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In this paper, a wireless system is considered impacted by Beaulieu-Xie (BX) fading and Rician co-channel interference (CCI). A selection diversity combining technique is used to combat multi-path fading and CCI effects. The expression for the level crossing rate (LCR) is formulated for the receiver with more input branches, and the corresponding curves that have dependence on the signal-to-interference ratio (SIR) are drawn. On the basis of the presented graphs, we quantify the amount of LCR affected by the presence of fading and interference. Additionally, we propose a classification-based predictive model which leverages the previously calculated LCR value as one of inputs among other variables (number of users, base station, the day of the week) with the aim of Quality of Service (QoS) level prediction.

After a brief introduction highlighting the challenges of fluorine chemistry and the latest developments in the field, this Perspective will discuss how a combination of fluorine and fluorous chemistry together with fluorinated reagents helped to bridge between organic, molecular, macromolecular, supramolecular and biological sciences to create functions in the laboratory of the corresponding author. The reactivity of fluoride as a leaving group is best illustrated by SNAr reactions when it helped to demonstrate single electron transfer-mediated side reactions and through molecular design replaced activated aryl fluorides with aryl chlorides in the synthesis of poly(etherketone)s. Subsequently it was demonstrated how Ni(II) sigma complexes provided an orthogonal approach to the Suzuki-type cross-coupling of arylfluorides, other halides and all aryl C–O based electrophiles. Fluorinated reagents facilitated cylotrimetrization vs cyclotetramerization of bis(methoxy)benzyl chloride and alcohol and the synthesis of the simplest molecular liquid crystals. Triflic acid, methyl triflate facilitated the most tolerant living polymerizations including of cyclic siloxanes, functional vinyl ethers and oxazolines to generate self-organizable dendronized polymers while fluorine, trifluoromethyl and trifluoromethoxy groups facilitated disassembly and reassembly of liquid crystal polyethers and poly(p-phenylenes). Fluorinated stereocenters accessed the first heterochiral recognition in side-chain liquid crystal poly(vinyl ether)s and their model compounds. Alkali metal triflates mediated self-organization of supramolecular nonfluorinated and fluorinated self-assembling minidendrons, dendrons, dendrimers and self-organizable dendronized polymers. The role of fluorinated alkyl groups and of alkali metal triflates in the self-assembly, disassembly and isomorphic replacement analysis, of supramolecular helical columns, of the assembly of helical cogwheel coat and of spherical supramolecular dendrimers forming Frank-Kasper periodic and quasiperiodic arrays was highlighted. A brief discussion of fluorinated amino acids, peptides and peptoids and their potential role in the self-assembly and functions resulted from dendritic dipeptides followed by a discussion of semifluorinated amphiphilic Janus dendrimers as models of biological membranes, including for cell fusion and fission, concludes this Perspective.

Cu(0)-catalyzed single-electron transfer-living radical polymerization (SET-LRP) has shown great potential for applications in which well-defined chain end-functionalized polymers are demanded as final products or as intermediates. However, the use of polar reaction media favoring the disproportionation of Cu(I)X species into Cu(0) and Cu(II)X2 was considered a limiting factor specially in the synthesis of complex hydrophobic polymers with functional chain ends. “Self-generated” biphasic systems, in which the polymer phase-separates from the homogeneous reaction mixture above a certain molecular weight, together with fundamental studies on the role of solvent, including catalytic solvent effect, and methodological developments such us the “mixed-ligand” concept served as inspiration, although sometimes in an unknown way, to solve this problem. Today, SET-LRP of both acrylic and methacrylic vinyl monomers is already feasible in both polar and non-polar non-disproportionating solvents using their corresponding bi(multi)phasic “programmed” mixtures with water. Under these conditions, SET-LRP is an interfacial process in which disproportionation and activation events occur independently in the aqueous and organic compartments, and the “self-controlled” reversible deactivation takes place at the interface. Consequently, this design entirely defeats the limiting requirement to exclusively use disproportionating solvents. After a brief discussion of the historical evolution of the field of LRP, starting with the landmark work of Otsu from 1950th, this feature article will describe the elaboration of “programmed” bi(multi)phasic SET-LRP systems starting from initial inspiration to development in laboratory large-scale experiments.

Vehicular communications allow vehicles to connect with other vehicles and network infrastructures in order to facilitate the transfer of real-time information and dependable transportation. This paper proposes a system that connects vehicles to the network (base station) in two phases using transceivers-equipped roadside infrastructures, such as signboards, traffic lights, and street lights, as intermediary relay nodes. In the first phase, the information transfer occurs from vehicles to infrastructure using a radio-frequency (RF) link. The second phase includes establishing communication from the infrastructure to the base station using hybrid free-space optics (FSO)/RF link. In modeling the FSO link, we consider factors like atmospheric attenuation, pointing errors, and atmospheric turbulence-induced fading, which can affect FSO performance. For this set-up, we derive the accurate expressions for the outage probability, system throughput, average symbol error rate, and average end-to-end delay. Numerical results corroborate the dependency of the time allocation factor $\alpha$ for the vehicle-to-infrastructure link on the vehicle transmit power. Furthermore, the results elucidate the impact of the length of the transmitted packet and FSO link distance on average end-to-end delay performance. The increase in distance between infrastructure and base station can be compensated by reducing the length of packets to achieve desirable delay performance.

Despite more than a decade of active study, tuberculosis (TB) remains a serious health concern across the world, and it is still the biggest cause of mortality in the human population. Pathogenic bacteria recognize host-induced responses and adapt to those hostile circumstances. This high level of adaptability necessitates a strong regulation of bacterial metabolic characteristics. Furthermore, the immune reponse of the host virulence factors such as host invasion, colonization, and survival must be properly coordinated by the pathogen. This can only be accomplished by close synchronization of gene expression. Understanding the molecular characteristics of mycobacterial pathogenesis in order to discover therapies that prevent or resolve illness relies on the bacterial capacity to adjust its metabolism and replication in response to various environmental cues as necessary. An extensive literature details the transcriptional alterations of host in response to in vitro environmental stressors, macrophage infection, and human illness. Various studies have recently revealed the finding of several microRNAs (miRNAs) that are believed to play an important role in the regulatory networks responsible for adaptability and virulence in Mycobacterium tuberculosis. We highlighted the growing data on the existence and quantity of several forms of miRNAs in the pathogenesis of M. tuberculosis, considered their possible relevance to disease etiology, and discussed how the miRNA-based signaling pathways regulate bacterial virulence factors.

Primary structure endows tertiary structure while tertiary structure determines function. This fundamental principle is responsible for the generation of high order and precise functions in both biological assemblies including giant and mega proteins and nucleic acids as well as in metals generated from only few atoms. However, this size-independent ability to generate high order and very precise functions is not yet accessible in non-biological assemblies that use the same principles for their hierarchical self-organization. Here we report a study investigating the role of the molecular parameters on the hierarchical self-organizations of helical columnar assemblies produced from the column-forming self-assembling dendron (4-3,4-3,5)-X with a linear or branched hydrogenated or linear semifluorinated alkyl groups while apex is -CO2CH3 or -CH2OH. A combination of differential scanning calorimetry, small and wide-angle powder and oriented fiber X-ray diffraction experiments together with helical diffraction theory, 2-D and 3-D electron density maps were employed in these structural analysis experiments. They demonstrated that H-bonding at the apex of the self-assembling dendron enhanced the order of the helical columns by comparison with the order of supramolecular helical columns based on dendrons containing an ester group at their apex. This was the case for both linear and branched alkyl groups at the periphery of the self-assembling dendron. Unexpectedly, self-assembling dendrons containing semifluorinated alkyl groups on their periphery and H-bonding groups at their apex increase even more the order of their supramolecular perfluorinated porous helical column. In all cases helix is mediated by the aromatic part of the dendron but hierarchically influenced both by the apex and peripheral groups. A combination of branched alkyl groups with H-bonding at the apex produced a new mechanism to transform helical columns assembled from the column-forming (4-3,4-3,5)-X self-assembling dendron into spherical assemblies, organized from conical dendron conformers, forming an A15 Frank-Kasper phase.

Viral and synthetic vectors to deliver nucleic acids were key to the rapid development of extraordinarily efficient COVID-19 vaccines. The four-component lipid nanoparticles (LNPs), containing phospholipids, PEG-conjugated lipids, cholesterol, and ionizable lipids, co-assembled with mRNA via a microfluidic technology, are the leading nonviral delivery vector used by BioNTech/Pfizer and Moderna to access COVID-19 mRNA vaccines. LNPs exhibit a statistical distribution of their four components when delivering mRNA. Here, we report a methodology that involves screening libraries to discover the molecular design principles required to realize organ-targeted mRNA delivery and mediate activity with a one-component ionizable multifunctional amphiphilic Janus dendrimer (IAJD) derived from plant phenolic acids. IAJDs co-assemble with mRNA into monodisperse dendrimersome nanoparticles (DNPs) with predictable dimensions, via the simple injection of their ethanol solution in a buffer. The precise location of the functional groups in one-component IAJDs demonstrated that the targeted organs, including the liver, spleen, lymph nodes, and lung, are selected based on the hydrophilic region, while activity is associated with the hydrophobic domain of IAJDs. These principles, and a mechanistic hypothesis to explain activity, simplify the synthesis of IAJDs, the assembly of DNPs, handling, and storage of vaccines, and reduce price, despite employing renewable plant starting materials. Using simple molecular design principles will lead to increased accessibility to a large diversity of mRNA-based vaccines and nanotherapeutics.

Introduction: Upper limb arterial access is being increasingly used for coronary diagnostic and intervention procedures. Radial artery access is associated with reduced morbidity and mortality as compared to femoral artery access. However, access to the radial artery is not always successful with reported crossover rates to other routes between 3% and 8%. Ulnar artery access is emerging an attractive option both as upfront access and rescue access in case of failure to obtain radial artery access. Aims -: To assess and document the feasibility and safety of ulnar access as a default strategy. Methods: 2654 patients planned for coronary diagnostic and intervention procedureswere assessed for inclusion. Inclusion criteria were, all patients planned for coronary angiography (CAG) or percutaneous coronary intervention (PCI) with palpable ulnar pulse. Exclusion criteria included reverse Barbeau test type D, previous procedure resulting in radial artery occlusion/excision, hemodialysis patients having ipsilateral AV fistula and severe forearm deformities. Results: 2525 patients were found eligible, out of which 2495 (98.81%) were successfully cannulated. Procedure was completed in 2414 patients. Local site bleeding in 40 (1.6%) and acute loss of ulnar pulse noted in 33 (1.3%) out of 2495 patients. None of the patients had gangrene of access site, pseudo-aneurysm, arteriovenous fistula or neurological deficit post procedure. Conclusion: The Ulnar artery access as a default access is safe and feasible option for patient undergoing coronary diagnostic and interventional procedures.

Epithelial to mesenchymal transition transcription factors (EMT-TFs) such as SNAI2 have been found to be expressed endogenously in epidermal stem and progenitor cells and downregulated upon differentiation. The presence of SNAI2 in progenitor cells is necessary to repress the expression of differentiation genes by binding directly to their promoters. SNAI2 is downregulated upon differentiation which allows expression of differentiation genes. Furthermore overexpression of SNAI2 can block the differentiation process suggesting that the levels of SNAI2 are crucial to epidermal cell fate decisions. To address on a genome wide level the genes that are impacted by changing the levels of SNAI2, we performed microarray analysis on SNAI2 knockdown and overexpressing epidermal progenitor cells. Here we provide a detailed methods and analysis on these microarray data which has been deposited in Gene Expression Omnibus (GEO): GSE55269.

Cell fate commitment during development is achieved through the expression of lineage-specific transcription factors. Recent studies have suggested that the expression of combinations of these lineage-specific transcription factors can convert adult somatic cells from one type to another. Here we report that the combination of p63, a master regulator of epidermal development and differentiation, and KLF4, a regulator of epidermal differentiation, is sufficient to convert dermal fibroblasts to a keratinocyte phenotype. Induced keratinocytes (KCs) expressed KC-specific proteins and had a transcriptome similar to KCs. Reprogramming to a KC phenotype was rapid and efficient with a vast majority of cells morphologically resembling and expressing KC-specific genes within a week of p63 and KLF4 transduction. Furthermore, p63 and KLF4 are capable of inducing a KC phenotype even in a cancerous cell line, highlighting their importance for epidermal specification. The robustness of the conversion process also allows the use of this as a model system to study the mechanisms of reprogramming.

Novel 8-Benzyloxy-5-[2-(substituted-phenyl)-thiazol-4-yl]-1H-quinolin-2-one derivatives are synthesized by the cyclocondensation of substituted thiobenzamide and in-situ generated 8-benzyloxy-5-(2-bromo-acetyl)-1H-quinolin-2-one in the ethanol using simple one-pot multicomponent protocol under catalyst-free reaction conditions. All the products were screened for anti-tuberculosis (TB) activity against Mycobacterium tuberculosis H37Rv stains using L. J. medium conventional method and Compound 4h show good and Compound 4a, 4c, 4e, 4g, 4i, and 4j are also showing significant activity against M. tuberculosis. [ABSTRACT FROM AUTHOR]