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In this article, novel packaged wideband highly selective filtering power dividers (FPDs) with arbitrary phase shifts and power dividing ratios using multilayer stacked stripline are presented, for the first time. In the proposal, the arbitrary phase shift $\Delta \Phi $ and power dividing ratio $k^{2}$ are mainly attained by developing a novel topology consisting of a looped double-coupled line (LDCL)-based power dividing section, a pair of shorted stubs and a delay line. And, it requires no additional output transformers to terminals under arbitrary power dividing ratios. In addition, a co-shared structure composed of a transmission line and an open-circuit stepped impendence stub is inserted in front of the proposed LDCL, which can enhance the flexibility of overall impedance requirement and bring more transmission poles (TPs) and a pair of transmission zeros (TZs), realizing a wide and high-selective filtering bandwidth and enhanced isolation. A comprehensive analysis is carried out to guide the proposed FPDs design in detail. For verification, two design prototypes are implemented in self-packaged forms using the multilayer stacked stripline printed circuit board (PCB) technology. Prototype I is a FPD with 84% 3-dB FBW, phase shift $\Delta \Phi $ = 45°, and power dividing ratio $k^{2}$ = 1, while prototype II is an FPD with 72% 3-dB FBW, phase shift $\Delta \Phi $ = 90°, and power dividing ratio $k^{2}$ = 6. Simulated and measured results are provided with satisfying agreement among them.

In Chinese paintings, the marriage of rice paper and ink is the soul of this art. Ink possesses a highly distinctive “color” expressiveness. By employing ink, various shades of black and diverse color effects can be portrayed, making the image more rich, vibrant, and three-dimensional on a rice paper. However, when used in traditional ink wash painting, the flow and penetration of conventional ink is difficult to control, and its carbon black particles make it a challenge to achieve multiple transparent gradients. Considering the water solubility and two-dimensional nanostructure of graphene oxide (GO), the authors of this paper has developed and proposed the use of water-based GO ink for Chinese ink wash painting, aiming to endow it with new aesthetic forms and unique expressive potentials.

This article proposes a novel microwave displacement sensor based on a filtering phase shifter (FPS), which can provide displacement sensing and intrinsic filtering functions simultaneously. The FPS comprises a third-order Chebyshev bandpass filter (BPF) network and a pair of transmission lines. With the derived closed-form formula of magnitude and phase response of the proposed FPS structure, variable insertion phase and constant filtering response characteristics are applied to design the linear displacement sensors for the first time. The displacement sensor mainly consists of double layers, where a pair of fixed transmission lines connect two ports in the first layer as a stator and an FPS structure in the second layer as a movable contact slider. The insertion phase drifts linearly along the displacement, while the bandpass filtering response remains unchanged. A proof-of-concept microstrip sensor prototype operating at 2.98 GHz is implemented and tested to validate the proposed method experimentally. The measured results are in good agreement with the simulated ones, which shows that the proposed sensors can achieve an average phase sensitivity of about 12.8°/mm with a constant bandpass filtering response of 29.5% 3-dB fractional bandwidth (FBW).

In this letter, a novel packaged linear displacement sensor integrated with inherent bandpass filter (BPF) is presented. The proposed filtering sensor is composed of a multimode resonator (MMR) and a pair of transmission line. Based on the insertion phase shifts, a displacement sensing function can be obtained along with a wideband bandpass filtering response. For verification, a prototype is simulated and measured. The measured results of the proposed sensors are in good agreement with the simulated ones, exhibiting an average phase sensitivity about 14°/mm with a wideband Chebyshev bandpass filtering response centered at 3.2 GHz of 56.7% 3-dB fractional bandwidth (FBW).

This article presents the reconfigurable matching of 11 kV medium voltage (MV) cross-linked polyethylene (XLPE) underground cable with cable joint using a novel parallel coupled line (PCL) impedance transformer. For S-parameters characterization operated at TV white space (TVWS)-based power line communication (PLC) spectrum ranged from 470 to 790 MHz, the proposed reconfigurable PCL impedance transformer with loaded and coupled lumped capacitors (LC2), namely PCL with LC2 (PCL-LC2) is designed for the highest frequency impedance matching in TVWS. Integrating four capacitors gives the coupled line different coupling coefficients and achieves wide frequency tunability. From the experimental results of the 700-mm long cable section sample, reconfigurable modeling for 770 MHz with the 14-dB return loss of cable without a joint and the 15-dB return loss of cable with a joint is realized.

Paper-based artifacts, such as ink and wash paintings, paper cuts, etc., when exposed in environment for a long time, are prone to embrittling, yellowing and ageing because of ultraviolet light and weather elements. In a museum, special measurements are adopted to avoid these damages, but for common households, a functional coating is a good solution. However, this is not an easy task as the coating must be removable and cannot damage the articles. Graphene oxide (GO) has the potential as ultraviolet shielding material for the protection of paper-based artifacts, but the application of monolithic GO coatings on paper-based artifacts is difficult. In this work, feasible GO/polyacrylonitrile composite films were prepared and their protection properties for rice paper were explored experimentally. When GO loading reached 2 %, the UV-A and UV-B blocking percentages of the film were 57.47 % and 70.86 %, respectively, with a visible light transmittance of 77.09 %. These films also performed good moisture resistance. With a good flexibility, they could be easily transferred onto and peeled off the rice paper surface without damaging the paper texture and patterns on it. These films basically meet the demand of paper-based artifacts protection.

Spotted fever group rickettsiae, mainly maintained and transmitted by ticks, are important etiological agents of (re)emerging zoonotic diseases worldwide. It is of great significance to investigate spotted fever group rickettsiae in ticks in different areas for the prevention and control of rickettsioses. In this study, a total of 305 ticks were collected from wild and domestic animals in Chongqing, Guizhou, Yunnan, and Guangxi provinces of southwestern China during 2017–2019 and examined for the presence of spotted fever group rickettsiae by PCR with primers targeting the partial gltA, ompA, rrs, and htrAgenes. Results showed that two spotted fever group rickettsiae species, including the pathogenic CandidatusRickettsia jingxinensis (Rickettsiales: Rickettsiaceae) and a potential novel species Rickettsiasp. sw (Rickettsiales: Rickettsiaceae), were identified. The Ca.R. jingxinensis sequences were recovered from Rhipicephalus microplus(Ixodida: Ixodidae) and Haemaphysalis longicornis(Ixodida: Ixodidae) ticks and phylogenetically clustered with previous Ca.R. jingxinensis, Ca.R. longicornii (Rickettsiales: Rickettsiaceae), and Rickettsiasp. XY118 (Rickettsiales: Rickettsiaceae) strains. Rickettsiasp. sw was detected in Amblyomma geoemydae(Ixodida: Ixodidae) and Rh. microplus. Interestingly, as far as we know, this was the first report of Rickettsia(Rickettsiales: Rickettsiaceae) in A. geoemydae. Phylogenetic analyses indicated that this potential novel species was closely related to R. aeschlimannii(Rickettsiales: Rickettsiaceae) with gltAand ompAgenes and grouped in a cluster composed of R. montanensis(Rickettsiales: Rickettsiaceae), R. raoultii(Rickettsiales: Rickettsiaceae), R. aeschlimannii, R. massiliae(Rickettsiales: Rickettsiaceae), and R. rhipicephali(Rickettsiales: Rickettsiaceae) with htrA, while formed a separate clade with rrs. The pathogenicity of Rickettsiasp. sw should be further confirmed. These results expand the knowledge of the geographical distribution and vector distribution of spotted fever group rickettsiae in China and are useful for assessing the potential public health risk.

We screened 104 snakes with respiratory disease, collected from 52 snake farms in Guangxi Province, China, for pathogens. Ferlaviruses were detected in 70 of 104 lung samples by reverse-transcription PCR; 34 of 52 of the snake farms were positive for ferlaviruses. No reovirus, adenovirus, sunshine virus, or nidovirus was detected in any of the snakes. We obtained 96 bacterial isolates from snake organs, of which the most commonly isolated species were Salmonella(18) and Proteus(16). Sequence analysis, based on 27 partial RNA-dependent RNA polymerase gene (L) sequences, revealed that ferlaviruses from Guangxi and the known GenBank strains clustered together and formed 3 genogroups. The nucleotide and deduced amino acid homologies of ferlaviruses were 84.3–100% and 95.0–100% within groups, respectively, and 77.0–81.6% and 90.4–95.2% between groups, respectively. Ferlaviruses from Guangxi had close genetic relationships with the known GenBank strains. Our results indicate that ferlaviruses are common in snakes with respiratory disease on the farms of Guangxi that we sampled, and that ferlavirus molecular epidemiology is both diverse and complex.

To investigate the fatigue property of A356 cast aluminum alloy, the pore size distribution in two kinds of A356 alloy were statistically tested, and the S-N curves were plotted by conducting four-point bend fatigue test, then the fractography of the fatigue specimens were examined under scan electron microscope (SEM). It was indicated that the fatigue strength of the A356.2 alloy contenting more large pores and rougher crystalline grain was lower than that of A356.1 alloy, though the yield strength of A356.2 alloy was higher. Most of the fatigue cracks initiated from the pores that located on or close to the surface of the specimens, and the fracture of the specimens were induced from the growth of multi-sites initiated fatigue crack.

A beamspace-time (BT) RAKE receiver is proposed for multiple accessinterference (MAI) suppression and multipath diversity reception insectored wireless CDMA communications. The scheme involves three stages.First, a set of adaptive beamformers encompassing a prescribed angular sectoris constructed on an antenna array, each providing effective suppression ofout-of-sector MAI and reception of in-sector signal. Second, a set of adaptivecorrelators is attached to each beam to combat in-sector MAI. Finally, thebeamspace correlator output data are combined to capture the signal multipathscoherently.The above three-stage operation is performed in a blind mode inthat no training signal is needed. The only information required is the signature,timing and a rough estimate of the angle of arrival (AOA) of the desired signal.

Osteoarthritis (OA) is an age-related degenerative disease. Oxidative stress (OS) modulates OA pathogenesis by enhancing chondrocyte apoptosis and extracellular matrix (ECM) degeneration via activation of the endoplasmic reticulum (ER) stress. Prior studies revealed that safranal plays a critical role in multiple diseases treatments, but there are no reports on its effect on OA. Therefore, investigating the effect of safranal on OA is needed. As a compound that can lead excessive reactive oxygen species (ROS) accumulation, tert-butyl hydroperoxide (TBHP) was used to induce OS and OS-mediated endoplasmic reticulum (ER) stress for imitating OA in vitro. Besides, the bilateral medial meniscus was removed to induce joint instability and excessive friction of the joint surface to establish destabilization of medial meniscus for imitating the initiation and progression of OA in vivo. We, next, conducted Western blot and RT-PCR analyses to identify biomarkers of the underlying signaling pathway. Our results demonstrated that 30 μM safranal strongly upregulated Sirt1 expression, suppressed TBHP-mediated ER stress, and, in turn, prevented chondrocyte apoptosis and ECM degeneration. Furthermore, compared with the other two classic signaling pathways of ER stress, safranal can inhibit the PERK-eIF2α-CHOP axis at the lower concentration (5 and 15 μM). In vivo, using Safranin O staining, X-ray, immunofluorescence (IF), and immunohistochemical (IHC) staining, we demonstrated that OA progression can be postponed with intraperitoneal injection of 90 and 180 mg/kg safranal in an OA mouse model. Taken together, our analyses revealed that safranal can potentially prevent OA development.

Cam and follower surfaces in line contact are considered. The general equations of curvature analysis for a 3-link cam-follower mechanism are based on the layout of the general coordinate systems, the matrix method, the basic kinematic relationship of contact surfaces, and the definitions of limit functions. For the given input–output relation and generating surface, the principal curvatures of the generated surface, the relative normal curvatures, and the undercut are expressed in concise form and can be applied to all planar and spatial cam-follower mechanisms. Three applied examples are given.

Ticks and tick-borne rickettsial diseases have been gaining greater attention in China over the past decade. However, most published studies to date have occurred in Northern China, with limited investigations occurring in China’s southern provinces. As part of larger surveillance efforts, a cross-sectional survey was conducted in six sites at Guangdong, Guangxi and Yunnan investigating rickettsial infection in ticks. A total of 581 ticks were collected from hosts and screened via PCR, targeting rrs, gltA, ompB, sca4,and ompAgene fragments. Two of 12 Haemaphysalis formosensisticks were infected with novel Rickettsiastrain GD01, which was closest phylogenetically (97.3–98.9 % identity) to Rickettsia tamuraestrain AT-1, but not within the same clade. Another detected strain (GD02) shared similar identity, 99–100 % across four gene targets, to recently detected CandidatusRickettsia longicornii isolate ROK-HL727, with an overall prevalence of 12.5 % (71/569). The presence of such pathogens calls for increased public health attention and active surveillance in patients reporting recent tick bites.