Miracle-dz/UniFAR-FTUs huggingface dataset:
RF Power Amplifier Efficiency Improvement under Antenna Impedance Variation Using a Tunable Matching Network

The antenna input impedance is commonly assumed to be constant but in a real scenario, the impedance value is affected by the environment. This impedance variation affects the performance of the RF power amplifier and its parameters: stability, output power, linearity and efficiency. Among the methods that can mitigate the effects of impedance variation to impedance performance, the tunable matching network (TMN) was used because this technique provides the direct compensation by re-matching the mismatched impedance. A power amplifier was designed first in order to observe the variation of its performance with respect to load impedances which have a VSWR value of less than or equal to four and resulted a PAE variation from 35% to 68%. There was a reduction of 10 percent to the highest achievable PAE mainly due to the loss contributed by the varactors use in the TMN. An improvement up to 10 percent is also seen in various loads especially those near the edge of the VSWR = 4 after integrating the TMN. In addition, the lowest possible output power due to impedance variation was increased from 36 dBm to 38 dBm after integrating the TMN. Another set of simulations was done using ideal varactors in the TMN and resulted to a variation in PAE from 65% to 69% with the lowest output power level of 39.4 dBm recorded.
A Communication Architecture for Cooperative Networked Cyber-Physical Systems

Cyber-Physical Systems (CPSs) are used in various important application areas. Networking of several CPSs, the internal networking of CPSs components as well as the interconnection with other systems, is of major importance with respect to scientific, engineering and technical considerations; yet, it is also very challenging. In this paper we describe an architecture and methods which can be used for various networked CPSs. To base the system design and approaches on realistic requirements and devise suitable methods, we use tightly cooperating, mobile robots as application area. This is an example of challenging CPSs which put high demands on the networking methods. Nevertheless, the considerations are applicable to other CPSs as well. In order to enable networked mobile robots to perform individual and cooperative tasks, real-time support and network operations such as merge, split, and synchronize among clusters of such robots are needed. Further, management functions have to be provided which enable independent, but concurrent clusters to allocate and share scarce network resources. In the context of this paper, network resources are considered in a broad sense (e.g., time slots, frequency channels, codes) and assigned by a novel scheduling algorithm. Thus, a schedule means not only a sequence of time slots, but it takes all mentioned dimensions into account.
Underwater Image Enhancement Algorithm Based on Logarithmic Transform Histogram Matching With Spatial Equalization

In this paper a novel algorithm is proposed for underwater image enhancement. The proposed method based on combined local and global image processing in the frequency domain. The basic idea is to apply logarithmic transform histogram matching with spatial equalization approach on different image blocks. The resulting image is a weighted mean of all processing blocks driven through optimization of measure of enhancement (EME). Some presented experimental results illustrate the performance of the proposed algorithm on real underwater images in comparison with the classical contrast enhancement techniques and adaptive histogram equalization techniques.
A Novel Receiver Technique to enable NOMA Without User Selection

NOMA (Non Orthogonal Multiple Access)/MUST (Multi-User Superposition Transmission) is one of the major candidates for next generation wireless access technologies as they provide better user fairness and improved spectral efficiency. Successive Interference Cancellation (SIC) receivers enable multiple users to be scheduled in the same time-frequency resources while differentiated in power domain. Two user Power Domain NOMA (PD-NOMA) analysis clearly shows that the SNR difference between the users is very important in order to achieve inter-user interference cancellation. Hence user selection or pairing becomes crucial and can lead to heavy co-channel interference when users are paired wrongly. In order to overcome this problem, a new method of NOMA is proposed where the user pairing can be arbitrary, but an advanced receiver technique is used which enables successful decoding of the desired user’s data. A novel Gaussian Mixture based receiver is proposed. It is shown that the error rate performance of this detector is very close to that of a joint detector and the proposed technique can be used both in uplink and downlink directions. Another key contribution of this work is to show the over-modeling technique which enables the decoder to operate without having to know any prior information about the interferers. This enables a practical approach to build Gaussian Mixture Model (GMM) based receivers for a variety of interference scenarios.
New Synthetic Cannabinoids Metabolism and Strategies to Best Identify Optimal Marker Metabolites

Synthetic cannabinoids (SCs) were initially developed as pharmacological tools to probe the endocannabinoid system and as novel pharmacotherapies, but are now highly abused. This is a serious public health and social problem throughout the world and it is highly challenging to identify which SC was consumed by the drug abusers, a necessary step to tie adverse health effects to the new drug's toxicity. Two intrinsic properties complicate SC identification, their often rapid and extensive metabolism, and their generally high potency relative to the natural psychoactive Δ9-tetrahydrocannabinol in cannabis. Additional challenges are the lack of reference standards for the major urinary metabolites needed for forensic verification, and the sometimes differing illicit and licit status and, in some cases, identical metabolites produced by closely related SC pairs, i.e., JWH-018/AM-2201, THJ-018/THJ-2201, and BB-22/MDMB-CHMICA/ADB-CHMICA. We review current SC prevalence, establish the necessity for SC metabolism investigation and contrast the advantages and disadvantages of multiple metabolic approaches. The human hepatocyte incubation model for determining a new SC's metabolism is highly recommended after comparison to human liver microsomes incubation, in silico prediction, rat in vivo, zebrafish, and fungus Cunninghamella elegans models. We evaluate SC metabolic patterns, and devise a practical strategy to select optimal urinary marker metabolites for SCs. New SCs are incubated first with human hepatocytes and major metabolites are then identified by high-resolution mass spectrometry. Although initially difficult to obtain, authentic human urine samples following the specified SC exposure are hydrolyzed and analyzed by high-resolution mass spectrometry to verify identified major metabolites. Since some SCs produce the same major urinary metabolites, documentation of the specific SC consumed may require identification of the SC parent itself in either blood or oral fluid. An encouraging trend is the recent reduction in the number of new SC introduced per year. With global collaboration and communication, we can improve education of the public about the toxicity of new SC and our response to their introduction.
Rewiring of Memory Circuits: Connecting Adult Newborn Neurons With the Help of Microglia

New neurons are continuously generated from stem cells and integrated into the adult hippocampal circuitry, contributing to memory function. Several environmental, cellular, and molecular factors regulate the formation of new neurons, but the mechanisms that govern their incorporation into memory circuits are less explored. Herein we will focus on microglia, the resident immune cells of the CNS, which modulate the production of new neurons in the adult hippocampus and are also well suited to participate in their circuit integration. Microglia may contribute to the refinement of brain circuits during development and exert a role in physiological and pathological conditions by regulating axonal and dendritic growth; promoting the formation, elimination, and relocation of synapses; modulating excitatory synaptic maturation; and participating in functional synaptic plasticity. Importantly, microglia are able to sense subtle changes in their environment and may use this information to differently modulate hippocampal wiring, ultimately impacting on memory function. Deciphering the role of microglia in hippocampal circuitry constant rewiring will help to better understand the influence of microglia on memory function.
How Viral and Intracellular Bacterial Pathogens Reprogram the Metabolism of Host Cells to Allow Their Intracellular Replication

Viruses and intracellular bacterial pathogens (IBPs) have in common the need of suitable host cells for efficient replication and proliferation during infection. In human infections, the cell types which both groups of pathogens are using as hosts are indeed quite similar and include phagocytic immune cells, especially monocytes/macrophages (MOs/MPs) and dendritic cells (DCs), as well as nonprofessional phagocytes, like epithelial cells, fibroblasts and endothelial cells. These terminally differentiated cells are normally in a metabolically quiescent state when they are encountered by these pathogens during infection. This metabolic state of the host cells does not meet the extensive need for nutrients required for efficient intracellular replication of viruses and especially IBPs which, in contrast to the viral pathogens, have to perform their own specific intracellular metabolism to survive and efficiently replicate in their host cell niches. For this goal, viruses and IBPs have to reprogram the host cell metabolism in a pathogen-specific manner to increase the supply of nutrients, energy, and metabolites which have to be provided to the pathogen to allow its replication. In viral infections, this appears to be often achieved by the interaction of specific viral factors with central metabolic regulators, including oncogenes and tumor suppressors, or by the introduction of virus-specific oncogenes. Less is so far known on the mechanisms leading to metabolic reprogramming of the host cell by IBPs. However, the still scant data suggest that similar mechanisms may also determine the reprogramming of the host cell metabolism in IBP infections. In this review, we summarize and compare the present knowledge on this important, yet still poorly understood aspect of pathogenesis of human viral and especially IBP infections.
Recent Advances on the Analysis of Polychrome Works of Art: SERS of Synthetic Colorants and Their Mixtures With Natural Dyes

The development and application of proper sample pretreatments is often a key step toward the successful analysis of dyes used as artists' materials by surface-enhanced Raman spectroscopy (SERS). Complexation of the organic colorants with metal ions to dye fabrics and produce lake pigments, as well as undesired interactions with other matrix components such as substrate, binding media, fillers, and extenders, are just some of the issues that typically complicate dye identification in minute samples from invaluable artworks and museum objects. These concerns may be addressed by using, prior to SERS analysis, ad-hoc sample pretreatments that, in addition to increasing the technique's sensitivity, favorably affect its selectivity toward certain molecules or molecular classes. The present work describes a newly developed sample pretreatment based on the use of nitric acid that has proven crucial for the successful detection of aniline and xanthene dyes–the first synthetic organic colorants to be used in printing and painting, among other art forms–in microscopic samples from works of art such as a 19th-century silk fabric, paper cut-outs by Henri Matisse, Vincent Van Gogh's Irises, and Japanese woodblock prints. This treatment promotes the hydrolysis of the dye-metal bond in mordant dyes or lake pigments, resulting in a more efficient adsorption of the dye molecules on the SERS-active substrate and, hence, enabling the acquisition of high-quality spectra. In the case of synthetic colorants, this method shows advantages over hydrolysis with hydrofluoric acid–a procedure previously established for the analysis of red lakes prepared from natural dyes. The nitric acid treatment presented here may be integrated into a multi-step methodology that, by exploiting differences in solubility of various dyes and lake pigments, has enabled for the first time to successfully characterize intentional mixtures of natural and synthetic colorants of the xanthene and anthraquinone molecular classes, i.e., eosin Y and carmine, in a selection of Japanese prints of the Meiji era. The present study paves the way for the systematic identification of synthetic dyes in objects of artistic and archeological interest, even when they are present in mixtures with natural organic colorants.
Structure and function of the immune system in the spleen

The spleen is a multitasking secondary lymphoid organ with specialized cells for initiating immunity to blood-borne targets. The spleen is the largest secondary lymphoid organ in the body and, as such, hosts a wide range of immunologic functions alongside its roles in hematopoiesis and red blood cell clearance. The physical organization of the spleen allows it to filter blood of pathogens and abnormal cells and facilitate low-probability interactions between antigen-presenting cells (APCs) and cognate lymphocytes. APCs specific to the spleen regulate the T and B cell response to these antigenic targets in the blood. This review will focus on cell types, cell organization, and immunologic functions specific to the spleen and how these affect initiation of adaptive immunity to systemic blood-borne antigens. Potential differences in structure and function between mouse and human spleen will also be discussed.
Regulation of predictive analytics in medicine

Algorithms must meet regulatory standards of clinical benefit Artificial intelligence (AI) and increased computing power have long held the promise of improving prediction and prognostication in health care (1). Now, use of predictive analytics and AI in medicine, though with fits and starts, is transitioning from hype to reality: Several commercial algorithms have received regulatory approval for broad clinical use. But the barrier for entry of new advanced algorithms has been low. To unlock the potential of advanced analytics while protecting patient safety, regulatory and professional bodies should ensure that advanced algorithms meet accepted standards of clinical benefit, just as they do for clinical therapeutics and predictive biomarkers. External validation and prospective testing of advanced algorithms are clearly needed (2), but recent regulatory clearances raise concerns over the rigor of this process. Given these concerns, we propose five standards to guide regulation of devices based on predictive analytics and AI. Although well-established research standards, such as the TRIPOD Checklist, exist for developing and validating multivariable prediction models in medicine (3), our standards provide regulatory guidance for such algorithms prior to implementation in clinical settings.
Hachimoji DNA and RNA: A genetic system with eight building blocks

Expanding the genetic code DNA and RNA are naturally composed of four nucleotide bases that form hydrogen bonds in order to pair. Hoshika et al. added an additional four synthetic nucleotides to produce an eight-letter genetic code and generate so-called hachimoji DNA. Coupled with an engineered T7 RNA polymerase, this expanded DNA alphabet could be transcribed into RNA. Thus, new forms of DNA that add information density to genetic biopolymers can be generated that may be useful for future synthetic biological applications. Science, this issue p. 884 DNA that includes synthetic bases expands the genetic code from four to eight nucleotide letters We report DNA- and RNA-like systems built from eight nucleotide “letters” (hence the name “hachimoji”) that form four orthogonal pairs. These synthetic systems meet the structural requirements needed to support Darwinian evolution, including a polyelectrolyte backbone, predictable thermodynamic stability, and stereoregular building blocks that fit a Schrödinger aperiodic crystal. Measured thermodynamic parameters predict the stability of hachimoji duplexes, allowing hachimoji DNA to increase the information density of natural terran DNA. Three crystal structures show that the synthetic building blocks do not perturb the aperiodic crystal seen in the DNA double helix. Hachimoji DNA was then transcribed to give hachimoji RNA in the form of a functioning fluorescent hachimoji aptamer. These results expand the scope of molecular structures that might support life, including life throughout the cosmos.
Compact radio emission indicates a structured jet was produced by a binary neutron star merger

Merging produced a structured jet The binary neutron star merger event GW170817 was observed with gravitational waves and across the electromagnetic spectrum. However, the physical processes that produced that emission remain poorly understood, particularly the late-time x-ray and radio emission. Ghirlanda et al. observed the radio afterglow with an interferometric array of 32 radio telescopes spread across the globe. The size and position of the radio source are not compatible with a uniformly expanding cocoon, as some have suggested. Instead, the data indicate that GW170817 produced a structured jet of material that escaped the surrounding ejecta and is now expanding into the interstellar medium at relativistic speeds. Science, this issue p. 968 The binary neutron star merger GW170817 produced a structured relativistic jet observed at radio wavelengths. The binary neutron star merger event GW170817 was detected through both electromagnetic radiation and gravitational waves. Its afterglow emission may have been produced by either a narrow relativistic jet or an isotropic outflow. High-spatial-resolution measurements of the source size and displacement can discriminate between these scenarios. We present very-long-baseline interferometry observations, performed 207.4 days after the merger by using a global network of 32 radio telescopes. The apparent source size is constrained to be smaller than 2.5 milli–arc seconds at the 90% confidence level. This excludes the isotropic outflow scenario, which would have produced a larger apparent size, indicating that GW170817 produced a structured relativistic jet. Our rate calculations show that at least 10% of neutron star mergers produce such a jet.
Disabling the Gβγ-SNARE interaction disrupts GPCR-mediated presynaptic inhibition, leading to physiological and behavioral phenotypes

Genetic ablation of Gβγ-SNARE signaling produces stress- and depression-related behaviors. Gβγ ensnares neurotransmitter vesicles The exocytosis of neurotransmitter-containing vesicles requires the SNARE protein complex to mediate vesicle fusion with the plasma membrane. The Gβγ subunit activated by Gi/o-coupled GPCRs can inhibit this process by interacting with the SNARE protein SNAP25. Zurawski et al. generated mice that expressed a mutant form of SNAP25 that could not interact with Gβγ. These mice showed defects in nociception, stress responses, motor coordination, affect, and spatial learning. These results provide in vivo evidence of the importance of the association between presynaptic Gβγ and SNARE proteins in presynaptically inhibiting neurotransmitter release. G protein–coupled receptors (GPCRs) that couple to Gi/o proteins modulate neurotransmission presynaptically by inhibiting exocytosis. Release of Gβγ subunits from activated G proteins decreases the activity of voltage-gated Ca2+ channels (VGCCs), decreasing excitability. A less understood Gβγ-mediated mechanism downstream of Ca2+ entry is the binding of Gβγ to SNARE complexes, which facilitate the fusion of vesicles with the cell plasma membrane in exocytosis. Here, we generated mice expressing a form of the SNARE protein SNAP25 with premature truncation of the C terminus and that were therefore partially deficient in this interaction. SNAP25Δ3 homozygote mice exhibited normal presynaptic inhibition by GABAB receptors, which inhibit VGCCs, but defective presynaptic inhibition by receptors that work directly on the SNARE complex, such as 5-hydroxytryptamine (serotonin) 5-HT1b receptors and adrenergic α2a receptors. Simultaneously stimulating receptors that act through both mechanisms showed synergistic inhibitory effects. SNAP25Δ3 homozygote mice had various behavioral phenotypes, including increased stress-induced hyperthermia, defective spatial learning, impaired gait, and supraspinal nociception. These data suggest that the inhibition of exocytosis by Gi/o-coupled GPCRs through the Gβγ-SNARE interaction is a crucial component of numerous physiological and behavioral processes.
U-Pb constraints on pulsed eruption of the Deccan Traps across the end-Cretaceous mass extinction

Two timelines for extinction The Cretaceous-Paleogene extinction that wiped out the nonavian dinosaurs 66 million years ago was correlated with two extreme events: The Chicxulub impact occurred at roughly the same time that massive amounts of lava were erupting from the Deccan Traps (see the Perspective by Burgess). Sprain et al. used argon-argon dating of the volcanic ash from the Deccan Traps to argue that a steady eruption of the flood basalts mostly occurred after the Chicxulub impact. Schoene et al. used uranium-lead dating of zircons from ash beds and concluded that four large magmatic pulses occurred during the flood basalt eruption, the first of which preceded the Chicxulub impact. Whatever the correct ordering of events, better constraints on the timing and rates of the eruption will help elucidate how volcanic gas influenced climate. Science, this issue p. 866, p. 862; see also p. 815 Large amounts of volcanism may have preceded the large impact associated with the demise of nonavian dinosaurs. Temporal correlation between some continental flood basalt eruptions and mass extinctions has been proposed to indicate causality, with eruptive volatile release driving environmental degradation and extinction. We tested this model for the Deccan Traps flood basalt province, which, along with the Chicxulub bolide impact, is implicated in the Cretaceous-Paleogene (K-Pg) extinction approximately 66 million years ago. We estimated Deccan eruption rates with uranium-lead (U-Pb) zircon geochronology and resolved four high-volume eruptive periods. According to this model, maximum eruption rates occurred before and after the K-Pg extinction, with one such pulse initiating tens of thousands of years prior to both the bolide impact and extinction. These findings support extinction models that incorporate both catastrophic events as drivers of environmental deterioration associated with the K-Pg extinction and its aftermath.