Two wideband circularly polarized (CP) antenna arrays are proposed, based on sequential rotation (SQR) arranged polarization grid and specially designed wideband full-substrate integrated waveguide ...(SIW) SQR feeding network. First, as the CP array element, an SIW-excited log-periodic dipole array (LPDA) loaded with an inhomogeneous polarization grid is designed. Then, the element with the grid is extended into a <inline-formula> <tex-math notation="LaTeX">2\,\,\times2 </tex-math></inline-formula>-element SQR array, and a wideband planar SIW-feeding cavity is used to provide the full-SIW array feeding. The SQR configuration is simplified by exploring the symmetric property of the LPDA dipole elements for 180° phase shift. Finally, in order to solve the high sidelobe problem existing in the first array design, another full-SIW array configuration with a new 3-D SIW-feeding cavity for the purpose of element spacing reduction is proposed. Another SQR network simplification method is studied here in favor of the 3-D SIW-feeding cavity, in which the out-of-phase power division property of the SIW E-plane junction is explored. With this configuration, a much lower sidelobe result is obtained by the second array. The measured results indicate that both arrays have advantages of wide CP working bandwidth (37%), high efficiencies (~80%), and also wide 3 dB gain bandwidth (39%).
Despite huge efforts have been devoted to investigating ultrathin layers of two-dimensional (2D) transition-metal dichalcogenides (TMDs), their realistic applications in electronics and ...optoelectronics are hindered by limited scalability and uniformity of 2D thin layers. In this work, a two-step synthesis method was adopted to produce wafer-scale molybdenum diselenide (MoSe
2
) nanosheets. Molybdenum oxide (MoO
3
) thin film was initially prepared via atomic layer deposition (ALD) and followed by a selenization process in chemical vapor deposition (CVD) tube furnace. MoSe
2
nanosheets with desired thickness can be obtained by tuning ALD cycles in preparing MoO
3
layers. The synthesized MoSe
2
films exhibited excellent layer controllability, homogeneity and wafer-scale uniformity. Few-layer structure of our MoSe
2
with a polycrystalline crystal structure was verified by means of Raman and transmission electron microscopy (TEM) measurements. Moreover, arrays of MoSe
2
-based photodetectors with different device dimension were fabricated and the photo-responses of the devices were studied. The device exhibited a fast photo-response time of 50 ms, a high on/off ratio of ~ 24 and a good photo-responsivity of 11.7 mA/W, and it is found that the effective illumination area was a critical factor for application. The work opens up an attractive approach to realize the application of wafer-scale 2D materials in integrated optoelectronic-systems.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Previous studies have deciphered the genomic basis of host-symbiont metabolic complementarity in vestimentiferans, bathymodioline mussels, vesicomyid clams and Alviniconcha snails, yet little is ...known about the chemosynthetic symbiosis in Thyasiridae-a family of Bivalvia regarded as an excellent model in chemosymbiosis research due to their wide distribution in both deep-sea and shallow-water habitats. We report the first circular thyasirid symbiont genome, named Candidatus Ruthturnera sp. Tsphm01, with a size of 1.53 Mb, 1521 coding genes and 100% completeness. Compared to its free-living relatives, Ca. Ruthturnera sp. Tsphm01 genome is reduced, lacking components for chemotaxis, citric acid cycle and de novo biosynthesis of small molecules (e.g. amino acids and cofactors), indicating it is likely an obligate intracellular symbiont. Nevertheless, the symbiont retains complete genomic components of sulphur oxidation and assimilation of inorganic carbon, and these systems were highly and actively expressed. Moreover, the symbiont appears well-adapted to anoxic environment, including capable of anaerobic respiration (i.e. reductions of DMSO and nitrate) and possession of a low oxygen-adapted type of cytochrome c oxidase. Analysis of the host transcriptome revealed its metabolic complementarity to the incomplete metabolic pathways of the symbiont and the acquisition of nutrients from the symbiont via phagocytosis and exosome. By providing the first complete genome of reduced size in a thyasirid symbiont, this study enhances our understanding of the diversity of symbiosis that has enabled bivalves to thrive in chemosynthetic habitats. The resources will be widely used in phylogenetic, geographic and evolutionary studies of chemosynthetic bacteria and bivalves.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Metal-organic framework-based composite nanomaterials usually exhibit synergetic properties of their components leading to new functionalities and can be used for a wide range of applications. In ...this study, we designed and synthesized an amine-CQDs@UiO-66 composite fluorescence sensor by integrating amine-functionalized carbon quantum dots (amine-CQDs) and the zirconium-based metal-organic frameworkUiO-66 using a post-synthetic modification approach (PSMA). Herein, UiO-66 was used as an adsorbent to capture and enrich the target molecules selectively and the amine-CQDs were employed as a functional monomer to selectively and sensitively sense the bonding interactions between UiO-66 and the target molecules, andfurther transduce these chemical events into detectable fluorescence signals. The resulting amine-CQDs@UiO-66 sensor exhibited excellent fluorescence selectivity and sensitivity toward 4-nitrophenol (4-NP) because of the immobilized highly fluorescent amine-CQDs. The fluorescence sensitivity was increased because of the enrichment of 4-NP that originated from the well-defined microporous MOF. Moreover, 4-NP could be detected in a wide concentration range of 0.01–20.0 μM with a detectionlimit as low as 3.5 nM. To the best of our knowledge, this work presents the first combination of the fluorescence functional monomer amine-CQDs with the favorable properties of MOFs by PSMA for selective fluorescence sensing.
We fabricated amine-CQDs@UiO-66 composites via a post-synthetic modification approach, incorporating amine-functionalized carbon quantum dots functional monomers that could respond to the analyte 4-nitrophenol (4-NP). We found it to be highly selective and sensitive for 4-NP, detecting this species even in mixtures of metal ions and other phenols. Display omitted
•Amine-CQDs@UiO-66 composites were prepared via post-synthetic approach.•Amine-CQDs@UiO-66 composites were found to be excellent FL probes for 4-NP detection.•Amine-CQDs@UiO-66 composites have high selective sensing performance for 4-NP.
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GEOZS, IJS, IMTLJ, KILJ, KISLJ, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, UILJ, UL, UM, UPCLJ, UPUK, ZAGLJ, ZRSKP
Microwave phased array antennas (PAAs) are very attractive to defense applications and high-speed wireless communications for their abilities of fast beam scanning and complex beam pattern control. ...However, traditional PAAs based on phase shifters suffer from the beam-squint problem and have limited bandwidths. True-time-delay (TTD) beamforming based on low-loss photonic delay lines can solve this problem. But it is still quite challenging to build large-scale photonic TTD beamformers due to their high hardware complexity. In this paper, we demonstrate a photonic TTD beamforming network based on a miniature microresonator frequency comb (microcomb) source and dispersive time delay. A method incorporating optical phase modulation and programmable spectral shaping is proposed for positive and negative apodization weighting to achieve arbitrary microwave beam pattern control. The experimentally demonstrated TTD beamforming network can support a PAA with 21 elements. The microwave frequency range is 8-20 GHz; and the beam scanning range is ±60.2°. Detailed measurements of the microwave amplitudes and phases are performed. The beamforming performances of Gaussian, rectangular beams, and beam notch steering are evaluated through simulations by assuming a uniform radiating antenna array. The scheme can potentially support larger PAAs with hundreds of elements by increasing the number of comb lines with broadband microcomb generation.
Radiation therapy for cancer can lead to off-target toxicity and can be ineffective against hypoxic solid tumours and distant metastases. Here, we show that intratumoral injection, in mouse and ...rabbit xenografts and in patient-derived mouse xenografts, of a sodium alginate formulation containing catalase (Cat) labelled with the therapeutic
I radioisotope enables long-term relief of tumour hypoxia and complete tumour elimination at low radioactivity doses. On injection, the soluble polysaccharide rapidly transforms into a hydrogel in the presence of endogenous Ca
, fixing
I-Cat within the tumours. We also show that local radiotherapy with a formulation that includes the immunostimulatory CpG oligonucleotide combined with systemic checkpoint-blockade therapy using an anti-CTLA-4 antibody leads to metastasis inhibition and protection against tumour rechallenge. The local therapy, which uses only biocompatible components, might enable new strategies for local tumour treatments that can be combined with systemic therapeutic responses, for the inhibition of tumour metastasis and the prevention of tumour recurrence in patients with advanced-stage cancer.
Noroviruses are one of the major causes of acute human nonbacterial gastroenteritis, and genotype II.4 (GII.4) has accounted for the majority of adult outbreaks. In addition, novel epidemic strain ...emerges every 2 to 3 years and spreads globally in months. There are little data reporting the evolutionary dynamics of GII.4 variants along a specific period in China.
All norovirus GII.4 sequences in China were downloaded from GenBank Database. Phylogenetic tree was constructed by MEGA and Bayesian evolutionary inference techniques were applied by BEAST software to study the genetic relationships, evolution rate, evolutionary time scale and the demographic history of GII.4 variants. Homology models were predicted by SWISS-MODEL to analyze the spatial structure changes.
During the 12-year period, 624 GII.4 sequences were subtyped into six GII.4 variants (clusters). A rate of 4.74×10-3, 6.99×10-3 and 7.68×10-3 nucleotide substitutions/site/year for the strict, uncorrelated log-normal and uncorrelated exponential derivation clocks were estimated, respectively. Three amino acid mutations (G255S, S393G and H414P) in both Den Haag_2006b sub-clusters and six mutations (I244T, N309S, A377T, T244I, T377A and S393G) in three Sydney_2012 sub-clusters were observed.
The temporal distribution pattern of noroviruses GII.4 lineages in China was similar to the worldwide observation. The evolutionary rate of GII.4 was consistent with the global studies. Amino acid changes in the vicinity of norovirus epitope may have profound influences on carbohydrate binding affinity between different sub-clusters of norovirus variants. Hence understanding the evolutionary dynamics of norovirus is of great value for developing effective prevention and control strategies.
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DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Cyclodextrin (CD)‐based polyrotaxanes (PR) are widely used to construct high‐mechanical‐performance materials because of the high degree of conformational freedom. However, strong hydrogen bonds ...between CDs greatly limit the application of CD‐PR in the preparation of ductile neutral hydrogels. In this work, spiropyrane (SP) into α‐CD‐based PR is introduced to “visualize” the segment motion of the network in neutral water. The aggregation‐induced cohesion and critical factors for the force transmission are disclosed. This system offers a new approach for the fundamental research for the complicated topologically cross‐linked structures, which is important for the design of CD‐PR‐based biocompatible soft materials.
A chromic mechanophore is incorporated into cyclodextrin‐based polyrotaxane (CD‐PR) gels to “visualize” the microstructure evolution of CD‐PR in water. The solvent‐induced cohesion and the mechanism of force conduction are revealed. This work lays a fundamental basis for the design of highly ductile CD‐PR hydrogels, which can broaden the application of mechanically interlocked polymers in biocompatible soft materials.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
Studies have shown that neural responses following concentric (CON) and eccentric (ECC) muscle contractions are different, which suggests differences in motor control associated with CON and ECC ...contractions. This study aims to determine brain activation of the left primary motor cortex (M1) and left and right dorsolateral prefrontal cortices (DLPFCs) during ECC and CON of the right bicep brachii (BB) muscle at low‐ and high‐contraction intensities. Eighteen young adults (13M/5F, 21–35 years) were recruited to participate in one familiarization and two testing sessions in a randomized crossover design. During each testing session, participants performed either ECC or CON contractions of the BB (3 sets × 8 reps) at low‐ (25% of maximum ECC/CON, 45°/s) and high‐intensity (75% of maximum ECC/CON, 45°/s) on an isokinetic dynamometer. Eleven‐channel functional near‐infrared spectroscopy was used to measure changes in oxyhemoglobin (O2Hb) from the left M1, and left and right DLPFC during ECC and CON contractions. Maximum torque for ECC was higher than CON (43.3 ± 14.1 vs. 46.2 ± 15.7 N m, p = 0.025); however, no differences in O2Hb were observed between contraction types at low or high intensities in measured brain regions. High‐intensity ECC and CON contractions resulted in greater increases in O2Hb of M1 and bilateral DLPFC compared to low‐intensity ECC and CON contractions (p = 0.014). Our findings suggest no differences in O2Hb responses between contraction types at high and low intensities. High‐contraction intensities resulted in greater brain activation of the M1 and bilateral DLPFC, which may have implications for neurorehabilitation to increase central adaptations from exercise.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
A novel type of bio‐nanoreactor with catalase loaded inside TaOx hollow nanoshells is fabricated via a mild one‐step method. Such bio‐nanoreactors could efficiently improve the tumor oxygenation by ...supplying oxygen via decomposition of endogenic H2O2 in a tumor microenvironment, and thus synergistically enhance the efficacy of cancer radiotherapy by both depositing radiation energy within the tumor and overcoming hypoxia‐induced radiotherapy resistance.
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BFBNIB, FZAB, GIS, IJS, KILJ, NLZOH, NUK, OILJ, SBCE, SBMB, UL, UM, UPUK
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