redaction] Mots-cles: chaussee en beton uni (CBU), remplissage, epaufrure, defaillance, rugosite, deflexion., Introduction Transverse joints are designed and constructed in jointed plain concrete pavements (JPCP) to allow slab expansion and contraction, which minimizes cracking. Joints are constructed by sawing to a partial [...]