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Microstrip antenna loaded with focusing metasurface for high-gain dual-polarization and bidirectional radiation
In this paper, we propose a microstrip antenna that incorporates a dual-polarization and bidirectional focusing metasurface (MS) for achieving high-gain transmission in circular polarization (CP) and reflection in linear polarization (LP) radiation, respectively. Initially, we design a MS that enables independent manipulation of the transmitted CP wave at a lower frequency of 8.2 GHz and the reflected LP wave at a higher frequency of 16.2 GHz, respectively. The unit-cell of the MS comprises a combination of an outer bilayered split-ring resonator, along with inner arc-shaped and disk resonators, all separated by a dielectric substrate. Subsequently, a coaxial-fed laminated microstrip antenna is designed that is capable of realizing CP radiation with a gain of approximately 4.9 dBic at 8.2 GHz and LP radiation at 16.2 GHz with a gain of 4.8 dBi, respectively. To improve the radiation performance, we construct a coaxial-fed laminated microstrip antenna integrated with a dual-polarization and bidirectional focusing MS. This configuration enables the antenna to achieve high-gain CP radiation in transmission at 8.2 GHz with a peak gain of 13.1 dBic and high-gain LP radiation in reflection with a peak gain of 14.6 dBi at 16.2 GHz, respectively. The relative bandwidth of the MS antenna is 6.79% (at 8.2 GHz) of the transmitted CP wave and 13.54% (at 16.2 GHz) of the reflective LP wave, respectively. To evaluate the practicality of our proposed design, we fabricated and measured a coaxial-fed laminated microstrip antenna, both with and without the MS. The results obtained from these measurements closely align with our simulations, thereby validating the effectiveness of our proposed dual-polarization and bidirectional MS antenna. This antenna provides a practical solution for achieving dual-polarization radiation and facilitating high-speed information transmission in communication systems.
Recombinant venom proteins in insect seminal fluid reduce female lifespan
A combined 2<i>ω</i>/3<i>ω</i> method for the measurement of the in-plane thermal conductivity of thin films in multilayer stacks: Application to a silicon-on-insulator wafer
This study focuses on establishing and validating a method to accurately measure the in-plane thermal conductivity of very conductive thin films, such as single-crystal metals or semiconductors, 2D and nanostructured materials. By integrating both 2ω and 3ω measurements, the method is rendered insensitive to the superficial thermal boundary resistance of the insulating overlayer, enabling precise estimation of the in-plane thermal properties of conductive films grown on top of substrates or multilayer stacks. The proposed technique is applied to analyze the thermal conductivity of a silicon-on-insulator stack with a top layer consisting of a 340 nm thick film of monocrystalline silicon. Measurements are conducted within a temperature range spanning from 250 to 325 K. The results confirm the method’s capability to correctly assess the thermal conductivity decrease of the silicon film compared to bulk value, demonstrating its reliability for the thermal characterization of conductive thin films.
QRFP43 modulates the activity of the hypothalamic-pituitary-thyroid axis in female sheep
AbstractSince the early discovery of QRFP43, intensive research has been primarily focused on its role in the modulation of food intake. As is widely recognised, the regulation of the body’s energy status is a highly complex process involving numerous systems, hormones and neurotransmitters. Among the most important regulators of energy status, alongside the satiety and hunger centre located in the hypothalamus, is the HPT axis, which directly and indirectly affects the regulation of metabolism in all cells of the body. Therefore, it seems highly important to conduct studies aimed at elucidating how QRFP43 may impact the secretory activity of the HPT axis. The objective of this work was to investigate the role of QRFP43 in modulating HPT axis activity in sheep. The study examined mRNA and peptide expression of TRH and TSH in the hypothalamus and pituitary, as well as plasma concentrations of TSH, free T4 (FT4) and free T3 (FT3). Moreover, the relationship between QRFP34 and mRNA expression of the Dio1, Dio2, and Dio3 genes was explored in selected tissues of the HPT axis. The animals (n = 48) were randomly divided into three experimental groups: a control group receiving an ICV infusion of Ringer-Locke solution, and two experimental groups receiving ICV infusions of QRFP43 at doses of 10 and 50 µg per day. Four 50-minute ICV infusions were administered to all sheep at 30 min intervals each of three consecutive days. Hypothalamic, pituitary and thyroid glands were collected and preserved for further immunohistochemical and molecular biological analyses. Additionally, blood samples were collected during the experiment for subsequent RIA determinations. In summary, the results of the experiment have indicated that QRFP43 modulates the secretory activity of the HPT axis at all organisational levels. Moreover, QRFP43 can alter the mRNA expression profiles of DIO1, DIO2 and DIO3 in HPT tissues, leading to discrete changes in the metabolism of the cells studied and their response to signals transmitted by T4 and T3.
UnidecNMR: automatic peak detection for NMR spectra in 1-4 dimensions
Abstract To extract information from NMR experiments, users need to identify the number of resonances in the spectrum, together with characteristic features such as chemical shifts and intensities. In many applications, particularly those involving biomolecules, this procedure is typically a manual and laborious process. While many algorithms are available to tackle this problem, their performance tends to be inferior to that of an experienced user. Here, we introduce UnidecNMR, which identifies resonances in NMR spectra using deconvolution. We demonstrate its favourable performance on 1 and 2D simulated spectra, strongly overlapped 1D spectra of oligosaccharides and 2D HSQC, 3D HNCO, 3D HNCA and 3/4D methyl-methyl NOE experimental spectra from a range of proteins. UnidecNMR outperforms a number of freely available algorithms and provides results comparable to those generated manually. Introducing additional restraints, such as a 2D peak list when analysing 3 and 4D data and incorporating reflection symmetry in NOE analysis further improves the results. UnidecNMR outputs a back-calculated spectrum and a peak list, both of which can be easily examined using the supplied GUI. The software allows interactive processing using nmrPipe, allowing users to go directly from raw data to processed spectra with picked peak lists.
Enhancing the superconducting properties of bulk (Sm,Eu,Gd)Ba2Cu3O7−δ: Impact of BaO2 and Ag2O addition via infiltration growth process in air
The air fabrication of bulk LREBa2Cu3O7−δ [where LRE can be Nd, Sm, Eu, Gd, or combinations such as (Y,Gd), (Y,Er), (Sm,Eu,Gd), (Nd,Eu,Gd), and (Nd,Sm,Gd)] holds the potential to revolutionize the cost-effective production of high-temperature superconductors. This method enables batch processing on an industrial scale, opening up a range of applications across various fields with enhanced superconducting performance. In this study, we fabricated large single-domain (Sm,Eu,Gd)Ba2Cu3O7−δ using the top-seeded infiltration growth process in air. To suppress the RE/Ba substitutions, BaO2 was added in the secondary (Sm,Eu,Gd)2BaCuO5 (SEG-211) phase with various BaO2 weight percentages. The optimized sample achieved an onset critical temperature Tc(onset) of 94.57 K and a transition width of ΔTc &lt; 1 K, representing a 71% improvement in ΔTc over the reference sample. Furthermore, the self-field critical current density Jc of the BaO2-optimized sample was 33.55 kA/cm2 at 77 K and 62.26 kA/cm2 at 65 K, H//c-axis. The addition of Ag2O to the BaO2-optimized sample yielded an onset critical temperature of Tc(onset) &gt; 93 K and a transition width of ΔTc &lt; 1.5 K. Significant improvement in high-field critical current density was observed in the Ag2O-added sample, with a Jc value of 18.14 kA/cm2 at 77 K and 1 T, and 50.54 kA/cm2 at 65 K and 3 T, H//c-axis. These results indicate that ternary (Sm,Eu,Gd)Ba2Cu3O7−δ can be produced in air using the IG process with optimal BaO2 and Ag2O, which is crucial for batch production in air.
Antimicrobial susceptibility profiles of Mycoplasma hyosynoviae strains isolated from five European countries between 2018 and 2023
AbstractMycoplasma (M.) hyosynoviae is a facultative pathogen, causing arthritis in finisher pigs world-wide. In the absence of a commercial vaccine improvement of housing conditions and antibiotic therapy are the only options to alleviate the clinical signs. This study aimed to determine antibiotic susceptibility profiles of 106 M. hyosynoviae isolates against ten antibiotics licensed for veterinary use in cases of arthritis. The isolates were collected between 2018 and 2023 from five European countries: Austria (n = 20), Belgium (n = 20), Germany (n = 25), Hungary (n = 21) and Italy (n = 20). The minimal inhibitory concentrations (MIC) were determined by broth micro-dilution assay. The tested isolates were highly susceptible to tiamulin (MIC90 ≤ 0.039 µg/ml), tylvalosin (MIC90 ≤ 0.039 µg/ml) and lincomycin (MIC90 ≤ 0.25 µg/ml). Low concentrations of tylosin (MIC90 0.5 µg/ml) and tilmicosin (MIC90 1 µg/ml) inhibited the growth of the isolates. While moderate minimal inhibitory concentrations were detected for doxycycline (MIC90 0.312 µg/ml), oxytetracycline (MIC90 2 µg/ml), enrofloxacin (MIC90 0.625 µg/ml) and florfenicol (MIC90 2 µg/ml), only high concentrations of tulathromycin (MIC90 64 µg/ml) inhibited the growth of the isolates. Statistical analysis revealed significant differences between countries in case of enrofloxacin, where the Hungarian isolates showed the lowest MIC values, and the German isolates the highest MIC values among the tested countries. Our results show that European M. hyosynoviae isolates are generally susceptible to the tested antibiotics with the exception of tulathromycin. The country specific differences indicate the importance of regular susceptibility testing of isolates on a Pan-European level.
Multivalent S2 subunit vaccines provide broad protection against Clade 1 sarbecoviruses in female mice
Photoluminescence, energy transfer, and quantum yield studies of CaF2:Tb3+–Ce3+: Latent fingerprints and anticounterfeit applications
Ce3+ co-doped CaF2: Tb3+ nanoparticles were synthesized by a hydrothermal method using l-glutamic acid as a capping agent. When the concentration of a Ce3+ ion increases, peak broadening in the X-ray Diffraction (XRD) pattern takes place, indicating strain developed in a lattice. The XRD pattern shows no extra peak for Ce3+ ions up to 13 at. % co-doped in CaF2:5 at. % Tb3+. However, Transmission Electron Microscopy (TEM) analysis shows an extra phase of an LnF3 hexagonal phase at even lower concentrations (&lt;13 at. %). This is due to the charge imbalance between Ce3+ and Ca2+. Two main emission peaks at 488 and 541 nm of Tb3+ are observed through direct (377 nm) and indirect excitations (302 nm). Enhancement in the luminescence intensity of Tb3+ emission is observed when Ce3+ is incorporated in CaF2: Tb3+. This corresponds to the efficient energy transfer from Ce3+ to Tb3+. Under the excitation of 302 nm, the energy transfer efficiency reaches up to 86%. The decay lifetime of Ce3+ for Tb3+ co-doping with CaF2:5 at. % Ce3+ decreases from 24 to 11 ns with the increase of Tb3+ concentration (0–5 at. %), indicating energy transfer from Ce3+ to Tb3+. The main interaction(s) of energy transfer is observed through a dipole–dipole interaction. The maximum quantum yield value for 2 at. % Tb3+ co-doped CaF2:5 at. % Ce3+ of ∼49% is observed. Energy transfer is confirmed by calculated radiative and non-radiative decay rate constants.
Formulation development and evaluation, in silico PBPK modeling and in vivo pharmacodynamic studies of clozapine matrix type transdermal patches
Activity of the mammalian DNA transposon piggyBat from Myotis lucifugus is restricted by its own transposon ends
AbstractMembers of the piggyBac superfamily of DNA transposons are widely distributed in host genomes ranging from insects to mammals. The human genome has retained five piggyBac-derived genes as domesticated elements although they are no longer mobile. Here, we have investigated the transposition properties of piggyBat from Myotis lucifugus, the only known active mammalian DNA transposon, and show that its low activity in human cells is due to subterminal inhibitory DNA sequences. Activity can be dramatically improved by their removal, suggesting the existence of a mechanism for the suppression of transposon activity. The cryo-electron microscopy structure of the piggyBat transposase pre-synaptic complex showed an unexpected mode of DNA binding and recognition using C-terminal domains that are topologically different from those of the piggyBac transposase. Here we show that structure-based rational re-engineering of the transposase through the removal of putative phosphorylation sites and a changed domain organization - in combination with truncated transposon ends - results in a transposition system that is at least 100-fold more active than wild-type piggyBat.
Non-ionizing cross section of electron scattering on atoms in matter accounting for dynamical screening effect
We present a model of non-ionizing scattering of electrons on atomic ensemble in matter, applicable in a wide electron energy range from ∼eV up to relativistic ones. The approach based on the dynamic-structure factor formalism considers collective response of the atomic and electronic systems of a target. It accounts for dynamical screening of atomic nuclei in matter by valence (collective) and core–shell electrons during the scattering events, dependent on the incident electron velocity. The proposed formalism for the cross section enables us to describe in a unified manner the electron scattering on the ensemble of isolated atomic nuclei at high incident electron energies, reducing to the scattering on phonons with a decrease in the energy. Our model can be used, e.g., in transport Monte Carlo codes to describe the energy exchange between excited electrons and atomic ensemble in matter. An example of swift heavy ion track formation in quartz simulated with the proposed cross section shows reasonable agreement with the experiment validating the model.
Regulation of fibronectin and collagens type I, III and VI by TNF-α, TGF-β, IL-13, and tofacitinib
DNA targeting by compact Cas9d and its resurrected ancestor
AbstractType II CRISPR endonucleases are widely used programmable genome editing tools. Recently, CRISPR-Cas systems with highly compact nucleases have been discovered, including Cas9d (a type II-D nuclease). Here, we report the cryo-EM structures of a Cas9d nuclease (747 amino acids in length) in multiple functional states, revealing a stepwise process of DNA targeting involving a conformational switch in a REC2 domain insertion. Our structures provide insights into the intricately folded guide RNA which acts as a structural scaffold to anchor small, flexible protein domains for DNA recognition. The sgRNA can be truncated by up to ~25% yet still retain activity in vivo. Using ancestral sequence reconstruction, we generated compact nucleases capable of efficient genome editing in mammalian cells. Collectively, our results provide mechanistic insights into the evolution and DNA targeting of diverse type II CRISPR-Cas systems, providing a blueprint for future re-engineering of minimal RNA-guided DNA endonucleases.
Laser-wavelength dependence of ultrafast demagnetization in ferromagnetic metals
Laser-induced ultrafast demagnetization (UD) in ferromagnetic metals opens a new frontier at the intersection between laser technology and materials sciences. However, a complete understanding is still missing even in simple 3d metals. Prior studies have often concentrated on the effect of laser fluence on UD, but whether and how the wavelength affects UD remain under explored. Here, we propose a new perspective that is based on laser wavelength. We show, via the example of fcc Ni, that without intraband transitions, wavelength has a significant impact on UD but the spin moment reduction is small. With the intraband transition, UD weakly depends on wavelength, but with a large spin reduction. The time-resolved electron and spin density of states reveals that electrons around the Fermi energy are largely responsible for strong demagnetization, which almost wipes out the imprint of the photon energy on demagnetization, explaining the experimental observation. A significant spin reduction is found when a large portion of the unoccupied minority states slightly above the Fermi level becomes occupied.
Individual differences in temporal order judgment
Acceptor engineering of quinone-based cycloparaphenylenes via post-synthesis for achieving white-light emission in single-molecule
Twinning and strain induced modifications in insulator-metal transition and large magnetoresistance in La0.67Ca0.33MnO3 films
The physical characteristics of epitaxially sputtered La0.67Ca0.33MnO3 (LCMO) films are modified by twinning when deposited on different single crystal substrates at varying thicknesses. Comprehensive high-resolution x-ray diffraction measurements reveal the formation of two types of tilted domains, whose influence becomes prominent in rocking curve scans with increasing thickness. The occurrence of twinning is attributed to the shear strain relaxation process that accommodates the lattice symmetry mismatch between the film and the substrate. In the electrical transport properties of thicker films, the effect of twinning manifests as a broadening of the insulator–metal transition in resistance–temperature (R–T) plots, in which an extra hump emerges. This broadening effect is also noticeable in magnetoresistance curves, leading to a large magnetoresistance spread over a broad temperature range. While the additional hump in R–T plots vanishes under stronger magnetic fields, the persistent broadening of the transition and magnetoresistance suggests that twinning continues to influence the film properties even at higher field strengths. Thick LCMO films exhibit similar broadening in the transition from the paramagnetic to ferromagnetic phase with an additional transition during magnetic (M–T) measurements. In contrast, LCMO films of lesser thickness display sharp electrical and magnetic transitions without significant evidence of any supplementary transition. These results suggest that the twinning effect in films, caused by substrate-induced strain relaxation, can profoundly alter the transport properties of these functional films and substantially widen the temperature range where maximum magnetoresistance is observed.