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A dual-band dual-linearly polarized waveguide slot array antenna is proposed in this paper. Two orthogonal slots share a short-circuit wall on broad side. The horizontal and vertical slots, which actualize dual-frequency bands and dual-linear polarization, generate vertically polarized electric fields in 9.39–9.78 GHz and horizontally polarized electric fields in 11.62–12.3 GHz, respectively. The equivalent permittivity of the waveguide is changed by two grooves at the bottom of the waveguide, which improves phase velocity. Two grooves can also reduce the distance between the elements while suppressing the side lobes. Compared to filling the medium in the waveguide, two grooves have less losses. Moreover, the antenna is simple with one input port. The array antenna also overcomes the problems of beam scanning compared with the traditional waveguide slot array antenna. A 1 × 8 antenna array is fabricated and measured to verify the design. The horizontal polarization is formed in 9.39–9.78 GHz, the vertical polarization is generated in 11.62–12.3 GHz, and the antenna gain can reach 15 dBi.
The 4.2 ka event is widely presumed to be a globally widespread aridity event and has been linked to several episodes of societal changes across the globe. Whether this climate event impacted the cultural development in south-central China remains uncertain due to a lack of regional paleorainfall records. We present here stalagmite stable carbon isotope and trace element–based reconstruction of hydroclimatic conditions from south-central China. Our data reveal a sub–millennial scale (~5.6 to 4.3 ka) drying trend in the region followed by a gradual transition to wetter conditions during the 4.2 ka event (4.3–3.9 ka). Together with the existing archaeological evidence, our data suggest that the drier climate before 4.3 ka may have promoted the Shijiahe culture, while the pluvial conditions during the 4.2 ka event may have adversely affected its settlements in low-lying areas. While military conflicts with the Wangwan III culture may have accelerated the collapse of Shijiahe culture, we suggest that the joint effects of climate and the region's topography also played important causal roles in its demise.
A novel wide 3-dB axial ratio (AR) circularly polarized 2 × 2 array antenna is proposed in this paper. The spindle-shaped coupling cavity with tilted waveguide is capable of generating circular polarization waves from incident linear waves, which improves the AR bandwidth (ARBW) of the antenna. With this structure, a similar amplitude of the two orthogonal transmitted wave components and a stable phase difference of nearly 90° can be generated. The circularly polarized antenna proposed herein has been fabricated. According to the measurement results, the operating bandwidth from 5.32 to 6.13 GHz is <−10 dB. In addition, the measured ARBW, which is below 3 dB, can cover the range of 5.41–6.02 GHz. The maximum gain of the antenna can attain 15.65 dBi, and the efficiency is better than 80%.
Novel NiMoO4-integrated electrode materials were successfully prepared by solvothermal method using Na2MoO4·2H2O and NiSO4·6H2O as main raw materials, water, and ethanol as solvents. The morphology, phase, and structure of the as-prepared materials were characterized by SEM, XRD, Raman, and FT-IR. The electrochemical properties of the materials in supercapacitors were investigated by cyclic voltammetry, constant current charge–discharge, and electrochemical impedance spectroscopy techniques. The effects of volume ratio of water to ethanol (W/E) in solvent on the properties of the product were studied. The results show that the pure phase monoclinic crystal NiMoO4 product can be obtained when the W/E is 2:1. The diameter and length are 0.1–0.3 µm and approximately 3 µm, respectively. As an active material for supercapacitor, the NiMoO4 nanorods material delivered a discharge specific capacitance of 672, 498, and 396 F/g at a current density of 4, 7, and 10 A/g, respectively. The discharge specific capacitance slightly decreased from 815 to 588 F/g with a retention of 72% after 1000 cycles at a current density of 1 A/g. With these superior capacitance properties, the novel NiMoO4 integrated electrode materials could be considered as promising material for supercapacitors.
We investigated the effect of human induced pluripotent stem cell (hiPS) medium on porcine somatic cell nuclear transfer and bovine in vitro fertilized early blastocysts, in comparison with North Carolina State University (NCSU)-37 medium and in vitro culture (IVC)-II medium. After 2 days of culture, the diameter of the portion of the blastocyst that was extruded from the zona pellucid dramatically differed between porcine blastocysts cultured in hiPS medium and those cultured in NCSU-37 medium (221.47 ± 38.94 μm versus 481.87 ± 40.61 μm, P < 0.01). Moreover, the diameter of the portion of the blastocyst significantly differed between bovine blastocysts cultured in hiPS medium and those cultured in IVC-II medium (150.30 ± 29.49 μm versus 195.58 ± 41.59 μm, P < 0.01). Furthermore, the total number of cells per porcine and bovine blastocyst was more than two-fold higher in blastocysts cultured in hiPS medium than in those cultured in NCSU-37 medium (44.33 ± 5.28 and 143.33 ± 16.05, P < 0.01) or IVC-II medium (172.12 ± 45.08 and 604.83 ± 242.64, P < 0.01), respectively. These results indicate that hiPS medium markedly improves the quality of porcine and bovine blastocysts.
Single-nucleotide polymorphisms (SNPs) of exon 8 of the GHR gene were detected in Chinese Holstein cows by polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). The results showed that exon 8 of the GHR gene digested by TasI could be divided into two kinds of alleles and three kinds of genotypes. The frequencies of allele A and T were 0.6339 and 0.3661, respectively. The frequencies of genotypes AA, AT and TT were 0.459, 0.350 and 0.191, respectively. Sequencing showed one single nucleotide mutation T→A at 4962 bp of the gene in genotype TT when compared with genotype AA, and this mutation resulted in an amino acid change of phenylalanine (TTT)→tyrosine (TAT). The result of χ2 testing indicated that the genotypic frequency of the GHR gene digested by TasI did not fit with Hardy–Weinberg equilibrium in this population (P<0.05). The least-square mean of the fat percentage of this population was higher for genotype TT than for genotype AA (P<0.05).
The spatio-temporal expressed profiles of two kinds of chemical communication-related protein genes, the odorant-binding protein of Ac-ASP2 and chemosensory protein of Ac-ASP3, were identified by real-time polymerase chain reaction (PCR). Results obtained using the 2−ΔΔCt method showed that Ac-ASP2 was a gene coding antenna-specific protein that did not express in larvae and pupae, but had discontinuous high abundance periods at 1, 9, 15, 27 and 30 days. The expressing abundance at such periods was at least ten times higher than that at other periods. From the distribution of Ac-ASP3 mRNA observed in different tissues, the transcript levels seemed to be higher in the wings, abdomen and thorax (of order ~106), and lower in the legs, antennae and head (of order ~105). From highest to lowest, the original copy number was found in the various body parts in the following order: wings, abdomen, thorax, legs, antenna, and head. The results suggest that Ac-ASP3 has an intimate relation with the chemosensory behaviour of wings and abdomen in Apis cerana cerana.
The arterial supply of the digits of the forelimb of the Bactrian camel is described. The arteries supplying
the digits were the palmar metacarpal and common palmar digital arteries III. The palmar metacarpal artery
III was the continuation of the deep medial proximal metacarpal branch which was derived from the medial
branch of the radial artery. It gave rise to a nutrient branch, medial branch, lateral branch and distal
perforating palmar branch at the proximal end of the distal sixth of the cannon bone (fused third and
fourth metacarpal bones). The common palmar digital artery III was the continuation of the median artery,
which divided into medial and lateral branches. The medial branch of common palmar digital artery III
which occasionally arose from the axial palmar proper digital artery III, after giving rise to the axial
proximal proximal phalangeal branch, divided into the axial and abaxial palmar proper digital arteries III.
The axial palmar proper digital artery III gave off the dorsoaxial distal proximal phalangeal, dorsoaxial
proximal middle phalangeal, dorsoaxial distal middle phalangeal, palmoaxial middle phalangeal, palmoaxial
distal phalangeal, dorsoaxial distal phalangeal branches, coronal artery and some digital tori branches. The
abaxial palmar proper digital artery III gave rise to the abaxial proximal proximal phalangeal, dorsoabaxial
distal proximal phalangeal, dorsoabaxial middle phalangeal, palmoabaxial middle phalangeal, palmoabaxial
distal phalangeal, dorsoabaxial distal phalangeal branches, coronal artery and some digital tori branches.
The lateral branch of the common palmar digital artery III in its origin, course, branching pattern and
supply in the fourth digit was similar to the medial branch of common palmar digital artery III in the third
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