Miracle-dz/UniFAR-FTUs huggingface dataset:
Multi-Frequency Air-to-Ground Channel Measurements and Analysis for UAV Communication Systems

In order to implement unmanned aerial vehicle (UAV)-based wireless communications, a better understanding of wireless channels and the corresponding channel characterizations are critical. In this paper, air-to-ground (AG) channel measurements are carried out at some candidate frequencies, i.e., 1 GHz, 4 GHz, 12 GHz, and 24 GHz. With measurement data, the crucial channel parameters are comprehensively analyzed. Firstly, based on the channel model in the 3rd Generation Partnership Project (3GPP), the essential coefficients for modeling path loss, including path loss exponents (PLEs) and height-dependent factors, are obtained for AG channels. Then, a novel autocorrelation model for shadow fading is proposed. Besides, the small-scale fading is statistically analyzed, where the log-logistic distribution is found as the best fit among popular distributions. Moreover, the second-order statistical characteristics, including the level crossing rate (LCR) and average fade duration (AFD), are extracted to describe in-depth the fading behavior. Overall, the results and findings in this paper are essential for realizing reliable communications in AG wireless systems.
Small Molecule Inhibitors Confirm Ubiquitin-Dependent Removal of TOP2-DNA Covalent Complexes

DNA topoisomerase II (TOP2) is required for the unwinding and decatenation of DNA through the induction of an enzyme-linked double-strand break (DSB) in one DNA molecule and passage of another intact DNA duplex through the break. Anticancer drugs targeting TOP2 (TOP2 poisons) prevent religation of the DSB and stabilize a normally transient intermediate of the TOP2 reaction mechanism called the TOP2-DNA covalent complex. Subsequently, TOP2 remains covalently bound to each end of the enzyme-bridged DSB, which cannot be repaired until TOP2 is removed from the DNA. One removal mechanism involves the proteasomal degradation of the TOP2 protein, leading to the liberation of a protein-free DSB. Proteasomal degradation is often regulated by protein ubiquitination, and here we show that inhibition of ubiquitin-activating enzymes reduces the processing of TOP2A- and TOP2B-DNA complexes. Depletion or inhibition of ubiquitin-activating enzymes indicated that ubiquitination was required for the liberation of etoposide-induced protein-free DSBs and is therefore an important layer of regulation in the repair of TOP2 poison–induced DNA damage. TOP2-DNA complexes stabilized by etoposide were shown to be conjugated to ubiquitin, and this was reduced by inhibition or depletion of ubiquitin-activating enzymes. SIGNIFICANCE STATEMENT There is currently great clinical interest in the ubiquitin-proteasome system and ongoing development of specific inhibitors. The results in this paper show that the therapeutic cytotoxicity of DNA topoisomerase II (TOP2) poisons can be enhanced through combination therapy with ubiquitin-activating enzyme inhibitors or by specific inhibition of the BMI/RING1A ubiquitin ligase, which would lead to increased cellular accumulation or persistence of TOP2-DNA complexes.
Identification of Dopaminergic Neurons That Can Both Establish Associative Memory and Acutely Terminate Its Behavioral Expression

An adaptive transition from exploring the environment in search of vital resources to exploiting these resources once the search was successful is important to all animals. Here we study the neuronal circuitry that allows larval Drosophila melanogaster of either sex to negotiate this exploration-exploitation transition. We do so by combining Pavlovian conditioning with high-resolution behavioral tracking, optogenetic manipulation of individually identified neurons, and EM data-based analyses of synaptic organization. We find that optogenetic activation of the dopaminergic neuron DAN-i1 can both establish memory during training and acutely terminate learned search behavior in a subsequent recall test. Its activation leaves innate behavior unaffected, however. Specifically, DAN-i1 activation can establish associative memories of opposite valence after paired and unpaired training with odor, and its activation during the recall test can terminate the search behavior resulting from either of these memories. Our results further suggest that in its behavioral significance DAN-i1 activation resembles, but does not equal, sugar reward. Dendrogram analyses of all the synaptic connections between DAN-i1 and its two main targets, the Kenyon cells and the mushroom body output neuron MBON-i1, further suggest that the DAN-i1 signals during training and during the recall test could be delivered to the Kenyon cells and to MBON-i1, respectively, within previously unrecognized, locally confined branching structures. This would provide an elegant circuit motif to terminate search on its successful completion. SIGNIFICANCE STATEMENT In the struggle for survival, animals have to explore their environment in search of food. Once food is found, however, it is adaptive to prioritize exploiting it over continuing a search that would now be as pointless as searching for the glasses you are wearing. This exploration-exploitation trade-off is important for animals and humans, as well as for technical search devices. We investigate which of the only 10,000 neurons of a fruit fly larva can tip the balance in this trade-off, and identify a single dopamine neuron called DAN-i1 that can do so. Given the similarities in dopamine neuron function across the animal kingdom, this may reflect a general principle of how search is terminated once it is successful.
Tele-ophthalmology: Need of the hour

Telemedicine and tele-ophthalmology have been in existence since many years, but have recently gained more importance in the present scenario of pandemic COVID-19. The attitude and perception of the doctors and patients has been changing gradually. Telemedicine has many advantages including providing care in inaccesible areas.In the present scenario, tele-ophthalmology gives an oppurtunity to patient for seeking consultation while also protecting against the contagion. There are many barriers faced by the patients and doctors that have restricted use of this technology in the past. However, with a systematic approach to designing the best suited technology, these barriers can be overcome and user friendly platforms can be created. Furthermore, the demand and use of teleconsulation had increased presently in this area of pandemic. Recent survey conducted by the All India Ophthalmological Society also reveals that many ophthalmologists who have not used tele-ophthalmology in the past are more keen to use it presently. In this article, we have reviewed telemedicine and tele-ophthalmology literature on Google and PubMed to get a holistic idea towards teleconsultation, its advantages, increased importance and prefrence during COVID-19 pandemic and various barriers faced so that the known challenges can be understood, which can pave way for better understanding and future incorporation into practice.
Phloem Exudate Protein Profiles during Drought and Recovery Reveal Abiotic Stress Responses in Tomato Vasculature

Drought is the leading cause of agricultural yield loss among all abiotic stresses, and the link between water deficit and phloem protein contents is relatively unexplored. Here we collected phloem exudates from Solanum lycopersicum leaves during periods of drought stress and recovery. Our analysis identified 2558 proteins, the most abundant of which were previously localized to the phloem. Independent of drought, enrichment analysis of the total phloem exudate protein profiles from all samples suggests that the protein content of phloem sap is complex, and includes proteins that function in chaperone systems, branched-chain amino acid synthesis, trehalose metabolism, and RNA silencing. We observed 169 proteins whose abundance changed significantly within the phloem sap, either during drought or recovery. Proteins that became significantly more abundant during drought include members of lipid metabolism, chaperone-mediated protein folding, carboxylic acid metabolism, abscisic acid signaling, cytokinin biosynthesis, and amino acid metabolism. Conversely, proteins involved in lipid signaling, sphingolipid metabolism, cell wall organization, carbohydrate metabolism, and a mitogen-activated protein kinase are decreased during drought. Our experiment has achieved an in-depth profiling of phloem sap protein contents during drought stress and recovery that supports previous findings and provides new evidence that multiple biological processes are involved in drought adaptation.
Comments on: Using corneal graft from keratoconic donor for lamellar and penetrating keratoplasties

recipient buttons for such patients revealed negative reports. However, the histopathology reports were indicative of high inflammatory cell percentage on the basis of which it was assumed that the probable etiology of the adherent leucomas was healed viral keratitis. [5] Given the neurotrophic nature of viral keratitis it corresponds with the fact that they do not respond to either of the treatment modalities. [6] We feel that these cases would respond better if modalities such as neurotisation of the cornea or additional procedures such as the use of auto logus serum are instituted. [7,8]
Seasonal cycles of phytoplankton in relation to the hydrography of Monterey Bay

Annual cycles of relative abundance are described for phytoplankton species collected from Monterey Bay, California, from July 1974 to June 1976, and the population dynamics related to the annual hydrographic cycle. Neritic diatom species dominated the population during the Upwelling and Oceanic periods, with dinoflagellate species becoming numerically more important during the Davidson period. Recurrent species groups identified using Fager's regroup analysis revealed the presence of a large neritic group of overwhelming numerical importance. This group is composed of indigenous species and is present in the bay during most of the year. Conspicuous changes in the phytoplankton population occurred predominantly among species within this group. During the Davidson period, the advection of southern waters into the bay may temporarily displace the endemic species with dinoflagellates becoming numerically more important. A red tide bloom of Gonyaulax polyedra occurred during this period in 1974, which dominated the phytoplankton population for a period of six weeks. The population dynamics of two hydrographically different stations were compared. A station located over the deep waters of the submarine canyon exhibited much lower phytoplankton standing stocks than a station located over the shelf area in the south of the bay, but seasonal changes in relative abundance and species composition were similar. Physical and chemical differences observed between the two stations appear to be the result of the presence of more recently upwelled water in the canyon area, and higher biological utilization in the south of the bay. A close correlation of species diversity with the depth of the mixed layer was observed, with diversity rising with the shoaling of the thermocline. It is suggested that this may reflect the introduction of new species from below the thermocline into the mixed layer as a result of upwelling activity. It is also suggested that this may be an artifact due to sampling problems associated with internal waves. (Document contains 100 pages.)
Metalens-array–based high-dimensional and multiphoton quantum source

Metalens-array–based quantum source Spontaneous down-conversion is an exotic optical process in a nonlinear crystal in which a high-energy photon splits into two lower-energy photons that are quantum mechanically entangled. These entangled pairs are valuable commodities for quantum information processing and quantum communications. Because the experimental setup is usually performed with bulk optical components, there is a need to decrease the size scale for application. Li et al. combined an array of specialized metalenses with a nonlinear crystal and show that the scale of the process can be shrunk substantially. The approach should prove useful for developing miniaturized integrated quantum optical technologies. Science, this issue p. 1487 A metalens array combined with a nonlinear crystal is used to generate high-dimensional entangled photons. The development of two-dimensional metasurfaces has shown great potential in quantum-optical technologies because of the excellent flexibility in light-field manipulation. By integrating a metalens array with a nonlinear crystal, we demonstrate a 100-path spontaneous parametric down-conversion photon-pair source in a 10 × 10 array, which shows promise for high-dimensional entanglement and multiphoton-state generation. We demonstrate two-, three- and four-dimensional two-photon path entanglement with different phases encoded by metalenses with fidelities of 98.4, 96.6, and 95.0%, respectively. Furthermore, four-photon and six-photon generation is observed with high indistinguishability of photons generated from different metalenses. Our metalens-array–based quantum photon source is compact, stable, and controllable, indicating a new platform for integrated quantum devices.
Word-Context Effects in Word Naming and Lexical Decision

Stanovich and West (1983; West and Stanovich, 1982) demonstrated that lexical decisions to target words preceded by incongruous sentence contexts are inhibited more by these contexts than are naming responses to the same target words. They argued that this difference between the two tasks was due to post-lexical processing at the message level that is effective only in the lexical-decision task. The operations of the mechanism thought to underlie this post-lexical effect also predict that, under certain circumstances, the processing of target words congruous with the sentence context should be facilitated more in lexical decision than in naming. The present naming study together with an earlier lexical-decision study tested and confirmed this prediction for word targets following word contexts. The stimulus-onset asynchrony of context word and target word was also varied. This manipulation clearly affected the magnitude of facilitation, indicating that context-induced attentional processing can facilitate lexical access in word-context studies.
Surface modified superparamagnetic iron oxide nanoparticles (SPIONs) for high efficiency folate-receptor targeting with low uptake by macrophages

Superparamagnetic iron oxide nanoparticles (SPIONs) designed to interact with tumor cells have received increasing interest in the past few years, due to their potential for applications such as magnetic resonance imaging (MRI) contrast enhancement, drug delivery, and hyperthermia. However, the stability of these nanoparticles under physiological conditions, and their ability to selectively target tumor cells are challenges which need to be addressed. In this work, SPIONs were first modified with poly(glycidyl methacrylate) (PGMA) via atom transfer radical polymerization (ATRP). The epoxy groups in PGMA were then reacted with ethylenediamine to generate amino groups, which were conjugated with different amounts of folic acid (FA) for cancer cells targeting. The as-synthesized folic acid conjugated SPIONs (SPIONs–PGMA–FA) are hydrophilic and highly stable in an aqueous medium. The targeting efficiency of the folic acid-conjugated nanoparticles was investigated with different cell lines. The uptake of SPIONs–PGMA–FA by KB (human epidermoid carcinoma) cells is about three and five times higher than that of macrophages and 3T3 fibroblasts, respectively. No significant cytotoxicity was observed when the three types of cells were incubated with nanoparticles at a concentration of 0.5 mg mL−1 or less. The nanoparticles also exhibited high MR enhancement effects with r2 and r2/r1 values of 191.4 mM−1 s−1 and 98 respectively in a 3T magnetic field. Hence, these nanoparticles can potentially be used to selectively target cancer cells for imaging as well as hyperthermia.
Effects of Surfactants on the Degradation of Diclofenac by Manganese Oxide

Amine-containing pharmaceuticals are the most often detected pharmaceuticals in wastewater and ambient aquatic environments. They can usually be degraded by manganese oxide (MnO2), which is a common natural oxidant in soils. Surfactants often coexist with pharmaceuticals in wastewater. Some amine-containing pharmaceuticals, such as diclofenac (DIC), are acidic and are thus ionic compounds in neutral conditions. These compounds, therefore, have similar properties to surfactants. Surfactants, thus, may influence the adsorption and degradation processes of DIC by MnO2. The effect of the type of surfactant on the degradation of DIC by MnO2 was investigated in this study with the addition of two common biodegradable surfactants (cetyltrimethyl-ammonium bromide (CTAB) and sodium dodecylsulfate (SDS)). The results indicated that the cationic surfactant (CTAB) significantly increased the degradation rate in neutral and alkaline conditions. On the other hand, the anionic surfactant (SDS) slightly increased the DIC removal rate in an acidic condition but significantly decreased the removal in neutral and alkaline conditions. Coexisting cationic surfactants not only influenced the kinetics but also altered the transformation mechanism of DIC by MnO2. Decarboxylation is the main transformation mechanism of DIC in the presence of CTAB, while both decarboxylation and hydroxylation are the main transformation mechanisms in the absence of CTAB.
Capacidade de combinação entre linhagens de milho visando à produção de milho verde

COMBINING ABILITY OF INBRED LINES OF SWEET CORN In Brazil, there is limited information on the evaluation and development of new genotypes for vegetable corn production and also on genetic studies of traits involved in this production. Thus, this research was conducted to estimate the relative importance of the general combining ability (GCA) and specific combining ability (SCA) in vegetable corn production. Eight inbred lines and 28 hybrids derived from them were evaluated in 2004/2005 season in two environments, in Lavras and Ijaci, State of Minas Gerais. A randomized complete block design with two replications per environment were used, and seven traits of agronomic and commercial interest for vegetable corn production were studied. The quadratic component of specific of combining ability (SCA) was greater than the general combining ability (GCA) for all the traits assessed. Non-additive genetic effects were more important than additive effects for genotypes variation, indicating that heterosis is important for hybrid selection for vegetable corn production. The inbred line L55 showed higher concentration of favorable alleles to the increase of traits PEC, PEE, MASSA, COR e COMP, being more suitable for the formation of new hybrid and the hybrids HS27, HS48 and HS24 accumulated a larger number of traits with SCA positive effect, significant and of high magnitude, indicating that those combinations presented better performance for all the traits, simultaneously, and can be recommended to the market for vegetable corn.
Combining trade data and niche modelling improves predictions of the origin and distribution of non‐native European populations of a globally invasive species

Although propagule pressure and environmental constraints are among the most important factors determining invasion success, studies considering both factors simultaneously are scarce. Moreover, while recent evidence suggests that the environmental requirements of individuals from different geographical ranges may be different, the role of propagule origin in invasions has been largely overlooked. Our aim was to disentangle the relative role of niche requirements, propagule origin and propagule pressure on the distribution of an invasive bird species.
Analysis of Improved power quality of Different types of Buck-Boost Converters with Power Factor Correction

Solid-state Buck-Boost AC-DC converters involve the isolation of high-frequency transformer which develops in Buck-Boost configuration with the improved power quality. Input current with reduced total harmonic distortion (THD), at the supply side in AC mains provides power factor correction. Isolated DC output voltage is fed to high power rating loads. It is represented by the study of improved power quality of different types of buck-boost converters with high-frequency isolation, classification of buck-boost converters with high-frequency isolation, control strategies, components selections and design consideration of buck-boost converter, simulation study, results and discussion, comparison of power density & cost, selection criteria, latest trends, future developments, and potential applications are described. THD analysis has been described in this paper.
ZmCCD10a Encodes a Distinct Type of Carotenoid Cleavage Dioxygenase and Enhances Plant Tolerance to Low Phosphate1

A unified 4-clade phylogenetic tree of CCDs highlights ZmCCD10a, a previously unknown CCD enzyme in terms of cleavage sites, that facilitates plant tolerance to phosphate limitation. Carotenoid cleavage dioxygenases (CCDs) drive carotenoid catabolism to produce various apocarotenoids and immediate derivatives with particular developmental, ecological, and agricultural importance. How CCD genes evolved with species diversification and the resulting functional novelties in cereal crops have remained largely elusive. We constructed a unified four-clade phylogenetic tree of CCDs, revealing a previously unanchored basal clade CCD10. CCD10 underwent highly dynamic duplication or loss events, even in the grass family. Different from cleavage sites of CCD8 and ZAXINONE SYNTHASE (ZAS), maize (Zea mays) ZmCCD10a cleaved differentially structured carotenoids at 5, 6 (5′, 6') and 9, 10 (9', 10') positions, generating C8 (6-methyl-5-hepten-2-one) and C13 (geranylacetone, α-ionone, and β-ionone) apocarotenoids in Escherichia coli. Localized in plastids, ZmCCD10a cleaved neoxanthin, violaxanthin, antheraxathin, lutein, zeaxanthin, and β-carotene in planta, corroborating functional divergence of ZmCCD10a and ZAS. ZmCCD10a expression was dramatically stimulated in maize and teosinte (Z. mays ssp. parviglumis, Z. mays ssp. huehuetenangensis, Zea luxurians, and Zea diploperennis) roots by phosphate (Pi) limitation. ZmCCD10a silencing favored phosphorus retention in the root and reduced phosphorus and biomass accumulation in the shoot under low Pi. Overexpression of ZmCCD10a in Arabidopsis (Arabidopsis thaliana) enhanced plant tolerance to Pi limitation by preferential phosphorus allocation to the shoot. Thus, ZmCCD10a encodes a unique CCD facilitating plant tolerance to Pi limitation. Additionally, ZmCCD10a silencing and overexpression led to coherent alterations in expression of PHOSPHATE STARVATION RESPONSE REGULATOR 1 (PHR1) and Pi transporters, and cis-regulation of ZmCCD10a expression by ZmPHR1;1 and ZmPHR1;2 implies a probable ZmCCD10a-involved regulatory pathway that adjusts Pi allocation.